gmodule/gmodule-win32.c

   1 /* GMODULE - GLIB wrapper code for dynamic module loading
   2  * Copyright (C) 1998, 2000 Tim Janik
   3  *
   4  * Win32 GMODULE implementation
   5  * Copyright (C) 1998 Tor Lillqvist
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the
  19  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20  * Boston, MA 02111-1307, USA.
  21  */
  22
  23 /*
  24  * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
  25  * file for a list of people on the GLib Team.  See the ChangeLog
  26  * files for a list of changes.  These files are distributed with
  27  * GLib at ftp://ftp.gtk.org/pub/gtk/.
  28  */
  29
  30 /*
  31  * MT safe
  32  */
  33
  34 #include <stdio.h>
  35 #include <windows.h>
  36
  37 #include <tlhelp32.h>
  38
  39 #ifdef G_WITH_CYGWIN
  40 #include <sys/cygwin.h>
  41 #endif
  42
  43 static void
  44 set_error (void)
  45 {
  46   gchar *error = g_win32_error_message (GetLastError ());
  47
  48   g_module_set_error (error);
  49   g_free (error);
  50 }
  51
  52 /* --- functions --- */
  53 static gpointer
  54 _g_module_open (const gchar *file_name,
  55                 gboolean     bind_lazy)
  56 {
  57   HINSTANCE handle;
  58 #ifdef G_WITH_CYGWIN
  59   gchar tmp[MAX_PATH];
  60
  61   cygwin_conv_to_win32_path(file_name, tmp);
  62   file_name = tmp;
  63 #endif
  64
  65   handle = LoadLibrary (file_name);
  66   if (!handle)
  67     set_error ();
  68
  69   return handle;
  70 }
  71
  72 static gint dummy;
  73 static gpointer null_module_handle = &dummy;
  74
  75 static gpointer
  76 _g_module_self (void)
  77 {
  78   return null_module_handle;
  79 }
  80
  81 static void
  82 _g_module_close (gpointer handle,
  83                  gboolean is_unref)
  84 {
  85   if (handle != null_module_handle)
  86     if (!FreeLibrary (handle))
  87       set_error ();
  88 }
  89
  90 static gpointer
  91 find_in_any_module_using_toolhelp (const gchar *symbol_name)
  92 {
  93   typedef HANDLE (WINAPI *PFNCREATETOOLHELP32SNAPSHOT)(DWORD, DWORD);
  94   static PFNCREATETOOLHELP32SNAPSHOT pfnCreateToolhelp32Snapshot = NULL;
  95
  96   typedef BOOL (WINAPI *PFNMODULE32FIRST)(HANDLE, MODULEENTRY32*);
  97   static PFNMODULE32FIRST pfnModule32First= NULL;
  98
  99   typedef BOOL (WINAPI *PFNMODULE32NEXT)(HANDLE, MODULEENTRY32*);
 100   static PFNMODULE32NEXT pfnModule32Next = NULL;
 101
 102   static HMODULE kernel32;
 103
 104   HANDLE snapshot;
 105   MODULEENTRY32 me32;
 106
 107   gpointer p;
 108
 109   if (!pfnCreateToolhelp32Snapshot || !pfnModule32First || !pfnModule32Next)
 110     {
 111       if (!kernel32)
 112         if (!(kernel32 = GetModuleHandle ("kernel32.dll")))
 113           return NULL;
 114
 115       if (!(pfnCreateToolhelp32Snapshot = (PFNCREATETOOLHELP32SNAPSHOT) GetProcAddress (kernel32, "CreateToolhelp32Snapshot"))
 116           || !(pfnModule32First = (PFNMODULE32FIRST) GetProcAddress (kernel32, "Module32First"))
 117           || !(pfnModule32Next = (PFNMODULE32NEXT) GetProcAddress (kernel32, "Module32Next")))
 118         return NULL;
 119     }
 120
 121   if ((snapshot = (*pfnCreateToolhelp32Snapshot) (TH32CS_SNAPMODULE, 0)) == (HANDLE) -1)
 122     return NULL;
 123
 124   me32.dwSize = sizeof (me32);
 125   p = NULL;
 126   if ((*pfnModule32First) (snapshot, &me32))
 127     {
 128       do {
 129         if ((p = GetProcAddress (me32.hModule, symbol_name)) != NULL)
 130           break;
 131       } while ((*pfnModule32Next) (snapshot, &me32));
 132     }
 133
 134   CloseHandle (snapshot);
 135
 136   return p;
 137 }
 138
 139 static gpointer
 140 find_in_any_module_using_psapi (const gchar *symbol_name)
 141 {
 142   static HMODULE psapi = NULL;
 143
 144   typedef BOOL (WINAPI *PFNENUMPROCESSMODULES) (HANDLE, HMODULE *, DWORD, LPDWORD) ;
 145   static PFNENUMPROCESSMODULES pfnEnumProcessModules = NULL;
 146
 147   HMODULE *modules;
 148   HMODULE dummy;
 149   gint i, size;
 150   DWORD needed;
 151
 152   gpointer p;
 153
 154   if (!pfnEnumProcessModules)
 155     {
 156       if (!psapi)
 157         if ((psapi = LoadLibrary ("psapi.dll")) == NULL)
 158           return NULL;
 159
 160       if (!(pfnEnumProcessModules = (PFNENUMPROCESSMODULES) GetProcAddress (psapi, "EnumProcessModules")))
 161         return NULL;
 162     }
 163
 164   if (!(*pfnEnumProcessModules) (GetCurrentProcess (), &dummy,
 165                                  sizeof (HMODULE), &needed))
 166     return NULL;
 167
 168   size = needed + 10 * sizeof (HMODULE);
 169   modules = g_malloc (size);
 170
 171   if (!(*pfnEnumProcessModules) (GetCurrentProcess (), modules,
 172                                  size, &needed)
 173       || needed > size)
 174     {
 175       g_free (modules);
 176       return NULL;
 177     }
 178
 179   p = NULL;
 180   for (i = 0; i < needed / sizeof (HMODULE); i++)
 181     if ((p = GetProcAddress (modules[i], symbol_name)) != NULL)
 182       break;
 183
 184   g_free (modules);
 185
 186   return p;
 187 }
 188
 189 static gpointer
 190 find_in_any_module (const gchar *symbol_name)
 191 {
 192   gpointer result;
 193
 194   if ((result = find_in_any_module_using_toolhelp (symbol_name)) == NULL
 195       && (result = find_in_any_module_using_psapi (symbol_name)) == NULL)
 196     return NULL;
 197   else
 198     return result;
 199 }
 200
 201 static gpointer
 202 _g_module_symbol (gpointer     handle,
 203                   const gchar *symbol_name)
 204 {
 205   gpointer p;
 206
 207   if (handle == null_module_handle)
 208     {
 209       if ((p = GetProcAddress (GetModuleHandle (NULL), symbol_name)) == NULL)
 210         p = find_in_any_module (symbol_name);
 211     }
 212   else
 213     p = GetProcAddress (handle, symbol_name);
 214
 215   if (!p)
 216     set_error ();
 217
 218   return p;
 219 }
 220
 221 static gchar*
 222 _g_module_build_path (const gchar *directory,
 223                       const gchar *module_name)
 224 {
 225   gint k;
 226
 227   k = strlen (module_name);
 228
 229   if (directory && *directory)
 230     if (k > 4 && g_ascii_strcasecmp (module_name + k - 4, ".dll") == 0)
 231       return g_strconcat (directory, G_DIR_SEPARATOR_S, module_name, NULL);
 232     else if (strncmp (module_name, "lib", 3) == 0)
 233       return g_strconcat (directory, G_DIR_SEPARATOR_S, module_name, ".dll", NULL);
 234     else
 235       return g_strconcat (directory, G_DIR_SEPARATOR_S, "lib", module_name, ".dll", NULL);
 236   else if (k > 4 && g_ascii_strcasecmp (module_name + k - 4, ".dll") == 0)
 237     return g_strdup (module_name);
 238   else if (strncmp (module_name, "lib", 3) == 0)
 239     return g_strconcat (module_name, ".dll", NULL);
 240   else
 241     return g_strconcat ("lib", module_name, ".dll", NULL);
 242 }