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 <Ben.Peart@xxxxxxxxxxxxx> --- read-cache.c | 49 +++++++++++++++++++++++-------------------------- 1 file changed, 23 insertions(+), 26 deletions(-) diff --git a/read-cache.c b/read-cache.c index d21ccb5e67..6220abc491 100644 --- a/read-cache.c +++ b/read-cache.c @@ -1655,7 +1655,7 @@ int verify_index_checksum; /* Allow fsck to force verification of the cache entry order. */ int verify_ce_order; -static int verify_hdr(struct cache_header *hdr, unsigned long size) +static int verify_hdr(const struct cache_header *hdr, unsigned long size) { git_hash_ctx c; unsigned char hash[GIT_MAX_RAWSZ]; @@ -1679,7 +1679,7 @@ static int verify_hdr(struct cache_header *hdr, unsigned long size) } static int read_index_extension(struct index_state *istate, - const char *ext, void *data, unsigned long sz) + const char *ext, const char *data, unsigned long sz) { switch (CACHE_EXT(ext)) { case CACHE_EXT_TREE: @@ -1906,7 +1906,7 @@ static size_t estimate_cache_size(size_t ondisk_size, unsigned int entries) } #ifndef NO_PTHREADS -static unsigned long read_eoie_extension(void *mmap_, size_t mmap_size); +static unsigned long read_eoie_extension(const char *mmap, size_t mmap_size); #endif static void write_eoie_extension(struct strbuf *sb, git_hash_ctx *eoie_context, unsigned long offset); @@ -1916,14 +1916,14 @@ struct load_index_extensions pthread_t pthread; #endif struct index_state *istate; - void *mmap; + const char *mmap; size_t mmap_size; unsigned long src_offset; }; -static void *load_index_extensions(void *_data) +static void *load_index_extensions(void *data) { - struct load_index_extensions *p = _data; + struct load_index_extensions *p = data; unsigned long src_offset = p->src_offset; while (src_offset <= p->mmap_size - the_hash_algo->rawsz - 8) { @@ -1934,13 +1934,12 @@ static void *load_index_extensions(void *_data) * in 4-byte network byte order. */ uint32_t extsize; - memcpy(&extsize, (char *)p->mmap + src_offset + 4, 4); - extsize = ntohl(extsize); + extsize = get_be32(p->mmap + src_offset + 4); if (read_index_extension(p->istate, - (const char *)p->mmap + src_offset, - (char *)p->mmap + src_offset + 8, + p->mmap + src_offset, + p->mmap + src_offset + 8, extsize) < 0) { - munmap(p->mmap, p->mmap_size); + munmap((void *)p->mmap, p->mmap_size); die("index file corrupt"); } src_offset += 8; @@ -1955,7 +1954,7 @@ static void *load_index_extensions(void *_data) * from the memory mapped file and add them to the given index. */ static unsigned long load_cache_entry_block(struct index_state *istate, - struct mem_pool *ce_mem_pool, int offset, int nr, void *mmap, + struct mem_pool *ce_mem_pool, int offset, int nr, const char *mmap, unsigned long start_offset, const struct cache_entry *previous_ce) { int i; @@ -1966,7 +1965,7 @@ static unsigned long load_cache_entry_block(struct index_state *istate, struct cache_entry *ce; unsigned long consumed; - disk_ce = (struct ondisk_cache_entry *)((char *)mmap + src_offset); + disk_ce = (struct ondisk_cache_entry *)(mmap + src_offset); ce = create_from_disk(ce_mem_pool, istate->version, disk_ce, &consumed, previous_ce); set_index_entry(istate, i, ce); @@ -1977,7 +1976,7 @@ static unsigned long load_cache_entry_block(struct index_state *istate, } static unsigned long load_all_cache_entries(struct index_state *istate, - void *mmap, size_t mmap_size, unsigned long src_offset) + const char *mmap, size_t mmap_size, unsigned long src_offset) { unsigned long consumed; @@ -2008,7 +2007,7 @@ struct load_cache_entries_thread_data struct index_state *istate; struct mem_pool *ce_mem_pool; int offset, nr; - void *mmap; + const char *mmap; unsigned long start_offset; struct cache_entry *previous_ce; unsigned long consumed; /* return # of bytes in index file processed */ @@ -2028,7 +2027,7 @@ static void *load_cache_entries_thread(void *_data) } static unsigned long load_cache_entries_threaded(int nr_threads, struct index_state *istate, - void *mmap, size_t mmap_size, unsigned long src_offset) + const char *mmap, size_t mmap_size, unsigned long src_offset) { struct strbuf previous_name_buf = STRBUF_INIT, *previous_name; struct load_cache_entries_thread_data *data; @@ -2097,7 +2096,7 @@ static unsigned long load_cache_entries_threaded(int nr_threads, struct index_st break; } - ondisk = (struct ondisk_cache_entry *)((char *)mmap + src_offset); + ondisk = (struct ondisk_cache_entry *)(mmap + src_offset); /* On-disk flags are just 16 bits */ flags = get_be16(&ondisk->flags); @@ -2145,8 +2144,8 @@ int do_read_index(struct index_state *istate, const char *path, int must_exist) int fd; struct stat st; unsigned long src_offset; - struct cache_header *hdr; - void *mmap; + const struct cache_header *hdr; + const char *mmap; size_t mmap_size; struct load_index_extensions p = { 0 }; unsigned long extension_offset = 0; @@ -2178,7 +2177,7 @@ int do_read_index(struct index_state *istate, const char *path, int must_exist) die_errno("unable to map index file"); close(fd); - hdr = mmap; + hdr = (const struct cache_header *)mmap; if (verify_hdr(hdr, mmap_size) < 0) goto unmap; @@ -2238,11 +2237,11 @@ int do_read_index(struct index_state *istate, const char *path, int must_exist) p.src_offset = src_offset; load_index_extensions(&p); } - munmap(mmap, mmap_size); + munmap((void *)mmap, mmap_size); return istate->cache_nr; unmap: - munmap(mmap, mmap_size); + munmap((void *)mmap, mmap_size); die("index file corrupt"); } @@ -3265,7 +3264,7 @@ int should_validate_cache_entries(void) #define EOIE_SIZE_WITH_HEADER (4 + 4 + EOIE_SIZE) /* <4-byte signature> + <4-byte length> + EOIE_SIZE */ #ifndef NO_PTHREADS -static unsigned long read_eoie_extension(void *mmap_, size_t mmap_size) +static unsigned long read_eoie_extension(const char *mmap, size_t mmap_size) { /* * The end of index entries (EOIE) extension is guaranteed to be last @@ -3276,7 +3275,6 @@ static unsigned long read_eoie_extension(void *mmap_, size_t mmap_size) * <4-byte offset> * <20-byte hash> */ - const char *mmap = mmap_; const char *index, *eoie; uint32_t extsize; unsigned long offset, src_offset; @@ -3329,8 +3327,7 @@ static unsigned long read_eoie_extension(void *mmap_, size_t mmap_size) * in 4-byte network byte order. */ uint32_t extsize; - memcpy(&extsize, (char *)mmap + src_offset + 4, 4); - extsize = ntohl(extsize); + extsize = get_be32(mmap + src_offset + 4); /* verify the extension size isn't so large it will wrap around */ if (src_offset + 8 + extsize < src_offset) -- 2.18.0.windows.1