+++ /dev/null
-/*
-** Copyright (c) 1991, 1994, 1997, 1998 D. Richard Hipp
-**
-** This file contains all sources (including headers) to the LEMON
-** LALR(1) parser generator. The sources have been combined into a
-** single file to make it easy to include LEMON as part of another
-** program.
-**
-** This program is free software; you can redistribute it and/or
-** modify it under the terms of the GNU General Public
-** License as published by the Free Software Foundation; either
-** version 2 of the License, or (at your option) any later version.
-**
-** This program is distributed in the hope that it will be useful,
-** but WITHOUT ANY WARRANTY; without even the implied warranty of
-** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-** General Public License for more details.
-**
-** You should have received a copy of the GNU General Public
-** License along with this library; if not, write to the
-** Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-** Boston, MA 02111-1307, USA.
-**
-** Author contact information:
-** drh@acm.org
-** http://www.hwaci.com/drh/
-**
-** $IdPath$
-** $Id: lemon.c,v 1.6 2002/04/07 21:57:43 peter Exp $
-*/
-#include <stdio.h>
-#include <stdarg.h>
-#include <stdlib.h>
-#include <string.h>
-#include <ctype.h>
-
-/*
- * Wrapper around "isupper()", "islower()", etc. to cast the argument to
- * "unsigned char", so that they at least handle non-ASCII 8-bit characters
- * (and don't provoke a pile of warnings from GCC).
- */
-#define safe_isupper(c) isupper((unsigned char)(c))
-#define safe_islower(c) islower((unsigned char)(c))
-#define safe_isalpha(c) isalpha((unsigned char)(c))
-#define safe_isalnum(c) isalnum((unsigned char)(c))
-#define safe_isspace(c) isspace((unsigned char)(c))
-
-extern int access(const char *, int);
-
-#ifndef __WIN32__
-# if defined(_WIN32) || defined(WIN32)
-# define __WIN32__
-# endif
-#endif
-
-/* #define PRIVATE static */
-#define PRIVATE
-
-#ifdef TEST
-#define MAXRHS 5 /* Set low to exercise exception code */
-#else
-#define MAXRHS 1000
-#endif
-
-/********** From the file "struct.h" *************************************/
-/*
-** Principal data structures for the LEMON parser generator.
-*/
-
-typedef enum {BOOL_FALSE=0, BOOL_TRUE} Boolean;
-
-/* Symbols (terminals and nonterminals) of the grammar are stored
-** in the following: */
-struct symbol {
- char *name; /* Name of the symbol */
- int index; /* Index number for this symbol */
- enum {
- TERMINAL,
- NONTERMINAL
- } type; /* Symbols are all either TERMINALS or NTs */
- struct rule *rule; /* Linked list of rules of this (if an NT) */
- int prec; /* Precedence if defined (-1 otherwise) */
- enum e_assoc {
- LEFT,
- RIGHT,
- NONE,
- UNK
- } assoc; /* Associativity if predecence is defined */
- char *firstset; /* First-set for all rules of this symbol */
- Boolean lambda; /* True if NT and can generate an empty string */
- char *destructor; /* Code which executes whenever this symbol is
- ** popped from the stack during error processing */
- int destructorln; /* Line number of destructor code */
- char *datatype; /* The data type of information held by this
- ** object. Only used if type==NONTERMINAL */
- int dtnum; /* The data type number. In the parser, the value
- ** stack is a union. The .yy%d element of this
- ** union is the correct data type for this object */
-};
-
-/* Each production rule in the grammar is stored in the following
-** structure. */
-struct rule {
- struct symbol *lhs; /* Left-hand side of the rule */
- char *lhsalias; /* Alias for the LHS (NULL if none) */
- int ruleline; /* Line number for the rule */
- int nrhs; /* Number of RHS symbols */
- struct symbol **rhs; /* The RHS symbols */
- char **rhsalias; /* An alias for each RHS symbol (NULL if none) */
- int line; /* Line number at which code begins */
- char *code; /* The code executed when this rule is reduced */
- struct symbol *precsym; /* Precedence symbol for this rule */
- int index; /* An index number for this rule */
- Boolean canReduce; /* True if this rule is ever reduced */
- struct rule *nextlhs; /* Next rule with the same LHS */
- struct rule *next; /* Next rule in the global list */
-};
-
-/* A configuration is a production rule of the grammar together with
-** a mark (dot) showing how much of that rule has been processed so far.
-** Configurations also contain a follow-set which is a list of terminal
-** symbols which are allowed to immediately follow the end of the rule.
-** Every configuration is recorded as an instance of the following: */
-struct config {
- struct rule *rp; /* The rule upon which the configuration is based */
- int dot; /* The parse point */
- char *fws; /* Follow-set for this configuration only */
- struct plink *fplp; /* Follow-set forward propagation links */
- struct plink *bplp; /* Follow-set backwards propagation links */
- struct state *stp; /* Pointer to state which contains this */
- enum {
- COMPLETE, /* The status is used during followset and */
- INCOMPLETE /* shift computations */
- } status;
- struct config *next; /* Next configuration in the state */
- struct config *bp; /* The next basis configuration */
-};
-
-/* Every shift or reduce operation is stored as one of the following */
-struct action {
- struct symbol *sp; /* The look-ahead symbol */
- enum e_action {
- SHIFT,
- ACCEPT,
- REDUCE,
- ERROR,
- CONFLICT, /* Was a reduce, but part of a conflict */
- SH_RESOLVED, /* Was a shift. Precedence resolved conflict */
- RD_RESOLVED, /* Was reduce. Precedence resolved conflict */
- NOT_USED /* Deleted by compression */
- } type;
- union {
- struct state *stp; /* The new state, if a shift */
- struct rule *rp; /* The rule, if a reduce */
- } x;
- struct action *next; /* Next action for this state */
- struct action *collide; /* Next action with the same hash */
-};
-
-/* Each state of the generated parser's finite state machine
-** is encoded as an instance of the following structure. */
-struct state {
- struct config *bp; /* The basis configurations for this state */
- struct config *cfp; /* All configurations in this set */
- int index; /* Sequencial number for this state */
- struct action *ap; /* Array of actions for this state */
- unsigned int naction; /* Number of actions for this state */
- int tabstart; /* First index of the action table */
- int tabdfltact; /* Default action */
-};
-
-/* A followset propagation link indicates that the contents of one
-** configuration followset should be propagated to another whenever
-** the first changes. */
-struct plink {
- struct config *cfp; /* The configuration to which linked */
- struct plink *next; /* The next propagate link */
-};
-
-/* The state vector for the entire parser generator is recorded as
-** follows. (LEMON uses no global variables and makes little use of
-** static variables. Fields in the following structure can be thought
-** of as begin global variables in the program.) */
-struct lemon {
- struct state **sorted; /* Table of states sorted by state number */
- struct rule *rule; /* List of all rules */
- int nstate; /* Number of states */
- int nrule; /* Number of rules */
- int nsymbol; /* Number of terminal and nonterminal symbols */
- int nterminal; /* Number of terminal symbols */
- struct symbol **symbols; /* Sorted array of pointers to symbols */
- int errorcnt; /* Number of errors */
- struct symbol *errsym; /* The error symbol */
- char *name; /* Name of the generated parser */
- char *arg; /* Declaration of the 3th argument to parser */
- char *tokentype; /* Type of terminal symbols in the parser stack */
- char *start; /* Name of the start symbol for the grammar */
- char *stacksize; /* Size of the parser stack */
- char *include; /* Code to put at the start of the C file */
- int includeln; /* Line number for start of include code */
- char *error; /* Code to execute when an error is seen */
- int errorln; /* Line number for start of error code */
- char *overflow; /* Code to execute on a stack overflow */
- int overflowln; /* Line number for start of overflow code */
- char *failure; /* Code to execute on parser failure */
- int failureln; /* Line number for start of failure code */
- char *accept; /* Code to execute when the parser excepts */
- int acceptln; /* Line number for the start of accept code */
- char *extracode; /* Code appended to the generated file */
- int extracodeln; /* Line number for the start of the extra code */
- char *tokendest; /* Code to execute to destroy token data */
- int tokendestln; /* Line number for token destroyer code */
- char *filename; /* Name of the input file */
- char *outname; /* Name of the current output file */
- char *tokenprefix; /* A prefix added to token names in the .h file */
- int nconflict; /* Number of parsing conflicts */
- int tablesize; /* Size of the parse tables */
- int basisflag; /* Print only basis configurations */
- char *argv0; /* Name of the program */
-};
-
-#define MemoryCheck(X) if((X)==0){ \
- memory_error(); \
-}
-
-void memory_error(void);
-char *msort(char *, char **, int (*)(const void *, const void *));
-
-/******** From the file "action.h" *************************************/
-struct action *Action_new(void);
-struct action *Action_sort(struct action *);
-void Action_add(struct action **, enum e_action, struct symbol *, void *);
-
-/********* From the file "assert.h" ************************************/
-void myassert(const char *, int);
-#ifndef NDEBUG
-# define assert(X) if(!(X))myassert(__FILE__,__LINE__)
-#else
-# define assert(X)
-#endif
-
-/********** From the file "build.h" ************************************/
-void FindRulePrecedences(struct lemon *);
-void FindFirstSets(struct lemon *);
-void FindStates(struct lemon *);
-void FindLinks(struct lemon *);
-void FindFollowSets(struct lemon *);
-void FindActions(struct lemon *);
-
-/********* From the file "configlist.h" *********************************/
-void Configlist_init(void);
-struct config *Configlist_add(struct rule *, int);
-struct config *Configlist_addbasis(struct rule *, int);
-void Configlist_closure(struct lemon *);
-void Configlist_sort(void);
-void Configlist_sortbasis(void);
-struct config *Configlist_return(void);
-struct config *Configlist_basis(void);
-void Configlist_eat(struct config *);
-void Configlist_reset(void);
-
-/********* From the file "error.h" ***************************************/
-#if __GNUC__ >= 2
-void ErrorMsg( const char *, int, const char *, ... )
- __attribute__((format (printf, 3, 4)));
-#else
-void ErrorMsg( const char *, int, const char *, ... );
-#endif
-
-/****** From the file "option.h" ******************************************/
-struct s_options {
- enum { OPT_FLAG=1, OPT_INT, OPT_DBL, OPT_STR,
- OPT_FFLAG, OPT_FINT, OPT_FDBL, OPT_FSTR} type;
- const char *label;
- union {
- void *val;
- void (*fflag)(int);
- void (*fint)(int);
- void (*fdbl)(double);
- void (*fstr)(const char *);
- } arg;
- const char *message;
-};
-int OptInit(char**,struct s_options*,FILE*);
-int OptNArgs(void);
-char *OptArg(int);
-void OptErr(int);
-void OptPrint(void);
-
-/******** From the file "parse.h" *****************************************/
-void Parse(struct lemon *lemp);
-
-/********* From the file "plink.h" ***************************************/
-struct plink *Plink_new(void);
-void Plink_add(struct plink **, struct config *);
-void Plink_copy(struct plink **, struct plink *);
-void Plink_delete(struct plink *);
-
-/********** From the file "report.h" *************************************/
-void Reprint(struct lemon *);
-void ReportOutput(struct lemon *);
-void ReportTable(struct lemon *, int);
-void ReportHeader(struct lemon *);
-void CompressTables(struct lemon *);
-
-/********** From the file "set.h" ****************************************/
-void SetSize(int N); /* All sets will be of size N */
-char *SetNew(void); /* A new set for element 0..N */
-void SetFree(char*); /* Deallocate a set */
-int SetAdd(char*,int); /* Add element to a set */
-int SetUnion(char *A,char *B); /* A <- A U B, thru element N */
-
-#define SetFind(X,Y) (X[Y]) /* True if Y is in set X */
-
-/**************** From the file "table.h" *********************************/
-/*
-** All code in this file has been automatically generated
-** from a specification in the file
-** "table.q"
-** by the associative array code building program "aagen".
-** Do not edit this file! Instead, edit the specification
-** file, then rerun aagen.
-*/
-/*
-** Code for processing tables in the LEMON parser generator.
-*/
-
-/* Routines for handling a strings */
-
-char *Strsafe(const char *);
-
-void Strsafe_init(void);
-int Strsafe_insert(char *);
-char *Strsafe_find(const char *);
-
-/* Routines for handling symbols of the grammar */
-
-struct symbol *Symbol_new(const char *x);
-int Symbolcmpp(const void *, const void *);
-void Symbol_init(void);
-int Symbol_insert(struct symbol *, char *);
-struct symbol *Symbol_find(const char *);
-struct symbol *Symbol_Nth(int);
-int Symbol_count(void);
-struct symbol **Symbol_arrayof(void);
-
-/* Routines to manage the state table */
-
-int Configcmp(const void *, const void *);
-struct state *State_new(void);
-void State_init(void);
-int State_insert(struct state *, struct config *);
-struct state *State_find(struct config *);
-struct state **State_arrayof(void);
-
-/* Routines used for efficiency in Configlist_add */
-
-void Configtable_init(void);
-int Configtable_insert(struct config *);
-struct config *Configtable_find(struct config *);
-void Configtable_clear(int(*)(struct config *));
-/****************** From the file "action.c" *******************************/
-/*
-** Routines processing parser actions in the LEMON parser generator.
-*/
-
-/* Allocate a new parser action */
-struct action *Action_new(void){
- static struct action *freelist = 0;
- struct action *new;
-
- if( freelist==0 ){
- int i;
- int amt = 100;
- freelist = (struct action *)malloc( sizeof(struct action)*amt );
- if( freelist==0 ){
- fprintf(stderr,"Unable to allocate memory for a new parser action.");
- exit(1);
- }
- for(i=0; i<amt-1; i++) freelist[i].next = &freelist[i+1];
- freelist[amt-1].next = 0;
- }
- new = freelist;
- freelist = freelist->next;
- return new;
-}
-
-/* Compare two actions */
-static int actioncmp(const void *ap1_arg, const void *ap2_arg)
-{
- const struct action *ap1 = ap1_arg, *ap2 = ap2_arg;
- int rc;
- rc = ap1->sp->index - ap2->sp->index;
- if( rc==0 ) rc = (int)ap1->type - (int)ap2->type;
- if( rc==0 ){
- assert( ap1->type==REDUCE || ap1->type==RD_RESOLVED || ap1->type==CONFLICT);
- assert( ap2->type==REDUCE || ap2->type==RD_RESOLVED || ap2->type==CONFLICT);
- rc = ap1->x.rp->index - ap2->x.rp->index;
- }
- return rc;
-}
-
-/* Sort parser actions */
-struct action *Action_sort(struct action *ap)
-{
- ap = (struct action *)msort((char *)ap,(char **)&ap->next,actioncmp);
- return ap;
-}
-
-void Action_add(struct action **app, enum e_action type, struct symbol *sp,
- void *arg)
-{
- struct action *new;
- new = Action_new();
- new->next = *app;
- *app = new;
- new->type = type;
- new->sp = sp;
- if( type==SHIFT ){
- new->x.stp = (struct state *)arg;
- }else{
- new->x.rp = (struct rule *)arg;
- }
-}
-/********************** From the file "assert.c" ****************************/
-/*
-** A more efficient way of handling assertions.
-*/
-void myassert(const char *file, int line)
-{
- fprintf(stderr,"Assertion failed on line %d of file \"%s\"\n",line,file);
- exit(1);
-}
-/********************** From the file "build.c" *****************************/
-/*
-** Routines to construction the finite state machine for the LEMON
-** parser generator.
-*/
-
-/* Find a precedence symbol of every rule in the grammar.
-**
-** Those rules which have a precedence symbol coded in the input
-** grammar using the "[symbol]" construct will already have the
-** rp->precsym field filled. Other rules take as their precedence
-** symbol the first RHS symbol with a defined precedence. If there
-** are not RHS symbols with a defined precedence, the precedence
-** symbol field is left blank.
-*/
-void FindRulePrecedences(struct lemon *xp)
-{
- struct rule *rp;
- for(rp=xp->rule; rp; rp=rp->next){
- if( rp->precsym==0 ){
- int i;
- for(i=0; i<rp->nrhs; i++){
- if( rp->rhs[i]->prec>=0 ){
- rp->precsym = rp->rhs[i];
- break;
- }
- }
- }
- }
- return;
-}
-
-/* Find all nonterminals which will generate the empty string.
-** Then go back and compute the first sets of every nonterminal.
-** The first set is the set of all terminal symbols which can begin
-** a string generated by that nonterminal.
-*/
-void FindFirstSets(struct lemon *lemp)
-{
- int i;
- struct rule *rp;
- int progress;
-
- for(i=0; i<lemp->nsymbol; i++){
- lemp->symbols[i]->lambda = BOOL_FALSE;
- }
- for(i=lemp->nterminal; i<lemp->nsymbol; i++){
- lemp->symbols[i]->firstset = SetNew();
- }
-
- /* First compute all lambdas */
- do{
- progress = 0;
- for(rp=lemp->rule; rp; rp=rp->next){
- if( rp->lhs->lambda ) continue;
- for(i=0; i<rp->nrhs; i++){
- if( rp->rhs[i]->lambda==BOOL_FALSE ) break;
- }
- if( i==rp->nrhs ){
- rp->lhs->lambda = BOOL_TRUE;
- progress = 1;
- }
- }
- }while( progress );
-
- /* Now compute all first sets */
- do{
- struct symbol *s1, *s2;
- progress = 0;
- for(rp=lemp->rule; rp; rp=rp->next){
- s1 = rp->lhs;
- for(i=0; i<rp->nrhs; i++){
- s2 = rp->rhs[i];
- if( s2->type==TERMINAL ){
- progress += SetAdd(s1->firstset,s2->index);
- break;
- }else if( s1==s2 ){
- if( s1->lambda==BOOL_FALSE ) break;
- }else{
- progress += SetUnion(s1->firstset,s2->firstset);
- if( s2->lambda==BOOL_FALSE ) break;
- }
- }
- }
- }while( progress );
- return;
-}
-
-/* Compute all LR(0) states for the grammar. Links
-** are added to between some states so that the LR(1) follow sets
-** can be computed later.
-*/
-PRIVATE struct state *getstate(struct lemon *); /* forward reference */
-void FindStates(lemp)
-struct lemon *lemp;
-{
- struct symbol *sp;
- struct rule *rp;
-
- Configlist_init();
-
- /* Find the start symbol */
- if( lemp->start ){
- sp = Symbol_find(lemp->start);
- if( sp==0 ){
- ErrorMsg(lemp->filename,0,
-"The specified start symbol \"%s\" is not \
-in a nonterminal of the grammar. \"%s\" will be used as the start \
-symbol instead.",lemp->start,lemp->rule->lhs->name);
- lemp->errorcnt++;
- sp = lemp->rule->lhs;
- }
- }else{
- sp = lemp->rule->lhs;
- }
-
- /* Make sure the start symbol doesn't occur on the right-hand side of
- ** any rule. Report an error if it does. (YACC would generate a new
- ** start symbol in this case.) */
- for(rp=lemp->rule; rp; rp=rp->next){
- int i;
- for(i=0; i<rp->nrhs; i++){
- if( rp->rhs[i]==sp ){
- ErrorMsg(lemp->filename,0,
-"The start symbol \"%s\" occurs on the \
-right-hand side of a rule. This will result in a parser which \
-does not work properly.",sp->name);
- lemp->errorcnt++;
- }
- }
- }
-
- /* The basis configuration set for the first state
- ** is all rules which have the start symbol as their
- ** left-hand side */
- for(rp=sp->rule; rp; rp=rp->nextlhs){
- struct config *newcfp;
- newcfp = Configlist_addbasis(rp,0);
- SetAdd(newcfp->fws,0);
- }
-
- /* Compute the first state. All other states will be
- ** computed automatically during the computation of the first one.
- ** The returned pointer to the first state is not used. */
- (void)getstate(lemp);
- return;
-}
-
-/* Return a pointer to a state which is described by the configuration
-** list which has been built from calls to Configlist_add.
-*/
-PRIVATE void buildshifts(struct lemon *, struct state *); /* Forwd ref */
-PRIVATE struct state *getstate(struct lemon *lemp)
-{
- struct config *cfp, *bp;
- struct state *stp;
-
- /* Extract the sorted basis of the new state. The basis was constructed
- ** by prior calls to "Configlist_addbasis()". */
- Configlist_sortbasis();
- bp = Configlist_basis();
-
- /* Get a state with the same basis */
- stp = State_find(bp);
- if( stp ){
- /* A state with the same basis already exists! Copy all the follow-set
- ** propagation links from the state under construction into the
- ** preexisting state, then return a pointer to the preexisting state */
- struct config *x, *y;
- for(x=bp, y=stp->bp; x && y; x=x->bp, y=y->bp){
- Plink_copy(&y->bplp,x->bplp);
- Plink_delete(x->fplp);
- x->fplp = x->bplp = 0;
- }
- cfp = Configlist_return();
- Configlist_eat(cfp);
- }else{
- /* This really is a new state. Construct all the details */
- Configlist_closure(lemp); /* Compute the configuration closure */
- Configlist_sort(); /* Sort the configuration closure */
- cfp = Configlist_return(); /* Get a pointer to the config list */
- stp = State_new(); /* A new state structure */
- MemoryCheck(stp);
- stp->bp = bp; /* Remember the configuration basis */
- stp->cfp = cfp; /* Remember the configuration closure */
- stp->index = lemp->nstate++; /* Every state gets a sequence number */
- stp->ap = 0; /* No actions, yet. */
- State_insert(stp,stp->bp); /* Add to the state table */
- buildshifts(lemp,stp); /* Recursively compute successor states */
- }
- return stp;
-}
-
-/* Construct all successor states to the given state. A "successor"
-** state is any state which can be reached by a shift action.
-*/
-PRIVATE void buildshifts(
- struct lemon *lemp,
- struct state *stp) /* The state from which successors are computed */
-{
- struct config *cfp; /* For looping thru the config closure of "stp" */
- struct config *bcfp; /* For the inner loop on config closure of "stp" */
- struct config *new; /* */
- struct symbol *sp; /* Symbol following the dot in configuration "cfp" */
- struct symbol *bsp; /* Symbol following the dot in configuration "bcfp" */
- struct state *newstp; /* A pointer to a successor state */
-
- /* Each configuration becomes complete after it contibutes to a successor
- ** state. Initially, all configurations are incomplete */
- for(cfp=stp->cfp; cfp; cfp=cfp->next) cfp->status = INCOMPLETE;
-
- /* Loop through all configurations of the state "stp" */
- for(cfp=stp->cfp; cfp; cfp=cfp->next){
- if( cfp->status==COMPLETE ) continue; /* Already used by inner loop */
- if( cfp->dot>=cfp->rp->nrhs ) continue; /* Can't shift this config */
- Configlist_reset(); /* Reset the new config set */
- sp = cfp->rp->rhs[cfp->dot]; /* Symbol after the dot */
-
- /* For every configuration in the state "stp" which has the symbol "sp"
- ** following its dot, add the same configuration to the basis set under
- ** construction but with the dot shifted one symbol to the right. */
- for(bcfp=cfp; bcfp; bcfp=bcfp->next){
- if( bcfp->status==COMPLETE ) continue; /* Already used */
- if( bcfp->dot>=bcfp->rp->nrhs ) continue; /* Can't shift this one */
- bsp = bcfp->rp->rhs[bcfp->dot]; /* Get symbol after dot */
- if( bsp!=sp ) continue; /* Must be same as for "cfp" */
- bcfp->status = COMPLETE; /* Mark this config as used */
- new = Configlist_addbasis(bcfp->rp,bcfp->dot+1);
- Plink_add(&new->bplp,bcfp);
- }
-
- /* Get a pointer to the state described by the basis configuration set
- ** constructed in the preceding loop */
- newstp = getstate(lemp);
-
- /* The state "newstp" is reached from the state "stp" by a shift action
- ** on the symbol "sp" */
- Action_add(&stp->ap,SHIFT,sp,newstp);
- }
-}
-
-/*
-** Construct the propagation links
-*/
-void FindLinks(struct lemon *lemp)
-{
- int i;
- struct config *cfp, *other;
- struct state *stp;
- struct plink *plp;
-
- /* Housekeeping detail:
- ** Add to every propagate link a pointer back to the state to
- ** which the link is attached. */
- for(i=0; i<lemp->nstate; i++){
- stp = lemp->sorted[i];
- for(cfp=stp->cfp; cfp; cfp=cfp->next){
- cfp->stp = stp;
- }
- }
-
- /* Convert all backlinks into forward links. Only the forward
- ** links are used in the follow-set computation. */
- for(i=0; i<lemp->nstate; i++){
- stp = lemp->sorted[i];
- for(cfp=stp->cfp; cfp; cfp=cfp->next){
- for(plp=cfp->bplp; plp; plp=plp->next){
- other = plp->cfp;
- Plink_add(&other->fplp,cfp);
- }
- }
- }
-}
-
-/* Compute all followsets.
-**
-** A followset is the set of all symbols which can come immediately
-** after a configuration.
-*/
-void FindFollowSets(struct lemon *lemp)
-{
- int i;
- struct config *cfp;
- struct plink *plp;
- int progress;
- int change;
-
- for(i=0; i<lemp->nstate; i++){
- for(cfp=lemp->sorted[i]->cfp; cfp; cfp=cfp->next){
- cfp->status = INCOMPLETE;
- }
- }
-
- do{
- progress = 0;
- for(i=0; i<lemp->nstate; i++){
- for(cfp=lemp->sorted[i]->cfp; cfp; cfp=cfp->next){
- if( cfp->status==COMPLETE ) continue;
- for(plp=cfp->fplp; plp; plp=plp->next){
- change = SetUnion(plp->cfp->fws,cfp->fws);
- if( change ){
- plp->cfp->status = INCOMPLETE;
- progress = 1;
- }
- }
- cfp->status = COMPLETE;
- }
- }
- }while( progress );
-}
-
-static int resolve_conflict(struct action *, struct action *, struct symbol *);
-
-/* Compute the reduce actions, and resolve conflicts.
-*/
-void FindActions(struct lemon *lemp)
-{
- int i,j;
- struct config *cfp;
- struct state *stp;
- struct symbol *sp;
- struct rule *rp;
-
- /* Add all of the reduce actions
- ** A reduce action is added for each element of the followset of
- ** a configuration which has its dot at the extreme right.
- */
- for(i=0; i<lemp->nstate; i++){ /* Loop over all states */
- stp = lemp->sorted[i];
- for(cfp=stp->cfp; cfp; cfp=cfp->next){ /* Loop over all configurations */
- if( cfp->rp->nrhs==cfp->dot ){ /* Is dot at extreme right? */
- for(j=0; j<lemp->nterminal; j++){
- if( SetFind(cfp->fws,j) ){
- /* Add a reduce action to the state "stp" which will reduce by the
- ** rule "cfp->rp" if the lookahead symbol is "lemp->symbols[j]" */
- Action_add(&stp->ap,REDUCE,lemp->symbols[j],cfp->rp);
- }
- }
- }
- }
- }
-
- /* Add the accepting token */
- if( lemp->start ){
- sp = Symbol_find(lemp->start);
- if( sp==0 ) sp = lemp->rule->lhs;
- }else{
- sp = lemp->rule->lhs;
- }
- /* Add to the first state (which is always the starting state of the
- ** finite state machine) an action to ACCEPT if the lookahead is the
- ** start nonterminal. */
- Action_add(&lemp->sorted[0]->ap,ACCEPT,sp,0);
-
- /* Resolve conflicts */
- for(i=0; i<lemp->nstate; i++){
- struct action *ap, *nap;
- struct state *stp2;
- stp2 = lemp->sorted[i];
- assert( stp2->ap );
- stp2->ap = Action_sort(stp2->ap);
- for(ap=stp2->ap; ap && ap->next; ap=nap){
- for(nap=ap->next; nap && nap->sp==ap->sp; nap=nap->next){
- /* The two actions "ap" and "nap" have the same lookahead.
- ** Figure out which one should be used */
- lemp->nconflict += resolve_conflict(ap,nap,lemp->errsym);
- }
- }
- }
-
- /* Report an error for each rule that can never be reduced. */
- for(rp=lemp->rule; rp; rp=rp->next) rp->canReduce = BOOL_FALSE;
- for(i=0; i<lemp->nstate; i++){
- struct action *ap;
- for(ap=lemp->sorted[i]->ap; ap; ap=ap->next){
- if( ap->type==REDUCE ) ap->x.rp->canReduce = BOOL_TRUE;
- }
- }
- for(rp=lemp->rule; rp; rp=rp->next){
- if( rp->canReduce ) continue;
- ErrorMsg(lemp->filename,rp->ruleline,"This rule can not be reduced.\n");
- lemp->errorcnt++;
- }
-}
-
-/* Resolve a conflict between the two given actions. If the
-** conflict can't be resolve, return non-zero.
-**
-** NO LONGER TRUE:
-** To resolve a conflict, first look to see if either action
-** is on an error rule. In that case, take the action which
-** is not associated with the error rule. If neither or both
-** actions are associated with an error rule, then try to
-** use precedence to resolve the conflict.
-**
-** If either action is a SHIFT, then it must be apx. This
-** function won't work if apx->type==REDUCE and apy->type==SHIFT.
-*/
-static int resolve_conflict(
- struct action *apx,
- struct action *apy,
- struct symbol *errsym) /* The error symbol (if defined. NULL otherwise) */
-{
- struct symbol *spx, *spy;
- int errcnt = 0;
- assert( apx->sp==apy->sp ); /* Otherwise there would be no conflict */
- if( apx->type==SHIFT && apy->type==REDUCE ){
- spx = apx->sp;
- spy = apy->x.rp->precsym;
- if( spy==0 || spx->prec<0 || spy->prec<0 ){
- /* Not enough precedence information. */
- apy->type = CONFLICT;
- errcnt++;
- }else if( spx->prec>spy->prec ){ /* Lower precedence wins */
- apy->type = RD_RESOLVED;
- }else if( spx->prec<spy->prec ){
- apx->type = SH_RESOLVED;
- }else if( spx->prec==spy->prec && spx->assoc==RIGHT ){ /* Use operator */
- apy->type = RD_RESOLVED; /* associativity */
- }else if( spx->prec==spy->prec && spx->assoc==LEFT ){ /* to break tie */
- apx->type = SH_RESOLVED;
- }else{
- assert( spx->prec==spy->prec && spx->assoc==NONE );
- apy->type = CONFLICT;
- errcnt++;
- }
- }else if( apx->type==REDUCE && apy->type==REDUCE ){
- spx = apx->x.rp->precsym;
- spy = apy->x.rp->precsym;
- if( spx==0 || spy==0 || spx->prec<0 ||
- spy->prec<0 || spx->prec==spy->prec ){
- apy->type = CONFLICT;
- errcnt++;
- }else if( spx->prec>spy->prec ){
- apy->type = RD_RESOLVED;
- }else if( spx->prec<spy->prec ){
- apx->type = RD_RESOLVED;
- }
- }else{
- /* Can't happen. Shifts have to come before Reduces on the
- ** list because the reduces were added last. Hence, if apx->type==REDUCE
- ** then it is impossible for apy->type==SHIFT */
- }
- return errcnt;
-}
-/********************* From the file "configlist.c" *************************/
-/*
-** Routines to processing a configuration list and building a state
-** in the LEMON parser generator.
-*/
-
-static struct config *freelist = 0; /* List of free configurations */
-static struct config *current = 0; /* Top of list of configurations */
-static struct config **currentend = 0; /* Last on list of configs */
-static struct config *basis = 0; /* Top of list of basis configs */
-static struct config **basisend = 0; /* End of list of basis configs */
-
-struct config *newconfig(void);
-void deleteconfig(struct config *);
-
-/* Return a pointer to a new configuration */
-PRIVATE struct config *newconfig(void){
- struct config *new;
- if( freelist==0 ){
- int i;
- int amt = 3;
- freelist = (struct config *)malloc( sizeof(struct config)*amt );
- if( freelist==0 ){
- fprintf(stderr,"Unable to allocate memory for a new configuration.");
- exit(1);
- }
- for(i=0; i<amt-1; i++) freelist[i].next = &freelist[i+1];
- freelist[amt-1].next = 0;
- }
- new = freelist;
- freelist = freelist->next;
- return new;
-}
-
-/* The configuration "old" is no longer used */
-PRIVATE void deleteconfig(struct config *old)
-{
- old->next = freelist;
- freelist = old;
-}
-
-/* Initialized the configuration list builder */
-void Configlist_init(void){
- current = 0;
- currentend = ¤t;
- basis = 0;
- basisend = &basis;
- Configtable_init();
- return;
-}
-
-/* Initialized the configuration list builder */
-void Configlist_reset(void){
- current = 0;
- currentend = ¤t;
- basis = 0;
- basisend = &basis;
- Configtable_clear(0);
- return;
-}
-
-/* Add another configuration to the configuration list */
-struct config *Configlist_add(
- struct rule *rp, /* The rule */
- int dot) /* Index into the RHS of the rule where the dot goes */
-{
- struct config *cfp, model;
-
- assert( currentend!=0 );
- model.rp = rp;
- model.dot = dot;
- cfp = Configtable_find(&model);
- if( cfp==0 ){
- cfp = newconfig();
- cfp->rp = rp;
- cfp->dot = dot;
- cfp->fws = SetNew();
- cfp->stp = 0;
- cfp->fplp = cfp->bplp = 0;
- cfp->next = 0;
- cfp->bp = 0;
- *currentend = cfp;
- currentend = &cfp->next;
- Configtable_insert(cfp);
- }
- return cfp;
-}
-
-/* Add a basis configuration to the configuration list */
-struct config *Configlist_addbasis(struct rule *rp, int dot)
-{
- struct config *cfp, model;
-
- assert( basisend!=0 );
- assert( currentend!=0 );
- model.rp = rp;
- model.dot = dot;
- cfp = Configtable_find(&model);
- if( cfp==0 ){
- cfp = newconfig();
- cfp->rp = rp;
- cfp->dot = dot;
- cfp->fws = SetNew();
- cfp->stp = 0;
- cfp->fplp = cfp->bplp = 0;
- cfp->next = 0;
- cfp->bp = 0;
- *currentend = cfp;
- currentend = &cfp->next;
- *basisend = cfp;
- basisend = &cfp->bp;
- Configtable_insert(cfp);
- }
- return cfp;
-}
-
-/* Compute the closure of the configuration list */
-void Configlist_closure(struct lemon *lemp)
-{
- struct config *cfp, *newcfp;
- struct rule *rp, *newrp;
- struct symbol *sp, *xsp;
- int i, dot;
-
- assert( currentend!=0 );
- for(cfp=current; cfp; cfp=cfp->next){
- rp = cfp->rp;
- dot = cfp->dot;
- if( dot>=rp->nrhs ) continue;
- sp = rp->rhs[dot];
- if( sp->type==NONTERMINAL ){
- if( sp->rule==0 && sp!=lemp->errsym ){
- ErrorMsg(lemp->filename,rp->line,"Nonterminal \"%s\" has no rules.",
- sp->name);
- lemp->errorcnt++;
- }
- for(newrp=sp->rule; newrp; newrp=newrp->nextlhs){
- newcfp = Configlist_add(newrp,0);
- for(i=dot+1; i<rp->nrhs; i++){
- xsp = rp->rhs[i];
- if( xsp->type==TERMINAL ){
- SetAdd(newcfp->fws,xsp->index);
- break;
- }else{
- SetUnion(newcfp->fws,xsp->firstset);
- if( xsp->lambda==BOOL_FALSE ) break;
- }
- }
- if( i==rp->nrhs ) Plink_add(&cfp->fplp,newcfp);
- }
- }
- }
- return;
-}
-
-/* Sort the configuration list */
-void Configlist_sort(void){
- current = (struct config *)msort((char *)current,(char **)&(current->next),Configcmp);
- currentend = 0;
- return;
-}
-
-/* Sort the basis configuration list */
-void Configlist_sortbasis(void){
- basis = (struct config *)msort((char *)current,(char **)&(current->bp),Configcmp);
- basisend = 0;
- return;
-}
-
-/* Return a pointer to the head of the configuration list and
-** reset the list */
-struct config *Configlist_return(void){
- struct config *old;
- old = current;
- current = 0;
- currentend = 0;
- return old;
-}
-
-/* Return a pointer to the head of the configuration list and
-** reset the list */
-struct config *Configlist_basis(void){
- struct config *old;
- old = basis;
- basis = 0;
- basisend = 0;
- return old;
-}
-
-/* Free all elements of the given configuration list */
-void Configlist_eat(struct config *cfp)
-{
- struct config *nextcfp;
- for(; cfp; cfp=nextcfp){
- nextcfp = cfp->next;
- assert( cfp->fplp==0 );
- assert( cfp->bplp==0 );
- if( cfp->fws ) SetFree(cfp->fws);
- deleteconfig(cfp);
- }
- return;
-}
-/***************** From the file "error.c" *********************************/
-/*
-** Code for printing error message.
-*/
-
-/* Find a good place to break "msg" so that its length is at least "min"
-** but no more than "max". Make the point as close to max as possible.
-*/
-static int findbreak(char *msg, int min, int max)
-{
- int i,spot;
- char c;
- for(i=spot=min; i<=max; i++){
- c = msg[i];
- if( c=='\t' ) msg[i] = ' ';
- if( c=='\n' ){ msg[i] = ' '; spot = i; break; }
- if( c==0 ){ spot = i; break; }
- if( c=='-' && i<max-1 ) spot = i+1;
- if( c==' ' ) spot = i;
- }
- return spot;
-}
-
-/*
-** The error message is split across multiple lines if necessary. The
-** splits occur at a space, if there is a space available near the end
-** of the line.
-*/
-#define ERRMSGSIZE 10000 /* Hope this is big enough. No way to error check */
-#define LINEWIDTH 79 /* Max width of any output line */
-#define PREFIXLIMIT 30 /* Max width of the prefix on each line */
-void ErrorMsg(const char *filename, int lineno, const char *format, ...)
-{
- char errmsg[ERRMSGSIZE];
- char prefix[PREFIXLIMIT+10];
- int errmsgsize;
- int prefixsize;
- int availablewidth;
- va_list ap;
- int end, restart, base;
-
- va_start(ap, format);
- /* Prepare a prefix to be prepended to every output line */
- if( lineno>0 ){
- sprintf(prefix,"%.*s:%d: ",PREFIXLIMIT-10,filename,lineno);
- }else{
- sprintf(prefix,"%.*s: ",PREFIXLIMIT-10,filename);
- }
- prefixsize = strlen(prefix);
- availablewidth = LINEWIDTH - prefixsize;
-
- /* Generate the error message */
- vsprintf(errmsg,format,ap);
- va_end(ap);
- errmsgsize = strlen(errmsg);
- /* Remove trailing '\n's from the error message. */
- while( errmsgsize>0 && errmsg[errmsgsize-1]=='\n' ){
- errmsg[--errmsgsize] = 0;
- }
-
- /* Print the error message */
- base = 0;
- while( errmsg[base]!=0 ){
- end = restart = findbreak(&errmsg[base],0,availablewidth);
- restart += base;
- while( errmsg[restart]==' ' ) restart++;
- fprintf(stdout,"%s%.*s\n",prefix,end,&errmsg[base]);
- base = restart;
- }
-}
-/**************** From the file "main.c" ************************************/
-/*
-** Main program file for the LEMON parser generator.
-*/
-
-void setlempar(const char *);
-void setoutput(const char *);
-
-/* Report an out-of-memory condition and abort. This function
-** is used mostly by the "MemoryCheck" macro in struct.h
-*/
-void memory_error(void){
- fprintf(stderr,"Out of memory. Aborting...\n");
- exit(1);
-}
-
-static const char *lempar_locations[] = {
- NULL, "lempar.c"
-};
-
-void setlempar(const char *lempar)
-{
- if (access(lempar, 004)) {
- perror(lempar);
- exit(1);
- }
- lempar_locations[0] = lempar;
-}
-
-static char *output_file = NULL;
-
-void setoutput(const char *base)
-{
- if ((output_file = malloc(strlen(base) + 1)))
- sprintf(output_file, "%s.", base);
-}
-
-/* The main program. Parse the command line and do it... */
-int main(int argc, char **argv)
-{
- static int version = 0;
- static int rpflag = 0;
- static int basisflag = 0;
- static int compress = 0;
- static int quiet = 0;
- static int statistics = 0;
- static int mhflag = 0;
- static struct s_options options[] = {
- {OPT_FLAG, "b", {&basisflag}, "Print only the basis in report."},
- {OPT_FLAG, "c", {&compress}, "Don't compress the action table."},
- {OPT_FLAG, "g", {&rpflag}, "Print grammar without actions."},
- {OPT_FLAG, "m", {&mhflag}, "Output a makeheaders compatible file."},
- {OPT_FSTR, "o", {0}, "Set the dirname/basename for the output file(s)."},
- {OPT_FLAG, "q", {&quiet}, "(Quiet) Don't print the report file."},
- {OPT_FLAG, "s", {&statistics}, "Print parser stats to standard output."},
- {OPT_FSTR, "t", {0}, "An alternative template -- instead of "
- "\"./lempar.c\"."},
- {OPT_FLAG, "x", {&version}, "Print the version number."},
- {OPT_FLAG,0,{0},0}
- };
- int i;
- struct lemon lem;
-
- /* Initialize function union members of options array */
- options[4].arg.fstr = setoutput;
- options[7].arg.fstr = setlempar;
-
- OptInit(argv,options,stderr);
- if( version ){
- printf("Lemon version 1.0\n"
- "Copyright 1991-1997 by D. Richard Hipp\n"
- "Freely distributable under the GNU Public License.\n"
- );
- exit(0);
- }
- if( OptNArgs()!=1 ){
- fprintf(stderr,"Exactly one filename argument is required.\n");
- exit(1);
- }
- lem.errorcnt = 0;
-
- /* Initialize the machine */
- Strsafe_init();
- Symbol_init();
- State_init();
- lem.argv0 = argv[0];
- lem.filename = OptArg(0);
- lem.basisflag = basisflag;
- lem.nconflict = 0;
- lem.name = lem.include = lem.arg = lem.tokentype = lem.start = 0;
- lem.stacksize = 0;
- lem.error = lem.overflow = lem.failure = lem.accept = lem.tokendest =
- lem.tokenprefix = lem.outname = lem.extracode = 0;
- lem.tablesize = 0;
- Symbol_new("$");
- lem.errsym = Symbol_new("error");
-
- /* Parse the input file */
- Parse(&lem);
- if( lem.errorcnt ) exit(lem.errorcnt);
- if( lem.rule==0 ){
- fprintf(stderr,"Empty grammar.\n");
- exit(1);
- }
-
- /* Count and index the symbols of the grammar */
- lem.nsymbol = Symbol_count();
- Symbol_new("{default}");
- lem.symbols = Symbol_arrayof();
- qsort(lem.symbols,lem.nsymbol+1,sizeof(struct symbol*),Symbolcmpp);
- for(i=0; i<=lem.nsymbol; i++) lem.symbols[i]->index = i;
- for(i=1; safe_isupper(lem.symbols[i]->name[0]); i++);
- lem.nterminal = i;
-
- /* Generate a reprint of the grammar, if requested on the command line */
- if( rpflag ){
- Reprint(&lem);
- }else{
- /* Initialize the size for all follow and first sets */
- SetSize(lem.nterminal);
-
- /* Find the precedence for every production rule (that has one) */
- FindRulePrecedences(&lem);
-
- /* Compute the lambda-nonterminals and the first-sets for every
- ** nonterminal */
- FindFirstSets(&lem);
-
- /* Compute all LR(0) states. Also record follow-set propagation
- ** links so that the follow-set can be computed later */
- lem.nstate = 0;
- FindStates(&lem);
- lem.sorted = State_arrayof();
-
- /* Tie up loose ends on the propagation links */
- FindLinks(&lem);
-
- /* Compute the follow set of every reducible configuration */
- FindFollowSets(&lem);
-
- /* Compute the action tables */
- FindActions(&lem);
-
- /* Compress the action tables */
- if( compress==0 ) CompressTables(&lem);
-
- /* Generate a report of the parser generated. (the "y.output" file) */
- if( !quiet ) ReportOutput(&lem);
-
- /* Generate the source code for the parser */
- ReportTable(&lem, mhflag);
-
- /* Produce a header file for use by the scanner. (This step is
- ** omitted if the "-m" option is used because makeheaders will
- ** generate the file for us.) */
- if( !mhflag ) ReportHeader(&lem);
- }
- if( statistics ){
- printf("Parser statistics: %d terminals, %d nonterminals, %d rules\n",
- lem.nterminal, lem.nsymbol - lem.nterminal, lem.nrule);
- printf(" %d states, %d parser table entries, %d conflicts\n",
- lem.nstate, lem.tablesize, lem.nconflict);
- }
- if( lem.nconflict ){
- fprintf(stderr,"%d parsing conflicts.\n",lem.nconflict);
- }
- exit(lem.errorcnt + lem.nconflict);
-}
-/******************** From the file "msort.c" *******************************/
-/*
-** A generic merge-sort program.
-**
-** USAGE:
-** Let "ptr" be a pointer to some structure which is at the head of
-** a null-terminated list. Then to sort the list call:
-**
-** ptr = msort(ptr,&(ptr->next),cmpfnc);
-**
-** In the above, "cmpfnc" is a pointer to a function which compares
-** two instances of the structure and returns an integer, as in
-** strcmp. The second argument is a pointer to the pointer to the
-** second element of the linked list. This address is used to compute
-** the offset to the "next" field within the structure. The offset to
-** the "next" field must be constant for all structures in the list.
-**
-** The function returns a new pointer which is the head of the list
-** after sorting.
-**
-** ALGORITHM:
-** Merge-sort.
-*/
-
-/*
-** Return a pointer to the next structure in the linked list.
-*/
-#define NEXT(A) (*(char**)(((char *)A)+offset))
-
-/*
-** Inputs:
-** a: A sorted, null-terminated linked list. (May be null).
-** b: A sorted, null-terminated linked list. (May be null).
-** cmp: A pointer to the comparison function.
-** offset: Offset in the structure to the "next" field.
-**
-** Return Value:
-** A pointer to the head of a sorted list containing the elements
-** of both a and b.
-**
-** Side effects:
-** The "next" pointers for elements in the lists a and b are
-** changed.
-*/
-static char *merge(char *a, char *b, int (*cmp)(const void *, const void *),
- int offset)
-{
- char *ptr, *head;
-
- if( a==0 ){
- head = b;
- }else if( b==0 ){
- head = a;
- }else{
- if( (*cmp)(a,b)<0 ){
- ptr = a;
- a = NEXT(a);
- }else{
- ptr = b;
- b = NEXT(b);
- }
- head = ptr;
- while( a && b ){
- if( (*cmp)(a,b)<0 ){
- NEXT(ptr) = a;
- ptr = a;
- a = NEXT(a);
- }else{
- NEXT(ptr) = b;
- ptr = b;
- b = NEXT(b);
- }
- }
- if( a ) NEXT(ptr) = a;
- else NEXT(ptr) = b;
- }
- return head;
-}
-
-/*
-** Inputs:
-** list: Pointer to a singly-linked list of structures.
-** next: Pointer to pointer to the second element of the list.
-** cmp: A comparison function.
-**
-** Return Value:
-** A pointer to the head of a sorted list containing the elements
-** orginally in list.
-**
-** Side effects:
-** The "next" pointers for elements in list are changed.
-*/
-#define LISTSIZE 30
-char *msort(char *list, char **next, int (*cmp)(const void *, const void *))
-{
- int offset;
- char *ep;
- char *set[LISTSIZE];
- int i;
- offset = (char *)next - (char *)list;
- for(i=0; i<LISTSIZE; i++) set[i] = 0;
- while( list ){
- ep = list;
- list = NEXT(list);
- NEXT(ep) = 0;
- for(i=0; i<LISTSIZE-1 && set[i]!=0; i++){
- ep = merge(ep,set[i],cmp,offset);
- set[i] = 0;
- }
- set[i] = ep;
- }
- ep = 0;
- for(i=0; i<LISTSIZE; i++) if( set[i] ) ep = merge(ep,set[i],cmp,offset);
- return ep;
-}
-/************************ From the file "option.c" **************************/
-static char **argv;
-static struct s_options *op;
-static FILE *errstream;
-
-#define ISOPT(X) ((X)[0]=='-'||(X)[0]=='+'||strchr((X),'=')!=0)
-
-/*
-** Print the command line with a carrot pointing to the k-th character
-** of the n-th field.
-*/
-static void errline(int n, int k, FILE *err)
-{
- int spcnt, i;
- spcnt = 0;
- if( argv[0] ) fprintf(err,"%s",argv[0]);
- spcnt = strlen(argv[0]) + 1;
- for(i=1; i<n && argv[i]; i++){
- fprintf(err," %s",argv[i]);
- spcnt += strlen(argv[i]+1);
- }
- spcnt += k;
- for(; argv[i]; i++) fprintf(err," %s",argv[i]);
- if( spcnt<20 ){
- fprintf(err,"\n%*s^-- here\n",spcnt,"");
- }else{
- fprintf(err,"\n%*shere --^\n",spcnt-7,"");
- }
-}
-
-/*
-** Return the index of the N-th non-switch argument. Return -1
-** if N is out of range.
-*/
-static int argindex(int n)
-{
- int i;
- int dashdash = 0;
- if( argv!=0 && *argv!=0 ){
- for(i=1; argv[i]; i++){
- if( dashdash || !ISOPT(argv[i]) ){
- if( n==0 ) return i;
- n--;
- }
- if( strcmp(argv[i],"--")==0 ) dashdash = 1;
- }
- }
- return -1;
-}
-
-static char emsg[] = "Command line syntax error: ";
-
-/*
-** Process a flag command line argument.
-*/
-static int handleflags(int i, FILE *err)
-{
- int v;
- int errcnt = 0;
- int j;
- for(j=0; op[j].label; j++){
- if( strcmp(&argv[i][1],op[j].label)==0 ) break;
- }
- v = argv[i][0]=='-' ? 1 : 0;
- if( op[j].label==0 ){
- if( err ){
- fprintf(err,"%sundefined option.\n",emsg);
- errline(i,1,err);
- }
- errcnt++;
- }else if( op[j].type==OPT_FLAG ){
- *((int*)op[j].arg.val) = v;
- }else if( op[j].type==OPT_FFLAG ){
- op[j].arg.fflag(v);
- }else{
- if( err ){
- fprintf(err,"%smissing argument on switch.\n",emsg);
- errline(i,1,err);
- }
- errcnt++;
- }
- return errcnt;
-}
-
-/*
-** Process a command line switch which has an argument.
-*/
-static int handleswitch(int i, FILE *err)
-{
- int lv = 0;
- double dv = 0.0;
- char *sv = 0, *end;
- char *cp;
- int j;
- int errcnt = 0;
- cp = strchr(argv[i],'=');
- *cp = 0;
- for(j=0; op[j].label; j++){
- if( strcmp(argv[i],op[j].label)==0 ) break;
- }
- *cp = '=';
- if( op[j].label==0 ){
- if( err ){
- fprintf(err,"%sundefined option.\n",emsg);
- errline(i,0,err);
- }
- errcnt++;
- }else{
- cp++;
- switch( op[j].type ){
- case OPT_FLAG:
- case OPT_FFLAG:
- if( err ){
- fprintf(err,"%soption requires an argument.\n",emsg);
- errline(i,0,err);
- }
- errcnt++;
- break;
- case OPT_DBL:
- case OPT_FDBL:
- dv = strtod(cp,&end);
- if( *end ){
- if( err ){
- fprintf(err,"%sillegal character in floating-point argument.\n",emsg);
- errline(i,(int)(end-argv[i]),err);
- }
- errcnt++;
- }
- break;
- case OPT_INT:
- case OPT_FINT:
- lv = strtol(cp,&end,0);
- if( *end ){
- if( err ){
- fprintf(err,"%sillegal character in integer argument.\n",emsg);
- errline(i,(int)(end-argv[i]),err);
- }
- errcnt++;
- }
- break;
- case OPT_STR:
- case OPT_FSTR:
- sv = cp;
- break;
- }
- switch( op[j].type ){
- case OPT_FLAG:
- case OPT_FFLAG:
- break;
- case OPT_DBL:
- *(double*)(op[j].arg.val) = dv;
- break;
- case OPT_FDBL:
- op[j].arg.fdbl(dv);
- break;
- case OPT_INT:
- *(int*)(op[j].arg.val) = lv;
- break;
- case OPT_FINT:
- op[j].arg.fint(lv);
- break;
- case OPT_STR:
- *(char**)(op[j].arg.val) = sv;
- break;
- case OPT_FSTR:
- op[j].arg.fstr(sv);
- break;
- }
- }
- return errcnt;
-}
-
-int OptInit(char **a, struct s_options *o, FILE *err)
-{
- int errcnt = 0;
- argv = a;
- op = o;
- errstream = err;
- if( argv && *argv && op ){
- int i;
- for(i=1; argv[i]; i++){
- if( argv[i][0]=='+' || argv[i][0]=='-' ){
- errcnt += handleflags(i,err);
- }else if( strchr(argv[i],'=') ){
- errcnt += handleswitch(i,err);
- }
- }
- }
- if( errcnt>0 ){
- fprintf(err,"Valid command line options for \"%s\" are:\n",*a);
- OptPrint();
- exit(1);
- }
- return 0;
-}
-
-int OptNArgs(void){
- int cnt = 0;
- int dashdash = 0;
- int i;
- if( argv!=0 && argv[0]!=0 ){
- for(i=1; argv[i]; i++){
- if( dashdash || !ISOPT(argv[i]) ) cnt++;
- if( strcmp(argv[i],"--")==0 ) dashdash = 1;
- }
- }
- return cnt;
-}
-
-char *OptArg(int n)
-{
- int i;
- i = argindex(n);
- return i>=0 ? argv[i] : 0;
-}
-
-void OptErr(int n)
-{
- int i;
- i = argindex(n);
- if( i>=0 ) errline(i,0,errstream);
-}
-
-void OptPrint(void){
- int i;
- int max, len;
- max = 0;
- for(i=0; op[i].label; i++){
- len = strlen(op[i].label) + 1;
- switch( op[i].type ){
- case OPT_FLAG:
- case OPT_FFLAG:
- break;
- case OPT_INT:
- case OPT_FINT:
- len += 9; /* length of "<integer>" */
- break;
- case OPT_DBL:
- case OPT_FDBL:
- len += 6; /* length of "<real>" */
- break;
- case OPT_STR:
- case OPT_FSTR:
- len += 8; /* length of "<string>" */
- break;
- }
- if( len>max ) max = len;
- }
- for(i=0; op[i].label; i++){
- switch( op[i].type ){
- case OPT_FLAG:
- case OPT_FFLAG:
- fprintf(errstream," -%-*s %s\n",max,op[i].label,op[i].message);
- break;
- case OPT_INT:
- case OPT_FINT:
- fprintf(errstream," %s=<integer>%*s %s\n",op[i].label,
- (int)(max-strlen(op[i].label)-9),"",op[i].message);
- break;
- case OPT_DBL:
- case OPT_FDBL:
- fprintf(errstream," %s=<real>%*s %s\n",op[i].label,
- (int)(max-strlen(op[i].label)-6),"",op[i].message);
- break;
- case OPT_STR:
- case OPT_FSTR:
- fprintf(errstream," %s=<string>%*s %s\n",op[i].label,
- (int)(max-strlen(op[i].label)-8),"",op[i].message);
- break;
- }
- }
-}
-/*********************** From the file "parse.c" ****************************/
-/*
-** Input file parser for the LEMON parser generator.
-*/
-
-/* The state of the parser */
-struct pstate {
- char *filename; /* Name of the input file */
- int tokenlineno; /* Linenumber at which current token starts */
- int errorcnt; /* Number of errors so far */
- char *tokenstart; /* Text of current token */
- struct lemon *gp; /* Global state vector */
- enum e_state {
- INITIALIZE,
- WAITING_FOR_DECL_OR_RULE,
- WAITING_FOR_DECL_KEYWORD,
- WAITING_FOR_DECL_ARG,
- WAITING_FOR_PRECEDENCE_SYMBOL,
- WAITING_FOR_ARROW,
- IN_RHS,
- LHS_ALIAS_1,
- LHS_ALIAS_2,
- LHS_ALIAS_3,
- RHS_ALIAS_1,
- RHS_ALIAS_2,
- PRECEDENCE_MARK_1,
- PRECEDENCE_MARK_2,
- RESYNC_AFTER_RULE_ERROR,
- RESYNC_AFTER_DECL_ERROR,
- WAITING_FOR_DESTRUCTOR_SYMBOL,
- WAITING_FOR_DATATYPE_SYMBOL
- } state; /* The state of the parser */
- struct symbol *lhs; /* Left-hand side of current rule */
- char *lhsalias; /* Alias for the LHS */
- int nrhs; /* Number of right-hand side symbols seen */
- struct symbol *rhs[MAXRHS]; /* RHS symbols */
- char *alias[MAXRHS]; /* Aliases for each RHS symbol (or NULL) */
- struct rule *prevrule; /* Previous rule parsed */
- char *declkeyword; /* Keyword of a declaration */
- char **declargslot; /* Where the declaration argument should be put */
- int *decllnslot; /* Where the declaration linenumber is put */
- enum e_assoc declassoc; /* Assign this association to decl arguments */
- int preccounter; /* Assign this precedence to decl arguments */
- struct rule *firstrule; /* Pointer to first rule in the grammar */
- struct rule *lastrule; /* Pointer to the most recently parsed rule */
-};
-
-/* Parse a single token */
-static void parseonetoken(struct pstate *psp)
-{
- char *x;
- x = Strsafe(psp->tokenstart); /* Save the token permanently */
-#if 0
- printf("%s:%d: Token=[%s] state=%d\n",psp->filename,psp->tokenlineno,
- x,psp->state);
-#endif
- switch( psp->state ){
- case INITIALIZE:
- psp->prevrule = 0;
- psp->preccounter = 0;
- psp->firstrule = psp->lastrule = 0;
- psp->gp->nrule = 0;
- /* Fall thru to next case */
- case WAITING_FOR_DECL_OR_RULE:
- if( x[0]=='%' ){
- psp->state = WAITING_FOR_DECL_KEYWORD;
- }else if( safe_islower(x[0]) ){
- psp->lhs = Symbol_new(x);
- psp->nrhs = 0;
- psp->lhsalias = 0;
- psp->state = WAITING_FOR_ARROW;
- }else if( x[0]=='{' ){
- if( psp->prevrule==0 ){
- ErrorMsg(psp->filename,psp->tokenlineno,
-"There is not prior rule opon which to attach the code \
-fragment which begins on this line.");
- psp->errorcnt++;
- }else if( psp->prevrule->code!=0 ){
- ErrorMsg(psp->filename,psp->tokenlineno,
-"Code fragment beginning on this line is not the first \
-to follow the previous rule.");
- psp->errorcnt++;
- }else{
- psp->prevrule->line = psp->tokenlineno;
- psp->prevrule->code = &x[1];
- }
- }else if( x[0]=='[' ){
- psp->state = PRECEDENCE_MARK_1;
- }else{
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Token \"%s\" should be either \"%%\" or a nonterminal name.",
- x);
- psp->errorcnt++;
- }
- break;
- case PRECEDENCE_MARK_1:
- if( !safe_isupper(x[0]) ){
- ErrorMsg(psp->filename,psp->tokenlineno,
- "The precedence symbol must be a terminal.");
- psp->errorcnt++;
- }else if( psp->prevrule==0 ){
- ErrorMsg(psp->filename,psp->tokenlineno,
- "There is no prior rule to assign precedence \"[%s]\".",x);
- psp->errorcnt++;
- }else if( psp->prevrule->precsym!=0 ){
- ErrorMsg(psp->filename,psp->tokenlineno,
-"Precedence mark on this line is not the first \
-to follow the previous rule.");
- psp->errorcnt++;
- }else{
- psp->prevrule->precsym = Symbol_new(x);
- }
- psp->state = PRECEDENCE_MARK_2;
- break;
- case PRECEDENCE_MARK_2:
- if( x[0]!=']' ){
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Missing \"]\" on precedence mark.");
- psp->errorcnt++;
- }
- psp->state = WAITING_FOR_DECL_OR_RULE;
- break;
- case WAITING_FOR_ARROW:
- if( x[0]==':' && x[1]==':' && x[2]=='=' ){
- psp->state = IN_RHS;
- }else if( x[0]=='(' ){
- psp->state = LHS_ALIAS_1;
- }else{
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Expected to see a \":\" following the LHS symbol \"%s\".",
- psp->lhs->name);
- psp->errorcnt++;
- psp->state = RESYNC_AFTER_RULE_ERROR;
- }
- break;
- case LHS_ALIAS_1:
- if( safe_isalpha(x[0]) ){
- psp->lhsalias = x;
- psp->state = LHS_ALIAS_2;
- }else{
- ErrorMsg(psp->filename,psp->tokenlineno,
- "\"%s\" is not a valid alias for the LHS \"%s\"\n",
- x,psp->lhs->name);
- psp->errorcnt++;
- psp->state = RESYNC_AFTER_RULE_ERROR;
- }
- break;
- case LHS_ALIAS_2:
- if( x[0]==')' ){
- psp->state = LHS_ALIAS_3;
- }else{
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Missing \")\" following LHS alias name \"%s\".",psp->lhsalias);
- psp->errorcnt++;
- psp->state = RESYNC_AFTER_RULE_ERROR;
- }
- break;
- case LHS_ALIAS_3:
- if( x[0]==':' && x[1]==':' && x[2]=='=' ){
- psp->state = IN_RHS;
- }else{
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Missing \"->\" following: \"%s(%s)\".",
- psp->lhs->name,psp->lhsalias);
- psp->errorcnt++;
- psp->state = RESYNC_AFTER_RULE_ERROR;
- }
- break;
- case IN_RHS:
- if( x[0]=='.' ){
- struct rule *rp;
- rp = (struct rule *)malloc( sizeof(struct rule) +
- sizeof(struct symbol*)*psp->nrhs + sizeof(char*)*psp->nrhs );
- if( rp==0 ){
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Can't allocate enough memory for this rule.");
- psp->errorcnt++;
- psp->prevrule = 0;
- }else{
- int i;
- rp->ruleline = psp->tokenlineno;
- rp->rhs = (struct symbol**)&rp[1];
- rp->rhsalias = (char**)&(rp->rhs[psp->nrhs]);
- for(i=0; i<psp->nrhs; i++){
- rp->rhs[i] = psp->rhs[i];
- rp->rhsalias[i] = psp->alias[i];
- }
- rp->lhs = psp->lhs;
- rp->lhsalias = psp->lhsalias;
- rp->nrhs = psp->nrhs;
- rp->code = 0;
- rp->precsym = 0;
- rp->index = psp->gp->nrule++;
- rp->nextlhs = rp->lhs->rule;
- rp->lhs->rule = rp;
- rp->next = 0;
- if( psp->firstrule==0 ){
- psp->firstrule = psp->lastrule = rp;
- }else{
- psp->lastrule->next = rp;
- psp->lastrule = rp;
- }
- psp->prevrule = rp;
- }
- psp->state = WAITING_FOR_DECL_OR_RULE;
- }else if( safe_isalpha(x[0]) ){
- if( psp->nrhs>=MAXRHS ){
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Too many symbol on RHS or rule beginning at \"%s\".",
- x);
- psp->errorcnt++;
- psp->state = RESYNC_AFTER_RULE_ERROR;
- }else{
- psp->rhs[psp->nrhs] = Symbol_new(x);
- psp->alias[psp->nrhs] = 0;
- psp->nrhs++;
- }
- }else if( x[0]=='(' && psp->nrhs>0 ){
- psp->state = RHS_ALIAS_1;
- }else{
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Illegal character on RHS of rule: \"%s\".",x);
- psp->errorcnt++;
- psp->state = RESYNC_AFTER_RULE_ERROR;
- }
- break;
- case RHS_ALIAS_1:
- if( safe_isalpha(x[0]) ){
- psp->alias[psp->nrhs-1] = x;
- psp->state = RHS_ALIAS_2;
- }else{
- ErrorMsg(psp->filename,psp->tokenlineno,
- "\"%s\" is not a valid alias for the RHS symbol \"%s\"\n",
- x,psp->rhs[psp->nrhs-1]->name);
- psp->errorcnt++;
- psp->state = RESYNC_AFTER_RULE_ERROR;
- }
- break;
- case RHS_ALIAS_2:
- if( x[0]==')' ){
- psp->state = IN_RHS;
- }else{
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Missing \")\" following LHS alias name \"%s\".",psp->lhsalias);
- psp->errorcnt++;
- psp->state = RESYNC_AFTER_RULE_ERROR;
- }
- break;
- case WAITING_FOR_DECL_KEYWORD:
- if( safe_isalpha(x[0]) ){
- psp->declkeyword = x;
- psp->declargslot = 0;
- psp->decllnslot = 0;
- psp->state = WAITING_FOR_DECL_ARG;
- if( strcmp(x,"name")==0 ){
- psp->declargslot = &(psp->gp->name);
- }else if( strcmp(x,"include")==0 ){
- psp->declargslot = &(psp->gp->include);
- psp->decllnslot = &psp->gp->includeln;
- }else if( strcmp(x,"code")==0 ){
- psp->declargslot = &(psp->gp->extracode);
- psp->decllnslot = &psp->gp->extracodeln;
- }else if( strcmp(x,"token_destructor")==0 ){
- psp->declargslot = &psp->gp->tokendest;
- psp->decllnslot = &psp->gp->tokendestln;
- }else if( strcmp(x,"token_prefix")==0 ){
- psp->declargslot = &psp->gp->tokenprefix;
- }else if( strcmp(x,"syntax_error")==0 ){
- psp->declargslot = &(psp->gp->error);
- psp->decllnslot = &psp->gp->errorln;
- }else if( strcmp(x,"parse_accept")==0 ){
- psp->declargslot = &(psp->gp->accept);
- psp->decllnslot = &psp->gp->acceptln;
- }else if( strcmp(x,"parse_failure")==0 ){
- psp->declargslot = &(psp->gp->failure);
- psp->decllnslot = &psp->gp->failureln;
- }else if( strcmp(x,"stack_overflow")==0 ){
- psp->declargslot = &(psp->gp->overflow);
- psp->decllnslot = &psp->gp->overflowln;
- }else if( strcmp(x,"extra_argument")==0 ){
- psp->declargslot = &(psp->gp->arg);
- }else if( strcmp(x,"token_type")==0 ){
- psp->declargslot = &(psp->gp->tokentype);
- }else if( strcmp(x,"stack_size")==0 ){
- psp->declargslot = &(psp->gp->stacksize);
- }else if( strcmp(x,"start_symbol")==0 ){
- psp->declargslot = &(psp->gp->start);
- }else if( strcmp(x,"left")==0 ){
- psp->preccounter++;
- psp->declassoc = LEFT;
- psp->state = WAITING_FOR_PRECEDENCE_SYMBOL;
- }else if( strcmp(x,"right")==0 ){
- psp->preccounter++;
- psp->declassoc = RIGHT;
- psp->state = WAITING_FOR_PRECEDENCE_SYMBOL;
- }else if( strcmp(x,"nonassoc")==0 ){
- psp->preccounter++;
- psp->declassoc = NONE;
- psp->state = WAITING_FOR_PRECEDENCE_SYMBOL;
- }else if( strcmp(x,"destructor")==0 ){
- psp->state = WAITING_FOR_DESTRUCTOR_SYMBOL;
- }else if( strcmp(x,"type")==0 ){
- psp->state = WAITING_FOR_DATATYPE_SYMBOL;
- }else{
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Unknown declaration keyword: \"%%%s\".",x);
- psp->errorcnt++;
- psp->state = RESYNC_AFTER_DECL_ERROR;
- }
- }else{
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Illegal declaration keyword: \"%s\".",x);
- psp->errorcnt++;
- psp->state = RESYNC_AFTER_DECL_ERROR;
- }
- break;
- case WAITING_FOR_DESTRUCTOR_SYMBOL:
- if( !safe_isalpha(x[0]) ){
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Symbol name missing after %%destructor keyword");
- psp->errorcnt++;
- psp->state = RESYNC_AFTER_DECL_ERROR;
- }else{
- struct symbol *sp = Symbol_new(x);
- psp->declargslot = &sp->destructor;
- psp->decllnslot = &sp->destructorln;
- psp->state = WAITING_FOR_DECL_ARG;
- }
- break;
- case WAITING_FOR_DATATYPE_SYMBOL:
- if( !safe_isalpha(x[0]) ){
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Symbol name missing after %%destructor keyword");
- psp->errorcnt++;
- psp->state = RESYNC_AFTER_DECL_ERROR;
- }else{
- struct symbol *sp = Symbol_new(x);
- psp->declargslot = &sp->datatype;
- psp->decllnslot = 0;
- psp->state = WAITING_FOR_DECL_ARG;
- }
- break;
- case WAITING_FOR_PRECEDENCE_SYMBOL:
- if( x[0]=='.' ){
- psp->state = WAITING_FOR_DECL_OR_RULE;
- }else if( safe_isupper(x[0]) ){
- struct symbol *sp;
- sp = Symbol_new(x);
- if( sp->prec>=0 ){
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Symbol \"%s\" has already be given a precedence.",x);
- psp->errorcnt++;
- }else{
- sp->prec = psp->preccounter;
- sp->assoc = psp->declassoc;
- }
- }else{
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Can't assign a precedence to \"%s\".",x);
- psp->errorcnt++;
- }
- break;
- case WAITING_FOR_DECL_ARG:
- if( (x[0]=='{' || x[0]=='\"' || safe_isalnum(x[0])) ){
- if( *(psp->declargslot)!=0 ){
- ErrorMsg(psp->filename,psp->tokenlineno,
- "The argument \"%s\" to declaration \"%%%s\" is not the first.",
- x[0]=='\"' ? &x[1] : x,psp->declkeyword);
- psp->errorcnt++;
- psp->state = RESYNC_AFTER_DECL_ERROR;
- }else{
- *(psp->declargslot) = (x[0]=='\"' || x[0]=='{') ? &x[1] : x;
- if( psp->decllnslot ) *psp->decllnslot = psp->tokenlineno;
- psp->state = WAITING_FOR_DECL_OR_RULE;
- }
- }else{
- ErrorMsg(psp->filename,psp->tokenlineno,
- "Illegal argument to %%%s: %s",psp->declkeyword,x);
- psp->errorcnt++;
- psp->state = RESYNC_AFTER_DECL_ERROR;
- }
- break;
- case RESYNC_AFTER_RULE_ERROR:
-/* if( x[0]=='.' ) psp->state = WAITING_FOR_DECL_OR_RULE;
-** break; */
- case RESYNC_AFTER_DECL_ERROR:
- if( x[0]=='.' ) psp->state = WAITING_FOR_DECL_OR_RULE;
- if( x[0]=='%' ) psp->state = WAITING_FOR_DECL_KEYWORD;
- break;
- }
-}
-
-/* In spite of its name, this function is really a scanner. It read
-** in the entire input file (all at once) then tokenizes it. Each
-** token is passed to the function "parseonetoken" which builds all
-** the appropriate data structures in the global state vector "gp".
-*/
-void Parse(struct lemon *gp)
-{
- struct pstate ps;
- FILE *fp;
- char *filebuf;
- long filesize;
- int lineno;
- char c;
- char *cp, *nextcp;
- int startline = 0;
-
- ps.gp = gp;
- ps.filename = gp->filename;
- ps.errorcnt = 0;
- ps.state = INITIALIZE;
-
- /* Begin by reading the input file */
- fp = fopen(ps.filename,"rb");
- if( fp==0 ){
- ErrorMsg(ps.filename,0,"Can't open this file for reading.");
- gp->errorcnt++;
- return;
- }
- fseek(fp,0,2);
- filesize = ftell(fp);
- rewind(fp);
- /* XXX - what if filesize is bigger than the maximum size_t value? */
- filebuf = (char *)malloc( filesize+1 );
- if( filebuf==0 ){
- ErrorMsg(ps.filename,0,"Can't allocate %ld of memory to hold this file.",
- filesize+1);
- gp->errorcnt++;
- return;
- }
- if( fread(filebuf,1,filesize,fp)!=(size_t)filesize ){
- ErrorMsg(ps.filename,0,"Can't read in all %ld bytes of this file.",
- filesize);
- free(filebuf);
- gp->errorcnt++;
- return;
- }
- fclose(fp);
- filebuf[filesize] = 0;
-
- /* Now scan the text of the input file */
- lineno = 1;
- for(cp=filebuf; (c= *cp)!=0; ){
- if( c=='\n' ) lineno++; /* Keep track of the line number */
- if( safe_isspace(c) ){ cp++; continue; } /* Skip all white space */
- if( c=='/' && cp[1]=='/' ){ /* Skip C++ style comments */
- cp+=2;
- while( (c= *cp)!=0 && c!='\n' ) cp++;
- continue;
- }
- if( c=='/' && cp[1]=='*' ){ /* Skip C style comments */
- cp+=2;
- while( (c= *cp)!=0 && (c!='/' || cp[-1]!='*') ){
- if( c=='\n' ) lineno++;
- cp++;
- }
- if( c ) cp++;
- continue;
- }
- ps.tokenstart = cp; /* Mark the beginning of the token */
- ps.tokenlineno = lineno; /* Linenumber on which token begins */
- if( c=='\"' ){ /* String literals */
- cp++;
- while( (c= *cp)!=0 && c!='\"' ){
- if( c=='\n' ) lineno++;
- cp++;
- }
- if( c==0 ){
- ErrorMsg(ps.filename,startline,
-"String starting on this line is not terminated before the end of the file.");
- ps.errorcnt++;
- nextcp = cp;
- }else{
- nextcp = cp+1;
- }
- }else if( c=='{' ){ /* A block of C code */
- int level;
- cp++;
- for(level=1; (c= *cp)!=0 && (level>1 || c!='}'); cp++){
- if( c=='\n' ) lineno++;
- else if( c=='{' ) level++;
- else if( c=='}' ) level--;
- else if( c=='/' && cp[1]=='*' ){ /* Skip comments */
- char prevc;
- cp = &cp[2];
- prevc = 0;
- while( (c= *cp)!=0 && (c!='/' || prevc!='*') ){
- if( c=='\n' ) lineno++;
- prevc = c;
- cp++;
- }
- }else if( c=='/' && cp[1]=='/' ){ /* Skip C++ style comments too */
- cp = &cp[2];
- while( (c= *cp)!=0 && c!='\n' ) cp++;
- if( c ) lineno++;
- }else if( c=='\'' || c=='\"' ){ /* String a character literals */
- char startchar, prevc;
- startchar = c;
- prevc = 0;
- for(cp++; (c= *cp)!=0 && (c!=startchar || prevc=='\\'); cp++){
- if( c=='\n' ) lineno++;
- if( prevc=='\\' ) prevc = 0;
- else prevc = c;
- }
- }
- }
- if( c==0 ){
- ErrorMsg(ps.filename,ps.tokenlineno,
-"C code starting on this line is not terminated before the end of the file.");
- ps.errorcnt++;
- nextcp = cp;
- }else{
- nextcp = cp+1;
- }
- }else if( safe_isalnum(c) ){ /* Identifiers */
- while( (c= *cp)!=0 && (safe_isalnum(c) || c=='_') ) cp++;
- nextcp = cp;
- }else if( c==':' && cp[1]==':' && cp[2]=='=' ){ /* The operator "::=" */
- cp += 3;
- nextcp = cp;
- }else{ /* All other (one character) operators */
- cp++;
- nextcp = cp;
- }
- c = *cp;
- *cp = 0; /* Null terminate the token */
- parseonetoken(&ps); /* Parse the token */
- *cp = c; /* Restore the buffer */
- cp = nextcp;
- }
- free(filebuf); /* Release the buffer after parsing */
- gp->rule = ps.firstrule;
- gp->errorcnt = ps.errorcnt;
-}
-/*************************** From the file "plink.c" *********************/
-/*
-** Routines processing configuration follow-set propagation links
-** in the LEMON parser generator.
-*/
-static struct plink *plink_freelist = 0;
-
-/* Allocate a new plink */
-struct plink *Plink_new(void){
- struct plink *new;
-
- if( plink_freelist==0 ){
- int i;
- int amt = 100;
- plink_freelist = (struct plink *)malloc( sizeof(struct plink)*amt );
- if( plink_freelist==0 ){
- fprintf(stderr,
- "Unable to allocate memory for a new follow-set propagation link.\n");
- exit(1);
- }
- for(i=0; i<amt-1; i++) plink_freelist[i].next = &plink_freelist[i+1];
- plink_freelist[amt-1].next = 0;
- }
- new = plink_freelist;
- plink_freelist = plink_freelist->next;
- return new;
-}
-
-/* Add a plink to a plink list */
-void Plink_add(struct plink **plpp, struct config *cfp)
-{
- struct plink *new;
- new = Plink_new();
- new->next = *plpp;
- *plpp = new;
- new->cfp = cfp;
-}
-
-/* Transfer every plink on the list "from" to the list "to" */
-void Plink_copy(struct plink **to, struct plink *from)
-{
- struct plink *nextpl;
- while( from ){
- nextpl = from->next;
- from->next = *to;
- *to = from;
- from = nextpl;
- }
-}
-
-/* Delete every plink on the list */
-void Plink_delete(struct plink *plp)
-{
- struct plink *nextpl;
-
- while( plp ){
- nextpl = plp->next;
- plp->next = plink_freelist;
- plink_freelist = plp;
- plp = nextpl;
- }
-}
-
-/*********************** From the file "report.c" **************************/
-/*
-** Procedures for generating reports and tables in the LEMON parser generator.
-*/
-
-PRIVATE char *file_makename(struct lemon *, const char *);
-PRIVATE FILE *file_open(struct lemon *, const char *, const char *);
-void ConfigPrint(FILE *, struct config *);
-int PrintAction(struct action *, FILE *, int);
-PRIVATE const char *pathsearch(void);
-PRIVATE int compute_action(struct lemon *, struct action *);
-PRIVATE void tplt_xfer(char *, FILE *, FILE *, int *);
-PRIVATE FILE *tplt_open(struct lemon *);
-PRIVATE void tplt_print(FILE *, struct lemon *, char *, int, int *);
-void emit_destructor_code(FILE *, struct symbol *, struct lemon *, int *);
-int has_destructor(struct symbol *, struct lemon *);
-PRIVATE void emit_code(FILE *, struct rule *, struct lemon *, int *);
-void print_stack_union(FILE *, struct lemon *, int *, int);
-
-/* Generate a filename with the given suffix. Space to hold the
-** name comes from malloc() and must be freed by the calling
-** function.
-*/
-PRIVATE char *file_makename(struct lemon *lemp, const char *suffix)
-{
- char *name = NULL;
- char *cp, *fname;
-
- fname = output_file ? output_file : lemp->filename;
- name = malloc( strlen(fname) + strlen(suffix));
- if( name==0 ){
- fprintf(stderr,"Can't allocate space for a filename.\n");
- exit(1);
- }
- strcpy(name, fname);
- cp = strrchr(name,'.');
- if( cp ) *cp = 0;
- strcat(name,suffix);
- return name;
-}
-
-/* Open a file with a name based on the name of the input file,
-** but with a different (specified) suffix, and return a pointer
-** to the stream */
-PRIVATE FILE *file_open(struct lemon *lemp, const char *suffix,
- const char *mode)
-{
- FILE *fp;
-
- if( lemp->outname ) free(lemp->outname);
- lemp->outname = file_makename(lemp, suffix);
- fp = fopen(lemp->outname,mode);
- if( fp==0 && *mode=='w' ){
- fprintf(stderr,"Can't open file \"%s\".\n",lemp->outname);
- lemp->errorcnt++;
- return 0;
- }
- return fp;
-}
-
-/* Duplicate the input file without comments and without actions
-** on rules */
-void Reprint(struct lemon *lemp)
-{
- struct rule *rp;
- struct symbol *sp;
- int i, j, maxlen, len, ncolumns, skip;
- printf("// Reprint of input file \"%s\".\n// Symbols:\n",lemp->filename);
- maxlen = 10;
- for(i=0; i<lemp->nsymbol; i++){
- sp = lemp->symbols[i];
- len = strlen(sp->name);
- if( len>maxlen ) maxlen = len;
- }
- ncolumns = 76/(maxlen+5);
- if( ncolumns<1 ) ncolumns = 1;
- skip = (lemp->nsymbol + ncolumns - 1)/ncolumns;
- for(i=0; i<skip; i++){
- printf("//");
- for(j=i; j<lemp->nsymbol; j+=skip){
- sp = lemp->symbols[j];
- assert( sp->index==j );
- printf(" %3d %-*.*s",j,maxlen,maxlen,sp->name);
- }
- printf("\n");
- }
- for(rp=lemp->rule; rp; rp=rp->next){
- printf("%s",rp->lhs->name);
-/* if( rp->lhsalias ) printf("(%s)",rp->lhsalias); */
- printf(" ::=");
- for(i=0; i<rp->nrhs; i++){
- printf(" %s",rp->rhs[i]->name);
-/* if( rp->rhsalias[i] ) printf("(%s)",rp->rhsalias[i]); */
- }
- printf(".");
- if( rp->precsym ) printf(" [%s]",rp->precsym->name);
-/* if( rp->code ) printf("\n %s",rp->code); */
- printf("\n");
- }
-}
-
-void ConfigPrint(FILE *fp, struct config *cfp)
-{
- struct rule *rp;
- int i;
- rp = cfp->rp;
- fprintf(fp,"%s ::=",rp->lhs->name);
- for(i=0; i<=rp->nrhs; i++){
- if( i==cfp->dot ) fprintf(fp," *");
- if( i==rp->nrhs ) break;
- fprintf(fp," %s",rp->rhs[i]->name);
- }
-}
-
-/* #define TEST */
-#ifdef TEST
-/* Print a set */
-PRIVATE void SetPrint(FILE *out, char *set, struct lemon *lemp)
-{
- int i;
- char *spacer;
- spacer = "";
- fprintf(out,"%12s[","");
- for(i=0; i<lemp->nterminal; i++){
- if( SetFind(set,i) ){
- fprintf(out,"%s%s",spacer,lemp->symbols[i]->name);
- spacer = " ";
- }
- }
- fprintf(out,"]\n");
-}
-
-/* Print a plink chain */
-PRIVATE void PlinkPrint(FILE *out, struct plink *plp, char *tag)
-{
- while( plp ){
- fprintf(out,"%12s%s (state %2d) ","",tag,plp->cfp->stp->index);
- ConfigPrint(out,plp->cfp);
- fprintf(out,"\n");
- plp = plp->next;
- }
-}
-#endif
-
-/* Print an action to the given file descriptor. Return FALSE if
-** nothing was actually printed.
-*/
-int PrintAction(struct action *ap, FILE *fp, int indent){
- int result = 1;
- switch( ap->type ){
- case SHIFT:
- fprintf(fp,"%*s shift %d",indent,ap->sp->name,ap->x.stp->index);
- break;
- case REDUCE:
- fprintf(fp,"%*s reduce %d",indent,ap->sp->name,ap->x.rp->index);
- break;
- case ACCEPT:
- fprintf(fp,"%*s accept",indent,ap->sp->name);
- break;
- case ERROR:
- fprintf(fp,"%*s error",indent,ap->sp->name);
- break;
- case CONFLICT:
- fprintf(fp,"%*s reduce %-3d ** Parsing conflict **",
- indent,ap->sp->name,ap->x.rp->index);
- break;
- case SH_RESOLVED:
- case RD_RESOLVED:
- case NOT_USED:
- result = 0;
- break;
- }
- return result;
-}
-
-/* Generate the "y.output" log file */
-void ReportOutput(struct lemon *lemp)
-{
- int i;
- struct state *stp;
- struct config *cfp;
- struct action *ap;
- FILE *fp;
-
- fp = file_open(lemp,".out","w");
- if( fp==0 ) return;
- fprintf(fp," \b");
- for(i=0; i<lemp->nstate; i++){
- stp = lemp->sorted[i];
- fprintf(fp,"State %d:\n",stp->index);
- if( lemp->basisflag ) cfp=stp->bp;
- else cfp=stp->cfp;
- while( cfp ){
- char buf[20];
- if( cfp->dot==cfp->rp->nrhs ){
- sprintf(buf,"(%d)",cfp->rp->index);
- fprintf(fp," %5s ",buf);
- }else{
- fprintf(fp," ");
- }
- ConfigPrint(fp,cfp);
- fprintf(fp,"\n");
-#ifdef TEST
- SetPrint(fp,cfp->fws,lemp);
- PlinkPrint(fp,cfp->fplp,"To ");
- PlinkPrint(fp,cfp->bplp,"From");
-#endif
- if( lemp->basisflag ) cfp=cfp->bp;
- else cfp=cfp->next;
- }
- fprintf(fp,"\n");
- for(ap=stp->ap; ap; ap=ap->next){
- if( PrintAction(ap,fp,30) ) fprintf(fp,"\n");
- }
- fprintf(fp,"\n");
- }
- fclose(fp);
- return;
-}
-
-PRIVATE const char *pathsearch(void)
-{
- int i;
-
- for (i = 0; i < sizeof(lempar_locations)/sizeof(char *); i++)
- if (lempar_locations[i] && access(lempar_locations[i], 004) == 0)
- return lempar_locations[i];
-
- return(NULL);
-}
-
-/* Given an action, compute the integer value for that action
-** which is to be put in the action table of the generated machine.
-** Return negative if no action should be generated.
-*/
-PRIVATE int compute_action(struct lemon *lemp, struct action *ap)
-{
- int act;
- switch( ap->type ){
- case SHIFT: act = ap->x.stp->index; break;
- case REDUCE: act = ap->x.rp->index + lemp->nstate; break;
- case ERROR: act = lemp->nstate + lemp->nrule; break;
- case ACCEPT: act = lemp->nstate + lemp->nrule + 1; break;
- default: act = -1; break;
- }
- return act;
-}
-
-#define LINESIZE 1000
-/* The next cluster of routines are for reading the template file
-** and writing the results to the generated parser */
-/* The first function transfers data from "in" to "out" until
-** a line is seen which begins with "%%". The line number is
-** tracked.
-**
-** if name!=0, then any word that begin with "Parse" is changed to
-** begin with *name instead.
-*/
-PRIVATE void tplt_xfer(char *name, FILE *in, FILE *out, int *lineno)
-{
- int i, iStart;
- char line[LINESIZE];
- while( fgets(line,LINESIZE,in) && (line[0]!='%' || line[1]!='%') ){
- (*lineno)++;
- iStart = 0;
- if( name ){
- for(i=0; line[i]; i++){
- if( line[i]=='P' && strncmp(&line[i],"Parse",5)==0
- && (i==0 || !safe_isalpha(line[i-1]))
- ){
- if( i>iStart ) fprintf(out,"%.*s",i-iStart,&line[iStart]);
- fprintf(out,"%s",name);
- i += 4;
- iStart = i+1;
- }
- }
- }
- fprintf(out,"%s",&line[iStart]);
- }
-}
-
-/* The next function finds the template file and opens it, returning
-** a pointer to the opened file. */
-PRIVATE FILE *tplt_open(struct lemon *lemp)
-{
- char buf[1000];
- FILE *in;
- const char *tpltname;
- char *cp;
-
- cp = strrchr(lemp->filename,'.');
- if( cp ){
- sprintf(buf,"%.*s.lt",(int)cp-(int)lemp->filename,lemp->filename);
- }else{
- sprintf(buf,"%s.lt",lemp->filename);
- }
- if( access(buf,004)==0 ){
- tpltname = buf;
- }else{
- tpltname = pathsearch();
- }
- if( tpltname==0 ){
- fprintf(stderr,"Can't find the parser driver template file.\n");
- lemp->errorcnt++;
- return 0;
- }
- in = fopen(tpltname,"r");
- if( in==0 ){
- fprintf(stderr,"Can't open the template file \"%s\".\n", tpltname);
- lemp->errorcnt++;
- return 0;
- }
- return in;
-}
-
-/* Print a string to the file and keep the linenumber up to date */
-PRIVATE void tplt_print(FILE *out, struct lemon *lemp, char *str,
- int strln, int *lineno)
-{
- if( str==0 ) return;
- fprintf(out,"#line %d \"%s\"\n",strln,lemp->filename); (*lineno)++;
- while( *str ){
- if( *str=='\n' ) (*lineno)++;
- putc(*str,out);
- str++;
- }
- fprintf(out,"\n#line %d \"%s\"\n",*lineno+2,lemp->outname); (*lineno)+=2;
- return;
-}
-
-/*
-** The following routine emits code for the destructor for the
-** symbol sp
-*/
-void emit_destructor_code(FILE *out, struct symbol *sp, struct lemon *lemp,
- int *lineno)
-{
- char *cp;
-
- int linecnt = 0;
- if( sp->type==TERMINAL ){
- cp = lemp->tokendest;
- if( cp==0 ) return;
- fprintf(out,"#line %d \"%s\"\n{",lemp->tokendestln,lemp->filename);
- }else{
- cp = sp->destructor;
- if( cp==0 ) return;
- fprintf(out,"#line %d \"%s\"\n{",sp->destructorln,lemp->filename);
- }
- for(; *cp; cp++){
- if( *cp=='$' && cp[1]=='$' ){
- fprintf(out,"(yypminor->yy%d)",sp->dtnum);
- cp++;
- continue;
- }
- if( *cp=='\n' ) linecnt++;
- fputc(*cp,out);
- }
- (*lineno) += 3 + linecnt;
- fprintf(out,"}\n#line %d \"%s\"\n",*lineno,lemp->outname);
- return;
-}
-
-/*
-** Return TRUE (non-zero) if the given symbol has a distructor.
-*/
-int has_destructor(struct symbol *sp, struct lemon *lemp)
-{
- int ret;
- if( sp->type==TERMINAL ){
- ret = lemp->tokendest!=0;
- }else{
- ret = sp->destructor!=0;
- }
- return ret;
-}
-
-/*
-** Generate code which executes when the rule "rp" is reduced. Write
-** the code to "out". Make sure lineno stays up-to-date.
-*/
-PRIVATE void emit_code(FILE *out, struct rule *rp, struct lemon *lemp,
- int *lineno)
-{
- char *cp, *xp;
- int linecnt = 0;
- int i;
- char lhsused = 0; /* True if the LHS element has been used */
- char used[MAXRHS]; /* True for each RHS element which is used */
-
- for(i=0; i<rp->nrhs; i++) used[i] = 0;
- lhsused = 0;
-
- /* Generate code to do the reduce action */
- if( rp->code ){
- fprintf(out,"#line %d \"%s\"\n{",rp->line,lemp->filename);
- for(cp=rp->code; *cp; cp++){
- if( safe_isalpha(*cp) && (cp==rp->code || !safe_isalnum(cp[-1])) ){
- char saved;
- for(xp= &cp[1]; safe_isalnum(*xp); xp++);
- saved = *xp;
- *xp = 0;
- if( rp->lhsalias && strcmp(cp,rp->lhsalias)==0 ){
- fprintf(out,"yygotominor.yy%d",rp->lhs->dtnum);
- cp = xp;
- lhsused = 1;
- }else{
- for(i=0; i<rp->nrhs; i++){
- if( rp->rhsalias[i] && strcmp(cp,rp->rhsalias[i])==0 ){
- fprintf(out,"yymsp[%d].minor.yy%d",i-rp->nrhs+1,rp->rhs[i]->dtnum);
- cp = xp;
- used[i] = 1;
- break;
- }
- }
- }
- *xp = saved;
- }
- if( *cp=='\n' ) linecnt++;
- fputc(*cp,out);
- } /* End loop */
- (*lineno) += 3 + linecnt;
- fprintf(out,"}\n#line %d \"%s\"\n",*lineno,lemp->outname);
- } /* End if( rp->code ) */
-
- /* Check to make sure the LHS has been used */
- if( rp->lhsalias && !lhsused ){
- ErrorMsg(lemp->filename,rp->ruleline,
- "Label \"%s\" for \"%s(%s)\" is never used.",
- rp->lhsalias,rp->lhs->name,rp->lhsalias);
- lemp->errorcnt++;
- }
-
- /* Generate destructor code for RHS symbols which are not used in the
- ** reduce code */
- for(i=0; i<rp->nrhs; i++){
- if( rp->rhsalias[i] && !used[i] ){
- ErrorMsg(lemp->filename,rp->ruleline,
- "Label $%s$ for \"%s(%s)\" is never used.",
- rp->rhsalias[i],rp->rhs[i]->name,rp->rhsalias[i]);
- lemp->errorcnt++;
- }else if( rp->rhsalias[i]==0 ){
- if( has_destructor(rp->rhs[i],lemp) ){
- fprintf(out," yy_destructor(%d,&yymsp[%d].minor);\n",
- rp->rhs[i]->index,i-rp->nrhs+1); (*lineno)++;
- }else{
- fprintf(out," /* No destructor defined for %s */\n",
- rp->rhs[i]->name);
- (*lineno)++;
- }
- }
- }
- return;
-}
-
-/*
-** Print the definition of the union used for the parser's data stack.
-** This union contains fields for every possible data type for tokens
-** and nonterminals. In the process of computing and printing this
-** union, also set the ".dtnum" field of every terminal and nonterminal
-** symbol.
-*/
-void print_stack_union(
- FILE *out, /* The output stream */
- struct lemon *lemp, /* The main info structure for this parser */
- int *plineno, /* Pointer to the line number */
- int mhflag) /* True if generating makeheaders output */
-{
- int lineno = *plineno; /* The line number of the output */
- char **types; /* A hash table of datatypes */
- int arraysize; /* Size of the "types" array */
- int maxdtlength; /* Maximum length of any ".datatype" field. */
- char *stddt; /* Standardized name for a datatype */
- int i,j; /* Loop counters */
- int hash; /* For hashing the name of a type */
- const char *name; /* Name of the parser */
-
- /* Allocate and initialize types[] and allocate stddt[] */
- arraysize = lemp->nsymbol * 2;
- types = (char**)malloc( arraysize * sizeof(char*) );
- for(i=0; i<arraysize; i++) types[i] = 0;
- maxdtlength = 0;
- for(i=0; i<lemp->nsymbol; i++){
- int len;
- struct symbol *sp = lemp->symbols[i];
- if( sp->datatype==0 ) continue;
- len = strlen(sp->datatype);
- if( len>maxdtlength ) maxdtlength = len;
- }
- stddt = (char*)malloc( maxdtlength*2 + 1 );
- if( types==0 || stddt==0 ){
- fprintf(stderr,"Out of memory.\n");
- exit(1);
- }
-
- /* Build a hash table of datatypes. The ".dtnum" field of each symbol
- ** is filled in with the hash index plus 1. A ".dtnum" value of 0 is
- ** used for terminal symbols and for nonterminals which don't specify
- ** a datatype using the %type directive. */
- for(i=0; i<lemp->nsymbol; i++){
- struct symbol *sp = lemp->symbols[i];
- char *cp;
- if( sp==lemp->errsym ){
- sp->dtnum = arraysize+1;
- continue;
- }
- if( sp->type!=NONTERMINAL || sp->datatype==0 ){
- sp->dtnum = 0;
- continue;
- }
- cp = sp->datatype;
- j = 0;
- while( safe_isspace(*cp) ) cp++;
- while( *cp ) stddt[j++] = *cp++;
- while( j>0 && safe_isspace(stddt[j-1]) ) j--;
- stddt[j] = 0;
- hash = 0;
- for(j=0; stddt[j]; j++){
- hash = hash*53 + stddt[j];
- }
- if( hash<0 ) hash = -hash;
- hash = hash%arraysize;
- while( types[hash] ){
- if( strcmp(types[hash],stddt)==0 ){
- sp->dtnum = hash + 1;
- break;
- }
- hash++;
- if( hash>=arraysize ) hash = 0;
- }
- if( types[hash]==0 ){
- sp->dtnum = hash + 1;
- types[hash] = (char*)malloc( strlen(stddt)+1 );
- if( types[hash]==0 ){
- fprintf(stderr,"Out of memory.\n");
- exit(1);
- }
- strcpy(types[hash],stddt);
- }
- }
-
- /* Print out the definition of YYTOKENTYPE and YYMINORTYPE */
- name = lemp->name ? lemp->name : "Parse";
- lineno = *plineno;
- if( mhflag ){ fprintf(out,"#if INTERFACE\n"); lineno++; }
- fprintf(out,"#define %sTOKENTYPE %s\n",name,
- lemp->tokentype?lemp->tokentype:"void*"); lineno++;
- if( mhflag ){ fprintf(out,"#endif\n"); lineno++; }
- fprintf(out,"typedef union {\n"); lineno++;
- fprintf(out," %sTOKENTYPE yy0;\n",name); lineno++;
- for(i=0; i<arraysize; i++){
- if( types[i]==0 ) continue;
- fprintf(out," %s yy%d;\n",types[i],i+1); lineno++;
- free(types[i]);
- }
- fprintf(out," int yy%d;\n",lemp->errsym->dtnum); lineno++;
- free(stddt);
- free(types);
- fprintf(out,"} YYMINORTYPE;\n"); lineno++;
- *plineno = lineno;
-}
-
-char def_stacksize[] = "100";
-
-/* Generate C source code for the parser */
-void ReportTable(
- struct lemon *lemp,
- int mhflag) /* Output in makeheaders format if true */
-{
- FILE *out, *in;
- char line[LINESIZE];
- int lineno;
- struct state *stp;
- struct action *ap;
- struct rule *rp;
- int i;
- int tablecnt;
- const char *name;
-
- in = tplt_open(lemp);
- if( in==0 ) return;
- out = file_open(lemp,".c","w");
- if( out==0 ){
- fclose(in);
- return;
- }
- lineno = 1;
- tplt_xfer(lemp->name,in,out,&lineno);
-
- /* Generate the include code, if any */
- tplt_print(out,lemp,lemp->include,lemp->includeln,&lineno);
- if( mhflag ){
- char *name2 = file_makename(lemp, ".h");
- fprintf(out,"#include \"%s\"\n", name); lineno++;
- free(name2);
- }
- tplt_xfer(lemp->name,in,out,&lineno);
-
- /* Generate #defines for all tokens */
- if( mhflag ){
- const char *prefix;
- fprintf(out,"#if INTERFACE\n"); lineno++;
- if( lemp->tokenprefix ) prefix = lemp->tokenprefix;
- else prefix = "";
- for(i=1; i<lemp->nterminal; i++){
- fprintf(out,"#define %s%-30s %2d\n",prefix,lemp->symbols[i]->name,i);
- lineno++;
- }
- fprintf(out,"#endif\n"); lineno++;
- }
- tplt_xfer(lemp->name,in,out,&lineno);
-
- /* Generate the defines */
- fprintf(out,"/* \001 */\n");
- fprintf(out,"#define YYCODETYPE %s\n",
- lemp->nsymbol>250?"int":"unsigned char"); lineno++;
- fprintf(out,"#define YYNOCODE %d\n",lemp->nsymbol+1); lineno++;
- fprintf(out,"#define YYACTIONTYPE %s\n",
- lemp->nstate+lemp->nrule>250?"int":"unsigned char"); lineno++;
- print_stack_union(out,lemp,&lineno,mhflag);
- if( lemp->stacksize ){
- if( atoi(lemp->stacksize)<=0 ){
- ErrorMsg(lemp->filename,0,
-"Illegal stack size: [%s]. The stack size should be an integer constant.",
- lemp->stacksize);
- lemp->errorcnt++;
- lemp->stacksize = def_stacksize;
- }
- fprintf(out,"#define YYSTACKDEPTH %s\n",lemp->stacksize); lineno++;
- }else{
- fprintf(out,"#define YYSTACKDEPTH 100\n"); lineno++;
- }
- if( mhflag ){
- fprintf(out,"#if INTERFACE\n"); lineno++;
- }
- name = lemp->name ? lemp->name : "Parse";
- if( lemp->arg && lemp->arg[0] ){
- int j;
- j = strlen(lemp->arg);
- while( j>=1 && safe_isspace(lemp->arg[j-1]) ) j--;
- while( j>=1 && (safe_isalnum(lemp->arg[j-1]) || lemp->arg[j-1]=='_') ) j--;
- fprintf(out,"#define %sARGDECL ,%s\n",name,&lemp->arg[j]); lineno++;
- fprintf(out,"#define %sXARGDECL %s;\n",name,lemp->arg); lineno++;
- fprintf(out,"#define %sANSIARGDECL ,%s\n",name,lemp->arg); lineno++;
- }else{
- fprintf(out,"#define %sARGDECL\n",name); lineno++;
- fprintf(out,"#define %sXARGDECL\n",name); lineno++;
- fprintf(out,"#define %sANSIARGDECL\n",name); lineno++;
- }
- if( mhflag ){
- fprintf(out,"#endif\n"); lineno++;
- }
- fprintf(out,"#define YYNSTATE %d\n",lemp->nstate); lineno++;
- fprintf(out,"#define YYNRULE %d\n",lemp->nrule); lineno++;
- fprintf(out,"#define YYERRORSYMBOL %d\n",lemp->errsym->index); lineno++;
- fprintf(out,"#define YYERRSYMDT yy%d\n",lemp->errsym->dtnum); lineno++;
- tplt_xfer(lemp->name,in,out,&lineno);
-
- /* Generate the action table.
- **
- ** Each entry in the action table is an element of the following
- ** structure:
- ** struct yyActionEntry {
- ** YYCODETYPE lookahead;
- ** YYACTIONTYPE action;
- ** struct yyActionEntry *next;
- ** }
- **
- ** The entries are grouped into hash tables, one hash table for each
- ** parser state. The hash table has a size which is the smallest
- ** power of two needed to hold all entries.
- */
- tablecnt = 0;
-
- /* Loop over parser states */
- for(i=0; i<lemp->nstate; i++){
- size_t tablesize; /* size of the hash table */
- unsigned int j,k; /* Loop counter */
- int collide[2048]; /* The collision chain for the table */
- struct action *table[2048]; /* Build the hash table here */
-
- /* Find the number of actions and initialize the hash table */
- stp = lemp->sorted[i];
- stp->tabstart = tablecnt;
- stp->naction = 0;
- for(ap=stp->ap; ap; ap=ap->next){
- if( ap->sp->index!=lemp->nsymbol && compute_action(lemp,ap)>=0 ){
- stp->naction++;
- }
- }
- tablesize = 1;
- while( tablesize<stp->naction ) tablesize += tablesize;
- assert( tablesize<= sizeof(table)/sizeof(table[0]) );
- for(j=0; j<tablesize; j++){
- table[j] = 0;
- collide[j] = -1;
- }
-
- /* Hash the actions into the hash table */
- stp->tabdfltact = lemp->nstate + lemp->nrule;
- for(ap=stp->ap; ap; ap=ap->next){
- int action = compute_action(lemp,ap);
- int h;
- if( ap->sp->index==lemp->nsymbol ){
- stp->tabdfltact = action;
- }else if( action>=0 ){
- h = ap->sp->index & (tablesize-1);
- ap->collide = table[h];
- table[h] = ap;
- }
- }
-
- /* Resolve collisions */
- for(j=k=0; j<tablesize; j++){
- if( table[j] && table[j]->collide ){
- while( table[k] ) k++;
- table[k] = table[j]->collide;
- collide[j] = k;
- table[j]->collide = 0;
- if( k<j ) j = k-1;
- }
- }
-
- /* Print the hash table */
- fprintf(out,"/* State %d */\n",stp->index); lineno++;
- for(j=0; j<tablesize; j++){
- if( table[j]==0 ){
- fprintf(out,
- " {YYNOCODE,0,0}, /* Unused */\n");
- }else{
- fprintf(out," {%4d,%4d, ",
- table[j]->sp->index,
- compute_action(lemp,table[j]));
- if( collide[j]>=0 ){
- fprintf(out,"&yyActionTable[%4d] }, /* ",
- collide[j] + tablecnt);
- }else{
- fprintf(out,"0 }, /* ");
- }
- PrintAction(table[j],out,22);
- fprintf(out," */\n");
- }
- lineno++;
- }
-
- /* Update the table count */
- tablecnt += tablesize;
- }
- tplt_xfer(lemp->name,in,out,&lineno);
- lemp->tablesize = tablecnt;
-
- /* Generate the state table
- **
- ** Each entry is an element of the following structure:
- ** struct yyStateEntry {
- ** struct yyActionEntry *hashtbl;
- ** int mask;
- ** YYACTIONTYPE actionDefault;
- ** }
- */
- for(i=0; i<lemp->nstate; i++){
- size_t tablesize;
- stp = lemp->sorted[i];
- tablesize = 1;
- while( tablesize<stp->naction ) tablesize += tablesize;
- fprintf(out," { &yyActionTable[%d], %lu, %d},\n",
- stp->tabstart,
- (unsigned long)tablesize - 1,
- stp->tabdfltact); lineno++;
- }
- tplt_xfer(lemp->name,in,out,&lineno);
-
- /* Generate a table containing the symbolic name of every symbol */
- for(i=0; i<lemp->nsymbol; i++){
- sprintf(line,"\"%s\",",lemp->symbols[i]->name);
- fprintf(out," %-15s",line);
- if( (i&3)==3 ){ fprintf(out,"\n"); lineno++; }
- }
- if( (i&3)!=0 ){ fprintf(out,"\n"); lineno++; }
- tplt_xfer(lemp->name,in,out,&lineno);
-
- /* Generate code which executes every time a symbol is popped from
- ** the stack while processing errors or while destroying the parser.
- ** (In other words, generate the %destructor actions) */
- if( lemp->tokendest ){
- for(i=0; i<lemp->nsymbol; i++){
- struct symbol *sp = lemp->symbols[i];
- if( sp==0 || sp->type!=TERMINAL ) continue;
- fprintf(out," case %d:\n",sp->index); lineno++;
- }
- for(i=0; i<lemp->nsymbol && lemp->symbols[i]->type!=TERMINAL; i++);
- if( i<lemp->nsymbol ){
- emit_destructor_code(out,lemp->symbols[i],lemp,&lineno);
- fprintf(out," break;\n"); lineno++;
- }
- }
- for(i=0; i<lemp->nsymbol; i++){
- struct symbol *sp = lemp->symbols[i];
- if( sp==0 || sp->type==TERMINAL || sp->destructor==0 ) continue;
- fprintf(out," case %d:\n",sp->index); lineno++;
- emit_destructor_code(out,lemp->symbols[i],lemp,&lineno);
- fprintf(out," break;\n"); lineno++;
- }
- tplt_xfer(lemp->name,in,out,&lineno);
-
- /* Generate code which executes whenever the parser stack overflows */
- tplt_print(out,lemp,lemp->overflow,lemp->overflowln,&lineno);
- tplt_xfer(lemp->name,in,out,&lineno);
-
- /* Generate the table of rule information
- **
- ** Note: This code depends on the fact that rules are number
- ** sequentually beginning with 0.
- */
- for(rp=lemp->rule; rp; rp=rp->next){
- fprintf(out," { %d, %d },\n",rp->lhs->index,rp->nrhs); lineno++;
- }
- tplt_xfer(lemp->name,in,out,&lineno);
-
- /* Generate code which execution during each REDUCE action */
- for(rp=lemp->rule; rp; rp=rp->next){
- fprintf(out," case %d:\n",rp->index); lineno++;
- fprintf(out," YYTRACE(\"%s ::=",rp->lhs->name);
- for(i=0; i<rp->nrhs; i++) fprintf(out," %s",rp->rhs[i]->name);
- fprintf(out,"\")\n"); lineno++;
- emit_code(out,rp,lemp,&lineno);
- fprintf(out," break;\n"); lineno++;
- }
- tplt_xfer(lemp->name,in,out,&lineno);
-
- /* Generate code which executes if a parse fails */
- tplt_print(out,lemp,lemp->failure,lemp->failureln,&lineno);
- tplt_xfer(lemp->name,in,out,&lineno);
-
- /* Generate code which executes when a syntax error occurs */
- tplt_print(out,lemp,lemp->error,lemp->errorln,&lineno);
- tplt_xfer(lemp->name,in,out,&lineno);
-
- /* Generate code which executes when the parser accepts its input */
- tplt_print(out,lemp,lemp->accept,lemp->acceptln,&lineno);
- tplt_xfer(lemp->name,in,out,&lineno);
-
- /* Append any addition code the user desires */
- tplt_print(out,lemp,lemp->extracode,lemp->extracodeln,&lineno);
-
- fclose(in);
- fclose(out);
- return;
-}
-
-/* Generate a header file for the parser */
-void ReportHeader(struct lemon *lemp)
-{
- FILE *out, *in;
- const char *prefix;
- char line[LINESIZE];
- char pattern[LINESIZE];
- int i;
-
- if( lemp->tokenprefix ) prefix = lemp->tokenprefix;
- else prefix = "";
- in = file_open(lemp,".h","r");
- if( in ){
- for(i=1; i<lemp->nterminal && fgets(line,LINESIZE,in); i++){
- sprintf(pattern,"#define %s%-30s %2d\n",prefix,lemp->symbols[i]->name,i);
- if( strcmp(line,pattern) ) break;
- }
- fclose(in);
- if( i==lemp->nterminal ){
- /* No change in the file. Don't rewrite it. */
- return;
- }
- }
- out = file_open(lemp,".h","w");
- if( out ){
- for(i=1; i<lemp->nterminal; i++){
- fprintf(out,"#define %s%-30s %2d\n",prefix,lemp->symbols[i]->name,i);
- }
- fclose(out);
- }
- return;
-}
-
-/* Reduce the size of the action tables, if possible, by making use
-** of defaults.
-**
-** In this version, if all REDUCE actions use the same rule, make
-** them the default. Only default them if there are more than one.
-*/
-void CompressTables(struct lemon *lemp)
-{
- struct state *stp;
- struct action *ap;
- struct rule *rp;
- int i;
- int cnt;
-
- for(i=0; i<lemp->nstate; i++){
- stp = lemp->sorted[i];
-
- /* Find the first REDUCE action */
- for(ap=stp->ap; ap && ap->type!=REDUCE; ap=ap->next);
- if( ap==0 ) continue;
-
- /* Remember the rule used */
- rp = ap->x.rp;
-
- /* See if all other REDUCE acitons use the same rule */
- cnt = 1;
- for(ap=ap->next; ap; ap=ap->next){
- if( ap->type==REDUCE ){
- if( ap->x.rp!=rp ) break;
- cnt++;
- }
- }
- if( ap || cnt==1 ) continue;
-
- /* Combine all REDUCE actions into a single default */
- for(ap=stp->ap; ap && ap->type!=REDUCE; ap=ap->next);
- assert( ap );
- ap->sp = Symbol_new("{default}");
- for(ap=ap->next; ap; ap=ap->next){
- if( ap->type==REDUCE ) ap->type = NOT_USED;
- }
- stp->ap = Action_sort(stp->ap);
- }
-}
-/***************** From the file "set.c" ************************************/
-/*
-** Set manipulation routines for the LEMON parser generator.
-*/
-
-static int size = 0;
-
-/* Set the set size */
-void SetSize(int n)
-{
- size = n+1;
-}
-
-/* Allocate a new set */
-char *SetNew(void){
- char *s;
- int i;
- s = (char*)malloc( size );
- if( s==0 ){
- memory_error();
- }
- for(i=0; i<size; i++) s[i] = 0;
- return s;
-}
-
-/* Deallocate a set */
-void SetFree(char *s)
-{
- free(s);
-}
-
-/* Add a new element to the set. Return TRUE if the element was added
-** and FALSE if it was already there. */
-int SetAdd(char *s, int e)
-{
- int rv;
- rv = s[e];
- s[e] = 1;
- return !rv;
-}
-
-/* Add every element of s2 to s1. Return TRUE if s1 changes. */
-int SetUnion(char *s1, char *s2)
-{
- int i, progress;
- progress = 0;
- for(i=0; i<size; i++){
- if( s2[i]==0 ) continue;
- if( s1[i]==0 ){
- progress = 1;
- s1[i] = 1;
- }
- }
- return progress;
-}
-/********************** From the file "table.c" ****************************/
-/*
-** All code in this file has been automatically generated
-** from a specification in the file
-** "table.q"
-** by the associative array code building program "aagen".
-** Do not edit this file! Instead, edit the specification
-** file, then rerun aagen.
-*/
-/*
-** Code for processing tables in the LEMON parser generator.
-*/
-PRIVATE int strhash(const char *);
-PRIVATE int statecmp(struct config *, struct config *);
-PRIVATE int statehash(struct config *);
-PRIVATE int confighash(struct config *);
-
-PRIVATE int strhash(const char *x)
-{
- int h = 0;
- while( *x) h = h*13 + *(x++);
- return h;
-}
-
-/* Works like strdup, sort of. Save a string in malloced memory, but
-** keep strings in a table so that the same string is not in more
-** than one place.
-*/
-char *Strsafe(const char *y)
-{
- char *z;
-
- z = Strsafe_find(y);
- if( z==0 && (z=malloc( strlen(y)+1 ))!=0 ){
- strcpy(z,y);
- Strsafe_insert(z);
- }
- MemoryCheck(z);
- return z;
-}
-
-/* There is one instance of the following structure for each
-** associative array of type "x1".
-*/
-struct s_x1 {
- int size; /* The number of available slots. */
- /* Must be a power of 2 greater than or */
- /* equal to 1 */
- int count; /* Number of currently slots filled */
- struct s_x1node *tbl; /* The data stored here */
- struct s_x1node **ht; /* Hash table for lookups */
-};
-
-/* There is one instance of this structure for every data element
-** in an associative array of type "x1".
-*/
-typedef struct s_x1node {
- char *data; /* The data */
- struct s_x1node *next; /* Next entry with the same hash */
- struct s_x1node **from; /* Previous link */
-} x1node;
-
-/* There is only one instance of the array, which is the following */
-static struct s_x1 *x1a;
-
-/* Allocate a new associative array */
-void Strsafe_init(void){
- if( x1a ) return;
- x1a = (struct s_x1*)malloc( sizeof(struct s_x1) );
- if( x1a ){
- x1a->size = 1024;
- x1a->count = 0;
- x1a->tbl = (x1node*)malloc(
- (sizeof(x1node) + sizeof(x1node*))*1024 );
- if( x1a->tbl==0 ){
- free(x1a);
- x1a = 0;
- }else{
- int i;
- x1a->ht = (x1node**)&(x1a->tbl[1024]);
- for(i=0; i<1024; i++) x1a->ht[i] = 0;
- }
- }
-}
-/* Insert a new record into the array. Return TRUE if successful.
-** Prior data with the same key is NOT overwritten */
-int Strsafe_insert(char *data)
-{
- x1node *np;
- int h;
- int ph;
-
- if( x1a==0 ) return 0;
- ph = strhash(data);
- h = ph & (x1a->size-1);
- np = x1a->ht[h];
- while( np ){
- if( strcmp(np->data,data)==0 ){
- /* An existing entry with the same key is found. */
- /* Fail because overwrite is not allows. */
- return 0;
- }
- np = np->next;
- }
- if( x1a->count>=x1a->size ){
- /* Need to make the hash table bigger */
- int i,mysize;
- struct s_x1 array;
- array.size = mysize = x1a->size*2;
- array.count = x1a->count;
- array.tbl = (x1node*)malloc(
- (sizeof(x1node) + sizeof(x1node*))*mysize );
- if( array.tbl==0 ) return 0; /* Fail due to malloc failure */
- array.ht = (x1node**)&(array.tbl[mysize]);
- for(i=0; i<mysize; i++) array.ht[i] = 0;
- for(i=0; i<x1a->count; i++){
- x1node *oldnp, *newnp;
- oldnp = &(x1a->tbl[i]);
- h = strhash(oldnp->data) & (mysize-1);
- newnp = &(array.tbl[i]);
- if( array.ht[h] ) array.ht[h]->from = &(newnp->next);
- newnp->next = array.ht[h];
- newnp->data = oldnp->data;
- newnp->from = &(array.ht[h]);
- array.ht[h] = newnp;
- }
- free(x1a->tbl);
- *x1a = array;
- }
- /* Insert the new data */
- h = ph & (x1a->size-1);
- np = &(x1a->tbl[x1a->count++]);
- np->data = data;
- if( x1a->ht[h] ) x1a->ht[h]->from = &(np->next);
- np->next = x1a->ht[h];
- x1a->ht[h] = np;
- np->from = &(x1a->ht[h]);
- return 1;
-}
-
-/* Return a pointer to data assigned to the given key. Return NULL
-** if no such key. */
-char *Strsafe_find(const char *key)
-{
- int h;
- x1node *np;
-
- if( x1a==0 ) return 0;
- h = strhash(key) & (x1a->size-1);
- np = x1a->ht[h];
- while( np ){
- if( strcmp(np->data,key)==0 ) break;
- np = np->next;
- }
- return np ? np->data : 0;
-}
-
-/* Return a pointer to the (terminal or nonterminal) symbol "x".
-** Create a new symbol if this is the first time "x" has been seen.
-*/
-struct symbol *Symbol_new(const char *x)
-{
- struct symbol *sp;
-
- sp = Symbol_find(x);
- if( sp==0 ){
- sp = (struct symbol *)malloc( sizeof(struct symbol) );
- MemoryCheck(sp);
- sp->name = Strsafe(x);
- sp->type = safe_isupper(*x) ? TERMINAL : NONTERMINAL;
- sp->rule = 0;
- sp->prec = -1;
- sp->assoc = UNK;
- sp->firstset = 0;
- sp->lambda = BOOL_FALSE;
- sp->destructor = 0;
- sp->datatype = 0;
- Symbol_insert(sp,sp->name);
- }
- return sp;
-}
-
-/* Compare two symbols */
-int Symbolcmpp(const void *a_arg, const void *b_arg)
-{
-/* MSVC complains about this, but it's wrong. GCC does not
-complain about this, as is right. From Guy Harris:
-
-At least as I read the ANSI C spec, GCC is right and MSVC is wrong here.
-The arguments are pointers to "const void", and should be cast to
-pointers to "const struct symbol *"; however, at least as I read the
-spec, "const struct symbol **" is "pointer to pointer to const struct
-symbol", not "pointer to const pointer to struct symbol".
-*/
-
- struct symbol *const *a = a_arg;
- struct symbol *const *b = b_arg;
-
- return strcmp((**a).name,(**b).name);
-}
-
-/* There is one instance of the following structure for each
-** associative array of type "x2".
-*/
-struct s_x2 {
- int size; /* The number of available slots. */
- /* Must be a power of 2 greater than or */
- /* equal to 1 */
- int count; /* Number of currently slots filled */
- struct s_x2node *tbl; /* The data stored here */
- struct s_x2node **ht; /* Hash table for lookups */
-};
-
-/* There is one instance of this structure for every data element
-** in an associative array of type "x2".
-*/
-typedef struct s_x2node {
- struct symbol *data; /* The data */
- char *key; /* The key */
- struct s_x2node *next; /* Next entry with the same hash */
- struct s_x2node **from; /* Previous link */
-} x2node;
-
-/* There is only one instance of the array, which is the following */
-static struct s_x2 *x2a;
-
-/* Allocate a new associative array */
-void Symbol_init(void){
- if( x2a ) return;
- x2a = (struct s_x2*)malloc( sizeof(struct s_x2) );
- if( x2a ){
- x2a->size = 128;
- x2a->count = 0;
- x2a->tbl = (x2node*)malloc(
- (sizeof(x2node) + sizeof(x2node*))*128 );
- if( x2a->tbl==0 ){
- free(x2a);
- x2a = 0;
- }else{
- int i;
- x2a->ht = (x2node**)&(x2a->tbl[128]);
- for(i=0; i<128; i++) x2a->ht[i] = 0;
- }
- }
-}
-/* Insert a new record into the array. Return TRUE if successful.
-** Prior data with the same key is NOT overwritten */
-int Symbol_insert(struct symbol *data, char *key)
-{
- x2node *np;
- int h;
- int ph;
-
- if( x2a==0 ) return 0;
- ph = strhash(key);
- h = ph & (x2a->size-1);
- np = x2a->ht[h];
- while( np ){
- if( strcmp(np->key,key)==0 ){
- /* An existing entry with the same key is found. */
- /* Fail because overwrite is not allows. */
- return 0;
- }
- np = np->next;
- }
- if( x2a->count>=x2a->size ){
- /* Need to make the hash table bigger */
- int i,mysize;
- struct s_x2 array;
- array.size = mysize = x2a->size*2;
- array.count = x2a->count;
- array.tbl = (x2node*)malloc(
- (sizeof(x2node) + sizeof(x2node*))*mysize );
- if( array.tbl==0 ) return 0; /* Fail due to malloc failure */
- array.ht = (x2node**)&(array.tbl[mysize]);
- for(i=0; i<mysize; i++) array.ht[i] = 0;
- for(i=0; i<x2a->count; i++){
- x2node *oldnp, *newnp;
- oldnp = &(x2a->tbl[i]);
- h = strhash(oldnp->key) & (mysize-1);
- newnp = &(array.tbl[i]);
- if( array.ht[h] ) array.ht[h]->from = &(newnp->next);
- newnp->next = array.ht[h];
- newnp->key = oldnp->key;
- newnp->data = oldnp->data;
- newnp->from = &(array.ht[h]);
- array.ht[h] = newnp;
- }
- free(x2a->tbl);
- *x2a = array;
- }
- /* Insert the new data */
- h = ph & (x2a->size-1);
- np = &(x2a->tbl[x2a->count++]);
- np->key = key;
- np->data = data;
- if( x2a->ht[h] ) x2a->ht[h]->from = &(np->next);
- np->next = x2a->ht[h];
- x2a->ht[h] = np;
- np->from = &(x2a->ht[h]);
- return 1;
-}
-
-/* Return a pointer to data assigned to the given key. Return NULL
-** if no such key. */
-struct symbol *Symbol_find(const char *key)
-{
- int h;
- x2node *np;
-
- if( x2a==0 ) return 0;
- h = strhash(key) & (x2a->size-1);
- np = x2a->ht[h];
- while( np ){
- if( strcmp(np->key,key)==0 ) break;
- np = np->next;
- }
- return np ? np->data : 0;
-}
-
-/* Return the n-th data. Return NULL if n is out of range. */
-struct symbol *Symbol_Nth(int n)
-{
- struct symbol *data;
- if( x2a && n>0 && n<=x2a->count ){
- data = x2a->tbl[n-1].data;
- }else{
- data = 0;
- }
- return data;
-}
-
-/* Return the size of the array */
-int Symbol_count(void)
-{
- return x2a ? x2a->count : 0;
-}
-
-/* Return an array of pointers to all data in the table.
-** The array is obtained from malloc. Return NULL if memory allocation
-** problems, or if the array is empty. */
-struct symbol **Symbol_arrayof(void)
-{
- struct symbol **array;
- int i,mysize;
- if( x2a==0 ) return 0;
- mysize = x2a->count;
- array = (struct symbol **)malloc( sizeof(struct symbol *)*mysize );
- if( array ){
- for(i=0; i<mysize; i++) array[i] = x2a->tbl[i].data;
- }
- return array;
-}
-
-/* Compare two configurations */
-int Configcmp(const void *a_arg, const void *b_arg)
-{
- const struct config *a = a_arg, *b = b_arg;
- int x;
- x = a->rp->index - b->rp->index;
- if( x==0 ) x = a->dot - b->dot;
- return x;
-}
-
-/* Compare two states */
-PRIVATE int statecmp(struct config *a, struct config *b)
-{
- int rc;
- for(rc=0; rc==0 && a && b; a=a->bp, b=b->bp){
- rc = a->rp->index - b->rp->index;
- if( rc==0 ) rc = a->dot - b->dot;
- }
- if( rc==0 ){
- if( a ) rc = 1;
- if( b ) rc = -1;
- }
- return rc;
-}
-
-/* Hash a state */
-PRIVATE int statehash(struct config *a)
-{
- int h=0;
- while( a ){
- h = h*571 + a->rp->index*37 + a->dot;
- a = a->bp;
- }
- return h;
-}
-
-/* Allocate a new state structure */
-struct state *State_new(void)
-{
- struct state *new;
- new = (struct state *)malloc( sizeof(struct state) );
- MemoryCheck(new);
- return new;
-}
-
-/* There is one instance of the following structure for each
-** associative array of type "x3".
-*/
-struct s_x3 {
- int size; /* The number of available slots. */
- /* Must be a power of 2 greater than or */
- /* equal to 1 */
- int count; /* Number of currently slots filled */
- struct s_x3node *tbl; /* The data stored here */
- struct s_x3node **ht; /* Hash table for lookups */
-};
-
-/* There is one instance of this structure for every data element
-** in an associative array of type "x3".
-*/
-typedef struct s_x3node {
- struct state *data; /* The data */
- struct config *key; /* The key */
- struct s_x3node *next; /* Next entry with the same hash */
- struct s_x3node **from; /* Previous link */
-} x3node;
-
-/* There is only one instance of the array, which is the following */
-static struct s_x3 *x3a;
-
-/* Allocate a new associative array */
-void State_init(void){
- if( x3a ) return;
- x3a = (struct s_x3*)malloc( sizeof(struct s_x3) );
- if( x3a ){
- x3a->size = 128;
- x3a->count = 0;
- x3a->tbl = (x3node*)malloc(
- (sizeof(x3node) + sizeof(x3node*))*128 );
- if( x3a->tbl==0 ){
- free(x3a);
- x3a = 0;
- }else{
- int i;
- x3a->ht = (x3node**)&(x3a->tbl[128]);
- for(i=0; i<128; i++) x3a->ht[i] = 0;
- }
- }
-}
-/* Insert a new record into the array. Return TRUE if successful.
-** Prior data with the same key is NOT overwritten */
-int State_insert(struct state *data, struct config *key)
-{
- x3node *np;
- int h;
- int ph;
-
- if( x3a==0 ) return 0;
- ph = statehash(key);
- h = ph & (x3a->size-1);
- np = x3a->ht[h];
- while( np ){
- if( statecmp(np->key,key)==0 ){
- /* An existing entry with the same key is found. */
- /* Fail because overwrite is not allows. */
- return 0;
- }
- np = np->next;
- }
- if( x3a->count>=x3a->size ){
- /* Need to make the hash table bigger */
- int i,mysize;
- struct s_x3 array;
- array.size = mysize = x3a->size*2;
- array.count = x3a->count;
- array.tbl = (x3node*)malloc(
- (sizeof(x3node) + sizeof(x3node*))*mysize );
- if( array.tbl==0 ) return 0; /* Fail due to malloc failure */
- array.ht = (x3node**)&(array.tbl[mysize]);
- for(i=0; i<mysize; i++) array.ht[i] = 0;
- for(i=0; i<x3a->count; i++){
- x3node *oldnp, *newnp;
- oldnp = &(x3a->tbl[i]);
- h = statehash(oldnp->key) & (mysize-1);
- newnp = &(array.tbl[i]);
- if( array.ht[h] ) array.ht[h]->from = &(newnp->next);
- newnp->next = array.ht[h];
- newnp->key = oldnp->key;
- newnp->data = oldnp->data;
- newnp->from = &(array.ht[h]);
- array.ht[h] = newnp;
- }
- free(x3a->tbl);
- *x3a = array;
- }
- /* Insert the new data */
- h = ph & (x3a->size-1);
- np = &(x3a->tbl[x3a->count++]);
- np->key = key;
- np->data = data;
- if( x3a->ht[h] ) x3a->ht[h]->from = &(np->next);
- np->next = x3a->ht[h];
- x3a->ht[h] = np;
- np->from = &(x3a->ht[h]);
- return 1;
-}
-
-/* Return a pointer to data assigned to the given key. Return NULL
-** if no such key. */
-struct state *State_find(struct config *key)
-{
- int h;
- x3node *np;
-
- if( x3a==0 ) return 0;
- h = statehash(key) & (x3a->size-1);
- np = x3a->ht[h];
- while( np ){
- if( statecmp(np->key,key)==0 ) break;
- np = np->next;
- }
- return np ? np->data : 0;
-}
-
-/* Return an array of pointers to all data in the table.
-** The array is obtained from malloc. Return NULL if memory allocation
-** problems, or if the array is empty. */
-struct state **State_arrayof(void)
-{
- struct state **array;
- int i,mysize;
- if( x3a==0 ) return 0;
- mysize = x3a->count;
- array = (struct state **)malloc( sizeof(struct state *)*mysize );
- if( array ){
- for(i=0; i<mysize; i++) array[i] = x3a->tbl[i].data;
- }
- return array;
-}
-
-/* Hash a configuration */
-PRIVATE int confighash(struct config *a)
-{
- int h=0;
- h = h*571 + a->rp->index*37 + a->dot;
- return h;
-}
-
-/* There is one instance of the following structure for each
-** associative array of type "x4".
-*/
-struct s_x4 {
- int size; /* The number of available slots. */
- /* Must be a power of 2 greater than or */
- /* equal to 1 */
- int count; /* Number of currently slots filled */
- struct s_x4node *tbl; /* The data stored here */
- struct s_x4node **ht; /* Hash table for lookups */
-};
-
-/* There is one instance of this structure for every data element
-** in an associative array of type "x4".
-*/
-typedef struct s_x4node {
- struct config *data; /* The data */
- struct s_x4node *next; /* Next entry with the same hash */
- struct s_x4node **from; /* Previous link */
-} x4node;
-
-/* There is only one instance of the array, which is the following */
-static struct s_x4 *x4a;
-
-/* Allocate a new associative array */
-void Configtable_init(void){
- if( x4a ) return;
- x4a = (struct s_x4*)malloc( sizeof(struct s_x4) );
- if( x4a ){
- x4a->size = 64;
- x4a->count = 0;
- x4a->tbl = (x4node*)malloc(
- (sizeof(x4node) + sizeof(x4node*))*64 );
- if( x4a->tbl==0 ){
- free(x4a);
- x4a = 0;
- }else{
- int i;
- x4a->ht = (x4node**)&(x4a->tbl[64]);
- for(i=0; i<64; i++) x4a->ht[i] = 0;
- }
- }
-}
-/* Insert a new record into the array. Return TRUE if successful.
-** Prior data with the same key is NOT overwritten */
-int Configtable_insert(struct config *data)
-{
- x4node *np;
- int h;
- int ph;
-
- if( x4a==0 ) return 0;
- ph = confighash(data);
- h = ph & (x4a->size-1);
- np = x4a->ht[h];
- while( np ){
- if( Configcmp(np->data,data)==0 ){
- /* An existing entry with the same key is found. */
- /* Fail because overwrite is not allows. */
- return 0;
- }
- np = np->next;
- }
- if( x4a->count>=x4a->size ){
- /* Need to make the hash table bigger */
- int i,mysize;
- struct s_x4 array;
- array.size = mysize = x4a->size*2;
- array.count = x4a->count;
- array.tbl = (x4node*)malloc(
- (sizeof(x4node) + sizeof(x4node*))*mysize );
- if( array.tbl==0 ) return 0; /* Fail due to malloc failure */
- array.ht = (x4node**)&(array.tbl[mysize]);
- for(i=0; i<mysize; i++) array.ht[i] = 0;
- for(i=0; i<x4a->count; i++){
- x4node *oldnp, *newnp;
- oldnp = &(x4a->tbl[i]);
- h = confighash(oldnp->data) & (mysize-1);
- newnp = &(array.tbl[i]);
- if( array.ht[h] ) array.ht[h]->from = &(newnp->next);
- newnp->next = array.ht[h];
- newnp->data = oldnp->data;
- newnp->from = &(array.ht[h]);
- array.ht[h] = newnp;
- }
- free(x4a->tbl);
- *x4a = array;
- }
- /* Insert the new data */
- h = ph & (x4a->size-1);
- np = &(x4a->tbl[x4a->count++]);
- np->data = data;
- if( x4a->ht[h] ) x4a->ht[h]->from = &(np->next);
- np->next = x4a->ht[h];
- x4a->ht[h] = np;
- np->from = &(x4a->ht[h]);
- return 1;
-}
-
-/* Return a pointer to data assigned to the given key. Return NULL
-** if no such key. */
-struct config *Configtable_find(struct config *key)
-{
- int h;
- x4node *np;
-
- if( x4a==0 ) return 0;
- h = confighash(key) & (x4a->size-1);
- np = x4a->ht[h];
- while( np ){
- if( Configcmp(np->data,key)==0 ) break;
- np = np->next;
- }
- return np ? np->data : 0;
-}
-
-/* Remove all data from the table. Pass each data to the function "f"
-** as it is removed. ("f" may be null to avoid this step.) */
-void Configtable_clear(int(*f)(struct config *))
-{
- int i;
- if( x4a==0 || x4a->count==0 ) return;
- if( f ) for(i=0; i<x4a->count; i++) (*f)(x4a->tbl[i].data);
- for(i=0; i<x4a->size; i++) x4a->ht[i] = 0;
- x4a->count = 0;
- return;
-}
+++ /dev/null
-<html>
-<head>
-<title>The Lemon Parser Generator</title>
-</head>
-<body bgcolor=white>
-<h1 align=center>The Lemon Parser Generator</h1>
-
-<p>Lemon is an LALR(1) parser generator for C or C++.
-It does the same job as ``bison'' and ``yacc''.
-But lemon is not another bison or yacc clone. It
-uses a different grammar syntax which is designed to
-reduce the number of coding errors. Lemon also uses a more
-sophisticated parsing engine that is faster than yacc and
-bison and which is both reentrant and thread-safe.
-Furthermore, Lemon implements features that can be used
-to eliminate resource leaks, making is suitable for use
-in long-running programs such as graphical user interfaces
-or embedded controllers.</p>
-
-<p>This document is an introduction to the Lemon
-parser generator.</p>
-
-<h2>Theory of Operation</h2>
-
-<p>The main goal of Lemon is to translate a context free grammar (CFG)
-for a particular language into C code that implements a parser for
-that language.
-The program has two inputs:
-<ul>
-<li>The grammar specification.
-<li>A parser template file.
-</ul>
-Typically, only the grammar specification is supplied by the programmer.
-Lemon comes with a default parser template which works fine for most
-applications. But the user is free to substitute a different parser
-template if desired.</p>
-
-<p>Depending on command-line options, Lemon will generate between
-one and three files of outputs.
-<ul>
-<li>C code to implement the parser.
-<li>A header file defining an integer ID for each terminal symbol.
-<li>An information file that describes the states of the generated parser
- automaton.
-</ul>
-By default, all three of these output files are generated.
-The header file is suppressed if the ``-m'' command-line option is
-used and the report file is omitted when ``-q'' is selected.</p>
-
-<p>The grammar specification file uses a ``.y'' suffix, by convention.
-In the examples used in this document, we'll assume the name of the
-grammar file is ``gram.y''. A typical use of Lemon would be the
-following command:
-<pre>
- lemon gram.y
-</pre>
-This command will generate three output files named ``gram.c'',
-``gram.h'' and ``gram.out''.
-The first is C code to implement the parser. The second
-is the header file that defines numerical values for all
-terminal symbols, and the last is the report that explains
-the states used by the parser automaton.</p>
-
-<h3>Command Line Options</h3>
-
-<p>The behavior of Lemon can be modified using command-line options.
-You can obtain a list of the available command-line options together
-with a brief explanation of what each does by typing
-<pre>
- lemon -?
-</pre>
-As of this writing, the following command-line options are supported:
-<ul>
-<li><tt>-b</tt>
-<li><tt>-c</tt>
-<li><tt>-g</tt>
-<li><tt>-m</tt>
-<li><tt>-q</tt>
-<li><tt>-s</tt>
-<li><tt>-x</tt>
-</ul>
-The ``-b'' option reduces the amount of text in the report file by
-printing only the basis of each parser state, rather than the full
-configuration.
-The ``-c'' option suppresses action table compression. Using -c
-will make the parser a little larger and slower but it will detect
-syntax errors sooner.
-The ``-g'' option causes no output files to be generated at all.
-Instead, the input grammar file is printed on standard output but
-with all comments, actions and other extraneous text deleted. This
-is a useful way to get a quick summary of a grammar.
-The ``-m'' option causes the output C source file to be compatible
-with the ``makeheaders'' program.
-Makeheaders is a program that automatically generates header files
-from C source code. When the ``-m'' option is used, the header
-file is not output since the makeheaders program will take care
-of generated all header files automatically.
-The ``-q'' option suppresses the report file.
-Using ``-s'' causes a brief summary of parser statistics to be
-printed. Like this:
-<pre>
- Parser statistics: 74 terminals, 70 nonterminals, 179 rules
- 340 states, 2026 parser table entries, 0 conflicts
-</pre>
-Finally, the ``-x'' option causes Lemon to print its version number
-and copyright information
-and then stop without attempting to read the grammar or generate a parser.</p>
-
-<h3>The Parser Interface</h3>
-
-<p>Lemon doesn't generate a complete, working program. It only generates
-a few subroutines that implement a parser. This section describes
-the interface to those subroutines. It is up to the programmer to
-call these subroutines in an appropriate way in order to produce a
-complete system.</p>
-
-<p>Before a program begins using a Lemon-generated parser, the program
-must first create the parser.
-A new parser is created as follows:
-<pre>
- void *pParser = ParseAlloc( malloc );
-</pre>
-The ParseAlloc() routine allocates and initializes a new parser and
-returns a pointer to it.
-The actual data structure used to represent a parser is opaque --
-its internal structure is not visible or usable by the calling routine.
-For this reason, the ParseAlloc() routine returns a pointer to void
-rather than a pointer to some particular structure.
-The sole argument to the ParseAlloc() routine is a pointer to the
-subroutine used to allocate memory. Typically this means ``malloc()''.</p>
-
-<p>After a program is finished using a parser, it can reclaim all
-memory allocated by that parser by calling
-<pre>
- ParseFree(pParser, free);
-</pre>
-The first argument is the same pointer returned by ParseAlloc(). The
-second argument is a pointer to the function used to release bulk
-memory back to the system.</p>
-
-<p>After a parser has been allocated using ParseAlloc(), the programmer
-must supply the parser with a sequence of tokens (terminal symbols) to
-be parsed. This is accomplished by calling the following function
-once for each token:
-<pre>
- Parse(pParser, hTokenID, sTokenData, pArg);
-</pre>
-The first argument to the Parse() routine is the pointer returned by
-ParseAlloc().
-The second argument is a small positive integer that tells the parse the
-type of the next token in the data stream.
-There is one token type for each terminal symbol in the grammar.
-The gram.h file generated by Lemon contains #define statements that
-map symbolic terminal symbol names into appropriate integer values.
-(A value of 0 for the second argument is a special flag to the
-parser to indicate that the end of input has been reached.)
-The third argument is the value of the given token. By default,
-the type of the third argument is integer, but the grammar will
-usually redefine this type to be some kind of structure.
-Typically the second argument will be a broad category of tokens
-such as ``identifier'' or ``number'' and the third argument will
-be the name of the identifier or the value of the number.</p>
-
-<p>The Parse() function may have either three or four arguments,
-depending on the grammar. If the grammar specification file request
-it, the Parse() function will have a fourth parameter that can be
-of any type chosen by the programmer. The parser doesn't do anything
-with this argument except to pass it through to action routines.
-This is a convenient mechanism for passing state information down
-to the action routines without having to use global variables.</p>
-
-<p>A typical use of a Lemon parser might look something like the
-following:
-<pre>
- 01 ParseTree *ParseFile(const char *zFilename){
- 02 Tokenizer *pTokenizer;
- 03 void *pParser;
- 04 Token sToken;
- 05 int hTokenId;
- 06 ParserState sState;
- 07
- 08 pTokenizer = TokenizerCreate(zFilename);
- 09 pParser = ParseAlloc( malloc );
- 10 InitParserState(&sState);
- 11 while( GetNextToken(pTokenizer, &hTokenId, &sToken) ){
- 12 Parse(pParser, hTokenId, sToken, &sState);
- 13 }
- 14 Parse(pParser, 0, sToken, &sState);
- 15 ParseFree(pParser, free );
- 16 TokenizerFree(pTokenizer);
- 17 return sState.treeRoot;
- 18 }
-</pre>
-This example shows a user-written routine that parses a file of
-text and returns a pointer to the parse tree.
-(We've omitted all error-handling from this example to keep it
-simple.)
-We assume the existence of some kind of tokenizer which is created
-using TokenizerCreate() on line 8 and deleted by TokenizerFree()
-on line 16. The GetNextToken() function on line 11 retrieves the
-next token from the input file and puts its type in the
-integer variable hTokenId. The sToken variable is assumed to be
-some kind of structure that contains details about each token,
-such as its complete text, what line it occurs on, etc. </p>
-
-<p>This example also assumes the existence of structure of type
-ParserState that holds state information about a particular parse.
-An instance of such a structure is created on line 6 and initialized
-on line 10. A pointer to this structure is passed into the Parse()
-routine as the optional 4th argument.
-The action routine specified by the grammar for the parser can use
-the ParserState structure to hold whatever information is useful and
-appropriate. In the example, we note that the treeRoot field of
-the ParserState structure is left pointing to the root of the parse
-tree.</p>
-
-<p>The core of this example as it relates to Lemon is as follows:
-<pre>
- ParseFile(){
- pParser = ParseAlloc( malloc );
- while( GetNextToken(pTokenizer,&hTokenId, &sToken) ){
- Parse(pParser, hTokenId, sToken);
- }
- Parse(pParser, 0, sToken);
- ParseFree(pParser, free );
- }
-</pre>
-Basically, what a program has to do to use a Lemon-generated parser
-is first create the parser, then send it lots of tokens obtained by
-tokenizing an input source. When the end of input is reached, the
-Parse() routine should be called one last time with a token type
-of 0. This step is necessary to inform the parser that the end of
-input has been reached. Finally, we reclaim memory used by the
-parser by calling ParseFree().</p>
-
-<p>There is one other interface routine that should be mentioned
-before we move on.
-The ParseTrace() function can be used to generate debugging output
-from the parser. A prototype for this routine is as follows:
-<pre>
- ParseTrace(FILE *stream, char *zPrefix);
-</pre>
-After this routine is called, a short (one-line) message is written
-to the designated output stream every time the parser changes states
-or calls an action routine. Each such message is prefaced using
-the text given by zPrefix. This debugging output can be turned off
-by calling ParseTrace() again with a first argument of NULL (0).</p>
-
-<h3>Differences With YACC and BISON</h3>
-
-<p>Programmers who have previously used the yacc or bison parser
-generator will notice several important differences between yacc and/or
-bison and Lemon.
-<ul>
-<li>In yacc and bison, the parser calls the tokenizer. In Lemon,
- the tokenizer calls the parser.
-<li>Lemon uses no global variables. Yacc and bison use global variables
- to pass information between the tokenizer and parser.
-<li>Lemon allows multiple parsers to be running simultaneously. Yacc
- and bison do not.
-</ul>
-These differences may cause some initial confusion for programmers
-with prior yacc and bison experience.
-But after years of experience using Lemon, I firmly
-believe that the Lemon way of doing things is better.</p>
-
-<h2>Input File Syntax</h2>
-
-<p>The main purpose of the grammar specification file for Lemon is
-to define the grammar for the parser. But the input file also
-specifies additional information Lemon requires to do its job.
-Most of the work in using Lemon is in writing an appropriate
-grammar file.</p>
-
-<p>The grammar file for lemon is, for the most part, free format.
-It does not have sections or divisions like yacc or bison. Any
-declaration can occur at any point in the file.
-Lemon ignores whitespace (except where it is needed to separate
-tokens) and it honors the same commenting conventions as C and C++.</p>
-
-<h3>Terminals and Nonterminals</h3>
-
-<p>A terminal symbol (token) is any string of alphanumeric
-and underscore characters
-that begins with an upper case letter.
-A terminal can contain lower class letters after the first character,
-but the usual convention is to make terminals all upper case.
-A nonterminal, on the other hand, is any string of alphanumeric
-and underscore characters than begins with a lower case letter.
-Again, the usual convention is to make nonterminals use all lower
-case letters.</p>
-
-<p>In Lemon, terminal and nonterminal symbols do not need to
-be declared or identified in a separate section of the grammar file.
-Lemon is able to generate a list of all terminals and nonterminals
-by examining the grammar rules, and it can always distinguish a
-terminal from a nonterminal by checking the case of the first
-character of the name.</p>
-
-<p>Yacc and bison allow terminal symbols to have either alphanumeric
-names or to be individual characters included in single quotes, like
-this: ')' or '$'. Lemon does not allow this alternative form for
-terminal symbols. With Lemon, all symbols, terminals and nonterminals,
-must have alphanumeric names.</p>
-
-<h3>Grammar Rules</h3>
-
-<p>The main component of a Lemon grammar file is a sequence of grammar
-rules.
-Each grammar rule consists of a nonterminal symbol followed by
-the special symbol ``::='' and then a list of terminals and/or nonterminals.
-The rule is terminated by a period.
-The list of terminals and nonterminals on the right-hand side of the
-rule can be empty.
-Rules can occur in any order, except that the left-hand side of the
-first rule is assumed to be the start symbol for the grammar (unless
-specified otherwise using the <tt>%start</tt> directive described below.)
-A typical sequence of grammar rules might look something like this:
-<pre>
- expr ::= expr PLUS expr.
- expr ::= expr TIMES expr.
- expr ::= LPAREN expr RPAREN.
- expr ::= VALUE.
-</pre>
-</p>
-
-<p>There is one non-terminal in this example, ``expr'', and five
-terminal symbols or tokens: ``PLUS'', ``TIMES'', ``LPAREN'',
-``RPAREN'' and ``VALUE''.</p>
-
-<p>Like yacc and bison, Lemon allows the grammar to specify a block
-of C code that will be executed whenever a grammar rule is reduced
-by the parser.
-In Lemon, this action is specified by putting the C code (contained
-within curly braces <tt>{...}</tt>) immediately after the
-period that closes the rule.
-For example:
-<pre>
- expr ::= expr PLUS expr. { printf("Doing an addition...\n"); }
-</pre>
-</p>
-
-<p>In order to be useful, grammar actions must normally be linked to
-their associated grammar rules.
-In yacc and bison, this is accomplished by embedding a ``$$'' in the
-action to stand for the value of the left-hand side of the rule and
-symbols ``$1'', ``$2'', and so forth to stand for the value of
-the terminal or nonterminal at position 1, 2 and so forth on the
-right-hand side of the rule.
-This idea is very powerful, but it is also very error-prone. The
-single most common source of errors in a yacc or bison grammar is
-to miscount the number of symbols on the right-hand side of a grammar
-rule and say ``$7'' when you really mean ``$8''.</p>
-
-<p>Lemon avoids the need to count grammar symbols by assigning symbolic
-names to each symbol in a grammar rule and then using those symbolic
-names in the action.
-In yacc or bison, one would write this:
-<pre>
- expr -> expr PLUS expr { $$ = $1 + $3; };
-</pre>
-But in Lemon, the same rule becomes the following:
-<pre>
- expr(A) ::= expr(B) PLUS expr(C). { A = B+C; }
-</pre>
-In the Lemon rule, any symbol in parentheses after a grammar rule
-symbol becomes a place holder for that symbol in the grammar rule.
-This place holder can then be used in the associated C action to
-stand for the value of that symbol.<p>
-
-<p>The Lemon notation for linking a grammar rule with its reduce
-action is superior to yacc/bison on several counts.
-First, as mentioned above, the Lemon method avoids the need to
-count grammar symbols.
-Secondly, if a terminal or nonterminal in a Lemon grammar rule
-includes a linking symbol in parentheses but that linking symbol
-is not actually used in the reduce action, then an error message
-is generated.
-For example, the rule
-<pre>
- expr(A) ::= expr(B) PLUS expr(C). { A = B; }
-</pre>
-will generate an error because the linking symbol ``C'' is used
-in the grammar rule but not in the reduce action.</p>
-
-<p>The Lemon notation for linking grammar rules to reduce actions
-also facilitates the use of destructors for reclaiming memory
-allocated by the values of terminals and nonterminals on the
-right-hand side of a rule.</p>
-
-<h3>Precedence Rules</h3>
-
-<p>Lemon resolves parsing ambiguities in exactly the same way as
-yacc and bison. A shift-reduce conflict is resolved in favor
-of the shift, and a reduce-reduce conflict is resolved by reducing
-whichever rule comes first in the grammar file.</p>
-
-<p>Just like in
-yacc and bison, Lemon allows a measure of control
-over the resolution of paring conflicts using precedence rules.
-A precedence value can be assigned to any terminal symbol
-using the %left, %right or %nonassoc directives. Terminal symbols
-mentioned in earlier directives have a lower precedence that
-terminal symbols mentioned in later directives. For example:</p>
-
-<p><pre>
- %left AND.
- %left OR.
- %nonassoc EQ NE GT GE LT LE.
- %left PLUS MINUS.
- %left TIMES DIVIDE MOD.
- %right EXP NOT.
-</pre></p>
-
-<p>In the preceding sequence of directives, the AND operator is
-defined to have the lowest precedence. The OR operator is one
-precedence level higher. And so forth. Hence, the grammar would
-attempt to group the ambiguous expression
-<pre>
- a AND b OR c
-</pre>
-like this
-<pre>
- a AND (b OR c).
-</pre>
-The associativity (left, right or nonassoc) is used to determine
-the grouping when the precedence is the same. AND is left-associative
-in our example, so
-<pre>
- a AND b AND c
-</pre>
-is parsed like this
-<pre>
- (a AND b) AND c.
-</pre>
-The EXP operator is right-associative, though, so
-<pre>
- a EXP b EXP c
-</pre>
-is parsed like this
-<pre>
- a EXP (b EXP c).
-</pre>
-The nonassoc precedence is used for non-associative operators.
-So
-<pre>
- a EQ b EQ c
-</pre>
-is an error.</p>
-
-<p>The precedence of non-terminals is transferred to rules as follows:
-The precedence of a grammar rule is equal to the precedence of the
-left-most terminal symbol in the rule for which a precedence is
-defined. This is normally what you want, but in those cases where
-you want to precedence of a grammar rule to be something different,
-you can specify an alternative precedence symbol by putting the
-symbol in square braces after the period at the end of the rule and
-before any C-code. For example:</p>
-
-<p><pre>
- expr = MINUS expr. [NOT]
-</pre></p>
-
-<p>This rule has a precedence equal to that of the NOT symbol, not the
-MINUS symbol as would have been the case by default.</p>
-
-<p>With the knowledge of how precedence is assigned to terminal
-symbols and individual
-grammar rules, we can now explain precisely how parsing conflicts
-are resolved in Lemon. Shift-reduce conflicts are resolved
-as follows:
-<ul>
-<li> If either the token to be shifted or the rule to be reduced
- lacks precedence information, then resolve in favor of the
- shift, but report a parsing conflict.
-<li> If the precedence of the token to be shifted is greater than
- the precedence of the rule to reduce, then resolve in favor
- of the shift. No parsing conflict is reported.
-<li> If the precedence of the token it be shifted is less than the
- precedence of the rule to reduce, then resolve in favor of the
- reduce action. No parsing conflict is reported.
-<li> If the precedences are the same and the shift token is
- right-associative, then resolve in favor of the shift.
- No parsing conflict is reported.
-<li> If the precedences are the same the the shift token is
- left-associative, then resolve in favor of the reduce.
- No parsing conflict is reported.
-<li> Otherwise, resolve the conflict by doing the shift and
- report the parsing conflict.
-</ul>
-Reduce-reduce conflicts are resolved this way:
-<ul>
-<li> If either reduce rule
- lacks precedence information, then resolve in favor of the
- rule that appears first in the grammar and report a parsing
- conflict.
-<li> If both rules have precedence and the precedence is different
- then resolve the dispute in favor of the rule with the highest
- precedence and do not report a conflict.
-<li> Otherwise, resolve the conflict by reducing by the rule that
- appears first in the grammar and report a parsing conflict.
-</ul>
-
-<h3>Special Directives</h3>
-
-<p>The input grammar to Lemon consists of grammar rules and special
-directives. We've described all the grammar rules, so now we'll
-talk about the special directives.</p>
-
-<p>Directives in lemon can occur in any order. You can put them before
-the grammar rules, or after the grammar rules, or in the mist of the
-grammar rules. It doesn't matter. The relative order of
-directives used to assign precedence to terminals is important, but
-other than that, the order of directives in Lemon is arbitrary.</p>
-
-<p>Lemon supports the following special directives:
-<ul>
-<li><tt>%destructor</tt>
-<li><tt>%extra_argument</tt>
-<li><tt>%include</tt>
-<li><tt>%left</tt>
-<li><tt>%name</tt>
-<li><tt>%nonassoc</tt>
-<li><tt>%parse_accept</tt>
-<li><tt>%parse_failure </tt>
-<li><tt>%right</tt>
-<li><tt>%stack_overflow</tt>
-<li><tt>%stack_size</tt>
-<li><tt>%start_symbol</tt>
-<li><tt>%syntax_error</tt>
-<li><tt>%token_destructor</tt>
-<li><tt>%token_prefix</tt>
-<li><tt>%token_type</tt>
-<li><tt>%type</tt>
-</ul>
-Each of these directives will be described separately in the
-following sections:</p>
-
-<h4>The <tt>%destructor</tt> directive</h4>
-
-<p>The %destructor directive is used to specify a destructor for
-a non-terminal symbol.
-(See also the %token_destructor directive which is used to
-specify a destructor for terminal symbols.)</p>
-
-<p>A non-terminal's destructor is called to dispose of the
-non-terminal's value whenever the non-terminal is popped from
-the stack. This includes all of the following circumstances:
-<ul>
-<li> When a rule reduces and the value of a non-terminal on
- the right-hand side is not linked to C code.
-<li> When the stack is popped during error processing.
-<li> When the ParseFree() function runs.
-</ul>
-The destructor can do whatever it wants with the value of
-the non-terminal, but its design is to deallocate memory
-or other resources held by that non-terminal.</p>
-
-<p>Consider an example:
-<pre>
- %type nt {void*}
- %destructor nt { free($$); }
- nt(A) ::= ID NUM. { A = malloc( 100 ); }
-</pre>
-This example is a bit contrived but it serves to illustrate how
-destructors work. The example shows a non-terminal named
-``nt'' that holds values of type ``void*''. When the rule for
-an ``nt'' reduces, it sets the value of the non-terminal to
-space obtained from malloc(). Later, when the nt non-terminal
-is popped from the stack, the destructor will fire and call
-free() on this malloced space, thus avoiding a memory leak.
-(Note that the symbol ``$$'' in the destructor code is replaced
-by the value of the non-terminal.)</p>
-
-<p>It is important to note that the value of a non-terminal is passed
-to the destructor whenever the non-terminal is removed from the
-stack, unless the non-terminal is used in a C-code action. If
-the non-terminal is used by C-code, then it is assumed that the
-C-code will take care of destroying it if it should really
-be destroyed. More commonly, the value is used to build some
-larger structure and we don't want to destroy it, which is why
-the destructor is not called in this circumstance.</p>
-
-<p>By appropriate use of destructors, it is possible to
-build a parser using Lemon that can be used within a long-running
-program, such as a GUI, that will not leak memory or other resources.
-To do the same using yacc or bison is much more difficult.</p>
-
-<h4>The <tt>%extra_argument</tt> directive</h4>
-
-The %extra_argument directive instructs Lemon to add a 4th parameter
-to the parameter list of the Parse() function it generates. Lemon
-doesn't do anything itself with this extra argument, but it does
-make the argument available to C-code action routines, destructors,
-and so forth. For example, if the grammar file contains:</p>
-
-<p><pre>
- %extra_argument { MyStruct *pAbc }
-</pre></p>
-
-<p>Then the Parse() function generated will have an 4th parameter
-of type ``MyStruct*'' and all action routines will have access to
-a variable named ``pAbc'' that is the value of the 4th parameter
-in the most recent call to Parse().</p>
-
-<h4>The <tt>%include</tt> directive</h4>
-
-<p>The %include directive specifies C code that is included at the
-top of the generated parser. You can include any text you want --
-the Lemon parser generator copies to blindly. If you have multiple
-%include directives in your grammar file, their values are concatenated
-before being put at the beginning of the generated parser.</p>
-
-<p>The %include directive is very handy for getting some extra #include
-preprocessor statements at the beginning of the generated parser.
-For example:</p>
-
-<p><pre>
- %include {#include <unistd.h>}
-</pre></p>
-
-<p>This might be needed, for example, if some of the C actions in the
-grammar call functions that are prototyed in unistd.h.</p>
-
-<h4>The <tt>%left</tt> directive</h4>
-
-The %left directive is used (along with the %right and
-%nonassoc directives) to declare precedences of terminal
-symbols. Every terminal symbol whose name appears after
-a %left directive but before the next period (``.'') is
-given the same left-associative precedence value. Subsequent
-%left directives have higher precedence. For example:</p>
-
-<p><pre>
- %left AND.
- %left OR.
- %nonassoc EQ NE GT GE LT LE.
- %left PLUS MINUS.
- %left TIMES DIVIDE MOD.
- %right EXP NOT.
-</pre></p>
-
-<p>Note the period that terminates each %left, %right or %nonassoc
-directive.</p>
-
-<p>LALR(1) grammars can get into a situation where they require
-a large amount of stack space if you make heavy use or right-associative
-operators. For this reason, it is recommended that you use %left
-rather than %right whenever possible.</p>
-
-<h4>The <tt>%name</tt> directive</h4>
-
-<p>By default, the functions generated by Lemon all begin with the
-five-character string ``Parse''. You can change this string to something
-different using the %name directive. For instance:</p>
-
-<p><pre>
- %name Abcde
-</pre></p>
-
-<p>Putting this directive in the grammar file will cause Lemon to generate
-functions named
-<ul>
-<li> AbcdeAlloc(),
-<li> AbcdeFree(),
-<li> AbcdeTrace(), and
-<li> Abcde().
-</ul>
-The %name directive allows you to generator two or more different
-parsers and link them all into the same executable.
-</p>
-
-<h4>The <tt>%nonassoc</tt> directive</h4>
-
-<p>This directive is used to assign non-associative precedence to
-one or more terminal symbols. See the section on precedence rules
-or on the %left directive for additional information.</p>
-
-<h4>The <tt>%parse_accept</tt> directive</h4>
-
-<p>The %parse_accept directive specifies a block of C code that is
-executed whenever the parser accepts its input string. To ``accept''
-an input string means that the parser was able to process all tokens
-without error.</p>
-
-<p>For example:</p>
-
-<p><pre>
- %parse_accept {
- printf("parsing complete!\n");
- }
-</pre></p>
-
-
-<h4>The <tt>%parse_failure</tt> directive</h4>
-
-<p>The %parse_failure directive specifies a block of C code that
-is executed whenever the parser fails complete. This code is not
-executed until the parser has tried and failed to resolve an input
-error using is usual error recovery strategy. The routine is
-only invoked when parsing is unable to continue.</p>
-
-<p><pre>
- %parse_failure {
- fprintf(stderr,"Giving up. Parser is hopelessly lost...\n");
- }
-</pre></p>
-
-<h4>The <tt>%right</tt> directive</h4>
-
-<p>This directive is used to assign right-associative precedence to
-one or more terminal symbols. See the section on precedence rules
-or on the %left directive for additional information.</p>
-
-<h4>The <tt>%stack_overflow</tt> directive</h4>
-
-<p>The %stack_overflow directive specifies a block of C code that
-is executed if the parser's internal stack ever overflows. Typically
-this just prints an error message. After a stack overflow, the parser
-will be unable to continue and must be reset.</p>
-
-<p><pre>
- %stack_overflow {
- fprintf(stderr,"Giving up. Parser stack overflow\n");
- }
-</pre></p>
-
-<p>You can help prevent parser stack overflows by avoiding the use
-of right recursion and right-precedence operators in your grammar.
-Use left recursion and and left-precedence operators instead, to
-encourage rules to reduce sooner and keep the stack size down.
-For example, do rules like this:
-<pre>
- list ::= list element. // left-recursion. Good!
- list ::= .
-</pre>
-Not like this:
-<pre>
- list ::= element list. // right-recursion. Bad!
- list ::= .
-</pre>
-
-<h4>The <tt>%stack_size</tt> directive</h4>
-
-<p>If stack overflow is a problem and you can't resolve the trouble
-by using left-recursion, then you might want to increase the size
-of the parser's stack using this directive. Put an positive integer
-after the %stack_size directive and Lemon will generate a parse
-with a stack of the requested size. The default value is 100.</p>
-
-<p><pre>
- %stack_size 2000
-</pre></p>
-
-<h4>The <tt>%start_symbol</tt> directive</h4>
-
-<p>By default, the start-symbol for the grammar that Lemon generates
-is the first non-terminal that appears in the grammar file. But you
-can choose a different start-symbol using the %start_symbol directive.</p>
-
-<p><pre>
- %start_symbol prog
-</pre></p>
-
-<h4>The <tt>%token_destructor</tt> directive</h4>
-
-<p>The %destructor directive assigns a destructor to a non-terminal
-symbol. (See the description of the %destructor directive above.)
-This directive does the same thing for all terminal symbols.</p>
-
-<p>Unlike non-terminal symbols which may each have a different data type
-for their values, terminals all use the same data type (defined by
-the %token_type directive) and so they use a common destructor. Other
-than that, the token destructor works just like the non-terminal
-destructors.</p>
-
-<h4>The <tt>%token_prefix</tt> directive</h4>
-
-<p>Lemon generates #defines that assign small integer constants
-to each terminal symbol in the grammar. If desired, Lemon will
-add a prefix specified by this directive
-to each of the #defines it generates.
-So if the default output of Lemon looked like this:
-<pre>
- #define AND 1
- #define MINUS 2
- #define OR 3
- #define PLUS 4
-</pre>
-You can insert a statement into the grammar like this:
-<pre>
- %token_prefix TOKEN_
-</pre>
-to cause Lemon to produce these symbols instead:
-<pre>
- #define TOKEN_AND 1
- #define TOKEN_MINUS 2
- #define TOKEN_OR 3
- #define TOKEN_PLUS 4
-</pre>
-
-<h4>The <tt>%token_type</tt> and <tt>%type</tt> directives</h4>
-
-<p>These directives are used to specify the data types for values
-on the parser's stack associated with terminal and non-terminal
-symbols. The values of all terminal symbols must be of the same
-type. This turns out to be the same data type as the 3rd parameter
-to the Parse() function generated by Lemon. Typically, you will
-make the value of a terminal symbol by a pointer to some kind of
-token structure. Like this:</p>
-
-<p><pre>
- %token_type {Token*}
-</pre></p>
-
-<p>If the data type of terminals is not specified, the default value
-is ``int''.</p>
-
-<p>Non-terminal symbols can each have their own data types. Typically
-the data type of a non-terminal is a pointer to the root of a parse-tree
-structure that contains all information about that non-terminal.
-For example:</p>
-
-<p><pre>
- %type expr {Expr*}
-</pre></p>
-
-<p>Each entry on the parser's stack is actually a union containing
-instances of all data types for every non-terminal and terminal symbol.
-Lemon will automatically use the correct element of this union depending
-on what the corresponding non-terminal or terminal symbol is. But
-the grammar designer should keep in mind that the size of the union
-will be the size of its largest element. So if you have a single
-non-terminal whose data type requires 1K of storage, then your 100
-entry parser stack will require 100K of heap space. If you are willing
-and able to pay that price, fine. You just need to know.</p>
-
-<h3>Error Processing</h3>
-
-<p>After extensive experimentation over several years, it has been
-discovered that the error recovery strategy used by yacc is about
-as good as it gets. And so that is what Lemon uses.</p>
-
-<p>When a Lemon-generated parser encounters a syntax error, it
-first invokes the code specified by the %syntax_error directive, if
-any. It then enters its error recovery strategy. The error recovery
-strategy is to begin popping the parsers stack until it enters a
-state where it is permitted to shift a special non-terminal symbol
-named ``error''. It then shifts this non-terminal and continues
-parsing. But the %syntax_error routine will not be called again
-until at least three new tokens have been successfully shifted.</p>
-
-<p>If the parser pops its stack until the stack is empty, and it still
-is unable to shift the error symbol, then the %parse_failed routine
-is invoked and the parser resets itself to its start state, ready
-to begin parsing a new file. This is what will happen at the very
-first syntax error, of course, if there are no instances of the
-``error'' non-terminal in your grammar.</p>
-
-</body>
-</html>
projects / yasm / commitdiff