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 #include "asterisk/strings.h"
  37 #include "asterisk/threadstorage.h"
  38
  39 /*** DOCUMENTATION
  40         <application name="System" language="en_US">
  41                 <synopsis>
  42                         Execute a system command.
  43                 </synopsis>
  44                 <syntax>
  45                         <parameter name="command" required="true">
  46                                 <para>Command to execute</para>
  47                         </parameter>
  48                 </syntax>
  49                 <description>
  50                         <para>Executes a command  by  using  system(). If the command
  51                         fails, the console should report a fallthrough.</para>
  52                         <para>Result of execution is returned in the <variable>SYSTEMSTATUS</variable> channel variable:</para>
  53                         <variablelist>
  54                                 <variable name="SYSTEMSTATUS">
  55                                         <value name="FAILURE">
  56                                                 Could not execute the specified command.
  57                                         </value>
  58                                         <value name="SUCCESS">
  59                                                 Specified command successfully executed.
  60                                         </value>
  61                                 </variable>
  62                         </variablelist>
  63                 </description>
  64         </application>
  65         <application name="TrySystem" language="en_US">
  66                 <synopsis>
  67                         Try executing a system command.
  68                 </synopsis>
  69                 <syntax>
  70                         <parameter name="command" required="true">
  71                                 <para>Command to execute</para>
  72                         </parameter>
  73                 </syntax>
  74                 <description>
  75                         <para>Executes a command  by  using  system().</para>
  76                         <para>Result of execution is returned in the <variable>SYSTEMSTATUS</variable> channel variable:</para>
  77                         <variablelist>
  78                                 <variable name="SYSTEMSTATUS">
  79                                         <value name="FAILURE">
  80                                                 Could not execute the specified command.
  81                                         </value>
  82                                         <value name="SUCCESS">
  83                                                 Specified command successfully executed.
  84                                         </value>
  85                                         <value name="APPERROR">
  86                                                 Specified command successfully executed, but returned error code.
  87                                         </value>
  88                                 </variable>
  89                         </variablelist>
  90                 </description>
  91         </application>
  92
  93  ***/
  94
  95 AST_THREADSTORAGE(buf_buf);
  96
  97 static char *app = "System";
  98
  99 static char *app2 = "TrySystem";
 100
 101 static char *chanvar = "SYSTEMSTATUS";
 102
 103 static int system_exec_helper(struct ast_channel *chan, const char *data, int failmode)
 104 {
 105         int res = 0;
 106         struct ast_str *buf = ast_str_thread_get(&buf_buf, 16);
 107         char *cbuf;
 108
 109         if (ast_strlen_zero(data)) {
 110                 ast_log(LOG_WARNING, "System requires an argument(command)\n");
 111                 pbx_builtin_setvar_helper(chan, chanvar, "FAILURE");
 112                 return failmode;
 113         }
 114
 115         ast_autoservice_start(chan);
 116
 117         /* Do our thing here */
 118         ast_str_get_encoded_str(&buf, 0, (char *) data);
 119         cbuf = ast_str_buffer(buf);
 120
 121         if (strchr("\"'", cbuf[0]) && cbuf[ast_str_strlen(buf) - 1] == cbuf[0]) {
 122                 cbuf[ast_str_strlen(buf) - 1] = '\0';
 123                 cbuf++;
 124                 ast_log(LOG_NOTICE, "It is not necessary to quote the argument to the System application.\n");
 125         }
 126
 127         res = ast_safe_system(cbuf);
 128
 129         if ((res < 0) && (errno != ECHILD)) {
 130                 ast_log(LOG_WARNING, "Unable to execute '%s'\n", (char *)data);
 131                 pbx_builtin_setvar_helper(chan, chanvar, "FAILURE");
 132                 res = failmode;
 133         } else if (res == 127) {
 134                 ast_log(LOG_WARNING, "Unable to execute '%s'\n", (char *)data);
 135                 pbx_builtin_setvar_helper(chan, chanvar, "FAILURE");
 136                 res = failmode;
 137         } else {
 138                 if (res < 0)
 139                         res = 0;
 140                 if (res != 0)
 141                         pbx_builtin_setvar_helper(chan, chanvar, "APPERROR");
 142                 else
 143                         pbx_builtin_setvar_helper(chan, chanvar, "SUCCESS");
 144                 res = 0;
 145         }
 146
 147         ast_autoservice_stop(chan);
 148
 149         return res;
 150 }
 151
 152 static int system_exec(struct ast_channel *chan, const char *data)
 153 {
 154         return system_exec_helper(chan, data, -1);
 155 }
 156
 157 static int trysystem_exec(struct ast_channel *chan, const char *data)
 158 {
 159         return system_exec_helper(chan, data, 0);
 160 }
 161
 162 static int unload_module(void)
 163 {
 164         int res;
 165
 166         res = ast_unregister_application(app);
 167         res |= ast_unregister_application(app2);
 168
 169         return res;
 170 }
 171
 172 static int load_module(void)
 173 {
 174         int res;
 175
 176         res = ast_register_application_xml(app2, trysystem_exec);
 177         res |= ast_register_application_xml(app, system_exec);
 178
 179         return res;
 180 }
 181
 182 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Generic System() application");