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Diffstat (limited to 'libs/pbd/msvc/msvc_poll.cc')
| -rw-r--r-- | libs/pbd/msvc/msvc_poll.cc | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/libs/pbd/msvc/msvc_poll.cc b/libs/pbd/msvc/msvc_poll.cc new file mode 100644 index 0000000000..e12ef2bbef --- /dev/null +++ b/libs/pbd/msvc/msvc_poll.cc @@ -0,0 +1,215 @@ +/* + Copyright (C) 2009 John Emmas + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + +*/ + +#ifdef COMPILER_MSVC + +//#include <glib/gtimer.h> +#include "pbd/msvc_pbd.h" + +#ifndef _DWORD_DEFINED +#define _DWORD_DEFINED +typedef unsigned long DWORD; +#endif // !_DWORD_DEFINED + +/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * + * * + * Note that this entire strategy failed to work, at least for pipes. It turned * + * out that Windows 'tell()' always returns 0 when used on a pipe. This strategy * + * is now deprecated, having been replaced by a new pipe-like object, which I've * + * called 'PBD::pipex'. This polling functionality is included here mostly so * + * that Ardour will build and launch under Windows. However, any module that * + * relies on polling a pipe will eventually need to use the new pipex object. * + * This code will allow it to compile and link successfully, although it won't * + * poll successfully at run time. Having said that, these functions might well * + * work for ports and/or other machanisms that get represented by a file handle. * + * * + * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ + +int poll_input (struct pollfd *fds, nfds_t nfds, int& elapsed_time, int timeout) +{ +DWORD dwOldTickCount, + dwNewTickCount = GetTickCount(); +bool input = false, + error = false; +int ret = 0; + + if (NULL != fds) + { + nfds_t loop; + short ev_mask = (POLLOUT|POLLWRNORM|POLLWRBAND); + + errno = NO_ERROR; + + do + { + dwOldTickCount = dwNewTickCount; + + for (loop=0; loop<nfds; loop++) + fds[loop].revents = 0; + + for (loop=0; (loop<nfds && !error); loop++) + { + if (!(fds[loop].events & ev_mask)) + { + long pos = _tell(fds[loop].fd); + + if (0 > pos) + { + // An error occured ('errno' should have been set by '_tell()') + ret = (-1); + fds[loop].revents = POLLERR; + if (fds[loop].events & POLLRDNORM) + fds[loop].revents |= POLLRDNORM; + if (fds[loop].events & POLLRDBAND) + fds[loop].revents |= POLLRDBAND; + if (fds[loop].events & POLLPRI) + fds[loop].revents |= POLLPRI; + + // Do we want to abort on error? + if (fds[loop].events & POLLERR) + error = true; + } + else if (pos > 0) + { + // Input characters were found for this fd + ret += 1; + if (fds[loop].events & POLLRDNORM) + fds[loop].revents |= POLLRDNORM; + if (fds[loop].events & POLLRDBAND) + fds[loop].revents |= POLLRDBAND; + if (fds[loop].events & POLLPRI) + fds[loop].revents |= POLLPRI; + + // Do we want to abort on input? + if ((fds[loop].events & POLLIN) || + (fds[loop].events & POLLPRI) || + (fds[loop].events & POLLRDNORM) || + (fds[loop].events & POLLRDBAND)) + input = true; + } + } + } + + if (input) + break; + + dwNewTickCount = GetTickCount(); + elapsed_time += (dwNewTickCount-dwOldTickCount); + // Note that the above will wrap round if the user leaves + // his computer powered up for more than about 50 days! + + // Sleep briefly because GetTickCount() only has an accuracy of 10mS + Sleep(10); // For some reason 'g_usleep()' craps over everything here. Different 'C' runtimes??? + + } while ((!error) && ((timeout == (-1)) || (elapsed_time < timeout))); + } + else + { + errno = ERROR_BAD_ARGUMENTS; + ret = (-1); + } + + return (ret); +} + +int poll_output (struct pollfd *fds, nfds_t nfds, int& elapsed_time, int timeout) +{ +int ret = 0; // This functionality is not yet implemented + + if (NULL != fds) + { + // Just flag whichever pollfd was specified for writing + short ev_mask = (POLLOUT|POLLWRNORM|POLLWRBAND); + + errno = NO_ERROR; + elapsed_time = 0; + + for (nfds_t loop=0; loop<nfds; loop++) + { + if (fds[loop].events & ev_mask) + { + fds[loop].revents = POLLNVAL; + errno = ERROR_INVALID_ACCESS; + ret = (-1); + } + } + } + else + { + errno = ERROR_BAD_ARGUMENTS; + ret = (-1); + } + + return (ret); +} + +//*************************************************************** +// +// poll() +// +// Emulates POSIX poll() using Win32 _tell(). +// +// Returns: +// +// On Success: A positive integer indicating the total number +// of file descriptors that were available for +// writing or had data available for reading. +// On Failure: -1 (the actual error is saved in 'errno'). +// +PBD_API int PBD_APICALLTYPE +poll (struct pollfd *fds, nfds_t nfds, int timeout) +{ +int elapsed_time = 0; +int ret = (-1); + + // Note that this functionality is not fully implemented. + // At the time of writing, Ardour seems only to poll on + // read pipes. Therefore return an error if any write + // pipe seems to have been specified or if too many file + // descriptors were passed. + short ev_mask = (POLLOUT|POLLWRNORM|POLLWRBAND); + + if ((nfds > OPEN_MAX) || (nfds > NPOLLFILE)) + { + errno = ERROR_TOO_MANY_OPEN_FILES; + } + else + { + ret = 0; + + for (nfds_t loop=0; loop<nfds; loop++) + { + if (fds[loop].events & ev_mask) + { + ret = poll_output(fds, nfds, elapsed_time, timeout); + break; + } + } + + if (0 == ret) + { + // Poll for input + ret = poll_input(fds, nfds, elapsed_time, timeout); + } + } + + return (ret); +} + +#endif //COMPILER_MSVC |