Add an ExecuteNoWait interface to support asynchronous process spawning.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75055 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/System/Unix/Program.inc b/lib/System/Unix/Program.inc
index cdc6fee..7e196b0 100644
--- a/lib/System/Unix/Program.inc
+++ b/lib/System/Unix/Program.inc
@@ -274,6 +274,78 @@
}
+void
+Program::ExecuteNoWait(const Path& path,
+ const char** args,
+ const char** envp,
+ const Path** redirects,
+ unsigned memoryLimit,
+ std::string* ErrMsg)
+{
+ if (!path.canExecute()) {
+ if (ErrMsg)
+ *ErrMsg = path.toString() + " is not executable";
+ return;
+ }
+
+ // Create a child process.
+ int child = fork();
+ switch (child) {
+ // An error occured: Return to the caller.
+ case -1:
+ MakeErrMsg(ErrMsg, "Couldn't fork");
+ return;
+
+ // Child process: Execute the program.
+ case 0: {
+ // Redirect file descriptors...
+ if (redirects) {
+ // Redirect stdin
+ if (RedirectIO(redirects[0], 0, ErrMsg)) { return; }
+ // Redirect stdout
+ if (RedirectIO(redirects[1], 1, ErrMsg)) { return; }
+ if (redirects[1] && redirects[2] &&
+ *(redirects[1]) == *(redirects[2])) {
+ // If stdout and stderr should go to the same place, redirect stderr
+ // to the FD already open for stdout.
+ if (-1 == dup2(1,2)) {
+ MakeErrMsg(ErrMsg, "Can't redirect stderr to stdout");
+ return;
+ }
+ } else {
+ // Just redirect stderr
+ if (RedirectIO(redirects[2], 2, ErrMsg)) { return; }
+ }
+ }
+
+ // Set memory limits
+ if (memoryLimit!=0) {
+ SetMemoryLimits(memoryLimit);
+ }
+
+ // Execute!
+ if (envp != 0)
+ execve (path.c_str(), (char**)args, (char**)envp);
+ else
+ execv (path.c_str(), (char**)args);
+ // If the execve() failed, we should exit and let the parent pick up
+ // our non-zero exit status.
+ exit (errno);
+ }
+
+ // Parent process: Break out of the switch to do our processing.
+ default:
+ break;
+ }
+
+ // Make sure stderr and stdout have been flushed
+ std::cerr << std::flush;
+ std::cout << std::flush;
+ fsync(1);
+ fsync(2);
+
+}
+
bool Program::ChangeStdinToBinary(){
// Do nothing, as Unix doesn't differentiate between text and binary.
return false;