Add RAII wrappers for unmounting PHYSFS paths. Use them in places that
previously handled unmounting explicitly. Also, use it for descent.hog
/ descent2.hog, which previously were left mounted indefinitely.
Some callers will need access to the computed path. Change the callers
to pass in a buffer for this path, and have PHYSFSX_addRelToSearchPath
fill that buffer directly.
gcc-10 warns that if immediate_directories were very large, the sprintf
result would be truncated. This is true, but a user is extremely
unlikely to have enough directories to trigger this code path. Handle
the warning by explicitly returning an empty string if truncation would
otherwise occur. This is not strictly correct, but it can be handled
with very little code, eliminates the warning, and is unlikely to matter
in practice.
The historical savegame format cannot support finding a mission in a
subdirectory. Add a backwards-incompatible modification to store the
full path in the savegame, and store it in a way that old versions will
fail gracefully.[1] When loading demos, or legacy savegames, search for
the mission in all available directories. Demos are still written with
an unqualified path because the demo loading code would crash if given
an oversized path. Mission names sent over the network as part of
multiplayer use the guess logic now, so that guests do not need to have
the mission in the same path as the host.
[1] Versions affected by issue #486 may fail ungracefully.
Reported-by: AlumiuN <https://github.com/dxx-rebirth/dxx-rebirth/issues/491>
- In D2X, do not accept Descent2-specific directives from Descent 1
`.msn` files.
- Set the descent_version field correctly in the `mle`. Previously,
`.msn` was set to descent1 and all `.mn2` were set to descent2,
regardless of whether the `.mn2` used `name`, `xname`, `zname`, or
`!name`.
- Avoid rewinding the file and rereading the same line while checking
the possible name types.
- Avoid recomputing end-of-string when it is already known.
- Avoid re-reading the mission file's version when the mission is
chosen. Instead, use the version that was recorded when the mission
was loaded into the mission list. This also fixes a bug where Descent
1 `.msn` files would be classified as descent_version_type::descent2
since both use `name =`, but that string has a different meaning
depending on whether the file is `.msn` or `.mn2`.
AlumiuN reported a crash when a save game is unable to load the
underlying mission. The crash is because the game proceeds to load the
savegame onto whatever level was loaded before this mission, which will
usually result in fatal inconsistencies in the data.
This commit does not fix the cause of the inability to load the mission,
but instead fixes the logic so that the user gets a reasonable error
message advising that the mission failed to load. This was
unintentionally broken in db80a88ad2 when the sense of the return
value was inverted, and the fallthrough case was not adjusted. This
impacts all uses of `load_mission_by_name`, though in practice restoring
from a savegame is the most obvious way to hit the problem.
Reported-by: AlumiuN <https://github.com/dxx-rebirth/dxx-rebirth/issues/486> (indirectly)
Fixes: db80a88ad2 ("Improve error message on failure to load mission")
Mission sorting is handled in a top-level function after the missions
have been found, so that the special case to promote built-in missions
is only applied at the top level. Unfortunately, this meant that
subdirectories were not sorted. Add an explicit sort in a path specific
to subdirectory handling.
Reported-by: AlumiuN <https://github.com/dxx-rebirth/dxx-rebirth/issues/472>
PhysFS 3.0 tests whether archive members are directories, but treats a
symbolic link that points to a directory as distinct from the underlying
directory, even when symlink following is enabled. As a result, if
$D2X_REBIRTH_HOME/missions is a symlink to a directory, then it is
ignored and no missions are available. In PhysFS 2.0, the link was
followed and the missions were available.
Add a trailing dot to the path, which already has a trailing slash, to
force PhysFS to consider the underlying directory, not the link.
clang warns that this interferes with copy elision. The generated code
is slightly worse after following clang's advice and removing this, but
this is not a hot path, so take the hit to silence clang instead of
complicating the source.
Fixes: d97afc2ad5 ("Retain directory structure in New Game dialog")
Add macro cf_assert ("control flow" assert) to hint to gcc that certain
conditions are impossible. Use it to avoid generating range checks for
situations that never happen. If the event did happen, the only
consequence would be truncated UI text, rather than a correctness
problem.
