<feed xmlns='http://www.w3.org/2005/Atom'>
<title>git/strbuf.c, branch v2.45.2</title>
<subtitle>Mirror of https://git.kernel.org/pub/scm/git/git.git/
</subtitle>
<id>https://git.shady.money/git/atom?h=v2.45.2</id>
<link rel='self' href='https://git.shady.money/git/atom?h=v2.45.2'/>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/'/>
<updated>2024-04-21T19:27:07Z</updated>
<entry>
<title>don't report vsnprintf(3) error as bug</title>
<updated>2024-04-21T19:27:07Z</updated>
<author>
<name>René Scharfe</name>
<email>l.s.r@web.de</email>
</author>
<published>2024-04-21T12:40:28Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=0283cd5161561b29951c00697679c10b454e541a'/>
<id>urn:sha1:0283cd5161561b29951c00697679c10b454e541a</id>
<content type='text'>
strbuf_addf() has been reporting a negative return value of vsnprintf(3)
as a bug since f141bd804d (Handle broken vsnprintf implementations in
strbuf, 2007-11-13).  Other functions copied that behavior:

7b03c89ebd (add xsnprintf helper function, 2015-09-24)
5ef264dbdb (strbuf.c: add `strbuf_insertf()` and `strbuf_vinsertf()`, 2019-02-25)
8d25663d70 (mem-pool: add mem_pool_strfmt(), 2024-02-25)

However, vsnprintf(3) can legitimately return a negative value if the
formatted output would be longer than INT_MAX.  Stop accusing it of
being broken and just report the fact that formatting failed.

Suggested-by: Jeff King &lt;peff@peff.net&gt;
Signed-off-by: René Scharfe &lt;l.s.r@web.de&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
</content>
</entry>
<entry>
<title>Merge branch 'jk/core-comment-string'</title>
<updated>2024-04-05T17:49:49Z</updated>
<author>
<name>Junio C Hamano</name>
<email>gitster@pobox.com</email>
</author>
<published>2024-04-05T17:49:49Z</published>
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<id>urn:sha1:dce1e0b6daaa872a3b88724d9aa1b087c95e8754</id>
<content type='text'>
core.commentChar used to be limited to a single byte, but has been
updated to allow an arbitrary multi-byte sequence.

* jk/core-comment-string:
  config: add core.commentString
  config: allow multi-byte core.commentChar
  environment: drop comment_line_char compatibility macro
  wt-status: drop custom comment-char stringification
  sequencer: handle multi-byte comment characters when writing todo list
  find multi-byte comment chars in unterminated buffers
  find multi-byte comment chars in NUL-terminated strings
  prefer comment_line_str to comment_line_char for printing
  strbuf: accept a comment string for strbuf_add_commented_lines()
  strbuf: accept a comment string for strbuf_commented_addf()
  strbuf: accept a comment string for strbuf_stripspace()
  environment: store comment_line_char as a string
  strbuf: avoid shadowing global comment_line_char name
  commit: refactor base-case of adjust_comment_line_char()
  strbuf: avoid static variables in strbuf_add_commented_lines()
  strbuf: simplify comment-handling in add_lines() helper
  config: forbid newline as core.commentChar
</content>
</entry>
<entry>
<title>factor out strbuf_expand_bad_format()</title>
<updated>2024-03-25T18:59:24Z</updated>
<author>
<name>René Scharfe</name>
<email>l.s.r@web.de</email>
</author>
<published>2024-03-24T11:19:40Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=e36091aa1d67cedba02ea9de9245f0ff14a52f15'/>
<id>urn:sha1:e36091aa1d67cedba02ea9de9245f0ff14a52f15</id>
<content type='text'>
Extract a function for reporting placeholders that are not enclosed in a
parenthesis or are unknown.  This reduces the number of strings to
translate and improves consistency across commands.  Call it at the end
of the if/else chain, after exhausting all accepted possibilities.

Signed-off-by: René Scharfe &lt;l.s.r@web.de&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
</content>
</entry>
<entry>
<title>find multi-byte comment chars in unterminated buffers</title>
<updated>2024-03-12T20:28:10Z</updated>
<author>
<name>Jeff King</name>
<email>peff@peff.net</email>
</author>
<published>2024-03-12T09:17:39Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=2ec225d397d564d9c6bb907d85a58507dec75989'/>
<id>urn:sha1:2ec225d397d564d9c6bb907d85a58507dec75989</id>
<content type='text'>
As with the previous patch, we need to swap out single-byte matching for
something like starts_with() to match all bytes of a multi-byte comment
character. But for cases where the buffer is not NUL-terminated (and we
instead have an explicit size or end pointer), it's not safe to use
starts_with(), as it might walk off the end of the buffer.

Let's introduce a new starts_with_mem() that does the same thing but
also accepts the length of the "haystack" str and makes sure not to walk
past it.

Note that in most cases the existing code did not need a length check at
all, since it was written in a way that knew we had at least one byte
available (and that was all we checked). So I had to read each one to
find the appropriate bounds. The one exception is sequencer.c's
add_commented_lines(), where we can actually get rid of the length
check. Just like starts_with(), our starts_with_mem() handles an empty
haystack variable by not matching (assuming a non-empty prefix).

A few notes on the implementation of starts_with_mem():

  - it would be equally correct to take an "end" pointer (and indeed,
    many of the callers have this and have to subtract to come up with
    the length). I think taking a ptr/size combo is a more usual
    interface for our codebase, though, and has the added benefit that
    the function signature makes it harder to mix up the three
    parameters.

  - we could obviously build starts_with() on top of this by passing
    strlen(str) as the length. But it's possible that starts_with() is a
    relatively hot code path, and it should not pay that penalty (it can
    generally return an answer proportional to the size of the prefix,
    not the whole string).

  - it naively feels like xstrncmpz() should be able to do the same
    thing, but that's not quite true. If you pass the length of the
    haystack buffer, then strncmp() finds that a shorter prefix string
    is "less than" than the haystack, even if the haystack starts with
    the prefix. If you pass the length of the prefix, then you risk
    reading past the end of the haystack if it is shorter than the
    prefix. So I think we really do need a new function.

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>strbuf: accept a comment string for strbuf_add_commented_lines()</title>
<updated>2024-03-12T20:28:10Z</updated>
<author>
<name>Jeff King</name>
<email>peff@peff.net</email>
</author>
<published>2024-03-12T09:17:32Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=a1bb146aaf551db4ff9b4aafaaa2f7a9f9574f93'/>
<id>urn:sha1:a1bb146aaf551db4ff9b4aafaaa2f7a9f9574f93</id>
<content type='text'>
As part of our transition to multi-byte comment characters, let's take a
NUL-terminated string pointer for strbuf_add_commented_lines() rather
than a single character.

All of the callers have to be adjusted; most can just pass
comment_line_str rather than comment_line_char.

And now our "cheat" in strbuf_commented_addf() can go away, as we can
take the full string from it.

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>strbuf: accept a comment string for strbuf_commented_addf()</title>
<updated>2024-03-12T20:28:10Z</updated>
<author>
<name>Jeff King</name>
<email>peff@peff.net</email>
</author>
<published>2024-03-12T09:17:29Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=3a35d96284b4a0551a350707df68f368947630d1'/>
<id>urn:sha1:3a35d96284b4a0551a350707df68f368947630d1</id>
<content type='text'>
As part of our transition to multi-byte comment characters, let's take a
NUL-terminated string pointer for strbuf_commented_addf() rather than a
single character.

All of the callers have to be adjusted, but they can just pass
comment_line_str rather than comment_line_char.

Note that we rely on strbuf_add_commented_lines() under the hood, so
we'll cheat a bit to squeeze our string into a single character (for now
the two are equivalent, and we'll address this TODO in the next patch).

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>strbuf: accept a comment string for strbuf_stripspace()</title>
<updated>2024-03-12T20:28:10Z</updated>
<author>
<name>Jeff King</name>
<email>peff@peff.net</email>
</author>
<published>2024-03-12T09:17:27Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=2982b65690d7a043275558c74202a89b0450cbf5'/>
<id>urn:sha1:2982b65690d7a043275558c74202a89b0450cbf5</id>
<content type='text'>
As part of our transition to multi-byte comment characters, let's take a
NUL-terminated string pointer for strbuf_stripspace(), rather than a
single character. We can continue to support its feature of ignoring
comments by accepting a NULL pointer (as opposed to the current behavior
of a NUL byte).

All of the callers have to be adjusted, but they can all just pass
comment_line_str (or NULL).

Inside the function we detect comments by comparing the first byte of a
line to the comment character. We'll adjust that to use starts_with(),
which will match multiple bytes (though for now, of course, we still
only allow a single byte, so it's academic).

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>strbuf: avoid shadowing global comment_line_char name</title>
<updated>2024-03-12T20:28:10Z</updated>
<author>
<name>Jeff King</name>
<email>peff@peff.net</email>
</author>
<published>2024-03-12T09:17:22Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=2786d058b6b25ab5f8d0994d24f4f4dc9442a41a'/>
<id>urn:sha1:2786d058b6b25ab5f8d0994d24f4f4dc9442a41a</id>
<content type='text'>
Several comment-related strbuf functions take a comment_line_char
parameter. There's also a global comment_line_char variable, which is
closely related (most callers pass it in as this parameter). Let's avoid
shadowing the global name. This makes it more obvious that we're not
using the global value, and it will be especially helpful as we refactor
the global in future patches (in particular, any macro trickery wouldn't
work because the preprocessor doesn't respect scope).

We'll use "comment_prefix". That should be descriptive enough, and as a
bonus is more neutral with respect to the "char" type (since we'll
eventually swap it out for a string).

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>strbuf: avoid static variables in strbuf_add_commented_lines()</title>
<updated>2024-03-12T20:28:09Z</updated>
<author>
<name>Jeff King</name>
<email>peff@peff.net</email>
</author>
<published>2024-03-12T09:17:15Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=3b45450db65b97f010420229457c529f69bb2168'/>
<id>urn:sha1:3b45450db65b97f010420229457c529f69bb2168</id>
<content type='text'>
In strbuf_add_commented_lines(), we have to convert the single-byte
comment_line_char into a string to pass to add_lines(). We cache the
created string using a static-local variable. But this makes the
function non-reentrant, and it's doubtful that this provides any real
performance benefit given that we know the string always contains a
single character.

So let's just create it from scratch each time, and to give the compiler
the maximal opportunity to make it fast we'll ditch the over-complicated
xsnprintf() and just assign directly into 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>strbuf: simplify comment-handling in add_lines() helper</title>
<updated>2024-03-12T20:28:09Z</updated>
<author>
<name>Jeff King</name>
<email>peff@peff.net</email>
</author>
<published>2024-03-12T09:17:10Z</published>
<link rel='alternate' type='text/html' href='https://git.shady.money/git/commit/?id=db7f93093f2231a922c3d58e7ef5135168e7bb80'/>
<id>urn:sha1:db7f93093f2231a922c3d58e7ef5135168e7bb80</id>
<content type='text'>
In strbuf_add_commented_lines(), we prepare two strings with potential
prefixes: one with just the comment char, and one with an additional
space. In the add_lines() helper, we use the one without the extra space
for blank lines or lines starting with a tab.

While passing in two separate prefixes to the helper is very flexible,
it's more flexibility than we actually use (or are likely to use, since
the rules inside add_lines() only make sense if "prefix2" is a variant
of "prefix1" without the extra space). And setting up the two strings
makes refactoring in strbuf_add_commented_lines() awkward.

Instead, let's pass in a single string, and just let add_lines() add the
extra space to the result as appropriate.

We do still need to pass in a flag to trigger this behavior. The helper
is shared by strbuf_add_lines(), which passes in a NULL "prefix2" to
inhibit this extra handling.

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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