From 6a2abdc12516cd3801bceef4ccfba399c962a074 Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Fri, 24 Aug 2012 22:48:55 -0700 Subject: [PATCH] apply: compute patch->def_name correctly under -p0 Back when "git apply" was written, we made sure that the user can skip more than the default number of path components (i.e. 1) by giving "-p", but the logic for doing so was built around the notion of "we skip N slashes and stop". This obviously does not work well when running under -p0 where we do not want to skip any, but still want to skip SP/HT that separates the pathnames of preimage and postimage and want to reject absolute pathnames. Stop using "stop_at_slash()", and instead introduce a new helper "skip_tree_prefix()" with similar logic but works correctly even for the -p0 case. This is an ancient bug, but has been masked for a long time because most of the patches are text and have other clues to tell us the name of the preimage and the postimage. Noticed by Colin McCabe. Signed-off-by: Junio C Hamano --- builtin/apply.c | 68 ++++++++++++++++++++++++++--------------- t/t4103-apply-binary.sh | 52 +++++++++++++++++++------------ 2 files changed, 75 insertions(+), 45 deletions(-) diff --git a/builtin/apply.c b/builtin/apply.c index c24dc546d0..2ad8c48207 100644 --- a/builtin/apply.c +++ b/builtin/apply.c @@ -1022,15 +1022,23 @@ static int gitdiff_unrecognized(const char *line, struct patch *patch) return -1; } -static const char *stop_at_slash(const char *line, int llen) +/* + * Skip p_value leading components from "line"; as we do not accept + * absolute paths, return NULL in that case. + */ +static const char *skip_tree_prefix(const char *line, int llen) { - int nslash = p_value; + int nslash; int i; + if (!p_value) + return (llen && line[0] == '/') ? NULL : line; + + nslash = p_value; for (i = 0; i < llen; i++) { int ch = line[i]; if (ch == '/' && --nslash <= 0) - return &line[i]; + return (i == 0) ? NULL : &line[i + 1]; } return NULL; } @@ -1060,12 +1068,11 @@ static char *git_header_name(char *line, int llen) if (unquote_c_style(&first, line, &second)) goto free_and_fail1; - /* advance to the first slash */ - cp = stop_at_slash(first.buf, first.len); - /* we do not accept absolute paths */ - if (!cp || cp == first.buf) + /* strip the a/b prefix including trailing slash */ + cp = skip_tree_prefix(first.buf, first.len); + if (!cp) goto free_and_fail1; - strbuf_remove(&first, 0, cp + 1 - first.buf); + strbuf_remove(&first, 0, cp - first.buf); /* * second points at one past closing dq of name. @@ -1079,22 +1086,21 @@ static char *git_header_name(char *line, int llen) if (*second == '"') { if (unquote_c_style(&sp, second, NULL)) goto free_and_fail1; - cp = stop_at_slash(sp.buf, sp.len); - if (!cp || cp == sp.buf) + cp = skip_tree_prefix(sp.buf, sp.len); + if (!cp) goto free_and_fail1; /* They must match, otherwise ignore */ - if (strcmp(cp + 1, first.buf)) + if (strcmp(cp, first.buf)) goto free_and_fail1; strbuf_release(&sp); return strbuf_detach(&first, NULL); } /* unquoted second */ - cp = stop_at_slash(second, line + llen - second); - if (!cp || cp == second) + cp = skip_tree_prefix(second, line + llen - second); + if (!cp) goto free_and_fail1; - cp++; - if (line + llen - cp != first.len + 1 || + if (line + llen - cp != first.len || memcmp(first.buf, cp, first.len)) goto free_and_fail1; return strbuf_detach(&first, NULL); @@ -1106,10 +1112,9 @@ static char *git_header_name(char *line, int llen) } /* unquoted first name */ - name = stop_at_slash(line, llen); - if (!name || name == line) + name = skip_tree_prefix(line, llen); + if (!name) return NULL; - name++; /* * since the first name is unquoted, a dq if exists must be @@ -1123,10 +1128,9 @@ static char *git_header_name(char *line, int llen) if (unquote_c_style(&sp, second, NULL)) goto free_and_fail2; - np = stop_at_slash(sp.buf, sp.len); - if (!np || np == sp.buf) + np = skip_tree_prefix(sp.buf, sp.len); + if (!np) goto free_and_fail2; - np++; len = sp.buf + sp.len - np; if (len < second - name && @@ -1158,13 +1162,27 @@ static char *git_header_name(char *line, int llen) case '\n': return NULL; case '\t': case ' ': - second = stop_at_slash(name + len, line_len - len); + /* + * Is this the separator between the preimage + * and the postimage pathname? Again, we are + * only interested in the case where there is + * no rename, as this is only to set def_name + * and a rename patch has the names elsewhere + * in an unambiguous form. + */ + if (!name[len + 1]) + return NULL; /* no postimage name */ + second = skip_tree_prefix(name + len + 1, + line_len - (len + 1)); if (!second) return NULL; - second++; - if (second[len] == '\n' && !strncmp(name, second, len)) { + /* + * Does len bytes starting at "name" and "second" + * (that are separated by one HT or SP we just + * found) exactly match? + */ + if (second[len] == '\n' && !strncmp(name, second, len)) return xmemdupz(name, len); - } } } } diff --git a/t/t4103-apply-binary.sh b/t/t4103-apply-binary.sh index dbbf56cba9..1b420e3b5f 100755 --- a/t/t4103-apply-binary.sh +++ b/t/t4103-apply-binary.sh @@ -8,30 +8,28 @@ test_description='git apply handling binary patches ' . ./test-lib.sh -# setup +test_expect_success 'setup' ' + cat >file1 <<-\EOF && + A quick brown fox jumps over the lazy dog. + A tiny little penguin runs around in circles. + There is a flag with Linux written on it. + A slow black-and-white panda just sits there, + munching on his bamboo. + EOF + cat file1 >file2 && + cat file1 >file4 && -cat >file1 <file2 -cat file1 >file4 - -test_expect_success 'setup' " git update-index --add --remove file1 file2 file4 && - git commit -m 'Initial Version' 2>/dev/null && + git commit -m "Initial Version" 2>/dev/null && git checkout -b binary && - perl -pe 'y/x/\000/' file3 && + perl -pe "y/x/\000/" file3 && cat file3 >file4 && git add file2 && - perl -pe 'y/\000/v/' file1 && + perl -pe "y/\000/v/" file1 && rm -f file2 && git update-index --add --remove file1 file2 file3 file4 && - git commit -m 'Second Version' && + git commit -m "Second Version" && git diff-tree -p master binary >B.diff && git diff-tree -p -C master binary >C.diff && @@ -42,17 +40,25 @@ test_expect_success 'setup' " git diff-tree -p --full-index master binary >B-index.diff && git diff-tree -p -C --full-index master binary >C-index.diff && + git diff-tree -p --binary --no-prefix master binary -- file3 >B0.diff && + git init other-repo && - (cd other-repo && - git fetch .. master && - git reset --hard FETCH_HEAD + ( + cd other-repo && + git fetch .. master && + git reset --hard FETCH_HEAD ) -" +' test_expect_success 'stat binary diff -- should not fail.' \ 'git checkout master && git apply --stat --summary B.diff' +test_expect_success 'stat binary -p0 diff -- should not fail.' ' + git checkout master && + git apply --stat -p0 B0.diff +' + test_expect_success 'stat binary diff (copy) -- should not fail.' \ 'git checkout master && git apply --stat --summary C.diff' @@ -143,4 +149,10 @@ test_expect_success 'apply binary diff (copy).' \ git apply --allow-binary-replacement --index CF.diff && test -z "$(git diff --name-status binary)"' +test_expect_success 'apply binary -p0 diff' ' + do_reset && + git apply -p0 --index B0.diff && + test -z "$(git diff --name-status binary -- file3)" +' + test_done