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                 d = args.delimiter[0] ? args.delimiter[0] : '-';
 149
 150                 /* String form of the delimiter, for use with strsep(3) */
 151                 snprintf(ds, sizeof(ds), "%c", d);
 152
 153                 pbx_substitute_variables_helper(chan, tmp, tmp2, MAXRESULT - 1);
 154
 155                 if (tmp2) {
 156                         int curfieldnum = 1;
 157                         while (tmp2 != NULL && args.field != NULL) {
 158                                 char *nextgroup = strsep(&(args.field), "&");
 159                                 int num1 = 0, num2 = MAXRESULT;
 160                                 char trashchar;
 161
 162                                 if (sscanf(nextgroup, "%d-%d", &num1, &num2) == 2) {
 163                                         /* range with both start and end */
 164                                 } else if (sscanf(nextgroup, "-%d", &num2) == 1) {
 165                                         /* range with end */
 166                                         num1 = 0;
 167                                 } else if ((sscanf(nextgroup, "%d%c", &num1, &trashchar) == 2) && (trashchar == '-')) {
 168                                         /* range with start */
 169                                         num2 = MAXRESULT;
 170                                 } else if (sscanf(nextgroup, "%d", &num1) == 1) {
 171                                         /* single number */
 172                                         num2 = num1;
 173                                 } else {
 174                                         return ERROR_USAGE;
 175                                 }
 176
 177                                 /* Get to start, if any */
 178                                 if (num1 > 0) {
 179                                         while (tmp2 != (char *)NULL + 1 && curfieldnum < num1) {
 180                                                 tmp2 = index(tmp2, d) + 1;
 181                                                 curfieldnum++;
 182                                         }
 183                                 }
 184
 185                                 /* Most frequent problem is the expectation of reordering fields */
 186                                 if ((num1 > 0) && (curfieldnum > num1))
 187                                         ast_log(LOG_WARNING, "We're already past the field you wanted?\n");
 188
 189                                 /* Re-null tmp2 if we added 1 to NULL */
 190                                 if (tmp2 == (char *)NULL + 1)
 191                                         tmp2 = NULL;
 192
 193                                 /* Output fields until we either run out of fields or num2 is reached */
 194                                 while (tmp2 != NULL && curfieldnum <= num2) {
 195                                         char *tmp3 = strsep(&tmp2, ds);
 196                                         int curlen = strlen(buffer);
 197
 198                                         if (curlen)
 199                                                 snprintf(buffer + curlen, buflen - curlen, "%c%s", d, tmp3);
 200                                         else
 201                                                 snprintf(buffer, buflen, "%s", tmp3);
 202
 203                                         curfieldnum++;
 204                                 }
 205                         }
 206                 }
 207         }
 208         return 0;
 209 }
 210
 211 static int acf_sort_exec(struct ast_channel *chan, char *cmd, char *data, char *buf, size_t len)
 212 {
 213         struct ast_module_user *u;
 214         int ret = -1;
 215
 216         u = ast_module_user_add(chan);
 217
 218         switch (sort_internal(chan, data, buf, len)) {
 219         case ERROR_NOARG:
 220                 ast_log(LOG_ERROR, "SORT() requires an argument\n");
 221                 break;
 222         case ERROR_NOMEM:
 223                 ast_log(LOG_ERROR, "Out of memory\n");
 224                 break;
 225         case 0:
 226                 ret = 0;
 227                 break;
 228         default:
 229                 ast_log(LOG_ERROR, "Unknown internal error\n");
 230         }
 231
 232         ast_module_user_remove(u);
 233
 234         return ret;
 235 }
 236
 237 static int acf_cut_exec(struct ast_channel *chan, char *cmd, char *data, char *buf, size_t len)
 238 {
 239         int ret = -1;
 240         struct ast_module_user *u;
 241
 242         u = ast_module_user_add(chan);
 243
 244         switch (cut_internal(chan, data, buf, len)) {
 245         case ERROR_NOARG:
 246                 ast_log(LOG_ERROR, "Syntax: CUT(<varname>,<char-delim>,<range-spec>) - missing argument!\n");
 247                 break;
 248         case ERROR_NOMEM:
 249                 ast_log(LOG_ERROR, "Out of memory\n");
 250                 break;
 251         case ERROR_USAGE:
 252                 ast_log(LOG_ERROR, "Usage: CUT(<varname>,<char-delim>,<range-spec>)\n");
 253                 break;
 254         case 0:
 255                 ret = 0;
 256                 break;
 257         default:
 258                 ast_log(LOG_ERROR, "Unknown internal error\n");
 259         }
 260
 261         ast_module_user_remove(u);
 262
 263         return ret;
 264 }
 265
 266 struct ast_custom_function acf_sort = {
 267         .name = "SORT",
 268         .synopsis = "Sorts a list of key/vals into a list of keys, based upon the vals",
 269         .syntax = "SORT(key1:val1[...][,keyN:valN])",
 270         .desc =
 271 "Takes a comma-separated list of keys and values, each separated by a colon, and returns a\n"
 272 "comma-separated list of the keys, sorted by their values.  Values will be evaluated as\n"
 273 "floating-point numbers.\n",
 274         .read = acf_sort_exec,
 275 };
 276
 277 struct ast_custom_function acf_cut = {
 278         .name = "CUT",
 279         .synopsis = "Slices and dices strings, based upon a named delimiter.",
 280         .syntax = "CUT(<varname>,<char-delim>,<range-spec>)",
 281         .desc =
 282 "  varname    - variable you want cut\n"
 283 "  char-delim - defaults to '-'\n"
 284 "  range-spec - number of the field you want (1-based offset)\n"
 285 "             may also be specified as a range (with -)\n"
 286 "             or group of ranges and fields (with &)\n",
 287         .read = acf_cut_exec,
 288 };
 289
 290 static int unload_module(void)
 291 {
 292         int res = 0;
 293
 294         res |= ast_custom_function_unregister(&acf_cut);
 295         res |= ast_custom_function_unregister(&acf_sort);
 296
 297         ast_module_user_hangup_all();
 298
 299         return res;
 300 }
 301
 302 static int load_module(void)
 303 {
 304         int res = 0;
 305
 306         res |= ast_custom_function_register(&acf_cut);
 307         res |= ast_custom_function_register(&acf_sort);
 308
 309         return res;
 310 }
 311
 312 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Cut out information from a string");