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[PATCH 16/32] read-cache: save index SHA-1 after reading

From
Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Date
Jun 13, 2014, 12:19 UTC
Message-ID
<1402661991-14977-17-git-send-email-pclouds@gmail.com>
In-Reply-To
<1402661991-14977-1-git-send-email-pclouds@gmail.com>

Also update SHA-1 after writing. If we do not do that, the second read_index() will see "initialized" variable already set and not read .git/index again, which is fine, except istate->sha1 now has a stale value.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 cache.h        | 1 +
 read-cache.c   | 6 ++++--
 unpack-trees.c | 1 +
 3 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/cache.h b/cache.h
index bf09d1c..41cdcd0 100644
--- a/cache.h
+++ b/cache.h
@@ -286,6 +286,7 @@ struct index_state {
 		 initialized : 1;
 	struct hashmap name_hash;
 	struct hashmap dir_hash;
+	unsigned char sha1[20];
 };
 
 extern struct index_state the_index;
diff --git a/read-cache.c b/read-cache.c
index d1ad227..b4653c0 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -1481,6 +1481,7 @@ int read_index_from(struct index_state *istate, const char *path)
 	if (verify_hdr(hdr, mmap_size) < 0)
 		goto unmap;
 
+	hashcpy(istate->sha1, (const unsigned char *)hdr + mmap_size - 20);
 	istate->version = ntohl(hdr->hdr_version);
 	istate->cache_nr = ntohl(hdr->hdr_entries);
 	istate->cache_alloc = alloc_nr(istate->cache_nr);
@@ -1616,7 +1617,7 @@ static int write_index_ext_header(git_SHA_CTX *context, int fd,
 		(ce_write(context, fd, &sz, 4) < 0)) ? -1 : 0;
 }
 
-static int ce_flush(git_SHA_CTX *context, int fd)
+static int ce_flush(git_SHA_CTX *context, int fd, unsigned char *sha1)
 {
 	unsigned int left = write_buffer_len;
 
@@ -1634,6 +1635,7 @@ static int ce_flush(git_SHA_CTX *context, int fd)
 
 	/* Append the SHA1 signature at the end */
 	git_SHA1_Final(write_buffer + left, context);
+	hashcpy(sha1, write_buffer + left);
 	left += 20;
 	return (write_in_full(fd, write_buffer, left) != left) ? -1 : 0;
 }
@@ -1872,7 +1874,7 @@ static int do_write_index(struct index_state *istate, int newfd)
 			return -1;
 	}
 
-	if (ce_flush(&c, newfd) || fstat(newfd, &st))
+	if (ce_flush(&c, newfd, istate->sha1) || fstat(newfd, &st))
 		return -1;
 	istate->timestamp.sec = (unsigned int)st.st_mtime;
 	istate->timestamp.nsec = ST_MTIME_NSEC(st);
diff --git a/unpack-trees.c b/unpack-trees.c
index 26f65c7..f594932 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c
@@ -1046,6 +1046,7 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
 	o->result.timestamp.sec = o->src_index->timestamp.sec;
 	o->result.timestamp.nsec = o->src_index->timestamp.nsec;
 	o->result.version = o->src_index->version;
+	hashcpy(o->result.sha1, o->src_index->sha1);
 	o->merge_size = len;
 	mark_all_ce_unused(o->src_index);
 
-- 
1.9.1.346.ga2b5940
Previous: Nguyễn Thái Ngọc DuyNext: Nguyễn Thái Ngọc Duy
Message 17 of 33 in “Split index resend”
  1. 00/32 Split index resendNguyễn Thái Ngọc Duy, Jun 13, 2014
  2. 01/32 ewah: fix constness of ewah_read_mmapNguyễn Thái Ngọc Duy, Jun 13, 2014
  3. 02/32 ewah: delete unused ewah_read_mmap_native declarationNguyễn Thái Ngọc Duy, Jun 13, 2014
  4. 03/32 sequencer: do not update/refresh index if the lock cannot be heldNguyễn Thái Ngọc Duy, Jun 13, 2014
  5. 04/32 read-cache: new API write_locked_index instead of write_index/write_cacheNguyễn Thái Ngọc Duy, Jun 13, 2014
  6. 05/32 read-cache: relocate and unexport commit_locked_index()Nguyễn Thái Ngọc Duy, Jun 13, 2014
  7. 06/32 read-cache: store in-memory flags in the first 12 bits of ce_flagsNguyễn Thái Ngọc Duy, Jun 13, 2014
  8. 07/32 read-cache: be strict about "changed" in remove_marked_cache_entries()Nguyễn Thái Ngọc Duy, Jun 13, 2014
  9. 08/32 read-cache: be specific what part of the index has changedNguyễn Thái Ngọc Duy, Jun 13, 2014
  10. 09/32 update-index: be specific what part of the index has changedNguyễn Thái Ngọc Duy, Jun 13, 2014
  11. 10/32 resolve-undo: be specific what part of the index has changedNguyễn Thái Ngọc Duy, Jun 13, 2014
  12. 11/32 unpack-trees: be specific what part of the index has changedNguyễn Thái Ngọc Duy, Jun 13, 2014
  13. 12/32 cache-tree: mark istate->cache_changed on cache tree invalidationNguyễn Thái Ngọc Duy, Jun 13, 2014
  14. 13/32 cache-tree: mark istate->cache_changed on cache tree updateNguyễn Thái Ngọc Duy, Jun 13, 2014
  15. 14/32 cache-tree: mark istate->cache_changed on prime_cache_tree()Nguyễn Thái Ngọc Duy, Jun 13, 2014
  16. 15/32 entry.c: update cache_changed if refresh_cache is set in checkout_entry()Nguyễn Thái Ngọc Duy, Jun 13, 2014
  17. 16/32 read-cache: save index SHA-1 after readingNguyễn Thái Ngọc Duy, Jun 13, 2014
  18. 17/32 read-cache: split-index modeNguyễn Thái Ngọc Duy, Jun 13, 2014
  19. 18/32 read-cache: mark new entries for split indexNguyễn Thái Ngọc Duy, Jun 13, 2014
  20. 19/32 read-cache: save deleted entries in split indexNguyễn Thái Ngọc Duy, Jun 13, 2014
  21. 20/32 read-cache: mark updated entries for split indexNguyễn Thái Ngọc Duy, Jun 13, 2014
  22. 21/32 split-index: the writing partNguyễn Thái Ngọc Duy, Jun 13, 2014
  23. 22/32 split-index: the reading partNguyễn Thái Ngọc Duy, Jun 13, 2014
  24. 23/32 split-index: do not invalidate cache-tree at read timeNguyễn Thái Ngọc Duy, Jun 13, 2014
  25. 24/32 split-index: strip pathname of on-disk replaced entriesNguyễn Thái Ngọc Duy, Jun 13, 2014
  26. 25/32 update-index: new options to enable/disable split index modeNguyễn Thái Ngọc Duy, Jun 13, 2014
  27. 26/32 update-index --split-index: do not split if $GIT_DIR is read onlyNguyễn Thái Ngọc Duy, Jun 13, 2014
  28. 27/32 rev-parse: add --shared-index-path to get shared index pathNguyễn Thái Ngọc Duy, Jun 13, 2014
  29. 28/32 read-tree: force split-index mode off on --index-outputNguyễn Thái Ngọc Duy, Jun 13, 2014
  30. 29/32 read-tree: note about dropping split-index mode or index versionNguyễn Thái Ngọc Duy, Jun 13, 2014
  31. 30/32 read-cache: force split index mode with GIT_TEST_SPLIT_INDEXNguyễn Thái Ngọc Duy, Jun 13, 2014
  32. 31/32 t2104: make sure split index mode is off for the version testNguyễn Thái Ngọc Duy, Jun 13, 2014
  33. 32/32 t1700: new tests for split-index modeNguyễn Thái Ngọc Duy, Jun 13, 2014

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