Always use the internal "use_weak" random seed when initializing the "mimalloc" heap when statically linked on Windows. The imported "mimalloc" routines support several random sources to seed the heap data structures, including BCrypt.dll and RtlGenRandom. Crashes have been reported when using BCrypt.dll if it initialized during an `atexit()` handler function. Granted, such DLL initialization should not happen in an atexit handler, but yet the crashes remain. It should be noted that on Windows when statically linked, the mimalloc startup code (called by the GCC CRT to initialize static data prior to calling `main()`) always uses the internal "weak" random seed. "mimalloc" does not try to load an alternate random source until after the OS initialization has completed. Heap data is stored in `__declspec(thread)` TLS data and in theory each Git thread will have its own heap data. However, testing shows that the "mimalloc" library doesn't actually call `os_random_buf()` (to load a new random source) when creating these new per-thread heap structures. However, if an atexit handler is forced to run on a non-main thread, the "mimalloc" library *WILL* try to create a new heap and seed it with `os_random_buf()`. (The reason for this is still a mystery to this author.) The `os_random_buf()` call can cause the (previously uninitialized BCrypt.dll library) to be dynamically loaded and a call made into it. Crashes have been reported in v2.40.1.vfs.0.0 while in this call. As a workaround, the fix here forces the use of the internal "use_weak" random code for the subsequent `os_random_buf()` calls. Since we have been using that random generator for the majority of the program, it seems safe to use it for the final few mallocs in the atexit handler (of which there really shouldn't be that many. Signed-off-by: Jeff Hostetler <jeffhostetler@github.com> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Git - fast, scalable, distributed revision control system
Git is a fast, scalable, distributed revision control system with an unusually rich command set that provides both high-level operations and full access to internals.
Git is an Open Source project covered by the GNU General Public License version 2 (some parts of it are under different licenses, compatible with the GPLv2). It was originally written by Linus Torvalds with help of a group of hackers around the net.
Please read the file INSTALL for installation instructions.
Many Git online resources are accessible from https://git-scm.com/ including full documentation and Git related tools.
See Documentation/gittutorial.txt to get started, then see
Documentation/giteveryday.txt for a useful minimum set of commands, and
Documentation/git-<commandname>.txt for documentation of each command.
If git has been correctly installed, then the tutorial can also be
read with man gittutorial or git help tutorial, and the
documentation of each command with man git-<commandname> or git help <commandname>.
CVS users may also want to read Documentation/gitcvs-migration.txt
(man gitcvs-migration or git help cvs-migration if git is
installed).
The user discussion and development of Git take place on the Git mailing list -- everyone is welcome to post bug reports, feature requests, comments and patches to git@vger.kernel.org (read Documentation/SubmittingPatches for instructions on patch submission and Documentation/CodingGuidelines).
Those wishing to help with error message, usage and informational message
string translations (localization l10) should see po/README.md
(a po file is a Portable Object file that holds the translations).
To subscribe to the list, send an email to git+subscribe@vger.kernel.org (see https://subspace.kernel.org/subscribing.html for details). The mailing list archives are available at https://lore.kernel.org/git/, https://marc.info/?l=git and other archival sites.
Issues which are security relevant should be disclosed privately to the Git Security mailing list git-security@googlegroups.com.
The maintainer frequently sends the "What's cooking" reports that list the current status of various development topics to the mailing list. The discussion following them give a good reference for project status, development direction and remaining tasks.
The name "git" was given by Linus Torvalds when he wrote the very first version. He described the tool as "the stupid content tracker" and the name as (depending on your mood):
- random three-letter combination that is pronounceable, and not actually used by any common UNIX command. The fact that it is a mispronunciation of "get" may or may not be relevant.
- stupid. contemptible and despicable. simple. Take your pick from the dictionary of slang.
- "global information tracker": you're in a good mood, and it actually works for you. Angels sing, and a light suddenly fills the room.
- "goddamn idiotic truckload of sh*t": when it breaks