pack: move pack name-related functions

Currently, sha1_file.c and cache.h contain many functions, both related
to and unrelated to packfiles. This makes both files very large and
causes an unclear separation of concerns.

Create a new file, packfile.c, to hold all packfile-related functions
currently in sha1_file.c. It has a corresponding header packfile.h.

In this commit, the pack name-related functions are moved. Subsequent
commits will move the other functions.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Makefile

@@ -816,6 +816,7 @@ LIB_OBJS += notes-merge.o
 LIB_OBJS += notes-utils.o
 LIB_OBJS += object.o
 LIB_OBJS += oidset.o
+LIB_OBJS += packfile.o
 LIB_OBJS += pack-bitmap.o
 LIB_OBJS += pack-bitmap-write.o
 LIB_OBJS += pack-check.o

builtin/index-pack.c

@@ -12,6 +12,7 @@
 #include "exec_cmd.h"
 #include "streaming.h"
 #include "thread-utils.h"
+#include "packfile.h"
 
 static const char index_pack_usage[] =
 "git index-pack [-v] [-o <index-file>] [--keep | --keep=<msg>] [--verify] [--strict] (<pack-file> | --stdin [--fix-thin] [<pack-file>])";

builtin/pack-redundant.c

@@ -7,6 +7,7 @@
 */
 
 #include "builtin.h"
+#include "packfile.h"
 
 #define BLKSIZE 512
 

cache.h

@@ -902,20 +902,6 @@ extern void check_repository_format(void);
  */
 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);
-
 /*
  * Return an abbreviated sha1 unique within this repository's object database.
  * The result will be at least `len` characters long, and will be NUL
@@ -1650,15 +1636,6 @@ extern void pack_report(void);
  */
 extern int odb_mkstemp(struct strbuf *template, const char *pattern);
 
-/*
- * Generate the filename to be used for a pack file with checksum "sha1" and
- * extension "ext". The result is written into the strbuf "buf", overwriting
- * any existing contents. A pointer to buf->buf is returned as a convenience.
- *
- * Example: odb_pack_name(out, sha1, "idx") => ".git/objects/pack/pack-1234..idx"
- */
-extern char *odb_pack_name(struct strbuf *buf, const unsigned char *sha1, const char *ext);
-
 /*
  * Create a pack .keep file named "name" (which should generally be the output
  * of odb_pack_name). Returns a file descriptor opened for writing, or -1 on

fast-import.c

@@ -167,6 +167,7 @@ Format of STDIN stream:
 #include "quote.h"
 #include "dir.h"
 #include "run-command.h"
+#include "packfile.h"
 
 #define PACK_ID_BITS 16
 #define MAX_PACK_ID ((1<<PACK_ID_BITS)-1)

http.c

@@ -11,6 +11,7 @@
 #include "pkt-line.h"
 #include "gettext.h"
 #include "transport.h"
+#include "packfile.h"
 
 static struct trace_key trace_curl = TRACE_KEY_INIT(CURL);
 #if LIBCURL_VERSION_NUM >= 0x070a08

packfile.c

@@ -0,0 +1,23 @@
+#include "cache.h"
+
+char *odb_pack_name(struct strbuf *buf,
+		    const unsigned char *sha1,
+		    const char *ext)
+{
+	strbuf_reset(buf);
+	strbuf_addf(buf, "%s/pack/pack-%s.%s", get_object_directory(),
+		    sha1_to_hex(sha1), ext);
+	return buf->buf;
+}
+
+char *sha1_pack_name(const unsigned char *sha1)
+{
+	static struct strbuf buf = STRBUF_INIT;
+	return odb_pack_name(&buf, sha1, "pack");
+}
+
+char *sha1_pack_index_name(const unsigned char *sha1)
+{
+	static struct strbuf buf = STRBUF_INIT;
+	return odb_pack_name(&buf, sha1, "idx");
+}

packfile.h

@@ -0,0 +1,27 @@
+#ifndef PACKFILE_H
+#define PACKFILE_H
+
+/*
+ * Generate the filename to be used for a pack file with checksum "sha1" and
+ * extension "ext". The result is written into the strbuf "buf", overwriting
+ * any existing contents. A pointer to buf->buf is returned as a convenience.
+ *
+ * Example: odb_pack_name(out, sha1, "idx") => ".git/objects/pack/pack-1234..idx"
+ */
+extern char *odb_pack_name(struct strbuf *buf, const unsigned char *sha1, const char *ext);
+
+/*
+ * 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);
+
+#endif

sha1_file.c

@@ -28,6 +28,7 @@
 #include "list.h"
 #include "mergesort.h"
 #include "quote.h"
+#include "packfile.h"
 
 #define SZ_FMT PRIuMAX
 static inline uintmax_t sz_fmt(size_t s) { return s; }
@@ -278,28 +279,6 @@ static const char *alt_sha1_path(struct alternate_object_database *alt,
 	return buf->buf;
 }
 
- char *odb_pack_name(struct strbuf *buf,
-		     const unsigned char *sha1,
-		     const char *ext)
-{
-	strbuf_reset(buf);
-	strbuf_addf(buf, "%s/pack/pack-%s.%s", get_object_directory(),
-		    sha1_to_hex(sha1), ext);
-	return buf->buf;
-}
-
-char *sha1_pack_name(const unsigned char *sha1)
-{
-	static struct strbuf buf = STRBUF_INIT;
-	return odb_pack_name(&buf, sha1, "pack");
-}
-
-char *sha1_pack_index_name(const unsigned char *sha1)
-{
-	static struct strbuf buf = STRBUF_INIT;
-	return odb_pack_name(&buf, sha1, "idx");
-}
-
 struct alternate_object_database *alt_odb_list;
 static struct alternate_object_database **alt_odb_tail;