WIP android64 support #12
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| // nix currently doesn't support PTRACE_GETFPREGS, so we have to do it ourselves | ||
| fn getfpregs(pid: Pid) -> Result<libc_user_fpsimd_struct> { | ||
| Self::ptrace_get_data::<libc_user_fpsimd_struct>( | ||
| ptrace::Request::PTRACE_GETFPREGS, |
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I've almost got everything reasonable and compiling, but the last remaining blocker is this code here, where we get each thread's registers with ptrace-based register lookup.
For whatever reason it appears that PTRACE_GETREGS and PTRACE_GETFPREGS just don't exist on aarch64 (android?). The docs note that the APIs don't exist on all platforms but it is just Weird that this was the platform to do it?
Not fully clear on what's up with the breakpad version, ifdef hell...
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Possible I want PTRACE_GETREGSET, but the nix ptrace stuff also doesn't have that for android. Not clear if that's a bug tho.
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I fear, I have not much to add here. I'm most certainly not an Android expert :-/
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Just so you don't get frustrated waiting: You caught me on my first vacation day :-) I'll be back next week Wed. and will take a look then.
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Yeah no problem. I went down a really deep rabbit-hole on the whole u128 issue, and I am happy to report that I've demonstrated that u128/i128 are actually totally sound for FFI on exactly aarch64 (android AND macos)! |
| @@ -37,7 +38,8 @@ pub mod imp; | |||
| pub mod imp; | |||
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| #[cfg(target_arch = "aarch64")] | |||
| pub type fpstate_t = libc::fpsimd_context; // Currently not part of libc! This will produce an error. | |||
| #[allow(non_camel_case_types)] | |||
| pub type fpstate_t = libc_user_fpsimd_struct; // Currently not part of libc! This will produce an error. | |||
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Since you created your own struct, this will not produce an error anymore? So the second half of the comment can be removed, I think.
| // nix currently doesn't support PTRACE_GETFPREGS, so we have to do it ourselves | ||
| fn getfpregs(pid: Pid) -> Result<libc_user_fpsimd_struct> { | ||
| Self::ptrace_get_data::<libc_user_fpsimd_struct>( | ||
| ptrace::Request::PTRACE_GETFPREGS, |
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I fear, I have not much to add here. I'm most certainly not an Android expert :-/
| pub struct layout_only_ffi_u128(u128); | ||
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| impl layout_only_ffi_u128 { | ||
| pub fn to_ne_bytes(self) -> [u8; 16] { |
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Where is this function used?
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Slowly yak-shaving... nix-rust/nix#1679 |
Breakpad vendors a copy of Google's linux-syscall-support header, which provides C shims for calling Linux syscalls directly, FYI: That being said, it looks like |
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Closing this as PR #81 should give us everything we need |
This isn't done yet but I'm submitting this as a PR so that I can iterate on this in a place where the code is visible, and discuss the issues I'm running into.
Some temp garbage is in here as I try a few different things out.