[09/19] object-file: make `buf` parameter of `index_mem()` a constant

Commit Message

Patrick Steinhardt May 29, 2024, 12:44 p.m. UTC

The `buf` parameter of `index_mem()` is a non-constant string. This will
break once we enable `-Wwrite-strings` because we also pass constants
from at least one callsite.

Adapt the parameter to be a constant. As we cannot free the buffer
without casting now, this also requires us to move the lifetime of the
nested buffer around.

Signed-off-by: Patrick Steinhardt <[e-mail]>
---
 object-file.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

Comments

Junio C Hamano May 29, 2024, 8:01 p.m. UTC | #1

Patrick Steinhardt <[e-mail]> writes:

> The `buf` parameter of `index_mem()` is a non-constant string. This will
> break once we enable `-Wwrite-strings` because we also pass constants
> from at least one callsite.
>
> Adapt the parameter to be a constant. As we cannot free the buffer
> without casting now, this also requires us to move the lifetime of the
> nested buffer around.

Makes sense.

Patch

diff --git a/object-file.c b/object-file.c
index c9e374e57e..46ea00ac46 100644
--- a/object-file.c
+++ b/object-file.c
@@ -2483,12 +2483,13 @@  static int hash_format_check_report(struct fsck_options *opts UNUSED,
 }
 
 static int index_mem(struct index_state *istate,
-		     struct object_id *oid, void *buf, size_t size,
+		     struct object_id *oid,
+		     const void *buf, size_t size,
 		     enum object_type type,
 		     const char *path, unsigned flags)
 {
+	struct strbuf nbuf = STRBUF_INIT;
 	int ret = 0;
-	int re_allocated = 0;
 	int write_object = flags & HASH_WRITE_OBJECT;
 
 	if (!type)
@@ -2498,11 +2499,10 @@  static int index_mem(struct index_state *istate,
 	 * Convert blobs to git internal format
 	 */
 	if ((type == OBJ_BLOB) && path) {
-		struct strbuf nbuf = STRBUF_INIT;
 		if (convert_to_git(istate, path, buf, size, &nbuf,
 				   get_conv_flags(flags))) {
-			buf = strbuf_detach(&nbuf, &size);
-			re_allocated = 1;
+			buf = nbuf.buf;
+			size = nbuf.len;
 		}
 	}
 	if (flags & HASH_FORMAT_CHECK) {
@@ -2519,8 +2519,8 @@  static int index_mem(struct index_state *istate,
 		ret = write_object_file(buf, size, type, oid);
 	else
 		hash_object_file(the_hash_algo, buf, size, type, oid);
-	if (re_allocated)
-		free(buf);
+
+	strbuf_release(&nbuf);
 	return ret;
 }