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app_while.c

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00001 /*
00002  * Asterisk -- An open source telephony toolkit.
00003  *
00004  * Copyright 2004 - 2005, Anthony Minessale <anthmct@yahoo.com>
00005  *
00006  * Anthony Minessale <anthmct@yahoo.com>
00007  *
00008  * See http://www.asterisk.org for more information about
00009  * the Asterisk project. Please do not directly contact
00010  * any of the maintainers of this project for assistance;
00011  * the project provides a web site, mailing lists and IRC
00012  * channels for your use.
00013  *
00014  * This program is free software, distributed under the terms of
00015  * the GNU General Public License Version 2. See the LICENSE file
00016  * at the top of the source tree.
00017  */
00018 
00019 /*! \file
00020  *
00021  * \brief While Loop and ExecIf Implementations
00022  * 
00023  * \ingroup applications
00024  */
00025 
00026 #include <stdlib.h>
00027 #include <stdio.h>
00028 #include <string.h>
00029 #include <unistd.h>
00030 
00031 #include "asterisk.h"
00032 
00033 ASTERISK_FILE_VERSION(__FILE__, "$Revision: 24911 $")
00034 
00035 #include "asterisk/file.h"
00036 #include "asterisk/logger.h"
00037 #include "asterisk/channel.h"
00038 #include "asterisk/utils.h"
00039 #include "asterisk/config.h"
00040 #include "asterisk/pbx.h"
00041 #include "asterisk/module.h"
00042 #include "asterisk/lock.h"
00043 #include "asterisk/options.h"
00044 
00045 #define ALL_DONE(u,ret) {LOCAL_USER_REMOVE(u); return ret;}
00046 
00047 
00048 static char *exec_app = "ExecIf";
00049 static char *exec_desc = 
00050 "Usage:  ExecIF (<expr>|<app>|<data>)\n"
00051 "If <expr> is true, execute and return the result of <app>(<data>).\n"
00052 "If <expr> is true, but <app> is not found, then the application\n"
00053 "will return a non-zero value.";
00054 static char *exec_synopsis = "Conditional exec";
00055 
00056 static char *start_app = "While";
00057 static char *start_desc = 
00058 "Usage:  While(<expr>)\n"
00059 "Start a While Loop.  Execution will return to this point when\n"
00060 "EndWhile is called until expr is no longer true.\n";
00061 
00062 static char *start_synopsis = "Start A While Loop";
00063 
00064 
00065 static char *stop_app = "EndWhile";
00066 static char *stop_desc = 
00067 "Usage:  EndWhile()\n"
00068 "Return to the previous called While\n\n";
00069 
00070 static char *stop_synopsis = "End A While Loop";
00071 
00072 static char *tdesc = "While Loops and Conditional Execution";
00073 
00074 
00075 
00076 STANDARD_LOCAL_USER;
00077 
00078 LOCAL_USER_DECL;
00079 
00080 static int execif_exec(struct ast_channel *chan, void *data) {
00081    int res=0;
00082    struct localuser *u;
00083    char *myapp = NULL;
00084    char *mydata = NULL;
00085    char *expr = NULL;
00086    struct ast_app *app = NULL;
00087 
00088    LOCAL_USER_ADD(u);
00089 
00090    expr = ast_strdupa(data);
00091    if (!expr) {
00092       ast_log(LOG_ERROR, "Out of memory\n");
00093       LOCAL_USER_REMOVE(u);
00094       return -1;
00095    }
00096 
00097    if ((myapp = strchr(expr,'|'))) {
00098       *myapp = '\0';
00099       myapp++;
00100       if ((mydata = strchr(myapp,'|'))) {
00101          *mydata = '\0';
00102          mydata++;
00103       } else
00104          mydata = "";
00105 
00106       if (pbx_checkcondition(expr)) { 
00107          if ((app = pbx_findapp(myapp))) {
00108             res = pbx_exec(chan, app, mydata, 1);
00109          } else {
00110             ast_log(LOG_WARNING, "Count not find application! (%s)\n", myapp);
00111             res = -1;
00112          }
00113       }
00114    } else {
00115       ast_log(LOG_ERROR,"Invalid Syntax.\n");
00116       res = -1;
00117    }
00118       
00119    ALL_DONE(u,res);
00120 }
00121 
00122 #define VAR_SIZE 64
00123 
00124 
00125 static char *get_index(struct ast_channel *chan, const char *prefix, int index) {
00126    char varname[VAR_SIZE];
00127 
00128    snprintf(varname, VAR_SIZE, "%s_%d", prefix, index);
00129    return pbx_builtin_getvar_helper(chan, varname);
00130 }
00131 
00132 static struct ast_exten *find_matching_priority(struct ast_context *c, const char *exten, int priority, const char *callerid)
00133 {
00134    struct ast_exten *e;
00135    struct ast_include *i;
00136    struct ast_context *c2;
00137 
00138    for (e=ast_walk_context_extensions(c, NULL); e; e=ast_walk_context_extensions(c, e)) {
00139       if (ast_extension_match(ast_get_extension_name(e), exten)) {
00140          int needmatch = ast_get_extension_matchcid(e);
00141          if ((needmatch && ast_extension_match(ast_get_extension_cidmatch(e), callerid)) ||
00142             (!needmatch)) {
00143             /* This is the matching extension we want */
00144             struct ast_exten *p;
00145             for (p=ast_walk_extension_priorities(e, NULL); p; p=ast_walk_extension_priorities(e, p)) {
00146                if (priority != ast_get_extension_priority(p))
00147                   continue;
00148                return p;
00149             }
00150          }
00151       }
00152    }
00153 
00154    /* No match; run through includes */
00155    for (i=ast_walk_context_includes(c, NULL); i; i=ast_walk_context_includes(c, i)) {
00156       for (c2=ast_walk_contexts(NULL); c2; c2=ast_walk_contexts(c2)) {
00157          if (!strcmp(ast_get_context_name(c2), ast_get_include_name(i))) {
00158             e = find_matching_priority(c2, exten, priority, callerid);
00159             if (e)
00160                return e;
00161          }
00162       }
00163    }
00164    return NULL;
00165 }
00166 
00167 static int find_matching_endwhile(struct ast_channel *chan)
00168 {
00169    struct ast_context *c;
00170    int res=-1;
00171 
00172    if (ast_lock_contexts()) {
00173       ast_log(LOG_ERROR, "Failed to lock contexts list\n");
00174       return -1;
00175    }
00176 
00177    for (c=ast_walk_contexts(NULL); c; c=ast_walk_contexts(c)) {
00178       struct ast_exten *e;
00179 
00180       if (!ast_lock_context(c)) {
00181          if (!strcmp(ast_get_context_name(c), chan->context)) {
00182             /* This is the matching context we want */
00183             int cur_priority = chan->priority + 1, level=1;
00184 
00185             for (e = find_matching_priority(c, chan->exten, cur_priority, chan->cid.cid_num); e; e = find_matching_priority(c, chan->exten, ++cur_priority, chan->cid.cid_num)) {
00186                if (!strcasecmp(ast_get_extension_app(e), "WHILE")) {
00187                   level++;
00188                } else if (!strcasecmp(ast_get_extension_app(e), "ENDWHILE")) {
00189                   level--;
00190                }
00191 
00192                if (level == 0) {
00193                   res = cur_priority;
00194                   break;
00195                }
00196             }
00197          }
00198          ast_unlock_context(c);
00199          if (res > 0) {
00200             break;
00201          }
00202       }
00203    }
00204    ast_unlock_contexts();
00205    return res;
00206 }
00207 
00208 static int _while_exec(struct ast_channel *chan, void *data, int end)
00209 {
00210    int res=0;
00211    struct localuser *u;
00212    char *while_pri = NULL;
00213    char *goto_str = NULL, *my_name = NULL;
00214    char *condition = NULL, *label = NULL;
00215    char varname[VAR_SIZE], end_varname[VAR_SIZE];
00216    const char *prefix = "WHILE";
00217    size_t size=0;
00218    int used_index_i = -1, x=0;
00219    char used_index[VAR_SIZE] = "0", new_index[VAR_SIZE] = "0";
00220    
00221    if (!chan) {
00222       /* huh ? */
00223       return -1;
00224    }
00225 
00226    LOCAL_USER_ADD(u);
00227 
00228    /* dont want run away loops if the chan isn't even up
00229       this is up for debate since it slows things down a tad ......
00230    */
00231    if (ast_waitfordigit(chan,1) < 0)
00232       ALL_DONE(u,-1);
00233 
00234 
00235    for (x=0;;x++) {
00236       if (get_index(chan, prefix, x)) {
00237          used_index_i = x;
00238       } else 
00239          break;
00240    }
00241    
00242    snprintf(used_index, VAR_SIZE, "%d", used_index_i);
00243    snprintf(new_index, VAR_SIZE, "%d", used_index_i + 1);
00244    
00245    if (!end) {
00246       condition = ast_strdupa((char *) data);
00247    }
00248 
00249    size = strlen(chan->context) + strlen(chan->exten) + 32;
00250    my_name = alloca(size);
00251    memset(my_name, 0, size);
00252    snprintf(my_name, size, "%s_%s_%d", chan->context, chan->exten, chan->priority);
00253    
00254    if (ast_strlen_zero(label)) {
00255       if (end) 
00256          label = used_index;
00257       else if (!(label = pbx_builtin_getvar_helper(chan, my_name))) {
00258          label = new_index;
00259          pbx_builtin_setvar_helper(chan, my_name, label);
00260       }
00261       
00262    }
00263    
00264    snprintf(varname, VAR_SIZE, "%s_%s", prefix, label);
00265    while_pri = pbx_builtin_getvar_helper(chan, varname);
00266    
00267    if ((while_pri = pbx_builtin_getvar_helper(chan, varname)) && !end) {
00268       snprintf(end_varname,VAR_SIZE,"END_%s",varname);
00269    }
00270    
00271 
00272    if (!end && !pbx_checkcondition(condition)) {
00273       /* Condition Met (clean up helper vars) */
00274       pbx_builtin_setvar_helper(chan, varname, NULL);
00275       pbx_builtin_setvar_helper(chan, my_name, NULL);
00276         snprintf(end_varname,VAR_SIZE,"END_%s",varname);
00277       if ((goto_str=pbx_builtin_getvar_helper(chan, end_varname))) {
00278          pbx_builtin_setvar_helper(chan, end_varname, NULL);
00279          ast_parseable_goto(chan, goto_str);
00280       } else {
00281          int pri = find_matching_endwhile(chan);
00282          if (pri > 0) {
00283             if (option_verbose > 2)
00284                ast_verbose(VERBOSE_PREFIX_3 "Jumping to priority %d\n", pri);
00285             chan->priority = pri;
00286          } else {
00287             ast_log(LOG_WARNING, "Couldn't find matching EndWhile? (While at %s@%s priority %d)\n", chan->context, chan->exten, chan->priority);
00288          }
00289       }
00290       ALL_DONE(u,res);
00291    }
00292 
00293    if (!end && !while_pri) {
00294       size = strlen(chan->context) + strlen(chan->exten) + 32;
00295       goto_str = alloca(size);
00296       memset(goto_str, 0, size);
00297       snprintf(goto_str, size, "%s|%s|%d", chan->context, chan->exten, chan->priority);
00298       pbx_builtin_setvar_helper(chan, varname, goto_str);
00299    } 
00300 
00301    else if (end && while_pri) {
00302       /* END of loop */
00303       snprintf(end_varname, VAR_SIZE, "END_%s", varname);
00304       if (! pbx_builtin_getvar_helper(chan, end_varname)) {
00305          size = strlen(chan->context) + strlen(chan->exten) + 32;
00306          goto_str = alloca(size);
00307          memset(goto_str, 0, size);
00308          snprintf(goto_str, size, "%s|%s|%d", chan->context, chan->exten, chan->priority+1);
00309          pbx_builtin_setvar_helper(chan, end_varname, goto_str);
00310       }
00311       ast_parseable_goto(chan, while_pri);
00312    }
00313    
00314 
00315 
00316 
00317    ALL_DONE(u, res);
00318 }
00319 
00320 static int while_start_exec(struct ast_channel *chan, void *data) {
00321    return _while_exec(chan, data, 0);
00322 }
00323 
00324 static int while_end_exec(struct ast_channel *chan, void *data) {
00325    return _while_exec(chan, data, 1);
00326 }
00327 
00328 
00329 int unload_module(void)
00330 {
00331    int res;
00332    
00333    res = ast_unregister_application(start_app);
00334    res |= ast_unregister_application(exec_app);
00335    res |= ast_unregister_application(stop_app);
00336 
00337    STANDARD_HANGUP_LOCALUSERS;
00338 
00339    return res;
00340 }
00341 
00342 int load_module(void)
00343 {
00344    int res;
00345 
00346    res = ast_register_application(start_app, while_start_exec, start_synopsis, start_desc);
00347    res |= ast_register_application(exec_app, execif_exec, exec_synopsis, exec_desc);
00348    res |= ast_register_application(stop_app, while_end_exec, stop_synopsis, stop_desc);
00349 
00350    return res;
00351 }
00352 
00353 char *description(void)
00354 {
00355    return tdesc;
00356 }
00357 
00358 int usecount(void)
00359 {
00360    int res;
00361    STANDARD_USECOUNT(res);
00362    return res;
00363 }
00364 
00365 char *key()
00366 {
00367    return ASTERISK_GPL_KEY;
00368 }
00369 

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