# libSceLibcInternal technical debt

### Unknown function info

- [_sceLibcInternalThreadAtexit, _sceLibcInternalThreadDtors](../../../core/libs/prx/libSceLibcInternal/Export.cpp) (libSceLibcInternal) - FreeBSD `__cxa_thread_atexit` semantics assumed; a null or non-image destructor and an allocation failure throw
- [_sceLibcInternalForceTlsDestructor](../../../core/libs/prx/libSceLibcInternal/Export.cpp) (libSceLibcInternal) - behaviour follows `sceLibcForceTlsDestructor(int)` in a title's `libc.prx` (disassembly): the calling thread's destructors whose dso belongs to the module run newest first, only if the dso's module is loaded and the dso points to itself, in up to 4 passes. The return type is unknown (that function returns nothing), 0 is returned. The module of each dso is looked up when the destructors are forced, not when they are registered as `libc.prx` does

### Functional

- [makecontext](../../../core/libs/prx/libSceLibcInternal/UserContext.cpp) (libSceLibcInternal) follows FreeBSD 11's `lib/libc/amd64/gen/makecontext.c`: at most six arguments, a stack of at least `MINSIGSTKSZ` (2048) bytes, and `exit(0)` when the function returns with no `uc_link`. The console's version is not verified
- [makecontext](../../../core/libs/prx/libSceLibcInternal/UserContext.cpp) (libSceLibcInternal) on Windows pins its stack writable until a later `makecontext` stack overlaps it, since nothing tells the library when the guest frees the stack
- [Thread exit destructors](../../../core/libs/prx/libSceLibcInternal/Export.cpp) (libSceLibcInternal) run when a libkernel thread finishes; on the main or a host thread only `_sceLibcInternalThreadDtors` runs them, as `exit` does, else they are dropped
- [fdopendir](../../../core/libs/prx/libSceLibcInternal/Directory.cpp) (libSceLibcInternal) - the directory stream starts at the directory's first entry, while FreeBSD's [`fdopendir`](https://github.com/freebsd/freebsd-src/blob/release/11.0.0/lib/libc/gen/opendir.c#L67-L74) reads from the descriptor's current offset, and `FD_CLOEXEC` is not set on the descriptor. As in FreeBSD, a descriptor that is not open fails with `EBADF`, one that is not a directory with `ENOTDIR` (both leave it open), and `closedir` closes it
- [fstatvfs](../../../core/libs/prx/libSceLibcInternal/FilesystemStatistics.cpp) (libSceLibcInternal) converts `_fstatfs` to the 88-byte `struct statvfs` as FreeBSD 9.2's `sfs2svfs` does (`f_bsize` from the transfer size, `f_frsize` from the block size, `f_favail` equal to `f_ffree`, `f_fsid` 0, `ST_RDONLY` and `ST_NOSUID` only). Differences: `f_namemax` is the `statfs` value, not `fpathconf(_PC_NAME_MAX)`; negative `f_bavail` and `f_ffree` wrap to unsigned without `EOVERFLOW`, as the same-width copy in FreeBSD does; inode counts are 0 on Windows, inherited from `_fstatfs`; a null output returns `EFAULT` after the descriptor is validated, where FreeBSD would fault. Layout and conversion are unverified against the PS5 library (PS5MC imports `fstatvfs` but was not run)
- [posix_spawn and posix_spawnp](../../../core/libs/prx/libSceLibcInternal/Spawn.cpp) (libSceLibcInternal) throw: creating a child process is not supported. PPSA99305 (Dusklight) and PPSA99309 (Wind Waker) stop on `main` at unresolved import `44hlATrd47U` (`posix_spawnattr_init`); a run with this PR has not established how far either title gets, and process creation still throws. The attribute and file action calls keep FreeBSD 11.4's objects, so a real `posix_spawn` would have to apply them in the child. Null or uninitialized objects, which FreeBSD dereferences, throw.
- [getopt, getopt_long](../../../core/libs/prx/libSceLibcInternal/Getopt.cpp) (libSceLibcInternal) follow FreeBSD 11 [getopt.c](https://github.com/freebsd/freebsd-src/blob/8c639945a44588f6cfdddfb057bb5aad88735da0/lib/libc/stdlib/getopt.c) and [getopt_long.c](https://github.com/freebsd/freebsd-src/blob/8c639945a44588f6cfdddfb057bb5aad88735da0/lib/libc/stdlib/getopt_long.c) with `GNU_COMPATIBLE`: `getopt` does not permute, `getopt_long` permutes unless `POSIXLY_CORRECT` is set in the guest environment or the option string starts with `+`, and the exported `opterr`, `optind`, `optopt`, `optreset` and `optarg` start at 1, 1, 0, 0 and null. Warnings go to the guest's current `stderr` prefixed with `__progname`, where FreeBSD's `warnx` keeps the `stderr` of its first call. A null `getopt` option string, a null argument vector or argument, a negative `optind` and an `optind` moved inside a pending permutation throw where FreeBSD faults. `getopt_long_only` is not exported. That the console's `libSceLibcInternal` uses this FreeBSD code is unverified