Repository navigation
Expand file tree
/
Copy pathSDL_asyncio.c
More file actions
343 lines (293 loc) · 10.7 KB
/
Copy pathSDL_asyncio.c
File metadata and controls
343 lines (293 loc) · 10.7 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
/*
Simple DirectMedia Layer
Copyright (C) 1997-2026 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
#include "SDL_internal.h"
#include "SDL_sysasyncio.h"
#include "SDL_asyncio_c.h"
static const char *AsyncFileModeValid(const char *mode, bool *readonly)
{
static const struct { const char *valid; const char *with_binary; bool readonly; } mode_map[] = {
{ "r", "rb", true },
{ "w", "wb", false },
{ "r+","r+b", false },
{ "w+", "w+b", false }
};
for (int i = 0; i < SDL_arraysize(mode_map); i++) {
if (SDL_strcmp(mode, mode_map[i].valid) == 0) {
*readonly = mode_map[i].readonly;
return mode_map[i].with_binary;
}
}
*readonly = false;
return NULL;
}
SDL_AsyncIO *SDL_AsyncIOFromFile(const char *file, const char *mode)
{
CHECK_PARAM(!file) {
SDL_InvalidParamError("file");
return NULL;
}
CHECK_PARAM(!mode) {
SDL_InvalidParamError("mode");
return NULL;
}
bool readonly = false;
const char *binary_mode = AsyncFileModeValid(mode, &readonly);
if (!binary_mode) {
SDL_SetError("Unsupported file mode");
return NULL;
}
SDL_AsyncIO *asyncio = (SDL_AsyncIO *)SDL_calloc(1, sizeof(*asyncio));
if (!asyncio) {
return NULL;
}
asyncio->readonly = readonly;
asyncio->lock = SDL_CreateMutex();
if (!asyncio->lock) {
SDL_free(asyncio);
return NULL;
}
if (!SDL_SYS_AsyncIOFromFile(file, binary_mode, asyncio)) {
SDL_DestroyMutex(asyncio->lock);
SDL_free(asyncio);
return NULL;
}
return asyncio;
}
Sint64 SDL_GetAsyncIOSize(SDL_AsyncIO *asyncio)
{
CHECK_PARAM(!asyncio) {
SDL_InvalidParamError("asyncio");
return -1;
}
return asyncio->iface.size(asyncio->userdata);
}
static bool RequestAsyncIO(bool reading, SDL_AsyncIO *asyncio, void *ptr, Uint64 offset, Uint64 size, SDL_AsyncIOQueue *queue, void *userdata)
{
CHECK_PARAM(!asyncio) {
return SDL_InvalidParamError("asyncio");
}
CHECK_PARAM(!ptr) {
return SDL_InvalidParamError("ptr");
}
CHECK_PARAM(!queue) {
return SDL_InvalidParamError("queue");
}
SDL_AsyncIOTask *task = (SDL_AsyncIOTask *) SDL_calloc(1, sizeof (*task));
if (!task) {
return false;
}
task->asyncio = asyncio;
task->type = reading ? SDL_ASYNCIO_TASK_READ : SDL_ASYNCIO_TASK_WRITE;
task->offset = offset;
task->buffer = ptr;
task->requested_size = size;
task->app_userdata = userdata;
task->queue = queue;
SDL_LockMutex(asyncio->lock);
if (asyncio->closing) {
SDL_free(task);
SDL_UnlockMutex(asyncio->lock);
return SDL_SetError("SDL_AsyncIO is closing, can't start new tasks");
}
LINKED_LIST_PREPEND(task, asyncio->tasks, asyncio);
SDL_AddAtomicInt(&queue->tasks_inflight, 1);
SDL_UnlockMutex(asyncio->lock);
const bool queued = reading ? asyncio->iface.read(asyncio->userdata, task) : asyncio->iface.write(asyncio->userdata, task);
if (!queued) {
SDL_AddAtomicInt(&queue->tasks_inflight, -1);
SDL_LockMutex(asyncio->lock);
LINKED_LIST_UNLINK(task, asyncio);
SDL_UnlockMutex(asyncio->lock);
SDL_free(task);
task = NULL;
}
return (task != NULL);
}
bool SDL_ReadAsyncIO(SDL_AsyncIO *asyncio, void *ptr, Uint64 offset, Uint64 size, SDL_AsyncIOQueue *queue, void *userdata)
{
return RequestAsyncIO(true, asyncio, ptr, offset, size, queue, userdata);
}
bool SDL_WriteAsyncIO(SDL_AsyncIO *asyncio, void *ptr, Uint64 offset, Uint64 size, SDL_AsyncIOQueue *queue, void *userdata)
{
return RequestAsyncIO(false, asyncio, ptr, offset, size, queue, userdata);
}
bool SDL_CloseAsyncIO(SDL_AsyncIO *asyncio, bool flush, SDL_AsyncIOQueue *queue, void *userdata)
{
CHECK_PARAM(!asyncio) {
return SDL_InvalidParamError("asyncio");
}
CHECK_PARAM(!queue) {
return SDL_InvalidParamError("queue");
}
SDL_LockMutex(asyncio->lock);
if (asyncio->closing) {
SDL_UnlockMutex(asyncio->lock);
return SDL_SetError("Already closing");
}
SDL_AsyncIOTask *task = (SDL_AsyncIOTask *) SDL_calloc(1, sizeof (*task));
if (task) {
task->asyncio = asyncio;
task->type = SDL_ASYNCIO_TASK_CLOSE;
task->app_userdata = userdata;
task->queue = queue;
task->flush = flush;
asyncio->closing = task;
if (LINKED_LIST_START(asyncio->tasks, asyncio) == NULL) { // no tasks? Queue the close task now.
LINKED_LIST_PREPEND(task, asyncio->tasks, asyncio);
SDL_AddAtomicInt(&queue->tasks_inflight, 1);
if (!asyncio->iface.close(asyncio->userdata, task)) {
// uhoh, maybe they can try again later...?
SDL_AddAtomicInt(&queue->tasks_inflight, -1);
LINKED_LIST_UNLINK(task, asyncio);
SDL_free(task);
task = asyncio->closing = NULL;
}
}
}
SDL_UnlockMutex(asyncio->lock);
return (task != NULL);
}
SDL_AsyncIOQueue *SDL_CreateAsyncIOQueue(void)
{
SDL_AsyncIOQueue *queue = SDL_calloc(1, sizeof (*queue));
if (queue) {
SDL_SetAtomicInt(&queue->tasks_inflight, 0);
if (!SDL_SYS_CreateAsyncIOQueue(queue)) {
SDL_free(queue);
return NULL;
}
}
return queue;
}
static bool GetAsyncI
8000
OTaskOutcome(SDL_AsyncIOTask *task, SDL_AsyncIOOutcome *outcome)
{
if (!task || !outcome) {
return false;
}
SDL_AsyncIO *asyncio = task->asyncio;
SDL_zerop(outcome);
outcome->asyncio = asyncio->oneshot ? NULL : asyncio;
outcome->result = task->result;
outcome->type = task->type;
outcome->buffer = task->buffer;
outcome->offset = task->offset;
outcome->bytes_requested = task->requested_size;
outcome->bytes_transferred = task->result_size;
outcome->userdata = task->app_userdata;
// Take the completed task out of the SDL_AsyncIO that created it.
SDL_Mutex *lock = asyncio->lock;
SDL_LockMutex(lock);
LINKED_LIST_UNLINK(task, asyncio);
// see if it's time to queue a pending close request (close requested and no other pending tasks)
SDL_AsyncIOTask *closing = asyncio->closing;
if (closing && (task != closing) && (LINKED_LIST_START(asyncio->tasks, asyncio) == NULL)) {
LINKED_LIST_PREPEND(closing, asyncio->tasks, asyncio);
SDL_AddAtomicInt(&closing->queue->tasks_inflight, 1);
const bool async_close_task_was_queued = asyncio->iface.close(asyncio->userdata, closing);
SDL_assert(async_close_task_was_queued); // !!! FIXME: if this fails to queue the task, we're leaking resources!
if (!async_close_task_was_queued) {
SDL_AddAtomicInt(&closing->queue->tasks_inflight, -1);
}
}
SDL_UnlockMutex(lock);
// was this the result of a closing task? Finally destroy the asyncio.
bool retval = true;
if (closing && (task == closing)) {
if (asyncio->oneshot) {
retval = false; // don't send the close task results on to the app, just the read task for these.
}
asyncio->iface.destroy(asyncio->userdata);
SDL_DestroyMutex(asyncio->lock);
SDL_free(asyncio);
}
SDL_AddAtomicInt(&task->queue->tasks_inflight, -1);
SDL_free(task);
return retval;
}
bool SDL_GetAsyncIOResult(SDL_AsyncIOQueue *queue, SDL_AsyncIOOutcome *outcome)
{
if (!queue || !outcome) {
return false;
}
return GetAsyncIOTaskOutcome(queue->iface.get_results(queue->userdata), outcome);
}
bool SDL_WaitAsyncIOResult(SDL_AsyncIOQueue *queue, SDL_AsyncIOOutcome *outcome, Sint32 timeoutMS)
{
if (!queue || !outcome) {
return false;
}
return GetAsyncIOTaskOutcome(queue->iface.wait_results(queue->userdata, timeoutMS), outcome);
}
void SDL_SignalAsyncIOQueue(SDL_AsyncIOQueue *queue)
{
if (queue) {
queue->iface.signal(queue->userdata);
}
}
void SDL_DestroyAsyncIOQueue(SDL_AsyncIOQueue *queue)
{
if (queue) {
// block until any pending tasks complete.
while (SDL_GetAtomicInt(&queue->tasks_inflight) > 0) {
SDL_AsyncIOTask *task = queue->iface.wait_results(queue->userdata, -1);
if (task) {
if (task->asyncio->oneshot) {
SDL_free(task->buffer); // throw away the buffer from SDL_LoadFileAsync that will never be consumed/freed by app.
task->buffer = NULL;
}
SDL_AsyncIOOutcome outcome;
GetAsyncIOTaskOutcome(task, &outcome); // this frees the task, and does other upkeep.
}
}
queue->iface.destroy(queue->userdata);
SDL_free(queue);
}
}
void SDL_QuitAsyncIO(void)
{
SDL_SYS_QuitAsyncIO();
}
bool SDL_LoadFileAsync(const char *file, SDL_AsyncIOQueue *queue, void *userdata)
{
CHECK_PARAM(!file) {
return SDL_InvalidParamError("file");
}
CHECK_PARAM(!queue) {
return SDL_InvalidParamError("queue");
}
bool retval = false;
SDL_AsyncIO *asyncio = SDL_AsyncIOFromFile(file, "r");
if (asyncio) {
asyncio->>
Uint8 *ptr = NULL;
const Sint64 flen = SDL_GetAsyncIOSize(asyncio);
if (flen >= 0) {
// !!! FIXME: check if flen > address space, since it'll truncate and we'll just end up with an incomplete buffer or a crash.
ptr = (Uint8 *) SDL_malloc((size_t) (flen + 1)); // over-allocate by one so we can add a null-terminator.
if (ptr) {
ptr[flen] = '\0';
retval = SDL_ReadAsyncIO(asyncio, ptr, 0, (Uint64) flen, queue, userdata);
if (!retval) {
SDL_free(ptr);
}
}
}
SDL_CloseAsyncIO(asyncio, false, queue, userdata); // if this fails, we'll have a resource leak, but this would already be a dramatic system failure.
}
return retval;
}