1 files changed, 55 insertions, 0 deletions
diff --git a/editor.c b/editor.c
new file mode 100644
index 0000000000..4d469d076b
--- /dev/null
+++ b/editor.c
@@ -0,0 +1,55 @@
+#include "cache.h"
+#include "strbuf.h"
+#include "run-command.h"
+
+int launch_editor(const char *path, struct strbuf *buffer, const char *const *env)
+{
+	const char *editor, *terminal;
+
+	editor = getenv("GIT_EDITOR");
+	if (!editor && editor_program)
+		editor = editor_program;
+	if (!editor)
+		editor = getenv("VISUAL");
+	if (!editor)
+		editor = getenv("EDITOR");
+
+	terminal = getenv("TERM");
+	if (!editor && (!terminal || !strcmp(terminal, "dumb")))
+		return error("Terminal is dumb but no VISUAL nor EDITOR defined.");
+
+	if (!editor)
+		editor = "vi";
+
+	if (strcmp(editor, ":")) {
+		size_t len = strlen(editor);
+		int i = 0;
+		int failed;
+		const char *args[6];
+		struct strbuf arg0 = STRBUF_INIT;
+
+		if (strcspn(editor, "$ \t'") != len) {
+			/* there are specials */
+			strbuf_addf(&arg0, "%s \"$@\"", editor);
+			args[i++] = "sh";
+			args[i++] = "-c";
+			args[i++] = arg0.buf;
+		}
+		args[i++] = editor;
+		args[i++] = path;
+		args[i] = NULL;
+
+		failed = run_command_v_opt_cd_env(args, 0, NULL, env);
+		strbuf_release(&arg0);
+		if (failed)
+			return error("There was a problem with the editor '%s'.",
+					editor);
+	}
+
+	if (!buffer)
+		return 0;
+	if (strbuf_read_file(buffer, path, 0) < 0)
+		return error("could not read file '%s': %s",
+				path, strerror(errno));
+	return 0;
+}