Sat Apr 26 2014 22:02:51

Asterisk developer's documentation

Enumerations | Functions | Variables
func_math.c File Reference
Module: Dial plan functions

Math related dialplan function. More...

#include "asterisk.h"
#include <math.h>
#include "asterisk/module.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/utils.h"
#include "asterisk/app.h"
#include "asterisk/config.h"
#include "asterisk/test.h"
Include dependency graph for func_math.c:

Go to the source code of this file.

Enumerations

enum  TypeOfFunctions {
  ADDFUNCTION, DIVIDEFUNCTION, MULTIPLYFUNCTION, SUBTRACTFUNCTION,
  MODULUSFUNCTION, POWFUNCTION, SHLEFTFUNCTION, SHRIGHTFUNCTION,
  BITWISEANDFUNCTION, BITWISEXORFUNCTION, BITWISEORFUNCTION, GTFUNCTION,
  LTFUNCTION, GTEFUNCTION, LTEFUNCTION, EQFUNCTION
}
enum  TypeOfResult { FLOAT_RESULT, INT_RESULT, HEX_RESULT, CHAR_RESULT }

Functions

static void __reg_module (void)
static void __unreg_module (void)
static int crement_function_read (struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t len)
static int load_module (void)
static int math (struct ast_channel *chan, const char *cmd, char *parse, char *buf, size_t len)
static int unload_module (void)

Variables

static struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "Mathematical dialplan function" , .key = "This paragraph is copyright (c) 2006 by Digium, Inc. \In order for your module to load, it must return this \key via a function called \"key\". Any code which \includes this paragraph must be licensed under the GNU \General Public License version 2 or later (at your \option). In addition to Digium's general reservations \of rights, Digium expressly reserves the right to \allow other parties to license this paragraph under \different terms. Any use of Digium, Inc. trademarks or \logos (including \"Asterisk\" or \"Digium\") without \express written permission of Digium, Inc. is prohibited.\n" , .buildopt_sum = AST_BUILDOPT_SUM, .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_DEFAULT, }
static struct ast_module_info * ast_module_info = &__mod_info
static struct ast_custom_function decrement_function
static struct ast_custom_function increment_function
static struct ast_custom_function math_function

Detailed Description

Math related dialplan function.

Author:
Andy Powell
Mark Spencer <markster@digium.com>
Nir Simionovich <nirs@greenfieldtech.net>

Definition in file func_math.c.

Enumeration Type Documentation

enum TypeOfFunctions
Enumerator:
ADDFUNCTION 
DIVIDEFUNCTION 
MULTIPLYFUNCTION 
SUBTRACTFUNCTION 
MODULUSFUNCTION 
POWFUNCTION 
SHLEFTFUNCTION 
SHRIGHTFUNCTION 
BITWISEANDFUNCTION 
BITWISEXORFUNCTION 
BITWISEORFUNCTION 
GTFUNCTION 
LTFUNCTION 
GTEFUNCTION 
LTEFUNCTION 
EQFUNCTION 

Definition at line 112 of file func_math.c.

                     {
   ADDFUNCTION,
   DIVIDEFUNCTION,
   MULTIPLYFUNCTION,
   SUBTRACTFUNCTION,
   MODULUSFUNCTION,
   POWFUNCTION,
   SHLEFTFUNCTION,
   SHRIGHTFUNCTION,
   BITWISEANDFUNCTION,
   BITWISEXORFUNCTION,
   BITWISEORFUNCTION,
   GTFUNCTION,
   LTFUNCTION,
   GTEFUNCTION,
   LTEFUNCTION,
   EQFUNCTION
};
enum TypeOfResult
Enumerator:
FLOAT_RESULT 
INT_RESULT 
HEX_RESULT 
CHAR_RESULT 

Definition at line 131 of file func_math.c.

                  {
   FLOAT_RESULT,
   INT_RESULT,
   HEX_RESULT,
   CHAR_RESULT
};

Function Documentation

static void __reg_module ( void  ) [static]

Definition at line 542 of file func_math.c.

static void __unreg_module ( void  ) [static]

Definition at line 542 of file func_math.c.

static int crement_function_read ( struct ast_channel *  chan,
const char *  cmd,
char *  data,
char *  buf,
size_t  len 
) [static]

Definition at line 381 of file func_math.c.

References ast_channel_lock, ast_channel_unlock, ast_copy_string(), ast_log(), ast_strlen_zero(), LOG_NOTICE, LOG_WARNING, pbx_builtin_getvar_helper(), pbx_builtin_setvar_helper(), and var.

{
   int ret = -1;
   int int_value = 0;
   int modify_orig = 0;
   const char *var;
   char endchar = 0, returnvar[12]; /* If you need a variable longer than 11 digits - something is way wrong */

   if (ast_strlen_zero(data)) {
      ast_log(LOG_WARNING, "Syntax: %s(<data>) - missing argument!\n", cmd);
      return -1;
   }

   if (!chan) {
      ast_log(LOG_WARNING, "No channel was provided to %s function.\n", cmd);
      return -1;
   }

   ast_channel_lock(chan);

   if (!(var = pbx_builtin_getvar_helper(chan, data))) {
      ast_log(LOG_NOTICE, "Failed to obtain variable %s, bailing out\n", data);
      ast_channel_unlock(chan);
      return -1;
   }

   if (ast_strlen_zero(var)) {
      ast_log(LOG_NOTICE, "Variable %s doesn't exist - are you sure you wrote it correctly?\n", data);
      ast_channel_unlock(chan);
      return -1;
   }

   if (sscanf(var, "%30d%1c", &int_value, &endchar) == 0 || endchar != 0) {
      ast_log(LOG_NOTICE, "The content of ${%s} is not a numeric value - bailing out!\n", data);
      ast_channel_unlock(chan);
      return -1;
   }

   /* now we'll actually do something useful */
   if (!strcasecmp(cmd, "INC")) {              /* Increment variable */
      int_value++;
      modify_orig = 1;
   } else if (!strcasecmp(cmd, "DEC")) {       /* Decrement variable */
      int_value--;
      modify_orig = 1;
   }

   if (snprintf(returnvar, sizeof(returnvar), "%d", int_value) > 0) {
      pbx_builtin_setvar_helper(chan, data, returnvar);
      if (modify_orig) {
         ast_copy_string(buf, returnvar, len);
      }
      ret = 0;
   } else {
      pbx_builtin_setvar_helper(chan, data, "0");
      if (modify_orig) {
         ast_copy_string(buf, "0", len);
      }
      ast_log(LOG_NOTICE, "Variable %s refused to be %sREMENTED, setting value to 0", data, cmd);
      ret = 0;
   }

   ast_channel_unlock(chan);

   return ret;
}
static int load_module ( void  ) [static]

Definition at line 530 of file func_math.c.

References ast_custom_function_register, and AST_TEST_REGISTER.

{
   int res = 0;

   res |= ast_custom_function_register(&math_function);
   res |= ast_custom_function_register(&increment_function);
   res |= ast_custom_function_register(&decrement_function);
   AST_TEST_REGISTER(test_MATH_function);

   return res;
}
static int math ( struct ast_channel *  chan,
const char *  cmd,
char *  parse,
char *  buf,
size_t  len 
) [static]

Definition at line 138 of file func_math.c.

References ADDFUNCTION, args, AST_APP_ARG, ast_copy_string(), AST_DECLARE_APP_ARGS, ast_log(), AST_STANDARD_APP_ARGS, ast_strlen_zero(), BITWISEANDFUNCTION, BITWISEORFUNCTION, BITWISEXORFUNCTION, CHAR_RESULT, DIVIDEFUNCTION, EQFUNCTION, FLOAT_RESULT, GTEFUNCTION, GTFUNCTION, HEX_RESULT, INT_RESULT, LOG_WARNING, LTEFUNCTION, LTFUNCTION, MODULUSFUNCTION, MULTIPLYFUNCTION, POWFUNCTION, SHLEFTFUNCTION, SHRIGHTFUNCTION, and SUBTRACTFUNCTION.

{
   double fnum1;
   double fnum2;
   double ftmp = 0;
   char *op;
   int iaction = -1;
   int type_of_result = FLOAT_RESULT;
   char *mvalue1, *mvalue2 = NULL, *mtype_of_result;
   int negvalue1 = 0;
   AST_DECLARE_APP_ARGS(args,
              AST_APP_ARG(argv0);
              AST_APP_ARG(argv1);
   );

   if (ast_strlen_zero(parse)) {
      ast_log(LOG_WARNING, "Syntax: MATH(<number1><op><number 2>[,<type_of_result>]) - missing argument!\n");
      return -1;
   }

   AST_STANDARD_APP_ARGS(args, parse);

   if (args.argc < 1) {
      ast_log(LOG_WARNING, "Syntax: MATH(<number1><op><number 2>[,<type_of_result>]) - missing argument!\n");
      return -1;
   }

   mvalue1 = args.argv0;

   if (mvalue1[0] == '-') {
      negvalue1 = 1;
      mvalue1++;
   }

   if ((op = strchr(mvalue1, '*'))) {
      iaction = MULTIPLYFUNCTION;
      *op = '\0';
   } else if ((op = strchr(mvalue1, '/'))) {
      iaction = DIVIDEFUNCTION;
      *op = '\0';
   } else if ((op = strchr(mvalue1, '%'))) {
      iaction = MODULUSFUNCTION;
      *op = '\0';
   } else if ((op = strchr(mvalue1, '^'))) {
      iaction = POWFUNCTION;
      *op = '\0';
   } else if ((op = strstr(mvalue1, "AND"))) {
      iaction = BITWISEANDFUNCTION;
      *op = '\0';
      op += 2;
   } else if ((op = strstr(mvalue1, "XOR"))) {
      iaction = BITWISEXORFUNCTION;
      *op = '\0';
      op += 2;
   } else if ((op = strstr(mvalue1, "OR"))) {
      iaction = BITWISEORFUNCTION;
      *op = '\0';
      ++op;
   } else if ((op = strchr(mvalue1, '>'))) {
      iaction = GTFUNCTION;
      *op = '\0';
      if (*(op + 1) == '=') {
         iaction = GTEFUNCTION;
         ++op;
      } else if (*(op + 1) == '>') {
         iaction = SHRIGHTFUNCTION;
         ++op;
      }
   } else if ((op = strchr(mvalue1, '<'))) {
      iaction = LTFUNCTION;
      *op = '\0';
      if (*(op + 1) == '=') {
         iaction = LTEFUNCTION;
         ++op;
      } else if (*(op + 1) == '<') {
         iaction = SHLEFTFUNCTION;
         ++op;
      }
   } else if ((op = strchr(mvalue1, '='))) {
      *op = '\0';
      if (*(op + 1) == '=') {
         iaction = EQFUNCTION;
         ++op;
      } else
         op = NULL;
   } else if ((op = strchr(mvalue1, '+'))) {
      iaction = ADDFUNCTION;
      *op = '\0';
   } else if ((op = strchr(mvalue1, '-'))) { /* subtraction MUST always be last, in case we have a negative second number */
      iaction = SUBTRACTFUNCTION;
      *op = '\0';
   }

   if (op)
      mvalue2 = op + 1;

   /* detect wanted type of result */
   mtype_of_result = args.argv1;
   if (mtype_of_result) {
      if (!strcasecmp(mtype_of_result, "float")
          || !strcasecmp(mtype_of_result, "f"))
         type_of_result = FLOAT_RESULT;
      else if (!strcasecmp(mtype_of_result, "int")
          || !strcasecmp(mtype_of_result, "i"))
         type_of_result = INT_RESULT;
      else if (!strcasecmp(mtype_of_result, "hex")
          || !strcasecmp(mtype_of_result, "h"))
         type_of_result = HEX_RESULT;
      else if (!strcasecmp(mtype_of_result, "char")
          || !strcasecmp(mtype_of_result, "c"))
         type_of_result = CHAR_RESULT;
      else {
         ast_log(LOG_WARNING, "Unknown type of result requested '%s'.\n",
               mtype_of_result);
         return -1;
      }
   }

   if (!mvalue2) {
      ast_log(LOG_WARNING,
            "Supply all the parameters - just this once, please\n");
      return -1;
   }

   if (sscanf(mvalue1, "%30lf", &fnum1) != 1) {
      ast_log(LOG_WARNING, "'%s' is not a valid number\n", mvalue1);
      return -1;
   }

   if (sscanf(mvalue2, "%30lf", &fnum2) != 1) {
      ast_log(LOG_WARNING, "'%s' is not a valid number\n", mvalue2);
      return -1;
   }

   if (negvalue1)
      fnum1 = 0 - fnum1;

   switch (iaction) {
   case ADDFUNCTION:
      ftmp = fnum1 + fnum2;
      break;
   case DIVIDEFUNCTION:
      if (fnum2 <= 0)
         ftmp = 0;         /* can't do a divide by 0 */
      else
         ftmp = (fnum1 / fnum2);
      break;
   case MULTIPLYFUNCTION:
      ftmp = (fnum1 * fnum2);
      break;
   case SUBTRACTFUNCTION:
      ftmp = (fnum1 - fnum2);
      break;
   case MODULUSFUNCTION:
      {
         int inum1 = fnum1;
         int inum2 = fnum2;

         if (inum2 == 0) {
            ftmp = 0;
         } else {
            ftmp = (inum1 % inum2);
         }

         break;
      }
   case POWFUNCTION:
      ftmp = pow(fnum1, fnum2);
      break;
   case SHLEFTFUNCTION:
      {
         int inum1 = fnum1;
         int inum2 = fnum2;

         ftmp = (inum1 << inum2);
         break;
      }
   case SHRIGHTFUNCTION:
      {
         int inum1 = fnum1;
         int inum2 = fnum2;

         ftmp = (inum1 >> inum2);
         break;
      }
   case BITWISEANDFUNCTION:
      {
         int inum1 = fnum1;
         int inum2 = fnum2;
         ftmp = (inum1 & inum2);
         break;
      }
   case BITWISEXORFUNCTION:
      {
         int inum1 = fnum1;
         int inum2 = fnum2;
         ftmp = (inum1 ^ inum2);
         break;
      }
   case BITWISEORFUNCTION:
      {
         int inum1 = fnum1;
         int inum2 = fnum2;
         ftmp = (inum1 | inum2);
         break;
      }
   case GTFUNCTION:
      ast_copy_string(buf, (fnum1 > fnum2) ? "TRUE" : "FALSE", len);
      break;
   case LTFUNCTION:
      ast_copy_string(buf, (fnum1 < fnum2) ? "TRUE" : "FALSE", len);
      break;
   case GTEFUNCTION:
      ast_copy_string(buf, (fnum1 >= fnum2) ? "TRUE" : "FALSE", len);
      break;
   case LTEFUNCTION:
      ast_copy_string(buf, (fnum1 <= fnum2) ? "TRUE" : "FALSE", len);
      break;
   case EQFUNCTION:
      ast_copy_string(buf, (fnum1 == fnum2) ? "TRUE" : "FALSE", len);
      break;
   default:
      ast_log(LOG_WARNING,
            "Something happened that neither of us should be proud of %d\n",
            iaction);
      return -1;
   }

   if (iaction < GTFUNCTION || iaction > EQFUNCTION) {
      if (type_of_result == FLOAT_RESULT)
         snprintf(buf, len, "%f", ftmp);
      else if (type_of_result == INT_RESULT)
         snprintf(buf, len, "%i", (int) ftmp);
      else if (type_of_result == HEX_RESULT)
         snprintf(buf, len, "%x", (unsigned int) ftmp);
      else if (type_of_result == CHAR_RESULT)
         snprintf(buf, len, "%c", (unsigned char) ftmp);
   }

   return 0;
}
static int unload_module ( void  ) [static]

Definition at line 518 of file func_math.c.

References ast_custom_function_unregister(), and AST_TEST_UNREGISTER.

{
   int res = 0;

   res |= ast_custom_function_unregister(&math_function);
   res |= ast_custom_function_unregister(&increment_function);
   res |= ast_custom_function_unregister(&decrement_function);
   AST_TEST_UNREGISTER(test_MATH_function);

   return res;
}

Variable Documentation

struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "Mathematical dialplan function" , .key = "This paragraph is copyright (c) 2006 by Digium, Inc. \In order for your module to load, it must return this \key via a function called \"key\". Any code which \includes this paragraph must be licensed under the GNU \General Public License version 2 or later (at your \option). In addition to Digium's general reservations \of rights, Digium expressly reserves the right to \allow other parties to license this paragraph under \different terms. Any use of Digium, Inc. trademarks or \logos (including \"Asterisk\" or \"Digium\") without \express written permission of Digium, Inc. is prohibited.\n" , .buildopt_sum = AST_BUILDOPT_SUM, .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_DEFAULT, } [static]

Definition at line 542 of file func_math.c.

struct ast_module_info* ast_module_info = &__mod_info [static]

Definition at line 542 of file func_math.c.

struct ast_custom_function decrement_function [static]
Initial value:
 {
   .name = "DEC",
   .read = crement_function_read,
}

Definition at line 460 of file func_math.c.

struct ast_custom_function increment_function [static]
Initial value:
 {
   .name = "INC",
   .read = crement_function_read,
}

Definition at line 455 of file func_math.c.

struct ast_custom_function math_function [static]
Initial value:
 {
   .name = "MATH",
   .read = math
}

Definition at line 450 of file func_math.c.