Initial project import

tools/v/vlib/os/debugger_linux.c.v

@@ -0,0 +1,45 @@
+module os
+
+#include <sys/ptrace.h>
+
+fn C.ptrace(u32, u32, voidptr, voidptr) u64
+
+// debugger_present returns a bool indicating if the process is being debugged.
+pub fn debugger_present() bool {
+	$if cross ? {
+		return false
+	}
+	$if !cross ? {
+		$if linux {
+			// check if a child process could trace its parent process,
+			// if not a debugger must be present
+			pid := fork()
+			if pid == 0 {
+				ppid := getppid()
+				if C.ptrace(C.PTRACE_ATTACH, ppid, 0, 0) == 0 {
+					C.waitpid(ppid, 0, 0)
+
+					// detach ptrace, otherwise further checks would indicate a debugger is present (ptrace is the Debugger then)
+					C.ptrace(C.PTRACE_DETACH, ppid, 0, 0)
+
+					// no external debugger
+					exit(0)
+				} else {
+					// an error occurred, a external debugger must be present
+					exit(1)
+				}
+			} else {
+				mut status := 0
+				// wait until the child process dies
+				C.waitpid(pid, &status, 0)
+				// check the exit code of the child process check
+				if posix_wait_status_exit_code(status) == 0 {
+					return false
+				} else {
+					return true
+				}
+			}
+		}
+	}
+	return false
+}