common: Windows 'spawn' support for tx and block notifications

src/common/spawn.cpp

@@ -0,0 +1,141 @@
+// Copyright (c) 2018, The Monero Project
+// 
+// All rights reserved.
+// 
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+// 
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+// 
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+// 
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+// 
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include <errno.h>
+#include <unistd.h>
+#include <sys/types.h>
+#ifdef _WIN32
+#include <boost/algorithm/string/join.hpp>
+#include <boost/scope_exit.hpp>
+#include <windows.h>
+#else
+#include <sys/wait.h>
+#endif
+
+#include "misc_log_ex.h"
+#include "spawn.h"
+
+namespace tools
+{
+
+int spawn(const char *filename, const std::vector<std::string>& args, bool wait)
+{
+#ifdef _WIN32
+  std::string joined = boost::algorithm::join(args, " ");
+  char *commandLine = !joined.empty() ? &joined[0] : nullptr;
+  STARTUPINFOA si = {};
+  si.cb = sizeof(si);
+  PROCESS_INFORMATION pi;
+  if (!CreateProcessA(filename, commandLine, nullptr, nullptr, false, 0, nullptr, nullptr, &si, &pi))
+  {
+    MERROR("CreateProcess failed. Error code " << GetLastError());
+    return -1;
+  }
+  
+  BOOST_SCOPE_EXIT(&pi)
+  {
+    CloseHandle(pi.hThread);
+    CloseHandle(pi.hProcess);
+  }
+  BOOST_SCOPE_EXIT_END
+
+  if (!wait)
+  {
+    return 0;
+  }
+
+  DWORD result = WaitForSingleObject(pi.hProcess, INFINITE);
+  if (result != WAIT_OBJECT_0)
+  {
+    MERROR("WaitForSingleObject failed. Result " << result << ", error code " << GetLastError());
+    return -1;
+  }
+
+  DWORD exitCode;
+  if (!GetExitCodeProcess(pi.hProcess, &exitCode))
+  {
+    MERROR("GetExitCodeProcess failed. Error code " << GetLastError());
+    return -1;
+  }
+
+  MINFO("Child exited with " << exitCode);
+  return static_cast<int>(exitCode);
+#else
+  char **argv = (char**)alloca(sizeof(char*) * (args.size() + 1));
+  for (size_t n = 0; n < args.size(); ++n)
+    argv[n] = (char*)args[n].c_str();
+  argv[args.size()] = NULL;
+
+  pid_t pid = fork();
+  if (pid < 0)
+  {
+    MERROR("Error forking: " << strerror(errno));
+    return -1;
+  }
+
+  // child
+  if (pid == 0)
+  {
+    char *envp[] = {NULL};
+    execve(filename, argv, envp);
+    MERROR("Failed to execve: " << strerror(errno));
+    return -1;
+  }
+
+  // parent
+  if (pid > 0)
+  {
+    if (!wait)
+      return 0;
+
+    while (1)
+    {
+      int wstatus = 0;
+      pid_t w = waitpid(pid, &wstatus, WUNTRACED | WCONTINUED);
+      if (w  < 0) {
+        MERROR("Error waiting for child: " << strerror(errno));
+        return -1;
+      }
+      if (WIFEXITED(wstatus))
+      {
+        MINFO("Child exited with " << WEXITSTATUS(wstatus));
+        return WEXITSTATUS(wstatus);
+      }
+      if (WIFSIGNALED(wstatus))
+      {
+        MINFO("Child killed by " << WEXITSTATUS(wstatus));
+        return WEXITSTATUS(wstatus);
+      }
+    }
+  }
+  MERROR("Secret passage found");
+  return -1;
+#endif
+}
+
+}