We grab the lock while accessing the alternates list, ensuring that
we only initialize it once for the given git_odb.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

These abstractions can be used to implement an efficient resource
reference counter and simple mutual exclusion.  On pthreads we use
pthread_mutex_t, except when we are also on glibc and can directly
use its asm/atomic.h definitions.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

If we are using threads we need to make sure pthread.h comes
in before just about anything else.  Some platforms enable
macros that alter what other headers define.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

This way we can be fairly certain we run tests of lower-level
parts of the library before we run tests of higher-level more
complex parts.  If there is any problem in a lower-level part
of the library, the earlier test will identify it and stop,
making it easire to troubleshoot the failure.

A rough naming guide has been added for the test suite to
explain the current category structure.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Some systems may use cpp macros to define these functions, glibc
appears to be one of them.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

This error code indicates the OS error code has a better value
describing the last error, as it is likely a network or local
file IO problem identified by a C library function call.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

We now forbid direct use of malloc, strdup or calloc within the
library and instead use wrapper functions git__malloc, etc. to
invoke the underlying library malloc and set git_errno to a no
memory error code if the allocation fails.

In the future once we have pack objects in memory we are likely
to enhance these routines with garbage collection logic to purge
cached pack data when allocations fail.  Because the size of the
function will grow somewhat large, we don't want to mark them for
inline as gcc tends to aggressively inline, creating larger than
expected executables.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

We're likely to add additional path data, like the path of the
refs or the path to the config file into the git_odb structure,
as it may grow into the repository wrapper.  Changing the name
of the objects directory reference makes it more clear should
we later add something else.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

We didn't search for the object, so we cannot possibly promise it
to the caller of git_odb_read().

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

This is the correct C99 format code for the size_t type when passed
as an argument to the *printf family.  If the platform doesn't
define it, we assume %lu and just cross our fingers that its the
proper setting for a size_t on this system.  On most sane platforms,
"unsigned long" is the underlying type of "size_t".

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

The Mach-O format does not permit gcc to implement the __thread
TLS specification, so we must instead emulate it using a single
int cell allocated from memory and stored inside of the thread
specific data associated with the current pthread.

What makes this tricky is git_errno must be a valid lvalue, so
we really need to return a pointer to the caller and deference it
as part of the git_errno macro.

The GCC-specific __attribute__((constructor)) extension is used
to ensure the pthread_key_t is allocated before any Git functions
are executed in the library, as this is necessary to access our
thread specific storage.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

OS headers are best imported from a more central location anyway.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Signed-off-by: Julio Espinoza-Sokal <julioes@gmail.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

libz and libcrypto dependencies were added recently while libgit2.pc
did not get updated.

Signed-off-by: Steve Frécinaux <code@istique.net>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

[sp: Changed signature for output to use git_oid, and added
     a test case to verify an allocated git_hash_ctx can be
     reinitialized and reused.]

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

In particular, when asked to read an empty file, this function
calls malloc() with a zero size allocation request. Standard C
says that the behaviour of malloc() in this case is implementation
defined.

[C99, 7.20.3 says "... If the size of the space requested is zero,
the behavior is implementation-defined: either a null pointer is
returned, or the behavior is as if the size were some nonzero
value, except that the returned pointer shall not be used to
access an object."]

Finesse the issue by over-allocating by one byte. Setting the extra
byte to '\0' may also provide a useful sentinel for text files.

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

The libgit2.pc is generated on make install and installed, to allow
using the lib through the pkg-config helper.

Signed-off-by: Steve Frécinaux <code@istique.net>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

It accepts a prefix= parameter (default: /usr/local).

Signed-off-by: Steve Frécinaux <code@istique.net>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

In particular, the gitfo_read_file() routine can be used to slurp
the complete file contents into an gitfo_buf structure. The buffer
content will be allocated by malloc() and may be released by the
gitfo_free_buf() routine. The io buffer type can be initialised
on the stack with the GITFO_BUF_INIT macro.

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

It was removed in ec250c6e.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

This way tests can run in parallel without stepping on each other's
temporary work files.  If a test passes the directory is removed
completely; if a test fails only empty directories are removed.
This permits inspection of the failed test's left behind state.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

In particular, the warning relates to malloc(), which is
declared in <stdlib.h>.  This header is now included,
indirectly, via the "common.h" header.

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

The PATH_MAX symbol is often, but not always, defined
in the <limits.h> header.  In particular, on cygwin you
need to include this header to avoid a compilation error.

However, some systems define PATH_MAX to be something as
small as 256, which POSIX is happy to allow, while others
allow much larger values.  In general it can vary from
one filesystem to another.

In order to avoid the vagaries of different systems, define
our own symbol.

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Signed-off-by: Andreas Ericsson <ae@op5.se>

[sp: Credit for some of this implementation goes to Pieter, I
     started off a patch he proposed for libgit2 but reworked
     enough of it that I don't want to blame him for any bugs.]

Suggested-by: Pieter de Bie <pdebie@ai.rug.nl>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Acked-by: Andreas Ericsson <ae@op5.se>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Acked-by: Andreas Ericsson <ae@op5.se>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

cgcc is the recommended way to run sparse, since it provides
many -Defines suitable to the given gcc platform. For example,
on some Ubuntu/glibc versions, a plain sparse invocation gives
the following warning:

    "warning: This machine appears to be neither x86_64 nor i386."

Using "cgcc -no-compile" instead eliminates this warning.

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Acked-by: Andreas Ericsson <ae@op5.se>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

commit dff79e27 renamed
the (small object) "git_sobj" to a plain "git_obj", but
neglected to update some of the documentation to reflect
that change.

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Since at least MS have something like GetFirstDirEnt() and
GetNextDirEnt() (presumably with superior performance), we
can let MS hackers add support for a dirent walker using
that API instead, while we stick with the posix-style
readdir() calls.

Signed-off-by: Andreas Ericsson <ae@op5.se>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

The idea is taken from Junio's work in read-cache.c, where
it's used for writing out the index without tap-dancing on
the poor harddrive. Since it's almost certainly useful for
cached writing of packfiles too, we turn it into a generic
API, making it perfectly simple to reuse it later.

gitfo_write_cached() has the same contract as gitfo_write(), it
returns GIT_SUCCESS if all bytes are successfully written (or were
at least buffered for later writing), and <0 if an error occurs
during buffer writing.

Signed-off-by: Andreas Ericsson <ae@op5.se>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Since it doesn't make sense to make the disk access stuff
portable *AND* public (that's a job for each application
imo), we can take a shortcut and just support unixy stuff
for now and get away with coding most of it as macros.

Since we go with an internal API for starters and only
provide higher-level API's to the libgit users, we'll be
ok with this approach.

Signed-off-by: Andreas Ericsson <ae@op5.se>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

In d4043ee9, public headers
were moved from include/git to src/git, but the doxygen
configuration wasn't updated to reflect this. This patch
amends that slippage, making documentation generation once
again work as intended.

Signed-off-by: Andreas Ericsson <ae@op5.se>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

This is to be used for application code that currently
resides in git, but only for authors whose only not
insignificant contributions are for that code (such as
"imap-send").

Presently, this is used for Mike McCormack and Robert
Shearman.

Signed-off-by: Andreas Ericsson <ae@op5.se>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Signed-off-by: Andreas Ericsson <ae@op5.se>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>