[PATCH/RFC/GSoC 16/17] editor: implement git_sequence_editor() and launch_sequence_editor()

[Paul Tan <pyokagan@gmail.com>]

Signed-off-by: Paul Tan <pyokagan@gmail.com>
---
 cache.h  |  1 +
 editor.c | 27 +++++++++++++++++++++++++--
 strbuf.h |  1 +
 3 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/cache.h b/cache.h
index aa5e97c..d7a6fc6 100644
--- a/cache.h
+++ b/cache.h
@@ -1222,6 +1222,7 @@ extern const char *fmt_name(const char *name, const char *email);
 extern const char *ident_default_name(void);
 extern const char *ident_default_email(void);
 extern const char *git_editor(void);
+extern const char *git_sequence_editor(void);
 extern const char *git_pager(int stdout_is_tty);
 extern int git_ident_config(const char *, const char *, void *);
 
diff --git a/editor.c b/editor.c
index 01c644c..4c5874b 100644
--- a/editor.c
+++ b/editor.c
@@ -29,10 +29,22 @@ const char *git_editor(void)
 	return editor;
 }
 
-int launch_editor(const char *path, struct strbuf *buffer, const char *const *env)
+const char *git_sequence_editor(void)
 {
-	const char *editor = git_editor();
+	const char *sequence_editor = getenv("GIT_SEQUENCE_EDITOR");
+
+	if (sequence_editor && *sequence_editor)
+		return sequence_editor;
 
+	git_config_get_string_const("sequence.editor", &sequence_editor);
+	if (sequence_editor && *sequence_editor)
+		return sequence_editor;
+
+	return git_editor();
+}
+
+static int launch_specific_editor(const char *editor, const char *path, struct strbuf *buffer, const char *const *env)
+{
 	if (!editor)
 		return error("Terminal is dumb, but EDITOR unset");
 
@@ -65,5 +77,16 @@ int launch_editor(const char *path, struct strbuf *buffer, const char *const *en
 	if (strbuf_read_file(buffer, path, 0) < 0)
 		return error("could not read file '%s': %s",
 				path, strerror(errno));
+
 	return 0;
 }
+
+int launch_editor(const char *path, struct strbuf *buffer, const char *const *env)
+{
+	return launch_specific_editor(git_editor(), path, buffer, env);
+}
+
+int launch_sequence_editor(const char *path, struct strbuf *buffer, const char *const *env)
+{
+	return launch_specific_editor(git_sequence_editor(), path, buffer, env);
+}
diff --git a/strbuf.h b/strbuf.h
index f72fd14..aebdcd7 100644
--- a/strbuf.h
+++ b/strbuf.h
@@ -524,6 +524,7 @@ extern void strbuf_add_unique_abbrev(struct strbuf *sb,
  * file's contents are not read into the buffer upon completion.
  */
 extern int launch_editor(const char *path, struct strbuf *buffer, const char *const *env);
+extern int launch_sequence_editor(const char *path, struct strbuf *buffer, const char *const *env);
 
 extern void strbuf_add_lines(struct strbuf *sb, const char *prefix, const char *buf, size_t size);
 
-- 
2.7.0