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 struct sortable_keys {
  48         char *key;
  49         float value;
  50 };
  51
  52 static int sort_subroutine(const void *arg1, const void *arg2)
  53 {
  54         const struct sortable_keys *one=arg1, *two=arg2;
  55         if (one->value < two->value)
  56                 return -1;
  57         else if (one->value == two->value)
  58                 return 0;
  59         else
  60                 return 1;
  61 }
  62
  63 #define ERROR_NOARG     (-1)
  64 #define ERROR_NOMEM     (-2)
  65 #define ERROR_USAGE     (-3)
  66
  67 static int sort_internal(struct ast_channel *chan, char *data, char *buffer, size_t buflen)
  68 {
  69         char *strings, *ptrkey, *ptrvalue;
  70         int count=1, count2, element_count=0;
  71         struct sortable_keys *sortable_keys;
  72
  73         memset(buffer, 0, buflen);
  74
  75         if (!data)
  76                 return ERROR_NOARG;
  77
  78         strings = ast_strdupa(data);
  79
  80         for (ptrkey = strings; *ptrkey; ptrkey++) {
  81                 if (*ptrkey == '|')
  82                         count++;
  83         }
  84
  85         sortable_keys = alloca(count * sizeof(struct sortable_keys));
  86
  87         memset(sortable_keys, 0, count * sizeof(struct sortable_keys));
  88
  89         /* Parse each into a struct */
  90         count2 = 0;
  91         while ((ptrkey = strsep(&strings, "|"))) {
  92                 ptrvalue = index(ptrkey, ':');
  93                 if (!ptrvalue) {
  94                         count--;
  95                         continue;
  96                 }
  97                 *ptrvalue++ = '\0';
  98                 sortable_keys[count2].key = ptrkey;
  99                 sscanf(ptrvalue, "%f", &sortable_keys[count2].value);
 100                 count2++;
 101         }
 102
 103         /* Sort the structs */
 104         qsort(sortable_keys, count, sizeof(struct sortable_keys), sort_subroutine);
 105
 106         for (count2 = 0; count2 < count; count2++) {
 107                 int blen = strlen(buffer);
 108                 if (element_count++) {
 109                         strncat(buffer + blen, ",", buflen - blen - 1);
 110                         blen++;
 111                 }
 112                 strncat(buffer + blen, sortable_keys[count2].key, buflen - blen - 1);
 113         }
 114
 115         return 0;
 116 }
 117
 118 static int cut_internal(struct ast_channel *chan, char *data, char *buffer, size_t buflen)
 119 {
 120         char *parse;
 121         AST_DECLARE_APP_ARGS(args,
 122                 AST_APP_ARG(varname);
 123                 AST_APP_ARG(delimiter);
 124                 AST_APP_ARG(field);
 125         );
 126
 127         memset(buffer, 0, buflen);
 128
 129         parse = ast_strdupa(data);
 130
 131         AST_STANDARD_APP_ARGS(args, parse);
 132
 133         /* Check and parse arguments */
 134         if(args.argc < 3){
 135                 return ERROR_NOARG;
 136         } else {
 137                 char d, ds[2];
 138                 char *tmp = alloca(strlen(args.varname) + 4);
 139                 char varvalue[MAXRESULT], *tmp2=varvalue;
 140
 141                 if (tmp) {
 142                         snprintf(tmp, strlen(args.varname) + 4, "${%s}", args.varname);
 143                         memset(varvalue, 0, sizeof(varvalue));
 144                 } else {
 145                         return ERROR_NOMEM;
 146                 }
 147
 148                 if (args.delimiter[0] == '\\') {
 149                         if (args.delimiter[1] == 'n')
 150                                 d = '\n';
 151                         else if (args.delimiter[1] == 't')
 152                                 d = '\t';
 153                         else if (args.delimiter[1] == 'r')
 154                                 d = '\r';
 155                         else if (args.delimiter[1])
 156                                 d = args.delimiter[1];
 157                         else
 158                                 d = '-';
 159                 } else if (args.delimiter[0])
 160                         d = args.delimiter[0];
 161                 else
 162                         d = '-';
 163
 164                 /* String form of the delimiter, for use with strsep(3) */
 165                 snprintf(ds, sizeof(ds), "%c", d);
 166
 167                 pbx_substitute_variables_helper(chan, tmp, tmp2, MAXRESULT - 1);
 168
 169                 if (tmp2) {
 170                         int curfieldnum = 1;
 171                         while (tmp2 != NULL && args.field != NULL) {
 172                                 char *nextgroup = strsep(&(args.field), "&");
 173                                 int num1 = 0, num2 = MAXRESULT;
 174                                 char trashchar;
 175
 176                                 if (sscanf(nextgroup, "%d-%d", &num1, &num2) == 2) {
 177                                         /* range with both start and end */
 178                                 } else if (sscanf(nextgroup, "-%d", &num2) == 1) {
 179                                         /* range with end */
 180                                         num1 = 0;
 181                                 } else if ((sscanf(nextgroup, "%d%c", &num1, &trashchar) == 2) && (trashchar == '-')) {
 182                                         /* range with start */
 183                                         num2 = MAXRESULT;
 184                                 } else if (sscanf(nextgroup, "%d", &num1) == 1) {
 185                                         /* single number */
 186                                         num2 = num1;
 187                                 } else {
 188                                         return ERROR_USAGE;
 189                                 }
 190
 191                                 /* Get to start, if any */
 192                                 if (num1 > 0) {
 193                                         while (tmp2 != (char *)NULL + 1 && curfieldnum < num1) {
 194                                                 tmp2 = index(tmp2, d) + 1;
 195                                                 curfieldnum++;
 196                                         }
 197                                 }
 198
 199                                 /* Most frequent problem is the expectation of reordering fields */
 200                                 if ((num1 > 0) && (curfieldnum > num1))
 201                                         ast_log(LOG_WARNING, "We're already past the field you wanted?\n");
 202
 203                                 /* Re-null tmp2 if we added 1 to NULL */
 204                                 if (tmp2 == (char *)NULL + 1)
 205                                         tmp2 = NULL;
 206
 207                                 /* Output fields until we either run out of fields or num2 is reached */
 208                                 while (tmp2 != NULL && curfieldnum <= num2) {
 209                                         char *tmp3 = strsep(&tmp2, ds);
 210                                         int curlen = strlen(buffer);
 211
 212                                         if (curlen)
 213                                                 snprintf(buffer + curlen, buflen - curlen, "%c%s", d, tmp3);
 214                                         else
 215                                                 snprintf(buffer, buflen, "%s", tmp3);
 216
 217                                         curfieldnum++;
 218                                 }
 219                         }
 220                 }
 221         }
 222         return 0;
 223 }
 224
 225 static int acf_sort_exec(struct ast_channel *chan, char *cmd, char *data, char *buf, size_t len)
 226 {
 227         struct ast_module_user *u;
 228         int ret = -1;
 229
 230         u = ast_module_user_add(chan);
 231
 232         switch (sort_internal(chan, data, buf, len)) {
 233         case ERROR_NOARG:
 234                 ast_log(LOG_ERROR, "SORT() requires an argument\n");
 235                 break;
 236         case ERROR_NOMEM:
 237                 ast_log(LOG_ERROR, "Out of memory\n");
 238                 break;
 239         case 0:
 240                 ret = 0;
 241                 break;
 242         default:
 243                 ast_log(LOG_ERROR, "Unknown internal error\n");
 244         }
 245
 246         ast_module_user_remove(u);
 247
 248         return ret;
 249 }
 250
 251 static int acf_cut_exec(struct ast_channel *chan, char *cmd, char *data, char *buf, size_t len)
 252 {
 253         int ret = -1;
 254         struct ast_module_user *u = NULL;
 255
 256         if (chan) {
 257                 ast_autoservice_start(chan);
 258                 u = ast_module_user_add(chan);
 259         }
 260
 261         switch (cut_internal(chan, data, buf, len)) {
 262         case ERROR_NOARG:
 263                 ast_log(LOG_ERROR, "Syntax: CUT(<varname>,<char-delim>,<range-spec>) - missing argument!\n");
 264                 break;
 265         case ERROR_NOMEM:
 266                 ast_log(LOG_ERROR, "Out of memory\n");
 267                 break;
 268         case ERROR_USAGE:
 269                 ast_log(LOG_ERROR, "Usage: CUT(<varname>,<char-delim>,<range-spec>)\n");
 270                 break;
 271         case 0:
 272                 ret = 0;
 273                 break;
 274         default:
 275                 ast_log(LOG_ERROR, "Unknown internal error\n");
 276         }
 277
 278         if (chan) {
 279                 ast_module_user_remove(u);
 280                 ast_autoservice_stop(chan);
 281         }
 282
 283         return ret;
 284 }
 285
 286 struct ast_custom_function acf_sort = {
 287         .name = "SORT",
 288         .synopsis = "Sorts a list of key/vals into a list of keys, based upon the vals",
 289         .syntax = "SORT(key1:val1[...][,keyN:valN])",
 290         .desc =
 291 "Takes a comma-separated list of keys and values, each separated by a colon, and returns a\n"
 292 "comma-separated list of the keys, sorted by their values.  Values will be evaluated as\n"
 293 "floating-point numbers.\n",
 294         .read = acf_sort_exec,
 295 };
 296
 297 struct ast_custom_function acf_cut = {
 298         .name = "CUT",
 299         .synopsis = "Slices and dices strings, based upon a named delimiter.",
 300         .syntax = "CUT(<varname>,<char-delim>,<range-spec>)",
 301         .desc =
 302 "  varname    - variable you want cut\n"
 303 "  char-delim - defaults to '-'\n"
 304 "  range-spec - number of the field you want (1-based offset)\n"
 305 "             may also be specified as a range (with -)\n"
 306 "             or group of ranges and fields (with &)\n",
 307         .read = acf_cut_exec,
 308 };
 309
 310 static int unload_module(void)
 311 {
 312         int res = 0;
 313
 314         res |= ast_custom_function_unregister(&acf_cut);
 315         res |= ast_custom_function_unregister(&acf_sort);
 316
 317         ast_module_user_hangup_all();
 318
 319         return res;
 320 }
 321
 322 static int load_module(void)
 323 {
 324         int res = 0;
 325
 326         res |= ast_custom_function_register(&acf_cut);
 327         res |= ast_custom_function_register(&acf_sort);
 328
 329         return res;
 330 }
 331
 332 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Cut out information from a string");