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 /*** MODULEINFO
  29         <support_level>core</support_level>
  30  ***/
  31
  32 #include "asterisk.h"
  33
  34 ASTERISK_REGISTER_FILE()
  35
  36 #include "asterisk/pbx.h"
  37 #include "asterisk/module.h"
  38 #include "asterisk/app.h"
  39 #include "asterisk/channel.h"   /* autoservice */
  40 #include "asterisk/strings.h"
  41 #include "asterisk/threadstorage.h"
  42
  43 /*** DOCUMENTATION
  44         <application name="System" language="en_US">
  45                 <synopsis>
  46                         Execute a system command.
  47                 </synopsis>
  48                 <syntax>
  49                         <parameter name="command" required="true">
  50                                 <para>Command to execute</para>
  51                         </parameter>
  52                 </syntax>
  53                 <description>
  54                         <para>Executes a command  by  using  system(). If the command
  55                         fails, the console should report a fallthrough.</para>
  56                         <para>Result of execution is returned in the <variable>SYSTEMSTATUS</variable> channel variable:</para>
  57                         <variablelist>
  58                                 <variable name="SYSTEMSTATUS">
  59                                         <value name="FAILURE">
  60                                                 Could not execute the specified command.
  61                                         </value>
  62                                         <value name="SUCCESS">
  63                                                 Specified command successfully executed.
  64                                         </value>
  65                                 </variable>
  66                         </variablelist>
  67                 </description>
  68         </application>
  69         <application name="TrySystem" language="en_US">
  70                 <synopsis>
  71                         Try executing a system command.
  72                 </synopsis>
  73                 <syntax>
  74                         <parameter name="command" required="true">
  75                                 <para>Command to execute</para>
  76                         </parameter>
  77                 </syntax>
  78                 <description>
  79                         <para>Executes a command  by  using  system().</para>
  80                         <para>Result of execution is returned in the <variable>SYSTEMSTATUS</variable> channel variable:</para>
  81                         <variablelist>
  82                                 <variable name="SYSTEMSTATUS">
  83                                         <value name="FAILURE">
  84                                                 Could not execute the specified command.
  85                                         </value>
  86                                         <value name="SUCCESS">
  87                                                 Specified command successfully executed.
  88                                         </value>
  89                                         <value name="APPERROR">
  90                                                 Specified command successfully executed, but returned error code.
  91                                         </value>
  92                                 </variable>
  93                         </variablelist>
  94                 </description>
  95         </application>
  96
  97  ***/
  98
  99 AST_THREADSTORAGE(buf_buf);
 100
 101 static char *app = "System";
 102
 103 static char *app2 = "TrySystem";
 104
 105 static char *chanvar = "SYSTEMSTATUS";
 106
 107 static int system_exec_helper(struct ast_channel *chan, const char *data, int failmode)
 108 {
 109         int res = 0;
 110         struct ast_str *buf = ast_str_thread_get(&buf_buf, 16);
 111         char *cbuf;
 112
 113         if (ast_strlen_zero(data)) {
 114                 ast_log(LOG_WARNING, "System requires an argument(command)\n");
 115                 pbx_builtin_setvar_helper(chan, chanvar, "FAILURE");
 116                 return failmode;
 117         }
 118
 119         ast_autoservice_start(chan);
 120
 121         /* Do our thing here */
 122         ast_str_get_encoded_str(&buf, 0, (char *) data);
 123         cbuf = ast_str_buffer(buf);
 124
 125         if (strchr("\"'", cbuf[0]) && cbuf[ast_str_strlen(buf) - 1] == cbuf[0]) {
 126                 cbuf[ast_str_strlen(buf) - 1] = '\0';
 127                 cbuf++;
 128                 ast_log(LOG_NOTICE, "It is not necessary to quote the argument to the System application.\n");
 129         }
 130
 131         res = ast_safe_system(cbuf);
 132
 133         if ((res < 0) && (errno != ECHILD)) {
 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 if (res == 127) {
 138                 ast_log(LOG_WARNING, "Unable to execute '%s'\n", (char *)data);
 139                 pbx_builtin_setvar_helper(chan, chanvar, "FAILURE");
 140                 res = failmode;
 141         } else {
 142                 if (res < 0)
 143                         res = 0;
 144                 if (res != 0)
 145                         pbx_builtin_setvar_helper(chan, chanvar, "APPERROR");
 146                 else
 147                         pbx_builtin_setvar_helper(chan, chanvar, "SUCCESS");
 148                 res = 0;
 149         }
 150
 151         ast_autoservice_stop(chan);
 152
 153         return res;
 154 }
 155
 156 static int system_exec(struct ast_channel *chan, const char *data)
 157 {
 158         return system_exec_helper(chan, data, -1);
 159 }
 160
 161 static int trysystem_exec(struct ast_channel *chan, const char *data)
 162 {
 163         return system_exec_helper(chan, data, 0);
 164 }
 165
 166 static int unload_module(void)
 167 {
 168         int res;
 169
 170         res = ast_unregister_application(app);
 171         res |= ast_unregister_application(app2);
 172
 173         return res;
 174 }
 175
 176 static int load_module(void)
 177 {
 178         int res;
 179
 180         res = ast_register_application_xml(app2, trysystem_exec);
 181         res |= ast_register_application_xml(app, system_exec);
 182
 183         return res;
 184 }
 185
 186 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Generic System() application");