off-by-one in fbm_compile() (spotted by John Bley

<jbley@cs.cmu.edu>); whitespace adjustments

p4raw-id: //depot/perl@4253

diff --git a/util.c b/util.c
index a92c4db..97401ab 100644 (file)
--- a/util.c
+++ b/util.c
@@ -912,7 +912,7 @@ Perl_mem_collxfrm(pTHX_ const char *s, STRLEN len, STRLEN *xlen)
    If FBMcf_TAIL, the table is created as if the string has a trailing \n. */
 
 void
-Perl_fbm_compile(pTHX_ SV *sv, U32 flags /* not used yet */)
+Perl_fbm_compile(pTHX_ SV *sv, U32 flags)
 {
     register U8 *s;
     register U8 *table;
@@ -928,23 +928,23 @@ Perl_fbm_compile(pTHX_ SV *sv, U32 flags /* not used yet */)
     if (len == 0)              /* TAIL might be on on a zero-length string. */
        return;
     if (len > 2) {
-       I32 mlen = len;
+       U8 mlen;
        unsigned char *sb;
 
-       if (mlen > 255)
+       if (len > 255)
            mlen = 255;
-       Sv_Grow(sv,len + 256 + FBM_TABLE_OFFSET);
+       else
+           mlen = (U8)len;
+       Sv_Grow(sv, len + 256 + FBM_TABLE_OFFSET);
        table = (unsigned char*)(SvPVX(sv) + len + FBM_TABLE_OFFSET);
-       s = table - 1 - FBM_TABLE_OFFSET; /* Last char */
-       for (i = 0; i < 256; i++) {
-           table[i] = mlen;
-       }
-       table[-1] = flags;              /* Not used yet */
+       s = table - 1 - FBM_TABLE_OFFSET;       /* last char */
+       memset((void*)table, mlen, 256);
+       table[-1] = (U8)flags;
        i = 0;
-       sb = s - mlen;
+       sb = s - mlen + 1;                      /* first char (maybe) */
        while (s >= sb) {
            if (table[*s] == mlen)
-               table[*s] = i;
+               table[*s] = (U8)i;
            s--, i++;
        }
     }
@@ -963,7 +963,8 @@ Perl_fbm_compile(pTHX_ SV *sv, U32 flags /* not used yet */)
     BmUSEFUL(sv) = 100;                        /* Initial value */
     if (flags & FBMcf_TAIL)
        SvTAIL_on(sv);
-    DEBUG_r(PerlIO_printf(Perl_debug_log, "rarest char %c at %d\n",BmRARE(sv),BmPREVIOUS(sv)));
+    DEBUG_r(PerlIO_printf(Perl_debug_log, "rarest char %c at %d\n",
+                         BmRARE(sv),BmPREVIOUS(sv)));
 }
 
 /* If SvTAIL(littlestr), it has a fake '\n' at end. */
@@ -1075,15 +1076,17 @@ Perl_fbm_instr(pTHX_ unsigned char *big, register unsigned char *bigend, SV *lit
     }
     if (SvTAIL(littlestr) && !multiline) {     /* tail anchored? */
        s = bigend - littlelen;
-       if (s >= big
-           && bigend[-1] == '\n' 
-           && *s == *little 
+       if (s >= big && bigend[-1] == '\n' && *s == *little 
            /* Automatically of length > 2 */
            && memEQ((char*)s + 1, (char*)little + 1, littlelen - 2))
+       {
            return (char*)s;            /* how sweet it is */
-       if (s[1] == *little && memEQ((char*)s + 2,(char*)little + 1,
-                                    littlelen - 2))
+       }
+       if (s[1] == *little
+           && memEQ((char*)s + 2, (char*)little + 1, littlelen - 2))
+       {
            return (char*)s + 1;        /* how sweet it is */
+       }
        return Nullch;
     }
     if (SvTYPE(littlestr) != SVt_PVBM || !SvVALID(littlestr)) {
@@ -1093,9 +1096,11 @@ Perl_fbm_instr(pTHX_ unsigned char *big, register unsigned char *bigend, SV *lit
        if (!b && SvTAIL(littlestr)) {  /* Automatically multiline!  */
            /* Chop \n from littlestr: */
            s = bigend - littlelen + 1;
-           if (*s == *little && memEQ((char*)s + 1, (char*)little + 1,
-                                      littlelen - 2))
+           if (*s == *little
+               && memEQ((char*)s + 1, (char*)little + 1, littlelen - 2))
+           {
                return (char*)s;
+           }
            return Nullch;
        }
        return b;
@@ -1117,7 +1122,7 @@ Perl_fbm_instr(pTHX_ unsigned char *big, register unsigned char *bigend, SV *lit
 
          top2:
            /*SUPPRESS 560*/
-           if (tmp = table[*s]) {
+           if ((tmp = table[*s])) {
 #ifdef POINTERRIGOR
                if (bigend - s > tmp) {
                    s += tmp;