lib/libform/type_regex.c

   1 /*      $NetBSD: type_regex.c,v 1.7 2004/11/24 11:57:09 blymn Exp $     */
   2
   3 /*-
   4  * Copyright (c) 1998-1999 Brett Lymn
   5  *                         (blymn@baea.com.au, brett_lymn@yahoo.com.au)
   6  * All rights reserved.
   7  *
   8  * This code has been donated to The NetBSD Foundation by the Author.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. The name of the author may not be used to endorse or promote products
  16  *    derived from this software without specific prior written permission
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  *
  29  *
  30  */
  31
  32 #include <sys/cdefs.h>
  33 __RCSID("$NetBSD: type_regex.c,v 1.7 2004/11/24 11:57:09 blymn Exp $");
  34
  35 #include <stdlib.h>
  36 #include <sys/types.h>
  37 #include <regex.h>
  38 #include "form.h"
  39 #include "internals.h"
  40
  41 /*
  42  * The regex type handling.
  43  */
  44
  45 typedef struct
  46 {
  47         regex_t compiled;
  48         unsigned references;
  49 } regex_args;
  50
  51 /*
  52  * Create the regex arguments structure from the given args.  Return NULL
  53  * if the call fails, otherwise return a pointer to the structure allocated.
  54  */
  55 static char *
  56 create_regex_args(va_list *args)
  57 {
  58         regex_args *new;
  59         char *expression;
  60
  61         new = (regex_args *) malloc(sizeof(regex_args));
  62
  63         if (new != NULL) {
  64                 new->references = 1;
  65                 expression = va_arg(*args, char *);
  66                 if ((regcomp(&new->compiled, expression,
  67                              (REG_EXTENDED | REG_NOSUB | REG_NEWLINE))) != 0) {
  68                         free(new);
  69                         return NULL;
  70                 }
  71         }
  72
  73         return (void *) new;
  74 }
  75
  76 /*
  77  * Copy the regex argument structure.
  78  */
  79 static char *
  80 copy_regex_args(char *args)
  81 {
  82         ((regex_args *) (void *) args)->references++;
  83
  84         return (void *) args;
  85 }
  86
  87 /*
  88  * Free the allocated storage associated with the type arguments.
  89  */
  90 static void
  91 free_regex_args(char *args)
  92 {
  93         if (args != NULL) {
  94                 ((regex_args *) (void *) args)->references--;
  95                 if (((regex_args *) (void *) args)->references == 0)
  96                         free(args);
  97         }
  98 }
  99
 100 /*
 101  * Check the contents of the field buffer match the regex.
 102  */
 103 static int
 104 regex_check_field(FIELD *field, char *args)
 105 {
 106         if ((args != NULL) &&
 107             (regexec(&((regex_args *) (void *) field->args)->compiled,
 108                    args, (size_t) 0, NULL, 0) == 0))
 109                 return TRUE;
 110
 111         return FALSE;
 112 }
 113
 114 static FIELDTYPE builtin_regex = {
 115         _TYPE_HAS_ARGS | _TYPE_IS_BUILTIN,  /* flags */
 116         0,                                  /* refcount */
 117         NULL,                               /* link */
 118         create_regex_args,                  /* make_args */
 119         copy_regex_args,                    /* copy_args */
 120         free_regex_args,                    /* free_args */
 121         regex_check_field,                  /* field_check */
 122         NULL,                               /* char_check */
 123         NULL,                               /* next_choice */
 124         NULL                                /* prev_choice */
 125 };
 126
 127 FIELDTYPE *TYPE_REGEXP = &builtin_regex;
 128
 129