external/bsd/openldap/dist/libraries/librewrite/info.c

   1 /* $OpenLDAP: pkg/ldap/libraries/librewrite/info.c,v 1.15.2.3 2008/02/11 23:26:42 kurt Exp $ */
   2 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
   3  *
   4  * Copyright 2000-2008 The OpenLDAP Foundation.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted only as authorized by the OpenLDAP
   9  * Public License.
  10  *
  11  * A copy of this license is available in the file LICENSE in the
  12  * top-level directory of the distribution or, alternatively, at
  13  * <http://www.OpenLDAP.org/license.html>.
  14  */
  15 /* ACKNOWLEDGEMENT:
  16  * This work was initially developed by Pierangelo Masarati for
  17  * inclusion in OpenLDAP Software.
  18  */
  19
  20 #include <portable.h>
  21
  22 #include "rewrite-int.h"
  23
  24 /*
  25  * Global data
  26  */
  27
  28 /*
  29  * This becomes the running context for subsequent calls to
  30  * rewrite_parse; it can be altered only by a
  31  * rewriteContext config line or by a change in info.
  32  */
  33 struct rewrite_context *rewrite_int_curr_context = NULL;
  34
  35 /*
  36  * Inits the info
  37  */
  38 struct rewrite_info *
  39 rewrite_info_init(
  40                 int mode
  41 )
  42 {
  43         struct rewrite_info *info;
  44         struct rewrite_context *context;
  45
  46         switch ( mode ) {
  47         case REWRITE_MODE_ERR:
  48         case REWRITE_MODE_OK:
  49         case REWRITE_MODE_COPY_INPUT:
  50         case REWRITE_MODE_USE_DEFAULT:
  51                 break;
  52         default:
  53                 mode = REWRITE_MODE_USE_DEFAULT;
  54                 break;
  55                 /* return NULL */
  56         }
  57
  58         /*
  59          * Resets the running context for parsing ...
  60          */
  61         rewrite_int_curr_context = NULL;
  62
  63         info = calloc( sizeof( struct rewrite_info ), 1 );
  64         if ( info == NULL ) {
  65                 return NULL;
  66         }
  67
  68         info->li_state = REWRITE_DEFAULT;
  69         info->li_max_passes = REWRITE_MAX_PASSES;
  70         info->li_max_passes_per_rule = REWRITE_MAX_PASSES;
  71         info->li_rewrite_mode = mode;
  72
  73         /*
  74          * Add the default (empty) rule
  75          */
  76         context = rewrite_context_create( info, REWRITE_DEFAULT_CONTEXT );
  77         if ( context == NULL ) {
  78                 free( info );
  79                 return NULL;
  80         }
  81
  82 #ifdef USE_REWRITE_LDAP_PVT_THREADS
  83         if ( ldap_pvt_thread_rdwr_init( &info->li_cookies_mutex ) ) {
  84                 avl_free( info->li_context, rewrite_context_free );
  85                 free( info );
  86                 return NULL;
  87         }
  88         if ( ldap_pvt_thread_rdwr_init( &info->li_params_mutex ) ) {
  89                 ldap_pvt_thread_rdwr_destroy( &info->li_cookies_mutex );
  90                 avl_free( info->li_context, rewrite_context_free );
  91                 free( info );
  92                 return NULL;
  93         }
  94 #endif /* USE_REWRITE_LDAP_PVT_THREADS */
  95
  96         return info;
  97 }
  98
  99 /*
 100  * Cleans up the info structure
 101  */
 102 int
 103 rewrite_info_delete(
 104                 struct rewrite_info **pinfo
 105 )
 106 {
 107         struct rewrite_info     *info;
 108
 109         assert( pinfo != NULL );
 110         assert( *pinfo != NULL );
 111
 112         info = *pinfo;
 113
 114         if ( info->li_context ) {
 115                 avl_free( info->li_context, rewrite_context_free );
 116         }
 117         info->li_context = NULL;
 118
 119         if ( info->li_maps ) {
 120                 avl_free( info->li_maps, rewrite_builtin_map_free );
 121         }
 122         info->li_maps = NULL;
 123
 124         rewrite_session_destroy( info );
 125
 126 #ifdef USE_REWRITE_LDAP_PVT_THREADS
 127         ldap_pvt_thread_rdwr_destroy( &info->li_cookies_mutex );
 128 #endif /* USE_REWRITE_LDAP_PVT_THREADS */
 129
 130         rewrite_param_destroy( info );
 131
 132 #ifdef USE_REWRITE_LDAP_PVT_THREADS
 133         ldap_pvt_thread_rdwr_destroy( &info->li_params_mutex );
 134 #endif /* USE_REWRITE_LDAP_PVT_THREADS */
 135
 136         free( info );
 137         *pinfo = NULL;
 138
 139         return REWRITE_SUCCESS;
 140 }
 141
 142 /*
 143  * Rewrites a string according to context.
 144  * If the engine is off, OK is returned, but the return string will be NULL.
 145  * In case of 'unwilling to perform', UNWILLING is returned, and the
 146  * return string will also be null. The same in case of error.
 147  * Otherwise, OK is returned, and result will hold a newly allocated string
 148  * with the rewriting.
 149  *
 150  * What to do in case of non-existing rewrite context is still an issue.
 151  * Four possibilities:
 152  *      - error,
 153  *      - ok with NULL result,
 154  *      - ok with copy of string as result,
 155  *      - use the default rewrite context.
 156  */
 157 int
 158 rewrite(
 159                 struct rewrite_info *info,
 160                 const char *rewriteContext,
 161                 const char *string,
 162                 char **result
 163 )
 164 {
 165         return rewrite_session( info, rewriteContext,
 166                         string, NULL, result );
 167 }
 168
 169 int
 170 rewrite_session(
 171                 struct rewrite_info *info,
 172                 const char *rewriteContext,
 173                 const char *string,
 174                 const void *cookie,
 175                 char **result
 176 )
 177 {
 178         struct rewrite_context *context;
 179         struct rewrite_op op = { 0, 0, NULL, NULL, NULL };
 180         int rc;
 181
 182         assert( info != NULL );
 183         assert( rewriteContext != NULL );
 184         assert( string != NULL );
 185         assert( result != NULL );
 186
 187         /*
 188          * cookie can be null; means: don't care about session stuff
 189          */
 190
 191         *result = NULL;
 192         op.lo_cookie = cookie;
 193
 194         /*
 195          * Engine not on means no failure, but explicit no rewriting
 196          */
 197         if ( info->li_state != REWRITE_ON ) {
 198                 rc = REWRITE_REGEXEC_OK;
 199                 goto rc_return;
 200         }
 201
 202         /*
 203          * Undefined context means no rewriting also
 204          * (conservative, are we sure it's what we want?)
 205          */
 206         context = rewrite_context_find( info, rewriteContext );
 207         if ( context == NULL ) {
 208                 switch ( info->li_rewrite_mode ) {
 209                 case REWRITE_MODE_ERR:
 210                         rc = REWRITE_REGEXEC_ERR;
 211                         goto rc_return;
 212
 213                 case REWRITE_MODE_OK:
 214                         rc = REWRITE_REGEXEC_OK;
 215                         goto rc_return;
 216
 217                 case REWRITE_MODE_COPY_INPUT:
 218                         *result = strdup( string );
 219                         rc = REWRITE_REGEXEC_OK;
 220                         goto rc_return;
 221
 222                 case REWRITE_MODE_USE_DEFAULT:
 223                         context = rewrite_context_find( info,
 224                                         REWRITE_DEFAULT_CONTEXT );
 225                         break;
 226                 }
 227         }
 228
 229 #if 0 /* FIXME: not used anywhere! (debug? then, why strdup?) */
 230         op.lo_string = strdup( string );
 231         if ( op.lo_string == NULL ) {
 232                 rc = REWRITE_REGEXEC_ERR;
 233                 goto rc_return;
 234         }
 235 #endif
 236
 237         /*
 238          * Applies rewrite context
 239          */
 240         rc = rewrite_context_apply( info, &op, context, string, result );
 241         assert( op.lo_depth == 0 );
 242
 243 #if 0 /* FIXME: not used anywhere! (debug? then, why strdup?) */
 244         free( op.lo_string );
 245 #endif
 246
 247         switch ( rc ) {
 248         /*
 249          * Success
 250          */
 251         case REWRITE_REGEXEC_OK:
 252         case REWRITE_REGEXEC_STOP:
 253                 /*
 254                  * If rewrite succeeded return OK regardless of how
 255                  * the successful rewriting was obtained!
 256                  */
 257                 rc = REWRITE_REGEXEC_OK;
 258                 break;
 259
 260
 261         /*
 262          * Internal or forced error, return = NULL; rc already OK.
 263          */
 264         case REWRITE_REGEXEC_UNWILLING:
 265         case REWRITE_REGEXEC_ERR:
 266                 if ( *result != NULL ) {
 267                         if ( *result != string ) {
 268                                 free( *result );
 269                         }
 270                         *result = NULL;
 271                 }
 272
 273         default:
 274                 break;
 275         }
 276
 277 rc_return:;
 278         if ( op.lo_vars ) {
 279                 rewrite_var_delete( op.lo_vars );
 280         }
 281
 282         return rc;
 283 }
 284