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Author SHA1 Message Date
Junio C Hamano
fde1cc1dc2 Merge branch 'jn/vcs-svn'
vcs-svn updates to clean-up compilation, lift 32-bit limitations, etc.

* jn/vcs-svn:
  vcs-svn: allow 64-bit Prop-Content-Length
  vcs-svn: suppress a signed/unsigned comparison warning
  vcs-svn: suppress a signed/unsigned comparison warning
  vcs-svn: suppress signed/unsigned comparison warnings
  vcs-svn: use strstr instead of memmem
  vcs-svn: use constcmp instead of prefixcmp
  vcs-svn: simplify cleanup in apply_one_window
  vcs-svn: avoid self-assignment in dummy initialization of pre_off
  vcs-svn: drop no-op reset methods
  vcs-svn: suppress -Wtype-limits warning
  vcs-svn: allow import of > 4GiB files
  vcs-svn: rename check_overflow and its arguments for clarity
2012-07-13 15:37:04 -07:00
Jonathan Nieder
e32b79cb32 vcs-svn: allow 64-bit Prop-Content-Length
Currently the vcs-svn/ library only pays attention to the presence of
the Prop-Content-Length field and doesn't care about its value, but
some day we might care about the value.  Parse it as an off_t instead
of arbitrarily limiting to 32 bits for intuitiveness.

So now you can import from a dump with more than 2 GiB of properties
for a node.  In practice that isn't likely to happen often, and this
is mostly meant as a cleanup.

Based-on-patch-by: David Barr <davidbarr@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2012-07-05 23:26:53 -05:00
Jonathan Nieder
96a60a8709 vcs-svn: suppress a signed/unsigned comparison warning
All callers pass a nonnegative delta_len, so the code is already safe.
Add an assertion to ensure that remains so and add a cast to keep
clang and gcc -Wsign-compare from worrying.

Reported-by: David Barr <davidbarr@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2012-07-05 23:26:53 -05:00
David Barr
c68038effe vcs-svn: suppress a signed/unsigned comparison warning
The preceding code checks that view->max_off is nonnegative and
(off + width) fits in an off_t, so this code is already safe.

Signed-off-by: David Barr <davidbarr@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2012-07-05 23:26:53 -05:00
David Barr
6a0b4438af vcs-svn: suppress signed/unsigned comparison warnings
These are already safe because both sides of the comparison are
nonnegative.

This would normally not be important because Git is not -Wsign-compare
clean anyway, but we like to keep the vcs-svn/ lib to a higher
standard for convenience using it in other projects.

Signed-off-by: David Barr <davidbarr@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2012-07-05 23:26:53 -05:00
David Barr
53153e8382 vcs-svn: use strstr instead of memmem
memmem is a GNU extension.

Avoiding it makes the code clearer and makes it easier for projects
that don't share git's compat/ code, such as the standalone
svn-dump-fast-export project, to reuse the vcs-svn/ library.

Signed-off-by: David Barr <davidbarr@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2012-07-05 23:26:52 -05:00
David Barr
d8d8708bd6 vcs-svn: use constcmp instead of prefixcmp
Since the length of t is already known, we can simplify a little by
using memcmp() instead of strncmp() to carry out a prefix comparison.
All nearby code already does this.

Noticed in the standalone svn-dump-fast-export project which has not
needed to implement prefixcmp() yet.

Signed-off-by: David Barr <davidbarr@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2012-07-05 23:26:52 -05:00
David Barr
4a1613194a vcs-svn: simplify cleanup in apply_one_window
Currently the cleanup code looks like this:

	free resources
	return 0;
 error_out:
	free resources
	return -1;

Avoid duplicating the "free resources" part by keeping the return
value in a variable and sharing code between the success and
exceptional case:

	ret = 0;
 out:
	free resources
	return ret;

Noticed in the svn-dump-fast-export project, where using the error()
macro in void context produces a warning.

Signed-off-by: David Barr <davidbarr@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2012-07-05 23:26:52 -05:00
David Barr
4a5de8dd79 vcs-svn: avoid self-assignment in dummy initialization of pre_off
Without this change, clang complains:

 vcs-svn/svndiff.c:298:3: warning: Assigned value is garbage or undefined
                 off_t pre_off = pre_off; /* stupid GCC... */
                 ^               ~~~~~~~

This code uses an old and common idiom for suppressing an
"uninitialized variable" warning, and clang is wrong to warn about it.
The idiom tells the compiler to leave the variable uninitialized,
which saves a few bytes of code size, and, more importantly, allows
valgrind to check at runtime that the variable is properly initialized
by the time it is used.

But MSVC and clang do not know that idiom, so let's avoid it in
vcs-svn/ code.

Initialize pre_off to -1, a recognizably meaningless value, to allow
future code changes that cause pre_off to be used before it is
initialized to be caught early.

Signed-off-by: David Barr <davidbarr@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2012-07-05 23:26:52 -05:00
David Barr
3b8a305173 vcs-svn: drop no-op reset methods
Since v1.7.5~42^2~6 (vcs-svn: remove buffer_read_string)
buffer_reset() does nothing thus fast_export_reset() also.

Signed-off-by: David Barr <davidbarr@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2012-07-05 23:26:51 -05:00
Pete Wyckoff
82247e9bd5 remove superfluous newlines in error messages
The error handling routines add a newline.  Remove
the duplicate ones in error messages.

Signed-off-by: Pete Wyckoff <pw@padd.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-04-30 15:45:51 -07:00
Jonathan Nieder
3f790003a3 vcs-svn: suppress a -Wtype-limits warning
On 32-bit architectures with 64-bit file offsets, gcc 4.3 and earlier
produce the following warning:

	    CC vcs-svn/sliding_window.o
	vcs-svn/sliding_window.c: In function `check_overflow':
	vcs-svn/sliding_window.c:36: warning: comparison is always false \
	    due to limited range of data type

The warning appears even when gcc is run without any warning flags
(this is gcc bug 12963).  In later versions the same warning can be
reproduced with -Wtype-limits, which is implied by -Wextra.

On 64-bit architectures it really is possible for a size_t not to be
representable as an off_t so the check this is warning about is not
actually redundant.  But even false positives are distracting.  Avoid
the warning by making the "len" argument to check_overflow a
uintmax_t; no functional change intended.

Reported-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-02 11:05:18 -08:00
Jonathan Nieder
150f75467c vcs-svn: allow import of > 4GiB files
There is no reason in principle that an svn-format dump would not be
able to represent a file whose length does not fit in a 32-bit
integer.  Use off_t consistently to represent file lengths (in place
of using uint32_t in some contexts) so we can handle that.

Most svn-fe code is already ready to do that without this patch and
passes values of type off_t around.  The type mismatch from stragglers
was noticed with gcc -Wtype-limits.

While at it, tighten the parsing of the Text-content-length field to
make sure it is a number and does not overflow, and tighten other
overflow checks as that value is passed around and manipulated.

Inspired-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-02 11:03:30 -08:00
Ramsay Jones
173223aa62 vcs-svn: rename check_overflow arguments for clarity
Code using the argument names a and b just doesn't look right (not
sure why!).  Use more explicit names "offset" and "len" to make their
type and meaning clearer.

Also rename check_overflow() to check_offset_overflow() to clarify
that we are making sure that "len" bytes beyond "offset" still fits
the type to represent an offset.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-02 10:53:18 -08:00
Jonathan Nieder
5b8bf02930 vcs-svn: suppress -Wtype-limits warning
On 32-bit architectures with 64-bit file offsets, gcc 4.3 and earlier
produce the following warning:

	    CC vcs-svn/sliding_window.o
	vcs-svn/sliding_window.c: In function `check_overflow':
	vcs-svn/sliding_window.c:36: warning: comparison is always false \
	    due to limited range of data type

The warning appears even when gcc is run without any warning flags
(PR12963).  In later versions it can be reproduced with -Wtype-limits,
which is implied by -Wextra.

On 64-bit architectures it really is possible for a size_t not to be
representable as an off_t so the check being warned about is not
actually redundant.  But even false positives are distracting.  Avoid
the warning by making the "len" argument to check_overflow a
uintmax_t; no functional change intended.

Reported-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2012-02-02 05:33:37 -06:00
Jonathan Nieder
2d54b9ea8b vcs-svn: allow import of > 4GiB files
There is no reason in principle that an svn-format dump would not
be able to represent a file whose length does not fit in a 32-bit
integer.  Use off_t consistently (instead of uint32_t) to represent
file lengths so we can handle that.

Most of our code is already ready to do that without this patch and
already passes values of type off_t around.  The type mismatch due to
stragglers was noticed with gcc -Wtype-limits.

Inspired-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2012-02-02 05:33:13 -06:00
Ramsay Jones
ce8ebcdaf3 vcs-svn: rename check_overflow and its arguments for clarity
The canonical interpretation of a range a,b is as an interval [a,b),
not [a,a+b), so this function taking argument names a and b feels
unnatural.  Use more explicit names "offset" and "len" to make the
arguments' type and function clearer.

While at it, rename the function to convey that we are making sure
the sum of this offset and length do not overflow an off_t, not a
size_t.

[jn: split out from a patch from Ramsay Jones, then improved with
 advice from Thomas Rast, Dmitry Ivankov, and David Barr]

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Improved-by: Dmitry Ivankov <divanorama@gmail.com>
2012-02-02 05:28:51 -06:00
Junio C Hamano
58ebd9865d vcs-svn/svndiff.c: squelch false "unused" warning from gcc
Curiously, pre_len given to read_length() does not trigger the same warning
even though the code structure is the same. Most likely this is because
read_offset() is used only once and inlining it will make gcc realize that
it has a chance to do more flow analysis. Alas, the analysis is flawed, so
it does not help X-<.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-01-27 11:58:56 -08:00
Junio C Hamano
d475536658 Merge branch 'svn-fe' of git://repo.or.cz/git/jrn into jn/svn-fe
This simplifies svn-fe a great deal and fulfills a longstanding wish:
support for dumps with deltas in them, and incremental imports.

The cost is that commandline usage of the svn-fe tool becomes a little
more complicated since it no longer keeps state itself but instead reads
blobs back from fast-import in order to copy them between revisions and
apply deltas to them.

Also removes a couple of custom data structures and replaces them with
strbufs like other parts of Git.

* 'svn-fe' of git://repo.or.cz/git/jrn: (32 commits)
  vcs-svn: reset first_commit_done in fast_export_init
  vcs-svn: do not initialize report_buffer twice
  vcs-svn: avoid hangs from corrupt deltas
  vcs-svn: guard against overflow when computing preimage length
  vcs-svn: cap number of bytes read from sliding view
  test-svn-fe: split off "test-svn-fe -d" into a separate function
  vcs-svn: implement text-delta handling
  vcs-svn: let deltas use data from preimage
  vcs-svn: let deltas use data from postimage
  vcs-svn: verify that deltas consume all inline data
  vcs-svn: implement copyfrom_data delta instruction
  vcs-svn: read instructions from deltas
  vcs-svn: read inline data from deltas
  vcs-svn: read the preimage when applying deltas
  vcs-svn: parse svndiff0 window header
  vcs-svn: skeleton of an svn delta parser
  vcs-svn: make buffer_read_binary API more convenient
  vcs-svn: learn to maintain a sliding view of a file
  Makefile: list one vcs-svn/xdiff object or header per line
  vcs-svn: avoid using ls command twice
  ...

Conflicts:
	Makefile
	contrib/svn-fe/svn-fe.txt
2012-01-27 11:20:00 -08:00
Ævar Arnfjörð Bjarmason
952fba9c63 Fix a bitwise negation assignment issue spotted by Sun Studio
Change direct and indirect assignments of the bitwise negation of 0 to
uint32_t variables to have a "U" suffix. I.e. ~0U instead of ~0. This
eliminates warnings under Sun Studio 12 Update 1:

    "vcs-svn/string_pool.c", line 11: warning: initializer will be sign-extended: -1 (E_INIT_SIGN_EXTEND)
    "vcs-svn/string_pool.c", line 81: warning: initializer will be sign-extended: -1 (E_INIT_SIGN_EXTEND)
    "vcs-svn/repo_tree.c", line 112: warning: initializer will be sign-extended: -1 (E_INIT_SIGN_EXTEND)
    "vcs-svn/repo_tree.c", line 112: warning: initializer will be sign-extended: -1 (E_INIT_SIGN_EXTEND)
    "test-treap.c", line 34: warning: initializer will be sign-extended: -1 (E_INIT_SIGN_EXTEND)

The semantics are still the same as demonstrated by this program:

    $ cat test.c && make test && ./test
    #include <stdio.h>
    #include <stdint.h>

    int main(void)
    {
        uint32_t foo = ~0;
        uint32_t bar = ~0U;

        printf("foo = <%u> bar = <%u>\n", foo, bar);

        return 0;
    }
    cc     test.c   -o test
    "test.c", line 5: warning: initializer will be sign-extended: -1
    foo = <4294967295> bar = <4294967295>

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-12-21 10:19:40 -08:00
Dmitry Ivankov
c5bcbcdcfa vcs-svn: reset first_commit_done in fast_export_init
first_commit_done has zero as a default value, but it
is not reset back to zero in fast_export_init.

Reset it back to zero so that each export will have
proper initial state.

Signed-off-by: Dmitry Ivankov <divanorama@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-06-23 10:04:36 -05:00
Dmitry Ivankov
c5f1fbe7bc vcs-svn: do not initialize report_buffer twice
When importing from a dump with deltas, first fast_export_init calls
buffer_fdinit, and then init_report_buffer calls fdopen once again
when processing the first delta.  The second initialization is
redundant and leaks a FILE *.

Remove the redundant on-demand initialization to fix this.
Initializing directly in fast_export_init is simpler and lets the
caller pass an int specifying which fd to use instead of hard-coding
REPORT_FILENO.

Signed-off-by: Dmitry Ivankov <divanorama@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-06-21 05:02:57 -05:00
Jonathan Nieder
3ac10b2e3f vcs-svn: avoid hangs from corrupt deltas
A corrupt Subversion-format delta can request reads past the end of
the preimage.  Set sliding_view::max_off so such corruption is caught
when it appears rather than blocking in an impossible-to-fulfill
read() when input is coming from a socket or pipe.

Inspired-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-06-15 02:32:50 -05:00
Jonathan Nieder
abe27c0cbd vcs-svn: guard against overflow when computing preimage length
Signed integer overflow produces undefined behavior in C and off_t is
a signed type.  For predictable behavior, add some checks to protect
in advance against overflow.

On 32-bit systems ftell as called by buffer_tmpfile_prepare_to_read
is likely to fail with EOVERFLOW when reading the corresponding
postimage, and this patch does not fix that.  So it's more of a
futureproofing measure than a complete fix.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-06-15 02:32:50 -05:00
Jonathan Nieder
157415a9a9 Merge branch 'db/delta-applier' into db/text-delta
* db/delta-applier:
  vcs-svn: cap number of bytes read from sliding view
  test-svn-fe: split off "test-svn-fe -d" into a separate function
2011-06-15 02:31:35 -05:00
Jonathan Nieder
fbdd4f6fb4 vcs-svn: cap number of bytes read from sliding view
Introduce a "max_off" field in struct sliding_view, roughly
representing a maximum number of bytes that can be read from "file".
If it is set to a nonnegative integer, a call to move_window()
attempting to put the right endpoint beyond that offset will return
an error instead.

The idea is to use this when applying Subversion-format deltas to
prevent reads past the end of the preimage (which has known length).
Without such a check, corrupt deltas would cause svn-fe to block
indefinitely when data in the input pipe is exhausted.

Inspired-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-06-15 02:15:22 -05:00
David Barr
7a75e661c5 vcs-svn: implement text-delta handling
Handle input in Subversion's dumpfile format, version 3.  This is the
format produced by "svnrdump dump" and "svnadmin dump --deltas", and
the main difference between v3 dumpfiles and the dumpfiles already
handled is that these can include nodes whose properties and text are
expressed relative to some other node.

To handle such nodes, we find which node the text and properties are
based on, handle its property changes, use the cat-blob command to
request the basis blob from the fast-import backend, use the
svndiff0_apply() helper to apply the text delta on the fly, writing
output to a temporary file, and then measure that postimage file's
length and write its content to the fast-import stream.

The temporary postimage file is shared between delta-using nodes to
avoid some file system overhead.

The svn-fe interface needs to be more complicated to accomodate the
backward flow of information from the fast-import backend to svn-fe.
The backflow fd is not needed when parsing streams without deltas,
though, so existing scripts using svn-fe on v2 dumps should
continue to work.

NEEDSWORK: generalize interface so caller sets the backflow fd, close
temporary file before exiting

Signed-off-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-05-26 02:28:04 -05:00
Jonathan Nieder
e9f3f8b6f4 Merge branch 'db/delta-applier' into db/text-delta
* db/delta-applier:
  vcs-svn: let deltas use data from preimage
  vcs-svn: let deltas use data from postimage
  vcs-svn: verify that deltas consume all inline data
  vcs-svn: implement copyfrom_data delta instruction
  vcs-svn: read instructions from deltas
  vcs-svn: read inline data from deltas
  vcs-svn: read the preimage when applying deltas
  vcs-svn: parse svndiff0 window header
  vcs-svn: skeleton of an svn delta parser
  vcs-svn: make buffer_read_binary API more convenient
  vcs-svn: learn to maintain a sliding view of a file
  Makefile: list one vcs-svn/xdiff object or header per line

Conflicts:
	Makefile
	vcs-svn/LICENSE
2011-05-26 02:27:48 -05:00
Jonathan Nieder
c19d653c4f Merge branch 'db/svn-fe-code-purge' into svn-fe
* db/svn-fe-code-purge:
  vcs-svn: drop obj_pool
  vcs-svn: drop treap
  vcs-svn: drop string_pool
  vcs-svn: pass paths through to fast-import

Conflicts:
	vcs-svn/fast_export.c
	vcs-svn/fast_export.h
	vcs-svn/repo_tree.c
	vcs-svn/repo_tree.h
	vcs-svn/string_pool.c
	vcs-svn/svndump.c
	vcs-svn/trp.txt
2011-05-26 02:12:14 -05:00
Jonathan Nieder
9ecfa8ae4c Merge branch 'db/vcs-svn-incremental' into svn-fe
This teaches svn-fe to incrementally import into an existing
repository (at last!) at the expense of less convenient UI.  Think of
it as growing pains.  This opens the door to many excellent things,
and it would be a bad idea to discourage people from building on it
for much longer.

* db/vcs-svn-incremental:
  vcs-svn: avoid using ls command twice
  vcs-svn: use mark from previous import for parent commit
  vcs-svn: handle filenames with dq correctly
  vcs-svn: quote paths correctly for ls command
  vcs-svn: eliminate repo_tree structure
  vcs-svn: add a comment before each commit
  vcs-svn: save marks for imported commits
  vcs-svn: use higher mark numbers for blobs
  vcs-svn: set up channel to read fast-import cat-blob response

Conflicts:
	t/t9010-svn-fe.sh
	vcs-svn/fast_export.c
	vcs-svn/fast_export.h
	vcs-svn/repo_tree.c
	vcs-svn/svndump.c
2011-05-26 02:02:44 -05:00
Junio C Hamano
793066e790 Merge branch 'rj/sparse'
* rj/sparse:
  sparse: Fix some "symbol not declared" warnings
  sparse: Fix errors due to missing target-specific variables
  sparse: Fix an "symbol 'merge_file' not decared" warning
  sparse: Fix an "symbol 'format_subject' not declared" warning
  sparse: Fix some "Using plain integer as NULL pointer" warnings
  sparse: Fix an "symbol 'cmd_index_pack' not declared" warning
  Makefile: Use cgcc rather than sparse in the check target
2011-04-27 11:36:42 -07:00
Ramsay Jones
c51477229e sparse: Fix some "symbol not declared" warnings
In particular, sparse issues the "symbol 'a_symbol' was not declared.
Should it be static?" warnings for the following symbols:

    attr.c:468:12: 'git_etc_gitattributes'
    attr.c:476:5:  'git_attr_system'
    vcs-svn/svndump.c:282:6: 'svndump_read'
    vcs-svn/svndump.c:417:5: 'svndump_init'
    vcs-svn/svndump.c:432:6: 'svndump_deinit'
    vcs-svn/svndump.c:445:6: 'svndump_reset'

The symbols in attr.c only require file scope, so we add the static
modifier to their declaration.

The symbols in vcs-svn/svndump.c are external symbols, and they
already have extern declarations in the "svndump.h" header file,
so we simply include the header in svndump.c.

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-04-22 10:04:27 -07:00
Jim Meyering
0353a0c4ec remove doubled words, e.g., s/to to/to/, and fix related typos
I found that some doubled words had snuck back into projects from which
I'd already removed them, so now there's a "syntax-check" makefile rule in
gnulib to help prevent recurrence.

Running the command below spotted a few in git, too:

  git ls-files | xargs perl -0777 -n \
    -e 'while (/\b(then?|[iao]n|i[fst]|but|f?or|at|and|[dt])\s+\1\b/gims)' \
    -e '{$n=($` =~ tr/\n/\n/ + 1); ($v=$&)=~s/\n/\\n/g;' \
    -e 'print "$ARGV:$n:$v\n"}'

Signed-off-by: Jim Meyering <meyering@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-04-13 11:59:11 -07:00
Junio C Hamano
44a9cedb00 Merge branch 'svn-fe' of git://repo.or.cz/git/jrn
* 'svn-fe' of git://repo.or.cz/git/jrn:
  tests: kill backgrounded processes more robustly
  vcs-svn: a void function shouldn't try to return something
  tests: make sure input to sed is newline terminated
  vcs-svn: add missing cast to printf argument
2011-03-30 10:49:13 -07:00
Michael Witten
9e113988d3 vcs-svn: a void function shouldn't try to return something
As v1.7.4-rc0~184 (2010-10-04) and C99 §6.8.6.4.1 remind us, standard
C does not permit returning an expression of type void, even for a
tail call.

Noticed with gcc -pedantic:

 vcs-svn/svndump.c: In function 'handle_node':
 vcs-svn/svndump.c:213:3: warning: ISO C forbids 'return' with expression,
  in function returning void [-pedantic]

[jn: with simplified log message]

Signed-off-by: Michael Witten <mfwitten@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-03-29 14:47:02 -05:00
Jonathan Nieder
8cc299daf2 vcs-svn: add missing cast to printf argument
gcc -m32 correctly warns:

 vcs-svn/fast_export.c: In function 'fast_export_commit':
 vcs-svn/fast_export.c:54:2: warning: format '%llu' expects
   argument of type 'long long unsigned int', but argument 2
   has type 'unsigned int' [-Wformat]

Fix it.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-03-28 09:46:44 -07:00
Jonathan Nieder
c846e41078 vcs-svn: let deltas use data from preimage
The copyfrom_source instruction appends data from the preimage buffer
to the end of output.  Its arguments are a length and an offset
relative to the beginning of the source view.

With this change, the delta applier is able to reproduce all 5,636,613
blobs in the early history of the ASF repository.  Tested with

	mkfifo backflow
	svn-fe <svn-asf-public-r0:940166 3<backflow |
	git fast-import --cat-blob-fd=3 3>backflow

with svn-asf-public-r0:940166 produced by whatever version of
Subversion the dumps in /dump/ on svn.apache.org use (presumably
1.6.something).

Improved-by: Ramkumar Ramachandra <artagnon@gmail.com>
Improved-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Ramkumar Ramachandra <artagnon@gmail.com>
2011-03-28 00:33:48 -05:00
Jonathan Nieder
d3f131b57e vcs-svn: let deltas use data from postimage
The copyfrom_target instruction copies appends data that is already
present in the current output view to the end of output.  (The offset
argument is relative to the beginning of output produced in the
current window.)

The region copied is allowed to run past the end of the existing
output.  To support that case, copy one character at a time rather
than calling memcpy or memmove.  This allows copyfrom_target to be
used once to repeat a string many times.  For example:

	COPYFROM_DATA 2
	COPYFROM_OUTPUT 10, 0
	DATA "ab"

would produce the output "ababababababababababab".

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Ramkumar Ramachandra <artagnon@gmail.com>
2011-03-27 23:28:27 -05:00
Jonathan Nieder
4c9b93ed76 vcs-svn: verify that deltas consume all inline data
By constraining the format of deltas, we can more easily detect
corruption and other breakage.

Requiring deltas not to provide unconsumed data also opens the
possibility of ignoring the declared amount of novel data and simply
streaming the data as needed to fulfill copyfrom_data requests.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Ramkumar Ramachandra <artagnon@gmail.com>
2011-03-27 23:28:02 -05:00
Jonathan Nieder
ec71aa2e1f vcs-svn: implement copyfrom_data delta instruction
The copyfrom_data instruction copies a few bytes verbatim from the
novel text section of a window to the postimage.

[jn: with memory leak fix from David]

Improved-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Ramkumar Ramachandra <artagnon@gmail.com>
2011-03-27 23:27:55 -05:00
Jonathan Nieder
ef2ac77e9f vcs-svn: read instructions from deltas
Buffer the instruction section upon encountering it for later
interpretation.

An alternative design would involve parsing the instructions
at this point and buffering them in some processed form.  Using
the unprocessed form is simpler.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Ramkumar Ramachandra <artagnon@gmail.com>
2011-03-27 23:02:05 -05:00
Jonathan Nieder
fc4ae43b2c vcs-svn: read inline data from deltas
Each window of an svndiff0-format delta includes a section for novel
text to be copied to the postimage (in the order it appears in the
window, possibly interspersed with other data).

Slurp in this data when encountering it.  It is not actually necessary
to do so --- it would be just as easy to copy from delta to output
as part of interpreting the relevant instructions --- but this way,
the code that interprets svndiff0 instructions can proceed very
quickly because it does not require I/O.

Subversion's svndiff0 parser rejects deltas that do not consume all
the novel text that was provided.  Omit that check for now so we can
test the new functionality right away, rather than waiting to learn
instructions that consume data.

Do check for truncated data sections.  Subversion's parser rejects
deltas that end in the middle of a declared novel-text section, so it
should be safe for us to reject them, too.

Improved-by: Ramkumar Ramachandra <artagnon@gmail.com>
Improved-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Ramkumar Ramachandra <artagnon@gmail.com>
2011-03-27 22:51:00 -05:00
Jonathan Nieder
bcd254621f vcs-svn: read the preimage when applying deltas
The source view offset heading each svndiff0 window represents a
number of bytes past the beginning of the preimage.  Together with the
source view length, it dictates to the delta applier what portion of
the preimage instructions will refer to.  Read that portion right away
using the sliding window code.

Maybe some day we will use mmap to read data more lazily.

Subversion's implementation tolerates source view offsets pointing
past the end of the preimage file but we do not, for simplicity.

This does not teach the delta applier to read instructions or copy
data from the source view.  Deltas that could produce nonempty output
will still be rejected.

Improved-by: Ramkumar Ramachandra <artagnon@gmail.com>
Improved-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Ramkumar Ramachandra <artagnon@gmail.com>
2011-03-27 22:50:01 -05:00
Jonathan Nieder
252712111f vcs-svn: parse svndiff0 window header
Each window in a subversion delta (svndiff0-format file) starts with a
window header, consisting of five integers with variable-length
representation:

	source view offset
	source view length
	output length
	instructions length
	auxiliary data length

Parse it.  The result is not usable for deltas with nonempty postimage
yet; in fact, this only adds support for deltas without any
instructions or auxiliary data.  This is a good place to stop, though,
since that little support lets us add some simple passing tests
concerning error handling to the test suite.

Improved-by: Ramkumar Ramachandra <artagnon@gmail.com>
Improved-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-03-27 22:42:53 -05:00
Jonathan Nieder
ddcc8c5b46 vcs-svn: skeleton of an svn delta parser
A delta in the subversion delta (svndiff0) format consists of the
magic bytes SVN\0 followed by a sequence of windows of a certain well
specified format (starting with five integers).

Add an svndiff0_apply function and test-svn-fe -d commandline tool to
parse such a delta in the special case of not including any windows.

Later patches will add features to turn this into a fully functional
delta applier for svn-fe to use to parse the streams produced by
"svnrdump dump" and "svnadmin dump --deltas".

The content of symlinks starts with the word "link " in Subversion's
worldview, so we need to be able to prepend that text to input for the
sake of delta application.  So initialization of the input state of
the delta preimage is left to the calling program, giving callers a
chance to seed the buffer with text of their choice.

Improved-by: Ramkumar Ramachandra <artagnon@gmail.com>
Improved-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-03-27 22:41:38 -05:00
Jonathan Nieder
896e4bfcec vcs-svn: make buffer_read_binary API more convenient
buffer_read_binary is a thin wrapper around fread, but its signature
is wrong:

 - fread can fill an arbitrary in-memory buffer.  buffer_read_binary
   is limited to buffers whose size is representable by a 32-bit
   integer.
 - The result from fread is the number of bytes actually read.
   buffer_read_binary only reports the number of bytes read by
   incrementing sb->len by that amount and returns void.

Fix both: let buffer_read_binary accept a size_t instead of uint32_t
for the number of bytes to read and as a convenience return the number
of bytes actually read.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-03-27 22:37:05 -05:00
Jonathan Nieder
9d2f5ddfe5 vcs-svn: learn to maintain a sliding view of a file
Each section of a Subversion-format delta only requires examining (and
keeping in random-access memory) a small portion of the preimage.  At
any moment, this portion starts at a certain file offset and has a
well-defined length, and as the delta is applied, the portion advances
from the beginning to the end of the preimage.  Add a move_window
function to keep track of this view into the preimage.

You can use it like this:

	buffer_init(f, NULL);
	struct sliding_view window = SLIDING_VIEW_INIT(f);
	move_window(&window, 3, 7);	/* (1) */
	move_window(&window, 5, 5);	/* (2) */
	move_window(&window, 12, 2);	/* (3) */
	strbuf_release(&window.buf);
	buffer_deinit(f);

The data structure is called sliding_view instead of _window to
prevent confusion with svndiff0 Windows.

In this example, (1) reads 10 bytes and discards the first 3;
(2) discards the first 2, which are not needed any more; and (3) skips
2 bytes and reads 2 new bytes to work with.

When move_window returns, the file position indicator is at position
window->off + window->width and the data from positions window->off to
the current file position are stored in window->buf.

This function performs only sequential access from the input file and
never seeks, so it can be safely used on pipes and sockets.

On end-of-file, move_window silently reads less than the caller
requested.  On other errors, it prints a message and returns -1.

Helped-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-03-27 20:23:32 -05:00
Jonathan Nieder
41e6b91f01 vcs-svn: add missing cast to printf argument
gcc -m32 correctly warns:

 vcs-svn/fast_export.c: In function 'fast_export_commit':
 vcs-svn/fast_export.c:54:2: warning: format '%llu' expects
   argument of type 'long long unsigned int', but argument 2
   has type 'unsigned int' [-Wformat]

Fix it.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-03-27 12:21:12 -05:00
Junio C Hamano
a080fdd1b1 Merge branch 'svn-fe' of git://repo.or.cz/git/jrn
* 'svn-fe' of git://repo.or.cz/git/jrn:
  vcs-svn: handle log message with embedded NUL
  vcs-svn: avoid unnecessary copying of log message and author
  vcs-svn: remove buffer_read_string
  vcs-svn: make reading of properties binary-safe
2011-03-26 11:35:41 -07:00
David Barr
43155cfe14 vcs-svn: avoid using ls command twice
Currently there are two functions to retrieve the mode and content
at a path:

	const char *repo_read_path(const uint32_t *path);
	uint32_t repo_read_mode(const uint32_t *path)

Replace them with a single function with two return values.  This
means we can use one round-trip to get the same information from
fast-import that previously took two.

Signed-off-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
2011-03-26 01:00:05 -05:00