loader/main.c

   1 /*
   2  * Emulator initialisation code
   3  *
   4  * Copyright 2000 Alexandre Julliard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 #include "config.h"
  22
  23 #include <fcntl.h>
  24 #include <pthread.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <sys/types.h>
  29 #include <sys/stat.h>
  30 #include <unistd.h>
  31 #include <dlfcn.h>
  32 #include <limits.h>
  33 #ifdef HAVE_SYS_SYSCTL_H
  34 # include <sys/sysctl.h>
  35 #endif
  36
  37 #include "main.h"
  38
  39 extern char **environ;
  40
  41 /* the preloader will set this variable */
  42 const __attribute((visibility("default"))) struct wine_preload_info *wine_main_preload_info = NULL;
  43
  44 /* canonicalize path and return its directory name */
  45 static char *realpath_dirname( const char *name )
  46 {
  47     char *p, *fullpath = realpath( name, NULL );
  48
  49     if (fullpath)
  50     {
  51         p = strrchr( fullpath, '/' );
  52         if (p == fullpath) p++;
  53         if (p) *p = 0;
  54     }
  55     return fullpath;
  56 }
  57
  58 /* if string ends with tail, remove it */
  59 static char *remove_tail( const char *str, const char *tail )
  60 {
  61     size_t len = strlen( str );
  62     size_t tail_len = strlen( tail );
  63     char *ret;
  64
  65     if (len < tail_len) return NULL;
  66     if (strcmp( str + len - tail_len, tail )) return NULL;
  67     ret = malloc( len - tail_len + 1 );
  68     memcpy( ret, str, len - tail_len );
  69     ret[len - tail_len] = 0;
  70     return ret;
  71 }
  72
  73 /* build a path from the specified dir and name */
  74 static char *build_path( const char *dir, const char *name )
  75 {
  76     size_t len = strlen( dir );
  77     char *ret = malloc( len + strlen( name ) + 2 );
  78
  79     memcpy( ret, dir, len );
  80     if (len && ret[len - 1] != '/') ret[len++] = '/';
  81     strcpy( ret + len, name );
  82     return ret;
  83 }
  84
  85 static const char *get_self_exe( char *argv0 )
  86 {
  87 #if defined(__linux__) || defined(__FreeBSD_kernel__) || defined(__NetBSD__)
  88     return "/proc/self/exe";
  89 #elif defined (__FreeBSD__) || defined(__DragonFly__)
  90     static int pathname[] = { CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1 };
  91     size_t path_size = PATH_MAX;
  92     char *path = malloc( path_size );
  93     if (path && !sysctl( pathname, sizeof(pathname)/sizeof(pathname[0]), path, &path_size, NULL, 0 ))
  94         return path;
  95     free( path );
  96 #endif
  97
  98     if (!strchr( argv0, '/' )) /* search in PATH */
  99     {
 100         char *p, *path = getenv( "PATH" );
 101
 102         if (!path || !(path = strdup(path))) return NULL;
 103         for (p = strtok( path, ":" ); p; p = strtok( NULL, ":" ))
 104         {
 105             char *name = build_path( p, argv0 );
 106             if (!access( name, X_OK ))
 107             {
 108                 free( path );
 109                 return name;
 110             }
 111             free( name );
 112         }
 113         free( path );
 114         return NULL;
 115     }
 116     return argv0;
 117 }
 118
 119 static void *try_dlopen( const char *dir, const char *name )
 120 {
 121     char *path = build_path( dir, name );
 122     void *handle = dlopen( path, RTLD_NOW );
 123     free( path );
 124     return handle;
 125 }
 126
 127 static void *load_ntdll( char *argv0 )
 128 {
 129 #ifdef __i386__
 130 #define SO_DIR "i386-unix/"
 131 #elif defined(__x86_64__)
 132 #define SO_DIR "x86_64-unix/"
 133 #elif defined(__arm__)
 134 #define SO_DIR "arm-unix/"
 135 #elif defined(__aarch64__)
 136 #define SO_DIR "aarch64-unix/"
 137 #else
 138 #define SO_DIR ""
 139 #endif
 140     const char *self = get_self_exe( argv0 );
 141     char *path, *p;
 142     void *handle = NULL;
 143
 144     if (self && ((path = realpath_dirname( self ))))
 145     {
 146         if ((p = remove_tail( path, "/loader" )))
 147         {
 148             handle = try_dlopen( p, "dlls/ntdll/ntdll.so" );
 149             free( p );
 150         }
 151         else handle = try_dlopen( path, BIN_TO_DLLDIR "/" SO_DIR "ntdll.so" );
 152         free( path );
 153     }
 154
 155     if (!handle && (path = getenv( "WINEDLLPATH" )))
 156     {
 157         path = strdup( path );
 158         for (p = strtok( path, ":" ); p; p = strtok( NULL, ":" ))
 159         {
 160             handle = try_dlopen( p, SO_DIR "ntdll.so" );
 161             if (!handle) handle = try_dlopen( p, "ntdll.so" );
 162             if (handle) break;
 163         }
 164         free( path );
 165     }
 166
 167     if (!handle && !self) handle = try_dlopen( DLLDIR, SO_DIR "ntdll.so" );
 168
 169     return handle;
 170 }
 171
 172
 173 /**********************************************************************
 174  *           main
 175  */
 176 int main( int argc, char *argv[] )
 177 {
 178     void *handle;
 179
 180     if ((handle = load_ntdll( argv[0] )))
 181     {
 182         void (*init_func)(int, char **, char **) = dlsym( handle, "__wine_main" );
 183         if (init_func) init_func( argc, argv, environ );
 184         fprintf( stderr, "wine: __wine_main function not found in ntdll.so\n" );
 185         exit(1);
 186     }
 187
 188     fprintf( stderr, "wine: could not load ntdll.so: %s\n", dlerror() );
 189     pthread_detach( pthread_self() );  /* force importing libpthread for OpenGL */
 190     exit(1);
 191 }