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authorJunio C Hamano <gitster@pobox.com>2011-08-18 00:36:06 (GMT)
committerJunio C Hamano <gitster@pobox.com>2011-08-18 00:36:06 (GMT)
commitca01600306863ecfa8bbef769b8e1386cb149785 (patch)
tree30507da396d4a19240aed15c47a2f4356dd3987d
parent2f5cb6aa1e2eb7b12df85d5ddc4d8bc79be47b3d (diff)
parent6486a84cb8e69ddf03b2139db3d968400e05f5b3 (diff)
downloadgit-ca01600306863ecfa8bbef769b8e1386cb149785.zip
git-ca01600306863ecfa8bbef769b8e1386cb149785.tar.gz
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Merge branch 'rc/histogram-diff'
* rc/histogram-diff: xdiff/xhistogram: drop need for additional variable xdiff/xhistogram: rely on xdl_trim_ends() xdiff/xhistogram: rework handling of recursed results xdiff: do away with xdl_mmfile_next() Make test number unique xdiff/xprepare: use a smaller sample size for histogram diff xdiff/xprepare: skip classification teach --histogram to diff t4033-diff-patience: factor out tests xdiff/xpatience: factor out fall-back-diff function xdiff/xprepare: refactor abort cleanups xdiff/xprepare: use memset()
-rw-r--r--Makefile2
-rw-r--r--diff.c2
-rw-r--r--merge-recursive.c2
-rw-r--r--t/lib-diff-alternative.sh165
-rwxr-xr-xt/t4033-diff-patience.sh162
-rwxr-xr-xt/t4050-diff-histogram.sh12
-rw-r--r--xdiff/xdiff.h2
-rw-r--r--xdiff/xdiffi.c3
-rw-r--r--xdiff/xdiffi.h2
-rw-r--r--xdiff/xhistogram.c363
-rw-r--r--xdiff/xpatience.c27
-rw-r--r--xdiff/xprepare.c143
-rw-r--r--xdiff/xutils.c51
-rw-r--r--xdiff/xutils.h4
14 files changed, 655 insertions, 285 deletions
diff --git a/Makefile b/Makefile
index 8dd782f..89cc624 100644
--- a/Makefile
+++ b/Makefile
@@ -1876,7 +1876,7 @@ ifndef NO_CURL
GIT_OBJS += http.o http-walker.o remote-curl.o
endif
XDIFF_OBJS = xdiff/xdiffi.o xdiff/xprepare.o xdiff/xutils.o xdiff/xemit.o \
- xdiff/xmerge.o xdiff/xpatience.o
+ xdiff/xmerge.o xdiff/xpatience.o xdiff/xhistogram.o
VCSSVN_OBJS = vcs-svn/string_pool.o vcs-svn/line_buffer.o \
vcs-svn/repo_tree.o vcs-svn/fast_export.o vcs-svn/svndump.o
VCSSVN_TEST_OBJS = test-obj-pool.o test-string-pool.o \
diff --git a/diff.c b/diff.c
index 93ef9a2..d3d8dae 100644
--- a/diff.c
+++ b/diff.c
@@ -3393,6 +3393,8 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
else if (!strcmp(arg, "--patience"))
DIFF_XDL_SET(options, PATIENCE_DIFF);
+ else if (!strcmp(arg, "--histogram"))
+ DIFF_XDL_SET(options, HISTOGRAM_DIFF);
/* flags options */
else if (!strcmp(arg, "--binary")) {
diff --git a/merge-recursive.c b/merge-recursive.c
index db9ba19..0cc1e6f 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -1759,6 +1759,8 @@ int parse_merge_opt(struct merge_options *o, const char *s)
o->subtree_shift = s + strlen("subtree=");
else if (!strcmp(s, "patience"))
o->xdl_opts |= XDF_PATIENCE_DIFF;
+ else if (!strcmp(s, "histogram"))
+ o->xdl_opts |= XDF_HISTOGRAM_DIFF;
else if (!strcmp(s, "ignore-space-change"))
o->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
else if (!strcmp(s, "ignore-all-space"))
diff --git a/t/lib-diff-alternative.sh b/t/lib-diff-alternative.sh
new file mode 100644
index 0000000..75ffd91
--- /dev/null
+++ b/t/lib-diff-alternative.sh
@@ -0,0 +1,165 @@
+#!/bin/sh
+
+test_diff_frobnitz() {
+ cat >file1 <<\EOF
+#include <stdio.h>
+
+// Frobs foo heartily
+int frobnitz(int foo)
+{
+ int i;
+ for(i = 0; i < 10; i++)
+ {
+ printf("Your answer is: ");
+ printf("%d\n", foo);
+ }
+}
+
+int fact(int n)
+{
+ if(n > 1)
+ {
+ return fact(n-1) * n;
+ }
+ return 1;
+}
+
+int main(int argc, char **argv)
+{
+ frobnitz(fact(10));
+}
+EOF
+
+ cat >file2 <<\EOF
+#include <stdio.h>
+
+int fib(int n)
+{
+ if(n > 2)
+ {
+ return fib(n-1) + fib(n-2);
+ }
+ return 1;
+}
+
+// Frobs foo heartily
+int frobnitz(int foo)
+{
+ int i;
+ for(i = 0; i < 10; i++)
+ {
+ printf("%d\n", foo);
+ }
+}
+
+int main(int argc, char **argv)
+{
+ frobnitz(fib(10));
+}
+EOF
+
+ cat >expect <<\EOF
+diff --git a/file1 b/file2
+index 6faa5a3..e3af329 100644
+--- a/file1
++++ b/file2
+@@ -1,26 +1,25 @@
+ #include <stdio.h>
+
++int fib(int n)
++{
++ if(n > 2)
++ {
++ return fib(n-1) + fib(n-2);
++ }
++ return 1;
++}
++
+ // Frobs foo heartily
+ int frobnitz(int foo)
+ {
+ int i;
+ for(i = 0; i < 10; i++)
+ {
+- printf("Your answer is: ");
+ printf("%d\n", foo);
+ }
+ }
+
+-int fact(int n)
+-{
+- if(n > 1)
+- {
+- return fact(n-1) * n;
+- }
+- return 1;
+-}
+-
+ int main(int argc, char **argv)
+ {
+- frobnitz(fact(10));
++ frobnitz(fib(10));
+ }
+EOF
+
+ STRATEGY=$1
+
+ test_expect_success "$STRATEGY diff" '
+ test_must_fail git diff --no-index "--$STRATEGY" file1 file2 > output &&
+ test_cmp expect output
+ '
+
+ test_expect_success "$STRATEGY diff output is valid" '
+ mv file2 expect &&
+ git apply < output &&
+ test_cmp expect file2
+ '
+}
+
+test_diff_unique() {
+ cat >uniq1 <<\EOF
+1
+2
+3
+4
+5
+6
+EOF
+
+ cat >uniq2 <<\EOF
+a
+b
+c
+d
+e
+f
+EOF
+
+ cat >expect <<\EOF
+diff --git a/uniq1 b/uniq2
+index b414108..0fdf397 100644
+--- a/uniq1
++++ b/uniq2
+@@ -1,6 +1,6 @@
+-1
+-2
+-3
+-4
+-5
+-6
++a
++b
++c
++d
++e
++f
+EOF
+
+ STRATEGY=$1
+
+ test_expect_success 'completely different files' '
+ test_must_fail git diff --no-index "--$STRATEGY" uniq1 uniq2 > output &&
+ test_cmp expect output
+ '
+}
+
diff --git a/t/t4033-diff-patience.sh b/t/t4033-diff-patience.sh
index 1eb1498..3c9932e 100755
--- a/t/t4033-diff-patience.sh
+++ b/t/t4033-diff-patience.sh
@@ -3,166 +3,10 @@
test_description='patience diff algorithm'
. ./test-lib.sh
+. "$TEST_DIRECTORY"/lib-diff-alternative.sh
-cat >file1 <<\EOF
-#include <stdio.h>
+test_diff_frobnitz "patience"
-// Frobs foo heartily
-int frobnitz(int foo)
-{
- int i;
- for(i = 0; i < 10; i++)
- {
- printf("Your answer is: ");
- printf("%d\n", foo);
- }
-}
-
-int fact(int n)
-{
- if(n > 1)
- {
- return fact(n-1) * n;
- }
- return 1;
-}
-
-int main(int argc, char **argv)
-{
- frobnitz(fact(10));
-}
-EOF
-
-cat >file2 <<\EOF
-#include <stdio.h>
-
-int fib(int n)
-{
- if(n > 2)
- {
- return fib(n-1) + fib(n-2);
- }
- return 1;
-}
-
-// Frobs foo heartily
-int frobnitz(int foo)
-{
- int i;
- for(i = 0; i < 10; i++)
- {
- printf("%d\n", foo);
- }
-}
-
-int main(int argc, char **argv)
-{
- frobnitz(fib(10));
-}
-EOF
-
-cat >expect <<\EOF
-diff --git a/file1 b/file2
-index 6faa5a3..e3af329 100644
---- a/file1
-+++ b/file2
-@@ -1,26 +1,25 @@
- #include <stdio.h>
-
-+int fib(int n)
-+{
-+ if(n > 2)
-+ {
-+ return fib(n-1) + fib(n-2);
-+ }
-+ return 1;
-+}
-+
- // Frobs foo heartily
- int frobnitz(int foo)
- {
- int i;
- for(i = 0; i < 10; i++)
- {
-- printf("Your answer is: ");
- printf("%d\n", foo);
- }
- }
-
--int fact(int n)
--{
-- if(n > 1)
-- {
-- return fact(n-1) * n;
-- }
-- return 1;
--}
--
- int main(int argc, char **argv)
- {
-- frobnitz(fact(10));
-+ frobnitz(fib(10));
- }
-EOF
-
-test_expect_success 'patience diff' '
-
- test_must_fail git diff --no-index --patience file1 file2 > output &&
- test_cmp expect output
-
-'
-
-test_expect_success 'patience diff output is valid' '
-
- mv file2 expect &&
- git apply < output &&
- test_cmp expect file2
-
-'
-
-cat >uniq1 <<\EOF
-1
-2
-3
-4
-5
-6
-EOF
-
-cat >uniq2 <<\EOF
-a
-b
-c
-d
-e
-f
-EOF
-
-cat >expect <<\EOF
-diff --git a/uniq1 b/uniq2
-index b414108..0fdf397 100644
---- a/uniq1
-+++ b/uniq2
-@@ -1,6 +1,6 @@
--1
--2
--3
--4
--5
--6
-+a
-+b
-+c
-+d
-+e
-+f
-EOF
-
-test_expect_success 'completely different files' '
-
- test_must_fail git diff --no-index --patience uniq1 uniq2 > output &&
- test_cmp expect output
-
-'
+test_diff_unique "patience"
test_done
diff --git a/t/t4050-diff-histogram.sh b/t/t4050-diff-histogram.sh
new file mode 100755
index 0000000..fd3e86a
--- /dev/null
+++ b/t/t4050-diff-histogram.sh
@@ -0,0 +1,12 @@
+#!/bin/sh
+
+test_description='histogram diff algorithm'
+
+. ./test-lib.sh
+. "$TEST_DIRECTORY"/lib-diff-alternative.sh
+
+test_diff_frobnitz "histogram"
+
+test_diff_unique "histogram"
+
+test_done
diff --git a/xdiff/xdiff.h b/xdiff/xdiff.h
index 711048e..4beb10c 100644
--- a/xdiff/xdiff.h
+++ b/xdiff/xdiff.h
@@ -33,6 +33,7 @@ extern "C" {
#define XDF_IGNORE_WHITESPACE_CHANGE (1 << 3)
#define XDF_IGNORE_WHITESPACE_AT_EOL (1 << 4)
#define XDF_PATIENCE_DIFF (1 << 5)
+#define XDF_HISTOGRAM_DIFF (1 << 6)
#define XDF_WHITESPACE_FLAGS (XDF_IGNORE_WHITESPACE | XDF_IGNORE_WHITESPACE_CHANGE | XDF_IGNORE_WHITESPACE_AT_EOL)
#define XDL_PATCH_NORMAL '-'
@@ -105,7 +106,6 @@ typedef struct s_bdiffparam {
#define xdl_realloc(ptr,x) realloc(ptr,x)
void *xdl_mmfile_first(mmfile_t *mmf, long *size);
-void *xdl_mmfile_next(mmfile_t *mmf, long *size);
long xdl_mmfile_size(mmfile_t *mmf);
int xdl_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp,
diff --git a/xdiff/xdiffi.c b/xdiff/xdiffi.c
index da67c04..75a3922 100644
--- a/xdiff/xdiffi.c
+++ b/xdiff/xdiffi.c
@@ -331,6 +331,9 @@ int xdl_do_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp,
if (xpp->flags & XDF_PATIENCE_DIFF)
return xdl_do_patience_diff(mf1, mf2, xpp, xe);
+ if (xpp->flags & XDF_HISTOGRAM_DIFF)
+ return xdl_do_histogram_diff(mf1, mf2, xpp, xe);
+
if (xdl_prepare_env(mf1, mf2, xpp, xe) < 0) {
return -1;
diff --git a/xdiff/xdiffi.h b/xdiff/xdiffi.h
index ad033a8..7a92ea9 100644
--- a/xdiff/xdiffi.h
+++ b/xdiff/xdiffi.h
@@ -57,5 +57,7 @@ int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
xdemitconf_t const *xecfg);
int xdl_do_patience_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp,
xdfenv_t *env);
+int xdl_do_histogram_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp,
+ xdfenv_t *env);
#endif /* #if !defined(XDIFFI_H) */
diff --git a/xdiff/xhistogram.c b/xdiff/xhistogram.c
new file mode 100644
index 0000000..18f6f99
--- /dev/null
+++ b/xdiff/xhistogram.c
@@ -0,0 +1,363 @@
+/*
+ * Copyright (C) 2010, Google Inc.
+ * and other copyright owners as documented in JGit's IP log.
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials provided
+ * with the distribution.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. nor the
+ * names of its contributors may be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "xinclude.h"
+#include "xtypes.h"
+#include "xdiff.h"
+
+#define MAX_PTR UINT_MAX
+#define MAX_CNT UINT_MAX
+
+#define LINE_END(n) (line##n + count##n - 1)
+#define LINE_END_PTR(n) (*line##n + *count##n - 1)
+
+struct histindex {
+ struct record {
+ unsigned int ptr, cnt;
+ struct record *next;
+ } **records, /* an ocurrence */
+ **line_map; /* map of line to record chain */
+ chastore_t rcha;
+ unsigned int *next_ptrs;
+ unsigned int table_bits,
+ records_size,
+ line_map_size;
+
+ unsigned int max_chain_length,
+ key_shift,
+ ptr_shift;
+
+ unsigned int cnt,
+ has_common;
+
+ xdfenv_t *env;
+ xpparam_t const *xpp;
+};
+
+struct region {
+ unsigned int begin1, end1;
+ unsigned int begin2, end2;
+};
+
+#define LINE_MAP(i, a) (i->line_map[(a) - i->ptr_shift])
+
+#define NEXT_PTR(index, ptr) \
+ (index->next_ptrs[(ptr) - index->ptr_shift])
+
+#define CNT(index, ptr) \
+ ((LINE_MAP(index, ptr))->cnt)
+
+#define REC(env, s, l) \
+ (env->xdf##s.recs[l - 1])
+
+static int cmp_recs(xpparam_t const *xpp,
+ xrecord_t *r1, xrecord_t *r2)
+{
+ return r1->ha == r2->ha &&
+ xdl_recmatch(r1->ptr, r1->size, r2->ptr, r2->size,
+ xpp->flags);
+}
+
+#define CMP_ENV(xpp, env, s1, l1, s2, l2) \
+ (cmp_recs(xpp, REC(env, s1, l1), REC(env, s2, l2)))
+
+#define CMP(i, s1, l1, s2, l2) \
+ (cmp_recs(i->xpp, REC(i->env, s1, l1), REC(i->env, s2, l2)))
+
+#define TABLE_HASH(index, side, line) \
+ XDL_HASHLONG((REC(index->env, side, line))->ha, index->table_bits)
+
+static int scanA(struct histindex *index, int line1, int count1)
+{
+ unsigned int ptr, tbl_idx;
+ unsigned int chain_len;
+ struct record **rec_chain, *rec;
+
+ for (ptr = LINE_END(1); line1 <= ptr; ptr--) {
+ tbl_idx = TABLE_HASH(index, 1, ptr);
+ rec_chain = index->records + tbl_idx;
+ rec = *rec_chain;
+
+ chain_len = 0;
+ while (rec) {
+ if (CMP(index, 1, rec->ptr, 1, ptr)) {
+ /*
+ * ptr is identical to another element. Insert
+ * it onto the front of the existing element
+ * chain.
+ */
+ NEXT_PTR(index, ptr) = rec->ptr;
+ rec->ptr = ptr;
+ /* cap rec->cnt at MAX_CNT */
+ rec->cnt = XDL_MIN(MAX_CNT, rec->cnt + 1);
+ LINE_MAP(index, ptr) = rec;
+ goto continue_scan;
+ }
+
+ rec = rec->next;
+ chain_len++;
+ }
+
+ if (chain_len == index->max_chain_length)
+ return -1;
+
+ /*
+ * This is the first time we have ever seen this particular
+ * element in the sequence. Construct a new chain for it.
+ */
+ if (!(rec = xdl_cha_alloc(&index->rcha)))
+ return -1;
+ rec->ptr = ptr;
+ rec->cnt = 1;
+ rec->next = *rec_chain;
+ *rec_chain = rec;
+ LINE_MAP(index, ptr) = rec;
+
+continue_scan:
+ ; /* no op */
+ }
+
+ return 0;
+}
+
+static int try_lcs(struct histindex *index, struct region *lcs, int b_ptr,
+ int line1, int count1, int line2, int count2)
+{
+ unsigned int b_next = b_ptr + 1;
+ struct record *rec = index->records[TABLE_HASH(index, 2, b_ptr)];
+ unsigned int as, ae, bs, be, np, rc;
+ int should_break;
+
+ for (; rec; rec = rec->next) {
+ if (rec->cnt > index->cnt) {
+ if (!index->has_common)
+ index->has_common = CMP(index, 1, rec->ptr, 2, b_ptr);
+ continue;
+ }
+
+ as = rec->ptr;
+ if (!CMP(index, 1, as, 2, b_ptr))
+ continue;
+
+ index->has_common = 1;
+ for (;;) {
+ should_break = 0;
+ np = NEXT_PTR(index, as);
+ bs = b_ptr;
+ ae = as;
+ be = bs;
+ rc = rec->cnt;
+
+ while (line1 < as && line2 < bs
+ && CMP(index, 1, as - 1, 2, bs - 1)) {
+ as--;
+ bs--;
+ if (1 < rc)
+ rc = XDL_MIN(rc, CNT(index, as));
+ }
+ while (ae < LINE_END(1) && be < LINE_END(2)
+ && CMP(index, 1, ae + 1, 2, be + 1)) {
+ ae++;
+ be++;
+ if (1 < rc)
+ rc = XDL_MIN(rc, CNT(index, ae));
+ }
+
+ if (b_next <= be)
+ b_next = be + 1;
+ if (lcs->end1 - lcs->begin1 < ae - as || rc < index->cnt) {
+ lcs->begin1 = as;
+ lcs->begin2 = bs;
+ lcs->end1 = ae;
+ lcs->end2 = be;
+ index->cnt = rc;
+ }
+
+ if (np == 0)
+ break;
+
+ while (np <= ae) {
+ np = NEXT_PTR(index, np);
+ if (np == 0) {
+ should_break = 1;
+ break;
+ }
+ }
+
+ if (should_break)
+ break;
+
+ as = np;
+ }
+ }
+ return b_next;
+}
+
+static int find_lcs(struct histindex *index, struct region *lcs,
+ int line1, int count1, int line2, int count2) {
+ int b_ptr;
+
+ if (scanA(index, line1, count1))
+ return -1;
+
+ index->cnt = index->max_chain_length + 1;
+
+ for (b_ptr = line2; b_ptr <= LINE_END(2); )
+ b_ptr = try_lcs(index, lcs, b_ptr, line1, count1, line2, count2);
+
+ return index->has_common && index->max_chain_length < index->cnt;
+}
+
+static int fall_back_to_classic_diff(struct histindex *index,
+ int line1, int count1, int line2, int count2)
+{
+ xpparam_t xpp;
+ xpp.flags = index->xpp->flags & ~XDF_HISTOGRAM_DIFF;
+
+ return xdl_fall_back_diff(index->env, &xpp,
+ line1, count1, line2, count2);
+}
+
+static int histogram_diff(xpparam_t const *xpp, xdfenv_t *env,
+ int line1, int count1, int line2, int count2)
+{
+ struct histindex index;
+ struct region lcs;
+ int sz;
+ int result = -1;
+
+ if (count1 <= 0 && count2 <= 0)
+ return 0;
+
+ if (LINE_END(1) >= MAX_PTR)
+ return -1;
+
+ if (!count1) {
+ while(count2--)
+ env->xdf2.rchg[line2++ - 1] = 1;
+ return 0;
+ } else if (!count2) {
+ while(count1--)
+ env->xdf1.rchg[line1++ - 1] = 1;
+ return 0;
+ }
+
+ memset(&index, 0, sizeof(index));
+
+ index.env = env;
+ index.xpp = xpp;
+
+ index.records = NULL;
+ index.line_map = NULL;
+ /* in case of early xdl_cha_free() */
+ index.rcha.head = NULL;
+
+ index.table_bits = xdl_hashbits(count1);
+ sz = index.records_size = 1 << index.table_bits;
+ sz *= sizeof(struct record *);
+ if (!(index.records = (struct record **) xdl_malloc(sz)))
+ goto cleanup;
+ memset(index.records, 0, sz);
+
+ sz = index.line_map_size = count1;
+ sz *= sizeof(struct record *);
+ if (!(index.line_map = (struct record **) xdl_malloc(sz)))
+ goto cleanup;
+ memset(index.line_map, 0, sz);
+
+ sz = index.line_map_size;
+ sz *= sizeof(unsigned int);
+ if (!(index.next_ptrs = (unsigned int *) xdl_malloc(sz)))
+ goto cleanup;
+ memset(index.next_ptrs, 0, sz);
+
+ /* lines / 4 + 1 comes from xprepare.c:xdl_prepare_ctx() */
+ if (xdl_cha_init(&index.rcha, sizeof(struct record), count1 / 4 + 1) < 0)
+ goto cleanup;
+
+ index.ptr_shift = line1;
+ index.max_chain_length = 64;
+
+ memset(&lcs, 0, sizeof(lcs));
+ if (find_lcs(&index, &lcs, line1, count1, line2, count2))
+ result = fall_back_to_classic_diff(&index, line1, count1, line2, count2);
+ else {
+ if (lcs.begin1 == 0 && lcs.begin2 == 0) {
+ while (count1--)
+ env->xdf1.rchg[line1++ - 1] = 1;
+ while (count2--)
+ env->xdf2.rchg[line2++ - 1] = 1;
+ result = 0;
+ } else {
+ result = histogram_diff(xpp, env,
+ line1, lcs.begin1 - line1,
+ line2, lcs.begin2 - line2);
+ if (result)
+ goto cleanup;
+ result = histogram_diff(xpp, env,
+ lcs.end1 + 1, LINE_END(1) - lcs.end1,
+ lcs.end2 + 1, LINE_END(2) - lcs.end2);
+ if (result)
+ goto cleanup;
+ }
+ }
+
+cleanup:
+ xdl_free(index.records);
+ xdl_free(index.line_map);
+ xdl_free(index.next_ptrs);
+ xdl_cha_free(&index.rcha);
+
+ return result;
+}
+
+int xdl_do_histogram_diff(mmfile_t *file1, mmfile_t *file2,
+ xpparam_t const *xpp, xdfenv_t *env)
+{
+ if (xdl_prepare_env(file1, file2, xpp, env) < 0)
+ return -1;
+
+ return histogram_diff(xpp, env,
+ env->xdf1.dstart + 1, env->xdf1.dend - env->xdf1.dstart + 1,
+ env->xdf2.dstart + 1, env->xdf2.dend - env->xdf2.dstart + 1);
+}
diff --git a/xdiff/xpatience.c b/xdiff/xpatience.c
index e42c16a..fdd7d02 100644
--- a/xdiff/xpatience.c
+++ b/xdiff/xpatience.c
@@ -287,34 +287,11 @@ static int walk_common_sequence(struct hashmap *map, struct entry *first,
static int fall_back_to_classic_diff(struct hashmap *map,
int line1, int count1, int line2, int count2)
{
- /*
- * This probably does not work outside Git, since
- * we have a very simple mmfile structure.
- *
- * Note: ideally, we would reuse the prepared environment, but
- * the libxdiff interface does not (yet) allow for diffing only
- * ranges of lines instead of the whole files.
- */
- mmfile_t subfile1, subfile2;
xpparam_t xpp;
- xdfenv_t env;
-
- subfile1.ptr = (char *)map->env->xdf1.recs[line1 - 1]->ptr;
- subfile1.size = map->env->xdf1.recs[line1 + count1 - 2]->ptr +
- map->env->xdf1.recs[line1 + count1 - 2]->size - subfile1.ptr;
- subfile2.ptr = (char *)map->env->xdf2.recs[line2 - 1]->ptr;
- subfile2.size = map->env->xdf2.recs[line2 + count2 - 2]->ptr +
- map->env->xdf2.recs[line2 + count2 - 2]->size - subfile2.ptr;
xpp.flags = map->xpp->flags & ~XDF_PATIENCE_DIFF;
- if (xdl_do_diff(&subfile1, &subfile2, &xpp, &env) < 0)
- return -1;
- memcpy(map->env->xdf1.rchg + line1 - 1, env.xdf1.rchg, count1);
- memcpy(map->env->xdf2.rchg + line2 - 1, env.xdf2.rchg, count2);
-
- xdl_free_env(&env);
-
- return 0;
+ return xdl_fall_back_diff(map->env, &xpp,
+ line1, count1, line2, count2);
}
/*
diff --git a/xdiff/xprepare.c b/xdiff/xprepare.c
index 1689085..620fc9a 100644
--- a/xdiff/xprepare.c
+++ b/xdiff/xprepare.c
@@ -26,6 +26,8 @@
#define XDL_KPDIS_RUN 4
#define XDL_MAX_EQLIMIT 1024
#define XDL_SIMSCAN_WINDOW 100
+#define XDL_GUESS_NLINES1 256
+#define XDL_GUESS_NLINES2 20
typedef struct s_xdlclass {
@@ -64,8 +66,6 @@ static int xdl_optimize_ctxs(xdfile_t *xdf1, xdfile_t *xdf2);
static int xdl_init_classifier(xdlclassifier_t *cf, long size, long flags) {
- long i;
-
cf->flags = flags;
cf->hbits = xdl_hashbits((unsigned int) size);
@@ -80,8 +80,7 @@ static int xdl_init_classifier(xdlclassifier_t *cf, long size, long flags) {
xdl_cha_free(&cf->ncha);
return -1;
}
- for (i = 0; i < cf->hsize; i++)
- cf->rchash[i] = NULL;
+ memset(cf->rchash, 0, cf->hsize * sizeof(xdlclass_t *));
cf->count = 0;
@@ -136,7 +135,7 @@ static int xdl_classify_record(xdlclassifier_t *cf, xrecord_t **rhash, unsigned
static int xdl_prepare_ctx(mmfile_t *mf, long narec, xpparam_t const *xpp,
xdlclassifier_t *cf, xdfile_t *xdf) {
unsigned int hbits;
- long i, nrec, hsize, bsize;
+ long nrec, hsize, bsize;
unsigned long hav;
char const *blk, *cur, *top, *prev;
xrecord_t *crec;
@@ -146,96 +145,59 @@ static int xdl_prepare_ctx(mmfile_t *mf, long narec, xpparam_t const *xpp,
char *rchg;
long *rindex;
- if (xdl_cha_init(&xdf->rcha, sizeof(xrecord_t), narec / 4 + 1) < 0) {
-
- return -1;
- }
- if (!(recs = (xrecord_t **) xdl_malloc(narec * sizeof(xrecord_t *)))) {
-
- xdl_cha_free(&xdf->rcha);
- return -1;
- }
-
- hbits = xdl_hashbits((unsigned int) narec);
- hsize = 1 << hbits;
- if (!(rhash = (xrecord_t **) xdl_malloc(hsize * sizeof(xrecord_t *)))) {
-
- xdl_free(recs);
- xdl_cha_free(&xdf->rcha);
- return -1;
+ ha = NULL;
+ rindex = NULL;
+ rchg = NULL;
+ rhash = NULL;
+ recs = NULL;
+
+ if (xdl_cha_init(&xdf->rcha, sizeof(xrecord_t), narec / 4 + 1) < 0)
+ goto abort;
+ if (!(recs = (xrecord_t **) xdl_malloc(narec * sizeof(xrecord_t *))))
+ goto abort;
+
+ if (xpp->flags & XDF_HISTOGRAM_DIFF)
+ hbits = hsize = 0;
+ else {
+ hbits = xdl_hashbits((unsigned int) narec);
+ hsize = 1 << hbits;
+ if (!(rhash = (xrecord_t **) xdl_malloc(hsize * sizeof(xrecord_t *))))
+ goto abort;
+ memset(rhash, 0, hsize * sizeof(xrecord_t *));
}
- for (i = 0; i < hsize; i++)
- rhash[i] = NULL;
nrec = 0;
if ((cur = blk = xdl_mmfile_first(mf, &bsize)) != NULL) {
- for (top = blk + bsize;;) {
- if (cur >= top) {
- if (!(cur = blk = xdl_mmfile_next(mf, &bsize)))
- break;
- top = blk + bsize;
- }
+ for (top = blk + bsize; cur < top; ) {
prev = cur;
hav = xdl_hash_record(&cur, top, xpp->flags);
if (nrec >= narec) {
narec *= 2;
- if (!(rrecs = (xrecord_t **) xdl_realloc(recs, narec * sizeof(xrecord_t *)))) {
-
- xdl_free(rhash);
- xdl_free(recs);
- xdl_cha_free(&xdf->rcha);
- return -1;
- }
+ if (!(rrecs = (xrecord_t **) xdl_realloc(recs, narec * sizeof(xrecord_t *))))
+ goto abort;
recs = rrecs;
}
- if (!(crec = xdl_cha_alloc(&xdf->rcha))) {
-
- xdl_free(rhash);
- xdl_free(recs);
- xdl_cha_free(&xdf->rcha);
- return -1;
- }
+ if (!(crec = xdl_cha_alloc(&xdf->rcha)))
+ goto abort;
crec->ptr = prev;
crec->size = (long) (cur - prev);
crec->ha = hav;
recs[nrec++] = crec;
- if (xdl_classify_record(cf, rhash, hbits, crec) < 0) {
-
- xdl_free(rhash);
- xdl_free(recs);
- xdl_cha_free(&xdf->rcha);
- return -1;
- }
+ if (!(xpp->flags & XDF_HISTOGRAM_DIFF) &&
+ xdl_classify_record(cf, rhash, hbits, crec) < 0)
+ goto abort;
}
}
- if (!(rchg = (char *) xdl_malloc((nrec + 2) * sizeof(char)))) {
-
- xdl_free(rhash);
- xdl_free(recs);
- xdl_cha_free(&xdf->rcha);
- return -1;
- }
+ if (!(rchg = (char *) xdl_malloc((nrec + 2) * sizeof(char))))
+ goto abort;
memset(rchg, 0, (nrec + 2) * sizeof(char));
- if (!(rindex = (long *) xdl_malloc((nrec + 1) * sizeof(long)))) {
-
- xdl_free(rchg);
- xdl_free(rhash);
- xdl_free(recs);
- xdl_cha_free(&xdf->rcha);
- return -1;
- }
- if (!(ha = (unsigned long *) xdl_malloc((nrec + 1) * sizeof(unsigned long)))) {
-
- xdl_free(rindex);
- xdl_free(rchg);
- xdl_free(rhash);
- xdl_free(recs);
- xdl_cha_free(&xdf->rcha);
- return -1;
- }
+ if (!(rindex = (long *) xdl_malloc((nrec + 1) * sizeof(long))))
+ goto abort;
+ if (!(ha = (unsigned long *) xdl_malloc((nrec + 1) * sizeof(unsigned long))))
+ goto abort;
xdf->nrec = nrec;
xdf->recs = recs;
@@ -249,6 +211,15 @@ static int xdl_prepare_ctx(mmfile_t *mf, long narec, xpparam_t const *xpp,
xdf->dend = nrec - 1;
return 0;
+
+abort:
+ xdl_free(ha);
+ xdl_free(rindex);
+ xdl_free(rchg);
+ xdl_free(rhash);
+ xdl_free(recs);
+ xdl_cha_free(&xdf->rcha);
+ return -1;
}
@@ -265,13 +236,23 @@ static void xdl_free_ctx(xdfile_t *xdf) {
int xdl_prepare_env(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp,
xdfenv_t *xe) {
- long enl1, enl2;
+ long enl1, enl2, sample;
xdlclassifier_t cf;
- enl1 = xdl_guess_lines(mf1) + 1;
- enl2 = xdl_guess_lines(mf2) + 1;
+ /*
+ * For histogram diff, we can afford a smaller sample size and
+ * thus a poorer estimate of the number of lines, as the hash
+ * table (rhash) won't be filled up/grown. The number of lines
+ * (nrecs) will be updated correctly anyway by
+ * xdl_prepare_ctx().
+ */
+ sample = xpp->flags & XDF_HISTOGRAM_DIFF ? XDL_GUESS_NLINES2 : XDL_GUESS_NLINES1;
+
+ enl1 = xdl_guess_lines(mf1, sample) + 1;
+ enl2 = xdl_guess_lines(mf2, sample) + 1;
- if (xdl_init_classifier(&cf, enl1 + enl2 + 1, xpp->flags) < 0) {
+ if (!(xpp->flags & XDF_HISTOGRAM_DIFF) &&
+ xdl_init_classifier(&cf, enl1 + enl2 + 1, xpp->flags) < 0) {
return -1;
}
@@ -288,9 +269,11 @@ int xdl_prepare_env(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp,
return -1;
}
- xdl_free_classifier(&cf);
+ if (!(xpp->flags & XDF_HISTOGRAM_DIFF))
+ xdl_free_classifier(&cf);
if (!(xpp->flags & XDF_PATIENCE_DIFF) &&
+ !(xpp->flags & XDF_HISTOGRAM_DIFF) &&
xdl_optimize_ctxs(&xe->xdf1, &xe->xdf2) < 0) {
xdl_free_ctx(&xe->xdf2);
diff --git a/xdiff/xutils.c b/xdiff/xutils.c
index ab65034..0de084e 100644
--- a/xdiff/xutils.c
+++ b/xdiff/xutils.c
@@ -24,10 +24,6 @@
-#define XDL_GUESS_NLINES 256
-
-
-
long xdl_bogosqrt(long n) {
long i;
@@ -71,12 +67,6 @@ void *xdl_mmfile_first(mmfile_t *mmf, long *size)
}
-void *xdl_mmfile_next(mmfile_t *mmf, long *size)
-{
- return NULL;
-}
-
-
long xdl_mmfile_size(mmfile_t *mmf)
{
return mmf->size;
@@ -159,18 +149,12 @@ void *xdl_cha_next(chastore_t *cha) {
}
-long xdl_guess_lines(mmfile_t *mf) {
+long xdl_guess_lines(mmfile_t *mf, long sample) {
long nl = 0, size, tsize = 0;
char const *data, *cur, *top;
if ((cur = data = xdl_mmfile_first(mf, &size)) != NULL) {
- for (top = data + size; nl < XDL_GUESS_NLINES;) {
- if (cur >= top) {
- tsize += (long) (cur - data);
- if (!(cur = data = xdl_mmfile_next(mf, &size)))
- break;
- top = data + size;
- }
+ for (top = data + size; nl < sample && cur < top; ) {
nl++;
if (!(cur = memchr(cur, '\n', top - cur)))
cur = top;
@@ -402,3 +386,34 @@ int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2,
return 0;
}
+
+int xdl_fall_back_diff(xdfenv_t *diff_env, xpparam_t const *xpp,
+ int line1, int count1, int line2, int count2)
+{
+ /*
+ * This probably does not work outside Git, since
+ * we have a very simple mmfile structure.
+ *
+ * Note: ideally, we would reuse the prepared environment, but
+ * the libxdiff interface does not (yet) allow for diffing only
+ * ranges of lines instead of the whole files.
+ */
+ mmfile_t subfile1, subfile2;
+ xdfenv_t env;
+
+ subfile1.ptr = (char *)diff_env->xdf1.recs[line1 - 1]->ptr;
+ subfile1.size = diff_env->xdf1.recs[line1 + count1 - 2]->ptr +
+ diff_env->xdf1.recs[line1 + count1 - 2]->size - subfile1.ptr;
+ subfile2.ptr = (char *)diff_env->xdf2.recs[line2 - 1]->ptr;
+ subfile2.size = diff_env->xdf2.recs[line2 + count2 - 2]->ptr +
+ diff_env->xdf2.recs[line2 + count2 - 2]->size - subfile2.ptr;
+ if (xdl_do_diff(&subfile1, &subfile2, xpp, &env) < 0)
+ return -1;
+
+ memcpy(diff_env->xdf1.rchg + line1 - 1, env.xdf1.rchg, count1);
+ memcpy(diff_env->xdf2.rchg + line2 - 1, env.xdf2.rchg, count2);
+
+ xdl_free_env(&env);
+
+ return 0;
+}
diff --git a/xdiff/xutils.h b/xdiff/xutils.h
index d5de829..714719a 100644
--- a/xdiff/xutils.h
+++ b/xdiff/xutils.h
@@ -33,7 +33,7 @@ void xdl_cha_free(chastore_t *cha);
void *xdl_cha_alloc(chastore_t *cha);
void *xdl_cha_first(chastore_t *cha);
void *xdl_cha_next(chastore_t *cha);
-long xdl_guess_lines(mmfile_t *mf);
+long xdl_guess_lines(mmfile_t *mf, long sample);
int xdl_recmatch(const char *l1, long s1, const char *l2, long s2, long flags);
unsigned long xdl_hash_record(char const **data, char const *top, long flags);
unsigned int xdl_hashbits(unsigned int size);
@@ -41,6 +41,8 @@ int xdl_num_out(char *out, long val);
long xdl_atol(char const *str, char const **next);
int xdl_emit_hunk_hdr(long s1, long c1, long s2, long c2,
const char *func, long funclen, xdemitcb_t *ecb);
+int xdl_fall_back_diff(xdfenv_t *diff_env, xpparam_t const *xpp,
+ int line1, int count1, int line2, int count2);