git/list[1] front-page[2] threads[3] people[4] search[5] about
 

[PATCH v5 1/2] ref-filter: handle CRLF at end-of-line more gracefully

From
Philippe Blain via GitGitGadget <gitgitgadget@gmail.com>
Date
Oct 29, 2020, 12:48 UTC
Message-ID
<06231c315ff6e5a1065b5a77350d7cdc307f760b.1603975709.git.gitgitgadget@gmail.com>
In-Reply-To
<pull.576.v5.git.1603975709.gitgitgadget@gmail.com>
From: Philippe Blain <levraiphilippeblain@gmail.com>

The ref-filter code does not correctly handle commit or tag messages that use CRLF as the line terminator. Such messages can be created with the `--cleanup=verbatim` option of `git commit` and `git tag`, or by using `git commit-tree` directly.

The function `find_subpos` in ref-filter.c looks for two consecutive LFs to find the end of the subject line, a sequence which is absent in messages using CRLF. This results in the whole message being parsed as the subject line (`%(contents:subject)`), and the body of the message (`%(contents:body)`) being empty.

Moreover, in `copy_subject`, which wants to return the subject as a single line, '\n' is replaced by space, but '\r' is untouched.

This impacts the output of `git branch`, `git tag` and `git for-each-ref`.

This behaviour is a regression for `git branch --verbose`, which bisects down to 949af0684c (branch: use ref-filter printing APIs, 2017-01-10).

Adjust the ref-filter code to be more lenient by hardening the logic in `copy_subject` and `find_subpos` to correctly parse messages containing CRLF.

Add a new test script, 't3920-crlf-messages.sh', to test the behaviour of commands using either the ref-filter or the pretty APIs with messages using CRLF line endings. The function `test_crlf_subject_body_and_contents` can be used to test that the `--format` option of `branch`, `tag`, `for-each-ref`, `log` and `show` correctly displays the subject, body and raw content of commit and tag messages using CRLF. Test the output of `branch`, `tag` and `for-each-ref` with such commits.

Helped-by: Junio C Hamano <gitster@pobox.com>
Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com>
---
 ref-filter.c             |  36 ++++++++-----
 t/t3920-crlf-messages.sh | 108 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 130 insertions(+), 14 deletions(-)
 create mode 100755 t/t3920-crlf-messages.sh
diff --git a/ref-filter.c b/ref-filter.c
index c62f6b4822..6476686fea 100644
--- a/ref-filter.c
+++ b/ref-filter.c
@@ -1097,14 +1097,19 @@ static const char *copy_email(const char *buf, struct used_atom *atom)
 
 static char *copy_subject(const char *buf, unsigned long len)
 {
-	char *r = xmemdupz(buf, len);
+	struct strbuf sb = STRBUF_INIT;
 	int i;
 
-	for (i = 0; i < len; i++)
-		if (r[i] == '\n')
-			r[i] = ' ';
+	for (i = 0; i < len; i++) {
+		if (buf[i] == '\r' && i + 1 < len && buf[i + 1] == '\n')
+			continue; /* ignore CR in CRLF */
 
-	return r;
+		if (buf[i] == '\n')
+			strbuf_addch(&sb, ' ');
+		else
+			strbuf_addch(&sb, buf[i]);
+	}
+	return strbuf_detach(&sb, NULL);
 }
 
 static void grab_date(const char *buf, struct atom_value *v, const char *atomname)
@@ -1228,20 +1233,23 @@ static void find_subpos(const char *buf,
 
 	/* subject is first non-empty line */
 	*sub = buf;
-	/* subject goes to first empty line */
-	while (buf < *sig && *buf && *buf != '\n') {
-		eol = strchrnul(buf, '\n');
-		if (*eol)
-			eol++;
-		buf = eol;
-	}
+	/* subject goes to first empty line before signature begins */
+	if ((eol = strstr(*sub, "\n\n"))) {
+		eol = eol < *sig ? eol : *sig;
+	/* check if message uses CRLF */
+	} else if (! (eol = strstr(*sub, "\r\n\r\n"))) {
+		/* treat whole message as subject */
+		eol = strrchr(*sub, '\0');
+	}
+	buf = eol;
 	*sublen = buf - *sub;
 	/* drop trailing newline, if present */
-	if (*sublen && (*sub)[*sublen - 1] == '\n')
+	while (*sublen && ((*sub)[*sublen - 1] == '\n' ||
+			   (*sub)[*sublen - 1] == '\r'))
 		*sublen -= 1;
 
 	/* skip any empty lines */
-	while (*buf == '\n')
+	while (*buf == '\n' || *buf == '\r')
 		buf++;
 	*body = buf;
 	*bodylen = strlen(buf);
diff --git a/t/t3920-crlf-messages.sh b/t/t3920-crlf-messages.sh
new file mode 100755
index 0000000000..3f0ce02c3f
--- /dev/null
+++ b/t/t3920-crlf-messages.sh
@@ -0,0 +1,108 @@
+#!/bin/sh
+
+test_description='Test ref-filter and pretty APIs for commit and tag messages using CRLF'
+. ./test-lib.sh
+
+LIB_CRLF_BRANCHES=""
+
+create_crlf_ref () {
+	branch="$1" &&
+	cat >.crlf-orig-$branch.txt &&
+	cat .crlf-orig-$branch.txt | append_cr >.crlf-message-$branch.txt &&
+	grep 'Subject' .crlf-orig-$branch.txt | tr '\n' ' ' | sed 's/[ ]*$//' | tr -d '\n' >.crlf-subject-$branch.txt &&
+	grep 'Body' .crlf-message-$branch.txt >.crlf-body-$branch.txt || true &&
+	LIB_CRLF_BRANCHES="${LIB_CRLF_BRANCHES} ${branch}" &&
+	test_tick &&
+	hash=$(git commit-tree HEAD^{tree} -p HEAD -F .crlf-message-${branch}.txt) &&
+	git branch ${branch} ${hash} &&
+	git tag tag-${branch} ${branch} -F .crlf-message-${branch}.txt --cleanup=verbatim
+}
+
+create_crlf_refs () {
+	create_crlf_ref crlf <<-\EOF &&
+	Subject first line
+
+	Body first line
+	Body second line
+	EOF
+	create_crlf_ref crlf-empty-lines-after-subject <<-\EOF &&
+	Subject first line
+
+
+	Body first line
+	Body second line
+	EOF
+	create_crlf_ref crlf-two-line-subject <<-\EOF &&
+	Subject first line
+	Subject second line
+
+	Body first line
+	Body second line
+	EOF
+	create_crlf_ref crlf-two-line-subject-no-body <<-\EOF &&
+	Subject first line
+	Subject second line
+	EOF
+	create_crlf_ref crlf-two-line-subject-no-body-trailing-newline <<-\EOF
+	Subject first line
+	Subject second line
+
+	EOF
+}
+
+test_crlf_subject_body_and_contents() {
+	command_and_args="$@" &&
+	command=$1 &&
+	if test ${command} = "branch" || test ${command} = "for-each-ref" || test ${command} = "tag"
+	then
+		atoms="(contents:subject) (contents:body) (contents)"
+	elif test ${command} = "log" || test ${command} = "show"
+	then
+		atoms="s b B"
+	fi &&
+	files="subject body message" &&
+	while test -n "${atoms}"
+	do
+		set ${atoms} && atom=$1 && shift && atoms="$*" &&
+		set ${files} &&	file=$1 && shift && files="$*" &&
+		test_expect_success "${command}: --format='%${atom}' works with messages using CRLF" "
+			rm -f expect &&
+			for ref in ${LIB_CRLF_BRANCHES}
+			do
+				cat .crlf-${file}-\"\${ref}\".txt >>expect &&
+				printf \"\n\" >>expect
+			done &&
+			git $command_and_args --format=\"%${atom}\" >actual &&
+			test_cmp expect actual
+		"
+	done
+}
+
+
+test_expect_success 'Setup refs with commit and tag messages using CRLF' '
+	test_commit inital &&
+	create_crlf_refs
+'
+
+test_expect_success 'branch: --verbose works with messages using CRLF' '
+	rm -f expect &&
+	for branch in $LIB_CRLF_BRANCHES
+	do
+		printf "  " >>expect &&
+		cat .crlf-subject-${branch}.txt >>expect &&
+		printf "\n" >>expect
+	done &&
+	git branch -v >tmp &&
+	# Remove first two columns, and the line for the currently checked out branch
+	current=$(git branch --show-current) &&
+	grep -v $current <tmp | awk "{\$1=\$2=\"\"}1"  >actual &&
+	test_cmp expect actual
+'
+
+test_crlf_subject_body_and_contents branch --list crlf*
+
+test_crlf_subject_body_and_contents tag --list tag-crlf*
+
+test_crlf_subject_body_and_contents for-each-ref refs/heads/crlf*
+
+test_done
-- 
gitgitgadget
Previous: Philippe Blain via GitGitGadgetNext: Philippe Blain via GitGitGadget
Message 37 of 38 in “Teach ref-filter API to correctly handle CRLF in messages”
  1. 0/3 Teach ref-filter API to correctly handle CRLF in messagesPhilippe Blain via GitGitGadget, Mar 8, 2020
  2. 3/3 log: add tests for messages containing CRLF to t4202Philippe Blain via GitGitGadget, Mar 8, 2020
  3. 1/3 t: add lib-crlf-messages.sh for messages containing CRLFPhilippe Blain via GitGitGadget, Mar 8, 2020
  4. 2/3 ref-filter: teach the API to correctly handle CRLFPhilippe Blain via GitGitGadget, Mar 8, 2020
  5. Junio C HamanoMar 9, 2020
  6. Philippe BlainMar 10, 2020
  7. 0/3 Teach ref-filter API to correctly handle CRLF in messagesPhilippe Blain via GitGitGadget, Mar 10, 2020
  8. 1/3 t: add lib-crlf-messages.sh for messages containing CRLFPhilippe Blain via GitGitGadget, Mar 10, 2020
  9. 2/3 ref-filter: fix the API to correctly handle CRLFPhilippe Blain via GitGitGadget, Mar 10, 2020
  10. Junio C HamanoMar 10, 2020
  11. 3/3 log: add tests for messages containing CRLF to t4202Philippe Blain via GitGitGadget, Mar 10, 2020
  12. Junio C HamanoMar 10, 2020
  13. Junio C HamanoMar 10, 2020
  14. 0/3 ref-filter: handle CRLF at end-of-line more gracefullyPhilippe Blain via GitGitGadget, Oct 12, 2020
  15. 2/3 ref-filter: handle CRLF at end-of-line more gracefullyPhilippe Blain via GitGitGadget, Oct 12, 2020
  16. Junio C HamanoOct 12, 2020
  17. Philippe BlainOct 14, 2020
  18. 1/3 t: add lib-crlf-messages.sh for messages containing CRLFPhilippe Blain via GitGitGadget, Oct 12, 2020
  19. Junio C HamanoOct 12, 2020
  20. Philippe BlainOct 14, 2020
  21. Eric SunshineOct 12, 2020
  22. Philippe BlainOct 14, 2020
  23. Eric SunshineOct 14, 2020
  24. Philippe BlainOct 14, 2020
  25. Eric SunshineOct 14, 2020
  26. Philippe BlainOct 22, 2020
  27. 3/3 log, show: add tests for messages containing CRLFPhilippe Blain via GitGitGadget, Oct 12, 2020
  28. 0/2 ref-filter: handle CRLF at end-of-line more gracefullyPhilippe Blain via GitGitGadget, Oct 22, 2020
  29. 2/2 log, show: add tests for messages containing CRLFPhilippe Blain via GitGitGadget, Oct 22, 2020
  30. Philippe BlainOct 22, 2020
  31. 1/2 ref-filter: handle CRLF at end-of-line more gracefullyPhilippe Blain via GitGitGadget, Oct 22, 2020
  32. Junio C HamanoOct 23, 2020
  33. Philippe BlainOct 23, 2020
  34. Junio C HamanoOct 28, 2020
  35. Philippe BlainOct 29, 2020
  36. 0/2 ref-filter: handle CRLF at end-of-line more gracefullyPhilippe Blain via GitGitGadget, Oct 29, 2020
  37. 1/2 ref-filter: handle CRLF at end-of-line more gracefullyPhilippe Blain via GitGitGadget, Oct 29, 2020
  38. 2/2 log, show: add tests for messages containing CRLFPhilippe Blain via GitGitGadget, Oct 29, 2020

Read the whole thread, see it on lore, or plain text.

$ cat FOOTERMessages come from the public archive at lore.kernel.org/git, fetched every hour. The front page is chosen and written each morning by an AI editor and can be wrong; the threads themselves are the record. About and API. For agents: an MCP server at https://gitlist.dev/mcp, and any thread, story or person page as Markdown by adding .md to its URL (or sending Accept: text/markdown). Details in /llms.txt.