Add the app_eval.c file

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@2375 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_eval.c

+/*
+ * Asterisk -- A telephony toolkit for Linux.
+ *
+ * Eval application
+ *
+ * Copyright (c) 2004 Tilghman Lesher.  All rights reserved.
+ *
+ * Tilghman Lesher <app_eval__v001@the-tilghman.com>
+ *
+ * $Id$
+ *
+ * This code is released by the author with no restrictions on usage.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <asterisk/file.h>
+#include <asterisk/logger.h>
+#include <asterisk/options.h>
+#include <asterisk/channel.h>
+#include <asterisk/pbx.h>
+#include <asterisk/module.h>
+
+/* Maximum length of any variable */
+#define MAXRESULT	1024
+
+static char *tdesc = "Reevaluates strings";
+
+static char *app_eval = "Eval";
+
+static char *eval_synopsis = "Eval(newvar=somestring)";
+
+static char *eval_descrip =
+"Eval(newvar=somestring)\n"
+"  Normally Asterisk evaluates variables inline.  But what if you want to\n"
+"store variable offsets in a database, to be evaluated later?  Eval is\n"
+"the answer, by allowing a string to be evaluated twice in the dialplan,\n"
+"the first time as part of the normal dialplan, and the second using Eval.\n";
+
+STANDARD_LOCAL_USER;
+
+LOCAL_USER_DECL;
+
+static int eval_exec(struct ast_channel *chan, void *data)
+{
+	int res=0;
+	struct localuser *u;
+	char *s, *newvar=NULL, tmp[MAXRESULT];
+
+	LOCAL_USER_ADD(u);
+
+	/* Check and parse arguments */
+	if (data) {
+		s = ast_strdupa((char *)data);
+		if (s) {
+			newvar = strsep(&s, "=");
+			if (newvar && (newvar[0] != '\0')) {
+				memset(tmp, 0, MAXRESULT);
+				pbx_substitute_variables_helper(chan, s, tmp, MAXRESULT - 1);
+				pbx_builtin_setvar_helper(chan, newvar, tmp);
+			}
+		} else {
+			ast_log(LOG_ERROR, "Out of memory\n");
+			res = -1;
+		}
+	}
+
+	LOCAL_USER_REMOVE(u);
+	return res;
+}
+
+int unload_module(void)
+{
+	STANDARD_HANGUP_LOCALUSERS;
+	return ast_unregister_application(app_eval);
+}
+
+int load_module(void)
+{
+	return ast_register_application(app_eval, eval_exec, eval_synopsis, eval_descrip);
+}
+
+char *description(void)
+{
+	return tdesc;
+}
+
+int usecount(void)
+{
+	int res;
+	STANDARD_USECOUNT(res);
+	return res;
+}
+
+char *key()
+{
+	return ASTERISK_GPL_KEY;
+}