[vlc-devel] [vlc-commits] compat: replace aligned_alloc() rather than posix_memalign()
Steve Lhomme
robux4 at gmail.com
Tue Jun 20 12:05:49 CEST 2017
On Tue, Jun 20, 2017 at 11:53 AM, <remi at remlab.net> wrote:
> Repeating myself but this patch does not change the fallback logic, so it
> can't break anything.
>
> And to paraphrase other devs "I don't care" about non-ISO toolchains.
The fact on Windows the aligned malloc needs to be freed with an
aligned version of free() has nothing to do with the toolchain.
>
> Le 20 juin 2017 12:40:41 GMT+03:00, Steve Lhomme <robux4 at gmail.com> a écrit
> :
>>
>> On Tue, Jun 20, 2017 at 11:35 AM, Steve Lhomme <robux4 at gmail.com> wrote:
>>>
>>> On Tue, Jun 20, 2017 at 11:28 AM, <remi at remlab.net> wrote:
>>>>
>>>> The goal is to use aligned_alloc() instead of posix_memalign() since
>>>> the
>>>> earlier is required by ISO C and C++ (and slightly simpler to use).
>>>>
>>>> This patch only changes the behaviour on supported non-POSIX toolchains
>>>> by
>>>> removing the need for POSIX emulation code. If the toolchain is broken,
>>>> then
>>>> the fallback logic is unchanged: posix_memalign(), else memalign() else
>>>> screw-you.
>>>
>>>
>>> There is no posix_memalign() or memalign() on Windows. So right now
>>> VLC and libvlc cannot be used at all.
>>>
>>> Proper support requires using __mingw_aligned_malloc() or
>>> _aligned_malloc(). But that means using __mingw_aligned_free() and
>>> _aligned_free() as well.
>>
>>
>> For the record, calling free() instead of these aligned free functions
>> results in a crash.
>>
>>> Next time you may break the core, please submit patches for review
>>> first.
>>>
>>>> Le 20 juin 2017 12:07:38 GMT+03:00, Steve Lhomme <robux4 at gmail.com> a
>>>> écrit
>>>> :
>>>>>
>>>>>
>>>>> On Sat, Jun 17, 2017 at 2:35 PM, Rémi Denis-Courmont
>>>>> <git at videolan.org>
>>>>> wrote:
>>>>>>
>>>>>>
>>>>>> vlc | branch: master | Rémi Denis-Courmont <remi at remlab.net> | Sat
>>>>>> Jun
>>>>>> 17 15:27:16 2017 +0300| [34cd965645cb0246f3d74515bbd5e55367f7d884] |
>>>>>> committer: Rémi Denis-Courmont
>>>>>>
>>>>>> compat: replace aligned_alloc() rather than posix_memalign()
>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=34cd965645cb0246f3d74515bbd5e55367f7d884
>>>>>>
>>>>>>
>>>>>> ---
>>>>>>
>>>>>> compat/{posix_memalign.c => aligned_alloc.c} | 62
>>>>>> ++++++++++++++--------------
>>>>>> configure.ac | 4 +-
>>>>>> include/vlc_common.h | 8 +---
>>>>>> include/vlc_fixups.h | 6 +--
>>>>>> 4 files changed, 36 insertions(+), 44 deletions(-)
>>>>>>
>>>>>> diff --git a/compat/posix_memalign.c b/compat/aligned_alloc.c
>>>>>> similarity index 55%
>>>>>> rename from compat/posix_memalign.c
>>>>>> rename to compat/aligned_alloc.c
>>>>>> index 3c6ffdfe28..9a61c0010f 100644
>>>>>> --- a/compat/posix_memalign.c
>>>>>> +++ b/compat/aligned_alloc.c
>>>>>> @@ -1,7 +1,7 @@
>>>>>>
>>>>>>
>>>>>> /*****************************************************************************
>>>>>> - * posix_memalign.c: POSIX posix_memalign() replacement
>>>>>> + * aligned_alloc.c: C11 aligned_alloc() replacement
>>>>>>
>>>>>>
>>>>>> *****************************************************************************
>>>>>> - * Copyright © 2012 Rémi Denis-Courmont
>>>>>> + * Copyright © 2012, 2017 Rémi Denis-Courmont
>>>>>> *
>>>>>> * This program is free software; you can redistribute it and/or
>>>>>> modify
>>>>>> it
>>>>>> * under the terms of the GNU Lesser General Public License as
>>>>>> published by
>>>>>> @@ -22,46 +22,44 @@
>>>>>> # include <config.h>
>>>>>> #endif
>>>>>>
>>>>>> +#include <assert.h>
>>>>>> #include <stdlib.h>
>>>>>> #include <errno.h>
>>>>>> +#if !defined (HAVE_POSIX_MEMALIGN) && !defined (_WIN32) && !defined
>>>>>> (__APPLE__)
>>>>>> +# include <malloc.h>
>>>>>> +#endif
>>>>>>
>>>>>> -static int check_align (size_t align)
>>>>>> +void *aligned_alloc(size_t align, size_t size)
>>>>>> {
>>>>>> - for (size_t i = sizeof (void *); i != 0; i *= 2)
>>>>>> - if (align == i)
>>>>>> - return 0;
>>>>>> - return EINVAL;
>>>>>> -}
>>>>>> -
>>>>>> -#if !defined (_WIN32) && !defined (__APPLE__)
>>>>>> -#include <malloc.h>
>>>>>> + /* align must be a power of 2 */
>>>>>> + /* size must be a multiple of align */
>>>>>> + if ((align & (align - 1)) || (size & (align - 1)))
>>>>>> + {
>>>>>> + errno = EINVAL;
>>>>>> + return NULL;
>>>>>> + }
>>>>>>
>>>>>> -int posix_memalign (void **ptr, size_t align, size_t size)
>>>>>> -{
>>>>>> - if (check_align (align))
>>>>>> - return EINVAL;
>>>>>> +#ifdef HAVE_POSIX_MEMALIGN
>>>>>> + if (align < sizeof (void *)) /* POSIX does not allow small
>>>>>> alignment */
>>>>>> + align = sizeof (void *);
>>>>>>
>>>>>> - int saved_errno = errno;
>>>>>> - void *p = memalign (align, size);
>>>>>> - if (p == NULL)
>>>>>> + void *ptr;
>>>>>> + int err = posix_memalign(&ptr, align, size);
>>>>>> + if (err)
>>>>>> {
>>>>>> - errno = saved_errno;
>>>>>> - return ENOMEM;
>>>>>> + errno = err;
>>>>>> + ptr = NULL;
>>>>>> }
>>>>>> + return ptr;
>>>>>>
>>>>>> - *ptr = p;
>>>>>> - return 0;
>>>>>> -}
>>>>>> +#elif !defined (_WIN32) && !defined (__APPLE__)
>>>>>>
>>>>>> -#else
>>>>>> -
>>>>>> -int posix_memalign (void **ptr, size_t align, size_t size)
>>>>>> -{
>>>>>> - if (check_align (align))
>>>>>> - return EINVAL;
>>>>>> + return memalign(align, size);
>>>>>
>>>>>
>>>>>
>>>>> Is the goal that this code is never called for Windows and Apple OSes
>>>>> ? Because it worked and this function always return NULL.
>>>>>
>>>>>> - *ptr = NULL;
>>>>>> - return size ? ENOMEM : 0;
>>>>>> -}
>>>>>> +#else
>>>>>>
>>>>>> + if (size > 0)
>>>>>> + errno = ENOMEM;
>>>>>> + return NULL;
>>>>>> #endif
>>>>>> +}
>>>>>> diff --git a/configure.ac b/configure.ac
>>>>>> index b1883a18b7..67fc7deb1a 100644
>>>>>> --- a/configure.ac
>>>>>> +++ b/configure.ac
>>>>>> @@ -597,8 +597,8 @@ dnl Check for system libs needed
>>>>>> need_libc=false
>>>>>>
>>>>>> dnl Check for usual libc functions
>>>>>> -AC_CHECK_FUNCS([daemon fcntl flock fstatvfs fork getenv getpwuid_r
>>>>>> isatty lstat memalign mkostemp mmap open_memstream openat pread
>>>>>> posix_fadvise posix_madvise setlocale stricmp strnicmp strptime
>>>>>> tdestroy
>>>>>> uselocale])
>>>>>> -AC_REPLACE_FUNCS([atof atoll dirfd fdopendir ffsll flockfile fsync
>>>>>> getdelim getpid lldiv memrchr nrand48 poll posix_memalign recvmsg
>>>>>> rewind
>>>>>> sendmsg setenv strcasecmp strcasestr strdup strlcpy strndup strnlen
>>>>>> strnstr
>>>>>> strsep strtof strtok_r strtoll swab tfind timegm timespec_get
>>>>>> strverscmp
>>>>>> pathconf])
>>>>>> +AC_CHECK_FUNCS([daemon fcntl flock fstatvfs fork getenv getpwuid_r
>>>>>> isatty lstat memalign mkostemp mmap open_memstream openat pread
>>>>>> posix_fadvise posix_madvise posix_memalign setlocale stricmp strnicmp
>>>>>> strptime tdestroy uselocale])
>>>>>> +AC_REPLACE_FUNCS([aligned_alloc atof atoll dirfd fdopendir ffsll
>>>>>> flockfile fsync getdelim getpid lldiv memrchr nrand48 poll recvmsg
>>>>>> rewind
>>>>>> sendmsg setenv strcasecmp strcasestr strdup strlcpy strndup strnlen
>>>>>> strnstr
>>>>>> strsep strtof strtok_r strtoll swab tfind timegm timespec_get
>>>>>> strverscmp
>>>>>> pathconf])
>>>>>> AC_REPLACE_FUNCS([gettimeofday])
>>>>>> AC_CHECK_FUNC(fdatasync,,
>>>>>> [AC_DEFINE(fdatasync, fsync, [Alias fdatasync() to fsync() if
>>>>>> missing.])
>>>>>> diff --git a/include/vlc_common.h b/include/vlc_common.h
>>>>>> index e1cf885379..0bfb1b9b04 100644
>>>>>> --- a/include/vlc_common.h
>>>>>> +++ b/include/vlc_common.h
>>>>>> @@ -854,13 +854,7 @@ VLC_API bool vlc_ureduce( unsigned *, unsigned
>>>>>> *,
>>>>>> uint64_t, uint64_t, uint64_t )
>>>>>> # define vlc_memalign(align, size) (_aligned_malloc(size, align))
>>>>>> # define vlc_free(base) (_aligned_free(base))
>>>>>> #else
>>>>>> -static inline void *vlc_memalign(size_t align, size_t size)
>>>>>> -{
>>>>>> - void *base;
>>>>>> - if (unlikely(posix_memalign(&base, align, size)))
>>>>>> - base = NULL;
>>>>>> - return base;
>>>>>> -}
>>>>>> +# define vlc_memalign(align, size) aligned_alloc(align, size)
>>>>>> # define vlc_free(base) free(base)
>>>>>> #endif
>>>>>>
>>>>>> diff --git a/include/vlc_fixups.h b/include/vlc_fixups.h
>>>>>> index 8bfb76888f..44b8426f2c 100644
>>>>>> --- a/include/vlc_fixups.h
>>>>>> +++ b/include/vlc_fixups.h
>>>>>> @@ -88,7 +88,7 @@ typedef struct
>>>>>> # include <stdio.h> /* FILE */
>>>>>> #endif
>>>>>>
>>>>>> -#if !defined (HAVE_POSIX_MEMALIGN) || \
>>>>>> +#if !defined (HAVE_ALIGNED_ALLOC) || \
>>>>>> !defined (HAVE_MEMRCHR) || \
>>>>>> !defined (HAVE_STRLCPY) || \
>>>>>> !defined (HAVE_STRNDUP) || \
>>>>>> @@ -302,8 +302,8 @@ int setenv (const char *, const char *, int);
>>>>>> int unsetenv (const char *);
>>>>>> #endif
>>>>>>
>>>>>> -#ifndef HAVE_POSIX_MEMALIGN
>>>>>> -int posix_memalign (void **, size_t, size_t);
>>>>>> +#ifndef HAVE_ALIGNED_ALLOC
>>>>>> +void *aligned_alloc(size_t, size_t);
>>>>>> #endif
>>>>>>
>>>>>> #if defined(__native_client__) && defined(__cplusplus)
>>>>>>
>>>>>> ________________________________
>>>>>>
>>>>>>
>>>>>> vlc-commits mailing list
>>>>>> vlc-commits at videolan.org
>>>>>> https://mailman.videolan.org/listinfo/vlc-commits
>>>>>
>>>>>
>>>>> ________________________________
>>>>>
>>>>>
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>>>>
>>>>
>>>>
>>>> --
>>>> Envoyé de mon appareil Android avec Courriel K-9 Mail. Veuillez excuser
>>>> ma
>>>> brièveté.
>>>>
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>
> --
> Envoyé de mon appareil Android avec Courriel K-9 Mail. Veuillez excuser ma
> brièveté.
>
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