diff options
Diffstat (limited to 'libusb/os/windows_nt_common.c')
| -rw-r--r-- | libusb/os/windows_nt_common.c | 616 |
1 files changed, 616 insertions, 0 deletions
diff --git a/libusb/os/windows_nt_common.c b/libusb/os/windows_nt_common.c new file mode 100644 index 0000000..d99e3b8 --- /dev/null +++ b/libusb/os/windows_nt_common.c @@ -0,0 +1,616 @@ +/* + * windows backend for libusb 1.0 + * Copyright © 2009-2012 Pete Batard <pete@akeo.ie> + * With contributions from Michael Plante, Orin Eman et al. + * Parts of this code adapted from libusb-win32-v1 by Stephan Meyer + * HID Reports IOCTLs inspired from HIDAPI by Alan Ott, Signal 11 Software + * Hash table functions adapted from glibc, by Ulrich Drepper et al. + * Major code testing contribution by Xiaofan Chen + * + * 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 + */ + +#include <config.h> +#include <stdio.h> +#include <inttypes.h> +#include <process.h> + + +#include "libusbi.h" +#include "windows_common.h" +#include "windows_nt_common.h" + +// Global variables +const uint64_t epoch_time = UINT64_C(116444736000000000); // 1970.01.01 00:00:000 in MS Filetime + +// Global variables for clock_gettime mechanism +uint64_t hires_ticks_to_ps; +uint64_t hires_frequency; + +#define WM_TIMER_REQUEST (WM_USER + 1) +#define WM_TIMER_EXIT (WM_USER + 2) + +// used for monotonic clock_gettime() +struct timer_request { + struct timespec *tp; + HANDLE event; +}; + +// Timer thread +HANDLE timer_thread = NULL; +DWORD timer_thread_id = 0; + +/* User32 dependencies */ +DLL_DECLARE_PREFIXED(WINAPI, BOOL, p, GetMessageA, (LPMSG, HWND, UINT, UINT)); +DLL_DECLARE_PREFIXED(WINAPI, BOOL, p, PeekMessageA, (LPMSG, HWND, UINT, UINT, UINT)); +DLL_DECLARE_PREFIXED(WINAPI, BOOL, p, PostThreadMessageA, (DWORD, UINT, WPARAM, LPARAM)); + +static unsigned __stdcall windows_clock_gettime_threaded(void* param); + +/* +* Converts a windows error to human readable string +* uses retval as errorcode, or, if 0, use GetLastError() +*/ +#if defined(ENABLE_LOGGING) +char *windows_error_str(uint32_t retval) +{ + static char err_string[ERR_BUFFER_SIZE]; + + DWORD size; + ssize_t i; + uint32_t error_code, format_error; + + error_code = retval ? retval : GetLastError(); + + safe_sprintf(err_string, ERR_BUFFER_SIZE, "[%u] ", error_code); + + // Translate codes returned by SetupAPI. The ones we are dealing with are either + // in 0x0000xxxx or 0xE000xxxx and can be distinguished from standard error codes. + // See http://msdn.microsoft.com/en-us/library/windows/hardware/ff545011.aspx + switch (error_code & 0xE0000000) { + case 0: + error_code = HRESULT_FROM_WIN32(error_code); // Still leaves ERROR_SUCCESS unmodified + break; + case 0xE0000000: + error_code = 0x80000000 | (FACILITY_SETUPAPI << 16) | (error_code & 0x0000FFFF); + break; + default: + break; + } + + size = FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error_code, + MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), &err_string[safe_strlen(err_string)], + ERR_BUFFER_SIZE - (DWORD)safe_strlen(err_string), NULL); + if (size == 0) { + format_error = GetLastError(); + if (format_error) + safe_sprintf(err_string, ERR_BUFFER_SIZE, + "Windows error code %u (FormatMessage error code %u)", error_code, format_error); + else + safe_sprintf(err_string, ERR_BUFFER_SIZE, "Unknown error code %u", error_code); + } + else { + // Remove CR/LF terminators + for (i = safe_strlen(err_string) - 1; (i >= 0) && ((err_string[i] == 0x0A) || (err_string[i] == 0x0D)); i--) { + err_string[i] = 0; + } + } + return err_string; +} +#endif + +/* Hash table functions - modified From glibc 2.3.2: + [Aho,Sethi,Ullman] Compilers: Principles, Techniques and Tools, 1986 + [Knuth] The Art of Computer Programming, part 3 (6.4) */ +typedef struct htab_entry { + unsigned long used; + char* str; +} htab_entry; +htab_entry* htab_table = NULL; +usbi_mutex_t htab_write_mutex = NULL; +unsigned long htab_size, htab_filled; + +/* For the used double hash method the table size has to be a prime. To + correct the user given table size we need a prime test. This trivial + algorithm is adequate because the code is called only during init and + the number is likely to be small */ +static int isprime(unsigned long number) +{ + // no even number will be passed + unsigned int divider = 3; + + while((divider * divider < number) && (number % divider != 0)) + divider += 2; + + return (number % divider != 0); +} + +/* Before using the hash table we must allocate memory for it. + We allocate one element more as the found prime number says. + This is done for more effective indexing as explained in the + comment for the hash function. */ +int htab_create(struct libusb_context *ctx, unsigned long nel) +{ + if (htab_table != NULL) { + usbi_err(ctx, "hash table already allocated"); + } + + // Create a mutex + usbi_mutex_init(&htab_write_mutex, NULL); + + // Change nel to the first prime number not smaller as nel. + nel |= 1; + while(!isprime(nel)) + nel += 2; + + htab_size = nel; + usbi_dbg("using %lu entries hash table", nel); + htab_filled = 0; + + // allocate memory and zero out. + htab_table = (htab_entry*) calloc(htab_size + 1, sizeof(htab_entry)); + if (htab_table == NULL) { + usbi_err(ctx, "could not allocate space for hash table"); + return 0; + } + + return 1; +} + +/* After using the hash table it has to be destroyed. */ +void htab_destroy(void) +{ + size_t i; + if (htab_table == NULL) { + return; + } + + for (i=0; i<htab_size; i++) { + if (htab_table[i].used) { + safe_free(htab_table[i].str); + } + } + usbi_mutex_destroy(&htab_write_mutex); + safe_free(htab_table); +} + +/* This is the search function. It uses double hashing with open addressing. + We use an trick to speed up the lookup. The table is created with one + more element available. This enables us to use the index zero special. + This index will never be used because we store the first hash index in + the field used where zero means not used. Every other value means used. + The used field can be used as a first fast comparison for equality of + the stored and the parameter value. This helps to prevent unnecessary + expensive calls of strcmp. */ +unsigned long htab_hash(char* str) +{ + unsigned long hval, hval2; + unsigned long idx; + unsigned long r = 5381; + int c; + char* sz = str; + + if (str == NULL) + return 0; + + // Compute main hash value (algorithm suggested by Nokia) + while ((c = *sz++) != 0) + r = ((r << 5) + r) + c; + if (r == 0) + ++r; + + // compute table hash: simply take the modulus + hval = r % htab_size; + if (hval == 0) + ++hval; + + // Try the first index + idx = hval; + + if (htab_table[idx].used) { + if ( (htab_table[idx].used == hval) + && (safe_strcmp(str, htab_table[idx].str) == 0) ) { + // existing hash + return idx; + } + usbi_dbg("hash collision ('%s' vs '%s')", str, htab_table[idx].str); + + // Second hash function, as suggested in [Knuth] + hval2 = 1 + hval % (htab_size - 2); + + do { + // Because size is prime this guarantees to step through all available indexes + if (idx <= hval2) { + idx = htab_size + idx - hval2; + } else { + idx -= hval2; + } + + // If we visited all entries leave the loop unsuccessfully + if (idx == hval) { + break; + } + + // If entry is found use it. + if ( (htab_table[idx].used == hval) + && (safe_strcmp(str, htab_table[idx].str) == 0) ) { + return idx; + } + } + while (htab_table[idx].used); + } + + // Not found => New entry + + // If the table is full return an error + if (htab_filled >= htab_size) { + usbi_err(NULL, "hash table is full (%d entries)", htab_size); + return 0; + } + + // Concurrent threads might be storing the same entry at the same time + // (eg. "simultaneous" enums from different threads) => use a mutex + usbi_mutex_lock(&htab_write_mutex); + // Just free any previously allocated string (which should be the same as + // new one). The possibility of concurrent threads storing a collision + // string (same hash, different string) at the same time is extremely low + safe_free(htab_table[idx].str); + htab_table[idx].used = hval; + htab_table[idx].str = (char*) malloc(safe_strlen(str)+1); + if (htab_table[idx].str == NULL) { + usbi_err(NULL, "could not duplicate string for hash table"); + usbi_mutex_unlock(&htab_write_mutex); + return 0; + } + memcpy(htab_table[idx].str, str, safe_strlen(str)+1); + ++htab_filled; + usbi_mutex_unlock(&htab_write_mutex); + + return idx; +} + +static int windows_init_dlls(void) +{ + DLL_LOAD_PREFIXED(User32.dll, p, GetMessageA, TRUE); + DLL_LOAD_PREFIXED(User32.dll, p, PeekMessageA, TRUE); + DLL_LOAD_PREFIXED(User32.dll, p, PostThreadMessageA, TRUE); + return LIBUSB_SUCCESS; +} + +bool windows_init_clock(struct libusb_context *ctx) +{ + DWORD_PTR affinity, dummy; + HANDLE event = NULL; + LARGE_INTEGER li_frequency; + int i; + + if (QueryPerformanceFrequency(&li_frequency)) { + // Load DLL imports + if (windows_init_dlls() != LIBUSB_SUCCESS) { + usbi_err(ctx, "could not resolve DLL functions"); + return false; + } + + // The hires frequency can go as high as 4 GHz, so we'll use a conversion + // to picoseconds to compute the tv_nsecs part in clock_gettime + hires_frequency = li_frequency.QuadPart; + hires_ticks_to_ps = UINT64_C(1000000000000) / hires_frequency; + usbi_dbg("hires timer available (Frequency: %"PRIu64" Hz)", hires_frequency); + + // Because QueryPerformanceCounter might report different values when + // running on different cores, we create a separate thread for the timer + // calls, which we glue to the first available core always to prevent timing discrepancies. + if (!GetProcessAffinityMask(GetCurrentProcess(), &affinity, &dummy) || (affinity == 0)) { + usbi_err(ctx, "could not get process affinity: %s", windows_error_str(0)); + return false; + } + // The process affinity mask is a bitmask where each set bit represents a core on + // which this process is allowed to run, so we find the first set bit + for (i = 0; !(affinity & (DWORD_PTR)(1 << i)); i++); + affinity = (DWORD_PTR)(1 << i); + + usbi_dbg("timer thread will run on core #%d", i); + + event = CreateEvent(NULL, FALSE, FALSE, NULL); + if (event == NULL) { + usbi_err(ctx, "could not create event: %s", windows_error_str(0)); + return false; + } + timer_thread = (HANDLE)_beginthreadex(NULL, 0, windows_clock_gettime_threaded, (void *)event, + 0, (unsigned int *)&timer_thread_id); + if (timer_thread == NULL) { + usbi_err(ctx, "unable to create timer thread - aborting"); + CloseHandle(event); + return false; + } + if (!SetThreadAffinityMask(timer_thread, affinity)) { + usbi_warn(ctx, "unable to set timer thread affinity, timer discrepancies may arise"); + } + + // Wait for timer thread to init before continuing. + if (WaitForSingleObject(event, INFINITE) != WAIT_OBJECT_0) { + usbi_err(ctx, "failed to wait for timer thread to become ready - aborting"); + CloseHandle(event); + return false; + } + + CloseHandle(event); + } else { + usbi_dbg("no hires timer available on this platform"); + hires_frequency = 0; + hires_ticks_to_ps = UINT64_C(0); + } + + return true; +} + +void windows_destroy_clock(void) +{ + if (timer_thread) { + // actually the signal to quit the thread. + if (!pPostThreadMessageA(timer_thread_id, WM_TIMER_EXIT, 0, 0) || + (WaitForSingleObject(timer_thread, INFINITE) != WAIT_OBJECT_0)) { + usbi_dbg("could not wait for timer thread to quit"); + TerminateThread(timer_thread, 1); + // shouldn't happen, but we're destroying + // all objects it might have held anyway. + } + CloseHandle(timer_thread); + timer_thread = NULL; + timer_thread_id = 0; + } +} + +/* +* Monotonic and real time functions +*/ +static unsigned __stdcall windows_clock_gettime_threaded(void* param) +{ + struct timer_request *request; + LARGE_INTEGER hires_counter; + MSG msg; + + // The following call will create this thread's message queue + // See https://msdn.microsoft.com/en-us/library/windows/desktop/ms644946.aspx + pPeekMessageA(&msg, NULL, WM_USER, WM_USER, PM_NOREMOVE); + + // Signal windows_init() that we're ready to service requests + if (!SetEvent((HANDLE)param)) { + usbi_dbg("SetEvent failed for timer init event: %s", windows_error_str(0)); + } + param = NULL; + + // Main loop - wait for requests + while (1) { + + if (pGetMessageA(&msg, NULL, WM_TIMER_REQUEST, WM_TIMER_EXIT) == -1) { + usbi_err(NULL, "GetMessage failed for timer thread: %s", windows_error_str(0)); + return 1; + } + + switch (msg.message) { + case WM_TIMER_REQUEST: + // Requests to this thread are for hires always + // Microsoft says that this function always succeeds on XP and later + // See https://msdn.microsoft.com/en-us/library/windows/desktop/ms644904.aspx + request = (struct timer_request *)msg.lParam; + QueryPerformanceCounter(&hires_counter); + request->tp->tv_sec = (long)(hires_counter.QuadPart / hires_frequency); + request->tp->tv_nsec = (long)(((hires_counter.QuadPart % hires_frequency) / 1000) * hires_ticks_to_ps); + if (!SetEvent(request->event)) { + usbi_err(NULL, "SetEvent failed for timer request: %s", windows_error_str(0)); + } + break; + + case WM_TIMER_EXIT: + usbi_dbg("timer thread quitting"); + return 0; + } + + } +} + +int windows_clock_gettime(int clk_id, struct timespec *tp) +{ + struct timer_request request; + FILETIME filetime; + ULARGE_INTEGER rtime; + DWORD r; + switch (clk_id) { + case USBI_CLOCK_MONOTONIC: + if (timer_thread) { + request.tp = tp; + request.event = CreateEvent(NULL, FALSE, FALSE, NULL); + if (request.event == NULL) { + return LIBUSB_ERROR_NO_MEM; + } + + if (!pPostThreadMessageA(timer_thread_id, WM_TIMER_REQUEST, 0, (LPARAM)&request)) { + usbi_err(NULL, "PostThreadMessage failed for timer thread: %s", windows_error_str(0)); + CloseHandle(request.event); + return LIBUSB_ERROR_OTHER; + } + + do { + r = WaitForSingleObject(request.event, TIMER_REQUEST_RETRY_MS); + if (r == WAIT_TIMEOUT) { + usbi_dbg("could not obtain a timer value within reasonable timeframe - too much load?"); + } + else if (r == WAIT_FAILED) { + usbi_err(NULL, "WaitForSingleObject failed: %s", windows_error_str(0)); + } + } while (r == WAIT_TIMEOUT); + CloseHandle(request.event); + + if (r == WAIT_OBJECT_0) { + return LIBUSB_SUCCESS; + } else { + return LIBUSB_ERROR_OTHER; + } + } + // Fall through and return real-time if monotonic was not detected @ timer init + case USBI_CLOCK_REALTIME: + // We follow http://msdn.microsoft.com/en-us/library/ms724928%28VS.85%29.aspx + // with a predef epoch_time to have an epoch that starts at 1970.01.01 00:00 + // Note however that our resolution is bounded by the Windows system time + // functions and is at best of the order of 1 ms (or, usually, worse) + GetSystemTimeAsFileTime(&filetime); + rtime.LowPart = filetime.dwLowDateTime; + rtime.HighPart = filetime.dwHighDateTime; + rtime.QuadPart -= epoch_time; + tp->tv_sec = (long)(rtime.QuadPart / 10000000); + tp->tv_nsec = (long)((rtime.QuadPart % 10000000) * 100); + return LIBUSB_SUCCESS; + default: + return LIBUSB_ERROR_INVALID_PARAM; + } +} + +static void windows_transfer_callback(struct usbi_transfer *itransfer, uint32_t io_result, uint32_t io_size) +{ + int status, istatus; + + usbi_dbg("handling I/O completion with errcode %u, size %u", io_result, io_size); + + switch (io_result) { + case NO_ERROR: + status = windows_copy_transfer_data(itransfer, io_size); + break; + case ERROR_GEN_FAILURE: + usbi_dbg("detected endpoint stall"); + status = LIBUSB_TRANSFER_STALL; + break; + case ERROR_SEM_TIMEOUT: + usbi_dbg("detected semaphore timeout"); + status = LIBUSB_TRANSFER_TIMED_OUT; + break; + case ERROR_OPERATION_ABORTED: + istatus = windows_copy_transfer_data(itransfer, io_size); + if (istatus != LIBUSB_TRANSFER_COMPLETED) { + usbi_dbg("Failed to copy partial data in aborted operation: %d", istatus); + } + if (itransfer->flags & USBI_TRANSFER_TIMED_OUT) { + usbi_dbg("detected timeout"); + status = LIBUSB_TRANSFER_TIMED_OUT; + } + else { + usbi_dbg("detected operation aborted"); + status = LIBUSB_TRANSFER_CANCELLED; + } + break; + default: + usbi_err(ITRANSFER_CTX(itransfer), "detected I/O error %u: %s", io_result, windows_error_str(io_result)); + status = LIBUSB_TRANSFER_ERROR; + break; + } + windows_clear_transfer_priv(itransfer); // Cancel polling + usbi_handle_transfer_completion(itransfer, (enum libusb_transfer_status)status); +} + +void windows_handle_callback(struct usbi_transfer *itransfer, uint32_t io_result, uint32_t io_size) +{ + struct libusb_transfer *transfer = USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer); + + switch (transfer->type) { + case LIBUSB_TRANSFER_TYPE_CONTROL: + case LIBUSB_TRANSFER_TYPE_BULK: + case LIBUSB_TRANSFER_TYPE_INTERRUPT: + case LIBUSB_TRANSFER_TYPE_ISOCHRONOUS: + windows_transfer_callback(itransfer, io_result, io_size); + break; + case LIBUSB_TRANSFER_TYPE_BULK_STREAM: + usbi_warn(ITRANSFER_CTX(itransfer), "bulk stream transfers are not yet supported on this platform"); + break; + default: + usbi_err(ITRANSFER_CTX(itransfer), "unknown endpoint type %d", transfer->type); + } +} + +int windows_handle_events(struct libusb_context *ctx, struct pollfd *fds, POLL_NFDS_TYPE nfds, int num_ready) +{ + POLL_NFDS_TYPE i = 0; + bool found = false; + struct usbi_transfer *transfer; + struct winfd *pollable_fd = NULL; + DWORD io_size, io_result; + + usbi_mutex_lock(&ctx->open_devs_lock); + for (i = 0; i < nfds && num_ready > 0; i++) { + + usbi_dbg("checking fd %d with revents = %04x", fds[i].fd, fds[i].revents); + + if (!fds[i].revents) { + continue; + } + + num_ready--; + + // Because a Windows OVERLAPPED is used for poll emulation, + // a pollable fd is created and stored with each transfer + usbi_mutex_lock(&ctx->flying_transfers_lock); + found = false; + list_for_each_entry(transfer, &ctx->flying_transfers, list, struct usbi_transfer) { + pollable_fd = windows_get_fd(transfer); + if (pollable_fd->fd == fds[i].fd) { + found = true; + break; + } + } + usbi_mutex_unlock(&ctx->flying_transfers_lock); + + if (found) { + windows_get_overlapped_result(transfer, pollable_fd, &io_result, &io_size); + + usbi_remove_pollfd(ctx, pollable_fd->fd); + // let handle_callback free the event using the transfer wfd + // If you don't use the transfer wfd, you run a risk of trying to free a + // newly allocated wfd that took the place of the one from the transfer. + windows_handle_callback(transfer, io_result, io_size); + } else { + usbi_mutex_unlock(&ctx->open_devs_lock); + usbi_err(ctx, "could not find a matching transfer for fd %d", fds[i]); + return LIBUSB_ERROR_NOT_FOUND; + } + } + + usbi_mutex_unlock(&ctx->open_devs_lock); + return LIBUSB_SUCCESS; +} + +int windows_common_init(struct libusb_context *ctx) +{ + static const unsigned long HTAB_SIZE = 1021; + + if (!windows_init_clock(ctx)){ + goto error_roll_back; + } + + if (!htab_create(ctx, HTAB_SIZE)) { + goto error_roll_back; + } + + return LIBUSB_SUCCESS; + +error_roll_back: + windows_common_exit(); + + return LIBUSB_ERROR_NO_MEM; +} + +void windows_common_exit(void) +{ + htab_destroy(); + windows_destroy_clock(); +} |