read-cache: clean up casting and byte decoding
This patch does a clean up pass to minimize the casting required to work with the memory mapped index (mmap). It also makes the decoding of network byte order more consistent by using get_be32() where possible. Signed-off-by: Ben Peart <benpeart@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Ben Peart committed
Oct 10, 2018 at 11:59 UTC
371ed0defa2a8692731d164e7a2d5e53e0a22362
1 file changed
+11
-12
read-cache.c
+11
-12
@@ -1650,7 +1650,7 @@ int verify_index_checksum;
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/* Allow fsck to force verification of the cache entry order. */
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int verify_ce_order;
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-static int verify_hdr(struct cache_header *hdr, unsigned long size)
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+static int verify_hdr(const struct cache_header *hdr, unsigned long size)
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{
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git_hash_ctx c;
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unsigned char hash[GIT_MAX_RAWSZ];
@@ -1674,7 +1674,7 @@ static int verify_hdr(struct cache_header *hdr, unsigned long size)
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}
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static int read_index_extension(struct index_state *istate,
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- const char *ext, void *data, unsigned long sz)
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+ const char *ext, const char *data, unsigned long sz)
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{
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switch (CACHE_EXT(ext)) {
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case CACHE_EXT_TREE:
@@ -1889,8 +1889,8 @@ int do_read_index(struct index_state *istate, const char *path, int must_exist)
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int fd, i;
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struct stat st;
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unsigned long src_offset;
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- struct cache_header *hdr;
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- void *mmap;
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+ const struct cache_header *hdr;
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+ const char *mmap;
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size_t mmap_size;
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const struct cache_entry *previous_ce = NULL;
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@@ -1918,7 +1918,7 @@ int do_read_index(struct index_state *istate, const char *path, int must_exist)
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die_errno("unable to map index file");
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close(fd);
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- hdr = mmap;
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+ hdr = (const struct cache_header *)mmap;
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if (verify_hdr(hdr, mmap_size) < 0)
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goto unmap;
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@@ -1943,7 +1943,7 @@ int do_read_index(struct index_state *istate, const char *path, int must_exist)
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struct cache_entry *ce;
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unsigned long consumed;
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- disk_ce = (struct ondisk_cache_entry *)((char *)mmap + src_offset);
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+ disk_ce = (struct ondisk_cache_entry *)(mmap + src_offset);
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ce = create_from_disk(istate, disk_ce, &consumed, previous_ce);
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set_index_entry(istate, i, ce);
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@@ -1961,21 +1961,20 @@ int do_read_index(struct index_state *istate, const char *path, int must_exist)
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* in 4-byte network byte order.
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*/
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uint32_t extsize;
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- memcpy(&extsize, (char *)mmap + src_offset + 4, 4);
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- extsize = ntohl(extsize);
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+ extsize = get_be32(mmap + src_offset + 4);
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if (read_index_extension(istate,
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- (const char *) mmap + src_offset,
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- (char *) mmap + src_offset + 8,
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+ mmap + src_offset,
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+ mmap + src_offset + 8,
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extsize) < 0)
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goto unmap;
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src_offset += 8;
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src_offset += extsize;
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}
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- munmap(mmap, mmap_size);
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+ munmap((void *)mmap, mmap_size);
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return istate->cache_nr;
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unmap:
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- munmap(mmap, mmap_size);
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+ munmap((void *)mmap, mmap_size);
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die("index file corrupt");
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}
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