| use alloc::string::String; |
| use core::mem::transmute; |
| use core::panic::BoxMeUp; |
| use core::ptr::copy_nonoverlapping; |
| |
| const ANDROID_SET_ABORT_MESSAGE: &[u8] = b"android_set_abort_message\0"; |
| type SetAbortMessageType = unsafe extern "C" fn(*const libc::c_char) -> (); |
| |
| // Forward the abort message to libc's android_set_abort_message. We try our best to populate the |
| // message but as this function may already be called as part of a failed allocation, it might not be |
| // possible to do so. |
| // |
| // Some methods of core are on purpose avoided (such as try_reserve) as these rely on the correct |
| // resolution of rust_eh_personality which is loosely defined in panic_abort. |
| // |
| // Weakly resolve the symbol for android_set_abort_message. This function is only available |
| // for API >= 21. |
| pub(crate) unsafe fn android_set_abort_message(payload: *mut &mut dyn BoxMeUp) { |
| let func_addr = |
| libc::dlsym(libc::RTLD_DEFAULT, ANDROID_SET_ABORT_MESSAGE.as_ptr() as *const libc::c_char) |
| as usize; |
| if func_addr == 0 { |
| return; |
| } |
| |
| let payload = (*payload).get(); |
| let msg = match payload.downcast_ref::<&'static str>() { |
| Some(msg) => msg.as_bytes(), |
| None => match payload.downcast_ref::<String>() { |
| Some(msg) => msg.as_bytes(), |
| None => &[], |
| }, |
| }; |
| if msg.is_empty() { |
| return; |
| } |
| |
| // Allocate a new buffer to append the null byte. |
| let size = msg.len() + 1usize; |
| let buf = libc::malloc(size) as *mut libc::c_char; |
| if buf.is_null() { |
| return; // allocation failure |
| } |
| copy_nonoverlapping(msg.as_ptr(), buf as *mut u8, msg.len()); |
| buf.add(msg.len()).write(0); |
| |
| let func = transmute::<usize, SetAbortMessageType>(func_addr); |
| func(buf); |
| } |