[PATCH 08/16] git-zlib: use `struct z_stream_s` instead of typedef
- From
Patrick Steinhardt <ps@pks.im>
- Date
- Mar 31, 2025, 08:41 UTC
- Message-ID
- <20250331-pks-reftable-polishing-v1-8-ebed5247434c@pks.im>
- In-Reply-To
- <20250331-pks-reftable-polishing-v1-0-ebed5247434c@pks.im>
Throughout the Git codebase we're using the typedeffed version of `z_stream`, which maps to `struct z_stream_s`. By using a typedef instead of the struct it becomes somewhat harder to predeclare the symbol so that headers depending on the struct can do so without having to pull in "zlib-compat.h".
We don't yet have users that would really care about this: the only users that declare `z_stream` as a pointer are in "reftable/block.h", which is a header that is internal to the reftable library. But in the next step we're going to expose the `struct reftable_block` publicly, and that struct does contain a pointer to `z_stream`. And as the public header shouldn't depend on "reftable/system.h", which is an internal implementation detail, we won't have the typedef for `z_stream` readily available.
Prepare for this change by using `struct z_stream_s` throughout our code base. In case zlib-ng is used we use a define to map from `z_stream_s` to `zng_stream_s`.
Drop the pre-declaration of `struct z_stream` while at it. This struct does not exist in the first place, and the declaration wasn't needed because "reftable/block.h" already includes "reftable/basics.h" which transitively includes "reftable/system.h" and thus "git-zlib.h".
Signed-off-by: Patrick Steinhardt <ps@pks.im> --- Documentation/howto/recover-corrupted-object-harder.adoc | 4 ++-- compat/zlib-compat.h | 4 ++-- git-zlib.h | 2 +- reftable/block.h | 6 ++---- 4 files changed, 7 insertions(+), 9 deletions(-)
diff --git a/Documentation/howto/recover-corrupted-object-harder.adoc b/Documentation/howto/recover-corrupted-object-harder.adoc index 5efb4fe81ff..86a1ba75cf9 100644 --- a/Documentation/howto/recover-corrupted-object-harder.adoc +++ b/Documentation/howto/recover-corrupted-object-harder.adoc @@ -125,7 +125,7 @@ static int try_zlib(unsigned char *buf, int len) { /* make this absurdly large so we don't have to loop */ static unsigned char out[1024*1024]; - z_stream z; + struct z_stream_s z; int ret; memset(&z, 0, sizeof(z)); @@ -278,7 +278,7 @@ int main(int argc, char **argv) static unsigned char buf[25 * 1024 * 1024]; static unsigned char out[25 * 1024 * 1024]; int len; - z_stream z; + struct z_stream_s z; int ret; len = read(0, buf, sizeof(buf)); diff --git a/compat/zlib-compat.h b/compat/zlib-compat.h index 0c60e3af331..ac082766229 100644 --- a/compat/zlib-compat.h +++ b/compat/zlib-compat.h @@ -4,8 +4,8 @@ #ifdef HAVE_ZLIB_NG # include <zlib-ng.h> -# define z_stream zng_stream -#define gz_header_s zng_gz_header_s +# define z_stream_s zng_stream_s +# define gz_header_s zng_gz_header_s # define crc32(crc, buf, len) zng_crc32(crc, buf, len) diff --git a/git-zlib.h b/git-zlib.h index 1e8d9aabcb4..0e66fefa8c9 100644 --- a/git-zlib.h +++ b/git-zlib.h @@ -4,7 +4,7 @@ #include "compat/zlib-compat.h" typedef struct git_zstream { - z_stream z; + struct z_stream_s z; unsigned long avail_in; unsigned long avail_out; unsigned long total_in; diff --git a/reftable/block.h b/reftable/block.h index 880e2e61938..75bc10f63a3 100644 --- a/reftable/block.h +++ b/reftable/block.h @@ -18,7 +18,7 @@ * allocation overhead. */ struct block_writer { - z_stream *zstream; + struct z_stream_s *zstream; unsigned char *compressed; size_t compressed_cap; @@ -62,8 +62,6 @@ int block_writer_finish(struct block_writer *w); /* clears out internally allocated block_writer members. */ void block_writer_release(struct block_writer *bw); -struct z_stream; - /* * A block part of a reftable. Contains records as well as some metadata * describing them. @@ -78,7 +76,7 @@ struct reftable_block { uint32_t hash_size; /* Uncompressed data for log entries. */ - z_stream *zstream; + struct z_stream_s *zstream; unsigned char *uncompressed_data; size_t uncompressed_cap;
-- 2.49.0.604.gff1f9ca942.dirty