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[PATCH 4/6] formalize typename(), and add its reverse type_from_string()

From
Nicolas Pitre <nico@cam.org>
Date
Feb 26, 2007, 19:55 UTC
Message-ID
<11725197633144-git-send-email-nico@cam.org>
In-Reply-To
<11725197622423-git-send-email-nico@cam.org>

Sometime typename() is used, sometimes type_names[] is accessed directly. Let's enforce typename() all the time which allows for validating the type.

Also let's add a function to go from a name to a type and use it instead of manual memcpy() when appropriate.

Signed-off-by: Nicolas Pitre <nico@cam.org>
---
 builtin-for-each-ref.c |    2 +-
 builtin-pack-objects.c |   13 +------------
 fast-import.c          |   10 +++++-----
 index-pack.c           |    7 +------
 object.c               |   26 +++++++++++++++++++++++---
 object.h               |   10 +++-------
 sha1_file.c            |   19 +++++--------------
 7 files changed, 39 insertions(+), 48 deletions(-)
diff --git a/builtin-for-each-ref.c b/builtin-for-each-ref.c
index ac0b9f6..14fff2b 100644
--- a/builtin-for-each-ref.c
+++ b/builtin-for-each-ref.c
@@ -196,7 +196,7 @@ static void grab_common_values(struct atom_value *val, int deref, struct object
 		if (deref)
 			name++;
 		if (!strcmp(name, "objecttype"))
-			v->s = type_names[obj->type];
+			v->s = typename(obj->type);
 		else if (!strcmp(name, "objectsize")) {
 			char *s = xmalloc(40);
 			sprintf(s, "%lu", sz);
diff --git a/builtin-pack-objects.c b/builtin-pack-objects.c
index b5ed9ce..c456f49 100644
--- a/builtin-pack-objects.c
+++ b/builtin-pack-objects.c
@@ -1065,18 +1065,7 @@ static void check_object(struct object_entry *entry)
 	if (sha1_object_info(entry->sha1, type, &entry->size))
 		die("unable to get type of object %s",
 		    sha1_to_hex(entry->sha1));
-
-	if (!strcmp(type, commit_type)) {
-		entry->type = OBJ_COMMIT;
-	} else if (!strcmp(type, tree_type)) {
-		entry->type = OBJ_TREE;
-	} else if (!strcmp(type, blob_type)) {
-		entry->type = OBJ_BLOB;
-	} else if (!strcmp(type, tag_type)) {
-		entry->type = OBJ_TAG;
-	} else
-		die("unable to pack object %s of type %s",
-		    sha1_to_hex(entry->sha1), type);
+	entry->type = type_from_string(type);
 }
 
 static unsigned int check_delta_limit(struct object_entry *me, unsigned int n)
diff --git a/fast-import.c b/fast-import.c
index 5d040fd..aa9eac3 100644
--- a/fast-import.c
+++ b/fast-import.c
@@ -891,7 +891,7 @@ static int store_object(
 	SHA_CTX c;
 	z_stream s;
 
-	hdrlen = sprintf((char*)hdr,"%s %lu", type_names[type],
+	hdrlen = sprintf((char*)hdr,"%s %lu", typename(type),
 		(unsigned long)datlen) + 1;
 	SHA1_Init(&c);
 	SHA1_Update(&c, hdr, hdrlen);
@@ -1626,7 +1626,7 @@ static void file_change_m(struct branch *b)
 	} else if (oe) {
 		if (oe->type != OBJ_BLOB)
 			die("Not a blob (actually a %s): %s",
-				command_buf.buf, type_names[oe->type]);
+				command_buf.buf, typename(oe->type));
 	} else {
 		if (sha1_object_info(sha1, type, NULL))
 			die("Blob not found: %s", command_buf.buf);
@@ -1711,7 +1711,7 @@ static void cmd_from(struct branch *b)
 			char *buf;
 
 			buf = read_object_with_reference(b->sha1,
-				type_names[OBJ_COMMIT], &size, b->sha1);
+				commit_type, &size, b->sha1);
 			if (!buf || size < 46)
 				die("Not a valid commit: %s", from);
 			if (memcmp("tree ", buf, 5)
@@ -1895,7 +1895,7 @@ static void cmd_new_tag(void)
 		char *buf;
 
 		buf = read_object_with_reference(sha1,
-			type_names[OBJ_COMMIT], &size, sha1);
+			commit_type, &size, sha1);
 		if (!buf || size < 46)
 			die("Not a valid commit: %s", from);
 		free(buf);
@@ -1916,7 +1916,7 @@ static void cmd_new_tag(void)
 	size_dbuf(&new_data, 67+strlen(t->name)+strlen(tagger)+msglen);
 	sp = new_data.buffer;
 	sp += sprintf(sp, "object %s\n", sha1_to_hex(sha1));
-	sp += sprintf(sp, "type %s\n", type_names[OBJ_COMMIT]);
+	sp += sprintf(sp, "type %s\n", commit_type);
 	sp += sprintf(sp, "tag %s\n", t->name);
 	sp += sprintf(sp, "tagger %s\n", tagger);
 	*sp++ = '\n';
diff --git a/index-pack.c b/index-pack.c
index 365f8f3..c25cd40 100644
--- a/index-pack.c
+++ b/index-pack.c
@@ -605,13 +605,8 @@ static void fix_unresolved_deltas(int nr_unresolved)
 		data = read_sha1_file(d->base.sha1, type, &size);
 		if (!data)
 			continue;
-		if      (!strcmp(type, blob_type))   obj_type = OBJ_BLOB;
-		else if (!strcmp(type, tree_type))   obj_type = OBJ_TREE;
-		else if (!strcmp(type, commit_type)) obj_type = OBJ_COMMIT;
-		else if (!strcmp(type, tag_type))    obj_type = OBJ_TAG;
-		else die("base object %s is of type '%s'",
-			 sha1_to_hex(d->base.sha1), type);
 
+		obj_type = type_from_string(type);
 		find_delta_children(&d->base, &first, &last);
 		for (j = first; j <= last; j++) {
 			struct object_entry *child = objects + deltas[j].obj_no;
diff --git a/object.c b/object.c
index de244e2..37cedc0 100644
--- a/object.c
+++ b/object.c
@@ -18,11 +18,31 @@ struct object *get_indexed_object(unsigned int idx)
 	return obj_hash[idx];
 }
 
-const char *type_names[] = {
-	"none", "commit", "tree", "blob", "tag",
-	"bad type 5", "bad type 6", "delta", "bad",
+static const char *object_type_strings[] = {
+	NULL,		/* OBJ_NONE = 0 */
+	"commit",	/* OBJ_COMMIT = 1 */
+	"tree",		/* OBJ_TREE = 2 */
+	"blob",		/* OBJ_BLOB = 3 */
+	"tag",		/* OBJ_TAG = 4 */
 };
 
+const char *typename(unsigned int type)
+{
+	if (type >= ARRAY_SIZE(object_type_strings))
+		return NULL;
+	return object_type_strings[type];
+}
+
+int type_from_string(const char *str)
+{
+	int i;
+
+	for (i = 1; i < ARRAY_SIZE(object_type_strings); i++)
+		if (!strcmp(str, object_type_strings[i]))
+			return i;
+	die("invalid object type \"%s\"", str);
+}
+
 static unsigned int hash_obj(struct object *obj, unsigned int n)
 {
 	unsigned int hash = *(unsigned int *)obj->sha1;
diff --git a/object.h b/object.h
index caee733..ade4dae 100644
--- a/object.h
+++ b/object.h
@@ -36,16 +36,12 @@ struct object {
 };
 
 extern int track_object_refs;
-extern const char *type_names[9];
+
+extern const char *typename(unsigned int type);
+extern int type_from_string(const char *str);
 
 extern unsigned int get_max_object_index(void);
 extern struct object *get_indexed_object(unsigned int);
-
-static inline const char *typename(unsigned int type)
-{
-	return type_names[type > OBJ_BAD ? OBJ_BAD : type];
-}
-
 extern struct object_refs *lookup_object_refs(struct object *);
 
 /** Internal only **/
diff --git a/sha1_file.c b/sha1_file.c
index 8b7b68c..423ff0a 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -952,7 +952,7 @@ static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned lon
 
 	/* And generate the fake traditional header */
 	stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu",
-					 type_names[type], size);
+					 typename(type), size);
 	return 0;
 }
 
@@ -1195,7 +1195,7 @@ void packed_object_info_detail(struct packed_git *p,
 		case OBJ_TREE:
 		case OBJ_BLOB:
 		case OBJ_TAG:
-			strcpy(type, type_names[kind]);
+			strcpy(type, typename(kind));
 			*store_size = 0; /* notyet */
 			unuse_pack(&w_curs);
 			return;
@@ -1237,7 +1237,7 @@ static int packed_object_info(struct packed_git *p, unsigned long obj_offset,
 	case OBJ_TREE:
 	case OBJ_BLOB:
 	case OBJ_TAG:
-		strcpy(type, type_names[kind]);
+		strcpy(type, typename(kind));
 		if (sizep)
 			*sizep = size;
 		break;
@@ -1329,7 +1329,7 @@ void *unpack_entry(struct packed_git *p, unsigned long obj_offset,
 	case OBJ_TREE:
 	case OBJ_BLOB:
 	case OBJ_TAG:
-		strcpy(type, type_names[kind]);
+		strcpy(type, typename(kind));
 		*sizep = size;
 		retval = unpack_compressed_entry(p, &w_curs, curpos, size);
 		break;
@@ -1739,16 +1739,7 @@ static void setup_object_header(z_stream *stream, const char *type, unsigned lon
 			/* nothing */;
 		return;
 	}
-	if (!strcmp(type, blob_type))
-		obj_type = OBJ_BLOB;
-	else if (!strcmp(type, tree_type))
-		obj_type = OBJ_TREE;
-	else if (!strcmp(type, commit_type))
-		obj_type = OBJ_COMMIT;
-	else if (!strcmp(type, tag_type))
-		obj_type = OBJ_TAG;
-	else
-		die("trying to generate bogus object of type '%s'", type);
+	obj_type = type_from_string(type);
 	hdrlen = write_binary_header(stream->next_out, obj_type, len);
 	stream->total_out = hdrlen;
 	stream->next_out += hdrlen;

-- 
1.5.0.572.ge86d
Previous: Nicolas PitreNext: Nicolas Pitre
Message 5 of 16 in “various cleanups”
  1. Nicolas PitreFeb 26, 2007
  2. 1/6 sha1_file.c: cleanup hdr usageNicolas Pitre, Feb 26, 2007
  3. 2/6 sha1_file.c: cleanup "offset" usageNicolas Pitre, Feb 26, 2007
  4. 3/6 sha1_file.c: don't ignore an error condition in sha1_loose_object_info()Nicolas Pitre, Feb 26, 2007
  5. 4/6 formalize typename(), and add its reverse type_from_string()Nicolas Pitre, Feb 26, 2007
  6. 5/6 convert object type handling from a string to a numberNicolas Pitre, Feb 26, 2007
  7. 6/6 get rid of lookup_object_type()Nicolas Pitre, Feb 26, 2007
  8. Junio C HamanoFeb 27, 2007
  9. Junio C HamanoFeb 27, 2007
  10. Nicolas PitreFeb 27, 2007
  11. Nicolas PitreFeb 27, 2007
  12. Linus TorvaldsFeb 27, 2007
  13. Nicolas PitreFeb 27, 2007
  14. Shawn O. PearceFeb 27, 2007
  15. Nicolas PitreFeb 27, 2007
  16. Shawn O. PearceFeb 27, 2007

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