Needed to compile most things on -portable.

ok jamsek

The OpenBSD version of seq defaults to an increment value of -1 here. On Debian we have to set the increment value to -1 explicitly. Otherwise, seq produces no output at all and the test fails.

Prompted by questions from Johannes Kastl.

These has to be looked for portably. <sys/tree.h> recently reappeared due to TAILQ -> RB_* changes upstream.

When using libbsd, ensure that we define HAVE_TREE_H; this means libbsd's <sys/tree.h> is used over the compat version which stops redefinition warnings from libbsd.

ok stsp@

ok stsp@

While here, style(9) the adjacent block: remove function call from initializer. ok stsp@

In the rare case views are smaller in height than the first line number after the view's header lines (i.e., [2,5] depending on the view), we can decrement the selected entry index into negative values; clamp it to 0. Add a log view test case covering this path by opening a child tree view and toggling fullscreen. ok stsp@

In the rare case a tree view is smaller than four lines in height, the last_displayed_entry is NULL. Check this condition on a scroll down event with j/down arrow or ^f/pgdn to guard a NULL got_tree_entry from being passed to got_tree_entry_get_next() where it is dereferenced. And add a test case covering this path. ok stsp@

If a nested log view is opened, don't reuse the work tree's base commit index from the initial `tog log` invocation because it is based on the initial commit queue. If it has become invalid, an incorrect log view commit entry is painted with the base commit marker. Reset the index whenever opening nested log views so that it is recomputed, and write a regression test to cover this case. ok stsp@

Test for the error case when selecting tags that point to non-commit objects. And test the valid case of selecting nested tags that resolve to commit objects. ok stsp@

Tags can point to all git objects: commits, trees, blobs, and tags. Selecting a tag that points to any object other than a commit causes a fatal error. Instead, report a message to the status line. Similarly, nested tags may resolve to a commit, which currently errors. Instead, keep peeling till we reach the bottom and if it's a commit, use it for the requested view. ok stsp@

ok stsp@

When the commit graph has been traversed, we set the log_complete flag to signal the main thread that we've completed iterating commit history, which request_log_commits() checks and, if set, returns early instead of calling trigger_log_thread(). If called, trigger_log_thread() wakes the log thread, then waits on the log thread to unblock when another commit has been loaded. There's a race between the log thread setting the log_complete flag and request_log_commits() checking it, which causes trigger_load_thread() to wait on a signal that never unblocks because there are no more commits to be loaded. ok stsp@

Coverage for the case fixed in 74bea526c5. ok stsp@

When the log view T keymap is used, the selected_entry is passed to browse_commit_tree() to open a tree view of the repository as at the selected commit, which passes the selected_entry->id member to open_tree_view() to open the commit. The id member, which is a NULL pointer in work tree entries, is dereferenced so we segfault. If the T keymap is used on a work tree entry, use the base commit id instead, which we must have if a work tree entry is selected. ok stsp@