[PATCH v2 5/5] patch-id: tighten code to detect the patch header
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Jul 30, 2024, 01:17 UTC
- Message-ID
- <20240730011738.4032377-6-gitster@pobox.com>
- In-Reply-To
- <20240730011738.4032377-1-gitster@pobox.com>
The get_one_patchid() function unconditionally takes a line that matches the patch header (namely, a line that begins with a full object name, possibly prefixed by "commit" or "From" plus a space) as the beginning of a patch. Even when it is *not* looking for one (namely, when the previous call found the patch header and returned, and then we are called again to skip the log message and process the patch whose header was found by the previous invocation).
As a consequence, a line in the commit log message that begins with one of these patterns can be mistaken to start another patch, with current message entirely skipped (because we haven't even reached the patch at all).
Allow the caller to tell us if it called us already and saw the patch header (in which case we shouldn't be looking for another one, until we see the "diff" part of the patch; instead we simply should be skipping these lines as part of the commit log message), and skip the header processing logic when that is the case. In the helper function, it also needs to flip this "are we looking for a header?" bit, once it finished skipping the commit log message and started processing the patches, as the patch header of the _next_ message is the only clue in the input that the current patch is done.
Signed-off-by: Junio C Hamano <gitster@pobox.com> --- builtin/patch-id.c | 49 +++++++++++++++++++++++++++++++++------------ t/t4204-patch-id.sh | 17 ++++++++++++++++ 2 files changed, 53 insertions(+), 13 deletions(-)
diff --git a/builtin/patch-id.c b/builtin/patch-id.c index a2fdc0505d..f2e8feb6d3 100644 --- a/builtin/patch-id.c +++ b/builtin/patch-id.c @@ -60,10 +60,17 @@ static int scan_hunk_header(const char *p, int *p_before, int *p_after) /* * flag bits to control get_one_patchid()'s behaviour. + * + * STABLE/VERBATIM are given from the command line option as + * --stable/--verbatim. FIND_HEADER conveys the internal state + * maintained by the caller to allow the function to avoid mistaking + * lines of log message before seeing the "diff" part as the beginning + * of the next patch. */ enum { GOPID_STABLE = (1<<0), /* --stable */ GOPID_VERBATIM = (1<<1), /* --verbatim */ + GOPID_FIND_HEADER = (1<<2), /* stop at the beginning of patch message */ }; static int get_one_patchid(struct object_id *next_oid, struct object_id *result, @@ -71,6 +78,7 @@ static int get_one_patchid(struct object_id *next_oid, struct object_id *result, { int stable = flags & GOPID_STABLE; int verbatim = flags & GOPID_VERBATIM; + int find_header = flags & GOPID_FIND_HEADER; int patchlen = 0, found_next = 0; int before = -1, after = -1; int diff_is_binary = 0; @@ -86,26 +94,39 @@ static int get_one_patchid(struct object_id *next_oid, struct object_id *result, int len; /* - * If we see a line that begins with "<object name>", - * "commit <object name>" or "From <object name>", it is - * the beginning of a patch. Return to the caller, as - * we are done with the one we have been processing. + * The caller hasn't seen us find a patch header and + * return to it, or we have started processing patch + * and may encounter the beginning of the next patch. */ - if (skip_prefix(line, "commit ", &p)) - ; - else if (skip_prefix(line, "From ", &p)) - ; - if (!get_oid_hex(p, next_oid)) { - if (verbatim) - the_hash_algo->update_fn(&ctx, line, strlen(line)); - found_next = 1; - break; + if (find_header) { + /* + * If we see a line that begins with "<object name>", + * "commit <object name>" or "From <object name>", it is + * the beginning of a patch. Return to the caller, as + * we are done with the one we have been processing. + */ + if (skip_prefix(line, "commit ", &p)) + ; + else if (skip_prefix(line, "From ", &p)) + ; + if (!get_oid_hex(p, next_oid)) { + if (verbatim) + the_hash_algo->update_fn(&ctx, line, strlen(line)); + found_next = 1; + break; + } } /* Ignore commit comments */ if (!patchlen && !starts_with(line, "diff ")) continue; + /* + * We are past the commit log message. Prepare to + * stop at the beginning of the next patch header. + */ + find_header = 1; + /* Parsing diff header? */ if (before == -1) { if (starts_with(line, "GIT binary patch") || @@ -201,11 +222,13 @@ static void generate_id_list(unsigned flags) struct strbuf line_buf = STRBUF_INIT; oidclr(&oid); + flags |= GOPID_FIND_HEADER; while (!feof(stdin)) { patchlen = get_one_patchid(&n, &result, &line_buf, flags); if (patchlen) flush_current_id(&oid, &result); oidcpy(&oid, &n); + flags &= ~GOPID_FIND_HEADER; } strbuf_release(&line_buf); } diff --git a/t/t4204-patch-id.sh b/t/t4204-patch-id.sh index 1627fdda1b..b1d98d4110 100755 --- a/t/t4204-patch-id.sh +++ b/t/t4204-patch-id.sh @@ -137,6 +137,23 @@ test_expect_success 'patch-id computes the same for various formats' ' test_cmp actual expect ' +hash=$(git rev-parse same:) +for cruft in "$hash" "commit $hash is bad" "From $hash status" +do + test_expect_success "patch-id with <$cruft> in log message" ' + git format-patch -1 --stdout same >patch-0 && + git patch-id <patch-0 >expect && + + { + sed -e "/^$/q" patch-0 && + printf "random message\n%s\n\n" "$cruft" && + sed -e "1,/^$/d" patch-0 + } >patch-cruft && + git patch-id <patch-cruft >actual && + test_cmp actual expect + ' +done + test_expect_success 'whitespace is irrelevant in footer' ' get_patch_id main && git checkout same &&
-- 2.46.0-69-gd0749fd195