-Changes between beta-test release of Feb. '88 and initial release:
-
- - many files renamed to remove "flex" prefix
- - input() routine added to compressed and fast skeletons
- - unput() routine added to compressed skeleton
- - -d, -ce support for fast scanners
- - symbol table extended to avoid ugly casts of ints <-> char *'s;
- this may relieve MS-DOS woes
- - actions are now separated with YY_BREAK instead of simple "break"'s
- - fixed bug causing core-dumps if skeleton file could not be opened
- - fixed bugs in logic deciding which options cannot be intermixed
- - initial start condition can now be referred to as <INITIAL>
- - fixed bug which would incorrectly computer trailing context
- count for a pattern like "(foo){3}"; now this is considered
- "variable length", even though it isn't.
- - block comments allowed between rules
- - misc. typos corrected
+Changes between beta-test release of June '88 and previous release:
+
+ User-visible:
+
+ - -p flag generates a performance report to stderr. The report
+ consists of comments regarding features of the scanner rules
+ which result in slower scanners.
+
+ - -b flag generates backtracking information to lex.backtrack.
+ This is a list of scanner states which require backtracking
+ and the characters on which they do so. By adding rules
+ one can remove backtracking states. If all backtracking states
+ are eliminated, the generated scanner will run faster.
+ Backtracking is not yet documented in the manual entry.
+
+ - Variable trailing context now works, i.e., one can have
+ rules like "(foo)*/[ \t]*bletch". Some trailing context
+ patterns still cannot be properly matched and generate
+ error messages. These are patterns where the ending of the
+ first part of the rule matches the beginning of the second
+ part, such as "zx*/xy*", where the 'x*' matches the 'x' at
+ the beginning of the trailing context. Lex won't get these
+ patterns right either.
+
+ - Faster scanners.
+
+ - End-of-file rules. The special rule "<<EOF>>" indicates
+ actions which are to be taken when an end-of-file is
+ encountered and yywrap() returns non-zero (i.e., indicates
+ no further files to process). See manual entry for example.
+
+ - The -r (reject used) flag is gone. flex now scans the input
+ for occurrences of the string "REJECT" to determine if the
+ action is needed. It tries to be intelligent about this but
+ can be fooled. One can force the presence or absence of
+ REJECT by adding a line in the first section of the form
+ "%used REJECT" or "%unused REJECT".
+
+ - yymore() has been implemented. Similarly to REJECT, flex
+ detects the use of yymore(), which can be overridden using
+ "%used" or "%unused".
+
+ - Patterns like "x{0,3}" now work (i.e., with lower-limit == 0).
+
+ - Removed '\^x' for ctrl-x misfeature.
+
+ - Added '\a' and '\v' escape sequences.
+
+ - \<digits> now works for octal escape sequences; previously
+ \0<digits> was required.
+
+ - Better error reporting; line numbers are associated with rules.
+
+ - yyleng is a macro; it cannot be accessed outside of the
+ scanner source file.
+
+ - yytext and yyleng should not be modified within a flex action.
+
+ - Generated scanners #define the name FLEX_SCANNER.
+
+ - Rules are internally separated by YY_BREAK in lex.yy.c rather
+ than break, to allow redefinition.
+
+ - The macro YY_USER_ACTION can be redefined to provide an action
+ which is always executed prior to the matched rule's action.
+
+ - yyrestart() is a new action which can be used to restart
+ the scanner after it has seen an end-of-file (a "real" one,
+ that is, one for which yywrap() returned non-zero). It takes
+ a FILE* argument indicating a new file to scan and sets
+ things up so that a subsequent call to yylex() will start
+ scanning that file.
+
+ - Internal scanner names all preceded by "yy_"
+
+ - lex.yy.c is deleted if errors are encountered during processing.
+
+ - Comments may be put in the first section of the input by preceding
+ them with '#'.
+
+
+
+ Other changes:
+
+ - Some portability-related bugs fixed, in particular for machines
+ with unsigned characters or sizeof( int* ) != sizeof( int ).
+ Also, tweaks for VMS and Microsoft C (MS-DOS), and identifiers all
+ trimmed to be 31 or fewer characters. Shortened file names
+ for dinosaur OS's. Checks for allocating > 64K memory
+ on 16 bit'ers. Amiga tweaks. Compiles using gcc on a Sun-3.
+
+ - Compressed and fast scanner skeletons merged.
+
+ - Skeleton header files done away with.
+
+ - Generated scanner uses prototypes and "const" for __STDC__.
+
+ - -DSV flag is now -DSYS_V for System V compilation.
+
+ - Removed all references to FTL language.
+
+ - Software now covered by BSD Copyright.
+
+ - flex will replace lex in subsequent BSD releases.
#include "flexdef.h"
+static char flex_version[] = "2.0.1 (beta)";
+
/* these globals are all defined and commented in flexdef.h */
int printstats, syntaxerror, eofseen, ddebug, trace, spprdflt;
int interactive, caseins, useecs, fulltbl, usemecs;
int fullspd, gen_line_dirs, performance_report, backtrack_report;
-int yymore_used, reject, real_reject;
+int yymore_used, reject, real_reject, continued_action;
int yymore_really_used, reject_really_used;
int datapos, dataline, linenum;
FILE *skelfile = NULL;
int protcomst[MSP], firstprot, lastprot, protsave[PROT_SAVE_SIZE];
int numecs, nextecm[CSIZE + 1], ecgroup[CSIZE + 1], nummecs, tecfwd[CSIZE + 1];
int tecbck[CSIZE + 1];
-int lastsc, current_max_scs, *scset, *scbol, *scxclu, *actvsc;
+int lastsc, current_max_scs, *scset, *scbol, *scxclu, *sceof, *actvsc;
+char **scname;
int current_max_dfa_size, current_max_xpairs;
int current_max_template_xpairs, current_max_dfas;
int lastdfa, *nxt, *chk, *tnxt;
char action_file_name[] = "flexXXXXXX.tmp";
#endif
+#ifndef SHORT_FILE_NAMES
+static char outfile[] = "lex.yy.c";
+#else
+static char outfile[] = "lexyy.c";
+#endif
+static int outfile_created = 0;
+
/* flex - main program
*
readin();
- if ( ! syntaxerror )
- {
- if ( yymore_really_used == REALLY_USED )
- yymore_used = true;
- else if ( yymore_really_used == REALLY_NOT_USED )
- yymore_used = false;
+ if ( syntaxerror )
+ flexend( 1 );
- if ( reject_really_used == REALLY_USED )
- reject = true;
- else if ( reject_really_used == REALLY_NOT_USED )
- reject = false;
+ if ( yymore_really_used == REALLY_USED )
+ yymore_used = true;
+ else if ( yymore_really_used == REALLY_NOT_USED )
+ yymore_used = false;
- if ( performance_report )
- {
- if ( yymore_used )
- fprintf( stderr,
- "yymore() entails a minor performance penalty\n" );
+ if ( reject_really_used == REALLY_USED )
+ reject = true;
+ else if ( reject_really_used == REALLY_NOT_USED )
+ reject = false;
- if ( reject )
- fprintf( stderr,
- "REJECT entails a large performance penalty\n" );
+ if ( performance_report )
+ {
+ if ( yymore_used )
+ fprintf( stderr,
+ "yymore() entails a minor performance penalty\n" );
- if ( variable_trailing_context_rules )
- fprintf( stderr,
- "Variable trailing context rules entail a large performance penalty\n" );
- }
+ if ( interactive )
+ fprintf( stderr,
+ "-I (interactive) entails a minor performance penalty\n" );
if ( reject )
- real_reject = true;
+ fprintf( stderr,
+ "REJECT entails a large performance penalty\n" );
if ( variable_trailing_context_rules )
- reject = true;
+ fprintf( stderr,
+"Variable trailing context rules entail a large performance penalty\n" );
+ }
- if ( (fulltbl || fullspd) && reject )
- {
- if ( real_reject )
- flexerror( "REJECT cannot be used with -f or -F" );
- else
- flexerror(
- "variable trailing context rules cannot be used with -f or -F" );
- }
+ if ( reject )
+ real_reject = true;
- /* convert the ndfa to a dfa */
- ntod();
+ if ( variable_trailing_context_rules )
+ reject = true;
- /* generate the C state transition tables from the DFA */
- make_tables();
+ if ( (fulltbl || fullspd) && reject )
+ {
+ if ( real_reject )
+ flexerror( "REJECT cannot be used with -f or -F" );
+ else
+ flexerror(
+ "variable trailing context rules cannot be used with -f or -F" );
}
+ /* convert the ndfa to a dfa */
+ ntod();
+
+ /* generate the C state transition tables from the DFA */
+ make_tables();
+
/* note, flexend does not return. It exits with its argument as status. */
flexend( 0 );
{
int tblsiz;
- char *gettime();
+ char *flex_gettime();
if ( skelfile != NULL )
(void) fclose( skelfile );
(void) unlink( action_file_name );
}
+ if ( status != 0 && outfile_created )
+ {
+ (void) fclose( stdout );
+ (void) unlink( outfile );
+ }
+
if ( backtrack_report )
{
if ( num_backtracking == 0 )
if ( printstats )
{
- endtime = gettime();
+ endtime = flex_gettime();
- fprintf( stderr, "flex usage statistics:\n" );
+ fprintf( stderr, "flex version %s usage statistics:\n", flex_version );
fprintf( stderr, " started at %s, finished at %s\n",
starttime, endtime );
{
tblsiz = 2 * (lastdfa + numtemps) + 2 * tblend;
- fprintf( stderr, " %d/%d base/def entries created\n",
+ fprintf( stderr, " %d/%d base-def entries created\n",
lastdfa + numtemps, current_max_dfas );
- fprintf( stderr, " %d/%d (peak %d) nxt/chk entries created\n",
+ fprintf( stderr, " %d/%d (peak %d) nxt-chk entries created\n",
tblend, current_max_xpairs, peakpairs );
fprintf( stderr,
- " %d/%d (peak %d) template nxt/chk entries created\n",
+ " %d/%d (peak %d) template nxt-chk entries created\n",
numtemps * nummecs, current_max_template_xpairs,
numtemps * numecs );
fprintf( stderr, " %d empty table entries\n", nummt );
{
int i, sawcmpflag, use_stdout;
- char *arg, *skelname = NULL, *gettime(), clower(), *mktemp();
+ char *arg, *skelname = NULL, *flex_gettime(), clower(), *mktemp();
printstats = syntaxerror = trace = spprdflt = interactive = caseins = false;
backtrack_report = performance_report = ddebug = fulltbl = fullspd = false;
- yymore_used = reject = false;
+ yymore_used = continued_action = reject = false;
yymore_really_used = reject_really_used = false;
gen_line_dirs = usemecs = useecs = true;
if ( ! use_stdout )
{
-#ifndef SHORT_FILE_NAMES
- FILE *prev_stdout = freopen( "lex.yy.c", "w", stdout );
-#else
- FILE *prev_stdout = freopen( "lexyy.c", "w", stdout );
-#endif
+ FILE *prev_stdout = freopen( outfile, "w", stdout );
if ( prev_stdout == NULL )
flexerror( "could not create lex.yy.c" );
+
+ outfile_created = 1;
}
if ( argc )
lastsc = 0;
/* initialize the statistics */
- starttime = gettime();
+ starttime = flex_gettime();
if ( (skelfile = fopen( skelname, "r" )) == NULL )
lerrsf( "can't open skeleton file %s", skelname );
scset = allocate_integer_array( current_max_scs );
scbol = allocate_integer_array( current_max_scs );
scxclu = allocate_integer_array( current_max_scs );
+ sceof = allocate_integer_array( current_max_scs );
+ scname = allocate_char_ptr_array( current_max_scs );
actvsc = allocate_integer_array( current_max_scs );
current_maxccls = INITIAL_MAX_CCLS;
projects / flex / commitdiff