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Diffstat (limited to 'vendor/github.com/karalabe/hid/libusb/libusb/os/poll_windows.c')
-rw-r--r--vendor/github.com/karalabe/hid/libusb/libusb/os/poll_windows.c728
1 files changed, 0 insertions, 728 deletions
diff --git a/vendor/github.com/karalabe/hid/libusb/libusb/os/poll_windows.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/poll_windows.c
deleted file mode 100644
index 9825607..0000000
--- a/vendor/github.com/karalabe/hid/libusb/libusb/os/poll_windows.c
+++ /dev/null
@@ -1,728 +0,0 @@
-/*
- * poll_windows: poll compatibility wrapper for Windows
- * Copyright © 2012-2013 RealVNC Ltd.
- * Copyright © 2009-2010 Pete Batard <pete@akeo.ie>
- * With contributions from Michael Plante, Orin Eman et al.
- * Parts of poll implementation from libusb-win32, by Stephan Meyer et al.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library 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
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- *
- */
-
-/*
- * poll() and pipe() Windows compatibility layer for libusb 1.0
- *
- * The way this layer works is by using OVERLAPPED with async I/O transfers, as
- * OVERLAPPED have an associated event which is flagged for I/O completion.
- *
- * For USB pollable async I/O, you would typically:
- * - obtain a Windows HANDLE to a file or device that has been opened in
- * OVERLAPPED mode
- * - call usbi_create_fd with this handle to obtain a custom fd.
- * Note that if you need simultaneous R/W access, you need to call create_fd
- * twice, once in RW_READ and once in RW_WRITE mode to obtain 2 separate
- * pollable fds
- * - leave the core functions call the poll routine and flag POLLIN/POLLOUT
- *
- * The pipe pollable synchronous I/O works using the overlapped event associated
- * with a fake pipe. The read/write functions are only meant to be used in that
- * context.
- */
-#include <config.h>
-
-#include <errno.h>
-#include <stdio.h>
-#include <stdlib.h>
-
-#include "libusbi.h"
-
-// Uncomment to debug the polling layer
-//#define DEBUG_POLL_WINDOWS
-#if defined(DEBUG_POLL_WINDOWS)
-#define poll_dbg usbi_dbg
-#else
-// MSVC++ < 2005 cannot use a variadic argument and non MSVC
-// compilers produce warnings if parenthesis are omitted.
-#if defined(_MSC_VER) && (_MSC_VER < 1400)
-#define poll_dbg
-#else
-#define poll_dbg(...)
-#endif
-#endif
-
-#if defined(_PREFAST_)
-#pragma warning(disable:28719)
-#endif
-
-#define CHECK_INIT_POLLING do {if(!is_polling_set) init_polling();} while(0)
-
-// public fd data
-const struct winfd INVALID_WINFD = {-1, INVALID_HANDLE_VALUE, NULL, NULL, NULL, RW_NONE};
-struct winfd poll_fd[MAX_FDS];
-// internal fd data
-struct {
- CRITICAL_SECTION mutex; // lock for fds
- // Additional variables for XP CancelIoEx partial emulation
- HANDLE original_handle;
- DWORD thread_id;
-} _poll_fd[MAX_FDS];
-
-// globals
-BOOLEAN is_polling_set = FALSE;
-LONG pipe_number = 0;
-static volatile LONG compat_spinlock = 0;
-
-#if !defined(_WIN32_WCE)
-// CancelIoEx, available on Vista and later only, provides the ability to cancel
-// a single transfer (OVERLAPPED) when used. As it may not be part of any of the
-// platform headers, we hook into the Kernel32 system DLL directly to seek it.
-static BOOL (__stdcall *pCancelIoEx)(HANDLE, LPOVERLAPPED) = NULL;
-#define Use_Duplicate_Handles (pCancelIoEx == NULL)
-
-static inline void setup_cancel_io(void)
-{
- HMODULE hKernel32 = GetModuleHandleA("KERNEL32");
- if (hKernel32 != NULL) {
- pCancelIoEx = (BOOL (__stdcall *)(HANDLE,LPOVERLAPPED))
- GetProcAddress(hKernel32, "CancelIoEx");
- }
- usbi_dbg("Will use CancelIo%s for I/O cancellation",
- Use_Duplicate_Handles?"":"Ex");
-}
-
-static inline BOOL cancel_io(int _index)
-{
- if ((_index < 0) || (_index >= MAX_FDS)) {
- return FALSE;
- }
-
- if ( (poll_fd[_index].fd < 0) || (poll_fd[_index].handle == INVALID_HANDLE_VALUE)
- || (poll_fd[_index].handle == 0) || (poll_fd[_index].overlapped == NULL) ) {
- return TRUE;
- }
- if (poll_fd[_index].itransfer && poll_fd[_index].cancel_fn) {
- // Cancel outstanding transfer via the specific callback
- (*poll_fd[_index].cancel_fn)(poll_fd[_index].itransfer);
- return TRUE;
- }
- if (pCancelIoEx != NULL) {
- return (*pCancelIoEx)(poll_fd[_index].handle, poll_fd[_index].overlapped);
- }
- if (_poll_fd[_index].thread_id == GetCurrentThreadId()) {
- return CancelIo(poll_fd[_index].handle);
- }
- usbi_warn(NULL, "Unable to cancel I/O that was started from another thread");
- return FALSE;
-}
-#else
-#define Use_Duplicate_Handles FALSE
-
-static __inline void setup_cancel_io()
-{
- // No setup needed on WinCE
-}
-
-static __inline BOOL cancel_io(int _index)
-{
- if ((_index < 0) || (_index >= MAX_FDS)) {
- return FALSE;
- }
- if ( (poll_fd[_index].fd < 0) || (poll_fd[_index].handle == INVALID_HANDLE_VALUE)
- || (poll_fd[_index].handle == 0) || (poll_fd[_index].overlapped == NULL) ) {
- return TRUE;
- }
- if (poll_fd[_index].itransfer && poll_fd[_index].cancel_fn) {
- // Cancel outstanding transfer via the specific callback
- (*poll_fd[_index].cancel_fn)(poll_fd[_index].itransfer);
- }
- return TRUE;
-}
-#endif
-
-// Init
-void init_polling(void)
-{
- int i;
-
- while (InterlockedExchange((LONG *)&compat_spinlock, 1) == 1) {
- SleepEx(0, TRUE);
- }
- if (!is_polling_set) {
- setup_cancel_io();
- for (i=0; i<MAX_FDS; i++) {
- poll_fd[i] = INVALID_WINFD;
- _poll_fd[i].original_handle = INVALID_HANDLE_VALUE;
- _poll_fd[i].thread_id = 0;
- InitializeCriticalSection(&_poll_fd[i].mutex);
- }
- is_polling_set = TRUE;
- }
- InterlockedExchange((LONG *)&compat_spinlock, 0);
-}
-
-// Internal function to retrieve the table index (and lock the fd mutex)
-static int _fd_to_index_and_lock(int fd)
-{
- int i;
-
- if (fd < 0)
- return -1;
-
- for (i=0; i<MAX_FDS; i++) {
- if (poll_fd[i].fd == fd) {
- EnterCriticalSection(&_poll_fd[i].mutex);
- // fd might have changed before we got to critical
- if (poll_fd[i].fd != fd) {
- LeaveCriticalSection(&_poll_fd[i].mutex);
- continue;
- }
- return i;
- }
- }
- return -1;
-}
-
-static OVERLAPPED *create_overlapped(void)
-{
- OVERLAPPED *overlapped = (OVERLAPPED*) calloc(1, sizeof(OVERLAPPED));
- if (overlapped == NULL) {
- return NULL;
- }
- overlapped->hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
- if(overlapped->hEvent == NULL) {
- free (overlapped);
- return NULL;
- }
- return overlapped;
-}
-
-static void free_overlapped(OVERLAPPED *overlapped)
-{
- if (overlapped == NULL)
- return;
-
- if ( (overlapped->hEvent != 0)
- && (overlapped->hEvent != INVALID_HANDLE_VALUE) ) {
- CloseHandle(overlapped->hEvent);
- }
- free(overlapped);
-}
-
-void exit_polling(void)
-{
- int i;
-
- while (InterlockedExchange((LONG *)&compat_spinlock, 1) == 1) {
- SleepEx(0, TRUE);
- }
- if (is_polling_set) {
- is_polling_set = FALSE;
-
- for (i=0; i<MAX_FDS; i++) {
- // Cancel any async I/O (handle can be invalid)
- cancel_io(i);
- // If anything was pending on that I/O, it should be
- // terminating, and we should be able to access the fd
- // mutex lock before too long
- EnterCriticalSection(&_poll_fd[i].mutex);
- free_overlapped(poll_fd[i].overlapped);
- if (Use_Duplicate_Handles) {
- // Close duplicate handle
- if (_poll_fd[i].original_handle != INVALID_HANDLE_VALUE) {
- CloseHandle(poll_fd[i].handle);
- }
- }
- poll_fd[i] = INVALID_WINFD;
- LeaveCriticalSection(&_poll_fd[i].mutex);
- DeleteCriticalSection(&_poll_fd[i].mutex);
- }
- }
- InterlockedExchange((LONG *)&compat_spinlock, 0);
-}
-
-/*
- * Create a fake pipe.
- * As libusb only uses pipes for signaling, all we need from a pipe is an
- * event. To that extent, we create a single wfd and overlapped as a means
- * to access that event.
- */
-int usbi_pipe(int filedes[2])
-{
- int i;
- OVERLAPPED* overlapped;
-
- CHECK_INIT_POLLING;
-
- overlapped = create_overlapped();
-
- if (overlapped == NULL) {
- return -1;
- }
- // The overlapped must have status pending for signaling to work in poll
- overlapped->Internal = STATUS_PENDING;
- overlapped->InternalHigh = 0;
-
- for (i=0; i<MAX_FDS; i++) {
- if (poll_fd[i].fd < 0) {
- EnterCriticalSection(&_poll_fd[i].mutex);
- // fd might have been allocated before we got to critical
- if (poll_fd[i].fd >= 0) {
- LeaveCriticalSection(&_poll_fd[i].mutex);
- continue;
- }
-
- // Use index as the unique fd number
- poll_fd[i].fd = i;
- // Read end of the "pipe"
- filedes[0] = poll_fd[i].fd;
- // We can use the same handle for both ends
- filedes[1] = filedes[0];
-
- poll_fd[i].handle = DUMMY_HANDLE;
- poll_fd[i].overlapped = overlapped;
- // There's no polling on the write end, so we just use READ for our needs
- poll_fd[i].rw = RW_READ;
- _poll_fd[i].original_handle = INVALID_HANDLE_VALUE;
- LeaveCriticalSection(&_poll_fd[i].mutex);
- return 0;
- }
- }
- free_overlapped(overlapped);
- return -1;
-}
-
-/*
- * Create both an fd and an OVERLAPPED from an open Windows handle, so that
- * it can be used with our polling function
- * The handle MUST support overlapped transfers (usually requires CreateFile
- * with FILE_FLAG_OVERLAPPED)
- * Return a pollable file descriptor struct, or INVALID_WINFD on error
- *
- * Note that the fd returned by this function is a per-transfer fd, rather
- * than a per-session fd and cannot be used for anything else but our
- * custom functions (the fd itself points to the NUL: device)
- * if you plan to do R/W on the same handle, you MUST create 2 fds: one for
- * read and one for write. Using a single R/W fd is unsupported and will
- * produce unexpected results
- */
-struct winfd usbi_create_fd(HANDLE handle, int access_mode, struct usbi_transfer *itransfer, cancel_transfer *cancel_fn)
-{
- int i;
- struct winfd wfd = INVALID_WINFD;
- OVERLAPPED* overlapped = NULL;
-
- CHECK_INIT_POLLING;
-
- if ((handle == 0) || (handle == INVALID_HANDLE_VALUE)) {
- return INVALID_WINFD;
- }
-
- wfd.itransfer = itransfer;
- wfd.cancel_fn = cancel_fn;
-
- if ((access_mode != RW_READ) && (access_mode != RW_WRITE)) {
- usbi_warn(NULL, "only one of RW_READ or RW_WRITE are supported. "
- "If you want to poll for R/W simultaneously, create multiple fds from the same handle.");
- return INVALID_WINFD;
- }
- if (access_mode == RW_READ) {
- wfd.rw = RW_READ;
- } else {
- wfd.rw = RW_WRITE;
- }
-
- overlapped = create_overlapped();
- if(overlapped == NULL) {
- return INVALID_WINFD;
- }
-
- for (i=0; i<MAX_FDS; i++) {
- if (poll_fd[i].fd < 0) {
- EnterCriticalSection(&_poll_fd[i].mutex);
- // fd might have been removed before we got to critical
- if (poll_fd[i].fd >= 0) {
- LeaveCriticalSection(&_poll_fd[i].mutex);
- continue;
- }
- // Use index as the unique fd number
- wfd.fd = i;
- // Attempt to emulate some of the CancelIoEx behaviour on platforms
- // that don't have it
- if (Use_Duplicate_Handles) {
- _poll_fd[i].thread_id = GetCurrentThreadId();
- if (!DuplicateHandle(GetCurrentProcess(), handle, GetCurrentProcess(),
- &wfd.handle, 0, TRUE, DUPLICATE_SAME_ACCESS)) {
- usbi_dbg("could not duplicate handle for CancelIo - using original one");
- wfd.handle = handle;
- // Make sure we won't close the original handle on fd deletion then
- _poll_fd[i].original_handle = INVALID_HANDLE_VALUE;
- } else {
- _poll_fd[i].original_handle = handle;
- }
- } else {
- wfd.handle = handle;
- }
- wfd.overlapped = overlapped;
- memcpy(&poll_fd[i], &wfd, sizeof(struct winfd));
- LeaveCriticalSection(&_poll_fd[i].mutex);
- return wfd;
- }
- }
- free_overlapped(overlapped);
- return INVALID_WINFD;
-}
-
-static void _free_index(int _index)
-{
- // Cancel any async IO (Don't care about the validity of our handles for this)
- cancel_io(_index);
- // close the duplicate handle (if we have an actual duplicate)
- if (Use_Duplicate_Handles) {
- if (_poll_fd[_index].original_handle != INVALID_HANDLE_VALUE) {
- CloseHandle(poll_fd[_index].handle);
- }
- _poll_fd[_index].original_handle = INVALID_HANDLE_VALUE;
- _poll_fd[_index].thread_id = 0;
- }
- free_overlapped(poll_fd[_index].overlapped);
- poll_fd[_index] = INVALID_WINFD;
-}
-
-/*
- * Release a pollable file descriptor.
- *
- * Note that the associated Windows handle is not closed by this call
- */
-void usbi_free_fd(struct winfd *wfd)
-{
- int _index;
-
- CHECK_INIT_POLLING;
-
- _index = _fd_to_index_and_lock(wfd->fd);
- if (_index < 0) {
- return;
- }
- _free_index(_index);
- *wfd = INVALID_WINFD;
- LeaveCriticalSection(&_poll_fd[_index].mutex);
-}
-
-/*
- * The functions below perform various conversions between fd, handle and OVERLAPPED
- */
-struct winfd fd_to_winfd(int fd)
-{
- int i;
- struct winfd wfd;
-
- CHECK_INIT_POLLING;
-
- if (fd < 0)
- return INVALID_WINFD;
-
- for (i=0; i<MAX_FDS; i++) {
- if (poll_fd[i].fd == fd) {
- EnterCriticalSection(&_poll_fd[i].mutex);
- // fd might have been deleted before we got to critical
- if (poll_fd[i].fd != fd) {
- LeaveCriticalSection(&_poll_fd[i].mutex);
- continue;
- }
- memcpy(&wfd, &poll_fd[i], sizeof(struct winfd));
- LeaveCriticalSection(&_poll_fd[i].mutex);
- return wfd;
- }
- }
- return INVALID_WINFD;
-}
-
-struct winfd handle_to_winfd(HANDLE handle)
-{
- int i;
- struct winfd wfd;
-
- CHECK_INIT_POLLING;
-
- if ((handle == 0) || (handle == INVALID_HANDLE_VALUE))
- return INVALID_WINFD;
-
- for (i=0; i<MAX_FDS; i++) {
- if (poll_fd[i].handle == handle) {
- EnterCriticalSection(&_poll_fd[i].mutex);
- // fd might have been deleted before we got to critical
- if (poll_fd[i].handle != handle) {
- LeaveCriticalSection(&_poll_fd[i].mutex);
- continue;
- }
- memcpy(&wfd, &poll_fd[i], sizeof(struct winfd));
- LeaveCriticalSection(&_poll_fd[i].mutex);
- return wfd;
- }
- }
- return INVALID_WINFD;
-}
-
-struct winfd overlapped_to_winfd(OVERLAPPED* overlapped)
-{
- int i;
- struct winfd wfd;
-
- CHECK_INIT_POLLING;
-
- if (overlapped == NULL)
- return INVALID_WINFD;
-
- for (i=0; i<MAX_FDS; i++) {
- if (poll_fd[i].overlapped == overlapped) {
- EnterCriticalSection(&_poll_fd[i].mutex);
- // fd might have been deleted before we got to critical
- if (poll_fd[i].overlapped != overlapped) {
- LeaveCriticalSection(&_poll_fd[i].mutex);
- continue;
- }
- memcpy(&wfd, &poll_fd[i], sizeof(struct winfd));
- LeaveCriticalSection(&_poll_fd[i].mutex);
- return wfd;
- }
- }
- return INVALID_WINFD;
-}
-
-/*
- * POSIX poll equivalent, using Windows OVERLAPPED
- * Currently, this function only accepts one of POLLIN or POLLOUT per fd
- * (but you can create multiple fds from the same handle for read and write)
- */
-int usbi_poll(struct pollfd *fds, unsigned int nfds, int timeout)
-{
- unsigned i;
- int _index, object_index, triggered;
- HANDLE *handles_to_wait_on;
- int *handle_to_index;
- DWORD nb_handles_to_wait_on = 0;
- DWORD ret;
-
- CHECK_INIT_POLLING;
-
- triggered = 0;
- handles_to_wait_on = (HANDLE*) calloc(nfds+1, sizeof(HANDLE)); // +1 for fd_update
- handle_to_index = (int*) calloc(nfds, sizeof(int));
- if ((handles_to_wait_on == NULL) || (handle_to_index == NULL)) {
- errno = ENOMEM;
- triggered = -1;
- goto poll_exit;
- }
-
- for (i = 0; i < nfds; ++i) {
- fds[i].revents = 0;
-
- // Only one of POLLIN or POLLOUT can be selected with this version of poll (not both)
- if ((fds[i].events & ~POLLIN) && (!(fds[i].events & POLLOUT))) {
- fds[i].revents |= POLLERR;
- errno = EACCES;
- usbi_warn(NULL, "unsupported set of events");
- triggered = -1;
- goto poll_exit;
- }
-
- _index = _fd_to_index_and_lock(fds[i].fd);
- poll_dbg("fd[%d]=%d: (overlapped=%p) got events %04X", i, poll_fd[_index].fd, poll_fd[_index].overlapped, fds[i].events);
-
- if ( (_index < 0) || (poll_fd[_index].handle == INVALID_HANDLE_VALUE)
- || (poll_fd[_index].handle == 0) || (poll_fd[_index].overlapped == NULL)) {
- fds[i].revents |= POLLNVAL | POLLERR;
- errno = EBADF;
- if (_index >= 0) {
- LeaveCriticalSection(&_poll_fd[_index].mutex);
- }
- usbi_warn(NULL, "invalid fd");
- triggered = -1;
- goto poll_exit;
- }
-
- // IN or OUT must match our fd direction
- if ((fds[i].events & POLLIN) && (poll_fd[_index].rw != RW_READ)) {
- fds[i].revents |= POLLNVAL | POLLERR;
- errno = EBADF;
- usbi_warn(NULL, "attempted POLLIN on fd without READ access");
- LeaveCriticalSection(&_poll_fd[_index].mutex);
- triggered = -1;
- goto poll_exit;
- }
-
- if ((fds[i].events & POLLOUT) && (poll_fd[_index].rw != RW_WRITE)) {
- fds[i].revents |= POLLNVAL | POLLERR;
- errno = EBADF;
- usbi_warn(NULL, "attempted POLLOUT on fd without WRITE access");
- LeaveCriticalSection(&_poll_fd[_index].mutex);
- triggered = -1;
- goto poll_exit;
- }
-
- // The following macro only works if overlapped I/O was reported pending
- if ( (HasOverlappedIoCompleted(poll_fd[_index].overlapped))
- || (HasOverlappedIoCompletedSync(poll_fd[_index].overlapped)) ) {
- poll_dbg(" completed");
- // checks above should ensure this works:
- fds[i].revents = fds[i].events;
- triggered++;
- } else {
- handles_to_wait_on[nb_handles_to_wait_on] = poll_fd[_index].overlapped->hEvent;
- handle_to_index[nb_handles_to_wait_on] = i;
- nb_handles_to_wait_on++;
- }
- LeaveCriticalSection(&_poll_fd[_index].mutex);
- }
-
- // If nothing was triggered, wait on all fds that require it
- if ((timeout != 0) && (triggered == 0) && (nb_handles_to_wait_on != 0)) {
- if (timeout < 0) {
- poll_dbg("starting infinite wait for %u handles...", (unsigned int)nb_handles_to_wait_on);
- } else {
- poll_dbg("starting %d ms wait for %u handles...", timeout, (unsigned int)nb_handles_to_wait_on);
- }
- ret = WaitForMultipleObjects(nb_handles_to_wait_on, handles_to_wait_on,
- FALSE, (timeout<0)?INFINITE:(DWORD)timeout);
- object_index = ret-WAIT_OBJECT_0;
- if ((object_index >= 0) && ((DWORD)object_index < nb_handles_to_wait_on)) {
- poll_dbg(" completed after wait");
- i = handle_to_index[object_index];
- _index = _fd_to_index_and_lock(fds[i].fd);
- fds[i].revents = fds[i].events;
- triggered++;
- if (_index >= 0) {
- LeaveCriticalSection(&_poll_fd[_index].mutex);
- }
- } else if (ret == WAIT_TIMEOUT) {
- poll_dbg(" timed out");
- triggered = 0; // 0 = timeout
- } else {
- errno = EIO;
- triggered = -1; // error
- }
- }
-
-poll_exit:
- if (handles_to_wait_on != NULL) {
- free(handles_to_wait_on);
- }
- if (handle_to_index != NULL) {
- free(handle_to_index);
- }
- return triggered;
-}
-
-/*
- * close a fake pipe fd
- */
-int usbi_close(int fd)
-{
- int _index;
- int r = -1;
-
- CHECK_INIT_POLLING;
-
- _index = _fd_to_index_and_lock(fd);
-
- if (_index < 0) {
- errno = EBADF;
- } else {
- free_overlapped(poll_fd[_index].overlapped);
- poll_fd[_index] = INVALID_WINFD;
- LeaveCriticalSection(&_poll_fd[_index].mutex);
- }
- return r;
-}
-
-/*
- * synchronous write for fake "pipe" signaling
- */
-ssize_t usbi_write(int fd, const void *buf, size_t count)
-{
- int _index;
- UNUSED(buf);
-
- CHECK_INIT_POLLING;
-
- if (count != sizeof(unsigned char)) {
- usbi_err(NULL, "this function should only used for signaling");
- return -1;
- }
-
- _index = _fd_to_index_and_lock(fd);
-
- if ( (_index < 0) || (poll_fd[_index].overlapped == NULL) ) {
- errno = EBADF;
- if (_index >= 0) {
- LeaveCriticalSection(&_poll_fd[_index].mutex);
- }
- return -1;
- }
-
- poll_dbg("set pipe event (fd = %d, thread = %08X)", _index, (unsigned int)GetCurrentThreadId());
- SetEvent(poll_fd[_index].overlapped->hEvent);
- poll_fd[_index].overlapped->Internal = STATUS_WAIT_0;
- // If two threads write on the pipe at the same time, we need to
- // process two separate reads => use the overlapped as a counter
- poll_fd[_index].overlapped->InternalHigh++;
-
- LeaveCriticalSection(&_poll_fd[_index].mutex);
- return sizeof(unsigned char);
-}
-
-/*
- * synchronous read for fake "pipe" signaling
- */
-ssize_t usbi_read(int fd, void *buf, size_t count)
-{
- int _index;
- ssize_t r = -1;
- UNUSED(buf);
-
- CHECK_INIT_POLLING;
-
- if (count != sizeof(unsigned char)) {
- usbi_err(NULL, "this function should only used for signaling");
- return -1;
- }
-
- _index = _fd_to_index_and_lock(fd);
-
- if (_index < 0) {
- errno = EBADF;
- return -1;
- }
-
- if (WaitForSingleObject(poll_fd[_index].overlapped->hEvent, INFINITE) != WAIT_OBJECT_0) {
- usbi_warn(NULL, "waiting for event failed: %u", (unsigned int)GetLastError());
- errno = EIO;
- goto out;
- }
-
- poll_dbg("clr pipe event (fd = %d, thread = %08X)", _index, (unsigned int)GetCurrentThreadId());
- poll_fd[_index].overlapped->InternalHigh--;
- // Don't reset unless we don't have any more events to process
- if (poll_fd[_index].overlapped->InternalHigh <= 0) {
- ResetEvent(poll_fd[_index].overlapped->hEvent);
- poll_fd[_index].overlapped->Internal = STATUS_PENDING;
- }
-
- r = sizeof(unsigned char);
-
-out:
- LeaveCriticalSection(&_poll_fd[_index].mutex);
- return r;
-}