newsearch/ns-regex.c

   1 /*
   2  * REGEX functionality
   3  */
   4
   5 #include "newsearch.h"
   6
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9
  10 #include <pcre.h>
  11
  12 struct regex_localdata {
  13   struct searchNode *targnode;
  14   struct searchNode *patnode;
  15   pcre *pcre;
  16   pcre_extra *pcre_extra;
  17 };
  18
  19 void *regex_exe(struct searchNode *thenode, int type, void *theinput);
  20 void regex_free(struct searchNode *thenode);
  21
  22 struct searchNode *regex_parse(int type, int argc, char **argv) {
  23   struct regex_localdata *localdata;
  24   struct searchNode *thenode;
  25   struct searchNode *targnode, *patnode;
  26   const char *err;
  27   int erroffset;
  28   pcre *pcre;
  29   pcre_extra *pcre_extra;
  30
  31   if (argc<2) {
  32     parseError="regex: usage: regex source pattern";
  33     return NULL;
  34   }
  35
  36   if (!(targnode = search_parse(type, argv[0])))
  37     return NULL;
  38
  39   if (!(patnode = search_parse(type, argv[1]))) {
  40     (targnode->free)(targnode);
  41     return NULL;
  42   }
  43
  44   if (!(patnode->returntype & RETURNTYPE_CONST)) {
  45     parseError="regex: only constant regexes allowed";
  46     (targnode->free)(targnode);
  47     (patnode->free)(patnode);
  48     return NULL;
  49   }
  50
  51   if (!(pcre=pcre_compile((char *)(patnode->exe)(patnode,RETURNTYPE_STRING,NULL),
  52                           PCRE_CASELESS, &err, &erroffset, NULL))) {
  53     parseError=err;
  54     return NULL;
  55   }
  56
  57   pcre_extra=pcre_study(pcre, 0, &err);
  58
  59   localdata=(struct regex_localdata *)malloc(sizeof (struct regex_localdata));
  60
  61   localdata->targnode=targnode;
  62   localdata->patnode=patnode;
  63   localdata->pcre=pcre;
  64   localdata->pcre_extra=pcre_extra;
  65
  66   thenode = (struct searchNode *)malloc(sizeof (struct searchNode));
  67
  68   thenode->returntype = RETURNTYPE_BOOL;
  69   thenode->localdata = localdata;
  70   thenode->exe = regex_exe;
  71   thenode->free = regex_free;
  72
  73   return thenode;
  74 }
  75
  76 void *regex_exe(struct searchNode *thenode, int type, void *theinput) {
  77   struct regex_localdata *localdata;
  78   char *target;
  79
  80   localdata = thenode->localdata;
  81
  82   target  = (char *)((localdata->targnode->exe)(localdata->targnode,RETURNTYPE_STRING, theinput));
  83
  84   if (pcre_exec(localdata->pcre, localdata->pcre_extra,target,strlen(target),0,
  85                 0,NULL,0)) {
  86     /* didn't match */
  87     return falseval(type);
  88   } else {
  89     return trueval(type);
  90   }
  91 }
  92
  93 void regex_free(struct searchNode *thenode) {
  94   struct regex_localdata *localdata;
  95
  96   localdata=thenode->localdata;
  97
  98   if (localdata->pcre_extra)
  99     pcre_free(localdata->pcre_extra);
 100
 101   if (localdata->pcre)
 102     pcre_free(localdata->pcre);
 103
 104   (localdata->patnode->free)(localdata->patnode);
 105   (localdata->targnode->free)(localdata->targnode);
 106   free(localdata);
 107   free(thenode);
 108 }
 109