From 2344d47fba45bdddb0801ebf0789935a96e44352 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Thu, 12 Oct 2006 14:22:14 +0200 Subject: [PATCH] diff: fix 2 whitespace issues When whitespace or whitespace change was ignored, the function xdl_recmatch() returned memcmp() style differences, which is wrong, since it should return 0 on non-match. Also, there were three horrible off-by-one bugs, even leading to wrong hashes in the whitespace special handling. The issue was noticed by Ray Lehtiniemi. For good measure, this commit adds a test. Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano --- t/t4015-diff-whitespace.sh | 122 +++++++++++++++++++++++++++++++++++++ xdiff/xutils.c | 29 ++++----- 2 files changed, 134 insertions(+), 17 deletions(-) create mode 100755 t/t4015-diff-whitespace.sh diff --git a/t/t4015-diff-whitespace.sh b/t/t4015-diff-whitespace.sh new file mode 100755 index 0000000000..c945085245 --- /dev/null +++ b/t/t4015-diff-whitespace.sh @@ -0,0 +1,122 @@ +#!/bin/sh +# +# Copyright (c) 2006 Johannes E. Schindelin +# + +test_description='Test special whitespace in diff engine. + +' +. ./test-lib.sh +. ../diff-lib.sh + +# Ray Lehtiniemi's example + +cat << EOF > x +do { + nothing; +} while (0); +EOF + +git-update-index --add x + +cat << EOF > x +do +{ + nothing; +} +while (0); +EOF + +cat << EOF > expect +diff --git a/x b/x +index adf3937..6edc172 100644 +--- a/x ++++ b/x +@@ -1,3 +1,5 @@ +-do { ++do ++{ + nothing; +-} while (0); ++} ++while (0); +EOF + +git-diff > out +test_expect_success "Ray's example without options" 'diff -u expect out' + +git-diff -w > out +test_expect_success "Ray's example with -w" 'diff -u expect out' + +git-diff -b > out +test_expect_success "Ray's example with -b" 'diff -u expect out' + +cat << EOF > x +whitespace at beginning +whitespace change +whitespace in the middle +whitespace at end +unchanged line +CR at end +EOF + +git-update-index x + +cat << EOF > x + whitespace at beginning +whitespace change +white space in the middle +whitespace at end +unchanged line +CR at end +EOF + +cat << EOF > expect +diff --git a/x b/x +index d99af23..8b32fb5 100644 +--- a/x ++++ b/x +@@ -1,6 +1,6 @@ +-whitespace at beginning +-whitespace change +-whitespace in the middle +-whitespace at end ++ whitespace at beginning ++whitespace change ++white space in the middle ++whitespace at end + unchanged line +-CR at end ++CR at end +EOF +git-diff > out +test_expect_success 'another test, without options' 'diff -u expect out' + +cat << EOF > expect +diff --git a/x b/x +index d99af23..8b32fb5 100644 +EOF +git-diff -w > out +test_expect_success 'another test, with -w' 'diff -u expect out' + +cat << EOF > expect +diff --git a/x b/x +index d99af23..8b32fb5 100644 +--- a/x ++++ b/x +@@ -1,6 +1,6 @@ +-whitespace at beginning ++ whitespace at beginning + whitespace change +-whitespace in the middle +-whitespace at end ++white space in the middle ++whitespace at end + unchanged line +-CR at end ++CR at end +EOF +git-diff -b > out +test_expect_success 'another test, with -b' 'diff -u expect out' + +test_done diff --git a/xdiff/xutils.c b/xdiff/xutils.c index f7bdd395ad..9e4bb47ee9 100644 --- a/xdiff/xutils.c +++ b/xdiff/xutils.c @@ -191,36 +191,30 @@ int xdl_recmatch(const char *l1, long s1, const char *l2, long s2, long flags) int i1, i2; if (flags & XDF_IGNORE_WHITESPACE) { - for (i1 = i2 = 0; i1 < s1 && i2 < s2; i1++, i2++) { + for (i1 = i2 = 0; i1 < s1 && i2 < s2; ) { if (isspace(l1[i1])) while (isspace(l1[i1]) && i1 < s1) i1++; - else if (isspace(l2[i2])) + if (isspace(l2[i2])) while (isspace(l2[i2]) && i2 < s2) i2++; - else if (l1[i1] != l2[i2]) - return l2[i2] - l1[i1]; + if (i1 < s1 && i2 < s2 && l1[i1++] != l2[i2++]) + return 0; } - if (i1 >= s1) - return 1; - else if (i2 >= s2) - return -1; + return (i1 >= s1 && i2 >= s2); } else if (flags & XDF_IGNORE_WHITESPACE_CHANGE) { - for (i1 = i2 = 0; i1 < s1 && i2 < s2; i1++, i2++) { + for (i1 = i2 = 0; i1 < s1 && i2 < s2; ) { if (isspace(l1[i1])) { if (!isspace(l2[i2])) - return -1; + return 0; while (isspace(l1[i1]) && i1 < s1) i1++; while (isspace(l2[i2]) && i2 < s2) i2++; - } else if (l1[i1] != l2[i2]) - return l2[i2] - l1[i1]; + } else if (l1[i1++] != l2[i2++]) + return 0; } - if (i1 >= s1) - return 1; - else if (i2 >= s2) - return -1; + return (i1 >= s1 && i2 >= s2); } else return s1 == s2 && !memcmp(l1, l2, s1); @@ -233,7 +227,8 @@ unsigned long xdl_hash_record(char const **data, char const *top, long flags) { for (; ptr < top && *ptr != '\n'; ptr++) { if (isspace(*ptr) && (flags & XDF_WHITESPACE_FLAGS)) { - while (ptr < top && isspace(*ptr) && ptr[1] != '\n') + while (ptr + 1 < top && isspace(ptr[1]) + && ptr[1] != '\n') ptr++; if (flags & XDF_IGNORE_WHITESPACE_CHANGE) { ha += (ha << 5);