[PATCH v6 08/40] sha1_file: prepare for external odbs

From

Christian Couder <christian.couder@gmail.com>

Date

Sep 16, 2017, 08:06 UTC

Message-ID

<20170916080731.13925-9-chriscool@tuxfamily.org>

In-Reply-To

<20170916080731.13925-1-chriscool@tuxfamily.org>

Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
---
 cache.h     |  8 ++++++++
 sha1_file.c | 47 +++++++++++++++++++++++++++++------------------
 2 files changed, 37 insertions(+), 18 deletions(-)

diff --git a/cache.h b/cache.h
index a916bc79e3..00d89568f3 100644
--- a/cache.h
+++ b/cache.h
@@ -902,6 +902,12 @@ extern void check_repository_format(void);
  */
 extern const char *sha1_file_name(const unsigned char *sha1);
 
+/*
+ * Like sha1_file_name, but return the filename within a specific alternate
+ * object directory. Shares the same static buffer with sha1_file_name.
+ */
+extern const char *sha1_file_name_alt(const char *objdir, const unsigned char *sha1);
+
 /*
  * Return an abbreviated sha1 unique within this repository's object database.
  * The result will be at least `len` characters long, and will be NUL
@@ -1189,6 +1195,8 @@ extern int parse_sha1_header(const char *hdr, unsigned long *sizep);
 
 extern int check_sha1_signature(const unsigned char *sha1, void *buf, unsigned long size, const char *type);
 
+extern int create_object_tmpfile(struct strbuf *tmp, const char *filename);
+extern void close_sha1_file(int fd);
 extern int finalize_object_file(const char *tmpfile, const char *filename);
 
 /*
diff --git a/sha1_file.c b/sha1_file.c
index 5f71bbac3e..bea1ae6afb 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -251,17 +251,22 @@ static void fill_sha1_path(struct strbuf *buf, const unsigned char *sha1)
 	}
 }
 
-const char *sha1_file_name(const unsigned char *sha1)
+const char *sha1_file_name_alt(const char *objdir, const unsigned char *sha1)
 {
 	static struct strbuf buf = STRBUF_INIT;
 
 	strbuf_reset(&buf);
-	strbuf_addf(&buf, "%s/", get_object_directory());
+	strbuf_addf(&buf, "%s/", objdir);
 
 	fill_sha1_path(&buf, sha1);
 	return buf.buf;
 }
 
+const char *sha1_file_name(const unsigned char *sha1)
+{
+	return sha1_file_name_alt(get_object_directory(), sha1);
+}
+
 struct strbuf *alt_scratch_buf(struct alternate_object_database *alt)
 {
 	strbuf_setlen(&alt->scratch, alt->base_len);
@@ -822,24 +827,14 @@ static int stat_sha1_file(const unsigned char *sha1, struct stat *st,
 	return -1;
 }
 
-/*
- * Like stat_sha1_file(), but actually open the object and return the
- * descriptor. See the caveats on the "path" parameter above.
- */
-static int open_sha1_file(const unsigned char *sha1, const char **path)
+static int open_sha1_file_alt(const unsigned char *sha1, const char **path)
 {
-	int fd;
 	struct alternate_object_database *alt;
-	int most_interesting_errno;
-
-	*path = sha1_file_name(sha1);
-	fd = git_open(*path);
-	if (fd >= 0)
-		return fd;
-	most_interesting_errno = errno;
+	int most_interesting_errno = errno;
 
 	prepare_alt_odb();
 	for (alt = alt_odb_list; alt; alt = alt->next) {
+		int fd;
 		*path = alt_sha1_path(alt, sha1);
 		fd = git_open(*path);
 		if (fd >= 0)
@@ -851,6 +846,22 @@ static int open_sha1_file(const unsigned char *sha1, const char **path)
 	return -1;
 }
 
+/*
+ * Like stat_sha1_file(), but actually open the object and return the
+ * descriptor. See the caveats on the "path" parameter above.
+ */
+static int open_sha1_file(const unsigned char *sha1, const char **path)
+{
+	int fd;
+
+	*path = sha1_file_name(sha1);
+	fd = git_open(*path);
+	if (fd >= 0)
+		return fd;
+
+	return open_sha1_file_alt(sha1, path);
+}
+
 /*
  * Map the loose object at "path" if it is not NULL, or the path found by
  * searching for a loose object named "sha1".
@@ -1428,7 +1439,7 @@ int hash_sha1_file(const void *buf, unsigned long len, const char *type,
 }
 
 /* Finalize a file on disk, and close it. */
-static void close_sha1_file(int fd)
+void close_sha1_file(int fd)
 {
 	if (fsync_object_files)
 		fsync_or_die(fd, "sha1 file");
@@ -1452,7 +1463,7 @@ static inline int directory_size(const char *filename)
  * We want to avoid cross-directory filename renames, because those
  * can have problems on various filesystems (FAT, NFS, Coda).
  */
-static int create_tmpfile(struct strbuf *tmp, const char *filename)
+int create_object_tmpfile(struct strbuf *tmp, const char *filename)
 {
 	int fd, dirlen = directory_size(filename);
 
@@ -1492,7 +1503,7 @@ static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen,
 	static struct strbuf tmp_file = STRBUF_INIT;
 	const char *filename = sha1_file_name(sha1);
 
-	fd = create_tmpfile(&tmp_file, filename);
+	fd = create_object_tmpfile(&tmp_file, filename);
 	if (fd < 0) {
 		if (errno == EACCES)
 			return error("insufficient permission for adding an object to repository database %s", get_object_directory());

-- 
2.14.1.576.g3f707d88cd