loader/glibc.c

   1 /*
   2  * glibc threading support
   3  *
   4  * Copyright 2003 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 #include "wine/port.h"
  23
  24 #include <errno.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #ifdef HAVE_SYS_MMAN_H
  28 # include <sys/mman.h>
  29 #endif
  30 #ifdef HAVE_UNISTD_H
  31 # include <unistd.h>
  32 #endif
  33 #ifdef HAVE_PTHREAD_H
  34 # include <pthread.h>
  35 #endif
  36
  37 #include "wine/library.h"
  38
  39 /* malloc wrapper */
  40 static void *xmalloc( size_t size )
  41 {
  42     void *res;
  43
  44     if (!size) size = 1;
  45     if (!(res = malloc( size )))
  46     {
  47         fprintf( stderr, "wine: virtual memory exhausted\n" );
  48         exit(1);
  49     }
  50     return res;
  51 }
  52
  53 /* separate thread to check for NPTL and TLS features */
  54 static void *needs_pthread( void *arg )
  55 {
  56     pid_t tid = gettid();
  57     /* check for NPTL */
  58     if (tid != -1 && tid != getpid()) return (void *)1;
  59     /* check for TLS glibc */
  60     return (void *)(wine_get_gs() != 0);
  61 }
  62
  63 /* return the name of the Wine threading variant to use */
  64 static const char *get_threading(void)
  65 {
  66     pthread_t id;
  67     void *ret;
  68
  69     pthread_create( &id, NULL, needs_pthread, NULL );
  70     pthread_join( id, &ret );
  71     return ret ? "wine-pthread" : "wine-kthread";
  72 }
  73
  74 /* build a new full path from the specified path and name */
  75 static const char *build_new_path( const char *path, const char *name )
  76 {
  77     const char *p;
  78     char *ret;
  79
  80     if (!(p = strrchr( path, '/' ))) return name;
  81     p++;
  82     ret = xmalloc( (p - path) + strlen(name) + 1 );
  83     memcpy( ret, path, p - path );
  84     strcpy( ret + (p - path), name );
  85     return ret;
  86 }
  87
  88 static void check_vmsplit( void *stack )
  89 {
  90     if (stack < (void *)0x80000000)
  91     {
  92         /* if the stack is below 0x80000000, assume we can safely try a munmap there */
  93         if (munmap( (void *)0x80000000, 1 ) == -1 && errno == EINVAL)
  94             fprintf( stderr,
  95                      "Warning: memory above 0x80000000 doesn't seem to be accessible.\n"
  96                      "Wine requires a 3G/1G user/kernel memory split to work properly.\n" );
  97     }
  98 }
  99
 100 /**********************************************************************
 101  *           main
 102  */
 103 int main( int argc, char *argv[] )
 104 {
 105     const char *loader = getenv( "WINELOADER" );
 106     const char *threads = get_threading();
 107     const char *new_argv0 = build_new_path( argv[0], threads );
 108
 109     wine_init_argv0_path( new_argv0 );
 110
 111     if (loader)
 112     {
 113         /* update WINELOADER with the new name */
 114         const char *new_name = build_new_path( loader, threads );
 115         char *new_loader = xmalloc( sizeof("WINELOADER=") + strlen(new_name) );
 116         strcpy( new_loader, "WINELOADER=" );
 117         strcat( new_loader, new_name );
 118         putenv( new_loader );
 119         loader = new_name;
 120     }
 121
 122     check_vmsplit( &argc );
 123     wine_exec_wine_binary( NULL, argv, loader );
 124     fprintf( stderr, "wine: could not exec %s\n", threads );
 125     exit(1);
 126 }