[PATCH/RFC/GSoC 02/17] sha1_name: implement get_oid() and friends

[Paul Tan <pyokagan@gmail.com>]

5f7817c (define a structure for object IDs, 2015-03-13) introduced the
object_id struct to replace the used of unsigned char[] arrays to hold
object IDs. This gives us the benefit of compile-time checking for
misuse.

To fully take advantage of compile-time type-checking, introduce the
get_oid_*() functions which wrap the corresponding get_sha1_*()
functions.

Signed-off-by: Paul Tan <pyokagan@gmail.com>
---
 cache.h     |  6 ++++++
 sha1_name.c | 30 ++++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+)

diff --git a/cache.h b/cache.h
index b829410..55d443e 100644
--- a/cache.h
+++ b/cache.h
@@ -1116,11 +1116,17 @@ struct object_context {
 #define GET_SHA1_ONLY_TO_DIE    04000
 
 extern int get_sha1(const char *str, unsigned char *sha1);
+extern int get_oid(const char *str, struct object_id *oid);
 extern int get_sha1_commit(const char *str, unsigned char *sha1);
+extern int get_oid_commit(const char *str, struct object_id *oid);
 extern int get_sha1_committish(const char *str, unsigned char *sha1);
+extern int get_oid_committish(const char *str, struct object_id *oid);
 extern int get_sha1_tree(const char *str, unsigned char *sha1);
+extern int get_oid_tree(const char *str, struct object_id *oid);
 extern int get_sha1_treeish(const char *str, unsigned char *sha1);
+extern int get_oid_treeish(const char *str, struct object_id *oid);
 extern int get_sha1_blob(const char *str, unsigned char *sha1);
+extern int get_oid_blob(const char *str, struct object_id *oid);
 extern void maybe_die_on_misspelt_object_name(const char *name, const char *prefix);
 extern int get_sha1_with_context(const char *str, unsigned flags, unsigned char *sha1, struct object_context *orc);
 
diff --git a/sha1_name.c b/sha1_name.c
index 3acf221..307dfad 100644
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -1214,6 +1214,11 @@ int get_sha1(const char *name, unsigned char *sha1)
 	return get_sha1_with_context(name, 0, sha1, &unused);
 }
 
+int get_oid(const char *name, struct object_id *oid)
+{
+	return get_sha1(name, oid->hash);
+}
+
 /*
  * Many callers know that the user meant to name a commit-ish by
  * syntactical positions where the object name appears.  Calling this
@@ -1231,6 +1236,11 @@ int get_sha1_committish(const char *name, unsigned char *sha1)
 				     sha1, &unused);
 }
 
+int get_oid_committish(const char *name, struct object_id *oid)
+{
+	return get_sha1_committish(name, oid->hash);
+}
+
 int get_sha1_treeish(const char *name, unsigned char *sha1)
 {
 	struct object_context unused;
@@ -1238,6 +1248,11 @@ int get_sha1_treeish(const char *name, unsigned char *sha1)
 				     sha1, &unused);
 }
 
+int get_oid_treeish(const char *name, struct object_id *oid)
+{
+	return get_sha1_treeish(name, oid->hash);
+}
+
 int get_sha1_commit(const char *name, unsigned char *sha1)
 {
 	struct object_context unused;
@@ -1245,6 +1260,11 @@ int get_sha1_commit(const char *name, unsigned char *sha1)
 				     sha1, &unused);
 }
 
+int get_oid_commit(const char *name, struct object_id *oid)
+{
+	return get_sha1_commit(name, oid->hash);
+}
+
 int get_sha1_tree(const char *name, unsigned char *sha1)
 {
 	struct object_context unused;
@@ -1252,6 +1272,11 @@ int get_sha1_tree(const char *name, unsigned char *sha1)
 				     sha1, &unused);
 }
 
+int get_oid_tree(const char *name, struct object_id *oid)
+{
+	return get_sha1_tree(name, oid->hash);
+}
+
 int get_sha1_blob(const char *name, unsigned char *sha1)
 {
 	struct object_context unused;
@@ -1259,6 +1284,11 @@ int get_sha1_blob(const char *name, unsigned char *sha1)
 				     sha1, &unused);
 }
 
+int get_oid_blob(const char *name, struct object_id *oid)
+{
+	return get_sha1_blob(name, oid->hash);
+}
+
 /* Must be called only when object_name:filename doesn't exist. */
 static void diagnose_invalid_sha1_path(const char *prefix,
 				       const char *filename,
-- 
2.7.0