Bug 5961 - new RAND() function

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@7920 65c4cc65-6c06-0410-ace0-fbb531ad65f3

asterisk.c

@@ -211,6 +211,8 @@ static int shuttingdown = 0;
 static int restartnow = 0;
 static pthread_t consolethread = AST_PTHREADT_NULL;
 
+static char randompool[256];
+
 #if !defined(LOW_MEMORY)
 struct file_version {
 	AST_LIST_ENTRY(file_version) list;
@@ -2288,7 +2290,7 @@ int main(int argc, char *argv[])
 	   Asterisk is started
 	*/
 	srand((unsigned int) getpid() + (unsigned int) time(NULL));
-	srandom((unsigned int) getpid() + (unsigned int) time(NULL));
+	initstate((unsigned int) getpid() * 65536 + (unsigned int) time(NULL), randompool, sizeof(randompool));
 
 	if (init_logger()) {
 		printf(term_quit());

funcs/func_rand.c

@@ -0,0 +1,143 @@
+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 2006, Digium, Inc.
+ * Copyright (C) 2006, Claude Patry
+ *
+ * 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 Generate Random Number
+ * 
+ * \author Claude Patry <cpatry@gmail.com>
+ * \author Tilghman Lesher ( http://asterisk.drunkcoder.com/ )
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <sys/types.h>
+
+#include "asterisk.h"
+
+/* ASTERISK_FILE_VERSION(__FILE__, "$Revision: 7682 $") */
+
+#include "asterisk/channel.h"
+#include "asterisk/pbx.h"
+#include "asterisk/logger.h"
+#include "asterisk/utils.h"
+#include "asterisk/app.h"
+#ifndef BUILTIN_FUNC
+#include "asterisk/module.h"
+#endif
+
+
+STANDARD_LOCAL_USER;
+
+LOCAL_USER_DECL;
+
+
+static char *acf_rand_exec(struct ast_channel *chan, char *cmd, char *data, char *buffer, size_t buflen)
+{
+	struct localuser *u;
+	char *args[2] = { "", "" }, *s;
+	int min_int, response_int, max_int;
+
+	LOCAL_USER_ACF_ADD(u);
+
+	if (!(s = ast_strdupa(data))) {
+		ast_log(LOG_WARNING, "Out of memory\n");
+		*buffer = '\0';
+		LOCAL_USER_REMOVE(u);
+		return buffer;
+	}
+
+	ast_app_separate_args(s, '|', args, sizeof(args) / sizeof(args[0]));
+
+	if (ast_strlen_zero(args[0]) || sscanf(args[0], "%d", &min_int) != 1) {
+		min_int = 0;
+	}
+
+	if (ast_strlen_zero(args[1]) || sscanf(args[1], "%d", &max_int) != 1) {
+		max_int = RAND_MAX;
+	}
+
+	if (max_int < min_int) {
+		int tmp = max_int;
+		max_int = min_int;
+		min_int = tmp;
+		ast_log(LOG_DEBUG, "max<min\n");
+	}
+
+	response_int = min_int + (ast_random() % (max_int - min_int + 1));
+	ast_log(LOG_DEBUG, "%d was the lucky number in range [%d,%d]\n", response_int, min_int, max_int);
+	snprintf(buffer, buflen, "%d", response_int);
+
+	LOCAL_USER_REMOVE(u);
+	return buffer;
+}
+
+#ifndef BUILTIN_FUNC
+static
+#endif
+struct ast_custom_function acf_rand = {
+	.name = "RAND",
+	.synopsis = "Choose a random number in a range",
+	.syntax = "RAND([min][,max])",
+	.desc =
+"Choose a random number between min and max.  Min defaults to 0, if not\n"
+"specified, while max defaults to RAND_MAX (2147483647 on many systems).\n"
+"  Example:  Set(junky=${RAND(1,8)}); \n"
+"  Sets junky to a random number between 1 and 8, inclusive.\n",
+	.read = acf_rand_exec,
+};
+
+
+#ifndef BUILTIN_FUNC
+
+static char *tdesc = "Generate a random number";
+
+int unload_module(void)
+{
+	ast_custom_function_unregister(&acf_rand);
+
+	STANDARD_HANGUP_LOCALUSERS;
+
+	return 0;
+}
+
+int load_module(void)
+{
+	return ast_custom_function_register(&acf_rand);
+}
+
+char *description(void)
+{
+       return tdesc;
+}
+
+int usecount(void)
+{
+	int res;
+
+	STANDARD_USECOUNT(res);
+
+	return res;
+}
+
+char *key()
+{
+       return ASTERISK_GPL_KEY;
+}
+
+#endif

include/asterisk/utils.h

@@ -235,4 +235,10 @@ char *ast_process_quotes_and_slashes(char *start, char find, char replace_with);
 int getloadavg(double *list, int nelem);
 #endif
 
+#ifdef linux
+#define ast_random random
+#else
+long int ast_random(void);
+#endif
+
 #endif /* _ASTERISK_UTILS_H */

utils.c

@@ -881,6 +881,19 @@ int getloadavg(double *list, int nelem)
 #endif /* linux */
 #endif /* !defined(_BSD_SOURCE) */
 
+/* glibc puts a lock inside random(3), so that the results are thread-safe.
+ * BSD libc (and others) do not. */
+#ifndef linux
+long int ast_random(void)
+{
+	long int res;
+	ast_mutex_lock(&randomlock);
+	res = random();
+	ast_mutex_unlock(&randomlock);
+	return res;
+}
+#endif
+
 char *ast_process_quotes_and_slashes(char *start, char find, char replace_with)
 {
  	char *dataPut = start;