From: Vern Paxson <vern@ee.lbl.gov>
Date: Wed, 14 Mar 1990 13:39:41 +0000 (+0000)
Subject:  Tweaks for NUL chars.
X-Git-Tag: flex-2-5-5b~555
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=99ed9836390f8fc31923e0d2e2208e462a2a4d06;p=flex

 Tweaks for NUL chars.
---

diff --git a/ecs.c b/ecs.c
index d5ac84b..c7ca3bb 100644
--- a/ecs.c
+++ b/ecs.c
@@ -80,15 +80,18 @@ ccl2ecl()
  *
  * synopsis
  *    int cre8ecs();
- *    number of classes = cre8ecs( fwd, bck, num );
+ *    number of classes = cre8ecs( fwd, bck, num, start_pos );
  *
  *  fwd is the forward linked-list of equivalence class members.  bck
  *  is the backward linked-list, and num is the number of class members.
+ *  start_pos is 0 if the class members begin in fwd[] and bck[] at
+ *  position 0, and 1 if they begin at position 1.
+ *
  *  Returned is the number of classes.
  */
 
-int cre8ecs( fwd, bck, num )
-int fwd[], bck[], num;
+int cre8ecs( fwd, bck, num, start_pos )
+int fwd[], bck[], num, start_pos;
 
     {
     int i, j, numcl;
@@ -101,7 +104,7 @@ int fwd[], bck[], num;
      * class.
      */
 
-    for ( i = 1; i <= num; ++i )
+    for ( i = start_pos; i < num + start_pos; ++i )
 	if ( bck[i] == NIL )
 	    {
 	    bck[i] = ++numcl;
@@ -129,7 +132,7 @@ int ecmap[];
     {
     int i;
 
-    for ( i = 1; i <= csize; ++i )
+    for ( i = (uses_NUL ? 0 : 1); i < csize; ++i )
 	if ( xlation[i] == 0 )
 	    ecmap[i] = num_xlations + 1;
 	else
diff --git a/flexdef.h b/flexdef.h
index 1a154cb..793f785 100644
--- a/flexdef.h
+++ b/flexdef.h
@@ -31,7 +31,7 @@
 #endif
 
 #ifdef FLEX_8_BIT_CHARS
-#define CSIZE 255
+#define CSIZE 256
 #define Char unsigned char
 #else
 #define Char char
@@ -167,7 +167,7 @@ char *sprintf(); /* keep lint happy */
 
 /* size of input alphabet - should be size of ASCII set */
 #ifndef CSIZE
-#define CSIZE 127
+#define CSIZE 128
 #endif
 
 #define INITIAL_MAX_CCLS 100	/* max number of unique character classes */
@@ -332,7 +332,7 @@ extern struct hash_entry *ccltab[CCL_HASH_SIZE];
  * backtrack_report - if true (i.e., -b flag), generate "lex.backtrack" file
  *   listing backtracking states
  * csize - size of character set for the scanner we're generating;
- *   127 for 7-bit chars and 255 for 8-bit
+ *   128 for 7-bit chars and 256 for 8-bit
  * yymore_used - if true, yymore() is used in input rules
  * reject - if true, generate backtracking tables for REJECT macro
  * real_reject - if true, scanner really uses REJECT (as opposed to just
@@ -470,8 +470,15 @@ extern int protcomst[MSP], firstprot, lastprot, protsave[PROT_SAVE_SIZE];
  * num_xlations - number of different xlation values
  */
 
-extern int numecs, nextecm[CSIZE + 1], ecgroup[CSIZE + 1], nummecs;
+extern int numecs, nextecm[CSIZE], ecgroup[CSIZE], nummecs;
+
+/* meta-equivalence classes are indexed starting at 1, so it's possible
+ * that they will require positions from 1 .. CSIZE, i.e., CSIZE + 1
+ * slots total (since the arrays are 0-based).  nextecm[] and ecgroup[]
+ * don't require the extra position since they're indexed from 1 .. CSIZE - 1.
+ */
 extern int tecfwd[CSIZE + 1], tecbck[CSIZE + 1];
+
 extern int *xlation;
 extern int num_xlations;
 
@@ -569,12 +576,13 @@ extern Char *ccltbl;
  * hshsave - number of hash collisions saved by checking number of states
  * num_backtracking - number of DFA states requiring back-tracking
  * bol_needed - whether scanner needs beginning-of-line recognition
+ * uses_NUL - true if the scanner needs to be able to recognize NUL's
  */
 
 extern char *starttime, *endtime, nmstr[MAXLINE];
 extern int sectnum, nummt, hshcol, dfaeql, numeps, eps2, num_reallocs;
 extern int tmpuses, totnst, peakpairs, numuniq, numdup, hshsave;
-extern int num_backtracking, bol_needed;
+extern int num_backtracking, bol_needed, uses_NUL;
 
 char *allocate_array(), *reallocate_array();