pack-write: fix return parameter of write_rev_file_order()

While the return parameter of `write_rev_file_order()` is a string
constant, the function may indeed return an allocated string when its
first parameter is a `NULL` pointer. This makes for a confusing calling
convention, where callers need to be aware of these intricate ownership
rules and cast away the constness to free the string in some cases.

Adapt the function and its caller `write_rev_file()` to always return an
allocated string and adapt callers to always free the return value.

Note that this requires us to also adapt `rename_tmp_packfile()`, which
compares the pointers to packfile data with each other. Now that the
path of the reverse index file gets allocated unconditionally the check
will always fail. This is fixed by using strcmp(3P) instead, which also
feels way less fragile.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Patrick Steinhardt
2024-09-30 11:14:08 +02:00
committed by Junio C Hamano
parent 6512d6e473
commit 2f0ee051dd
5 changed files with 31 additions and 26 deletions

View File

@ -649,7 +649,7 @@ static void write_midx_reverse_index(char *midx_name, unsigned char *midx_hash,
struct write_midx_context *ctx)
{
struct strbuf buf = STRBUF_INIT;
const char *tmp_file;
char *tmp_file;
trace2_region_enter("midx", "write_midx_reverse_index", the_repository);
@ -662,6 +662,7 @@ static void write_midx_reverse_index(char *midx_name, unsigned char *midx_hash,
die(_("cannot store reverse index file"));
strbuf_release(&buf);
free(tmp_file);
trace2_region_leave("midx", "write_midx_reverse_index", the_repository);
}