Custom libc wrapper: added fork function

src/clibwrap/fork.rs

@@ -0,0 +1,26 @@
+use crate::clibwrap::{ErrnoError, Pid};
+
+mod external {
+	use crate::clibwrap::Pid;
+
+	unsafe extern "C" {
+		pub fn fork() -> Pid;
+	}
+}
+
+#[derive(Debug)]
+pub enum ForkResult {
+	Parent { child_pid: Pid },
+	Child,
+}
+
+pub unsafe fn fork() -> Result<ForkResult, ErrnoError> {
+	let return_value = unsafe { external::fork() };
+	if return_value == -1 {
+		unsafe { Err(ErrnoError::from_current_errno()) }
+	} else if return_value == 0 {
+		Ok(ForkResult::Child)
+	} else {
+		Ok(ForkResult::Parent { child_pid: return_value })
+	}
+}

src/clibwrap/mod.rs

@@ -1,7 +1,8 @@
 use std::ffi::{c_char, c_int, CStr};
 pub mod ptrace;
+pub mod fork;
 
-type Pid = i32;
+pub type Pid = i32;
 
 unsafe extern "C" {
 	fn __errno_location() -> *mut c_int;

src/main.rs

@@ -3,9 +3,10 @@ mod syscall_info;
 mod clibwrap;
 
 use crate::debug_target::{ExitedTarget, StoppedTarget};
+use clibwrap::fork::{fork, ForkResult};
 use color_eyre::eyre::eyre;
 use either::Either;
-use nix::unistd::{fork, ForkResult};
+use nix::unistd::Pid;
 use std::ffi::CString;
 
 #[allow(dead_code)]
@@ -52,10 +53,10 @@ fn main() -> color_eyre::Result<()> {
 			nix::unistd::execv(&child_exec_path, &[&child_exec_path])?;
 			unreachable!();
 		}
-		Ok(ForkResult::Parent { child: child_pid }) => {
+		Ok(ForkResult::Parent { child_pid }) => {
 			println!("✔️ Created child {child_pid}");
 
-			let mut target = StoppedTarget::new(child_pid)?;
+			let mut target = StoppedTarget::new(Pid::from_raw(child_pid))?;
 			println!("✔️ Child ready!");
 
 			let breakpoint1 = 0x40101b;