48 lines
1.2 KiB
C++
48 lines
1.2 KiB
C++
/*
|
|
* Copyright (c) 2020, Itamar S. <itamar8910@gmail.com>
|
|
*
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*/
|
|
|
|
#include <errno.h>
|
|
#include <sys/ptrace.h>
|
|
#include <syscall.h>
|
|
|
|
extern "C" {
|
|
|
|
int ptrace(int request, pid_t tid, void* addr, int data)
|
|
{
|
|
// PT_PEEK needs special handling since the syscall wrapper
|
|
// returns the peeked value as an int, which can be negative because of the cast.
|
|
// When using PT_PEEK, the user can check if an error occurred
|
|
// by looking at errno rather than the return value.
|
|
|
|
u32 out_data;
|
|
Syscall::SC_ptrace_peek_params peek_params;
|
|
auto is_peek_type = request == PT_PEEK || request == PT_PEEKDEBUG;
|
|
if (is_peek_type) {
|
|
peek_params.address = reinterpret_cast<u32*>(addr);
|
|
peek_params.out_data = &out_data;
|
|
addr = &peek_params;
|
|
}
|
|
|
|
Syscall::SC_ptrace_params params {
|
|
request,
|
|
tid,
|
|
reinterpret_cast<u8*>(addr),
|
|
data
|
|
};
|
|
int rc = syscall(SC_ptrace, ¶ms);
|
|
|
|
if (is_peek_type) {
|
|
if (rc < 0) {
|
|
errno = -rc;
|
|
return -1;
|
|
}
|
|
errno = 0;
|
|
return static_cast<int>(out_data);
|
|
}
|
|
|
|
__RETURN_WITH_ERRNO(rc, rc, -1);
|
|
}
|
|
}
|