// establish a connection to the specified pipe and returns its handle
// static
HANDLE Client::connectPipe(const wchar_t* pipeName) {
bool hasErrors = false;
HANDLE pipe = INVALID_HANDLE_VALUE;
for (;;) {
pipe = CreateFile(pipeName, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL);
if (pipe != INVALID_HANDLE_VALUE) {
// the pipe is successfully created
// security check: make sure that we're connecting to the correct server
ULONG serverPid;
if (GetNamedPipeServerProcessId(pipe, &serverPid)) {
// FIXME: check the command line of the server?
// See this: http://www.codeproject.com/Articles/19685/Get-Process-Info-with-NtQueryInformationProcess
// Too bad! Undocumented Windows internal API might be needed here. :-(
}
break;
}
// being busy is not really an error since we just need to wait.
if (GetLastError() != ERROR_PIPE_BUSY) {
hasErrors = true; // otherwise, pipe creation fails
break;
}
// All pipe instances are busy, so wait for 2 seconds.
if (!WaitNamedPipe(pipeName, 2000)) {
hasErrors = true;
break;
}
}
if (!hasErrors) {
// The pipe is connected; change to message-read mode.
DWORD mode = PIPE_READMODE_MESSAGE;
if (!SetNamedPipeHandleState(pipe, &mode, NULL, NULL)) {
hasErrors = true;
}
}
// the pipe is created, but errors happened, destroy it.
if (hasErrors && pipe != INVALID_HANDLE_VALUE) {
DisconnectNamedPipe(pipe);
CloseHandle(pipe);
pipe = INVALID_HANDLE_VALUE;
}
return pipe;
}
int main(int argc, char **argv)
{
char result = 0;
int err = 0;
struct stat st;
#ifdef _WIN32
HANDLE fds[3];
ULONG pid;
HANDLE hProcess, hServerProcess;
DWORD dwNumberOfBytesRead;
CHAR argv0[PATHSZ];
GetModuleFileName(NULL, argv0, PATHSZ);
compute_merlinpath(merlin_path, argv0, &st);
#else
compute_merlinpath(merlin_path, argv[0], &st);
#endif
if (argc >= 2 && strcmp(argv[1], "server") == 0)
{
IPC_SOCKET_TYPE sock;
ssize_t len;
#ifdef _WIN32
compute_socketname(socketname, eventname, merlin_path);
#else
compute_socketname(socketname, &st);
#endif
sock = connect_and_serve(socketname, eventname, merlin_path);
len = prepare_args(argbuffer, sizeof(argbuffer), argc-2, argv+2);
#ifdef _WIN32
hProcess = GetCurrentProcess();
if (!GetNamedPipeServerProcessId(sock, &pid))
failwith_perror("GetNamedPipeServerProcessId");
hServerProcess = OpenProcess(PROCESS_DUP_HANDLE, FALSE, pid);
if (hServerProcess == INVALID_HANDLE_VALUE)
failwith_perror("OpenProcess");
if (!DuplicateHandle(hProcess, GetStdHandle(STD_INPUT_HANDLE), hServerProcess, &fds[0], 0, FALSE, DUPLICATE_SAME_ACCESS))
failwith_perror("DuplicateHandle(stdin)");
if (!DuplicateHandle(hProcess, GetStdHandle(STD_OUTPUT_HANDLE), hServerProcess, &fds[1], 0, FALSE, DUPLICATE_SAME_ACCESS))
failwith_perror("DuplicateHandle(stdout)");
CloseHandle(GetStdHandle(STD_OUTPUT_HANDLE));
if (!DuplicateHandle(hProcess, GetStdHandle(STD_ERROR_HANDLE), hServerProcess, &fds[2], 0, FALSE, DUPLICATE_SAME_ACCESS))
failwith_perror("DuplicateHandle(stderr)");
#else
int fds[3] = { STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO };
#endif
ipc_send(sock, argbuffer, len, fds);
#ifdef _WIN32
if (ReadFile(sock, &result, 1, &dwNumberOfBytesRead, NULL) && dwNumberOfBytesRead == 1)
err = 1;
#else
NO_EINTR(err, read(sock, &result, 1));
#endif
if (err == 1)
exit(result);
unexpected_termination(argc, argv);
}
else
{
argv[0] = ocamlmerlin_server;
execvp(merlin_path, argv);
failwith_perror("execvp(ocamlmerlin-server)");
}
}
