Notes API: get_commit_notes() -> format_note() + remove the commit restriction

There is really no reason why only commit objects can be annotated. By
changing the struct commit parameter to get_commit_notes() into a sha1 we
gain the ability to annotate any object type. To reflect this in the function
naming as well, we rename get_commit_notes() to format_note().

This patch also fixes comments and variable names throughout notes.c as a
consequence of the removal of the unnecessary 'commit' restriction.

Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

notes.c

@@ -1,5 +1,4 @@
 #include "cache.h"
-#include "commit.h"
 #include "notes.h"
 #include "utf8.h"
 #include "strbuf.h"
@@ -24,10 +23,10 @@ struct int_node {
 /*
  * Leaf nodes come in two variants, note entries and subtree entries,
  * distinguished by the LSb of the leaf node pointer (see above).
- * As a note entry, the key is the SHA1 of the referenced commit, and the
+ * As a note entry, the key is the SHA1 of the referenced object, and the
  * value is the SHA1 of the note object.
  * As a subtree entry, the key is the prefix SHA1 (w/trailing NULs) of the
- * referenced commit, using the last byte of the key to store the length of
+ * referenced object, using the last byte of the key to store the length of
  * the prefix. The value is the SHA1 of the tree object containing the notes
  * subtree.
  */
@@ -210,7 +209,7 @@ static void note_tree_insert(struct int_node *tree, unsigned char n,
 				if (concatenate_notes(l->val_sha1,
 						entry->val_sha1))
 					die("failed to concatenate note %s "
-					    "into note %s for commit %s",
+					    "into note %s for object %s",
 					    sha1_to_hex(entry->val_sha1),
 					    sha1_to_hex(l->val_sha1),
 					    sha1_to_hex(l->key_sha1));
@@ -298,7 +297,7 @@ static int get_sha1_hex_segment(const char *hex, unsigned int hex_len,
 static void load_subtree(struct leaf_node *subtree, struct int_node *node,
 		unsigned int n)
 {
-	unsigned char commit_sha1[20];
+	unsigned char object_sha1[20];
 	unsigned int prefix_len;
 	void *buf;
 	struct tree_desc desc;
@@ -311,23 +310,23 @@ static void load_subtree(struct leaf_node *subtree, struct int_node *node,
 
 	prefix_len = subtree->key_sha1[19];
 	assert(prefix_len * 2 >= n);
-	memcpy(commit_sha1, subtree->key_sha1, prefix_len);
+	memcpy(object_sha1, subtree->key_sha1, prefix_len);
 	while (tree_entry(&desc, &entry)) {
 		int len = get_sha1_hex_segment(entry.path, strlen(entry.path),
-				commit_sha1 + prefix_len, 20 - prefix_len);
+				object_sha1 + prefix_len, 20 - prefix_len);
 		if (len < 0)
 			continue; /* entry.path is not a SHA1 sum. Skip */
 		len += prefix_len;
 
 		/*
-		 * If commit SHA1 is complete (len == 20), assume note object
-		 * If commit SHA1 is incomplete (len < 20), assume note subtree
+		 * If object SHA1 is complete (len == 20), assume note object
+		 * If object SHA1 is incomplete (len < 20), assume note subtree
 		 */
 		if (len <= 20) {
 			unsigned char type = PTR_TYPE_NOTE;
 			struct leaf_node *l = (struct leaf_node *)
 				xcalloc(sizeof(struct leaf_node), 1);
-			hashcpy(l->key_sha1, commit_sha1);
+			hashcpy(l->key_sha1, object_sha1);
 			hashcpy(l->val_sha1, entry.sha1);
 			if (len < 20) {
 				if (!S_ISDIR(entry.mode))
@@ -343,12 +342,12 @@ static void load_subtree(struct leaf_node *subtree, struct int_node *node,
 
 static void initialize_notes(const char *notes_ref_name)
 {
-	unsigned char sha1[20], commit_sha1[20];
+	unsigned char sha1[20], object_sha1[20];
 	unsigned mode;
 	struct leaf_node root_tree;
 
-	if (!notes_ref_name || read_ref(notes_ref_name, commit_sha1) ||
-	    get_tree_entry(commit_sha1, "", sha1, &mode))
+	if (!notes_ref_name || read_ref(notes_ref_name, object_sha1) ||
+	    get_tree_entry(object_sha1, "", sha1, &mode))
 		return;
 
 	hashclr(root_tree.key_sha1);
@@ -356,9 +355,9 @@ static void initialize_notes(const char *notes_ref_name)
 	load_subtree(&root_tree, &root_node, 0);
 }
 
-static unsigned char *lookup_notes(const unsigned char *commit_sha1)
+static unsigned char *lookup_notes(const unsigned char *object_sha1)
 {
-	struct leaf_node *found = note_tree_find(&root_node, 0, commit_sha1);
+	struct leaf_node *found = note_tree_find(&root_node, 0, object_sha1);
 	if (found)
 		return found->val_sha1;
 	return NULL;
@@ -371,7 +370,7 @@ void free_notes(void)
 	initialized = 0;
 }
 
-void get_commit_notes(const struct commit *commit, struct strbuf *sb,
+void format_note(const unsigned char *object_sha1, struct strbuf *sb,
 		const char *output_encoding, int flags)
 {
 	static const char utf8[] = "utf-8";
@@ -390,7 +389,7 @@ void get_commit_notes(const struct commit *commit, struct strbuf *sb,
 		initialized = 1;
 	}
 
-	sha1 = lookup_notes(commit->object.sha1);
+	sha1 = lookup_notes(object_sha1);
 	if (!sha1)
 		return;
 

notes.h

@@ -4,10 +4,19 @@
 /* Free (and de-initialize) the internal notes tree structure */
 void free_notes(void);
 
+/* Flags controlling how notes are formatted */
 #define NOTES_SHOW_HEADER 1
 #define NOTES_INDENT 2
 
-void get_commit_notes(const struct commit *commit, struct strbuf *sb,
+/*
+ * Fill the given strbuf with the notes associated with the given object.
+ *
+ * If the internal notes structure is not initialized, it will be auto-
+ * initialized to the default value (see documentation for init_notes() above).
+ *
+ * 'flags' is a bitwise combination of the above formatting flags.
+ */
+void format_note(const unsigned char *object_sha1, struct strbuf *sb,
 		const char *output_encoding, int flags);
 
 #endif

pretty.c

@@ -775,8 +775,8 @@ static size_t format_commit_one(struct strbuf *sb, const char *placeholder,
 		}
 		return 0;	/* unknown %g placeholder */
 	case 'N':
-		get_commit_notes(commit, sb, git_log_output_encoding ?
-			     git_log_output_encoding : git_commit_encoding, 0);
+		format_note(commit->object.sha1, sb, git_log_output_encoding ?
+			    git_log_output_encoding : git_commit_encoding, 0);
 		return 1;
 	}
 
@@ -1095,8 +1095,8 @@ void pretty_print_commit(enum cmit_fmt fmt, const struct commit *commit,
 		strbuf_addch(sb, '\n');
 
 	if (context->show_notes)
-		get_commit_notes(commit, sb, encoding,
-				 NOTES_SHOW_HEADER | NOTES_INDENT);
+		format_note(commit->object.sha1, sb, encoding,
+			    NOTES_SHOW_HEADER | NOTES_INDENT);
 
 	free(reencoded);
 }