/* * Asterisk -- An open source telephony toolkit. * * Copyright (C) 2004 - 2006, Andy Powell * * Updated by Mark Spencer <markster@digium.com> * Updated by Nir Simionovich <nirs@greenfieldtech.net> * Updated by Naveen Albert <asterisk@phreaknet.org> * * See http://www.asterisk.org for more information about * the Asterisk project. Please do not directly contact * any of the maintainers of this project for assistance; * the project provides a web site, mailing lists and IRC * channels for your use. * * This program is free software, distributed under the terms of * the GNU General Public License Version 2. See the LICENSE file * at the top of the source tree. */ /*! \file * * \brief Math related dialplan function * * \author Andy Powell * \author Mark Spencer <markster@digium.com> * \author Nir Simionovich <nirs@greenfieldtech.net> * \author Naveen Albert <asterisk@phreaknet.org> * * \ingroup functions */ /*** MODULEINFO <support_level>core</support_level> ***/ #include "asterisk.h" #include <math.h> #include "asterisk/module.h" #include "asterisk/channel.h" #include "asterisk/pbx.h" #include "asterisk/utils.h" #include "asterisk/conversions.h" #include "asterisk/app.h" #include "asterisk/config.h" #include "asterisk/test.h" /*** DOCUMENTATION <function name="MATH" language="en_US"> <since> <version>1.2.0</version> </since> <synopsis> Performs Mathematical Functions. </synopsis> <syntax> <parameter name="expression" required="true"> <para>Is of the form: <replaceable>number1</replaceable><replaceable>op</replaceable><replaceable>number2</replaceable> where the possible values for <replaceable>op</replaceable> are:</para> <para>+,-,/,*,%,<<,>>,^,AND,OR,XOR,<,>,<=,>=,== (and behave as their C equivalents)</para> </parameter> <parameter name="type"> <para>Wanted type of result:</para> <para>f, float - float(default)</para> <para>i, int - integer</para> <para>h, hex - hex</para> <para>c, char - char</para> </parameter> </syntax> <description> <para>Performs mathematical functions based on two parameters and an operator. The returned value type is <replaceable>type</replaceable></para> <example title="Sets var i to 11"> same => n,Set(i=${MATH(123%16,int)}) </example> </description> </function> <function name="INC" language="en_US"> <since> <version>1.8.0</version> </since> <synopsis> Increments the value of a variable, while returning the updated value to the dialplan </synopsis> <syntax> <parameter name="variable" required="true"> <para> The variable name to be manipulated, without the braces. </para> </parameter> </syntax> <description> <para>Increments the value of a variable, while returning the updated value to the dialplan</para> <para>Example: INC(MyVAR) - Increments MyVar</para> <para>Note: INC(${MyVAR}) - Is wrong, as INC expects the variable name, not its value</para> </description> </function> <function name="DEC" language="en_US"> <since> <version>1.8.0</version> </since> <synopsis> Decrements the value of a variable, while returning the updated value to the dialplan </synopsis> <syntax> <parameter name="variable" required="true"> <para> The variable name to be manipulated, without the braces. </para> </parameter> </syntax> <description> <para>Decrements the value of a variable, while returning the updated value to the dialplan</para> <example title="Decrements MyVAR"> same => n,NoOp(${DEC(MyVAR)}) </example> <note><para>DEC(${MyVAR}) is wrong, as DEC expects the variable name, not its value</para></note> </description> </function> <function name="MIN" language="en_US"> <since> <version>16.19.0</version> <version>18.5.0</version> </since> <synopsis> Returns the minimum of two numbers. </synopsis> <syntax> <parameter name="num1" /> <parameter name="num2" /> </syntax> <description> <para>Returns the minimum of two numbers <replaceable>num1</replaceable> and <replaceable>num2</replaceable>.</para> <example title="Sets the min variable equal to 4"> same => n,Set(min=${MIN(7,4)}) </example> </description> </function> <function name="MAX" language="en_US"> <since> <version>16.19.0</version> <version>18.5.0</version> </since> <synopsis> Returns the maximum of two numbers. </synopsis> <syntax> <parameter name="num1" /> <parameter name="num2" /> </syntax> <description> <para>Returns the maximum of two numbers <replaceable>num1</replaceable> and <replaceable>num2</replaceable>.</para> <example title="Sets the max variable equal to 13"> same => n,Set(max=${MAX(4,7)}) </example> </description> </function> <function name="ABS" language="en_US"> <since> <version>16.19.0</version> <version>18.5.0</version> </since> <synopsis> Returns absolute value of a number. </synopsis> <syntax> <parameter name="num" /> </syntax> <description> <para>Returns the absolute value of a number <replaceable>num</replaceable>.</para> <example title="Sets the absval variable equal to 13"> same => n,Set(absval=${ABS(-13)}) </example> </description> </function> ***/ 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 }; static int math(struct ast_channel *chan, const char *cmd, char *parse, char *buf, size_t len) { 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 crement_function_read(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t len) { 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 acf_min_exec(struct ast_channel *chan, const char *cmd, char *parse, char *buffer, size_t buflen) { double num1, num2, response_num = 0; AST_DECLARE_APP_ARGS(args, AST_APP_ARG(num1); AST_APP_ARG(num2); ); AST_STANDARD_APP_ARGS(args, parse); if (ast_strlen_zero(args.num1) && ast_strlen_zero(args.num2)) { ast_log(LOG_ERROR, "Missing argument for number(s)."); return -1; } if (ast_strlen_zero(args.num1)) { response_num = -1; /* couldn't read num1 successfully */ } else if (sscanf(args.num1, "%30lf", &num1) != 1) { ast_log(LOG_WARNING, "'%s' is not a valid number\n", args.num1); return -1; } if (ast_strlen_zero(args.num2)) { num2 = num1; /* num1 must be a valid integer here */ } else if (sscanf(args.num2, "%30lf", &num2) != 1) { ast_log(LOG_WARNING, "'%s' is not a valid number\n", args.num2); return -1; } if (response_num == -1) { /* could only read num2 */ response_num = num2; } else { response_num = (num1 > num2) ? num2 : num1; } ast_debug(1, "%f is the minimum of [%f,%f]\n", response_num, num1, num2); if ((int) response_num == response_num) { snprintf(buffer, buflen, "%d", (int) response_num); } else { snprintf(buffer, buflen, "%f", response_num); } return 0; } static int acf_max_exec(struct ast_channel *chan, const char *cmd, char *parse, char *buffer, size_t buflen) { double num1, num2, response_num = 0; AST_DECLARE_APP_ARGS(args, AST_APP_ARG(num1); AST_APP_ARG(num2); ); AST_STANDARD_APP_ARGS(args, parse); if (ast_strlen_zero(args.num1) && ast_strlen_zero(args.num2)) { ast_log(LOG_ERROR, "Missing argument for number(s)."); return -1; } if (ast_strlen_zero(args.num1)) { response_num = -1; /* couldn't read num1 successfully */ } else if (sscanf(args.num1, "%30lf", &num1) != 1) { ast_log(LOG_WARNING, "'%s' is not a valid number\n", args.num1); return -1; } if (ast_strlen_zero(args.num2)) { num2 = num1; /* num1 must be a valid integer here */ } else if (sscanf(args.num2, "%30lf", &num2) != 1) { ast_log(LOG_WARNING, "'%s' is not a valid number\n", args.num2); return -1; } if (response_num == -1) { /* could only read num2 */ response_num = num2; } else { response_num = (num1 < num2) ? num2 : num1; } ast_debug(1, "%f is the maximum of [%f,%f]\n", response_num, num1, num2); if ((int) response_num == response_num) { snprintf(buffer, buflen, "%d", (int) response_num); } else { snprintf(buffer, buflen, "%f", response_num); } return 0; } static int acf_abs_exec(struct ast_channel *chan, const char *cmd, char *parse, char *buffer, size_t buflen) { double num1, response_num; AST_DECLARE_APP_ARGS(args, AST_APP_ARG(num1); ); AST_STANDARD_APP_ARGS(args, parse); if (ast_strlen_zero(args.num1) || sscanf(args.num1, "%30lf", &num1) != 1) { ast_log(LOG_WARNING, "Bad or missing argument for number: %s", args.num1); return -1; } response_num = fabs(num1); ast_debug(1, "%f is the absolute value of %f\n", response_num, num1); if ((int) response_num == response_num) { snprintf(buffer, buflen, "%d", (int) response_num); } else { snprintf(buffer, buflen, "%f", response_num); } return 0; } static struct ast_custom_function math_function = { .name = "MATH", .read = math }; static struct ast_custom_function increment_function = { .name = "INC", .read = crement_function_read, }; static struct ast_custom_function decrement_function = { .name = "DEC", .read = crement_function_read, }; static struct ast_custom_function acf_min = { .name = "MIN", .read = acf_min_exec, .read_max = 12, }; static struct ast_custom_function acf_max = { .name = "MAX", .read = acf_max_exec, .read_max = 12, }; static struct ast_custom_function acf_abs = { .name = "ABS", .read = acf_abs_exec, .read_max = 12, }; #ifdef TEST_FRAMEWORK AST_TEST_DEFINE(test_MATH_function) { enum ast_test_result_state res = AST_TEST_PASS; struct ast_str *expr, *result; switch (cmd) { case TEST_INIT: info->name = "test_MATH_function"; info->category = "/main/pbx/"; info->summary = "Test MATH function substitution"; info->description = "Executes a series of variable substitutions using the MATH function and ensures that the expected results are received."; return AST_TEST_NOT_RUN; case TEST_EXECUTE: break; } ast_test_status_update(test, "Testing MATH() substitution ...\n"); if (!(expr = ast_str_create(16))) { return AST_TEST_FAIL; } if (!(result = ast_str_create(16))) { ast_free(expr); return AST_TEST_FAIL; } ast_str_set(&expr, 0, "${MATH(170 AND 63,i)}"); ast_str_substitute_variables(&result, 0, NULL, ast_str_buffer(expr)); if (strcmp(ast_str_buffer(result), "42") != 0) { ast_test_status_update(test, "Expected result '42' not returned! ('%s')\n", ast_str_buffer(result)); res = AST_TEST_FAIL; } ast_str_set(&expr, 0, "${MATH(170AND63,i)}"); ast_str_substitute_variables(&result, 0, NULL, ast_str_buffer(expr)); if (strcmp(ast_str_buffer(result), "42") != 0) { ast_test_status_update(test, "Expected result '42' not returned! ('%s')\n", ast_str_buffer(result)); res = AST_TEST_FAIL; } ast_free(expr); ast_free(result); return res; } #endif static int unload_module(void) { int res = 0; res |= ast_custom_function_unregister(&math_function); res |= ast_custom_function_unregister(&increment_function); res |= ast_custom_function_unregister(&decrement_function); res |= ast_custom_function_unregister(&acf_min); res |= ast_custom_function_unregister(&acf_max); res |= ast_custom_function_unregister(&acf_abs); AST_TEST_UNREGISTER(test_MATH_function); return res; } static int load_module(void) { int res = 0; res |= ast_custom_function_register(&math_function); res |= ast_custom_function_register(&increment_function); res |= ast_custom_function_register(&decrement_function); res |= ast_custom_function_register(&acf_min); res |= ast_custom_function_register(&acf_max); res |= ast_custom_function_register(&acf_abs); AST_TEST_REGISTER(test_MATH_function); return res; } AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Mathematical dialplan function");