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<title>git/combine-diff.c, branch v2.9.2</title>
<subtitle>Mirror of https://git.kernel.org/pub/scm/git/git.git/
</subtitle>
<id>https://git.shady.money/git/atom?h=v2.9.2</id>
<link rel='self' href='https://git.shady.money/git/atom?h=v2.9.2'/>
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<updated>2016-05-09T19:29:08Z</updated>
<entry>
<title>combine-diff.c: use error_errno()</title>
<updated>2016-05-09T19:29:08Z</updated>
<author>
<name>Nguyễn Thái Ngọc Duy</name>
<email>pclouds@gmail.com</email>
</author>
<published>2016-05-08T09:47:36Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=4b94ec9b200e9bafc5fd2c9c4e8b7e7934d60c00'/>
<id>urn:sha1:4b94ec9b200e9bafc5fd2c9c4e8b7e7934d60c00</id>
<content type='text'>
Signed-off-by: Nguyễn Thái Ngọc Duy &lt;pclouds@gmail.com&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
</content>
</entry>
<entry>
<title>use st_add and st_mult for allocation size computation</title>
<updated>2016-02-22T22:51:09Z</updated>
<author>
<name>Jeff King</name>
<email>peff@peff.net</email>
</author>
<published>2016-02-22T22:44:35Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=50a6c8efa2bbeddf46ca34c7765024108202e04b'/>
<id>urn:sha1:50a6c8efa2bbeddf46ca34c7765024108202e04b</id>
<content type='text'>
If our size computation overflows size_t, we may allocate a
much smaller buffer than we expected and overflow it. It's
probably impossible to trigger an overflow in most of these
sites in practice, but it is easy enough convert their
additions and multiplications into overflow-checking
variants. This may be fixing real bugs, and it makes
auditing the code easier.

Signed-off-by: Jeff King &lt;peff@peff.net&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
</content>
</entry>
<entry>
<title>convert trivial cases to FLEX_ARRAY macros</title>
<updated>2016-02-22T22:51:09Z</updated>
<author>
<name>Jeff King</name>
<email>peff@peff.net</email>
</author>
<published>2016-02-22T22:44:32Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=96ffc06f72f693d80f05059a1f0e5ca9007d5f1b'/>
<id>urn:sha1:96ffc06f72f693d80f05059a1f0e5ca9007d5f1b</id>
<content type='text'>
Using FLEX_ARRAY macros reduces the amount of manual
computation size we have to do. It also ensures we don't
overflow size_t, and it makes sure we write the same number
of bytes that we allocated.

Signed-off-by: Jeff King &lt;peff@peff.net&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
</content>
</entry>
<entry>
<title>use xmallocz to avoid size arithmetic</title>
<updated>2016-02-22T22:51:09Z</updated>
<author>
<name>Jeff King</name>
<email>peff@peff.net</email>
</author>
<published>2016-02-22T22:44:28Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=3733e6946465d4a3a1d89026a5ec911d3af339ab'/>
<id>urn:sha1:3733e6946465d4a3a1d89026a5ec911d3af339ab</id>
<content type='text'>
We frequently allocate strings as xmalloc(len + 1), where
the extra 1 is for the NUL terminator. This can be done more
simply with xmallocz, which also checks for integer
overflow.

There's no case where switching xmalloc(n+1) to xmallocz(n)
is wrong; the result is the same length, and malloc made no
guarantees about what was in the buffer anyway. But in some
cases, we can stop manually placing NUL at the end of the
allocated buffer. But that's only safe if it's clear that
the contents will always fill the buffer.

In each case where this patch does so, I manually examined
the control flow, and I tried to err on the side of caution.

Signed-off-by: Jeff King &lt;peff@peff.net&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
</content>
</entry>
<entry>
<title>convert trivial cases to ALLOC_ARRAY</title>
<updated>2016-02-22T22:51:09Z</updated>
<author>
<name>Jeff King</name>
<email>peff@peff.net</email>
</author>
<published>2016-02-22T22:44:25Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=b32fa95fd8293ebfecb2b7b6c8d460579318f9fe'/>
<id>urn:sha1:b32fa95fd8293ebfecb2b7b6c8d460579318f9fe</id>
<content type='text'>
Each of these cases can be converted to use ALLOC_ARRAY or
REALLOC_ARRAY, which has two advantages:

  1. It automatically checks the array-size multiplication
     for overflow.

  2. It always uses sizeof(*array) for the element-size,
     so that it can never go out of sync with the declared
     type of the array.

Signed-off-by: Jeff King &lt;peff@peff.net&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
</content>
</entry>
<entry>
<title>Remove get_object_hash.</title>
<updated>2015-11-20T13:02:05Z</updated>
<author>
<name>brian m. carlson</name>
<email>sandals@crustytoothpaste.net</email>
</author>
<published>2015-11-10T02:22:29Z</published>
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<id>urn:sha1:ed1c9977cb1b63e4270ad8bdf967a2d02580aa08</id>
<content type='text'>
Convert all instances of get_object_hash to use an appropriate reference
to the hash member of the oid member of struct object.  This provides no
functional change, as it is essentially a macro substitution.

Signed-off-by: brian m. carlson &lt;sandals@crustytoothpaste.net&gt;
Signed-off-by: Jeff King &lt;peff@peff.net&gt;
</content>
</entry>
<entry>
<title>Add several uses of get_object_hash.</title>
<updated>2015-11-20T13:02:05Z</updated>
<author>
<name>brian m. carlson</name>
<email>sandals@crustytoothpaste.net</email>
</author>
<published>2015-11-10T02:22:27Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=7999b2cf772956466baa8925491d6fb1b0963292'/>
<id>urn:sha1:7999b2cf772956466baa8925491d6fb1b0963292</id>
<content type='text'>
Convert most instances where the sha1 member of struct object is
dereferenced to use get_object_hash.  Most instances that are passed to
functions that have versions taking struct object_id, such as
get_sha1_hex/get_oid_hex, or instances that can be trivially converted
to use struct object_id instead, are not converted.

Signed-off-by: brian m. carlson &lt;sandals@crustytoothpaste.net&gt;
Signed-off-by: Jeff King &lt;peff@peff.net&gt;
</content>
</entry>
<entry>
<title>Sync with 2.4.10</title>
<updated>2015-09-28T22:33:56Z</updated>
<author>
<name>Junio C Hamano</name>
<email>gitster@pobox.com</email>
</author>
<published>2015-09-28T22:33:56Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=11a458befcd7662fbe6d2d53c76d49ae2b0fe219'/>
<id>urn:sha1:11a458befcd7662fbe6d2d53c76d49ae2b0fe219</id>
<content type='text'>
</content>
</entry>
<entry>
<title>Sync with 2.3.10</title>
<updated>2015-09-28T22:28:31Z</updated>
<author>
<name>Junio C Hamano</name>
<email>gitster@pobox.com</email>
</author>
<published>2015-09-28T22:28:26Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=6343e2f6f271cf344ea8e7384342502faecaf37c'/>
<id>urn:sha1:6343e2f6f271cf344ea8e7384342502faecaf37c</id>
<content type='text'>
</content>
</entry>
<entry>
<title>react to errors in xdi_diff</title>
<updated>2015-09-28T21:57:10Z</updated>
<author>
<name>Jeff King</name>
<email>peff@peff.net</email>
</author>
<published>2015-09-24T23:12:23Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=3efb988098858bf6b974b1e673a190f9d2965d1d'/>
<id>urn:sha1:3efb988098858bf6b974b1e673a190f9d2965d1d</id>
<content type='text'>
When we call into xdiff to perform a diff, we generally lose
the return code completely. Typically by ignoring the return
of our xdi_diff wrapper, but sometimes we even propagate
that return value up and then ignore it later.  This can
lead to us silently producing incorrect diffs (e.g., "git
log" might produce no output at all, not even a diff header,
for a content-level diff).

In practice this does not happen very often, because the
typical reason for xdiff to report failure is that it
malloc() failed (it uses straight malloc, and not our
xmalloc wrapper).  But it could also happen when xdiff
triggers one our callbacks, which returns an error (e.g.,
outf() in builtin/rerere.c tries to report a write failure
in this way). And the next patch also plans to add more
failure modes.

Let's notice an error return from xdiff and react
appropriately. In most of the diff.c code, we can simply
die(), which matches the surrounding code (e.g., that is
what we do if we fail to load a file for diffing in the
first place). This is not that elegant, but we are probably
better off dying to let the user know there was a problem,
rather than simply generating bogus output.

We could also just die() directly in xdi_diff, but the
callers typically have a bit more context, and can provide a
better message (and if we do later decide to pass errors up,
we're one step closer to doing so).

There is one interesting case, which is in diff_grep(). Here
if we cannot generate the diff, there is nothing to match,
and we silently return "no hits". This is actually what the
existing code does already, but we make it a little more
explicit.

Signed-off-by: Jeff King &lt;peff@peff.net&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
</content>
</entry>
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