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* global: mark code units that generate warnings with `-Wsign-compare`Patrick Steinhardt2024-12-061-0/+2
| | | | | | | | | Mark code units that generate warnings with `-Wsign-compare`. This allows for a structured approach to get rid of all such warnings over time in a way that can be easily measured. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* trace2: emit 'def_param' set with 'cmd_name' eventJeff Hostetler2024-03-071-0/+3
| | | | | | | | | | | | | | | | | Some commands do not cause a set of 'def_param' events to be emitted. This includes "git-remote-https", "git-http-fetch", and various "query" commands, like "git --man-path". Since all of these commands do emit a 'cmd_name' event, add code to the "trace2_cmd_name()" function to generate the set of 'def_param' events. Remove explicit calls to "trace2_cmd_list_config()" and "trace2_cmd_list_env_vars()" in git.c since they are no longer needed. Reviewed-by: Josh Steadmon <steadmon@google.com> Signed-off-by: Jeff Hostetler <jeffhostetler@github.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* trace2: avoid emitting 'def_param' set more than onceJeff Hostetler2024-03-071-0/+12
| | | | | | | | | | | | | During nested alias expansion it is possible for "trace2_cmd_list_config()" and "trace2_cmd_list_env_vars()" to be called more than once. This causes a full set of 'def_param' events to be emitted each time. Let's avoid that. Add code to those two functions to only emit them once. Signed-off-by: Jeff Hostetler <jeffhostetler@github.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Merge branch 'en/header-cleanup'Junio C Hamano2024-01-081-3/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove unused header "#include". * en/header-cleanup: treewide: remove unnecessary includes in source files treewide: add direct includes currently only pulled in transitively trace2/tr2_tls.h: remove unnecessary include submodule-config.h: remove unnecessary include pkt-line.h: remove unnecessary include line-log.h: remove unnecessary include http.h: remove unnecessary include fsmonitor--daemon.h: remove unnecessary includes blame.h: remove unnecessary includes archive.h: remove unnecessary include treewide: remove unnecessary includes in source files treewide: remove unnecessary includes from header files
| * treewide: remove unnecessary includes in source filesElijah Newren2023-12-261-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Each of these were checked with gcc -E -I. ${SOURCE_FILE} | grep ${HEADER_FILE} to ensure that removing the direct inclusion of the header actually resulted in that header no longer being included at all (i.e. that no other header pulled it in transitively). ...except for a few cases where we verified that although the header was brought in transitively, nothing from it was directly used in that source file. These cases were: * builtin/credential-cache.c * builtin/pull.c * builtin/send-pack.c Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | trace2: redact passwords from https:// URLs by defaultJohannes Schindelin2023-11-231-3/+117
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is an unsafe practice to call something like git clone https://user:password@example.com/ This not only risks leaking the password "over the shoulder" or into the readline history of the current Unix shell, it also gets logged via Trace2 if enabled. Let's at least avoid logging such secrets via Trace2, much like we avoid logging secrets in `http.c`. Much like the code in `http.c` is guarded via `GIT_TRACE_REDACT` (defaulting to `true`), we guard the new code via `GIT_TRACE2_REDACT` (also defaulting to `true`). The new tests added in this commit uncover leaks in `builtin/clone.c` and `remote.c`. Therefore we need to turn off `TEST_PASSES_SANITIZE_LEAK`. The reasons: - We observed that `the_repository->remote_status` is not released properly. - We are using `url...insteadOf` and that runs into a code path where an allocated URL is replaced with another URL, and the original URL is never released. - `remote_states` contains plenty of `struct remote`s whose refspecs seem to be usually allocated by never released. More investigation is needed here to identify the exact cause and proper fixes for these leaks/bugs. Co-authored-by: Jeff Hostetler <jeffhostetler@github.com> Signed-off-by: Jeff Hostetler <jeffhostetler@github.com> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* wrapper: use trace2 counters to collect fsync statsBeat Bolli2023-07-201-1/+0
| | | | | | | | | | | | | | | | | As mentioned in the thread starting at [1], trace2 counters should be used to count events instead of ad-hoc static variables. Convert the two fsync static variables to trace2 counters, reducing the coupling between wrapper.c and the trace2 subsystem. Adjust t/t5351 to match the trace2 counter output format. The counters are not per-thread because the ones being replaced also were not. [1] https://lore.kernel.org/git/20230627195251.1973421-2-calvinwan@google.com/ Signed-off-by: Beat Bolli <dev+git@drbeat.li> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* trace2: plumb config kviGlen Choo2023-06-281-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | There is a code path starting from trace2_def_param_fl() that eventually calls current_config_scope(), and thus it needs to have "kvi" plumbed through it. Additional plumbing is also needed to get "kvi" to trace2_def_param_fl(), which gets called by two code paths: - Through tr2_cfg_cb(), which is a config callback, so it trivially receives "kvi" via the "struct config_context ctx" parameter. - Through tr2_list_env_vars_fl(), which is a high level function that lists environment variables for tracing. This has been secretly behaving like git_config_from_parameters() (in that it parses config from environment variables/the CLI), but does not set config source information. Teach tr2_list_env_vars_fl() to be well-behaved by using kvi_from_param(), which is used elsewhere for CLI/environment variable-based config. As a result, current_config_scope() has no more callers, so remove it. Signed-off-by: Glen Choo <chooglen@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* hash-ll.h: split out of hash.h to remove dependency on repository.hElijah Newren2023-04-241-0/+1
| | | | | | | | | | | | | | | | | | | hash.h depends upon and includes repository.h, due to the definition and use of the_hash_algo (defined as the_repository->hash_algo). However, most headers trying to include hash.h are only interested in the layout of the structs like object_id. Move the parts of hash.h that do not depend upon repository.h into a new file hash-ll.h (the "low level" parts of hash.h), and adjust other files to use this new header where the convenience inline functions aren't needed. This allows hash.h and object.h to be fairly small, minimal headers. It also exposes a lot of hidden dependencies on both path.h (which was brought in by repository.h) and repository.h (which was previously implicitly brought in by object.h), so also adjust other files to be more explicit about what they depend upon. Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* treewide: be explicit about dependence on trace.h & trace2.hElijah Newren2023-04-111-0/+1
| | | | | | | | | | | Dozens of files made use of trace and trace2 functions, without explicitly including trace.h or trace2.h. This made it more difficult to find which files could remove a dependence on cache.h. Make C files explicitly include trace.h or trace2.h if they are using them. Signed-off-by: Elijah Newren <newren@gmail.com> Acked-by: Calvin Wan <calvinwan@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* treewide: remove unnecessary cache.h includes in source filesElijah Newren2023-02-241-1/+2
| | | | | | | | | | | | | We had several C files include cache.h unnecessarily. Replace those with an include of "git-compat-util.h" instead. Much like the previous commit, these have all been verified via both ensuring that gcc -E $SOURCE_FILE | grep '"cache.h"' found no hits and that make DEVELOPER=1 ${OBJECT_FILE_FOR_SOURCE_FILE} successfully compiles without warnings. Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* trace2: add global counter mechanismJeff Hostetler2022-10-241-7/+45
| | | | | | | | | | | | | | | | | | | | | | | | Add global counters mechanism to Trace2. The Trace2 counters mechanism adds the ability to create a set of global counter variables and an API to increment them efficiently. Counters can optionally report per-thread usage in addition to the sum across all threads. Counter events are emitted to the Trace2 logs when a thread exits and at process exit. Counters are an alternative to `data` and `data_json` events. Counters are useful when you want to measure something across the life of the process, when you don't want per-measurement events for performance reasons, when the data does not fit conveniently within a region, or when your control flow does not easily let you write the final total. For example, you might use this to report the number of calls to unzip() or the number of de-delta steps during a checkout. Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* trace2: add stopwatch timersJeff Hostetler2022-10-241-0/+75
| | | | | | | | | | | | | | | | | | | | | | Add stopwatch timer mechanism to Trace2. Timers are an alternative to Trace2 Regions. Regions are useful for measuring the time spent in various computation phases, such as the time to read the index, time to scan for unstaged files, time to scan for untracked files, and etc. However, regions are not appropriate in all places. For example, during a checkout, it would be very inefficient to use regions to measure the total time spent inflating objects from the ODB from across the entire lifetime of the process; a per-unzip() region would flood the output and significantly slow the command; and some form of post-processing would be requried to compute the time spent in unzip(). Timers can be used to measure a series of timer intervals and emit a single summary event (at thread and/or process exit). Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* trace2: rename the thread_name argument to trace2_thread_startJeff Hostetler2022-10-241-3/+3
| | | | | | | | | | | | | | | | Rename the `thread_name` argument in `tr2tls_create_self()` and `trace2_thread_start()` to be `thread_base_name` to make it clearer that the passed argument is a component used in the construction of the actual `struct tr2tls_thread_ctx.thread_name` variable. The base name will be used along with the thread id to create a unique thread name. This commit does not change how the `thread_name` field is allocated or stored within the `tr2tls_thread_ctx` structure. Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* tr2tls: clarify TLS terminologyJeff Hostetler2022-10-241-1/+1
| | | | | | | | | | | | | | | Reduce or eliminate use of the term "TLS" in the Trace2 code. The term "TLS" has two popular meanings: "thread-local storage" and "transport layer security". In the Trace2 source, the term is associated with the former. There was concern on the mailing list about it refering to the latter. Update the source and documentation to eliminate the use of the "TLS" term or replace it with the phrase "thread-local storage" to reduce ambiguity. Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* common-main.c: move non-trace2 exit() behavior out of trace2.cÆvar Arnfjörð Bjarmason2022-06-021-6/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change the exit() wrapper added in ee4512ed481 (trace2: create new combined trace facility, 2019-02-22) so that we'll split up the trace2 logging concerns from wanting to wrap the "exit()" function itself for other purposes. This makes more sense structurally, as we won't seem to conflate non-trace2 behavior with the trace2 code. I'd previously added an explanation for this in 368b5843158 (common-main.c: call exit(), don't return, 2021-12-07), that comment is being adjusted here. Now the only thing we'll do if we're not using trace2 is to truncate the "code" argument to the lowest 8 bits. We only need to do that truncation on non-POSIX systems, but in ee4512ed481 that "if defined(__MINGW32__)" code added in 47e3de0e796 (MinGW: truncate exit()'s argument to lowest 8 bits, 2009-07-05) was made to run everywhere. It might be good for clarify to narrow that down by an "ifdef" again, but I'm not certain that in the interim we haven't had some other non-POSIX systems rely the behavior. On a POSIX system taking the lowest 8 bits is implicit, see exit(3)[1] and wait(2)[2]. Let's leave a comment about that instead. 1. https://man7.org/linux/man-pages/man3/exit.3.html 2. https://man7.org/linux/man-pages/man2/wait.2.html Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* trace2: add stats for fsync operationsNeeraj Singh2022-03-301-0/+1
| | | | | | | | | | | | Add some global trace2 statistics for the number of fsyncs performed during the lifetime of a Git process. These stats are printed as part of trace2_cmd_exit_fl, which is presumably where we might want to print any other cross-cutting statistics. Signed-off-by: Neeraj Singh <neerajsi@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* C99: remove hardcoded-out !HAVE_VARIADIC_MACROS codeÆvar Arnfjörð Bjarmason2022-02-221-39/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove the "else" branches of the HAVE_VARIADIC_MACROS macro, which have been unconditionally omitted since 765dc168882 (git-compat-util: always enable variadic macros, 2021-01-28). Since were always omitted, anyone trying to use a compiler without variadic macro support to compile a git since version git v2.31.0 or later would have had a compilation error. 10 months across a few releases since then should have been enough time for anyone who cared to run into that and report the issue. In addition to that, for anyone unsetting HAVE_VARIADIC_MACROS we've been emitting extremely verbose warnings since at least ee4512ed481 (trace2: create new combined trace facility, 2019-02-22). That's because there is no such thing as a "region_enter_printf" or "region_leave_printf" format, so at least under GCC and Clang everything that includes trace.h (almost every file) emits a couple of warnings about that. There's a large benefit to being able to have a hard dependency rely on variadic macros, the code surrounding usage.c is hard to maintain if we need to write two implementations of everything, and by relying on "__FILE__" and "__LINE__" along with "__VA_ARGS__" we can in the future make error(), die() etc. log where they were called from. We've also recently merged d67fc4bf0ba (Merge branch 'bc/require-c99', 2021-12-10) which further cements our hard dependency on C99. So let's delete the fallback code, and update our CodingGuidelines to note that we depend on this. The added bullet-point starts with lower-case for consistency with other bullet-points in that section. The diff in "trace.h" is relatively hard to read, since we need to retain the existing API docs, which were comments on the code used if HAVE_VARIADIC_MACROS was not defined. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* trace2: add trace2_child_ready() to report on background childrenJeff Hostetler2021-09-201-0/+31
| | | | | | | | | | | | | | | | | | | | | | Create "child_ready" event to capture the state of a child process created in the background. When a child command is started a "child_start" event is generated in the Trace2 log. For normal synchronous children, a "child_exit" event is later generated when the child exits or is terminated. The two events include information, such as the "child_id" and "pid", to allow post analysis to match-up the command line and exit status. When a child is started in the background (and may outlive the parent process), it is not possible for the parent to emit a "child_exit" event. Create a new "child_ready" event to indicate whether the child was successfully started. Also include the "child_id" and "pid" to allow similar post processing. This will be used in a later commit with the new "start_bg_command()". Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* tr2: log parent process nameEmily Shaffer2021-07-221-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It can be useful to tell who invoked Git - was it invoked manually by a user via CLI or script? By an IDE? In some cases - like 'repo' tool - we can influence the source code and set the GIT_TRACE2_PARENT_SID environment variable from the caller process. In 'repo''s case, that parent SID is manipulated to include the string "repo", which means we can positively identify when Git was invoked by 'repo' tool. However, identifying parents that way requires both that we know which tools invoke Git and that we have the ability to modify the source code of those tools. It cannot scale to keep up with the various IDEs and wrappers which use Git, most of which we don't know about. Learning which tools and wrappers invoke Git, and how, would give us insight to decide where to improve Git's usability and performance. Unfortunately, there's no cross-platform reliable way to gather the name of the parent process. If procfs is present, we can use that; otherwise we will need to discover the name another way. However, the process ID should be sufficient to look up the process name on most platforms, so that code may be shareable. Git for Windows gathers similar information and logs it as a "data_json" event. However, since "data_json" has a variable format, it is difficult to parse effectively in some languages; instead, let's pursue a dedicated "cmd_ancestry" event to record information about the ancestry of the current process and a consistent, parseable way. Git for Windows also gathers information about more than one generation of parent. In Linux further ancestry info can be gathered with procfs, but it's unwieldy to do so. In the interest of later moving Git for Windows ancestry logging to the 'cmd_ancestry' event, and in the interest of later adding more ancestry to the Linux implementation - or of adding this functionality to other platforms which have an easier time walking the process tree - let's make 'cmd_ancestry' accept an array of parentage. Signed-off-by: Emily Shaffer <emilyshaffer@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* trace2: add a public function for getting the SIDJosh Steadmon2020-11-121-0/+5
| | | | | | | | Add a public wrapper, trace2_session_id(), around tr2_sid_get(), which is intended to be private trace2 implementation. Signed-off-by: Josh Steadmon <steadmon@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* trace2: teach Git to log environment variablesJosh Steadmon2020-03-231-0/+9
| | | | | | | | | | | | | | | Via trace2, Git can already log interesting config parameters (see the trace2_cmd_list_config() function). However, this can grant an incomplete picture because many config parameters also allow overrides via environment variables. To allow for more complete logs, we add a new trace2_cmd_list_env_vars() function and supporting implementation, modeled after the pre-existing config param logging implementation. Signed-off-by: Josh Steadmon <steadmon@google.com> Acked-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Merge branch 'jh/trace2'Junio C Hamano2019-05-131-1/+1
|\ | | | | | | | | | | | | | | A few embarrassing bugfixes. * jh/trace2: trace2: fix up a missing "leave" entry point trace2: fix incorrect function pointer check
| * trace2: fix incorrect function pointer checkJosh Steadmon2019-04-261-1/+1
| | | | | | | | | | | | | | | | Fix trace2_data_json_fl() to check for the presence of pfn_data_json_fl in its targets, rather than pfn_data_fl, which is not actually called. Signed-off-by: Josh Steadmon <steadmon@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | Merge branch 'jh/trace2-sid-fix'Junio C Hamano2019-05-131-2/+19
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Polishing of the new trace2 facility continues. The system-level configuration can specify site-wide trace2 settings, which can be overridden with per-user configuration and environment variables. * jh/trace2-sid-fix: trace2: fixup access problem on /etc/gitconfig in read_very_early_config trace2: update docs to describe system/global config settings trace2: make SIDs more unique trace2: clarify UTC datetime formatting trace2: report peak memory usage of the process trace2: use system/global config for default trace2 settings config: add read_very_early_config() trace2: find exec-dir before trace2 initialization trace2: add absolute elapsed time to start event trace2: refactor setting process starting time config: initialize opts structure in repo_read_config()
| * | trace2: report peak memory usage of the processJeff Hostetler2019-04-161-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | Teach Windows version of git to report peak memory usage during exit() processing. Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
| * | trace2: use system/global config for default trace2 settingsJeff Hostetler2019-04-161-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Teach git to read the system and global config files for default Trace2 settings. This allows system-wide Trace2 settings to be installed and inherited to make it easier to manage a collection of systems. The original GIT_TR2* environment variables are loaded afterwards and can be used to override the system settings. Only the system and global config files are used. Repo and worktree local config files are ignored. Likewise, the "-c" command line arguments are also ignored. These limits are for performance reasons. (1) For users not using Trace2, there should be minimal overhead to detect that Trace2 is not enabled. In particular, Trace2 should not allocate lots of otherwise unused data strucutres. (2) For accurate performance measurements, Trace2 should be initialized as early in the git process as possible, and before most of the normal git process initialization (which involves discovering the .git directory and reading a hierarchy of config files). Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
| * | trace2: add absolute elapsed time to start eventJeff Hostetler2019-04-161-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | Add elapsed process time to "start" event to measure the performance of early process startup. Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
| * | trace2: refactor setting process starting timeJeff Hostetler2019-04-161-1/+6
| |/ | | | | | | | | | | | | | | | | Create trace2_initialize_clock() and call from main() to capture process start time in isolation and before other sub-systems are ready. Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* / trace2: NULL is not allowed for va_listTorsten Bögershausen2019-03-201-4/+11
|/ | | | | | | | | | | | | | | | | | | | | | | | | Some compilers don't allow NULL to be passed for a va_list, and e.g. "gcc (Raspbian 6.3.0-18+rpi1+deb9u1) 6.3.0 20170516" errors out like this: trace2/tr2_tgt_event.c:193:18: error: invalid operands to binary && (have ‘int’ and ‘va_list {aka __va_list}’) if (fmt && *fmt && ap) { ^^ I couldn't find any hints that va_list and pointers can be mixed, and no hints that they can't either. Morten Welinder comments: "C99, Section 7.15, simply says that va_list "is an object type suitable for holding information needed by the macros va_start, va_end, and va_copy". So clearly not guaranteed to be mixable with pointers... The portable solution is to use "va_list" everywhere in the callchain. As a consequence, both trace2_region_enter_fl() and trace2_region_leave_fl() now take a variable argument list. Signed-off-by: Torsten Bögershausen <tboegi@web.de> Acked-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* trace2: create new combined trace facilityJeff Hostetler2019-02-231-0/+761
Create a new unified tracing facility for git. The eventual intent is to replace the current trace_printf* and trace_performance* routines with a unified set of git_trace2* routines. In addition to the usual printf-style API, trace2 provides higer-level event verbs with fixed-fields allowing structured data to be written. This makes post-processing and analysis easier for external tools. Trace2 defines 3 output targets. These are set using the environment variables "GIT_TR2", "GIT_TR2_PERF", and "GIT_TR2_EVENT". These may be set to "1" or to an absolute pathname (just like the current GIT_TRACE). * GIT_TR2 is intended to be a replacement for GIT_TRACE and logs command summary data. * GIT_TR2_PERF is intended as a replacement for GIT_TRACE_PERFORMANCE. It extends the output with columns for the command process, thread, repo, absolute and relative elapsed times. It reports events for child process start/stop, thread start/stop, and per-thread function nesting. * GIT_TR2_EVENT is a new structured format. It writes event data as a series of JSON records. Calls to trace2 functions log to any of the 3 output targets enabled without the need to call different trace_printf* or trace_performance* routines. Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>