AnyPS5/docs/dev/debt/libSceLibcInternal.md

libSceLibcInternal technical debt

Unknown function info

• _sceLibcInternalThreadAtexit, _sceLibcInternalThreadDtors (libSceLibcInternal) - FreeBSD __cxa_thread_atexit semantics assumed; a null or non-image destructor and an allocation failure throw
• _sceLibcInternalForceTlsDestructor (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 (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 (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 (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 (libSceLibcInternal) - the directory stream starts at the directory's first entry, while FreeBSD's fdopendir 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 (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 (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 (libSceLibcInternal) follow FreeBSD 11 getopt.c and 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