[vlc-devel] [PATCH 2/2] Work around the lack of dirfd()

[Rafaël Carré]

Le 2012-02-28 05:37, Brad Smith a écrit :
> On Tue, Feb 28, 2012 at 09:37:28AM +0000, Maciej (Matchek) Blizi??ski wrote:
>> 2012/2/28 Brad Smith <brad at comstyle.com>:
>>> Solaris does not have posix_memalign(). This will help..
>>
>> I was thinking that a better approach would be to test for
>> posix_memalign and define it when missing. What do you think?
> 
> VLC already uses macros and the header is already more or less
> ready to deal with Solaris. It just needs a bit of tweaking.
> Here is a better diff.. the OS's that use memalign() should
> not be a hardcoded list and for OS's where both exist posix_memalign()
> should be preferred..
> 
> 
> diff --git a/configure.ac b/configure.ac
> index 6d2562c..51cb16c 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -490,7 +490,7 @@ need_libc=false
>  
>  dnl Check for usual libc functions
>  AC_CHECK_DECLS([nanosleep],,,[#include <time.h>])
> -AC_CHECK_FUNCS([daemon fcntl fstatvfs fork getenv getpwuid_r if_nameindex if_nametoindex isatty lstat memalign mmap openat pread posix_fadvise posix_madvise setlocale stricmp strnicmp strptime uselocale])
> +AC_CHECK_FUNCS([daemon fcntl fstatvfs fork getenv getpwuid_r if_nameindex if_nametoindex isatty lstat posix_memalign memalign mmap openat pread posix_fadvise posix_madvise setlocale stricmp strnicmp strptime uselocale])
>  AC_REPLACE_FUNCS([atof atoll dirfd fdopendir flockfile fsync getdelim getpid gmtime_r inet_pton lldiv localtime_r nrand48 poll rewind setenv strcasecmp strcasestr strdup strlcpy strncasecmp strndup strnlen strsep strtof strtok_r strtoll swab tdestroy strverscmp])
>  AC_CHECK_FUNCS(fdatasync,,
>    [AC_DEFINE(fdatasync, fsync, [Alias fdatasync() to fsync() if missing.])
> diff --git a/include/vlc_common.h b/include/vlc_common.h
> index 545b1cd..0a308c1 100644
> --- a/include/vlc_common.h
> +++ b/include/vlc_common.h
> @@ -904,10 +904,7 @@ static void vlc_free(void *ptr)
>      if (ptr)
>          free((char*)ptr - ((char*)ptr)[-1]);
>  }
> -#elif defined(__ANDROID__)
> -# define vlc_memalign(align, size) memalign(align, size)
> -# define vlc_free(base) free(base)
> -#else
> +#elif defined(HAVE_POSIX_MEMALIGN)

IIRC some android versions have posix_memalign but we don't want to use
it to maintain backward compatibility, or it maybe that it's present in
the SDK but not on the device libc

>  static inline void *vlc_memalign(size_t align, size_t size)
>  {
>      void *base;
> @@ -916,6 +913,9 @@ static inline void *vlc_memalign(size_t align, size_t size)
>      return base;
>  }
>  # define vlc_free(base) free(base)
> +#elif defined(HAVE_MEMALIGN)
> +# define vlc_memalign(align, size) memalign(align, size)
> +# define vlc_free(base) free(base)
>  #endif
>  
>  VLC_API void vlc_tdestroy( void *, void (*)(void *) );
>