ArrayRef<const char *> ArgsFromMain,
SpecificBumpPtrAllocator<char> &ArgAllocator);
+ // This functions ensures that the standard file descriptors (input, output,
+ // and error) are properly mapped to a file descriptor before we use any of
+ // them. This should only be called by standalone programs, library
+ // components should not call this.
+ static std::error_code FixupStandardFileDescriptors();
+
/// This function determines if the standard input is connected directly
/// to a user's input (keyboard probably), rather than coming from a file
/// or pipe.
#include "llvm/Support/Mutex.h"
#include "llvm/Support/MutexGuard.h"
#include "llvm/Support/TimeValue.h"
+#if HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
return std::error_code();
}
+namespace {
+class FDCloser {
+public:
+ FDCloser(int &FD) : FD(FD), KeepOpen(false) {}
+ void keepOpen() { KeepOpen = true; }
+ ~FDCloser() {
+ if (!KeepOpen && FD >= 0)
+ ::close(FD);
+ }
+
+private:
+ FDCloser(const FDCloser &) LLVM_DELETED_FUNCTION;
+ void operator=(const FDCloser &) LLVM_DELETED_FUNCTION;
+
+ int &FD;
+ bool KeepOpen;
+};
+}
+
+std::error_code Process::FixupStandardFileDescriptors() {
+ int NullFD = -1;
+ FDCloser FDC(NullFD);
+ const int StandardFDs[] = {STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO};
+ for (int StandardFD : StandardFDs) {
+ struct stat st;
+ errno = 0;
+ while (fstat(StandardFD, &st) < 0) {
+ assert(errno && "expected errno to be set if fstat failed!");
+ // fstat should return EBADF if the file descriptor is closed.
+ if (errno == EBADF)
+ break;
+ // retry fstat if we got EINTR, otherwise bubble up the failure.
+ if (errno != EINTR)
+ return std::error_code(errno, std::generic_category());
+ }
+ // if fstat succeeds, move on to the next FD.
+ if (!errno)
+ continue;
+ assert(errno == EBADF && "expected errno to have EBADF at this point!");
+
+ if (NullFD < 0) {
+ while ((NullFD = open("/dev/null", O_RDWR)) < 0) {
+ if (errno == EINTR)
+ continue;
+ return std::error_code(errno, std::generic_category());
+ }
+ }
+
+ if (NullFD == StandardFD)
+ FDC.keepOpen();
+ else if (dup2(NullFD, StandardFD) < 0)
+ return std::error_code(errno, std::generic_category());
+ }
+ return std::error_code();
+}
+
bool Process::StandardInIsUserInput() {
return FileDescriptorIsDisplayed(STDIN_FILENO);
}