fast-import: use write_idx_file() instead of custom code

This allows for the creation of pack index version 2 with its object
CRC and the possibility for a pack to be larger than 4 GB.

Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

fast-import.c

@@ -854,67 +854,30 @@ static void start_packfile(void)
 	all_packs[pack_id] = p;
 }
 
-static int oecmp (const void *a_, const void *b_)
+static const char *create_index(void)
 {
-	struct object_entry *a = *((struct object_entry**)a_);
-	struct object_entry *b = *((struct object_entry**)b_);
-	return hashcmp(a->idx.sha1, b->idx.sha1);
-}
-
-static char *create_index(void)
-{
-	static char tmpfile[PATH_MAX];
-	git_SHA_CTX ctx;
-	struct sha1file *f;
-	struct object_entry **idx, **c, **last, *e;
+	const char *tmpfile;
+	struct pack_idx_entry **idx, **c, **last;
+	struct object_entry *e;
 	struct object_entry_pool *o;
-	uint32_t array[256];
-	int i, idx_fd;
 
-	/* Build the sorted table of object IDs. */
-	idx = xmalloc(object_count * sizeof(struct object_entry*));
+	/* Build the table of object IDs. */
+	idx = xmalloc(object_count * sizeof(*idx));
 	c = idx;
 	for (o = blocks; o; o = o->next_pool)
 		for (e = o->next_free; e-- != o->entries;)
 			if (pack_id == e->pack_id)
-				*c++ = e;
+				*c++ = &e->idx;
 	last = idx + object_count;
 	if (c != last)
 		die("internal consistency error creating the index");
-	qsort(idx, object_count, sizeof(struct object_entry*), oecmp);
 
-	/* Generate the fan-out array. */
-	c = idx;
-	for (i = 0; i < 256; i++) {
-		struct object_entry **next = c;
-		while (next < last) {
-			if ((*next)->idx.sha1[0] != i)
-				break;
-			next++;
-		}
-		array[i] = htonl(next - idx);
-		c = next;
-	}
-
-	idx_fd = odb_mkstemp(tmpfile, sizeof(tmpfile),
-			     "pack/tmp_idx_XXXXXX");
-	f = sha1fd(idx_fd, tmpfile);
-	sha1write(f, array, 256 * sizeof(int));
-	git_SHA1_Init(&ctx);
-	for (c = idx; c != last; c++) {
-		uint32_t offset = htonl((*c)->idx.offset);
-		sha1write(f, &offset, 4);
-		sha1write(f, (*c)->idx.sha1, sizeof((*c)->idx.sha1));
-		git_SHA1_Update(&ctx, (*c)->idx.sha1, 20);
-	}
-	sha1write(f, pack_data->sha1, sizeof(pack_data->sha1));
-	sha1close(f, NULL, CSUM_FSYNC);
+	tmpfile = write_idx_file(NULL, idx, object_count, pack_data->sha1);
 	free(idx);
-	git_SHA1_Final(pack_data->sha1, &ctx);
 	return tmpfile;
 }
 
-static char *keep_pack(char *curr_index_name)
+static char *keep_pack(const char *curr_index_name)
 {
 	static char name[PATH_MAX];
 	static const char *keep_msg = "fast-import";
@@ -936,6 +899,7 @@ static char *keep_pack(char *curr_index_name)
 		 get_object_directory(), sha1_to_hex(pack_data->sha1));
 	if (move_temp_to_file(curr_index_name, name))
 		die("cannot store index file");
+	free((void *)curr_index_name);
 	return name;
 }
 
@@ -1134,6 +1098,8 @@ static int store_object(
 	object_count++;
 	object_count_by_type[type]++;
 
+	crc32_begin(pack_file);
+
 	if (delta) {
 		unsigned long ofs = e->idx.offset - last->offset;
 		unsigned pos = sizeof(hdr) - 1;
@@ -1160,6 +1126,8 @@ static int store_object(
 	sha1write(pack_file, out, s.total_out);
 	pack_size += s.total_out;
 
+	e->idx.crc32 = crc32_end(pack_file);
+
 	free(out);
 	free(delta);
 	if (last) {
@@ -1219,6 +1187,8 @@ static void stream_blob(uintmax_t len, unsigned char *sha1out, uintmax_t mark)
 	git_SHA1_Init(&c);
 	git_SHA1_Update(&c, out_buf, hdrlen);
 
+	crc32_begin(pack_file);
+
 	memset(&s, 0, sizeof(s));
 	deflateInit(&s, pack_compression_level);
 
@@ -1288,6 +1258,7 @@ static void stream_blob(uintmax_t len, unsigned char *sha1out, uintmax_t mark)
 		e->type = OBJ_BLOB;
 		e->pack_id = pack_id;
 		e->idx.offset = offset;
+		e->idx.crc32 = crc32_end(pack_file);
 		object_count++;
 		object_count_by_type[OBJ_BLOB]++;
 	}