Merge commit 'b319ef7' into jc/maint-fix-test-perm

* commit 'b319ef7': (8132 commits)
  Add a small patch-mode testing library
  git-apply--interactive: Refactor patch mode code
  t8005: Nobody writes Russian in shift_jis
  Fix severe breakage in "git-apply --whitespace=fix"
  Update release notes for 1.6.4
  After renaming a section, print any trailing variable definitions
  Make section_name_match start on '[', and return the length on success
  send-email: detect cycles in alias expansion
  Show the presence of untracked files in the bash prompt.
  SunOS grep does not understand -C<n> nor -e
  Fix export_marks() error handling.
  git repack: keep commits hidden by a graft
  Add a test showing that 'git repack' throws away grafted-away parents
  git branch: clean up detached branch handling
  git branch: avoid unnecessary object lookups
  git branch: fix performance problem
  git svn: fix shallow clone when upstream revision is too new
  do_one_ref(): null_sha1 check is not about broken ref
  configure.ac: properly unset NEEDS_SSL_WITH_CRYPTO when sha1 func is missing
  janitor: useless checks before free
  ...

1 files changed, 55 insertions, 0 deletions

diff --git a/editor.c b/editor.c
new file mode 100644
index 000000000..4d469d076
--- /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;
+}