apps/app_system.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * Copyright (C) 1999 - 2005, Digium, Inc.
   5  *
   6  * Mark Spencer <markster@digium.com>
   7  *
   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.
  13  *
  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.
  17  */
  18
  19 /*! \file
  20  *
  21  * \brief Execute arbitrary system commands
  22  *
  23  * \author Mark Spencer <markster@digium.com>
  24  *
  25  * \ingroup applications
  26  */
  27
  28 #include "asterisk.h"
  29
  30 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  31
  32 #include "asterisk/pbx.h"
  33 #include "asterisk/module.h"
  34 #include "asterisk/app.h"
  35 #include "asterisk/channel.h"   /* autoservice */
  36
  37 static char *app = "System";
  38
  39 static char *app2 = "TrySystem";
  40
  41 static char *synopsis = "Execute a system command";
  42
  43 static char *synopsis2 = "Try executing a system command";
  44
  45 static char *chanvar = "SYSTEMSTATUS";
  46
  47 static char *descrip =
  48 "  System(command): Executes a command  by  using  system(). If the command\n"
  49 "fails, the console should report a fallthrough. \n"
  50 "Result of execution is returned in the SYSTEMSTATUS channel variable:\n"
  51 "   FAILURE     Could not execute the specified command\n"
  52 "   SUCCESS     Specified command successfully executed\n";
  53
  54 static char *descrip2 =
  55 "  TrySystem(command): Executes a command  by  using  system().\n"
  56 "on any situation.\n"
  57 "Result of execution is returned in the SYSTEMSTATUS channel variable:\n"
  58 "   FAILURE     Could not execute the specified command\n"
  59 "   SUCCESS     Specified command successfully executed\n"
  60 "   APPERROR    Specified command successfully executed, but returned error code\n";
  61
  62 static int system_exec_helper(struct ast_channel *chan, void *data, int failmode)
  63 {
  64         int res = 0;
  65
  66         if (ast_strlen_zero(data)) {
  67                 ast_log(LOG_WARNING, "System requires an argument(command)\n");
  68                 pbx_builtin_setvar_helper(chan, chanvar, "FAILURE");
  69                 return failmode;
  70         }
  71
  72         ast_autoservice_start(chan);
  73
  74         /* Do our thing here */
  75         res = ast_safe_system((char *)data);
  76         if ((res < 0) && (errno != ECHILD)) {
  77                 ast_log(LOG_WARNING, "Unable to execute '%s'\n", (char *)data);
  78                 pbx_builtin_setvar_helper(chan, chanvar, "FAILURE");
  79                 res = failmode;
  80         } else if (res == 127) {
  81                 ast_log(LOG_WARNING, "Unable to execute '%s'\n", (char *)data);
  82                 pbx_builtin_setvar_helper(chan, chanvar, "FAILURE");
  83                 res = failmode;
  84         } else {
  85                 if (res < 0)
  86                         res = 0;
  87                 if (res != 0)
  88                         pbx_builtin_setvar_helper(chan, chanvar, "APPERROR");
  89                 else
  90                         pbx_builtin_setvar_helper(chan, chanvar, "SUCCESS");
  91                 res = 0;
  92         }
  93
  94         ast_autoservice_stop(chan);
  95
  96         return res;
  97 }
  98
  99 static int system_exec(struct ast_channel *chan, void *data)
 100 {
 101         return system_exec_helper(chan, data, -1);
 102 }
 103
 104 static int trysystem_exec(struct ast_channel *chan, void *data)
 105 {
 106         return system_exec_helper(chan, data, 0);
 107 }
 108
 109 static int unload_module(void)
 110 {
 111         int res;
 112
 113         res = ast_unregister_application(app);
 114         res |= ast_unregister_application(app2);
 115
 116         return res;
 117 }
 118
 119 static int load_module(void)
 120 {
 121         int res;
 122
 123         res = ast_register_application(app2, trysystem_exec, synopsis2, descrip2);
 124         res |= ast_register_application(app, system_exec, synopsis, descrip);
 125
 126         return res;
 127 }
 128
 129 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Generic System() application");