From 7f0fa2c02a6543bdadae3c4a492daae7dbc8c042 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Mon, 3 Oct 2016 16:35:31 -0400 Subject: [PATCH] alternates: provide helper for allocating alternate Allocating a struct alternate_object_database is tricky, as we must over-allocate the buffer to provide scratch space, and then put in particular '/' and NUL markers. Let's encapsulate this in a function so that the complexity doesn't leak into callers (and so that we can modify it later). Signed-off-by: Jeff King Signed-off-by: Junio C Hamano --- cache.h | 6 ++++++ sha1_file.c | 28 +++++++++++++++++++--------- sha1_name.c | 7 +------ 3 files changed, 26 insertions(+), 15 deletions(-) diff --git a/cache.h b/cache.h index 258ce6b0f0..ece2c7c9b8 100644 --- a/cache.h +++ b/cache.h @@ -1392,6 +1392,12 @@ extern char *compute_alternate_path(const char *path, struct strbuf *err); typedef int alt_odb_fn(struct alternate_object_database *, void *); extern int foreach_alt_odb(alt_odb_fn, void*); +/* + * Allocate a "struct alternate_object_database" but do _not_ actually + * add it to the list of alternates. + */ +struct alternate_object_database *alloc_alt_odb(const char *dir); + /* * Add the directory to the on-disk alternates file; the new entry will also * take effect in the current process. diff --git a/sha1_file.c b/sha1_file.c index 7a3b745448..636d07ad14 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -283,7 +283,6 @@ static int link_alt_odb_entry(const char *entry, const char *relative_base, int depth, const char *normalized_objdir) { struct alternate_object_database *ent; - size_t entlen; struct strbuf pathbuf = STRBUF_INIT; if (!is_absolute_path(entry) && relative_base) { @@ -311,14 +310,7 @@ static int link_alt_odb_entry(const char *entry, const char *relative_base, return -1; } - entlen = st_add(pathbuf.len, 43); /* '/' + 2 hex + '/' + 38 hex + NUL */ - ent = xmalloc(st_add(sizeof(*ent), entlen)); - memcpy(ent->base, pathbuf.buf, pathbuf.len); - - ent->name = ent->base + pathbuf.len + 1; - ent->base[pathbuf.len] = '/'; - ent->base[pathbuf.len + 3] = '/'; - ent->base[entlen-1] = 0; + ent = alloc_alt_odb(pathbuf.buf); /* add the alternate entry */ *alt_odb_tail = ent; @@ -395,6 +387,24 @@ void read_info_alternates(const char * relative_base, int depth) munmap(map, mapsz); } +struct alternate_object_database *alloc_alt_odb(const char *dir) +{ + struct alternate_object_database *ent; + size_t dirlen = strlen(dir); + size_t entlen; + + entlen = st_add(dirlen, 43); /* '/' + 2 hex + '/' + 38 hex + NUL */ + ent = xmalloc(st_add(sizeof(*ent), entlen)); + memcpy(ent->base, dir, dirlen); + + ent->name = ent->base + dirlen + 1; + ent->base[dirlen] = '/'; + ent->base[dirlen + 3] = '/'; + ent->base[entlen-1] = 0; + + return ent; +} + void add_to_alternates_file(const char *reference) { struct lock_file *lock = xcalloc(1, sizeof(struct lock_file)); diff --git a/sha1_name.c b/sha1_name.c index faf873cf7f..98152a68ba 100644 --- a/sha1_name.c +++ b/sha1_name.c @@ -86,12 +86,7 @@ static void find_short_object_filename(int len, const char *hex_pfx, struct disa * alt->name/alt->base while iterating over the * object databases including our own. */ - const char *objdir = get_object_directory(); - size_t objdir_len = strlen(objdir); - fakeent = xmalloc(st_add3(sizeof(*fakeent), objdir_len, 43)); - memcpy(fakeent->base, objdir, objdir_len); - fakeent->name = fakeent->base + objdir_len + 1; - fakeent->name[-1] = '/'; + fakeent = alloc_alt_odb(get_object_directory()); } fakeent->next = alt_odb_list;