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 /*** DOCUMENTATION
  38         <application name="System" language="en_US">
  39                 <synopsis>
  40                         Execute a system command.
  41                 </synopsis>
  42                 <syntax>
  43                         <parameter name="command" required="true">
  44                                 <para>Command to execute</para>
  45                         </parameter>
  46                 </syntax>
  47                 <description>
  48                         <para>Executes a command  by  using  system(). If the command
  49                         fails, the console should report a fallthrough.</para>
  50                         <para>Result of execution is returned in the <variable>SYSTEMSTATUS</variable> channel variable:</para>
  51                         <variablelist>
  52                                 <variable name="SYSTEMSTATUS">
  53                                         <value name="FAILURE">
  54                                                 Could not execute the specified command.
  55                                         </value>
  56                                         <value name="SUCCESS">
  57                                                 Specified command successfully executed.
  58                                         </value>
  59                                 </variable>
  60                         </variablelist>
  61                 </description>
  62         </application>
  63         <application name="TrySystem" language="en_US">
  64                 <synopsis>
  65                         Try executing a system command.
  66                 </synopsis>
  67                 <syntax>
  68                         <parameter name="command" required="true">
  69                                 <para>Command to execute</para>
  70                         </parameter>
  71                 </syntax>
  72                 <description>
  73                         <para>Executes a command  by  using  system().</para>
  74                         <para>Result of execution is returned in the <variable>SYSTEMSTATUS</variable> channel variable:</para>
  75                         <variablelist>
  76                                 <variable name="SYSTEMSTATUS">
  77                                         <value name="FAILURE">
  78                                                 Could not execute the specified command.
  79                                         </value>
  80                                         <value name="SUCCESS">
  81                                                 Specified command successfully executed.
  82                                         </value>
  83                                         <value name="APPERROR">
  84                                                 Specified command successfully executed, but returned error code.
  85                                         </value>
  86                                 </variable>
  87                         </variablelist>
  88                 </description>
  89         </application>
  90
  91  ***/
  92
  93 static char *app = "System";
  94
  95 static char *app2 = "TrySystem";
  96
  97 static char *chanvar = "SYSTEMSTATUS";
  98
  99 static int system_exec_helper(struct ast_channel *chan, void *data, int failmode)
 100 {
 101         int res = 0;
 102
 103         if (ast_strlen_zero(data)) {
 104                 ast_log(LOG_WARNING, "System requires an argument(command)\n");
 105                 pbx_builtin_setvar_helper(chan, chanvar, "FAILURE");
 106                 return failmode;
 107         }
 108
 109         ast_autoservice_start(chan);
 110
 111         /* Do our thing here */
 112         res = ast_safe_system((char *)data);
 113         if ((res < 0) && (errno != ECHILD)) {
 114                 ast_log(LOG_WARNING, "Unable to execute '%s'\n", (char *)data);
 115                 pbx_builtin_setvar_helper(chan, chanvar, "FAILURE");
 116                 res = failmode;
 117         } else if (res == 127) {
 118                 ast_log(LOG_WARNING, "Unable to execute '%s'\n", (char *)data);
 119                 pbx_builtin_setvar_helper(chan, chanvar, "FAILURE");
 120                 res = failmode;
 121         } else {
 122                 if (res < 0)
 123                         res = 0;
 124                 if (res != 0)
 125                         pbx_builtin_setvar_helper(chan, chanvar, "APPERROR");
 126                 else
 127                         pbx_builtin_setvar_helper(chan, chanvar, "SUCCESS");
 128                 res = 0;
 129         }
 130
 131         ast_autoservice_stop(chan);
 132
 133         return res;
 134 }
 135
 136 static int system_exec(struct ast_channel *chan, void *data)
 137 {
 138         return system_exec_helper(chan, data, -1);
 139 }
 140
 141 static int trysystem_exec(struct ast_channel *chan, void *data)
 142 {
 143         return system_exec_helper(chan, data, 0);
 144 }
 145
 146 static int unload_module(void)
 147 {
 148         int res;
 149
 150         res = ast_unregister_application(app);
 151         res |= ast_unregister_application(app2);
 152
 153         return res;
 154 }
 155
 156 static int load_module(void)
 157 {
 158         int res;
 159
 160         res = ast_register_application_xml(app2, trysystem_exec);
 161         res |= ast_register_application_xml(app, system_exec);
 162
 163         return res;
 164 }
 165
 166 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Generic System() application");