From 8e87d340c310c1ce4893cc5517d33aaf848eb808 Mon Sep 17 00:00:00 2001
From: Itamar <itamar8910@gmail.com>
Date: Sat, 11 Apr 2020 16:38:59 +0300
Subject: [PATCH] strace: Update ptrace() usage

ptrace with PT_TRACEME was updated to also stop the traced thread on
exit from execve.
---
 Userland/strace.cpp | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/Userland/strace.cpp b/Userland/strace.cpp
index 30d7bad9b7..b6687cfa58 100644
--- a/Userland/strace.cpp
+++ b/Userland/strace.cpp
@@ -60,11 +60,14 @@ int main(int argc, char** argv)
     if (argc == 1)
         return usage();
 
+    bool spawned_new_process = false;
+
     if (!strcmp(argv[1], "-p")) {
         if (argc != 3)
             return usage();
         g_pid = atoi(argv[2]);
     } else {
+        spawned_new_process = true;
         int pid = fork();
         if (!pid) {
             if (ptrace(PT_TRACE_ME, 0, 0, 0) == -1) {
@@ -100,6 +103,18 @@ int main(int argc, char** argv)
         return 1;
     }
 
+    if (spawned_new_process) {
+
+        if (ptrace(PT_CONTINUE, g_pid, 0, 0) < 0) {
+            perror("continue");
+            return 1;
+        }
+        if (waitpid(g_pid, nullptr, WSTOPPED) != g_pid) {
+            perror("wait_pid");
+            return 1;
+        }
+    }
+
     for (;;) {
         if (ptrace(PT_SYSCALL, g_pid, 0, 0) == -1) {
             if (errno == ESRCH)