1 files changed, 93 insertions, 0 deletions
diff --git a/notes-cache.c b/notes-cache.c
new file mode 100644
index 0000000000..4c8984ede1
--- /dev/null
+++ b/notes-cache.c
@@ -0,0 +1,93 @@
+#include "cache.h"
+#include "notes-cache.h"
+#include "commit.h"
+#include "refs.h"
+
+static int notes_cache_match_validity(const char *ref, const char *validity)
+{
+	unsigned char sha1[20];
+	struct commit *commit;
+	struct pretty_print_context pretty_ctx;
+	struct strbuf msg = STRBUF_INIT;
+	int ret;
+
+	if (read_ref(ref, sha1) < 0)
+		return 0;
+
+	commit = lookup_commit_reference_gently(sha1, 1);
+	if (!commit)
+		return 0;
+
+	memset(&pretty_ctx, 0, sizeof(pretty_ctx));
+	format_commit_message(commit, "%s", &msg, &pretty_ctx);
+	strbuf_trim(&msg);
+
+	ret = !strcmp(msg.buf, validity);
+	strbuf_release(&msg);
+
+	return ret;
+}
+
+void notes_cache_init(struct notes_cache *c, const char *name,
+		     const char *validity)
+{
+	struct strbuf ref = STRBUF_INIT;
+	int flags = 0;
+
+	memset(c, 0, sizeof(*c));
+	c->validity = xstrdup(validity);
+
+	strbuf_addf(&ref, "refs/notes/%s", name);
+	if (!notes_cache_match_validity(ref.buf, validity))
+		flags = NOTES_INIT_EMPTY;
+	init_notes(&c->tree, ref.buf, combine_notes_overwrite, flags);
+	strbuf_release(&ref);
+}
+
+int notes_cache_write(struct notes_cache *c)
+{
+	unsigned char tree_sha1[20];
+	unsigned char commit_sha1[20];
+
+	if (!c || !c->tree.initialized || !c->tree.ref || !*c->tree.ref)
+		return -1;
+	if (!c->tree.dirty)
+		return 0;
+
+	if (write_notes_tree(&c->tree, tree_sha1))
+		return -1;
+	if (commit_tree(c->validity, tree_sha1, NULL, commit_sha1, NULL) < 0)
+		return -1;
+	if (update_ref("update notes cache", c->tree.ref, commit_sha1, NULL,
+		       0, QUIET_ON_ERR) < 0)
+		return -1;
+
+	return 0;
+}
+
+char *notes_cache_get(struct notes_cache *c, unsigned char key_sha1[20],
+		      size_t *outsize)
+{
+	const unsigned char *value_sha1;
+	enum object_type type;
+	char *value;
+	unsigned long size;
+
+	value_sha1 = get_note(&c->tree, key_sha1);
+	if (!value_sha1)
+		return NULL;
+	value = read_sha1_file(value_sha1, &type, &size);
+
+	*outsize = size;
+	return value;
+}
+
+int notes_cache_put(struct notes_cache *c, unsigned char key_sha1[20],
+		    const char *data, size_t size)
+{
+	unsigned char value_sha1[20];
+
+	if (write_sha1_file(data, size, "blob", value_sha1) < 0)
+		return -1;
+	return add_note(&c->tree, key_sha1, value_sha1, NULL);
+}