make stdio open, read, and write operations cancellation points

[oweals/musl.git] / src / misc / ptrace.c

diff --git a/src/misc/ptrace.c b/src/misc/ptrace.c
index 1cc00167331c83639230cb6484e9dede5f299f41..f8540698b47277ecc3448fd9e98e8d1bd152f8bc 100644 (file)
--- a/src/misc/ptrace.c
+++ b/src/misc/ptrace.c
@@ -8,11 +8,18 @@ long ptrace(int req, ...)
        va_list ap;
        pid_t pid;
        void *addr, *data, *addr2;
+       long ret, result;
+
        va_start(ap, req);
        pid = va_arg(ap, pid_t);
        addr = va_arg(ap, void *);
        data = va_arg(ap, void *);
        addr2 = va_arg(ap, void *);
        va_end(ap);
-       return syscall(SYS_ptrace, req, pid, addr, data, addr2);
+
+       if (req<4U) data = &result;
+       ret = syscall(SYS_ptrace, req, pid, addr, data, addr2);
+
+       if (ret<0 || req>=4U) return ret;
+       return result;
 }