Bugfix communication by keeping original input pipe in parent process

Prior to this commit, communication sent to the solver was not being
received. Sending the data was reported as successful, but the
subprocess could not read it from the standard input.

The inherit flag is now set rather than cleared, so that the sub
process is able to use the handle.

This commit enables all piped_process unit tests on Windows, as these
now work/pass.

Author: thomasspriggs

src/util/piped_process.cpp

@@ -138,9 +138,9 @@ piped_processt::piped_processt(const std::vector<std::string> &commandvec)
   // Use process ID as a unique ID for this process at this time.
   base_name.append(std::to_string(GetCurrentProcessId()));
   const std::string in_name = base_name + "\\IN";
-  child_std_IN_Rd = CreateNamedPipe(
+  child_std_IN_Wr = CreateNamedPipe(
     in_name.c_str(),
-    PIPE_ACCESS_INBOUND,          // Reading for us
+    PIPE_ACCESS_OUTBOUND,         // Writing for us
     PIPE_TYPE_BYTE | PIPE_NOWAIT, // Bytes and non-blocking
     PIPE_UNLIMITED_INSTANCES,     // Probably doesn't matter
     BUFSIZE,
@@ -156,9 +156,9 @@ piped_processt::piped_processt(const std::vector<std::string> &commandvec)
     throw system_exceptiont("Input pipe creation failed for child_std_IN_Rd");
   }
   // Connect to the other side of the pipe
-  child_std_IN_Wr = CreateFile(
+  child_std_IN_Rd = CreateFile(
     in_name.c_str(),
-    GENERIC_WRITE,                                  // Write side
+    GENERIC_READ,                                   // Read side
     FILE_SHARE_READ | FILE_SHARE_WRITE,             // Shared read/write
     &sec_attr,                                      // Need this for inherit
     OPEN_EXISTING,                                  // Opening other end
@@ -168,7 +168,8 @@ piped_processt::piped_processt(const std::vector<std::string> &commandvec)
   {
     throw system_exceptiont("Input pipe creation failed for child_std_IN_Wr");
   }
-  if(!SetHandleInformation(child_std_IN_Rd, HANDLE_FLAG_INHERIT, 0))
+  if(!SetHandleInformation(
+       child_std_IN_Rd, HANDLE_FLAG_INHERIT, HANDLE_FLAG_INHERIT))
   {
     throw system_exceptiont(
       "Input pipe creation failed on SetHandleInformation");

unit/util/piped_process.cpp

@@ -107,8 +107,6 @@ TEST_CASE(
   REQUIRE(calc < 2);
 }
 
-#ifndef _WIN32
-// No Windows tests for z3 due to path and dependency issues.
 TEST_CASE(
   "Creating a sub process of z3 and read a response from an echo command.",
   "[core][util][piped_process][.z3]")
@@ -314,4 +312,3 @@ TEST_CASE(
   REQUIRE(
     process.send("(exit)\n") == piped_processt::send_responset::SUCCEEDED);
 }
-#endif