Re: bash -c exit and linux hints
[p5sagit/p5-mst-13.2.git] / regexec.c
index 8f5278c..a71f1d8 100644 (file)
--- a/regexec.c
+++ b/regexec.c
@@ -221,6 +221,22 @@ typedef struct re_cc_state
 
 #define regcpblow(cp) LEAVE_SCOPE(cp)
 
+#define TRYPAREN(paren, n, input) {                            \
+    if (paren) {                                               \
+       if (n) {                                                \
+           PL_regstartp[paren] = HOPc(input, -1) - PL_bostr;   \
+           PL_regendp[paren] = input - PL_bostr;               \
+       }                                                       \
+       else                                                    \
+           PL_regendp[paren] = -1;                             \
+    }                                                          \
+    if (regmatch(next))                                                \
+       sayYES;                                                 \
+    if (paren && n)                                            \
+       PL_regendp[paren] = -1;                                 \
+}
+
+
 /*
  * pregexec and friends
  */
@@ -309,6 +325,7 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
     register I32 end_shift;
     register char *s;
     register SV *check;
+    char *strbeg;
     char *t;
     I32 ml_anch;
     char *tmp;
@@ -335,23 +352,25 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
        DEBUG_r(PerlIO_printf(Perl_debug_log, "String too short...\n"));
        goto fail;
     }
+    strbeg = (sv && SvPOK(sv)) ? strend - SvCUR(sv) : strpos;
     check = prog->check_substr;
     if (prog->reganch & ROPT_ANCH) {   /* Match at beg-of-str or after \n */
        ml_anch = !( (prog->reganch & ROPT_ANCH_SINGLE)
                     || ( (prog->reganch & ROPT_ANCH_BOL)
                          && !PL_multiline ) ); /* Check after \n? */
 
-       if ((prog->check_offset_min == prog->check_offset_max) && !ml_anch) {
+       if (!ml_anch) {
+         if ( !(prog->reganch & ROPT_ANCH_GPOS) /* Checked by the caller */
+              /* SvCUR is not set on references: SvRV and SvPVX overlap */
+              && sv && !SvROK(sv)
+              && (strpos != strbeg)) {
+             DEBUG_r(PerlIO_printf(Perl_debug_log, "Not at start...\n"));
+             goto fail;
+         }
+         if (prog->check_offset_min == prog->check_offset_max) {
            /* Substring at constant offset from beg-of-str... */
            I32 slen;
 
-           if ( !(prog->reganch & ROPT_ANCH_GPOS) /* Checked by the caller */
-                /* SvCUR is not set on references: SvRV and SvPVX overlap */
-                && sv && !SvROK(sv)
-                && (strpos + SvCUR(sv) != strend)) {
-               DEBUG_r(PerlIO_printf(Perl_debug_log, "Not at start...\n"));
-               goto fail;
-           }
            PL_regeol = strend;                 /* Used in HOP() */
            s = HOPc(strpos, prog->check_offset_min);
            if (SvTAIL(check)) {
@@ -377,6 +396,7 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                         && memNE(SvPVX(check), s, slen)))
                goto report_neq;
            goto success_at_start;
+         }
        }
        /* Match is anchored, but substr is not anchored wrt beg-of-str. */
        s = strpos;
@@ -410,7 +430,6 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
     /* Find a possible match in the region s..strend by looking for
        the "check" substring in the region corrected by start/end_shift. */
     if (flags & REXEC_SCREAM) {
-       char *strbeg = SvPVX(sv);       /* XXXX Assume PV_force() on SCREAM! */
        I32 p = -1;                     /* Internal iterator of scream. */
        I32 *pp = data ? data->scream_pos : &p;
 
@@ -599,9 +618,10 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
          find_anchor:
            while (t < strend - prog->minlen) {
                if (*t == '\n') {
-                   if (t < s - prog->check_offset_min) {
+                   if (t < check_at - prog->check_offset_min) {
                        if (prog->anchored_substr) {
-                           /* We definitely contradict the found anchored
+                           /* Since we moved from the found position,
+                              we definitely contradict the found anchored
                               substr.  Due to the above check we do not
                               contradict "check" substr.
                               Thus we can arrive here only if check substr
@@ -612,14 +632,19 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                                PL_colors[0],PL_colors[1], (long)(strpos - i_strpos), (long)(strpos - i_strpos + prog->anchored_offset)));
                            goto do_other_anchored;
                        }
+                       /* We don't contradict the found floating substring. */
+                       /* XXXX Why not check for STCLASS? */
                        s = t + 1;
                        DEBUG_r(PerlIO_printf(Perl_debug_log, "Found /%s^%s/m at offset %ld...\n",
                            PL_colors[0],PL_colors[1], (long)(s - i_strpos)));
                        goto set_useful;
                    }
-                   DEBUG_r(PerlIO_printf(Perl_debug_log, "Found /%s^%s/m, restarting at offset %ld...\n",
+                   /* Position contradicts check-string */
+                   /* XXXX probably better to look for check-string
+                      than for "\n", so one should lower the limit for t? */
+                   DEBUG_r(PerlIO_printf(Perl_debug_log, "Found /%s^%s/m, restarting lookup for check-string at offset %ld...\n",
                        PL_colors[0],PL_colors[1], (long)(t + 1 - i_strpos)));
-                   strpos = s = t + 1;
+                   other_last = strpos = s = t + 1;
                    goto restart;
                }
                t++;
@@ -628,20 +653,25 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                        PL_colors[0],PL_colors[1]));
            goto fail_finish;
        }
+       else {
+           DEBUG_r(PerlIO_printf(Perl_debug_log, "Starting position does not contradict /%s^%s/m...\n",
+                       PL_colors[0],PL_colors[1]));
+       }
        s = t;
       set_useful:
        ++BmUSEFUL(prog->check_substr); /* hooray/5 */
     }
     else {
        PL_bostr = tmp;
-       /* The found string does not prohibit matching at beg-of-str
+       /* The found string does not prohibit matching at strpos,
           - no optimization of calling REx engine can be performed,
-          unless it was an MBOL and we are not after MBOL. */
+          unless it was an MBOL and we are not after MBOL,
+          or a future STCLASS check will fail this. */
       try_at_start:
        /* Even in this situation we may use MBOL flag if strpos is offset
           wrt the start of the string. */
        if (ml_anch && sv && !SvROK(sv) /* See prev comment on SvROK */
-           && (strpos + SvCUR(sv) != strend) && strpos[-1] != '\n'
+           && (strpos != strbeg) && strpos[-1] != '\n'
            /* May be due to an implicit anchor of m{.*foo}  */
            && !(prog->reganch & ROPT_IMPLICIT))
        {
@@ -649,8 +679,8 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
            goto find_anchor;
        }
        DEBUG_r( if (ml_anch)
-           PerlIO_printf(Perl_debug_log, "Does not contradict /%s^%s/m...\n",
-                       PL_colors[0],PL_colors[1]);
+           PerlIO_printf(Perl_debug_log, "Position at offset %ld does not contradict /%s^%s/m...\n",
+                       (long)(strpos - i_strpos), PL_colors[0],PL_colors[1]);
        );
       success_at_start:
        if (!(prog->reganch & ROPT_NAUGHTY)     /* XXXX If strpos moved? */
@@ -659,9 +689,11 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
            && prog->check_substr == prog->float_substr)
        {
            /* If flags & SOMETHING - do not do it many times on the same match */
+           DEBUG_r(PerlIO_printf(Perl_debug_log, "... Disabling check substring...\n"));
            SvREFCNT_dec(prog->check_substr);
            prog->check_substr = Nullsv;        /* disable */
            prog->float_substr = Nullsv;        /* clear */
+           check = Nullsv;                     /* abort */
            s = strpos;
            /* XXXX This is a remnant of the old implementation.  It
                    looks wasteful, since now INTUIT can use many
@@ -690,7 +722,7 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                ? s + (prog->minlen? cl_l : 0)
                : (prog->float_substr ? check_at - start_shift + cl_l
                                      : strend) ;
-       char *startpos = sv && SvPOK(sv) ? strend - SvCUR(sv) : s;
+       char *startpos = strbeg;
 
        t = s;
        if (prog->reganch & ROPT_UTF8) {        
@@ -724,8 +756,10 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                                               "Could not match STCLASS...\n") );
                        goto fail;
                    }
+                   if (!check)
+                       goto giveup;
                    DEBUG_r( PerlIO_printf(Perl_debug_log,
-                               "Trying %s substr starting at offset %ld...\n",
+                               "Looking for %s substr starting at offset %ld...\n",
                                 what, (long)(s + start_shift - i_strpos)) );
                    goto restart;
                }
@@ -734,8 +768,10 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                    goto retry_floating_check;
                /* Recheck anchored substring, but not floating... */
                s = check_at; 
+               if (!check)
+                   goto giveup;
                DEBUG_r( PerlIO_printf(Perl_debug_log,
-                         "Trying anchored substr starting at offset %ld...\n",
+                         "Looking for anchored substr starting at offset %ld...\n",
                          (long)(other_last - i_strpos)) );
                goto do_other_anchored;
            }
@@ -743,9 +779,11 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                current position only: */
            if (ml_anch) {
                s = t = t + 1;
+               if (!check)
+                   goto giveup;
                DEBUG_r( PerlIO_printf(Perl_debug_log,
-                         "Trying /^/m starting at offset %ld...\n",
-                         (long)(t - i_strpos)) );
+                         "Looking for /%s^%s/m starting at offset %ld...\n",
+                         PL_colors[0],PL_colors[1], (long)(t - i_strpos)) );
                goto try_at_offset;
            }
            if (!prog->float_substr)    /* Could have been deleted */
@@ -764,8 +802,10 @@ Perl_re_intuit_start(pTHX_ regexp *prog, SV *sv, char *strpos,
                     PerlIO_printf(Perl_debug_log, 
                        "Does not contradict STCLASS...\n") );
     }
-    DEBUG_r(PerlIO_printf(Perl_debug_log, "%sGuessed:%s match at offset %ld\n",
-                         PL_colors[4], PL_colors[5], (long)(s - i_strpos)) );
+  giveup:
+    DEBUG_r(PerlIO_printf(Perl_debug_log, "%s%s:%s match at offset %ld\n",
+                         PL_colors[4], (check ? "Guessed" : "Giving up"),
+                         PL_colors[5], (long)(s - i_strpos)) );
     return s;
 
   fail_finish:                         /* Substring not found */
@@ -877,7 +917,9 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, char *strend, char *sta
            PL_reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case BOUNDUTF8:
-           tmp = (I32)(s != startpos) ? utf8_to_uv(reghop((U8*)s, -1), 0) : '\n';
+           tmp = (I32)(s != startpos) ? utf8_to_uv(reghop((U8*)s, -1),
+                                                       strend - s,
+                                                       0, 0) : '\n';
            tmp = ((OP(c) == BOUNDUTF8 ? isALNUM_uni(tmp) : isALNUM_LC_uni(tmp)) != 0);
            while (s < strend) {
                if (tmp == !(OP(c) == BOUNDUTF8 ?
@@ -913,7 +955,9 @@ S_find_byclass(pTHX_ regexp * prog, regnode *c, char *s, char *strend, char *sta
            PL_reg_flags |= RF_tainted;
            /* FALL THROUGH */
        case NBOUNDUTF8:
-           tmp = (I32)(s != startpos) ? utf8_to_uv(reghop((U8*)s, -1), 0) : '\n';
+           tmp = (I32)(s != startpos) ? utf8_to_uv(reghop((U8*)s, -1),
+                                                       strend - s,
+                                                       0, 0) : '\n';
            tmp = ((OP(c) == NBOUNDUTF8 ? isALNUM_uni(tmp) : isALNUM_LC_uni(tmp)) != 0);
            while (s < strend) {
                if (tmp == !(OP(c) == NBOUNDUTF8 ?
@@ -1434,9 +1478,14 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
        /* we have /x+whatever/ */
        /* it must be a one character string (XXXX Except UTF?) */
        char ch = SvPVX(prog->anchored_substr)[0];
+#ifdef DEBUGGING
+       int did_match = 0;
+#endif
+
        if (UTF) {
            while (s < strend) {
                if (*s == ch) {
+                   DEBUG_r( did_match = 1 );
                    if (regtry(prog, s)) goto got_it;
                    s += UTF8SKIP(s);
                    while (s < strend && *s == ch)
@@ -1448,6 +1497,7 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
        else {
            while (s < strend) {
                if (*s == ch) {
+                   DEBUG_r( did_match = 1 );
                    if (regtry(prog, s)) goto got_it;
                    s++;
                    while (s < strend && *s == ch)
@@ -1456,6 +1506,9 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
                s++;
            }
        }
+       DEBUG_r(did_match ||
+               PerlIO_printf(Perl_debug_log,
+                             "Did not find anchored character...\n"));
     }
     /*SUPPRESS 560*/
     else if (prog->anchored_substr != Nullsv
@@ -1471,6 +1524,9 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
                          -(I32)(CHR_SVLEN(must)
                                 - (SvTAIL(must) != 0) + back_min));
        char *last1;            /* Last position checked before */
+#ifdef DEBUGGING
+       int did_match = 0;
+#endif
 
        if (s > PL_bostr)
            last1 = HOPc(s, -1);
@@ -1489,6 +1545,7 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
                 : (s = fbm_instr((unsigned char*)HOP(s, back_min),
                                  (unsigned char*)strend, must, 
                                  PL_multiline ? FBMrf_MULTILINE : 0))) ) {
+           DEBUG_r( did_match = 1 );
            if (HOPc(s, -back_max) > last1) {
                last1 = HOPc(s, -back_min);
                s = HOPc(s, -back_max);
@@ -1514,6 +1571,14 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
                }
            }
        }
+       DEBUG_r(did_match ||
+               PerlIO_printf(Perl_debug_log, "Did not find %s substr `%s%.*s%s'%s...\n",
+                             ((must == prog->anchored_substr)
+                              ? "anchored" : "floating"),
+                             PL_colors[0],
+                             (int)(SvCUR(must) - (SvTAIL(must)!=0)),
+                             SvPVX(must),
+                             PL_colors[1], (SvTAIL(must) ? "$" : "")));
        goto phooey;
     }
     else if ((c = prog->regstclass)) {
@@ -1522,6 +1587,7 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
            strend = HOPc(strend, -(minlen - 1));
        if (find_byclass(prog, c, s, strend, startpos, 0))
            goto got_it;
+       DEBUG_r(PerlIO_printf(Perl_debug_log, "Contradicts stclass...\n"));
     }
     else {
        dontbother = 0;
@@ -1554,7 +1620,12 @@ Perl_regexec_flags(pTHX_ register regexp *prog, char *stringarg, register char *
                        last = strend;  /* matching `$' */
                }
            }
-           if (last == NULL) goto phooey; /* Should not happen! */
+           if (last == NULL) {
+               DEBUG_r(PerlIO_printf(Perl_debug_log,
+                                     "%sCan't trim the tail, match fails (should not happen)%s\n",
+                                     PL_colors[4],PL_colors[5]));
+               goto phooey; /* Should not happen! */
+           }
            dontbother = strend - last + prog->float_min_offset;
        }
        if (minlen && (dontbother < minlen))
@@ -1616,6 +1687,8 @@ got_it:
     return 1;
 
 phooey:
+    DEBUG_r(PerlIO_printf(Perl_debug_log, "%sMatch failed%s\n",
+                         PL_colors[4],PL_colors[5]));
     if (PL_reg_eval_set)
        restore_pos(aTHXo_ 0);
     return 0;
@@ -1840,7 +1913,7 @@ S_regmatch(pTHX_ regnode *prog)
            }
            sayNO;
        case SBOL:
-           if (locinput == PL_regbol && PL_regprev == '\n')
+           if (locinput == PL_bostr)
                break;
            sayNO;
        case GPOS:
@@ -1929,7 +2002,7 @@ S_regmatch(pTHX_ regnode *prog)
                while (s < e) {
                    if (l >= PL_regeol)
                        sayNO;
-                   if (utf8_to_uv((U8*)s, 0) != (c1 ?
+                   if (utf8_to_uv((U8*)s, e - s, 0, 0) != (c1 ?
                                                  toLOWER_utf8((U8*)l) :
                                                  toLOWER_LC_utf8((U8*)l)))
                    {
@@ -2067,7 +2140,8 @@ S_regmatch(pTHX_ regnode *prog)
        case NBOUNDUTF8:
            /* was last char in word? */
            ln = (locinput != PL_regbol)
-               ? utf8_to_uv(reghop((U8*)locinput, -1), 0) : PL_regprev;
+               ? utf8_to_uv(reghop((U8*)locinput, -1),
+                                PL_regeol - locinput, 0, 0) : PL_regprev;
            if (OP(scan) == BOUNDUTF8 || OP(scan) == NBOUNDUTF8) {
                ln = isALNUM_uni(ln);
                n = swash_fetch(PL_utf8_alnum, (U8*)locinput);
@@ -2994,16 +3068,7 @@ S_regmatch(pTHX_ regnode *prog)
                                sayNO;
                        }
                        /* PL_reginput == locinput now */
-                       if (paren) {
-                           if (ln) {
-                               PL_regstartp[paren] = HOPc(locinput, -1) - PL_bostr;
-                               PL_regendp[paren] = locinput - PL_bostr;
-                           }
-                           else
-                               PL_regendp[paren] = -1;
-                       }
-                       if (regmatch(next))
-                           sayYES;
+                       TRYPAREN(paren, ln, locinput);
                        PL_reginput = locinput; /* Could be reset... */
                        REGCP_UNWIND;
                        /* Couldn't or didn't -- move forward. */
@@ -3017,16 +3082,7 @@ S_regmatch(pTHX_ regnode *prog)
                        UCHARAT(PL_reginput) == c1 ||
                        UCHARAT(PL_reginput) == c2)
                    {
-                       if (paren) {
-                           if (n) {
-                               PL_regstartp[paren] = HOPc(PL_reginput, -1) - PL_bostr;
-                               PL_regendp[paren] = PL_reginput - PL_bostr;
-                           }
-                           else
-                               PL_regendp[paren] = -1;
-                       }
-                       if (regmatch(next))
-                           sayYES;
+                       TRYPAREN(paren, n, PL_reginput);
                        REGCP_UNWIND;
                    }
                    /* Couldn't or didn't -- move forward. */
@@ -3060,16 +3116,7 @@ S_regmatch(pTHX_ regnode *prog)
                            UCHARAT(PL_reginput) == c1 ||
                            UCHARAT(PL_reginput) == c2)
                            {
-                               if (paren && n) {
-                                   if (n) {
-                                       PL_regstartp[paren] = HOPc(PL_reginput, -1) - PL_bostr;
-                                       PL_regendp[paren] = PL_reginput - PL_bostr;
-                                   }
-                                   else
-                                       PL_regendp[paren] = -1;
-                               }
-                               if (regmatch(next))
-                                   sayYES;
+                               TRYPAREN(paren, n, PL_reginput);
                                REGCP_UNWIND;
                            }
                        /* Couldn't or didn't -- back up. */
@@ -3084,8 +3131,7 @@ S_regmatch(pTHX_ regnode *prog)
                            UCHARAT(PL_reginput) == c1 ||
                            UCHARAT(PL_reginput) == c2)
                            {
-                               if (regmatch(next))
-                                   sayYES;
+                               TRYPAREN(paren, n, PL_reginput);
                                REGCP_UNWIND;
                            }
                        /* Couldn't or didn't -- back up. */
@@ -3587,7 +3633,11 @@ S_reginclass(pTHX_ register regnode *p, register I32 c)
            (ANYOF_CLASS_TEST(p, ANYOF_UPPER)   &&  isUPPER_LC(c))  ||
            (ANYOF_CLASS_TEST(p, ANYOF_NUPPER)  && !isUPPER_LC(c))  ||
            (ANYOF_CLASS_TEST(p, ANYOF_XDIGIT)  &&  isXDIGIT(c))    ||
-           (ANYOF_CLASS_TEST(p, ANYOF_NXDIGIT) && !isXDIGIT(c))
+           (ANYOF_CLASS_TEST(p, ANYOF_NXDIGIT) && !isXDIGIT(c))    ||
+           (ANYOF_CLASS_TEST(p, ANYOF_PSXSPC)  &&  isPSXSPC(c))    ||
+           (ANYOF_CLASS_TEST(p, ANYOF_NPSXSPC) && !isPSXSPC(c))    ||
+           (ANYOF_CLASS_TEST(p, ANYOF_BLANK)   &&  isBLANK(c))    ||
+           (ANYOF_CLASS_TEST(p, ANYOF_NBLANK)  && !isBLANK(c))
            ) /* How's that for a conditional? */
        {
            match = TRUE;
@@ -3693,4 +3743,3 @@ restore_pos(pTHXo_ void *arg)
        PL_curpm = PL_reg_oldcurpm;
     }  
 }
-