Re: Alexandre Julliard : libwine: Ignore libraries that are of the wrong 32/ 64 class.

[Ken Thomases]

Hi Alexandre,

It seems this would fail to ignore a fat Mach-O library that doesn't  
include the right 32/64 class.  For example, a fat i386/ppc library  
when running 64-bit.

A fat library starts with the struct fat_header defined in /usr/ 
include/mach-o/fat.h, followed by a number of struct fat_arch-es.  Its  
magic is 0xcafebabe in big-endian order.

This would also fail to ignore a PowerPC-only library because the  
magic would be big-endian, but I doubt we care about that.

-Ken

On Aug 11, 2009, at 10:47 AM, Alexandre Julliard wrote:
> Module: wine
> Branch: master
> Commit: 99538272d5b4ffc852f950dd3447a7072d6316ff
> URL:    http://source.winehq.org/git/wine.git/?a=commit;h=99538272d5b4ffc852f950dd34...
>
> Author: Alexandre Julliard 
> Date:   Tue Aug 11 17:29:07 2009 +0200
>
> libwine: Ignore libraries that are of the wrong 32/64 class.
>
> libs/wine/loader.c |   46 +++++++++++++++++++++++++++++++++++++++++++ 
> +--
> 1 files changed, 44 insertions(+), 2 deletions(-)
>
> diff --git a/libs/wine/loader.c b/libs/wine/loader.c
> index d10a6e0..37c603e 100644
> --- a/libs/wine/loader.c
> +++ b/libs/wine/loader.c
> @@ -147,12 +147,54 @@ static void build_dll_path(void)
>     }
> }
>
> +/* check if the library is the correct architecture */
> +/* only returns false for a valid library of the wrong arch */
> +static int check_library_arch( int fd )
> +{
> +#ifdef __APPLE__
> - struct  /* Mach-O header */
> - {
> -
>    unsigned int magic;
> -
>    unsigned int cputype;
> - } header;
> -
> - if (read( fd, &header, sizeof(header) ) != sizeof(header))
>
> return 1;
> - if (header.magic != 0xfeedface) return 1;
> - if (sizeof(void *) == sizeof(int)) return !(header.cputype >>
>
> 24);
> - else return (header.cputype >> 24) == 1; /* CPU_ARCH_ABI64 */
>
> +#else
> - struct  /* ELF header */
> - {
> -
>    unsigned char magic[4];
> -
>    unsigned char class;
> -
>    unsigned char data;
> -
>    unsigned char version;
> - } header;
> -
> - if (read( fd, &header, sizeof(header) ) != sizeof(header))
>
> return 1;
> - if (memcmp( header.magic, "\177ELF", 4 )) return 1;
> - if (header.version != 1 /* EV_CURRENT */) return 1;
>
> +#ifdef WORDS_BIGENDIAN
> - if (header.data != 2 /* ELFDATA2MSB */) return 1;
>
> +#else
> - if (header.data != 1 /* ELFDATA2LSB */) return 1;
>
> +#endif
> - if (sizeof(void *) == sizeof(int)) return header.class == 1; /*
>
> ELFCLASS32 */
> - else return header.class == 2; /* ELFCLASS64 */
>
> +#endif
> +}
> -
>
> /* check if a given file can be opened */
> static inline int file_exists( const char *name )
> {
> - int ret = 0;
> int fd = open( name, O_RDONLY );
> - if (fd != -1) close( fd );
> - return (fd != -1);
> - if (fd != -1)
> - {
> -
>    ret = check_library_arch( fd );
> -
>    close( fd );
> - }
> - return ret;
>
> }
>
> static inline char *prepend( char *buffer, const char *str, size_t  
> len )