pack: move check_pack_index_ptr(), nth_packed_object_offset()

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

Author: jonathantanmy

cache.h

@@ -1620,22 +1620,6 @@ extern int odb_mkstemp(struct strbuf *template, const char *pattern);
  */
 extern int odb_pack_keep(const char *name);
 
-/*
- * Make sure that a pointer access into an mmap'd index file is within bounds,
- * and can provide at least 8 bytes of data.
- *
- * Note that this is only necessary for variable-length segments of the file
- * (like the 64-bit extended offset table), as we compare the size to the
- * fixed-length parts when we open the file.
- */
-extern void check_pack_index_ptr(const struct packed_git *p, const void *ptr);
-
-/*
- * 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.

packfile.c

@@ -1667,3 +1667,36 @@ const struct object_id *nth_packed_object_oid(struct object_id *oid,
 	hashcpy(oid->hash, hash);
 	return oid;
 }
+
+void check_pack_index_ptr(const struct packed_git *p, const void *vptr)
+{
+	const unsigned char *ptr = vptr;
+	const unsigned char *start = p->index_data;
+	const unsigned char *end = start + p->index_size;
+	if (ptr < start)
+		die(_("offset before start of pack index for %s (corrupt index?)"),
+		    p->pack_name);
+	/* No need to check for underflow; .idx files must be at least 8 bytes */
+	if (ptr >= end - 8)
+		die(_("offset beyond end of pack index for %s (truncated index?)"),
+		    p->pack_name);
+}
+
+off_t nth_packed_object_offset(const struct packed_git *p, uint32_t n)
+{
+	const unsigned char *index = p->index_data;
+	index += 4 * 256;
+	if (p->index_version == 1) {
+		return ntohl(*((uint32_t *)(index + 24 * n)));
+	} else {
+		uint32_t off;
+		index += 8 + p->num_objects * (20 + 4);
+		off = ntohl(*((uint32_t *)(index + 4 * n)));
+		if (!(off & 0x80000000))
+			return off;
+		index += p->num_objects * 4 + (off & 0x7fffffff) * 8;
+		check_pack_index_ptr(p, index);
+		return (((uint64_t)ntohl(*((uint32_t *)(index + 0)))) << 32) |
+				   ntohl(*((uint32_t *)(index + 4)));
+	}
+}

packfile.h

@@ -63,6 +63,16 @@ extern void unuse_pack(struct pack_window **);
 extern void clear_delta_base_cache(void);
 extern struct packed_git *add_packed_git(const char *path, size_t path_len, int local);
 
+/*
+ * Make sure that a pointer access into an mmap'd index file is within bounds,
+ * and can provide at least 8 bytes of data.
+ *
+ * Note that this is only necessary for variable-length segments of the file
+ * (like the 64-bit extended offset table), as we compare the size to the
+ * fixed-length parts when we open the file.
+ */
+extern void check_pack_index_ptr(const struct packed_git *p, const void *ptr);
+
 /*
  * 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
@@ -77,6 +87,11 @@ extern const unsigned char *nth_packed_object_sha1(struct packed_git *, uint32_t
  */
 extern const struct object_id *nth_packed_object_oid(struct object_id *, 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);
 
 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);
@@ -94,4 +109,5 @@ extern int packed_object_info(struct packed_git *pack, off_t offset, struct obje
 
 extern void mark_bad_packed_object(struct packed_git *p, const unsigned char *sha1);
 extern const struct packed_git *has_packed_and_bad(const unsigned char *sha1);
+
 #endif

sha1_file.c

@@ -1075,39 +1075,6 @@ int parse_sha1_header(const char *hdr, unsigned long *sizep)
 	return parse_sha1_header_extended(hdr, &oi, 0);
 }
 
-void check_pack_index_ptr(const struct packed_git *p, const void *vptr)
-{
-	const unsigned char *ptr = vptr;
-	const unsigned char *start = p->index_data;
-	const unsigned char *end = start + p->index_size;
-	if (ptr < start)
-		die(_("offset before start of pack index for %s (corrupt index?)"),
-		    p->pack_name);
-	/* No need to check for underflow; .idx files must be at least 8 bytes */
-	if (ptr >= end - 8)
-		die(_("offset beyond end of pack index for %s (truncated index?)"),
-		    p->pack_name);
-}
-
-off_t nth_packed_object_offset(const struct packed_git *p, uint32_t n)
-{
-	const unsigned char *index = p->index_data;
-	index += 4 * 256;
-	if (p->index_version == 1) {
-		return ntohl(*((uint32_t *)(index + 24 * n)));
-	} else {
-		uint32_t off;
-		index += 8 + p->num_objects * (20 + 4);
-		off = ntohl(*((uint32_t *)(index + 4 * n)));
-		if (!(off & 0x80000000))
-			return off;
-		index += p->num_objects * 4 + (off & 0x7fffffff) * 8;
-		check_pack_index_ptr(p, index);
-		return (((uint64_t)ntohl(*((uint32_t *)(index + 0)))) << 32) |
-				   ntohl(*((uint32_t *)(index + 4)));
-	}
-}
-
 off_t find_pack_entry_one(const unsigned char *sha1,
 				  struct packed_git *p)
 {