Merge branch 'nd/worktree-various-heads'

The experimental "multiple worktree" feature gains more safety to
forbid operations on a branch that is checked out or being actively
worked on elsewhere, by noticing that e.g. it is being rebased.

* nd/worktree-various-heads:
  branch: do not rename a branch under bisect or rebase
  worktree.c: check whether branch is bisected in another worktree
  wt-status.c: split bisect detection out of wt_status_get_state()
  worktree.c: check whether branch is rebased in another worktree
  worktree.c: avoid referencing to worktrees[i] multiple times
  wt-status.c: make wt_status_check_rebase() work on any worktree
  wt-status.c: split rebase detection out of wt_status_get_state()
  path.c: refactor and add worktree_git_path()
  worktree.c: mark current worktree
  worktree.c: make find_shared_symref() return struct worktree *
  worktree.c: store "id" instead of "git_dir"
  path.c: add git_common_path() and strbuf_git_common_path()
  dir.c: rename str(n)cmp_icase to fspath(n)cmp

1 files changed, 43 insertions, 20 deletions

diff --git a/wt-status.c b/wt-status.c
index 16856305ca..4f27bd62af 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -15,6 +15,7 @@
 #include "column.h"
 #include "strbuf.h"
 #include "utf8.h"
+#include "worktree.h"
 
 static const char cut_line[] =
 "------------------------ >8 ------------------------\n";
@@ -1263,13 +1264,13 @@ static void show_bisect_in_progress(struct wt_status *s,
 /*
  * Extract branch information from rebase/bisect
  */
-static char *read_and_strip_branch(const char *path)
+static char *get_branch(const struct worktree *wt, const char *path)
 {
 	struct strbuf sb = STRBUF_INIT;
 	unsigned char sha1[20];
 	const char *branch_name;
 
-	if (strbuf_read_file(&sb, git_path("%s", path), 0) <= 0)
+	if (strbuf_read_file(&sb, worktree_git_path(wt, "%s", path), 0) <= 0)
 		goto got_nothing;
 
 	while (sb.len && sb.buf[sb.len - 1] == '\n')
@@ -1361,40 +1362,62 @@ static void wt_status_get_detached_from(struct wt_status_state *state)
 	strbuf_release(&cb.buf);
 }
 
-void wt_status_get_state(struct wt_status_state *state,
-			 int get_detached_from)
+int wt_status_check_rebase(const struct worktree *wt,
+			   struct wt_status_state *state)
 {
 	struct stat st;
-	unsigned char sha1[20];
 
-	if (!stat(git_path_merge_head(), &st)) {
-		state->merge_in_progress = 1;
-	} else if (!stat(git_path("rebase-apply"), &st)) {
-		if (!stat(git_path("rebase-apply/applying"), &st)) {
+	if (!stat(worktree_git_path(wt, "rebase-apply"), &st)) {
+		if (!stat(worktree_git_path(wt, "rebase-apply/applying"), &st)) {
 			state->am_in_progress = 1;
-			if (!stat(git_path("rebase-apply/patch"), &st) && !st.st_size)
+			if (!stat(worktree_git_path(wt, "rebase-apply/patch"), &st) && !st.st_size)
 				state->am_empty_patch = 1;
 		} else {
 			state->rebase_in_progress = 1;
-			state->branch = read_and_strip_branch("rebase-apply/head-name");
-			state->onto = read_and_strip_branch("rebase-apply/onto");
+			state->branch = get_branch(wt, "rebase-apply/head-name");
+			state->onto = get_branch(wt, "rebase-apply/onto");
 		}
-	} else if (!stat(git_path("rebase-merge"), &st)) {
-		if (!stat(git_path("rebase-merge/interactive"), &st))
+	} else if (!stat(worktree_git_path(wt, "rebase-merge"), &st)) {
+		if (!stat(worktree_git_path(wt, "rebase-merge/interactive"), &st))
 			state->rebase_interactive_in_progress = 1;
 		else
 			state->rebase_in_progress = 1;
-		state->branch = read_and_strip_branch("rebase-merge/head-name");
-		state->onto = read_and_strip_branch("rebase-merge/onto");
+		state->branch = get_branch(wt, "rebase-merge/head-name");
+		state->onto = get_branch(wt, "rebase-merge/onto");
+	} else
+		return 0;
+	return 1;
+}
+
+int wt_status_check_bisect(const struct worktree *wt,
+			   struct wt_status_state *state)
+{
+	struct stat st;
+
+	if (!stat(worktree_git_path(wt, "BISECT_LOG"), &st)) {
+		state->bisect_in_progress = 1;
+		state->branch = get_branch(wt, "BISECT_START");
+		return 1;
+	}
+	return 0;
+}
+
+void wt_status_get_state(struct wt_status_state *state,
+			 int get_detached_from)
+{
+	struct stat st;
+	unsigned char sha1[20];
+
+	if (!stat(git_path_merge_head(), &st)) {
+		state->merge_in_progress = 1;
+	} else if (wt_status_check_rebase(NULL, state)) {
+		;		/* all set */
 	} else if (!stat(git_path_cherry_pick_head(), &st) &&
 			!get_sha1("CHERRY_PICK_HEAD", sha1)) {
 		state->cherry_pick_in_progress = 1;
 		hashcpy(state->cherry_pick_head_sha1, sha1);
 	}
-	if (!stat(git_path("BISECT_LOG"), &st)) {
-		state->bisect_in_progress = 1;
-		state->branch = read_and_strip_branch("BISECT_START");
-	}
+	wt_status_check_bisect(NULL, state);
 	if (!stat(git_path_revert_head(), &st) &&
 	    !get_sha1("REVERT_HEAD", sha1)) {
 		state->revert_in_progress = 1;