Merge branch 'jk/read-in-full'

Code clean-up to prevent future mistakes by copying and pasting
code that checks the result of read_in_full() function.

* jk/read-in-full:
  worktree: check the result of read_in_full()
  worktree: use xsize_t to access file size
  distinguish error versus short read from read_in_full()
  avoid looking at errno for short read_in_full() returns
  prefer "!=" when checking read_in_full() result
  notes-merge: drop dead zero-write code
  files-backend: prefer "0" for write_in_full() error check

1 files changed, 6 insertions, 1 deletions

diff --git a/pack-write.c b/pack-write.c
index a333ec6754..fea6284192 100644
--- a/pack-write.c
+++ b/pack-write.c
@@ -213,14 +213,19 @@ void fixup_pack_header_footer(int pack_fd,
 	git_SHA_CTX old_sha1_ctx, new_sha1_ctx;
 	struct pack_header hdr;
 	char *buf;
+	ssize_t read_result;
 
 	git_SHA1_Init(&old_sha1_ctx);
 	git_SHA1_Init(&new_sha1_ctx);
 
 	if (lseek(pack_fd, 0, SEEK_SET) != 0)
 		die_errno("Failed seeking to start of '%s'", pack_name);
-	if (read_in_full(pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr))
+	read_result = read_in_full(pack_fd, &hdr, sizeof(hdr));
+	if (read_result < 0)
 		die_errno("Unable to reread header of '%s'", pack_name);
+	else if (read_result != sizeof(hdr))
+		die_errno("Unexpected short read for header of '%s'",
+			  pack_name);
 	if (lseek(pack_fd, 0, SEEK_SET) != 0)
 		die_errno("Failed seeking to start of '%s'", pack_name);
 	git_SHA1_Update(&old_sha1_ctx, &hdr, sizeof(hdr));