path: root/trace.c
AgeCommit message (Collapse)Author
2019-08-13packfile: drop release_pack_memory()Jeff King
Long ago, in 97bfeb34df (Release pack windows before reporting out of memory., 2006-12-24), we taught xmalloc() and friends to try unmapping pack windows when malloc() failed. It's unlikely that his helps a lot in practice, and it has some downsides. First, the downsides: 1. It makes xmalloc() not thread-safe. We've worked around this in pack-objects.c, which installs its own locking version of the try_to_free_routine(). But other threaded code doesn't. 2. It makes the system as a whole harder to reason about. Functions which allocate heap memory under the hood may have farther-reaching effects than expected. That might be worth the tradeoff if there's a benefit. But in practice, it seems unlikely. We're generally dealing with mmap'd files, so the OS is going to do a much better job at responding to memory pressure by dropping individual pages (the exception is systems with NO_MMAP, but even there the OS can probably respond just as well with swapping). So the only thing we're really freeing is address space. On 64-bit systems, we have plenty of that to go around. On 32-bit systems, it could possibly help. But around the same time we made two other changes: 77ccc5bbd1 (Introduce new config option for mmap limit., 2006-12-23) and 60bb8b1453 (Fully activate the sliding window pack access., 2006-12-23). Together that means that a 32-bit system should have no more than 256MB total of packed-git mmaps at one time, split between a few 32MB windows. It's unlikely we have any address space problems since then, but we don't have any data since the features were all added at the same time. Likewise, xmmap() will try to free memory. At first glance, it seems like we'd need this (when we try to mmap a new window, we might need to close an old one to save address space on a 32-bit system). But we're saved again by core.packedGitLimit: if we're going to exceed our 256MB limit, we'll close an existing window before we even call mmap(). So it seems unlikely that this feature is actually doing anything useful. And while we don't have reports of it harming anything (probably because it rarely if ever kicks in), it would be nice to simplify the system overall. This patch drops the whole try_to_free system from xmalloc(), as well as the manual pack memory release in xmmap(). Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2018-08-18trace.h: support nested performance tracingNguyễn Thái Ngọc Duy
Performance measurements are listed right now as a flat list, which is fine when we measure big blocks. But when we start adding more and more measurements, some of them could be just part of a bigger measurement and a flat list gives a wrong impression that they are executed at the same level instead of nested. Add trace_performance_enter() and trace_performance_leave() to allow indent these nested measurements. For now it does not help much because the only nested thing is (lazy) name hash initialization (e.g. called in diff-index from "git status"). This will help more because I'm going to add some more tracing that's actually nested. Signed-off-by: Nguyễn Thái Ngọc Duy <> Signed-off-by: Junio C Hamano <>
2018-03-30trace.c: export trace_setup_keyNguyễn Thái Ngọc Duy
This is so that we can print traces based on this key outside trace.c. Signed-off-by: Nguyễn Thái Ngọc Duy <> Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2018-01-16trace.c: move strbuf_release() out of print_trace_line()Nguyễn Thái Ngọc Duy
The function is about printing a trace line, not releasing the buffer it receives too. Move strbuf_release() back outside. This makes it easier to see how strbuf is managed. Signed-off-by: Nguyễn Thái Ngọc Duy <> Signed-off-by: Junio C Hamano <>
2018-01-16trace: avoid unnecessary quotingJeff King
Trace output which contains arbitrary strings (e.g., the arguments to commands which we are running) is always passed through sq_quote_buf(). That function always adds single-quotes, even if the output consists of vanilla characters. This can make the output a bit hard to read. Let's avoid the quoting if there are no characters which a shell would interpret. Trace output doesn't necessarily need to be shell-compatible, but: - the shell language is a good ballpark for what humans consider readable (well, humans versed in command line tools) - the run_command bits can be cut-and-pasted to a shell, and we'll keep that property - it covers any cases which would make the output visually ambiguous (e.g., embedded whitespace or quotes) Signed-off-by: Jeff King <> Signed-off-by: Nguyễn Thái Ngọc Duy <> Signed-off-by: Junio C Hamano <>
2018-01-16sq_quote_argv: drop maxlen parameterJeff King
No caller passes anything but "0" for this parameter, which requests that the function ignore it completely. In fact, in all of history there was only one such caller, and it went away in 7f51f8bc2b (alias: use run_command api to execute aliases, 2011-01-07). Signed-off-by: Jeff King <> Signed-off-by: Nguyễn Thái Ngọc Duy <> Signed-off-by: Junio C Hamano <>
2017-12-06trace: improve performance while category is disabledGennady Kupava
Move just enough code from trace.c into trace.h header so all code necessary to determine that trace is disabled could be inlined to calling functions. Then perform the check if the trace key is enabled sooner in call chain. Signed-off-by: Gennady Kupava <> Signed-off-by: Junio C Hamano <>
2017-11-27trace: remove trace key normalizationGennady Kupava
Trace key normalization is not used, not strictly necessary, complicates the code and would negatively affect compilation speed if moved to header. New trace_default_key key or existing separate marco could be used instead of passing NULL as a key. Signed-off-by: Gennady Kupava <> Signed-off-by: Junio C Hamano <>
2017-11-09Replace Free Software Foundation address in license noticesTodd Zullinger
The mailing address for the FSF has changed over the years. Rather than updating the address across all files, refer readers to, as the GNU GPL documentation now suggests for license notices. The mailing address is retained in the full license files (COPYING and LGPL-2.1). The old address is still present in t/diff-lib/COPYING. This is intentional, as the file is used in tests and the contents are not expected to change. Signed-off-by: Todd Zullinger <> Signed-off-by: Junio C Hamano <>
2016-08-05trace: do not fall back to stderrJeff King
If the trace code cannot open a specified file, or does not understand the contents of the GIT_TRACE variable, it falls back to printing trace output to stderr. This is an attempt to be helpful, but in practice it just ends up annoying. The user was trying to get the output to go somewhere else, so spewing it to stderr does not really accomplish that. And as it's intended for debugging, they can presumably re-run the command with their error corrected. So instead of falling back, this patch disables bogus trace keys for the rest of the program, just as we do for write errors. We can drop the "Defaulting to..." part of the error message entirely; after seeing "cannot open '/foo'", the user can assume that tracing is skipped. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2016-08-05trace: disable key after write errorJeff King
If we get a write error writing to a trace descriptor, the error isn't likely to go away if we keep writing. Instead, you'll just get the same error over and over. E.g., try: GIT_TRACE_PACKET=42 git ls-remote >/dev/null You don't really need to see: warning: unable to write trace for GIT_TRACE_PACKET: Bad file descriptor hundreds of times. We could fallback to tracing to stderr, as we do in the error code-path for open(), but there's not much point. If the user fed us a bogus descriptor, they're probably better off fixing their invocation. And if they didn't, and we saw a transient error (e.g., ENOSPC writing to a file), it probably doesn't help anybody to have half of the trace in a file, and half on stderr. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2016-08-05trace: correct variable name in write() error messageJeff King
Our error message for write() always mentions GIT_TRACE, even though we may be writing for a different variable entirely. It's also not quite accurate to say "fd given by GIT_TRACE environment variable", as we may hit this error based on a filename the user put in the variable (we do complain and switch to stderr if the file cannot be opened, but it's still possible to hit a write() error on the descriptor later). So let's fix those things, and switch to our more usual "unable to do X: Y" format for the error. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2016-08-05trace: cosmetic fixes for error messagesJeff King
The error messages for the trace code are often multi-line; the first line gets a nice "warning:", but the rest are left-aligned. Let's give them an indentation to make sure they stand out as a unit. While we're here, let's also downcase the first letter of each error (our usual style), and break up a long line of advice (since we're already using multiple lines, one more doesn't hurt). We also replace "What does 'foo' for GIT_TRACE mean?". While cute, it's probably a good idea to give more context, and follow our usual styles. So it's now "unknown trace value for 'GIT_TRACE': foo". Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2016-08-05trace: use warning() for printing trace errorsJeff King
Right now we just fprintf() straight to stderr, which can make the output hard to distinguish. It would be helpful to give it one of our usual prefixes like "error:", "warning:", etc. It doesn't make sense to use error() here, as the trace code is "optional" debugging code. If something goes wrong, we should warn the user, but saying "error" implies the actual git operation had a problem. So warning() is the only sane choice. Note that this does end up calling warn_routine() to do the formatting. This is probably a good thing, since they are clearly trying to hook messages before they make it to stderr. However, it also means that in theory somebody who tries to trace from their warn_routine() could cause a loop. This seems rather unlikely in practice (we've never even overridden the default warn_builtin routine before, and recent discussions to do so would just install a noop routine). Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2016-08-04trace: stop using write_or_whine_pipe()Jeff King
The write_or_whine_pipe function does two things: 1. it checks for EPIPE and converts it into a signal death 2. it prints a message to stderr on error The first thing does not help us, and actively hurts. Generally we would simply die from SIGPIPE in this case, unless somebody has taken the time to ignore SIGPIPE for the whole process. And if they _did_ do that, it seems rather silly for the trace code, which otherwise takes pains to continue even in the face of errors (e.g., by not using write_or_die!), to take down the whole process for one specific type of error. Nor does the second thing help us; it just makes it harder to write our error message, because we have to feed bits of it as an argument to write_or_whine_pipe(). Translators never get to see the full message, and it's hard for us to customize it. Let's switch to just using write_in_full() and writing our own error string. For now, the error is identical to what write_or_whine_pipe() would say, but now that it's more under our control, we can improve it in future patches. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2016-08-04trace: handle NULL argument in trace_disable()Jeff King
All of the trace functions treat a NULL key as a synonym for the default GIT_TRACE key. Except for trace_disable(), which will segfault. Fortunately, this can't cause any bugs, as the function has no callers. But rather than drop it, let's fix the bug, as I plan to add a caller. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2015-09-25trace: use strbuf for quote_crnl outputJeff King
When we output GIT_TRACE_SETUP paths, we quote any meta-characters. But our buffer to hold the result is only PATH_MAX bytes, and we could double the size of the input path (if every character needs quoting). We could use a 2*PATH_MAX buffer, if we assume the input will never be more than PATH_MAX. But it's easier still to just switch to a strbuf and not worry about whether the input can exceed PATH_MAX or not. The original copied the "p2" pointer to "p1", advancing both. Since this gets rid of "p1", let's also drop "p2", whose name is now confusing. We can just advance the original "path" pointer. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2015-06-16pkt-line: support tracing verbatim pack contentsJeff King
When debugging the pack protocol, it is sometimes useful to store the verbatim pack that we sent or received on the wire. Looking at the on-disk result is often not helpful for a few reasons: 1. If the operation is a clone, we destroy the repo on failure, leaving nothing on disk. 2. If the pack is small, we unpack it immediately, and the full pack never hits the disk. 3. If we feed the pack to "index-pack --fix-thin", the resulting pack has the extra delta bases added to it. We already have a GIT_TRACE_PACKET mechanism for tracing packets. Let's extend it with GIT_TRACE_PACKFILE to dump the verbatim packfile. There are a few other positive fallouts that come from rearranging this code: - We currently disable the packet trace after seeing the PACK header, even though we may get human-readable lines on other sidebands; now we include them in the trace. - We currently try to print "PACK ..." in the trace to indicate that the packfile has started. But because we disable packet tracing, we never printed this line. We will now do so. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2015-05-11Merge branch 'nd/multiple-work-trees'Junio C Hamano
A replacement for contrib/workdir/git-new-workdir that does not rely on symbolic links and make sharing of objects and refs safer by making the borrowee and borrowers aware of each other. * nd/multiple-work-trees: (41 commits) prune --worktrees: fix expire vs worktree existence condition t1501: fix test with split index t2026: fix broken &&-chain t2026 needs procondition SANITY git-checkout.txt: a note about multiple checkout support for submodules checkout: add --ignore-other-wortrees checkout: pass whole struct to parse_branchname_arg instead of individual flags git-common-dir: make "modules/" per-working-directory directory checkout: do not fail if target is an empty directory t2025: add a test to make sure grafts is working from a linked checkout checkout: don't require a work tree when checking out into a new one git_path(): keep "info/sparse-checkout" per work-tree count-objects: report unused files in $GIT_DIR/worktrees/... gc: support prune --worktrees gc: factor out gc.pruneexpire parsing code gc: style change -- no SP before closing parenthesis checkout: clean up half-prepared directories in --to mode checkout: reject if the branch is already checked out elsewhere prune: strategies for linked checkouts checkout: support checking out into a new working directory ... check for clock_gettime and CLOCK_MONOTONICReuben Hawkins
Set or clear Makefile variables HAVE_CLOCK_GETTIME and HAVE_CLOCK_MONOTONIC based upon results of the checks (overriding default values from config.mak.uname). CLOCK_MONOTONIC isn't available on RHEL3, but there are still RHEL3 systems being used in production. Signed-off-by: Reuben Hawkins <> Reviewed-by: Eric Sunshine <> Signed-off-by: Junio C Hamano <>
2014-12-22Merge branch 'rs/use-strbuf-complete-line'Junio C Hamano
* rs/use-strbuf-complete-line: use strbuf_complete_line() for adding a newline if needed
2014-12-12use strbuf_complete_line() for adding a newline if neededRené Scharfe
Call strbuf_complete_line() instead of open-coding it. Also remove surrounding comments indicating the intent to complete a line since this information is already included in the function name. Signed-off-by: Rene Scharfe <> Signed-off-by: Junio C Hamano <>
2014-12-01setup.c: support multi-checkout repo setupNguyễn Thái Ngọc Duy
The repo setup procedure is updated to detect $GIT_DIR/commondir and set $GIT_COMMON_DIR properly. The core.worktree is ignored when $GIT_COMMON_DIR is set. This is because the config file is shared in multi-checkout setup, but checkout directories _are_ different. Making core.worktree effective in all checkouts mean it's back to a single checkout. Helped-by: Johannes Sixt <> Signed-off-by: Nguyễn Thái Ngọc Duy <> Signed-off-by: Junio C Hamano <>
2014-10-16Merge branch 'bw/trace-no-inline-getnanotime'Junio C Hamano
No file-scope static variables in an inlined function, please. * bw/trace-no-inline-getnanotime: trace.c: do not mark getnanotime() as "inline"
2014-09-29trace.c: do not mark getnanotime() as "inline"Ben Walton
Oracle Studio compilers don't allow for static variables in functions that are defined to be inline. GNU C does permit this. Let's reference the C99 standard though, which doesn't allow for inline functions to contain modifiable static variables. Signed-off-by: Ben Walton <> Signed-off-by: Junio C Hamano <>
2014-09-19Merge branch 'kb/perf-trace'Junio C Hamano
Compilation fix for some compilers. * kb/perf-trace: trace: correct trace_strbuf() parameter type for !HAVE_VARIADIC_MACROS
2014-09-08trace: correct trace_strbuf() parameter type for !HAVE_VARIADIC_MACROSRené Scharfe
Reported-by: dev <> Signed-off-by: Rene Scharfe <> Signed-off-by: Junio C Hamano <>
2014-09-02Merge branch 'rs/strbuf-getcwd'Junio C Hamano
Reduce the use of fixed sized buffer passed to getcwd() calls by introducing xgetcwd() helper. * rs/strbuf-getcwd: use strbuf_add_absolute_path() to add absolute paths abspath: convert absolute_path() to strbuf use xgetcwd() to set $GIT_DIR use xgetcwd() to get the current directory or die wrapper: add xgetcwd() abspath: convert real_path_internal() to strbuf abspath: use strbuf_getcwd() to remember original working directory setup: convert setup_git_directory_gently_1 et al. to strbuf unix-sockets: use strbuf_getcwd() strbuf: add strbuf_getcwd()
2014-08-26use xgetcwd() to get the current directory or dieRené Scharfe
Convert several calls of getcwd() and die() to use xgetcwd() instead. This way we get rid of fixed-size buffers (which can be too small depending on the used file system) and gain consistent error messages. Signed-off-by: Rene Scharfe <> Signed-off-by: Junio C Hamano <>
2014-07-14git: add performance tracing for git's main() function to debug scriptsKarsten Blees
Use trace_performance to measure and print execution time and command line arguments of the entire main() function. In constrast to the shell's 'time' utility, which measures total time of the parent process, this logs all involved git commands recursively. This is particularly useful to debug performance issues of scripted commands (i.e. which git commands were called with which parameters, and how long did they execute). Due to git's deliberate use of exit(), the implementation uses an atexit routine rather than just adding trace_performance_since() at the end of main(). Usage example: > GIT_TRACE_PERFORMANCE=~/git-trace.log git stash list Creates a log file like this: 23:57:38.638765 trace.c:405 performance: 0.000310107 s: git command: 'git' 'rev-parse' '--git-dir' 23:57:38.644387 trace.c:405 performance: 0.000261759 s: git command: 'git' 'rev-parse' '--show-toplevel' 23:57:38.646207 trace.c:405 performance: 0.000304468 s: git command: 'git' 'config' '--get-colorbool' 'color.interactive' 23:57:38.648491 trace.c:405 performance: 0.000241667 s: git command: 'git' 'config' '--get-color' '' 'red bold' 23:57:38.650465 trace.c:405 performance: 0.000243063 s: git command: 'git' 'config' '--get-color' '' 'reset' 23:57:38.654850 trace.c:405 performance: 0.025126313 s: git command: 'git' 'stash' 'list' Signed-off-by: Karsten Blees <> Signed-off-by: Junio C Hamano <>
2014-07-14trace: add trace_performance facility to debug performance issuesKarsten Blees
Add trace_performance and trace_performance_since macros that print a duration and an optional printf-formatted text to the file specified in environment variable GIT_TRACE_PERFORMANCE. These macros, in conjunction with getnanotime(), are intended to simplify performance measurements from within the application (i.e. profiling via manual instrumentation, rather than using an external profiling tool). Unless enabled via GIT_TRACE_PERFORMANCE, these macros have no noticeable impact on performance, so that test code for well known time killers may be shipped in release builds. Alternatively, a developer could provide an additional performance patch (not meant for master) that allows reviewers to reproduce performance tests more easily, e.g. on other platforms or using their own repositories. Usage examples: Simple use case (measure one code section): uint64_t start = getnanotime(); /* code section to measure */ trace_performance_since(start, "foobar"); Complex use case (measure repetitive code sections): uint64_t t = 0; for (;;) { /* ignore */ t -= getnanotime(); /* code section to measure */ t += getnanotime(); /* ignore */ } trace_performance(t, "frotz"); Signed-off-by: Karsten Blees <> Signed-off-by: Junio C Hamano <>
2014-07-14trace: add high resolution timer function to debug performance issuesKarsten Blees
Add a getnanotime() function that returns nanoseconds since 01/01/1970 as unsigned 64-bit integer (i.e. overflows in july 2554). This is easier to work with than e.g. struct timeval or struct timespec. Basing the timer on the epoch allows using the results with other time-related APIs. To simplify adaption to different platforms, split the implementation into a common getnanotime() and a platform-specific highres_nanos() function. The common getnanotime() function handles errors, falling back to gettimeofday() if highres_nanos() isn't implemented or doesn't work. getnanotime() is also responsible for normalizing to the epoch. The offset to the system clock is calculated only once on initialization, i.e. manually setting the system clock has no impact on the timer (except if the fallback gettimeofday() is in use). Git processes are typically short lived, so we don't need to handle clock drift. The highres_nanos() function returns monotonically increasing nanoseconds relative to some arbitrary point in time (e.g. system boot), or 0 on failure. Providing platform-specific implementations should be relatively easy, e.g. adapting to clock_gettime() as defined by the POSIX realtime extensions is seven lines of code. This version includes highres_nanos() implementations for: * Linux: using clock_gettime(CLOCK_MONOTONIC) * Windows: using QueryPerformanceCounter() Todo: * enable clock_gettime() on more platforms * add Mac OSX version, e.g. using mach_absolute_time + mach_timebase_info Signed-off-by: Karsten Blees <> Signed-off-by: Junio C Hamano <>
2014-07-14trace: add 'file:line' to all trace outputKarsten Blees
This is useful to see where trace output came from. Add 'const char *file, int line' parameters to the printing functions and rename them to *_fl. Add trace_printf* and trace_strbuf macros resolving to the *_fl functions and let the preprocessor fill in __FILE__ and __LINE__. As the trace_printf* functions take a variable number of arguments, this requires variadic macros (i.e. '#define foo(...) foo_impl(__VA_ARGS__)'. Though part of C99, it is unclear whether older compilers support this. Thus keep the old functions and only enable variadic macros for GNUC and MSVC 2005+ (_MSC_VER 1400). This has the nice side effect that the old C-style declarations serve as documentation how the macros are to be used. Print 'file:line ' as prefix to each trace line. Align the remaining trace output at column 40 to accommodate 18 char file names + 4 digit line number (currently there are 30 *.c files of length 18 and just 11 of 19). Trace output from longer source files (e.g. builtin/receive-pack.c) will not be aligned. Signed-off-by: Karsten Blees <> Signed-off-by: Junio C Hamano <>
2014-07-14trace: move code around, in preparation to file:line outputKarsten Blees
No functional changes, just move stuff around so that the next patch isn't that ugly... Signed-off-by: Karsten Blees <> Signed-off-by: Junio C Hamano <>
2014-07-14trace: add current timestamp to all trace outputKarsten Blees
This is useful to tell apart trace output of separate test runs. It can also be used for basic, coarse-grained performance analysis. Note that the accuracy is tainted by writing to the trace file, and you have to calculate the deltas yourself (which is next to impossible if multiple threads or processes are involved). Signed-off-by: Karsten Blees <> Signed-off-by: Junio C Hamano <>
2014-07-14trace: disable additional trace output for unit testsKarsten Blees
Some unit-tests use trace output to verify internal state, and unstable output such as timestamps and line numbers are not useful there. Disable additional trace output if GIT_TRACE_BARE is set. Signed-off-by: Karsten Blees <> Signed-off-by: Junio C Hamano <>
2014-07-14trace: add infrastructure to augment trace output with additional infoKarsten Blees
To be able to add a common prefix or suffix to all trace output (e.g. a timestamp or file:line of the caller), factor out common setup and cleanup tasks of the trace* functions. When adding a common prefix, it makes sense that the output of each trace call starts on a new line. Add '\n' in case the caller forgot. Note that this explicitly limits trace output to line-by-line, it is no longer possible to trace-print just part of a line. Until now, this was just an implicit assumption (trace-printing part of a line worked, but messed up the trace file if multiple threads or processes were involved). Thread-safety / inter-process-safety is also the reason why we need to do the prefixing and suffixing in memory rather than issuing multiple write() calls. Write_or_whine_pipe() / xwrite() is atomic unless the size exceeds MAX_IO_SIZE (8MB, see wrapper.c). In case of trace_strbuf, this costs an additional string copy (which should be irrelevant for performance in light of actual file IO). While we're at it, rename trace_strbuf's 'buf' argument, which suggests that the function is modifying the buffer. Trace_strbuf() currently is the only trace API that can print arbitrary binary data (without barfing on '%' or stopping at '\0'), so 'data' seems more appropriate. Signed-off-by: Karsten Blees <> Signed-off-by: Junio C Hamano <>
2014-07-14trace: improve trace performanceKarsten Blees
The trace API currently rechecks the environment variable and reopens the trace file on every API call. This has the ugly side effect that errors (e.g. file cannot be opened, or the user specified a relative path) are also reported on every call. Performance can be improved by about factor three by remembering the environment state and keeping the file open. Replace the 'const char *key' parameter in the API with a pointer to a 'struct trace_key' that bundles the environment variable name with additional, trace-internal state. Change the call sites of these APIs to use a static 'struct trace_key' instead of a string constant. In trace.c::get_trace_fd(), save and reuse the file descriptor in 'struct trace_key'. Add a 'trace_disable()' API, so that packet_trace() can cleanly disable tracing when it encounters packed data (instead of using unsetenv()). Signed-off-by: Karsten Blees <> Signed-off-by: Junio C Hamano <>
2014-06-17trace: remove redundant printf format attributeKarsten Blees
trace_printf_key() is the only non-static function that duplicates the printf format attribute in the .c file, remove it for consistency. Signed-off-by: Karsten Blees <> Signed-off-by: Junio C Hamano <>
2014-06-17trace: consistently name the format parameterKarsten Blees
The format parameter to trace_printf functions is sometimes abbreviated 'fmt'. Rename to 'format' everywhere (consistent with POSIX' printf specification). Signed-off-by: Karsten Blees <> Signed-off-by: Junio C Hamano <>
2013-12-11shallow.c: the 8 steps to select new commits for .git/shallowNguyễn Thái Ngọc Duy
Suppose a fetch or push is requested between two shallow repositories (with no history deepening or shortening). A pack that contains necessary objects is transferred over together with .git/shallow of the sender. The receiver has to determine whether it needs to update .git/shallow if new refs needs new shallow comits. The rule here is avoid updating .git/shallow by default. But we don't want to waste the received pack. If the pack contains two refs, one needs new shallow commits installed in .git/shallow and one does not, we keep the latter and reject/warn about the former. Even if .git/shallow update is allowed, we only add shallow commits strictly necessary for the former ref (remember the sender can send more shallow commits than necessary) and pay attention not to accidentally cut the receiver history short (no history shortening is asked for) So the steps to figure out what ref need what new shallow commits are: 1. Split the sender shallow commit list into "ours" and "theirs" list by has_sha1_file. Those that exist in current repo in "ours", the remaining in "theirs". 2. Check the receiver .git/shallow, remove from "ours" the ones that also exist in .git/shallow. 3. Fetch the new pack. Either install or unpack it. 4. Do has_sha1_file on "theirs" list again. Drop the ones that fail has_sha1_file. Obviously the new pack does not need them. 5. If the pack is kept, remove from "ours" the ones that do not exist in the new pack. 6. Walk the new refs to answer the question "what shallow commits, both ours and theirs, are required in .git/shallow in order to add this ref?". Shallow commits not associated to any refs are removed from their respective list. 7. (*) Check reachability (from the current refs) of all remaining commits in "ours". Those reachable are removed. We do not want to cut any part of our (reachable) history. We only check up commits. True reachability test is done by check_everything_connected() at the end as usual. 8. Combine the final "ours" and "theirs" and add them all to .git/shallow. Install new refs. The case where some hook rejects some refs on a push is explained in more detail in the push patches. Of these steps, #6 and #7 are expensive. Both require walking through some commits, or in the worst case all commits. And we rather avoid them in at least common case, where the transferred pack does not contain any shallow commits that the sender advertises. Let's look at each scenario: 1) the sender has longer history than the receiver All shallow commits from the sender will be put into "theirs" list at step 1 because none of them exists in current repo. In the common case, "theirs" becomes empty at step 4 and exit early. 2) the sender has shorter history than the receiver All shallow commits from the sender are likely in "ours" list at step 1. In the common case, if the new pack is kept, we could empty "ours" and exit early at step 5. If the pack is not kept, we hit the expensive step 6 then exit after "ours" is emptied. There'll be only a handful of objects to walk in fast-forward case. If it's forced update, we may need to walk to the bottom. 3) the sender has same .git/shallow as the receiver This is similar to case 2 except that "ours" should be emptied at step 2 and exit early. A fetch after "clone --depth=X" is case 1. A fetch after "clone" (from a shallow repo) is case 3. Luckily they're cheap for the common case. A push from "clone --depth=X" falls into case 2, which is expensive. Some more work may be done at the sender/client side to avoid more work on the server side: if the transferred pack does not contain any shallow commits, send-pack should not send any shallow commits to the receive-pack, effectively turning it into a normal push and avoid all steps. This patch implements all steps except #3, already handled by fetch-pack and receive-pack, #6 and #7, which has their own patch due to their size. (*) in previous versions step 7 was put before step 3. I reorder it so that the common case that keeps the pack does not need to walk commits at all. In future if we implement faster commit reachability check (maybe with the help of pack bitmaps or commit cache), step 7 could become cheap and be moved up before 6 again. Signed-off-by: Nguyễn Thái Ngọc Duy <> Signed-off-by: Junio C Hamano <>
2013-07-10add missing "format" function attributesJeff King
For most of our functions that take printf-like formats, we use gcc's __attribute__((format)) to get compiler warnings when the functions are misused. Let's give a few more functions the same protection. In most cases, the annotations do not uncover any actual bugs; the only code change needed is that we passed a size_t to transfer_debug, which expected an int. Since we expect the passed-in value to be a relatively small buffer size (and cast a similar value to int directly below), we can just cast away the problem. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2012-09-16trace.c: mark a private file-scope symbol as staticJunio C Hamano
Signed-off-by: Junio C Hamano <>
2011-03-22Fix sparse warningsStephen Boyd
Fix warnings from 'make check'. - These files don't include 'builtin.h' causing sparse to complain that cmd_* isn't declared: builtin/clone.c:364, builtin/fetch-pack.c:797, builtin/fmt-merge-msg.c:34, builtin/hash-object.c:78, builtin/merge-index.c:69, builtin/merge-recursive.c:22 builtin/merge-tree.c:341, builtin/mktag.c:156, builtin/notes.c:426 builtin/notes.c:822, builtin/pack-redundant.c:596, builtin/pack-refs.c:10, builtin/patch-id.c:60, builtin/patch-id.c:149, builtin/remote.c:1512, builtin/remote-ext.c:240, builtin/remote-fd.c:53, builtin/reset.c:236, builtin/send-pack.c:384, builtin/unpack-file.c:25, builtin/var.c:75 - These files have symbols which should be marked static since they're only file scope: submodule.c:12, diff.c:631, replace_object.c:92, submodule.c:13, submodule.c:14, trace.c:78, transport.c:195, transport-helper.c:79, unpack-trees.c:19, url.c:3, url.c:18, url.c:104, url.c:117, url.c:123, url.c:129, url.c:136, thread-utils.c:21, thread-utils.c:48 - These files redeclare symbols to be different types: builtin/index-pack.c:210, parse-options.c:564, parse-options.c:571, usage.c:49, usage.c:58, usage.c:63, usage.c:72 - These files use a literal integer 0 when they really should use a NULL pointer: daemon.c:663, fast-import.c:2942, imap-send.c:1072, notes-merge.c:362 While we're in the area, clean up some unused #includes in builtin files (mostly exec_cmd.h). Signed-off-by: Stephen Boyd <> Signed-off-by: Junio C Hamano <>
2011-03-08trace: give repo_setup trace its own keyJeff King
You no longer get this output with GIT_TRACE=1; instead, you can do GIT_TRACE_SETUP=1. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2011-03-08trace: add trace_strbufJeff King
If you happen to have a strbuf, it is a little more readable and a little more efficient to be able to print it directly instead of jamming it through the trace_printf interface. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2011-03-08trace: factor out "do we want to trace" logicJeff King
As we add more tracing areas, this will avoid repeated code. Technically, trace_printf already checks this and will avoid printing if the trace key is not set. However, callers may want to find out early whether or not tracing is enabled so they can avoid doing work in the common non-trace case. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2011-03-08trace: refactor to support multiple env variablesJeff King
Right now you turn all tracing off and on with GIT_TRACE. To support new types of tracing without forcing the user to see all of them, we will soon support turning each tracing area on with GIT_TRACE_*. This patch lays the groundwork by providing an interface which does not assume GIT_TRACE. However, we still maintain the trace_printf interface so that existing callers do not need to be refactored. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2011-03-08trace: add trace_vprintfJeff King
This is a necessary cleanup to adding new types of trace functions. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2011-02-26strbuf: add strbuf_vaddfJeff King
In a variable-args function, the code for writing into a strbuf is non-trivial. We ended up cutting and pasting it in several places because there was no vprintf-style function for strbufs (which in turn was held up by a lack of va_copy). Now that we have a fallback va_copy, we can add strbuf_vaddf, the strbuf equivalent of vsprintf. And we can clean up the cut and paste mess. Signed-off-by: Jeff King <> Improved-by: Christian Couder <> Signed-off-by: Jonathan Nieder <> Signed-off-by: Junio C Hamano <>