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