FreeBSD: propagate error to user if memory access fails

Previously, an attempt to read an unreadable address reported zeros.
Now, if DoReadMemory or DoWriteMemory encounters error then return 0
(bytes read or written) so that the error is reported to the user.

llvm.org/pr37190

llvm-svn: 330500

1 files changed, 6 insertions, 2 deletions

diff --git a/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp b/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp
index 839fc33c8d9..feba3af8fcf 100644
--- a/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp
+++ b/lldb/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp
@@ -159,8 +159,10 @@ static size_t DoReadMemory(lldb::pid_t pid, lldb::addr_t vm_addr, void *buf,
   pi_desc.piod_addr = buf;
   pi_desc.piod_len = size;
 
-  if (PTRACE(PT_IO, pid, (caddr_t)&pi_desc, 0) < 0)
+  if (PTRACE(PT_IO, pid, (caddr_t)&pi_desc, 0) < 0) {
     error.SetErrorToErrno();
+    return 0;
+  }
   return pi_desc.piod_len;
 }
 
@@ -173,8 +175,10 @@ static size_t DoWriteMemory(lldb::pid_t pid, lldb::addr_t vm_addr,
   pi_desc.piod_addr = (void *)buf;
   pi_desc.piod_len = size;
 
-  if (PTRACE(PT_IO, pid, (caddr_t)&pi_desc, 0) < 0)
+  if (PTRACE(PT_IO, pid, (caddr_t)&pi_desc, 0) < 0) {
     error.SetErrorToErrno();
+    return 0;
+  }
   return pi_desc.piod_len;
 }