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* random_seed: Improve behaviour with small timer increments with high ↵Martin Storsjö2025-02-131-0/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | precision timers On a Zen 5, on Ubuntu 24.04 (with CLOCKS_PER_SEC 1000000), the value of clock() in this loop increments by 0 most of the time, and when it does increment, it usually increments by 1 compared to the previous round. Due to the "last_t + 2*last_td + (CLOCKS_PER_SEC > 1000) >= t" expression, we only manage to take one step forward in this loop (incrementing i) if clock() increments by 2, while it incremented by 0 in the previous iteration (last_td). This is similar to the change done in c4152fc42e480c41efb7f761b1bbe5f0bc43d5bc, to speed it up on systems with very small CLOCKS_PER_SEC. However in this case, CLOCKS_PER_SEC is still very large, but the machine is fast enough to hit every clock increment repeatedly. For this case, use the number of repetitions of each timer value as entropy source; require a change in the number of repetitions in order to proceed to the next buffer index. This helps the fate-random-seed test to actually terminate within a reasonable time on such a system (where it previously could hang, running for many minutes). Signed-off-by: Martin Storsjö <martin@martin.st>
* random_seed: Reorder if clauses for gathering entropyMartin Storsjö2025-02-131-8/+11
| | | | | | | | Make it easier to add more cases. This should be a pure refactoring, with no functional changes. Signed-off-by: Martin Storsjö <martin@martin.st>
* avutil/random_seed: Avoid dead returnsMichael Niedermayer2024-05-281-3/+3
| | | | | | | Fixes: CID1538296 Structurally dead code Sponsored-by: Sovereign Tech Fund Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
* avutil/random_seed: turn off buffering when reading from randomMarton Balint2023-07-161-0/+1
| | | | Signed-off-by: Marton Balint <cus@passwd.hu>
* avutil: fix build failure on osx 10.4Pavel Koshevoy2023-07-081-1/+1
| | | | | | | | | | | libavutil/random_seed.c calls arc4random_buf which is not available on OSX 10.4 Tiger, but the configuration script tests for arc4random which is available. Fix the configuration test to match the actual API used. Co-authored-by: James Almer <jamrial@gmail.com> Signed-off-by: James Almer <jamrial@gmail.com>
* avutil/random_seed: add support for gcrypt and OpenSSL as source of randomnessJames Almer2023-07-061-0/+16
| | | | | Reviewed-by: Anton Khirnov <anton@khirnov.net> Signed-off-by: James Almer <jamrial@gmail.com>
* avutil/random_seed: add av_random_bytes()James Almer2023-07-051-11/+22
| | | | | | | Uses the existing code for av_get_random_seed() to return a buffer with cryptographically secure random data, or an error if none could be generated. Signed-off-by: James Almer <jamrial@gmail.com>
* avutil/random_seed: use fread() in read_random()James Almer2023-07-051-11/+12
| | | | | | | This ensures the requested amount of bytes is read. Also remove /dev/random as it's no longer necessary. Signed-off-by: James Almer <jamrial@gmail.com>
* avutil/internal: Move avpriv-file API to a header of its ownAndreas Rheinhardt2022-09-031-0/+1
| | | | | | | It is not used by the large majority of files that include lavu/internal.h. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
* avutil/random_seed: use bcrypt instead of the old wincrypt APISteve Lhomme2018-04-141-9/+10
| | | | | | | | Remove the wincrypt API calls since we don't support XP anymore and bcrypt is available since Vista, even on Windows Store builds. Reviewed-by: Michael Niedermayer <michael@niedermayer.cc> Signed-off-by: James Almer <jamrial@gmail.com>
* Merge commit '7ac092d05de487d088bc96ab4a7bd6207fbfa98c'James Almer2017-11-111-2/+2
|\ | | | | | | | | | | | | * commit '7ac092d05de487d088bc96ab4a7bd6207fbfa98c': build: CryptGenRandom --> wincrypt, it is a better name Merged-by: James Almer <jamrial@gmail.com>
| * build: CryptGenRandom --> wincrypt, it is a better nameDiego Biurrun2017-10-121-2/+2
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| * cosmetics: Fix spelling mistakesVittorio Giovara2016-05-041-1/+1
| | | | | | | | Signed-off-by: Diego Biurrun <diego@biurrun.de>
* | libavutil/random_seed: Ensure that get_generic_seed() spends at least 1/32 ↵Michael Niedermayer2016-12-311-2/+6
| | | | | | | | | | | | | | | | sec gathering entropy This may fix the failures on windows Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
* | avutil/random_seed: Reduce the time needed on systems with very low ↵Michael Niedermayer2016-12-241-1/+1
| | | | | | | | | | | | | | | | | | precission clock() This should fix issues on BSD CLOCKS_PER_SEC is 128 on BSD while SUSv2 requires it to be a million Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
* | avutil/random_seed: Improve get_generic_seed() with higher precission clock()Michael Niedermayer2016-12-221-4/+6
| | | | | | | | | | Tested-by: Thomas Turner <thomastdt@googlemail.com> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
* | avutil/random_seed: Use uint64 instead of uint8 for struct to avoid ↵Michael Niedermayer2016-12-211-1/+1
| | | | | | | | | | | | potential alignment issues Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
* | Merge commit 'd12b5b2f135aade4099f4b26b0fe678656158c13'Derek Buitenhuis2016-05-111-26/+0
|\| | | | | | | | | | | | | | | * commit 'd12b5b2f135aade4099f4b26b0fe678656158c13': build: Split test programs off into separate files Some conversions done by: James Almer <jamrial@gmail.com> Merged-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
* | avutil/random_seed: Add the runtime in cycles of the main loop to the ↵Michael Niedermayer2016-03-101-1/+6
| | | | | | | | | | | | | | | | entropy pool This should theoretically improve the randomness slightly Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
* | lavu/random_seed: use arc4random() when availableGanesh Ajjanagadde2015-12-171-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | arc4random() was designed as a superior interface for system random number generation, designed for OpenBSD and subsequently incorporated by other BSD's, Mac OS X, and some non-standard libc's. It is thus an improvement to use it whenever available. As a side note, this may or may not get included in glibc, and there is a proposal to create a posix_random family based on these ideas: http://austingroupbugs.net/view.php?id=859. Tested on Mac OS X. Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
* | msvc: fix implicitly declared read/close.Matthew Oliver2014-08-021-0/+3
| | | | | | | | Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
* | Merge commit '01d245ef4392152dbdc78a6ba4dfa0a6e8b08e6f'Michael Niedermayer2014-01-061-9/+9
|\| | | | | | | | | | | | | | | | | | | | | * commit '01d245ef4392152dbdc78a6ba4dfa0a6e8b08e6f': random_seed: Rewrite the generic clock() based seed code Conflicts: libavutil/random_seed.c See: 66531c75d3bfd8a013acd8bd3c04a131dae2a1a0 Merged-by: Michael Niedermayer <michaelni@gmx.at>
| * random_seed: Rewrite the generic clock() based seed codeMichael Niedermayer2014-01-061-21/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The new code is faster and reuses the previous state in case of multiple calls. The previous code could easily end up in near-infinite loops, if the difference between two clock() calls never was larger than 1. This makes fate-parseutils finish in finite time when run in wine, if CryptGenRandom isn't available (which e.g. isn't available if targeting Windows RT/metro). Patch originally by Michael Niedermayer but with some modifications by Martin Storsjö. Signed-off-by: Martin Storsjö <martin@martin.st>
* | Merge commit '880391ed2d2faf796ca3a16f63cec69767546a21'Michael Niedermayer2013-08-081-1/+2
|\| | | | | | | | | | | | | | | | | | | * commit '880391ed2d2faf796ca3a16f63cec69767546a21': libavutil: use avpriv_open() Conflicts: libavutil/random_seed.c Merged-by: Michael Niedermayer <michaelni@gmx.at>
| * libavutil: use avpriv_open()Rémi Denis-Courmont2013-08-071-1/+2
| | | | | | | | Signed-off-by: Anton Khirnov <anton@khirnov.net>
* | Merge commit '0a75d1da23b8659ec49391469bb592da12760077'Michael Niedermayer2012-10-121-0/+15
|\| | | | | | | | | | | | | | | | | | | | | | | | | * commit '0a75d1da23b8659ec49391469bb592da12760077': options_table: refs option is not snow-only random_seed: Support using CryptGenRandom on windows doc: update the faq entry about custom I/O Conflicts: doc/faq.texi libavcodec/options_table.h Merged-by: Michael Niedermayer <michaelni@gmx.at>
| * random_seed: Support using CryptGenRandom on windowsMartin Storsjö2012-10-111-0/+15
| | | | | | | | Signed-off-by: Martin Storsjö <martin@martin.st>
| * random_seed: Only read /dev/*random if we have unistd.hRonald S. Bultje2012-06-291-0/+8
| | | | | | | | | | | | | | | | unistd.h is used for open/read/close, but if this header does not exist, there's probably no use in trying to open /dev/*random at all. Signed-off-by: Martin Storsjö <martin@martin.st>
* | random_seed: fix digest sizeMichael Niedermayer2012-10-111-1/+1
| | | | | | | | Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
* | random_seed: fix out of array readMichael Niedermayer2012-10-111-1/+1
| | | | | | | | | | Fixes CID733787 Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
* | random_seed: Replace a VLA with a normal arrayDerek Buitenhuis2012-09-081-1/+4
| | | | | | | | | | Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com> Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
* | random_seed: Only read /dev/*random if we have unistd.hRonald S. Bultje2012-09-071-0/+8
| | | | | | | | | | | | | | | | | | unistd.h is used for open/read/close, but if this header does not exist, there's probably no use in trying to open /dev/*random at all. Signed-off-by: Martin Storsjö <martin@martin.st> Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
* | random_seed: rewrite generic code.Michael Niedermayer2012-06-111-21/+38
| | | | | | | | | | | | | | | | | | The new code is faster and reuses the previous state in case of multiple calls. For testing the iterations are reduced and several entropy sources are disabled. Its based on SHA-1 Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
* | random_seed: add selftestMichael Niedermayer2012-02-231-0/+26
| | | | | | | | | | Reviewed-by: Nicolas George <nicolas.george@normalesup.org> Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
* | Merge remote-tracking branch 'qatar/master'Michael Niedermayer2011-12-051-14/+14
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * qatar/master: adpcmenc: cosmetics: pretty-printing ac3dec: cosmetics: pretty-printing yuv4mpeg: cosmetics: pretty-printing shorten: remove dead initialization roqvideodec: set AVFrame reference before reget_buffer. bmp: fix some 1bit samples. latmdec: add fate test for audio config change oma: PCM support oma: better format detection with small probe buffer oma: clearify ambiguous if condition wavpack: Properly clip samples during lossy decode Code clean-up for crc.c, lfg.c, log.c, random_see.d, rational.c and tree.c. Cleaned pixdesc.c file in libavutil zmbv.c: coding style clean-up. xan.c: coding style clean-up. mpegvideo.c: code cleanup - first 500 lines. Conflicts: Changelog libavcodec/adpcmenc.c libavcodec/bmp.c libavcodec/zmbv.c libavutil/log.c libavutil/pixdesc.c Merged-by: Michael Niedermayer <michaelni@gmx.at>
| * Code clean-up for crc.c, lfg.c, log.c, random_see.d, rational.c and tree.c.Yordan Makariev2011-12-031-14/+14
| | | | | | | | Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
* | Merge remote-tracking branch 'qatar/master'Michael Niedermayer2011-07-181-2/+2
|\| | | | | | | | | | | | | | | | | | | | | | | * qatar/master: vf_libopencv: replace opencv/cxtypes.h #include by opencv/cxcore.h dsputil: remove disabled code tta: remove disabled code gxfenc: place variable declarations before statements x86: Use LOCAL_ALIGNED in mpegvideo_mmx_template random_seed: use proper #includes Merged-by: Michael Niedermayer <michaelni@gmx.at>
| * random_seed: use proper #includesMans Rullgard2011-07-171-2/+2
| | | | | | | | | | | | Use <> for system headers, add needed math.h, drop unnecessary avutil.h. Signed-off-by: Mans Rullgard <mans@mansr.com>
* | Merge remote branch 'qatar/master'Michael Niedermayer2011-04-211-8/+0
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * qatar/master: Makefile: Include dependencies for test tools, too Remove a version check in av_log made unnecessary by the big bump. update last major version increase dates in APIchanges Reduce picture size for yadif. oggdec: use av_freep() instead of av_free() avio: Fix sanity checks in ffurl_read* libavformat: Free AVFormatContext->streams libavformat: Make protocols pass URLContext as log context where available asf: remove commented out code in asf_read_seek not pulled: libpostproc: Remove crufty code disabled by the big bump. Reflect 0.7_beta1 release in the Changelog not pulled: sws: remove disabled cruft. lavu: remove disabled ff_random_get_seed cruft. lavu: remove disabled sha1 cruft. Conflicts: Changelog libavutil/sha1.h Merged-by: Michael Niedermayer <michaelni@gmx.at>
| * lavu: remove disabled ff_random_get_seed cruft.Anton Khirnov2011-04-191-8/+0
| |
| * Replace FFmpeg with Libav in licence headersMans Rullgard2011-03-191-4/+4
|/ | | | Signed-off-by: Mans Rullgard <mans@mansr.com>
* Fix infinite loop with clock() returning (clock_t)-1.Michael Niedermayer2010-07-081-6/+6
| | | | Originally committed as revision 24116 to svn://svn.ffmpeg.org/ffmpeg/trunk
* Change i to unsigned in get_generic_seed().Michael Niedermayer2010-07-081-2/+2
| | | | | | | This is clearer than comparing against an unsigned number to force an unsigned comparison that we need. Originally committed as revision 24114 to svn://svn.ffmpeg.org/ffmpeg/trunk
* get_generic_seed() for the cases without /dev/random and AV_READ_TIMEMichael Niedermayer2010-07-071-6/+34
| | | | Originally committed as revision 24102 to svn://svn.ffmpeg.org/ffmpeg/trunk
* random_seed: simplifyMåns Rullgård2010-07-011-5/+3
| | | | Originally committed as revision 23932 to svn://svn.ffmpeg.org/ffmpeg/trunk
* ReindentMåns Rullgård2010-07-011-1/+1
| | | | Originally committed as revision 23931 to svn://svn.ffmpeg.org/ffmpeg/trunk
* random_seed: allow to block on /dev/randomMåns Rullgård2010-07-011-3/+0
| | | | | | | | | | If both /dev/random and /dev/urandom failed to return data, an uninitialised value might be returned. Since most systems have a non-blocking /dev/urandom or have /dev/random with similar properties, the chance of blocking is minimal, and the alternative of returning non-random data is worse. Originally committed as revision 23930 to svn://svn.ffmpeg.org/ffmpeg/trunk
* Make av_get_random_seed() non-blockingMåns Rullgård2010-06-301-10/+24
| | | | | | | Attempt to read from /dev/urandom and /dev/random with O_NONBLOCK set. If neither succeeds, proceed with fallbacks. Originally committed as revision 23903 to svn://svn.ffmpeg.org/ffmpeg/trunk
* Make ff_random_get_seed public, rename to av_get_random_seed, export the headerMartin Storsjö2010-05-231-1/+10
| | | | | | | Keep an old ff_ named function for binary compatibility until the next major bump. Originally committed as revision 23254 to svn://svn.ffmpeg.org/ffmpeg/trunk
* indentMåns Rullgård2010-03-111-1/+1
| | | | Originally committed as revision 22451 to svn://svn.ffmpeg.org/ffmpeg/trunk
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