funcs/func_cut.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * Copyright (c) 2003-2006 Tilghman Lesher.  All rights reserved.
   5  *
   6  * Tilghman Lesher <app_cut__v003@the-tilghman.com>
   7  *
   8  * This code is released by the author with no restrictions on usage.
   9  *
  10  * See http://www.asterisk.org for more information about
  11  * the Asterisk project. Please do not directly contact
  12  * any of the maintainers of this project for assistance;
  13  * the project provides a web site, mailing lists and IRC
  14  * channels for your use.
  15  *
  16  */
  17
  18 /*! \file
  19  *
  20  * \brief CUT function
  21  *
  22  * \author Tilghman Lesher <app_cut__v003@the-tilghman.com>
  23  *
  24  * \ingroup functions
  25  */
  26
  27 #include "asterisk.h"
  28
  29 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  30
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <unistd.h>
  34 #include <string.h>
  35
  36 #include "asterisk/file.h"
  37 #include "asterisk/logger.h"
  38 #include "asterisk/options.h"
  39 #include "asterisk/channel.h"
  40 #include "asterisk/pbx.h"
  41 #include "asterisk/module.h"
  42 #include "asterisk/app.h"
  43
  44 /* Maximum length of any variable */
  45 #define MAXRESULT       1024
  46
  47
  48 LOCAL_USER_DECL;
  49
  50 struct sortable_keys {
  51         char *key;
  52         float value;
  53 };
  54
  55 static int sort_subroutine(const void *arg1, const void *arg2)
  56 {
  57         const struct sortable_keys *one=arg1, *two=arg2;
  58         if (one->value < two->value)
  59                 return -1;
  60         else if (one->value == two->value)
  61                 return 0;
  62         else
  63                 return 1;
  64 }
  65
  66 #define ERROR_NOARG     (-1)
  67 #define ERROR_NOMEM     (-2)
  68 #define ERROR_USAGE     (-3)
  69
  70 static int sort_internal(struct ast_channel *chan, char *data, char *buffer, size_t buflen)
  71 {
  72         char *strings, *ptrkey, *ptrvalue;
  73         int count=1, count2, element_count=0;
  74         struct sortable_keys *sortable_keys;
  75
  76         memset(buffer, 0, buflen);
  77
  78         if (!data)
  79                 return ERROR_NOARG;
  80
  81         strings = ast_strdupa(data);
  82
  83         for (ptrkey = strings; *ptrkey; ptrkey++) {
  84                 if (*ptrkey == '|')
  85                         count++;
  86         }
  87
  88         sortable_keys = alloca(count * sizeof(struct sortable_keys));
  89
  90         memset(sortable_keys, 0, count * sizeof(struct sortable_keys));
  91
  92         /* Parse each into a struct */
  93         count2 = 0;
  94         while ((ptrkey = strsep(&strings, "|"))) {
  95                 ptrvalue = index(ptrkey, ':');
  96                 if (!ptrvalue) {
  97                         count--;
  98                         continue;
  99                 }
 100                 *ptrvalue++ = '\0';
 101                 sortable_keys[count2].key = ptrkey;
 102                 sscanf(ptrvalue, "%f", &sortable_keys[count2].value);
 103                 count2++;
 104         }
 105
 106         /* Sort the structs */
 107         qsort(sortable_keys, count, sizeof(struct sortable_keys), sort_subroutine);
 108
 109         for (count2 = 0; count2 < count; count2++) {
 110                 int blen = strlen(buffer);
 111                 if (element_count++) {
 112                         strncat(buffer + blen, ",", buflen - blen - 1);
 113                         blen++;
 114                 }
 115                 strncat(buffer + blen, sortable_keys[count2].key, buflen - blen - 1);
 116         }
 117
 118         return 0;
 119 }
 120
 121 static int cut_internal(struct ast_channel *chan, char *data, char *buffer, size_t buflen)
 122 {
 123         char *parse;
 124         AST_DECLARE_APP_ARGS(args,
 125                 AST_APP_ARG(varname);
 126                 AST_APP_ARG(delimiter);
 127                 AST_APP_ARG(field);
 128         );
 129
 130         memset(buffer, 0, buflen);
 131
 132         parse = ast_strdupa(data);
 133
 134         AST_STANDARD_APP_ARGS(args, parse);
 135
 136         /* Check and parse arguments */
 137         if(args.argc < 3){
 138                 return ERROR_NOARG;
 139         } else {
 140                 char d, ds[2];
 141                 char *tmp = alloca(strlen(args.varname) + 4);
 142                 char varvalue[MAXRESULT], *tmp2=varvalue;
 143
 144                 if (tmp) {
 145                         snprintf(tmp, strlen(args.varname) + 4, "${%s}", args.varname);
 146                         memset(varvalue, 0, sizeof(varvalue));
 147                 } else {
 148                         return ERROR_NOMEM;
 149                 }
 150
 151                 d = args.delimiter[0] ? args.delimiter[0] : '-';
 152
 153                 /* String form of the delimiter, for use with strsep(3) */
 154                 snprintf(ds, sizeof(ds), "%c", d);
 155
 156                 pbx_substitute_variables_helper(chan, tmp, tmp2, MAXRESULT - 1);
 157
 158                 if (tmp2) {
 159                         int curfieldnum = 1;
 160                         while (tmp2 != NULL && args.field != NULL) {
 161                                 char *nextgroup = strsep(&(args.field), "&");
 162                                 int num1 = 0, num2 = MAXRESULT;
 163                                 char trashchar;
 164
 165                                 if (sscanf(nextgroup, "%d-%d", &num1, &num2) == 2) {
 166                                         /* range with both start and end */
 167                                 } else if (sscanf(nextgroup, "-%d", &num2) == 1) {
 168                                         /* range with end */
 169                                         num1 = 0;
 170                                 } else if ((sscanf(nextgroup, "%d%c", &num1, &trashchar) == 2) && (trashchar == '-')) {
 171                                         /* range with start */
 172                                         num2 = MAXRESULT;
 173                                 } else if (sscanf(nextgroup, "%d", &num1) == 1) {
 174                                         /* single number */
 175                                         num2 = num1;
 176                                 } else {
 177                                         return ERROR_USAGE;
 178                                 }
 179
 180                                 /* Get to start, if any */
 181                                 if (num1 > 0) {
 182                                         while (tmp2 != (char *)NULL + 1 && curfieldnum < num1) {
 183                                                 tmp2 = index(tmp2, d) + 1;
 184                                                 curfieldnum++;
 185                                         }
 186                                 }
 187
 188                                 /* Most frequent problem is the expectation of reordering fields */
 189                                 if ((num1 > 0) && (curfieldnum > num1))
 190                                         ast_log(LOG_WARNING, "We're already past the field you wanted?\n");
 191
 192                                 /* Re-null tmp2 if we added 1 to NULL */
 193                                 if (tmp2 == (char *)NULL + 1)
 194                                         tmp2 = NULL;
 195
 196                                 /* Output fields until we either run out of fields or num2 is reached */
 197                                 while (tmp2 != NULL && curfieldnum <= num2) {
 198                                         char *tmp3 = strsep(&tmp2, ds);
 199                                         int curlen = strlen(buffer);
 200
 201                                         if (curlen)
 202                                                 snprintf(buffer + curlen, buflen - curlen, "%c%s", d, tmp3);
 203                                         else
 204                                                 snprintf(buffer, buflen, "%s", tmp3);
 205
 206                                         curfieldnum++;
 207                                 }
 208                         }
 209                 }
 210         }
 211         return 0;
 212 }
 213
 214 static int acf_sort_exec(struct ast_channel *chan, char *cmd, char *data, char *buf, size_t len)
 215 {
 216         struct localuser *u;
 217         int ret = -1;
 218
 219         LOCAL_USER_ADD(u);
 220
 221         switch (sort_internal(chan, data, buf, len)) {
 222         case ERROR_NOARG:
 223                 ast_log(LOG_ERROR, "SORT() requires an argument\n");
 224                 break;
 225         case ERROR_NOMEM:
 226                 ast_log(LOG_ERROR, "Out of memory\n");
 227                 break;
 228         case 0:
 229                 ret = 0;
 230                 break;
 231         default:
 232                 ast_log(LOG_ERROR, "Unknown internal error\n");
 233         }
 234         LOCAL_USER_REMOVE(u);
 235
 236         return ret;
 237 }
 238
 239 static int acf_cut_exec(struct ast_channel *chan, char *cmd, char *data, char *buf, size_t len)
 240 {
 241         int ret = -1;
 242         struct localuser *u;
 243
 244         LOCAL_USER_ADD(u);
 245
 246         switch (cut_internal(chan, data, buf, len)) {
 247         case ERROR_NOARG:
 248                 ast_log(LOG_ERROR, "Syntax: CUT(<varname>,<char-delim>,<range-spec>) - missing argument!\n");
 249                 break;
 250         case ERROR_NOMEM:
 251                 ast_log(LOG_ERROR, "Out of memory\n");
 252                 break;
 253         case ERROR_USAGE:
 254                 ast_log(LOG_ERROR, "Usage: CUT(<varname>,<char-delim>,<range-spec>)\n");
 255                 break;
 256         case 0:
 257                 ret = 0;
 258                 break;
 259         default:
 260                 ast_log(LOG_ERROR, "Unknown internal error\n");
 261         }
 262         LOCAL_USER_REMOVE(u);
 263
 264         return ret;
 265 }
 266
 267 struct ast_custom_function acf_sort = {
 268         .name = "SORT",
 269         .synopsis = "Sorts a list of key/vals into a list of keys, based upon the vals",
 270         .syntax = "SORT(key1:val1[...][,keyN:valN])",
 271         .desc =
 272 "Takes a comma-separated list of keys and values, each separated by a colon, and returns a\n"
 273 "comma-separated list of the keys, sorted by their values.  Values will be evaluated as\n"
 274 "floating-point numbers.\n",
 275         .read = acf_sort_exec,
 276 };
 277
 278 struct ast_custom_function acf_cut = {
 279         .name = "CUT",
 280         .synopsis = "Slices and dices strings, based upon a named delimiter.",
 281         .syntax = "CUT(<varname>,<char-delim>,<range-spec>)",
 282         .desc =
 283 "  varname    - variable you want cut\n"
 284 "  char-delim - defaults to '-'\n"
 285 "  range-spec - number of the field you want (1-based offset)\n"
 286 "             may also be specified as a range (with -)\n"
 287 "             or group of ranges and fields (with &)\n",
 288         .read = acf_cut_exec,
 289 };
 290
 291 static int unload_module(void *mod)
 292 {
 293         int res = 0;
 294
 295         res |= ast_custom_function_unregister(&acf_cut);
 296         res |= ast_custom_function_unregister(&acf_sort);
 297
 298         STANDARD_HANGUP_LOCALUSERS;
 299
 300         return res;
 301 }
 302
 303 static int load_module(void *mod)
 304 {
 305         int res = 0;
 306
 307         res |= ast_custom_function_register(&acf_cut);
 308         res |= ast_custom_function_register(&acf_sort);
 309
 310         return res;
 311 }
 312
 313 static const char *description(void)
 314 {
 315         return "Cut out information from a string";
 316 }
 317
 318 static const char *key(void)
 319 {
 320         return ASTERISK_GPL_KEY;
 321 }
 322
 323 STD_MOD(MOD_1, NULL, NULL, NULL);