tree: use simple stack to remember the previous subtree line numbers

diff --git a/tig.c b/tig.c
index 541a8df49e2daded8a1b286a03c9308cff66d6cb..49848d67b459a81abf1edaaa8a935dd3535ea44d 100644 (file)
--- a/tig.c
+++ b/tig.c
@@ -2630,6 +2630,50 @@ static struct view_ops help_ops = {
  * Tree backend
  */
 
+struct tree_stack_entry {
+       struct tree_stack_entry *prev;  /* Entry below this in the stack */
+       unsigned long lineno;           /* Line number to restore */
+       char *name;                     /* Position of name in opt_path */
+};
+
+/* The top of the path stack. */
+static struct tree_stack_entry *tree_stack = NULL;
+unsigned long tree_lineno = 0;
+
+static void
+pop_tree_stack_entry(void)
+{
+       struct tree_stack_entry *entry = tree_stack;
+
+       tree_lineno = entry->lineno;
+       entry->name[0] = 0;
+       tree_stack = entry->prev;
+       free(entry);
+}
+
+static void
+push_tree_stack_entry(char *name, unsigned long lineno)
+{
+       struct tree_stack_entry *entry = calloc(1, sizeof(*entry));
+       size_t pathlen = strlen(opt_path);
+
+       if (!entry)
+               return;
+
+       entry->prev = tree_stack;
+       entry->name = opt_path + pathlen;
+       tree_stack = entry;
+
+       if (!string_format_from(opt_path, &pathlen, "%s/", name)) {
+               pop_tree_stack_entry();
+               return;
+       }
+
+       /* Move the current line to the first tree entry. */
+       tree_lineno = 1;
+       entry->lineno = lineno;
+}
+
 /* Parse output from git-ls-tree(1):
  *
  * 100644 blob fb0e31ea6cc679b7379631188190e975f5789c26        Makefile
@@ -2726,9 +2770,10 @@ tree_read(struct view *view, char *text)
        if (!add_line_text(view, text, type))
                return FALSE;
 
-       /* Move the current line to the first tree entry. */
-       if (first_read)
-               view->lineno++;
+       if (tree_lineno > view->lineno) {
+               view->lineno = tree_lineno;
+               tree_lineno = 0;
+       }
 
        return TRUE;
 }
@@ -2741,29 +2786,22 @@ tree_request(struct view *view, enum request request, struct line *line)
        if (request != REQ_ENTER)
                return request;
 
+       /* Cleanup the stack if the tree view is at a different tree. */
+       while (!*opt_path && tree_stack)
+               pop_tree_stack_entry();
+
        switch (line->type) {
        case LINE_TREE_DIR:
                /* Depending on whether it is a subdir or parent (updir?) link
                 * mangle the path buffer. */
                if (line == &view->line[1] && *opt_path) {
-                       size_t path_len = strlen(opt_path);
-                       char *dirsep = opt_path + path_len - 1;
-
-                       while (dirsep > opt_path && dirsep[-1] != '/')
-                               dirsep--;
-
-                       dirsep[0] = 0;
+                       pop_tree_stack_entry();
 
                } else {
-                       size_t pathlen = strlen(opt_path);
-                       size_t origlen = pathlen;
                        char *data = line->data;
                        char *basename = data + SIZEOF_TREE_ATTR;
 
-                       if (!string_format_from(opt_path, &pathlen, "%s/", basename)) {
-                               opt_path[origlen] = 0;
-                               return TRUE;
-                       }
+                       push_tree_stack_entry(basename, view->lineno);
                }
 
                /* Trees and subtrees share the same ID, so they are not not
@@ -2782,6 +2820,9 @@ tree_request(struct view *view, enum request request, struct line *line)
        }
 
        open_view(view, request, flags);
+       if (request == REQ_VIEW_TREE) {
+               view->lineno = tree_lineno;
+       }
 
        return REQ_NONE;
 }