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  •  * Asterisk -- An open source telephony toolkit.
    
     *
     * Copyright (C) 2005, Digium, Inc.
    
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     * Portions Copyright (C) 2005, Tilghman Lesher.  All rights reserved.
     * Portions Copyright (C) 2005, Anthony Minessale II
    
     * 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.
     */
    
    
     * \brief String manipulation dialplan functions
    
     *
     * \author Tilghman Lesher
     * \author Anothony Minessale II 
    
    #include <stdio.h>
    
    #include <string.h>
    #include <sys/types.h>
    #include <regex.h>
    
    
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    #include "asterisk.h"
    
    /* ASTERISK_FILE_VERSION(__FILE__, "$Revision$") */
    
    
    #include "asterisk/channel.h"
    #include "asterisk/pbx.h"
    #include "asterisk/logger.h"
    #include "asterisk/utils.h"
    #include "asterisk/app.h"
    
    
    static char *function_fieldqty(struct ast_channel *chan, char *cmd, char *data, char *buf, size_t len)
    {
    	char *varname, *varval, workspace[256];
    	char *delim = ast_strdupa(data);
    	int fieldcount = 0;
    
    	if (delim) {
    		varname = strsep(&delim, "|");
    		pbx_retrieve_variable(chan, varname, &varval, workspace, sizeof(workspace), NULL);
    		while (strsep(&varval, delim))
    			fieldcount++;
    		snprintf(buf, len, "%d", fieldcount);
    	} else {
    		ast_log(LOG_ERROR, "Out of memory\n");
    		strncpy(buf, "1", len);
    	}
    	return buf;
    }
    
    #ifndef BUILTIN_FUNC
    static
    #endif
    struct ast_custom_function fieldqty_function = {
    	.name = "FIELDQTY",
    	.synopsis = "Count the fields, with an arbitrary delimiter",
    	.syntax = "FIELDQTY(<varname>,<delim>)",
    	.read = function_fieldqty,
    };
    
    
    static char *builtin_function_filter(struct ast_channel *chan, char *cmd, char *data, char *buf, size_t len)
    {
    	char *allowed, *string, *outbuf=buf;
    
    	string = ast_strdupa(data);
    	if (!string) {
    		ast_log(LOG_ERROR, "Out of memory");
    		return "";
    	}
    
    	allowed = strsep(&string, "|");
    
    	if (!string) {
    		ast_log(LOG_ERROR, "Usage: FILTER(<allowed-chars>,<string>)\n");
    		return "";
    	}
    
    	for ( ; *string && (buf + len - 1 > outbuf); string++) {
    		if (strchr(allowed, *string)) {
    			*outbuf = *string;
    			outbuf++;
    		}
    	}
    	*outbuf = '\0';
    	
    	return buf;
    }
    
    #ifndef BUILTIN_FUNC
    static
    #endif
    struct ast_custom_function filter_function = {
    	.name = "FILTER",
    	.synopsis = "Filter the string to include only the allowed characters",
    	.syntax = "FILTER(<allowed-chars>,<string>)",
    	.read = builtin_function_filter,
    };
    
    
    static char *builtin_function_regex(struct ast_channel *chan, char *cmd, char *data, char *buf, size_t len) 
    {
    
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    	char *arg, *earg = NULL, *tmp, errstr[256] = "";
    
    	int errcode;
    	regex_t regexbuf;
    
    
    	tmp = ast_strdupa(data);
    
    	if (!tmp) {
    		ast_log(LOG_ERROR, "Out of memory in %s(%s)\n", cmd, data);
    		return buf;
    	}
    
    	/* Regex in quotes */
    	arg = strchr(tmp, '"');
    	if (arg) {
    		arg++;
    		earg = strrchr(arg, '"');
    		if (earg) {
    			*earg++ = '\0';
    			/* Skip over any spaces before the data we are checking */
    			while (*earg == ' ')
    				earg++;
    
    	if ((errcode = regcomp(&regexbuf, arg, REG_EXTENDED | REG_NOSUB))) {
    		regerror(errcode, &regexbuf, errstr, sizeof(errstr));
    		ast_log(LOG_WARNING, "Malformed input %s(%s): %s\n", cmd, data, errstr);
    	} else {
    		if (!regexec(&regexbuf, earg ? earg : "", 0, NULL, 0))
    			ast_copy_string(buf, "1", len); 
    	}
    	regfree(&regexbuf);
    
    	return buf;
    
    }
    
    #ifndef BUILTIN_FUNC
    static
    #endif
    struct ast_custom_function regex_function = {
    	.name = "REGEX",
    	.synopsis = "Regular Expression: Returns 1 if data matches regular expression.",
    	.syntax = "REGEX(\"<regular expression>\" <data>)",
    	.read = builtin_function_regex,
    };
    
    
    static void builtin_function_array(struct ast_channel *chan, char *cmd, char *data, const char *value)
    {
    	char *varv[100];
    	char *valuev[100];
    	char *var, *value2;
    	int varcount, valuecount, i;
    
    	var = ast_strdupa(data);
    	value2 = ast_strdupa(value);
    	if (!var || !value2) {
    		ast_log(LOG_ERROR, "Out of memory\n");
    		return;
    	}
    
    	/* The functions this will generally be used with are SORT and ODBC_*, which
    	 * both return comma-delimited lists.  However, if somebody uses literal lists,
    	 * their commas will be translated to vertical bars by the load, and I don't
    	 * want them to be surprised by the result.  Hence, we prefer commas as the
    	 * delimiter, but we'll fall back to vertical bars if commas aren't found.
    	 */
    	if (strchr(var, ',')) {
    		varcount = ast_app_separate_args(var, ',', varv, 100);
    	} else {
    		varcount = ast_app_separate_args(var, '|', varv, 100);
    	}
    
    	if (strchr(value2, ',')) {
    		valuecount = ast_app_separate_args(value2, ',', valuev, 100);
    	} else {
    		valuecount = ast_app_separate_args(value2, '|', valuev, 100);
    	}
    
    	for (i = 0; i < varcount; i++) {
    		if (i < valuecount) {
    			pbx_builtin_setvar_helper(chan, varv[i], valuev[i]);
    		} else {
    			/* We could unset the variable, by passing a NULL, but due to
    			 * pushvar semantics, that could create some undesired behavior. */
    			pbx_builtin_setvar_helper(chan, varv[i], "");
    		}
    	}
    }
    
    #ifndef BUILTIN_FUNC
    static
    #endif
    struct ast_custom_function array_function = {
    	.name = "ARRAY",
    	.synopsis = "Allows setting multiple variables at once",
    	.syntax = "ARRAY(var1[,var2[...][,varN]])",
    	.write = builtin_function_array,
    	.desc =
    "The comma-separated list passed as a value to which the function is set\n"
    "will be interpreted as a set of values to which the comma-separated list\n"
    "of variable names in the argument should be set.\n"
    "Hence, Set(ARRAY(var1,var2)=1,2) will set var1 to 1 and var2 to 2\n",
    };
    
    
    static char *builtin_function_len(struct ast_channel *chan, char *cmd, char *data, char *buf, size_t len) 
    {
    	int length = 0;
    	if (data) {
    		length = strlen(data);
    	}
    	snprintf(buf, len, "%d", length);
    	return buf;
    }
    
    #ifndef BUILTIN_FUNC
    static
    #endif
    struct ast_custom_function len_function = {
    	.name = "LEN",
    	.synopsis = "Returns the length of the argument given",
    	.syntax = "LEN(<string>)",
    	.read = builtin_function_len,
    };
    
    
    static char *acf_strftime(struct ast_channel *chan, char *cmd, char *data, char *buf, size_t len) 
    {
    
    	char *format, *epoch, *timezone = NULL;
    
    		ast_log(LOG_ERROR, "Asterisk function STRFTIME() requires an argument.\n");
    
    	
    	format = ast_strdupa(data);
    	if (!format) {
    		ast_log(LOG_ERROR, "Out of memory\n");
    		return buf;
    	}
    	
    	epoch = strsep(&format, "|");
    	timezone = strsep(&format, "|");
    
    
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    	if (ast_strlen_zero(epoch) || !sscanf(epoch, "%ld", &epochi)) {
    
    		struct timeval tv = ast_tvnow();
    		epochi = tv.tv_sec;
    	}
    
    	ast_localtime(&epochi, &time, timezone);
    
    	if (!format) {
    		format = "%c";
    	}
    
    	if (!strftime(buf, len, format, &time)) {
    		ast_log(LOG_WARNING, "C function strftime() output nothing?!!\n");
    	}
    	buf[len - 1] = '\0';
    
    	return buf;
    
    }
    
    #ifndef BUILTIN_FUNC
    static
    #endif
    struct ast_custom_function strftime_function = {
    	.name = "STRFTIME",
    	.synopsis = "Returns the current date/time in a specified format.",
    	.syntax = "STRFTIME([<epoch>][,[timezone][,format]])",
    	.read = acf_strftime,
    };
    
    
    static char *function_eval(struct ast_channel *chan, char *cmd, char *data, char *buf, size_t len) 
    {
    
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    	if (ast_strlen_zero(data)) {
    
    		ast_log(LOG_WARNING, "EVAL requires an argument: EVAL(<string>)\n");
    
    	pbx_substitute_variables_helper(chan, data, buf, len - 1);
    
    	return buf;
    }
    
    #ifndef BUILTIN_FUNC
    static
    #endif
    struct ast_custom_function eval_function = {
    	.name = "EVAL",
    	.synopsis = "Evaluate stored variables.",
    	.syntax = "EVAL(<variable>)",
    	.desc = "Using EVAL basically causes a string to be evaluated twice.\n"
    		"When a variable or expression is in the dialplan, it will be\n"
    		"evaluated at runtime. However, if the result of the evaluation\n"
    		"is in fact a variable or expression, using EVAL will have it\n"
    		"evaluated a second time. For example, if the variable ${MYVAR}\n"
    		"contains \"${OTHERVAR}\", then the result of putting ${EVAL(${MYVAR})}\n"
    		"in the dialplan will be the contents of the variable, OTHERVAR.\n"
    		"Normally, by just putting ${MYVAR} in the dialplan, you would be\n"
    		"left with \"${OTHERVAR}\".\n", 
    	.read = function_eval,
    };