/[pcre]/code/trunk/pcre_study.c
ViewVC logotype

Diff of /code/trunk/pcre_study.c

Parent Directory Parent Directory | Revision Log Revision Log | View Patch Patch

revision 550 by ph10, Sun Oct 10 16:24:11 2010 UTC revision 697 by ph10, Mon Sep 19 12:28:24 2011 UTC
# Line 52  supporting functions. */ Line 52  supporting functions. */
52    
53  /* Returns from set_start_bits() */  /* Returns from set_start_bits() */
54    
55  enum { SSB_FAIL, SSB_DONE, SSB_CONTINUE };  enum { SSB_FAIL, SSB_DONE, SSB_CONTINUE, SSB_UNKNOWN };
56    
57    
58    
# Line 66  string of that length that matches. In U Line 66  string of that length that matches. In U
66  rather than bytes.  rather than bytes.
67    
68  Arguments:  Arguments:
69    code       pointer to start of group (the bracket)    code            pointer to start of group (the bracket)
70    startcode  pointer to start of the whole pattern    startcode       pointer to start of the whole pattern
71    options    the compiling options    options         the compiling options
72      int             RECURSE depth
73    
74  Returns:   the minimum length  Returns:   the minimum length
75             -1 if \C was encountered             -1 if \C in UTF-8 mode or (*ACCEPT) was encountered
76             -2 internal error (missing capturing bracket)             -2 internal error (missing capturing bracket)
77               -3 internal error (opcode not listed)
78  */  */
79    
80  static int  static int
81  find_minlength(const uschar *code, const uschar *startcode, int options)  find_minlength(const uschar *code, const uschar *startcode, int options,
82      int recurse_depth)
83  {  {
84  int length = -1;  int length = -1;
85  BOOL utf8 = (options & PCRE_UTF8) != 0;  BOOL utf8 = (options & PCRE_UTF8) != 0;
# Line 84  BOOL had_recurse = FALSE; Line 87  BOOL had_recurse = FALSE;
87  register int branchlength = 0;  register int branchlength = 0;
88  register uschar *cc = (uschar *)code + 1 + LINK_SIZE;  register uschar *cc = (uschar *)code + 1 + LINK_SIZE;
89    
90  if (*code == OP_CBRA || *code == OP_SCBRA) cc += 2;  if (*code == OP_CBRA || *code == OP_SCBRA ||
91        *code == OP_CBRAPOS || *code == OP_SCBRAPOS) cc += 2;
92    
93  /* Scan along the opcodes for this branch. If we get to the end of the  /* Scan along the opcodes for this branch. If we get to the end of the
94  branch, check the length against that of the other branches. */  branch, check the length against that of the other branches. */
# Line 118  for (;;) Line 122  for (;;)
122      case OP_SCBRA:      case OP_SCBRA:
123      case OP_BRA:      case OP_BRA:
124      case OP_SBRA:      case OP_SBRA:
125        case OP_CBRAPOS:
126        case OP_SCBRAPOS:
127        case OP_BRAPOS:
128        case OP_SBRAPOS:
129      case OP_ONCE:      case OP_ONCE:
130      d = find_minlength(cc, startcode, options);      d = find_minlength(cc, startcode, options, recurse_depth);
131      if (d < 0) return d;      if (d < 0) return d;
132      branchlength += d;      branchlength += d;
133      do cc += GET(cc, 1); while (*cc == OP_ALT);      do cc += GET(cc, 1); while (*cc == OP_ALT);
134      cc += 1 + LINK_SIZE;      cc += 1 + LINK_SIZE;
135      break;      break;
136    
137      /* Reached end of a branch; if it's a ket it is the end of a nested      /* ACCEPT makes things far too complicated; we have to give up. */
138      call. If it's ALT it is an alternation in a nested call. If it is  
139      END it's the end of the outer call. All can be handled by the same code. */      case OP_ACCEPT:
140        case OP_ASSERT_ACCEPT:
141        return -1;
142    
143        /* Reached end of a branch; if it's a ket it is the end of a nested
144        call. If it's ALT it is an alternation in a nested call. If it is END it's
145        the end of the outer call. All can be handled by the same code. If an
146        ACCEPT was previously encountered, use the length that was in force at that
147        time, and pass back the shortest ACCEPT length. */
148    
149      case OP_ALT:      case OP_ALT:
150      case OP_KET:      case OP_KET:
151      case OP_KETRMAX:      case OP_KETRMAX:
152      case OP_KETRMIN:      case OP_KETRMIN:
153        case OP_KETRPOS:
154      case OP_END:      case OP_END:
155      if (length < 0 || (!had_recurse && branchlength < length))      if (length < 0 || (!had_recurse && branchlength < length))
156        length = branchlength;        length = branchlength;
157      if (*cc != OP_ALT) return length;      if (op != OP_ALT) return length;
158      cc += 1 + LINK_SIZE;      cc += 1 + LINK_SIZE;
159      branchlength = 0;      branchlength = 0;
160      had_recurse = FALSE;      had_recurse = FALSE;
# Line 160  for (;;) Line 177  for (;;)
177      case OP_RREF:      case OP_RREF:
178      case OP_NRREF:      case OP_NRREF:
179      case OP_DEF:      case OP_DEF:
     case OP_OPT:  
180      case OP_CALLOUT:      case OP_CALLOUT:
181      case OP_SOD:      case OP_SOD:
182      case OP_SOM:      case OP_SOM:
183      case OP_EOD:      case OP_EOD:
184      case OP_EODN:      case OP_EODN:
185      case OP_CIRC:      case OP_CIRC:
186        case OP_CIRCM:
187      case OP_DOLL:      case OP_DOLL:
188        case OP_DOLLM:
189      case OP_NOT_WORD_BOUNDARY:      case OP_NOT_WORD_BOUNDARY:
190      case OP_WORD_BOUNDARY:      case OP_WORD_BOUNDARY:
191      cc += _pcre_OP_lengths[*cc];      cc += _pcre_OP_lengths[*cc];
# Line 177  for (;;) Line 195  for (;;)
195    
196      case OP_BRAZERO:      case OP_BRAZERO:
197      case OP_BRAMINZERO:      case OP_BRAMINZERO:
198        case OP_BRAPOSZERO:
199      case OP_SKIPZERO:      case OP_SKIPZERO:
200      cc += _pcre_OP_lengths[*cc];      cc += _pcre_OP_lengths[*cc];
201      do cc += GET(cc, 1); while (*cc == OP_ALT);      do cc += GET(cc, 1); while (*cc == OP_ALT);
# Line 186  for (;;) Line 205  for (;;)
205      /* Handle literal characters and + repetitions */      /* Handle literal characters and + repetitions */
206    
207      case OP_CHAR:      case OP_CHAR:
208      case OP_CHARNC:      case OP_CHARI:
209      case OP_NOT:      case OP_NOT:
210        case OP_NOTI:
211      case OP_PLUS:      case OP_PLUS:
212        case OP_PLUSI:
213      case OP_MINPLUS:      case OP_MINPLUS:
214        case OP_MINPLUSI:
215      case OP_POSPLUS:      case OP_POSPLUS:
216        case OP_POSPLUSI:
217      case OP_NOTPLUS:      case OP_NOTPLUS:
218        case OP_NOTPLUSI:
219      case OP_NOTMINPLUS:      case OP_NOTMINPLUS:
220        case OP_NOTMINPLUSI:
221      case OP_NOTPOSPLUS:      case OP_NOTPOSPLUS:
222        case OP_NOTPOSPLUSI:
223      branchlength++;      branchlength++;
224      cc += 2;      cc += 2;
225  #ifdef SUPPORT_UTF8  #ifdef SUPPORT_UTF8
# Line 212  for (;;) Line 238  for (;;)
238      need to skip over a multibyte character in UTF8 mode.  */      need to skip over a multibyte character in UTF8 mode.  */
239    
240      case OP_EXACT:      case OP_EXACT:
241        case OP_EXACTI:
242      case OP_NOTEXACT:      case OP_NOTEXACT:
243        case OP_NOTEXACTI:
244      branchlength += GET2(cc,1);      branchlength += GET2(cc,1);
245      cc += 4;      cc += 4;
246  #ifdef SUPPORT_UTF8  #ifdef SUPPORT_UTF8
# Line 249  for (;;) Line 277  for (;;)
277      cc++;      cc++;
278      break;      break;
279    
280      /* "Any newline" might match two characters */      /* "Any newline" might match two characters, but it also might match just
281        one. */
282    
283      case OP_ANYNL:      case OP_ANYNL:
284      branchlength += 2;      branchlength += 1;
285      cc++;      cc++;
286      break;      break;
287    
# Line 337  for (;;) Line 366  for (;;)
366      that case we must set the minimum length to zero. */      that case we must set the minimum length to zero. */
367    
368      case OP_REF:      case OP_REF:
369        case OP_REFI:
370      if ((options & PCRE_JAVASCRIPT_COMPAT) == 0)      if ((options & PCRE_JAVASCRIPT_COMPAT) == 0)
371        {        {
372        ce = cs = (uschar *)_pcre_find_bracket(startcode, utf8, GET2(cc, 1));        ce = cs = (uschar *)_pcre_find_bracket(startcode, utf8, GET2(cc, 1));
# Line 347  for (;;) Line 377  for (;;)
377          d = 0;          d = 0;
378          had_recurse = TRUE;          had_recurse = TRUE;
379          }          }
380        else d = find_minlength(cs, startcode, options);        else
381            {
382            d = find_minlength(cs, startcode, options, recurse_depth);
383            }
384        }        }
385      else d = 0;      else d = 0;
386      cc += 3;      cc += 3;
# Line 364  for (;;) Line 397  for (;;)
397        cc++;        cc++;
398        break;        break;
399    
400          case OP_CRPLUS:
401          case OP_CRMINPLUS:
402          min = 1;
403          cc++;
404          break;
405    
406        case OP_CRRANGE:        case OP_CRRANGE:
407        case OP_CRMINRANGE:        case OP_CRMINRANGE:
408        min = GET2(cc, 1);        min = GET2(cc, 1);
# Line 378  for (;;) Line 417  for (;;)
417      branchlength += min * d;      branchlength += min * d;
418      break;      break;
419    
420        /* We can easily detect direct recursion, but not mutual recursion. This is
421        caught by a recursion depth count. */
422    
423      case OP_RECURSE:      case OP_RECURSE:
424      cs = ce = (uschar *)startcode + GET(cc, 1);      cs = ce = (uschar *)startcode + GET(cc, 1);
425      if (cs == NULL) return -2;      if (cs == NULL) return -2;
426      do ce += GET(ce, 1); while (*ce == OP_ALT);      do ce += GET(ce, 1); while (*ce == OP_ALT);
427      if (cc > cs && cc < ce)      if ((cc > cs && cc < ce) || recurse_depth > 10)
428        had_recurse = TRUE;        had_recurse = TRUE;
429      else      else
430        branchlength += find_minlength(cs, startcode, options);        {
431          branchlength += find_minlength(cs, startcode, options, recurse_depth + 1);
432          }
433      cc += 1 + LINK_SIZE;      cc += 1 + LINK_SIZE;
434      break;      break;
435    
436      /* Anything else does not or need not match a character. We can get the      /* Anything else does not or need not match a character. We can get the
437      item's length from the table, but for those that can match zero occurrences      item's length from the table, but for those that can match zero occurrences
438      of a character, we must take special action for UTF-8 characters. */      of a character, we must take special action for UTF-8 characters. As it
439        happens, the "NOT" versions of these opcodes are used at present only for
440        ASCII characters, so they could be omitted from this list. However, in
441        future that may change, so we include them here so as not to leave a
442        gotcha for a future maintainer. */
443    
444      case OP_UPTO:      case OP_UPTO:
445        case OP_UPTOI:
446      case OP_NOTUPTO:      case OP_NOTUPTO:
447        case OP_NOTUPTOI:
448      case OP_MINUPTO:      case OP_MINUPTO:
449        case OP_MINUPTOI:
450      case OP_NOTMINUPTO:      case OP_NOTMINUPTO:
451        case OP_NOTMINUPTOI:
452      case OP_POSUPTO:      case OP_POSUPTO:
453        case OP_POSUPTOI:
454        case OP_NOTPOSUPTO:
455        case OP_NOTPOSUPTOI:
456    
457      case OP_STAR:      case OP_STAR:
458        case OP_STARI:
459        case OP_NOTSTAR:
460        case OP_NOTSTARI:
461      case OP_MINSTAR:      case OP_MINSTAR:
462        case OP_MINSTARI:
463      case OP_NOTMINSTAR:      case OP_NOTMINSTAR:
464        case OP_NOTMINSTARI:
465      case OP_POSSTAR:      case OP_POSSTAR:
466        case OP_POSSTARI:
467      case OP_NOTPOSSTAR:      case OP_NOTPOSSTAR:
468        case OP_NOTPOSSTARI:
469    
470      case OP_QUERY:      case OP_QUERY:
471        case OP_QUERYI:
472        case OP_NOTQUERY:
473        case OP_NOTQUERYI:
474      case OP_MINQUERY:      case OP_MINQUERY:
475        case OP_MINQUERYI:
476      case OP_NOTMINQUERY:      case OP_NOTMINQUERY:
477        case OP_NOTMINQUERYI:
478      case OP_POSQUERY:      case OP_POSQUERY:
479        case OP_POSQUERYI:
480      case OP_NOTPOSQUERY:      case OP_NOTPOSQUERY:
481        case OP_NOTPOSQUERYI:
482    
483      cc += _pcre_OP_lengths[op];      cc += _pcre_OP_lengths[op];
484  #ifdef SUPPORT_UTF8  #ifdef SUPPORT_UTF8
485      if (utf8 && cc[-1] >= 0xc0) cc += _pcre_utf8_table4[cc[-1] & 0x3f];      if (utf8 && cc[-1] >= 0xc0) cc += _pcre_utf8_table4[cc[-1] & 0x3f];
# Line 426  for (;;) Line 498  for (;;)
498      cc += _pcre_OP_lengths[op] + cc[1+LINK_SIZE];      cc += _pcre_OP_lengths[op] + cc[1+LINK_SIZE];
499      break;      break;
500    
501      /* For the record, these are the opcodes that are matched by "default":      /* The remaining opcodes are just skipped over. */
     OP_ACCEPT, OP_CLOSE, OP_COMMIT, OP_FAIL, OP_PRUNE, OP_SET_SOM, OP_SKIP,  
     OP_THEN. */  
502    
503      default:      case OP_CLOSE:
504        case OP_COMMIT:
505        case OP_FAIL:
506        case OP_PRUNE:
507        case OP_SET_SOM:
508        case OP_SKIP:
509        case OP_THEN:
510      cc += _pcre_OP_lengths[op];      cc += _pcre_OP_lengths[op];
511      break;      break;
512    
513        /* This should not occur: we list all opcodes explicitly so that when
514        new ones get added they are properly considered. */
515    
516        default:
517        return -3;
518      }      }
519    }    }
520  /* Control never gets here */  /* Control never gets here */
# Line 578  function fails unless the result is SSB_ Line 660  function fails unless the result is SSB_
660  Arguments:  Arguments:
661    code         points to an expression    code         points to an expression
662    start_bits   points to a 32-byte table, initialized to 0    start_bits   points to a 32-byte table, initialized to 0
   caseless     the current state of the caseless flag  
663    utf8         TRUE if in UTF-8 mode    utf8         TRUE if in UTF-8 mode
664    cd           the block with char table pointers    cd           the block with char table pointers
665    
666  Returns:       SSB_FAIL     => Failed to find any starting bytes  Returns:       SSB_FAIL     => Failed to find any starting bytes
667                 SSB_DONE     => Found mandatory starting bytes                 SSB_DONE     => Found mandatory starting bytes
668                 SSB_CONTINUE => Found optional starting bytes                 SSB_CONTINUE => Found optional starting bytes
669                   SSB_UNKNOWN  => Hit an unrecognized opcode
670  */  */
671    
672  static int  static int
673  set_start_bits(const uschar *code, uschar *start_bits, BOOL caseless,  set_start_bits(const uschar *code, uschar *start_bits, BOOL utf8,
674    BOOL utf8, compile_data *cd)    compile_data *cd)
675  {  {
676  register int c;  register int c;
677  int yield = SSB_DONE;  int yield = SSB_DONE;
# Line 614  volatile int dummy; Line 696  volatile int dummy;
696    
697  do  do
698    {    {
   const uschar *tcode = code + (((int)*code == OP_CBRA)? 3:1) + LINK_SIZE;  
699    BOOL try_next = TRUE;    BOOL try_next = TRUE;
700      const uschar *tcode = code + 1 + LINK_SIZE;
701    
702      if (*code == OP_CBRA || *code == OP_SCBRA ||
703          *code == OP_CBRAPOS || *code == OP_SCBRAPOS) tcode += 2;
704    
705    while (try_next)    /* Loop for items in this branch */    while (try_next)    /* Loop for items in this branch */
706      {      {
707      int rc;      int rc;
708    
709      switch(*tcode)      switch(*tcode)
710        {        {
711        /* Fail if we reach something we don't understand */        /* If we reach something we don't understand, it means a new opcode has
712          been created that hasn't been added to this code. Hopefully this problem
713          will be discovered during testing. */
714    
715        default:        default:
716          return SSB_UNKNOWN;
717    
718          /* Fail for a valid opcode that implies no starting bits. */
719    
720          case OP_ACCEPT:
721          case OP_ASSERT_ACCEPT:
722          case OP_ALLANY:
723          case OP_ANY:
724          case OP_ANYBYTE:
725          case OP_CIRC:
726          case OP_CIRCM:
727          case OP_CLOSE:
728          case OP_COMMIT:
729          case OP_COND:
730          case OP_CREF:
731          case OP_DEF:
732          case OP_DOLL:
733          case OP_DOLLM:
734          case OP_END:
735          case OP_EOD:
736          case OP_EODN:
737          case OP_EXTUNI:
738          case OP_FAIL:
739          case OP_MARK:
740          case OP_NCREF:
741          case OP_NOT:
742          case OP_NOTEXACT:
743          case OP_NOTEXACTI:
744          case OP_NOTI:
745          case OP_NOTMINPLUS:
746          case OP_NOTMINPLUSI:
747          case OP_NOTMINQUERY:
748          case OP_NOTMINQUERYI:
749          case OP_NOTMINSTAR:
750          case OP_NOTMINSTARI:
751          case OP_NOTMINUPTO:
752          case OP_NOTMINUPTOI:
753          case OP_NOTPLUS:
754          case OP_NOTPLUSI:
755          case OP_NOTPOSPLUS:
756          case OP_NOTPOSPLUSI:
757          case OP_NOTPOSQUERY:
758          case OP_NOTPOSQUERYI:
759          case OP_NOTPOSSTAR:
760          case OP_NOTPOSSTARI:
761          case OP_NOTPOSUPTO:
762          case OP_NOTPOSUPTOI:
763          case OP_NOTPROP:
764          case OP_NOTQUERY:
765          case OP_NOTQUERYI:
766          case OP_NOTSTAR:
767          case OP_NOTSTARI:
768          case OP_NOTUPTO:
769          case OP_NOTUPTOI:
770          case OP_NOT_HSPACE:
771          case OP_NOT_VSPACE:
772          case OP_NRREF:
773          case OP_PROP:
774          case OP_PRUNE:
775          case OP_PRUNE_ARG:
776          case OP_RECURSE:
777          case OP_REF:
778          case OP_REFI:
779          case OP_REVERSE:
780          case OP_RREF:
781          case OP_SCOND:
782          case OP_SET_SOM:
783          case OP_SKIP:
784          case OP_SKIP_ARG:
785          case OP_SOD:
786          case OP_SOM:
787          case OP_THEN:
788          case OP_THEN_ARG:
789          case OP_XCLASS:
790        return SSB_FAIL;        return SSB_FAIL;
791    
792          /* We can ignore word boundary tests. */
793    
794          case OP_WORD_BOUNDARY:
795          case OP_NOT_WORD_BOUNDARY:
796          tcode++;
797          break;
798    
799        /* If we hit a bracket or a positive lookahead assertion, recurse to set        /* If we hit a bracket or a positive lookahead assertion, recurse to set
800        bits from within the subpattern. If it can't find anything, we have to        bits from within the subpattern. If it can't find anything, we have to
801        give up. If it finds some mandatory character(s), we are done for this        give up. If it finds some mandatory character(s), we are done for this
# Line 636  do Line 805  do
805        case OP_SBRA:        case OP_SBRA:
806        case OP_CBRA:        case OP_CBRA:
807        case OP_SCBRA:        case OP_SCBRA:
808          case OP_BRAPOS:
809          case OP_SBRAPOS:
810          case OP_CBRAPOS:
811          case OP_SCBRAPOS:
812        case OP_ONCE:        case OP_ONCE:
813        case OP_ASSERT:        case OP_ASSERT:
814        rc = set_start_bits(tcode, start_bits, caseless, utf8, cd);        rc = set_start_bits(tcode, start_bits, utf8, cd);
815        if (rc == SSB_FAIL) return SSB_FAIL;        if (rc == SSB_FAIL || rc == SSB_UNKNOWN) return rc;
816        if (rc == SSB_DONE) try_next = FALSE; else        if (rc == SSB_DONE) try_next = FALSE; else
817          {          {
818          do tcode += GET(tcode, 1); while (*tcode == OP_ALT);          do tcode += GET(tcode, 1); while (*tcode == OP_ALT);
# Line 662  do Line 835  do
835        case OP_KET:        case OP_KET:
836        case OP_KETRMAX:        case OP_KETRMAX:
837        case OP_KETRMIN:        case OP_KETRMIN:
838          case OP_KETRPOS:
839        return SSB_CONTINUE;        return SSB_CONTINUE;
840    
841        /* Skip over callout */        /* Skip over callout */
# Line 679  do Line 853  do
853        tcode += 1 + LINK_SIZE;        tcode += 1 + LINK_SIZE;
854        break;        break;
855    
       /* Skip over an option setting, changing the caseless flag */  
   
       case OP_OPT:  
       caseless = (tcode[1] & PCRE_CASELESS) != 0;  
       tcode += 2;  
       break;  
   
856        /* BRAZERO does the bracket, but carries on. */        /* BRAZERO does the bracket, but carries on. */
857    
858        case OP_BRAZERO:        case OP_BRAZERO:
859        case OP_BRAMINZERO:        case OP_BRAMINZERO:
860        if (set_start_bits(++tcode, start_bits, caseless, utf8, cd) == SSB_FAIL)        case OP_BRAPOSZERO:
861          return SSB_FAIL;        rc = set_start_bits(++tcode, start_bits, utf8, cd);
862          if (rc == SSB_FAIL || rc == SSB_UNKNOWN) return rc;
863  /* =========================================================================  /* =========================================================================
864        See the comment at the head of this function concerning the next line,        See the comment at the head of this function concerning the next line,
865        which was an old fudge for the benefit of OS/2.        which was an old fudge for the benefit of OS/2.
# Line 717  do Line 885  do
885        case OP_QUERY:        case OP_QUERY:
886        case OP_MINQUERY:        case OP_MINQUERY:
887        case OP_POSQUERY:        case OP_POSQUERY:
888        tcode = set_table_bit(start_bits, tcode + 1, caseless, cd, utf8);        tcode = set_table_bit(start_bits, tcode + 1, FALSE, cd, utf8);
889          break;
890    
891          case OP_STARI:
892          case OP_MINSTARI:
893          case OP_POSSTARI:
894          case OP_QUERYI:
895          case OP_MINQUERYI:
896          case OP_POSQUERYI:
897          tcode = set_table_bit(start_bits, tcode + 1, TRUE, cd, utf8);
898        break;        break;
899    
900        /* Single-char upto sets the bit and tries the next */        /* Single-char upto sets the bit and tries the next */
# Line 725  do Line 902  do
902        case OP_UPTO:        case OP_UPTO:
903        case OP_MINUPTO:        case OP_MINUPTO:
904        case OP_POSUPTO:        case OP_POSUPTO:
905        tcode = set_table_bit(start_bits, tcode + 3, caseless, cd, utf8);        tcode = set_table_bit(start_bits, tcode + 3, FALSE, cd, utf8);
906          break;
907    
908          case OP_UPTOI:
909          case OP_MINUPTOI:
910          case OP_POSUPTOI:
911          tcode = set_table_bit(start_bits, tcode + 3, TRUE, cd, utf8);
912        break;        break;
913    
914        /* At least one single char sets the bit and stops */        /* At least one single char sets the bit and stops */
915    
916        case OP_EXACT:       /* Fall through */        case OP_EXACT:
917        tcode += 2;        tcode += 2;
918          /* Fall through */
919        case OP_CHAR:        case OP_CHAR:
       case OP_CHARNC:  
920        case OP_PLUS:        case OP_PLUS:
921        case OP_MINPLUS:        case OP_MINPLUS:
922        case OP_POSPLUS:        case OP_POSPLUS:
923        (void)set_table_bit(start_bits, tcode + 1, caseless, cd, utf8);        (void)set_table_bit(start_bits, tcode + 1, FALSE, cd, utf8);
924          try_next = FALSE;
925          break;
926    
927          case OP_EXACTI:
928          tcode += 2;
929          /* Fall through */
930          case OP_CHARI:
931          case OP_PLUSI:
932          case OP_MINPLUSI:
933          case OP_POSPLUSI:
934          (void)set_table_bit(start_bits, tcode + 1, TRUE, cd, utf8);
935        try_next = FALSE;        try_next = FALSE;
936        break;        break;
937    
# Line 968  do Line 1161  do
1161            for (c = 0; c < 32; c++) start_bits[c] |= tcode[c];            for (c = 0; c < 32; c++) start_bits[c] |= tcode[c];
1162            }            }
1163    
1164          /* Advance past the bit map, and act on what follows */          /* Advance past the bit map, and act on what follows. For a zero
1165            minimum repeat, continue; otherwise stop processing. */
1166    
1167          tcode += 32;          tcode += 32;
1168          switch (*tcode)          switch (*tcode)
# Line 1004  return yield; Line 1198  return yield;
1198    
1199    
1200    
1201    
1202    
1203  /*************************************************  /*************************************************
1204  *          Study a compiled expression           *  *          Study a compiled expression           *
1205  *************************************************/  *************************************************/
# Line 1029  pcre_study(const pcre *external_re, int Line 1225  pcre_study(const pcre *external_re, int
1225  int min;  int min;
1226  BOOL bits_set = FALSE;  BOOL bits_set = FALSE;
1227  uschar start_bits[32];  uschar start_bits[32];
1228  pcre_extra *extra;  pcre_extra *extra = NULL;
1229  pcre_study_data *study;  pcre_study_data *study;
1230  const uschar *tables;  const uschar *tables;
1231  uschar *code;  uschar *code;
# Line 1060  seeking a list of starting bytes. */ Line 1256  seeking a list of starting bytes. */
1256  if ((re->options & PCRE_ANCHORED) == 0 &&  if ((re->options & PCRE_ANCHORED) == 0 &&
1257      (re->flags & (PCRE_FIRSTSET|PCRE_STARTLINE)) == 0)      (re->flags & (PCRE_FIRSTSET|PCRE_STARTLINE)) == 0)
1258    {    {
1259      int rc;
1260    
1261    /* Set the character tables in the block that is passed around */    /* Set the character tables in the block that is passed around */
1262    
1263    tables = re->tables;    tables = re->tables;
# Line 1075  if ((re->options & PCRE_ANCHORED) == 0 & Line 1273  if ((re->options & PCRE_ANCHORED) == 0 &
1273    /* See if we can find a fixed set of initial characters for the pattern. */    /* See if we can find a fixed set of initial characters for the pattern. */
1274    
1275    memset(start_bits, 0, 32 * sizeof(uschar));    memset(start_bits, 0, 32 * sizeof(uschar));
1276    bits_set = set_start_bits(code, start_bits,    rc = set_start_bits(code, start_bits, (re->options & PCRE_UTF8) != 0,
1277      (re->options & PCRE_CASELESS) != 0, (re->options & PCRE_UTF8) != 0,      &compile_block);
1278      &compile_block) == SSB_DONE;    bits_set = rc == SSB_DONE;
1279      if (rc == SSB_UNKNOWN)
1280        {
1281        *errorptr = "internal error: opcode not recognized";
1282        return NULL;
1283        }
1284    }    }
1285    
1286  /* Find the minimum length of subject string. */  /* Find the minimum length of subject string. */
1287    
1288  min = find_minlength(code, code, re->options);  switch(min = find_minlength(code, code, re->options, 0))
1289      {
1290      case -2: *errorptr = "internal error: missing capturing bracket"; return NULL;
1291      case -3: *errorptr = "internal error: opcode not recognized"; return NULL;
1292      default: break;
1293      }
1294    
1295    /* If a set of starting bytes has been identified, or if the minimum length is
1296    greater than zero, or if JIT optimization has been requested, get a pcre_extra
1297    block and a pcre_study_data block. The study data is put in the latter, which
1298    is pointed to by the former, which may also get additional data set later by
1299    the calling program. At the moment, the size of pcre_study_data is fixed. We
1300    nevertheless save it in a field for returning via the pcre_fullinfo() function
1301    so that if it becomes variable in the future, we don't have to change that
1302    code. */
1303    
1304    if (bits_set || min > 0
1305    #ifdef SUPPORT_JIT
1306        || (options & PCRE_STUDY_JIT_COMPILE) != 0
1307    #endif
1308      )
1309      {
1310      extra = (pcre_extra *)(pcre_malloc)
1311        (sizeof(pcre_extra) + sizeof(pcre_study_data));
1312      if (extra == NULL)
1313        {
1314        *errorptr = "failed to get memory";
1315        return NULL;
1316        }
1317    
1318  /* Return NULL if no optimization is possible. */    study = (pcre_study_data *)((char *)extra + sizeof(pcre_extra));
1319      extra->flags = PCRE_EXTRA_STUDY_DATA;
1320      extra->study_data = study;
1321    
1322  if (!bits_set && min < 0) return NULL;    study->size = sizeof(pcre_study_data);
1323      study->flags = 0;
1324    
1325  /* Get a pcre_extra block and a pcre_study_data block. The study data is put in    if (bits_set)
1326  the latter, which is pointed to by the former, which may also get additional      {
1327  data set later by the calling program. At the moment, the size of      study->flags |= PCRE_STUDY_MAPPED;
1328  pcre_study_data is fixed. We nevertheless save it in a field for returning via      memcpy(study->start_bits, start_bits, sizeof(start_bits));
1329  the pcre_fullinfo() function so that if it becomes variable in the future, we      }
 don't have to change that code. */  
1330    
1331  extra = (pcre_extra *)(pcre_malloc)    /* Always set the minlength value in the block, because the JIT compiler
1332    (sizeof(pcre_extra) + sizeof(pcre_study_data));    makes use of it. However, don't set the bit unless the length is greater than
1333      zero - the interpretive pcre_exec() and pcre_dfa_exec() needn't waste time
1334      checking the zero case. */
1335    
1336  if (extra == NULL)    if (min > 0)
1337    {      {
1338    *errorptr = "failed to get memory";      study->flags |= PCRE_STUDY_MINLEN;
1339    return NULL;      study->minlength = min;
1340        }
1341      else study->minlength = 0;
1342    
1343      /* If JIT support was compiled and requested, attempt the JIT compilation.
1344      If no starting bytes were found, and the minimum length is zero, and JIT
1345      compilation fails, abandon the extra block and return NULL. */
1346    
1347    #ifdef SUPPORT_JIT
1348      extra->executable_jit = NULL;
1349      if ((options & PCRE_STUDY_JIT_COMPILE) != 0) _pcre_jit_compile(re, extra);
1350      if (study->flags == 0 && (extra->flags & PCRE_EXTRA_EXECUTABLE_JIT) == 0)
1351        {
1352        pcre_free_study(extra);
1353        extra = NULL;
1354        }
1355    #endif
1356    }    }
1357    
1358  study = (pcre_study_data *)((char *)extra + sizeof(pcre_extra));  return extra;
1359  extra->flags = PCRE_EXTRA_STUDY_DATA;  }
 extra->study_data = study;  
1360    
 study->size = sizeof(pcre_study_data);  
 study->flags = 0;  
1361    
1362  if (bits_set)  /*************************************************
1363    {  *          Free the study data                   *
1364    study->flags |= PCRE_STUDY_MAPPED;  *************************************************/
   memcpy(study->start_bits, start_bits, sizeof(start_bits));  
   }  
1365    
1366  if (min >= 0)  /* This function frees the memory that was obtained by pcre_study().
   {  
   study->flags |= PCRE_STUDY_MINLEN;  
   study->minlength = min;  
   }  
1367    
1368  return extra;  Argument:   a pointer to the pcre_extra block
1369    Returns:    nothing
1370    */
1371    
1372    PCRE_EXP_DEFN void
1373    pcre_free_study(pcre_extra *extra)
1374    {
1375    #ifdef SUPPORT_JIT
1376    if ((extra->flags & PCRE_EXTRA_EXECUTABLE_JIT) != 0 &&
1377         extra->executable_jit != NULL)
1378      _pcre_jit_free(extra->executable_jit);
1379    #endif
1380    pcre_free(extra);
1381  }  }
1382    
1383  /* End of pcre_study.c */  /* End of pcre_study.c */
Legend:
Removed from v.550  
changed lines
  Added in v.697
webmaster@exim.org
 ViewVC Help
Powered by ViewVC 1.1.12