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[PATCH 1/3] unpack: replace xwrite() loop with write_in_full()

From
Junio C Hamano <gitster@pobox.com>
Date
Mar 2, 2024, 19:03 UTC
Message-ID
<20240302190348.3946569-2-gitster@pobox.com>
In-Reply-To
<20240302190348.3946569-1-gitster@pobox.com>

We have two packfile stream consumers, index-pack and unpack-objects, that allow excess payload after the packfile stream data. Their code to relay excess data hasn't changed significantly since their original implementation that appeared in 67e5a5ec (git-unpack-objects: re-write to read from stdin, 2005-06-28) and 9bee2478 (mimic unpack-objects when --stdin is used with index-pack, 2006-10-25).

These code blocks contain hand-rolled loops using xwrite(), written before our write_in_full() helper existed. This helper now provides the same functionality.

Replace these loops with write_in_full() for shorter, clearer code. Update related variables accordingly.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 builtin/index-pack.c     | 17 +++--------------
 builtin/unpack-objects.c |  8 +-------
 2 files changed, 4 insertions(+), 21 deletions(-)
diff --git a/builtin/index-pack.c b/builtin/index-pack.c
index a3a37bd215..856428fef9 100644
--- a/builtin/index-pack.c
+++ b/builtin/index-pack.c
@@ -1524,14 +1524,12 @@ static void final(const char *final_pack_name, const char *curr_pack_name,
 	struct strbuf pack_name = STRBUF_INIT;
 	struct strbuf index_name = STRBUF_INIT;
 	struct strbuf rev_index_name = STRBUF_INIT;
-	int err;
 
 	if (!from_stdin) {
 		close(input_fd);
 	} else {
 		fsync_component_or_die(FSYNC_COMPONENT_PACK, output_fd, curr_pack_name);
-		err = close(output_fd);
-		if (err)
+		if (close(output_fd))
 			die_errno(_("error while closing pack file"));
 	}
 
@@ -1566,17 +1564,8 @@ static void final(const char *final_pack_name, const char *curr_pack_name,
 		write_or_die(1, buf.buf, buf.len);
 		strbuf_release(&buf);
 
-		/*
-		 * Let's just mimic git-unpack-objects here and write
-		 * the last part of the input buffer to stdout.
-		 */
-		while (input_len) {
-			err = xwrite(1, input_buffer + input_offset, input_len);
-			if (err <= 0)
-				break;
-			input_len -= err;
-			input_offset += err;
-		}
+		/* Write the last part of the buffer to stdout */
+		write_in_full(1, input_buffer + input_offset, input_len);
 	}
 
 	strbuf_release(&rev_index_name);
diff --git a/builtin/unpack-objects.c b/builtin/unpack-objects.c
index e0a701f2b3..f1c85a00ae 100644
--- a/builtin/unpack-objects.c
+++ b/builtin/unpack-objects.c
@@ -679,13 +679,7 @@ int cmd_unpack_objects(int argc, const char **argv, const char *prefix UNUSED)
 	use(the_hash_algo->rawsz);
 
 	/* Write the last part of the buffer to stdout */
-	while (len) {
-		int ret = xwrite(1, buffer + offset, len);
-		if (ret <= 0)
-			break;
-		len -= ret;
-		offset += ret;
-	}
+	write_in_full(1, buffer + offset, len);
 
 	/* All done */
 	return has_errors;
-- 
2.44.0-84-gb387623c12
Previous: Junio C HamanoNext: Patrick Steinhardt
Message 2 of 7 in “Auditing use of xwrite()”
  1. 0/3 Auditing use of xwrite()Junio C Hamano, Mar 2, 2024
  2. 1/3 unpack: replace xwrite() loop with write_in_full()Junio C Hamano, Mar 2, 2024
  3. Patrick SteinhardtMar 4, 2024
  4. Junio C HamanoMar 4, 2024
  5. Junio C HamanoMar 4, 2024
  6. 3/3 repack: check error writing to pack-objects subprocessJunio C Hamano, Mar 2, 2024
  7. 2/3 sideband: avoid short write(2)Junio C Hamano, Mar 2, 2024

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