2 * Asterisk -- An open source telephony toolkit.
4 * Copyright (c) 2004-2006 Tilghman Lesher <app_stack_v002@the-tilghman.com>.
6 * This code is released by the author with no restrictions on usage.
8 * See http://www.asterisk.org for more information about
9 * the Asterisk project. Please do not directly contact
10 * any of the maintainers of this project for assistance;
11 * the project provides a web site, mailing lists and IRC
12 * channels for your use.
14 * This program is free software, distributed under the terms of
15 * the GNU General Public License Version 2. See the LICENSE file
16 * at the top of the source tree.
21 * \brief Stack applications Gosub, Return, etc.
23 * \author Tilghman Lesher <app_stack_v002@the-tilghman.com>
25 * \ingroup applications
30 ASTERISK_FILE_VERSION(__FILE__
, "$Revision$")
37 #include "asterisk/options.h"
38 #include "asterisk/logger.h"
39 #include "asterisk/channel.h"
40 #include "asterisk/chanvars.h"
41 #include "asterisk/pbx.h"
42 #include "asterisk/module.h"
43 #include "asterisk/config.h"
45 #define STACKVAR "~GOSUB~STACK~"
48 static const char *app_gosub
= "Gosub";
49 static const char *app_gosubif
= "GosubIf";
50 static const char *app_return
= "Return";
51 static const char *app_pop
= "StackPop";
53 static const char *gosub_synopsis
= "Jump to label, saving return address";
54 static const char *gosubif_synopsis
= "Conditionally jump to label, saving return address";
55 static const char *return_synopsis
= "Return from gosub routine";
56 static const char *pop_synopsis
= "Remove one address from gosub stack";
58 static const char *gosub_descrip
=
59 "Gosub([[context|]exten|]priority)\n"
60 " Jumps to the label specified, saving the return address.\n";
61 static const char *gosubif_descrip
=
62 "GosubIf(condition?labeliftrue[:labeliffalse])\n"
63 " If the condition is true, then jump to labeliftrue. If false, jumps to\n"
64 "labeliffalse, if specified. In either case, a jump saves the return point\n"
65 "in the dialplan, to be returned to with a Return.\n";
66 static const char *return_descrip
=
68 " Jumps to the last label on the stack, removing it.\n";
69 static const char *pop_descrip
=
71 " Removes last label on the stack, discarding it.\n";
74 static int pop_exec(struct ast_channel
*chan
, void *data
)
76 pbx_builtin_setvar_helper(chan
, STACKVAR
, NULL
);
81 static int return_exec(struct ast_channel
*chan
, void *data
)
83 const char *label
= pbx_builtin_getvar_helper(chan
, STACKVAR
);
85 if (ast_strlen_zero(label
)) {
86 ast_log(LOG_ERROR
, "Return without Gosub: stack is empty\n");
88 } else if (ast_parseable_goto(chan
, label
)) {
89 ast_log(LOG_WARNING
, "No next statement after Gosub?\n");
93 pbx_builtin_setvar_helper(chan
, STACKVAR
, NULL
);
97 static int gosub_exec(struct ast_channel
*chan
, void *data
)
99 char newlabel
[AST_MAX_EXTENSION
* 2 + 3 + 11];
100 struct ast_module_user
*u
;
102 if (ast_strlen_zero(data
)) {
103 ast_log(LOG_ERROR
, "%s requires an argument: %s([[context|]exten|]priority)\n", app_gosub
, app_gosub
);
107 u
= ast_module_user_add(chan
);
108 snprintf(newlabel
, sizeof(newlabel
), "%s|%s|%d", chan
->context
, chan
->exten
, chan
->priority
+ 1);
110 if (ast_parseable_goto(chan
, data
)) {
111 ast_module_user_remove(u
);
115 pbx_builtin_pushvar_helper(chan
, STACKVAR
, newlabel
);
116 ast_module_user_remove(u
);
121 static int gosubif_exec(struct ast_channel
*chan
, void *data
)
123 struct ast_module_user
*u
;
124 char *condition
="", *label1
, *label2
, *args
;
127 if (ast_strlen_zero(data
)) {
128 ast_log(LOG_WARNING
, "GosubIf requires an argument\n");
132 args
= ast_strdupa(data
);
134 u
= ast_module_user_add(chan
);
136 condition
= strsep(&args
, "?");
137 label1
= strsep(&args
, ":");
140 if (pbx_checkcondition(condition
)) {
142 res
= gosub_exec(chan
, label1
);
145 res
= gosub_exec(chan
, label2
);
148 ast_module_user_remove(u
);
152 static int unload_module(void)
154 ast_unregister_application(app_return
);
155 ast_unregister_application(app_pop
);
156 ast_unregister_application(app_gosubif
);
157 ast_unregister_application(app_gosub
);
159 ast_module_user_hangup_all();
164 static int load_module(void)
166 ast_register_application(app_pop
, pop_exec
, pop_synopsis
, pop_descrip
);
167 ast_register_application(app_return
, return_exec
, return_synopsis
, return_descrip
);
168 ast_register_application(app_gosubif
, gosubif_exec
, gosubif_synopsis
, gosubif_descrip
);
169 ast_register_application(app_gosub
, gosub_exec
, gosub_synopsis
, gosub_descrip
);
174 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY
, "Stack Routines");