Merge branch '896-variant-type-docs' into 'master'
[glib.git] / gmodule / gmodule-ar.c
blob3301c474f2aaae05e008807fa5af7bd69e417baf
1 /* GMODULE - GLIB wrapper code for dynamic module loading
2 * Copyright (C) 1998, 2000 Tim Janik
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18 /*
19 * MT safe
22 /* because we are compatible with archive format only since AIX 4.3 */
24 #define __AR_BIG__
26 #include "config.h"
28 #include <ar.h>
29 #include <stdlib.h>
31 #include <dlfcn.h>
33 /* --- functions --- */
34 static gchar*
35 fetch_dlerror (gboolean replace_null)
37 gchar *msg = dlerror ();
39 /* make sure we always return an error message != NULL, if
40 * expected to do so. */
42 if (!msg && replace_null)
43 return "unknown dl-error";
45 return msg;
48 static gchar* _g_module_get_member(const gchar* file_name)
50 gchar* member = NULL;
51 struct fl_hdr file_header;
52 struct ar_hdr ar_header;
53 long first_member;
54 long name_len;
55 int fd;
57 fd = open(file_name, O_RDONLY);
58 if (fd == -1)
59 return NULL;
61 if (read(fd, (void*)&file_header, FL_HSZ) != FL_HSZ)
62 goto exit;
64 if (strncmp(file_header.fl_magic, AIAMAGBIG, SAIAMAG) != 0)
65 goto exit;
67 /* read first archive file member header */
69 first_member = atol(file_header.fl_fstmoff);
71 if (lseek(fd, first_member, SEEK_SET) != first_member)
72 goto exit;
74 if (read(fd, (void*)&ar_header, AR_HSZ - 2) != AR_HSZ - 2)
75 goto exit;
77 /* read member name */
79 name_len = atol(ar_header.ar_namlen);
81 member = g_malloc(name_len+1);
82 if (!member)
83 goto exit;
85 if (read(fd, (void*)member, name_len) != name_len)
87 g_free(member);
88 member = NULL;
89 goto exit;
92 member[name_len] = 0;
94 exit:
95 close(fd);
97 return member;
100 static gpointer
101 _g_module_open (const gchar *file_name,
102 gboolean bind_lazy,
103 gboolean bind_local)
105 gpointer handle;
106 gchar* member;
107 gchar* full_name;
109 /* extract name of first member of archive */
111 member = _g_module_get_member (file_name);
112 if (member != NULL)
114 full_name = g_strconcat (file_name, "(", member, ")", NULL);
115 g_free (member);
117 else
118 full_name = g_strdup (file_name);
120 handle = dlopen (full_name,
121 (bind_local ? RTLD_LOCAL : RTLD_GLOBAL) | RTLD_MEMBER | (bind_lazy ? RTLD_LAZY : RTLD_NOW));
123 g_free (full_name);
125 if (!handle)
126 g_module_set_error (fetch_dlerror (TRUE));
128 return handle;
131 static gpointer
132 _g_module_self (void)
134 gpointer handle;
136 handle = dlopen (NULL, RTLD_GLOBAL | RTLD_LAZY);
137 if (!handle)
138 g_module_set_error (fetch_dlerror (TRUE));
140 return handle;
143 static void
144 _g_module_close (gpointer handle,
145 gboolean is_unref)
147 /* are there any systems out there that have dlopen()/dlclose()
148 * without a reference count implementation?
150 is_unref |= 1;
152 if (is_unref)
154 if (dlclose (handle) != 0)
155 g_module_set_error (fetch_dlerror (TRUE));
159 static gpointer
160 _g_module_symbol (gpointer handle,
161 const gchar *symbol_name)
163 gpointer p;
165 p = dlsym (handle, symbol_name);
166 if (!p)
167 g_module_set_error (fetch_dlerror (FALSE));
169 return p;
172 static gchar*
173 _g_module_build_path (const gchar *directory,
174 const gchar *module_name)
176 if (directory && *directory) {
177 if (strncmp (module_name, "lib", 3) == 0)
178 return g_strconcat (directory, "/", module_name, NULL);
179 else
180 return g_strconcat (directory, "/lib", module_name, "." G_MODULE_SUFFIX, NULL);
181 } else if (strncmp (module_name, "lib", 3) == 0)
182 return g_strdup (module_name);
183 else
184 return g_strconcat ("lib", module_name, "." G_MODULE_SUFFIX, NULL);