Modernize and clean-up the Predicate class

Summary:
The comments on this class were out of date with the implementation, and
the implementation itself was inconsistent with our usage of the Timeout
class (I started converting everything to use this class back in D27136,
but I missed this one). I avoid duplicating the waiting logic by
introducing a templated WaitFor function, and make other functions
delegate to that. This function can be also used as a replacement for
the unused WaitForBitToBeSet functions I removed, if it turns out to be
necessary.

As this changes the meaning of a "zero" timeout, I tracked down all the
callers of these functions and updated them accordingly. Propagating the
changes to all the callers of RunShellCommand was a bit too much for
this patch, so I stopped there and will continue that in a follow-up
patch.

I also add some basic unittests for the functions I modified.

Reviewers: jingham, clayborg

Subscribers: mgorny, lldb-commits

Differential Revision: https://reviews.llvm.org/D46580

llvm-svn: 331880

2 files changed, 9 insertions, 10 deletions

diff --git a/lldb/source/Host/common/Host.cpp b/lldb/source/Host/common/Host.cpp
index 49f1f045aab..becd914650b 100644
--- a/lldb/source/Host/common/Host.cpp
+++ b/lldb/source/Host/common/Host.cpp
@@ -536,8 +536,11 @@ Status Host::RunShellCommand(const Args &args, const FileSpec &working_dir,
     error.SetErrorString("failed to get process ID");
 
   if (error.Success()) {
-    if (!shell_info_sp->process_reaped.WaitForValueEqualTo(
-            true, std::chrono::seconds(timeout_sec))) {
+    // TODO: Remove this and make the function take Timeout<> argument.
+    Timeout<std::micro> timeout(llvm::None);
+    if (timeout_sec != 0)
+      timeout = std::chrono::seconds(timeout_sec);
+    if (!shell_info_sp->process_reaped.WaitForValueEqualTo(true, timeout)) {
       error.SetErrorString("timed out waiting for shell command to complete");
 
       // Kill the process since it didn't complete within the timeout specified
diff --git a/lldb/source/Host/posix/ConnectionFileDescriptorPosix.cpp b/lldb/source/Host/posix/ConnectionFileDescriptorPosix.cpp
index 2671dbbb65d..c21bb786a89 100644
--- a/lldb/source/Host/posix/ConnectionFileDescriptorPosix.cpp
+++ b/lldb/source/Host/posix/ConnectionFileDescriptorPosix.cpp
@@ -746,14 +746,10 @@ ConnectionStatus ConnectionFileDescriptor::ConnectUDP(llvm::StringRef s,
   return eConnectionStatusSuccess;
 }
 
-uint16_t ConnectionFileDescriptor::GetListeningPort(uint32_t timeout_sec) {
-  uint16_t bound_port = 0;
-  if (timeout_sec == UINT32_MAX)
-    m_port_predicate.WaitForValueNotEqualTo(0, bound_port);
-  else
-    m_port_predicate.WaitForValueNotEqualTo(0, bound_port,
-                                            std::chrono::seconds(timeout_sec));
-  return bound_port;
+uint16_t
+ConnectionFileDescriptor::GetListeningPort(const Timeout<std::micro> &timeout) {
+  auto Result = m_port_predicate.WaitForValueNotEqualTo(0, timeout);
+  return Result ? *Result : 0;
 }
 
 bool ConnectionFileDescriptor::GetChildProcessesInherit() const {