Merge pull request #12577 from iAbdulrrahman/feat/libkernel-sys-is-ps4-process

feat(libkernel_sys): implement sceKernelIsPs4Process query

docs/dev/debt/libkernel_sys.md

@@ -368,7 +368,7 @@
 - [sigreturn](../../../core/libs/prx/libkernel_sys/Export.Discovery.cpp) (libkernel_sys) follows FreeBSD 11.4's amd64 [`sys_sigreturn`](https://github.com/freebsd/freebsd-src/blob/8c639945a44588f6cfdddfb057bb5aad88735da0/sys/amd64/amd64/machdep.c#L473-L576) on `setcontext`'s `ucontext_t`: a null context returns `EFAULT`, and `mc_flags` outside `_MC_FLAG_MASK` or an `rflags` differing from the current flags outside `PSL_USERCHANGE` return `EINVAL`; `mc_len` is not checked. As in [`set_fpcontext`](https://github.com/freebsd/freebsd-src/blob/8c639945a44588f6cfdddfb057bb5aad88735da0/sys/amd64/amd64/machdep.c#L2349-L2370), `_MC_FPFMT_NODEV` keeps the FPU state, `_MC_FPOWNED_NONE` loads the initial one, the FPU and PCB owners load `mc_fpstate`, and other values return `EINVAL`. The rest is restored as by `setcontext`, which keeps the `%fs` and `%gs` bases FreeBSD would load. A `%cs` that is not a user selector (FreeBSD also raises `SIGBUS`) and `_MC_HASFPXSTATE` throw
 - [sceKernelGetModuleInfoInternal, sceKernelGetModuleListInternal and sceKernelLoadStartModuleForSysmodule](../../../core/libs/prx/libkernel_sys/Export.cpp) (libkernel_sys) answer for every loaded module, system modules included. `sceKernelGetModuleInfoInternal` fills the 0x1A8-byte `SceKernelModuleInfoEx` of a module handle the way `sceKernelGetModuleInfoFromAddr` does for an address, with [shadPS4's checks](https://github.com/shadps4-emu/shadPS4/blob/a808e76/src/core/libraries/kernel/process.cpp#L243-L258) in their order: `EFAULT` for a null pointer, `EINVAL` when `st_size` is not 0x1A8, `ESRCH` for an unknown handle. `sceKernelGetModuleListInternal` returns the same list as `sceKernelGetModuleList`, as [fpPS4](https://github.com/red-prig/fpPS4/blob/04cefd4/kernel/ps4_libkernel.pas#L852-L858) does; fpPS4 marks that as a guess, and neither is checked on a PS5. `sceKernelLoadStartModuleForSysmodule` forwards to `sceKernelLoadStartModule`
 - [chroot](../../../core/libs/prx/libkernel_sys/Export.cpp) (libkernel_sys) follows FreeBSD 11.4's [`sys_chroot`](https://github.com/freebsd/freebsd-src/blob/8c639945a44588f6cfdddfb057bb5aad88735da0/sys/kern/vfs_syscalls.c#L776-L807) and [`pwd_chroot`](https://github.com/freebsd/freebsd-src/blob/8c639945a44588f6cfdddfb057bb5aad88735da0/sys/kern/kern_descrip.c#L3059-L3085) for a root caller: `EFAULT` for a null path, `ENOENT` for an empty or missing one, `ENAMETOOLONG` for a path of 1024 bytes or more or a component over 255, and `ENOTDIR` for a path that is not a directory or passes through a file. A directory that is the guest root (`/`, `/..`, or `.` after `fchdir` to a descriptor of `/`) succeeds and changes nothing, as the root stays the same directory; the guest is taken never to have changed its root, so open directory descriptors do not make it fail with `EPERM` (`kern.chroot_allow_open_directories` 1). Any other directory throws, naming the path: the guest path resolver has a fixed root and mount aliases (`/app0`, `/savedata0`) that do not move with it. On the console a title starts in a sandbox root, where `pwd_chroot` refuses with `EPERM` while a directory is open; whether that holds for titles, and whether a title holds `PRIV_VFS_CHROOT`, are unverified. Porpoise (PPSA99764) weak-imports it and calls it only as `fchdir` to its saved descriptor of `/` then `chroot(".")`, to put its sandbox root back after a jailbreak daemon replaced it ([`put_root_back`](https://github.com/elripalda/Porpoise-Dolphin-Emulator-for-PS5/blob/2ed1ab5a06995aa198f7bccd4da0f90c3fc29d39/src/porpoise_jailbreak.cpp#L303-L331))
-- [Console identity](../../../core/libs/prx/libkernel_sys/Export.cpp) (libkernel_sys) - `get_authinfo` errors and capability bits remain unverified on PS5; they follow [shadPS4](https://github.com/shadps4-emu/shadPS4/blob/396c2a09a38d22eaa02aab32c1967263dceab95f/src/core/libraries/kernel/kernel.cpp), leaving the authority ID and other capability, attribute and credential words zero. The host models a retail unit (`IsCEX` 1, `IsGenuineCEX` 1, `IsDevKit` 0, `IsGenuineDevKit` 0, `IsTestKit` 0, `IsGenuineTestKit` 0) and reports Prospero architecture (`IsProspero` 1, `IsKratos` 0). The system OpenPSID reuses the ordinary ID; firmware 13.42 reads a separate `machdep.openpsid_for_sys`, whose value is unknown. Null returns positive 22 per the [module report](https://github.com/boykopovar/AnyPS5/pull/10524#issuecomment-6393566914).
+- [Console identity](../../../core/libs/prx/libkernel_sys/Export.cpp) (libkernel_sys) - `get_authinfo` errors and capabilities are unverified on PS5, following [shadPS4](https://github.com/shadps4-emu/shadPS4/blob/396c2a09a38d22eaa02aab32c1967263dceab95f/src/core/libraries/kernel/kernel.cpp) with zero authority and credential words. The host models a retail unit (`IsCEX` 1, `IsGenuineCEX` 1, `IsDevKit` 0, `IsGenuineDevKit` 0, `IsTestKit` 0, `IsGenuineTestKit` 0) and Prospero (`IsProspero` 1, `IsKratos` 0). `sceKernelIsPs4Process` returns 1 when the title ID starts with `CUSA` and 0 otherwise, as `libSceRtc` and `libSceConvertKeycode` tell PS4 titles apart; this mapping follows the PS4 title-ID convention and is unmeasured on a console, since BunnyFl's [13.42 report](https://github.com/boykopovar/AnyPS5/pull/10959#issuecomment-6404011201) only mentions the export returning 0 in passing. System OpenPSID reuses the ordinary ID; firmware 13.42 reads a separate `machdep.openpsid_for_sys` of unknown value. Null returns positive 22 per the [module report](https://github.com/boykopovar/AnyPS5/pull/10524#issuecomment-6393566914).
 - [kldfind, kldfirstmod, kldnext and kldunload](../../../core/libs/prx/libkernel_sys/Export.cpp) (libkernel_sys) follow FreeBSD 11.4's linker calls ([sys/kern/kern_linker.c](https://github.com/freebsd/freebsd-src/blob/release/11.4.0/sys/kern/kern_linker.c)): kldfind validates the module name with CopyPath (EFAULT on null or unreadable pointers, ENAMETOOLONG for paths of 1024 bytes or more) and returns ENOENT for any module name; on FreeBSD the kernel itself is linker file 1, and AnyPS5 models an empty file list, so kldnext(0) returns 0 and kldfind("kernel") fails; kldnext returns ENOENT for negative or positive fileids; kldfirstmod returns ENOENT for any fileid; and kldunload returns EPERM as sandboxed/jailed titles lack PRIV_KLD_UNLOAD. Dynamic kernel linker module lookup and management remain unverified on hardware
 - [kldstat](../../../core/libs/prx/libkernel_sys/Export.cpp) (libkernel_sys) never succeeds: no linker file is listed here, as for `kldnext`, so the kernel's own file (id 1 on FreeBSD) and the modules a console preloads are missing, every file id gets `ENOENT` and the structure is never written. The checks before the lookup follow FreeBSD 11.4's [`sys_kldstat`](https://github.com/freebsd/freebsd-src/blob/releng/11.4/sys/kern/kern_linker.c#L1228-L1250): only the `version` field is read (`EFAULT` when it cannot be), and a version other than the size of `struct kld_file_stat_1` (1056 bytes on amd64) or `struct kld_file_stat` (2080) gets `EINVAL`. Console behaviour is unverified
 - [fchown](../../../core/libs/prx/libkernel_sys/Export.cpp) (libkernel_sys) - ownership is not modelled: the guest's own owner and group (0) and the unchanged value (-1) are accepted, a descriptor that is not open fails with `EBADF`, and any other owner or group throws, naming it. The check reads the descriptor with `fstat`, ignoring the CRT's invalid-parameter handler on Windows as `DescriptorControl` does. The console's ownership rules are unverified. Morrowind (`mshivam019/morrowind-ps5`) imports it