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_SYS_RESOURCE_H
  31 # include <sys/resource.h>
  32 #endif
  33 #ifdef HAVE_UNISTD_H
  34 # include <unistd.h>
  35 #endif
  36 #ifdef HAVE_PTHREAD_H
  37 # include <pthread.h>
  38 #endif
  39
  40 #include "wine/library.h"
  41
  42 /* malloc wrapper */
  43 static void *xmalloc( size_t size )
  44 {
  45     void *res;
  46
  47     if (!size) size = 1;
  48     if (!(res = malloc( size )))
  49     {
  50         fprintf( stderr, "wine: virtual memory exhausted\n" );
  51         exit(1);
  52     }
  53     return res;
  54 }
  55
  56 /* separate thread to check for NPTL and TLS features */
  57 static void *needs_pthread( void *arg )
  58 {
  59     pid_t tid = gettid();
  60     /* check for NPTL */
  61     if (tid != -1 && tid != getpid()) return (void *)1;
  62     /* check for TLS glibc */
  63     return (void *)(wine_get_gs() != 0);
  64 }
  65
  66 /* return the name of the Wine threading variant to use */
  67 static const char *get_threading(void)
  68 {
  69     pthread_t id;
  70     void *ret;
  71
  72     pthread_create( &id, NULL, needs_pthread, NULL );
  73     pthread_join( id, &ret );
  74     return ret ? "wine-pthread" : "wine-kthread";
  75 }
  76
  77 /* build a new full path from the specified path and name */
  78 static const char *build_new_path( const char *path, const char *name )
  79 {
  80     const char *p;
  81     char *ret;
  82
  83     if (!(p = strrchr( path, '/' ))) return name;
  84     p++;
  85     ret = xmalloc( (p - path) + strlen(name) + 1 );
  86     memcpy( ret, path, p - path );
  87     strcpy( ret + (p - path), name );
  88     return ret;
  89 }
  90
  91 static void check_vmsplit( void *stack )
  92 {
  93     if (stack < (void *)0x80000000)
  94     {
  95         /* if the stack is below 0x80000000, assume we can safely try a munmap there */
  96         if (munmap( (void *)0x80000000, 1 ) == -1 && errno == EINVAL)
  97             fprintf( stderr,
  98                      "Warning: memory above 0x80000000 doesn't seem to be accessible.\n"
  99                      "Wine requires a 3G/1G user/kernel memory split to work properly.\n" );
 100     }
 101 }
 102
 103 static void set_max_limit( int limit )
 104 {
 105     struct rlimit rlimit;
 106
 107     if (!getrlimit( limit, &rlimit ))
 108     {
 109         rlimit.rlim_cur = rlimit.rlim_max;
 110         setrlimit( limit, &rlimit );
 111     }
 112 }
 113
 114
 115 /**********************************************************************
 116  *           main
 117  */
 118 int main( int argc, char *argv[] )
 119 {
 120     const char *loader = getenv( "WINELOADER" );
 121     const char *threads = get_threading();
 122     const char *new_argv0 = build_new_path( argv[0], threads );
 123
 124     wine_init_argv0_path( new_argv0 );
 125
 126     /* set the address space limit before starting the preloader */
 127     set_max_limit( RLIMIT_AS );
 128
 129     if (loader)
 130     {
 131         /* update WINELOADER with the new name */
 132         const char *new_name = build_new_path( loader, threads );
 133         char *new_loader = xmalloc( sizeof("WINELOADER=") + strlen(new_name) );
 134         strcpy( new_loader, "WINELOADER=" );
 135         strcat( new_loader, new_name );
 136         putenv( new_loader );
 137         loader = new_name;
 138     }
 139
 140     check_vmsplit( &argc );
 141     wine_exec_wine_binary( NULL, argv, loader );
 142     fprintf( stderr, "wine: could not exec %s\n", threads );
 143     exit(1);
 144 }