[PATCH 5/6] Document a bunch of functions defined in sha1_file.c
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
---
cache.h | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++---
sha1_file.c | 26 +++++++++++++-----------
2 files changed, 78 insertions(+), 14 deletions(-)
diff --git a/cache.h b/cache.h
index 1663478..e62fdec 100644
--- a/cache.h
+++ b/cache.h
@@ -659,9 +659,28 @@ extern char *git_path(const char *fmt, ...) __attribute__((format (printf, 1, 2)
extern char *git_path_submodule(const char *path, const char *fmt, ...)
__attribute__((format (printf, 2, 3)));
+/*
+ * Return the name of the file in the local object database that would
+ * be used to store a loose object with the specified sha1. The
+ * return value is a pointer to a statically allocated buffer that is
+ * overwritten each time the function is called.
+ */
extern const char *sha1_file_name(const unsigned char *sha1);
+
+/*
+ * Return the name of the (local) packfile with the specified sha1 in
+ * its name. The return value is a pointer to memory that is
+ * overwritten each time this function is called.
+ */
extern char *sha1_pack_name(const unsigned char *sha1);
+
+/*
+ * Return the name of the (local) pack index file with the specified
+ * sha1 in its name. The return value is a pointer to memory that is
+ * overwritten each time this function is called.
+ */
extern char *sha1_pack_index_name(const unsigned char *sha1);
+
extern const char *find_unique_abbrev(const unsigned char *sha1, int);
extern const unsigned char null_sha1[20];
@@ -836,7 +855,19 @@ extern int check_sha1_signature(const unsigned char *sha1, void *buf, unsigned l
extern int move_temp_to_file(const char *tmpfile, const char *filename);
extern int has_sha1_pack(const unsigned char *sha1);
+
+/*
+ * Return true iff we have an object named sha1, whether local or in
+ * an alternate object database, and whether packed or loose. This
+ * function does not respect replace references.
+ */
extern int has_sha1_file(const unsigned char *sha1);
+
+/*
+ * Return true iff an alternate object database has a loose object
+ * with the specified name. This function does not respect replace
+ * references.
+ */
extern int has_loose_object_nonlocal(const unsigned char *sha1);
extern int has_pack_index(const unsigned char *sha1);
@@ -1099,17 +1130,46 @@ extern struct packed_git *find_sha1_pack(const unsigned char *sha1,
struct packed_git *packs);
extern void pack_report(void);
+
+/*
+ * mmap the index file for the specified packfile (if it is not
+ * already mmapped). Return 0 on success.
+ */
extern int open_pack_index(struct packed_git *);
+
+/*
+ * munmap the index file for the specified packfile (if it is
+ * currently mmapped).
+ */
extern void close_pack_index(struct packed_git *);
+
extern unsigned char *use_pack(struct packed_git *, struct pack_window **, off_t, unsigned long *);
extern void close_pack_windows(struct packed_git *);
extern void unuse_pack(struct pack_window **);
extern void free_pack_by_name(const char *);
extern void clear_delta_base_cache(void);
extern struct packed_git *add_packed_git(const char *, int, int);
-extern const unsigned char *nth_packed_object_sha1(struct packed_git *, uint32_t);
-extern off_t nth_packed_object_offset(const struct packed_git *, uint32_t);
-extern off_t find_pack_entry_one(const unsigned char *, struct packed_git *);
+
+/*
+ * Return the SHA-1 of the nth object within the specified packfile.
+ * Open the index if it is not already open. The return value points
+ * at the SHA-1 within the mmapped index. Return NULL if there is an
+ * error.
+ */
+extern const unsigned char *nth_packed_object_sha1(struct packed_git *, uint32_t n);
+
+/*
+ * Return the offset of the nth object within the specified packfile.
+ * The index must already be opened.
+ */
+extern off_t nth_packed_object_offset(const struct packed_git *, uint32_t n);
+
+/*
+ * If the object named sha1 is present in the specified packfile,
+ * return its offset within the packfile; otherwise, return 0.
+ */
+extern off_t find_pack_entry_one(const unsigned char *sha1, struct packed_git *);
+
extern int is_pack_valid(struct packed_git *);
extern void *unpack_entry(struct packed_git *, off_t, enum object_type *, unsigned long *);
extern unsigned long unpack_object_header_buffer(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
diff --git a/sha1_file.c b/sha1_file.c
index ba62804..bb9f097 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -184,16 +184,6 @@ static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
}
}
-/*
- * NOTE! This returns a statically allocated buffer, so you have to be
- * careful about using it. Do an "xstrdup()" if you need to save the
- * filename.
- *
- * Also note that this returns the location for creating. Reading
- * SHA1 file can happen from any alternate directory listed in the
- * DB_ENVIRONMENT environment variable if it is not found in
- * the primary object database.
- */
const char *sha1_file_name(const unsigned char *sha1)
{
static char buf[PATH_MAX];
@@ -214,6 +204,11 @@ const char *sha1_file_name(const unsigned char *sha1)
return buf;
}
+/*
+ * Return the name of the pack or index file with the specified sha1
+ * in its filename. *base and *name are scratch space that must be
+ * provided by the caller. which should be "pack" or "idx".
+ */
static char *sha1_get_pack_name(const unsigned char *sha1,
char **name, char **base, const char *which)
{
@@ -496,7 +491,12 @@ void pack_report(void)
sz_fmt(pack_mapped), sz_fmt(peak_pack_mapped));
}
-static int check_packed_git_idx(const char *path, struct packed_git *p)
+/*
+ * Open and mmap the index file at path, perform a couple of
+ * consistency checks, then record its information to p. Return 0 on
+ * success.
+ */
+static int check_packed_git_idx(const char *path, struct packed_git *p)
{
void *idx_map;
struct pack_idx_header *hdr;
@@ -2449,6 +2449,10 @@ static int fill_pack_entry(const unsigned char *sha1,
return 1;
}
+/*
+ * Iff a pack file contains the object named by sha1, return true and
+ * store its location to e.
+ */
static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e)
{
struct packed_git *p;
--
1.8.5.3
Michael Haggerty <mhagger@alum.mit.edu>