1 /*
2  *  dl_loader.c
3  *
4  *  Copyright (C) Thomas Oestreich - June 2001
5  *
6  *  This file is part of transcode, a video stream processing tool
7  *
8  *  transcode is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License as published by
10  *  the Free Software Foundation; either version 2, or (at your option)
11  *  any later version.
12  *
13  *  transcode is distributed in the hope that it will be useful,
14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *  GNU General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License
19  *  along with GNU Make; see the file COPYING.  If not, write to
20  *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
21  *
22  */
23 #ifdef HAVE_CONFIG_H
24 #include "config.h"
25 #endif
26 
27 #ifdef HAVE_DLFCN_H
28 #include <dlfcn.h>
29 #else
30 # ifdef OS_DARWIN
31 #  include "libdldarwin/dlfcn.h"
32 # endif
33 #endif
34 
35 #include "transcode.h"
36 #include "dl_loader.h"
37 
38 const char *mod_path = MOD_PATH;
39 
40 char module[TC_BUF_MAX];
41 
42 int (*TCV_export)(int opt, void *para1, void *para2);
43 int (*TCA_export)(int opt, void *para1, void *para2);
44 int (*TCV_import)(int opt, void *para1, void *para2);
45 int (*TCA_import)(int opt, void *para1, void *para2);
46 
watch_export_module(const char * s,int opt,transfer_t * para)47 static void watch_export_module(const char *s, int opt, transfer_t *para)
48 {
49     tc_log_msg(__FILE__, "module=%s [option=%02d, flag=%d]", s, opt, ((para==NULL)? -1:para->flag));
50 }
51 
watch_import_module(const char * s,int opt,transfer_t * para)52 static void watch_import_module(const char *s, int opt, transfer_t *para)
53 {
54     tc_log_msg(__FILE__, "module=%s [option=%02d, flag=%d]", s, opt, ((para==NULL)? -1:para->flag));
55     fflush(stdout);
56 }
57 
tcv_export(int opt,void * para1,void * para2)58 int tcv_export(int opt, void *para1, void *para2)
59 {
60 
61   int ret;
62 
63   if(verbose & TC_WATCH)
64     watch_export_module("tcv_export", opt, (transfer_t*) para1);
65 
66   ret = TCV_export(opt, para1, para2);
67 
68   if(ret==TC_EXPORT_ERROR && (verbose & TC_DEBUG))
69     tc_log_msg(__FILE__, "video export module error");
70 
71   if(ret==TC_EXPORT_UNKNOWN && (verbose & TC_DEBUG))
72     tc_log_msg(__FILE__, "option %d unsupported by video export module", opt);
73 
74   return(ret);
75 }
76 
tca_export(int opt,void * para1,void * para2)77 int tca_export(int opt, void *para1, void *para2)
78 {
79 
80   int ret;
81 
82   if(verbose & TC_WATCH)
83     watch_export_module("tca_export", opt, (transfer_t*) para1);
84 
85   ret = TCA_export(opt, para1, para2);
86 
87   if(ret==TC_EXPORT_ERROR && (verbose & TC_DEBUG))
88     tc_log_msg(__FILE__, "audio export module error");
89 
90   if(ret==TC_EXPORT_UNKNOWN && (verbose & TC_DEBUG))
91     tc_log_msg(__FILE__, "option %d unsupported by audio export module", opt);
92 
93   return(ret);
94 }
95 
tcv_import(int opt,void * para1,void * para2)96 int tcv_import(int opt, void *para1, void *para2)
97 {
98 
99   int ret;
100 
101   if(verbose & TC_WATCH)
102     watch_import_module("tcv_import", opt, (transfer_t*) para1);
103 
104   ret = TCV_import(opt, para1, para2);
105 
106   if(ret==TC_IMPORT_ERROR && (verbose & TC_DEBUG))
107     tc_log_msg(__FILE__, "video import module error");
108 
109   if(ret==TC_IMPORT_UNKNOWN && (verbose & TC_DEBUG))
110     tc_log_msg(__FILE__, "option %d unsupported by video import module", opt);
111 
112   return(ret);
113 }
114 
tca_import(int opt,void * para1,void * para2)115 int tca_import(int opt, void *para1, void *para2)
116 {
117   int ret;
118 
119   if(verbose & TC_WATCH)
120     watch_import_module("tca_import", opt, (transfer_t*) para1);
121 
122   ret = TCA_import(opt, para1, para2);
123 
124   if(ret==TC_IMPORT_ERROR && (verbose & TC_DEBUG))
125     tc_log_msg(__FILE__, "audio import module error");
126 
127   if(ret==TC_IMPORT_UNKNOWN && (verbose & TC_DEBUG))
128     tc_log_msg(__FILE__, "option %d unsupported by audio import module", opt);
129 
130   return(ret);
131 }
132 
133 
load_module(const char * mod_name,int mode)134 void *load_module(const char *mod_name, int mode)
135 {
136   const char *error;
137   void *handle;
138 
139   if(mode & TC_EXPORT) {
140 
141     tc_snprintf(module, sizeof(module), "%s/export_%s.so", ((mod_path==NULL)? TC_DEFAULT_MOD_PATH:mod_path), mod_name);
142 
143     if(verbose & TC_DEBUG)
144       tc_log_msg(__FILE__, "loading %s export module %s", ((mode & TC_VIDEO)? "video": "audio"), module);
145 
146     handle = dlopen(module, RTLD_GLOBAL| RTLD_LAZY);
147 
148     if (!handle) {
149       error=dlerror();
150       tc_warn("%s", error);
151       tc_warn("(%s) loading \"%s\" failed", __FILE__, module);
152       return(NULL);
153     }
154 
155     if(mode & TC_VIDEO) {
156       TCV_export = dlsym(handle, "tc_export");
157       error = dlerror();
158       if (error != NULL)  {
159 	tc_warn("%s", error);
160 	return(NULL);
161       }
162     }
163 
164     if(mode & TC_AUDIO) {
165       TCA_export = dlsym(handle, "tc_export");
166       error = dlerror();
167       if (error != NULL)  {
168 	tc_warn("%s", error);
169 	return(NULL);
170       }
171     }
172 
173     return(handle);
174   }
175 
176 
177   if(mode & TC_IMPORT) {
178 
179     tc_snprintf(module, sizeof(module), "%s/import_%s.so", ((mod_path==NULL)? TC_DEFAULT_MOD_PATH:mod_path), mod_name);
180 
181     if(verbose & TC_DEBUG)
182       tc_log_msg(__FILE__, "loading %s import module %s", ((mode & TC_VIDEO)? "video": "audio"), module);
183 
184     handle = dlopen(module, RTLD_GLOBAL| RTLD_LAZY);
185 
186     if (!handle) {
187       error = dlerror();
188       tc_warn("%s", error);
189       return(NULL);
190     }
191 
192     if(mode & TC_VIDEO) {
193       TCV_import = dlsym(handle, "tc_import");
194       if ((error = dlerror()) != NULL)  {
195 	tc_warn("%s", error);
196 	return(NULL);
197       }
198     }
199 
200 
201     if(mode & TC_AUDIO) {
202       TCA_import = dlsym(handle, "tc_import");
203       if ((error = dlerror()) != NULL)  {
204 	tc_warn("%s", error);
205 	return(NULL);
206       }
207     }
208 
209     return(handle);
210   }
211 
212   // wrong mode?
213   return(NULL);
214 }
215 
unload_module(void * handle)216 void unload_module(void *handle)
217 {
218   if (dlclose(handle) != 0) {
219       perror("unloading module");
220   }
221   handle=NULL;
222 }
223 
224