[PATCH 0/4] hash: introduce generic wrappers to update hash contexts

Hi,

this patch series introduces a couple of generic wrappers to update hash contexts. Instead of updating contexts via function pointers provided by the hash algorithm, we now remember the hash algorithm in the context itself. As a result, subsequent calls that update the hash don't need to remember which algorithm they used:

    ```
    struct git_hash_ctx ctx;
    struct object_id oid;

    git_hash_sha1_init(&ctx);
    git_hash_update(&ctx, data);
    git_hash_final_oid(&oid, &ctx);
    ```

This was discussed in [1] and [2].

The series is built on top of master at 3b0d05c4a7 (The fifth batch, 2025-01-29) with tb/unsafe-hashtcleanup at 04292c3796 (hash.h: drop unsafe_ function variants, 2025-01-23) merged into it.

Thanks!

Patrick

[1]: <Z3fhK1ACzJfVehM2@pks.im> [2]: <Z4jyZCAwqOjZ-u2U@pks.im>

---
Patrick Steinhardt (4):
      hash: convert hashing context to a structure
      hash: stop typedeffing the hash context
      hash: provide generic wrappers to update hash contexts
      global: adapt callers to use generic hash context helpers

 builtin/fast-import.c      |  16 +++---
 builtin/index-pack.c       |  19 ++++---
 builtin/patch-id.c         |  14 ++---
 builtin/receive-pack.c     |  18 +++----
 builtin/unpack-objects.c   |  13 +++--
 bulk-checkin.c             |  10 ++--
 csum-file.c                |  16 +++---
 csum-file.h                |   4 +-
 diff.c                     |  34 ++++++------
 diff.h                     |   2 +-
 hash.h                     |  43 +++++++++++----
 http-push.c                |   6 +--
 http.c                     |   6 +--
 http.h                     |   2 +-
 object-file.c              | 130 +++++++++++++++++++++++----------------------
 pack-check.c               |   6 +--
 pack-write.c               |  16 +++---
 read-cache.c               |  26 ++++-----
 rerere.c                   |  18 +++----
 t/helper/test-hash-speed.c |   8 +--
 t/helper/test-hash.c       |   6 +--
 t/unit-tests/u-hash.c      |   6 +--
 trace2/tr2_sid.c           |   6 +--
 23 files changed, 224 insertions(+), 201 deletions(-)

--- base-commit: 16b8e620c866ddbff7e33cc47b9772541285da7f change-id: 20250131-b4-pks-hash-context-direct-aa7acfda3abc