From bc5a53574c64eb51d2cbf31b26f4607e566eeaab Mon Sep 17 00:00:00 2001 From: Max Kellermann Date: Sat, 25 Oct 2014 20:42:50 +0200 Subject: [PATCH] decoder/faad: remove workaround for ancient libfaad2 ABI bug Many years ago, FAAD had a serious ABI bug: the NeAACDecInit() prototype in its header declared the "samplerate" parameter to be "unsigned long *", but internally, the function assumed it was "uint32_t *" instead. On 32 bit machines, that was no difference, but on 64 bit, this left one portion of the return value uninitialized; and worse, on big-endian, the wrong word was filled. This bug had to be worked around in MPD (commit 9c4e97a6). A few months later, the bug was fixed in the FAAD CVS in commit 1.117 on file libfaad/decoder.c; the commit message was: "Use public headers internally to prevent duplicate declarations" The commit message was too brief at best; the problem was not duplicate declarations, but a prototype mismatch. No mention of the bug fix in the ChangeLog. The MPD project never learned about this bug fix, and so MPD would always pass a "uin32_t *" dressed up as a "unsigned long *". Nearly 6 years later, it's about time to fix this second ABI problem. Let's kill the workaround! --- NEWS | 1 + m4/faad.m4 | 31 +--------------------- src/decoder/plugins/FaadDecoderPlugin.cxx | 12 ++------- src/decoder/plugins/Mp4v2DecoderPlugin.cxx | 12 ++------- 4 files changed, 6 insertions(+), 50 deletions(-) diff --git a/NEWS b/NEWS index e1497a0ed..2a6c5c439 100644 --- a/NEWS +++ b/NEWS @@ -1,5 +1,6 @@ ver 0.19.2 (not yet released) * decoder + - faad: remove workaround for ancient libfaad2 ABI bug - ffmpeg: recognize MIME type audio/aacp * output - fix memory leak after filter initialization error diff --git a/m4/faad.m4 b/m4/faad.m4 index 5ca520e79..9dcb1ccab 100644 --- a/m4/faad.m4 +++ b/m4/faad.m4 @@ -62,36 +62,7 @@ int main() { CPPFLAGS=$oldcppflags fi -if test x$enable_aac = xyes; then - oldcflags=$CFLAGS - oldlibs=$LIBS - oldcppflags=$CPPFLAGS - CFLAGS="$CFLAGS $FAAD_CFLAGS -Werror" - LIBS="$LIBS $FAAD_LIBS" - CPPFLAGS=$CFLAGS - - AC_MSG_CHECKING(for broken libfaad headers) - AC_COMPILE_IFELSE([AC_LANG_SOURCE([ -#include -#include -#include - -int main() { - unsigned char channels; - uint32_t sample_rate; - - NeAACDecInit2(NULL, NULL, 0, &sample_rate, &channels); - return 0; -} - ])], - [AC_MSG_RESULT(correct)], - [AC_MSG_RESULT(broken); - AC_DEFINE(HAVE_FAAD_LONG, 1, [Define if faad.h uses the broken "unsigned long" pointers])]) - - CFLAGS=$oldcflags - LIBS=$oldlibs - CPPFLAGS=$oldcppflags -else +if test x$enable_aac = xno; then FAAD_LIBS="" FAAD_CFLAGS="" fi diff --git a/src/decoder/plugins/FaadDecoderPlugin.cxx b/src/decoder/plugins/FaadDecoderPlugin.cxx index 793ab1011..add23aaa4 100644 --- a/src/decoder/plugins/FaadDecoderPlugin.cxx +++ b/src/decoder/plugins/FaadDecoderPlugin.cxx @@ -255,20 +255,12 @@ faad_decoder_init(NeAACDecHandle decoder, DecoderBuffer &buffer, } uint8_t channels; - uint32_t sample_rate; -#ifdef HAVE_FAAD_LONG - /* neaacdec.h declares all arguments as "unsigned long", but - internally expects uint32_t pointers. To avoid gcc - warnings, use this workaround. */ - unsigned long *sample_rate_p = (unsigned long *)(void *)&sample_rate; -#else - uint32_t *sample_rate_p = &sample_rate; -#endif + unsigned long sample_rate; long nbytes = NeAACDecInit(decoder, /* deconst hack, libfaad requires this */ const_cast(data.data), data.size, - sample_rate_p, &channels); + &sample_rate, &channels); if (nbytes < 0) { error.Set(faad_decoder_domain, "Not an AAC stream"); return false; diff --git a/src/decoder/plugins/Mp4v2DecoderPlugin.cxx b/src/decoder/plugins/Mp4v2DecoderPlugin.cxx index bf97763c5..34bccd243 100644 --- a/src/decoder/plugins/Mp4v2DecoderPlugin.cxx +++ b/src/decoder/plugins/Mp4v2DecoderPlugin.cxx @@ -39,15 +39,7 @@ static MP4TrackId mp4_get_aac_track(MP4FileHandle handle, NeAACDecHandle decoder, AudioFormat &audio_format, Error &error) { - uint32_t sample_rate; -#ifdef HAVE_FAAD_LONG - /* neaacdec.h declares all arguments as "unsigned long", but - internally expects uint32_t pointers. To avoid gcc - warnings, use this workaround. */ - unsigned long *sample_rate_r = (unsigned long*)&sample_rate; -#else - uint32_t *sample_rate_r = sample_rate; -#endif + unsigned long sample_rate; const MP4TrackId tracks = MP4GetNumberOfTracks(handle); @@ -80,7 +72,7 @@ mp4_get_aac_track(MP4FileHandle handle, NeAACDecHandle decoder, uint8_t channels; int32_t nbytes = NeAACDecInit(decoder, buff, buff_size, - sample_rate_r, &channels); + &sample_rate, &channels); free(buff);