1 /*----------------------------------------------------------------------------
2 *
3 * File:
4 * eas_hostmm.c
5 *
6 * Contents and purpose:
7 * This file contains the host wrapper functions for stdio, stdlib, etc.
8 * This is a sample version that reads from a filedescriptor.
9 * The file locator (EAS_FILE_LOCATOR) handle passed to
10 * HWOpenFile is the same one that is passed to EAS_OpenFile.
11 *
12 * Modify this file to suit the needs of your particular system.
13 *
14 * EAS_MAX_FILE_HANDLES sets the maximum number of MIDI streams within
15 * a MIDI type 1 file that can be played.
16 *
17 * EAS_HW_FILE is a structure to support the file I/O functions. It
18 * comprises the file descriptor, the file read pointer, and
19 * the dup flag, which when set, indicates that the file handle has
20 * been duplicated, and offset and length within the file.
21 *
22 * Copyright 2005 Sonic Network Inc.
23
24 * Licensed under the Apache License, Version 2.0 (the "License");
25 * you may not use this file except in compliance with the License.
26 * You may obtain a copy of the License at
27 *
28 * http://www.apache.org/licenses/LICENSE-2.0
29 *
30 * Unless required by applicable law or agreed to in writing, software
31 * distributed under the License is distributed on an "AS IS" BASIS,
32 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
33 * See the License for the specific language governing permissions and
34 * limitations under the License.
35 *
36 *----------------------------------------------------------------------------
37 * Revision Control:
38 * $Revision: 795 $
39 * $Date: 2007-08-01 00:14:45 -0700 (Wed, 01 Aug 2007) $
40 *----------------------------------------------------------------------------
41 */
42
43 #ifdef _lint
44 #include "lint_stdlib.h"
45 #else
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <unistd.h>
50 #include <sys/types.h>
51 #include <sys/stat.h>
52 #include <fcntl.h>
53 #include <limits.h>
54 #include <sys/mman.h>
55 #include <errno.h>
56 #include <signal.h>
57 #define LOG_TAG "Sonivox"
58 #include <utils/Log.h>
59 #include <media/MediaPlayerInterface.h>
60 #endif
61
62 #include "eas_host.h"
63
64 /* Only for debugging LED, vibrate, and backlight functions */
65 #include "eas_report.h"
66
67 /* this module requires dynamic memory support */
68 #ifdef _STATIC_MEMORY
69 #error "eas_hostmm.c requires the dynamic memory model!\n"
70 #endif
71
72 #ifndef EAS_MAX_FILE_HANDLES
73 // 100 max file handles == 3 * (nb tracks(32) + 1 for the segment) + 1 for jet file
74 // 3 == 1(playing segment) + 1(prepared segment)
75 // + 1(after end of playing segment, before files closed)
76 #define EAS_MAX_FILE_HANDLES 100
77 #endif
78
79 /*
80 * this structure and the related function are here
81 * to support the ability to create duplicate handles
82 * and buffering it in memory. If your system uses
83 * in-memory resources, you can eliminate the calls
84 * to malloc and free, the dup flag, and simply track
85 * the file size and read position.
86 */
87 typedef struct eas_hw_file_tag
88 {
89 EAS_I32 fileSize;
90 EAS_I32 filePos;
91 EAS_BOOL dup;
92 int fd;
93 EAS_I32 offset;
94 } EAS_HW_FILE;
95
96 typedef struct eas_hw_inst_data_tag
97 {
98 EAS_HW_FILE files[EAS_MAX_FILE_HANDLES];
99 } EAS_HW_INST_DATA;
100
101 pthread_key_t EAS_sigbuskey;
102
103 /*----------------------------------------------------------------------------
104 * EAS_HWInit
105 *
106 * Initialize host wrapper interface
107 *
108 *----------------------------------------------------------------------------
109 */
EAS_HWInit(EAS_HW_DATA_HANDLE * pHWInstData)110 EAS_RESULT EAS_HWInit (EAS_HW_DATA_HANDLE *pHWInstData)
111 {
112 EAS_HW_FILE *file;
113 int i;
114
115 /* need to track file opens for duplicate handles */
116 *pHWInstData = malloc(sizeof(EAS_HW_INST_DATA));
117 if (!(*pHWInstData))
118 return EAS_ERROR_MALLOC_FAILED;
119
120 EAS_HWMemSet(*pHWInstData, 0, sizeof(EAS_HW_INST_DATA));
121
122 file = (*pHWInstData)->files;
123 for (i = 0; i < EAS_MAX_FILE_HANDLES; i++)
124 {
125 file->fd = -1;
126 file++;
127 }
128
129
130 return EAS_SUCCESS;
131 }
132
133 /*----------------------------------------------------------------------------
134 * EAS_HWShutdown
135 *
136 * Shut down host wrapper interface
137 *
138 *----------------------------------------------------------------------------
139 */
EAS_HWShutdown(EAS_HW_DATA_HANDLE hwInstData)140 EAS_RESULT EAS_HWShutdown (EAS_HW_DATA_HANDLE hwInstData)
141 {
142
143 free(hwInstData);
144 return EAS_SUCCESS;
145 }
146
147 /*----------------------------------------------------------------------------
148 *
149 * EAS_HWMalloc
150 *
151 * Allocates dynamic memory
152 *
153 *----------------------------------------------------------------------------
154 */
155 /*lint -esym(715, hwInstData) hwInstData available for customer use */
EAS_HWMalloc(EAS_HW_DATA_HANDLE hwInstData,EAS_I32 size)156 void *EAS_HWMalloc (EAS_HW_DATA_HANDLE hwInstData, EAS_I32 size)
157 {
158 /* Since this whole library loves signed sizes, let's not let
159 * negative or 0 values through */
160 if (size <= 0)
161 return NULL;
162 return malloc((size_t) size);
163 }
164
165 /*----------------------------------------------------------------------------
166 *
167 * EAS_HWFree
168 *
169 * Frees dynamic memory
170 *
171 *----------------------------------------------------------------------------
172 */
173 /*lint -esym(715, hwInstData) hwInstData available for customer use */
EAS_HWFree(EAS_HW_DATA_HANDLE hwInstData,void * p)174 void EAS_HWFree (EAS_HW_DATA_HANDLE hwInstData, void *p)
175 {
176 free(p);
177 }
178
179 /*----------------------------------------------------------------------------
180 *
181 * EAS_HWMemCpy
182 *
183 * Copy memory wrapper
184 *
185 *----------------------------------------------------------------------------
186 */
EAS_HWMemCpy(void * dest,const void * src,EAS_I32 amount)187 void *EAS_HWMemCpy (void *dest, const void *src, EAS_I32 amount)
188 {
189 if (amount < 0) {
190 EAS_ReportEx(_EAS_SEVERITY_NOFILTER, 0x1a54b6e8, 0x00000004 , amount);
191 exit(255);
192 }
193 return memcpy(dest, src, (size_t) amount);
194 }
195
196 /*----------------------------------------------------------------------------
197 *
198 * EAS_HWMemSet
199 *
200 * Set memory wrapper
201 *
202 *----------------------------------------------------------------------------
203 */
EAS_HWMemSet(void * dest,int val,EAS_I32 amount)204 void *EAS_HWMemSet (void *dest, int val, EAS_I32 amount)
205 {
206 if (amount < 0) {
207 EAS_ReportEx(_EAS_SEVERITY_NOFILTER, 0x1a54b6e8, 0x00000005 , amount);
208 exit(255);
209 }
210 return memset(dest, val, (size_t) amount);
211 }
212
213 /*----------------------------------------------------------------------------
214 *
215 * EAS_HWMemCmp
216 *
217 * Compare memory wrapper
218 *
219 *----------------------------------------------------------------------------
220 */
EAS_HWMemCmp(const void * s1,const void * s2,EAS_I32 amount)221 EAS_I32 EAS_HWMemCmp (const void *s1, const void *s2, EAS_I32 amount)
222 {
223 if (amount < 0) {
224 EAS_ReportEx(_EAS_SEVERITY_NOFILTER, 0x1a54b6e8, 0x00000006 , amount);
225 exit(255);
226 }
227 return (EAS_I32) memcmp(s1, s2, (size_t) amount);
228 }
229
230 /*----------------------------------------------------------------------------
231 *
232 * EAS_HWOpenFile
233 *
234 * Open a file for read or write
235 *
236 *----------------------------------------------------------------------------
237 */
EAS_HWOpenFile(EAS_HW_DATA_HANDLE hwInstData,EAS_FILE_LOCATOR locator,EAS_FILE_HANDLE * pFile,EAS_FILE_MODE mode)238 EAS_RESULT EAS_HWOpenFile (EAS_HW_DATA_HANDLE hwInstData, EAS_FILE_LOCATOR locator, EAS_FILE_HANDLE *pFile, EAS_FILE_MODE mode)
239 {
240 EAS_HW_FILE *file;
241 int fd;
242 int i, temp;
243
244 /* set return value to NULL */
245 *pFile = NULL;
246
247 /* only support read mode at this time */
248 if (mode != EAS_FILE_READ)
249 return EAS_ERROR_INVALID_FILE_MODE;
250
251 /* find an empty entry in the file table */
252 file = hwInstData->files;
253 for (i = 0; i < EAS_MAX_FILE_HANDLES; i++)
254 {
255 /* is this slot being used? */
256 if (file->fd < 0)
257 {
258 if (locator->path) {
259 /* open the file */
260 if ((fd = open(locator->path, O_RDONLY)) < 0) {
261 return EAS_ERROR_FILE_OPEN_FAILED;
262 }
263 } else {
264 /* else file is already open */
265 fd = dup(locator->fd);
266 }
267
268 /* determine the file size */
269 if (locator->length == 0) {
270 if (lseek(fd, 0, SEEK_END) < 0) {
271 close(fd);
272 return EAS_ERROR_FILE_LENGTH;
273 }
274 if ((file->fileSize = lseek(fd, 0, SEEK_CUR)) == -1L) {
275 close(fd);
276 return EAS_ERROR_FILE_LENGTH;
277 }
278 }
279
280 // file size was passed in
281 else {
282 file->fileSize = (EAS_I32) locator->length;
283 }
284
285 file->fd = fd;
286 file->offset = locator->offset;
287
288 /* initialize some values */
289 file->filePos = 0;
290 file->dup = EAS_FALSE;
291
292 *pFile = file;
293 return EAS_SUCCESS;
294 }
295 file++;
296 }
297
298 /* too many open files */
299 return EAS_ERROR_MAX_FILES_OPEN;
300 }
301
302
303 /*----------------------------------------------------------------------------
304 *
305 * EAS_HWReadFile
306 *
307 * Read data from a file
308 *
309 *----------------------------------------------------------------------------
310 */
311 /*lint -esym(715, hwInstData) hwInstData available for customer use */
EAS_HWReadFile(EAS_HW_DATA_HANDLE hwInstData,EAS_FILE_HANDLE file,void * pBuffer,EAS_I32 n,EAS_I32 * pBytesRead)312 EAS_RESULT EAS_HWReadFile (EAS_HW_DATA_HANDLE hwInstData, EAS_FILE_HANDLE file, void *pBuffer, EAS_I32 n, EAS_I32 *pBytesRead)
313 {
314 EAS_I32 count;
315
316 /* make sure we have a valid handle */
317 if (file->fd < 0)
318 return EAS_ERROR_INVALID_HANDLE;
319
320 if (n < 0)
321 return EAS_EOF;
322
323 /* calculate the bytes to read */
324 count = file->fileSize - file->filePos;
325 if (n < count)
326 count = n;
327 if (count < 0)
328 return EAS_EOF;
329
330 /* copy the data to the requested location, and advance the pointer */
331 if (count) {
332 lseek(file->fd, file->filePos + file->offset, SEEK_SET);
333 count = read(file->fd, pBuffer, count);
334 }
335 file->filePos += count;
336 *pBytesRead = count;
337
338 /* were n bytes read? */
339 if (count!= n)
340 return EAS_EOF;
341 return EAS_SUCCESS;
342 }
343
344 /*----------------------------------------------------------------------------
345 *
346 * EAS_HWGetByte
347 *
348 * Read a byte from a file
349 *
350 *----------------------------------------------------------------------------
351 */
352 /*lint -esym(715, hwInstData) hwInstData available for customer use */
EAS_HWGetByte(EAS_HW_DATA_HANDLE hwInstData,EAS_FILE_HANDLE file,void * p)353 EAS_RESULT EAS_HWGetByte (EAS_HW_DATA_HANDLE hwInstData, EAS_FILE_HANDLE file, void *p)
354 {
355 EAS_I32 numread;
356 return EAS_HWReadFile(hwInstData, file, p, 1, &numread);
357 }
358
359 /*----------------------------------------------------------------------------
360 *
361 * EAS_HWGetWord
362 *
363 * Read a 16 bit word from a file
364 *
365 *----------------------------------------------------------------------------
366 */
367 /*lint -esym(715, hwInstData) hwInstData available for customer use */
EAS_HWGetWord(EAS_HW_DATA_HANDLE hwInstData,EAS_FILE_HANDLE file,void * p,EAS_BOOL msbFirst)368 EAS_RESULT EAS_HWGetWord (EAS_HW_DATA_HANDLE hwInstData, EAS_FILE_HANDLE file, void *p, EAS_BOOL msbFirst)
369 {
370 EAS_RESULT result;
371 EAS_U8 c1, c2;
372
373 /* read 2 bytes from the file */
374 if ((result = EAS_HWGetByte(hwInstData, file, &c1)) != EAS_SUCCESS)
375 return result;
376 if ((result = EAS_HWGetByte(hwInstData, file, &c2)) != EAS_SUCCESS)
377 return result;
378
379 /* order them as requested */
380 if (msbFirst)
381 *((EAS_U16*) p) = ((EAS_U16) c1 << 8) | c2;
382 else
383 *((EAS_U16*) p) = ((EAS_U16) c2 << 8) | c1;
384
385 return EAS_SUCCESS;
386 }
387
388 /*----------------------------------------------------------------------------
389 *
390 * EAS_HWGetDWord
391 *
392 * Returns the current location in the file
393 *
394 *----------------------------------------------------------------------------
395 */
396 /*lint -esym(715, hwInstData) hwInstData available for customer use */
EAS_HWGetDWord(EAS_HW_DATA_HANDLE hwInstData,EAS_FILE_HANDLE file,void * p,EAS_BOOL msbFirst)397 EAS_RESULT EAS_HWGetDWord (EAS_HW_DATA_HANDLE hwInstData, EAS_FILE_HANDLE file, void *p, EAS_BOOL msbFirst)
398 {
399 EAS_RESULT result;
400 EAS_U8 c1, c2,c3,c4;
401
402 /* read 4 bytes from the file */
403 if ((result = EAS_HWGetByte(hwInstData, file, &c1)) != EAS_SUCCESS)
404 return result;
405 if ((result = EAS_HWGetByte(hwInstData, file, &c2)) != EAS_SUCCESS)
406 return result;
407 if ((result = EAS_HWGetByte(hwInstData, file, &c3)) != EAS_SUCCESS)
408 return result;
409 if ((result = EAS_HWGetByte(hwInstData, file, &c4)) != EAS_SUCCESS)
410 return result;
411
412 /* order them as requested */
413 if (msbFirst)
414 *((EAS_U32*) p) = ((EAS_U32) c1 << 24) | ((EAS_U32) c2 << 16) | ((EAS_U32) c3 << 8) | c4;
415 else
416 *((EAS_U32*) p)= ((EAS_U32) c4 << 24) | ((EAS_U32) c3 << 16) | ((EAS_U32) c2 << 8) | c1;
417
418 return EAS_SUCCESS;
419 }
420
421 /*----------------------------------------------------------------------------
422 *
423 * EAS_HWFilePos
424 *
425 * Returns the current location in the file
426 *
427 *----------------------------------------------------------------------------
428 */
429 /*lint -esym(715, hwInstData) hwInstData available for customer use */
EAS_HWFilePos(EAS_HW_DATA_HANDLE hwInstData,EAS_FILE_HANDLE file,EAS_I32 * pPosition)430 EAS_RESULT EAS_HWFilePos (EAS_HW_DATA_HANDLE hwInstData, EAS_FILE_HANDLE file, EAS_I32 *pPosition)
431 {
432
433 /* make sure we have a valid handle */
434 if (file->fd < 0)
435 return EAS_ERROR_INVALID_HANDLE;
436
437 *pPosition = file->filePos;
438 return EAS_SUCCESS;
439 } /* end EAS_HWFilePos */
440
441 /*----------------------------------------------------------------------------
442 *
443 * EAS_HWFileSeek
444 *
445 * Seek to a specific location in the file
446 *
447 *----------------------------------------------------------------------------
448 */
449 /*lint -esym(715, hwInstData) hwInstData available for customer use */
EAS_HWFileSeek(EAS_HW_DATA_HANDLE hwInstData,EAS_FILE_HANDLE file,EAS_I32 position)450 EAS_RESULT EAS_HWFileSeek (EAS_HW_DATA_HANDLE hwInstData, EAS_FILE_HANDLE file, EAS_I32 position)
451 {
452
453 /* make sure we have a valid handle */
454 if (file->fd < 0)
455 return EAS_ERROR_INVALID_HANDLE;
456
457 /* validate new position */
458 if ((position < 0) || (position > file->fileSize))
459 return EAS_ERROR_FILE_SEEK;
460
461 /* save new position */
462 file->filePos = position;
463 return EAS_SUCCESS;
464 }
465
466 /*----------------------------------------------------------------------------
467 *
468 * EAS_HWFileSeekOfs
469 *
470 * Seek forward or back relative to the current position
471 *
472 *----------------------------------------------------------------------------
473 */
474 /*lint -esym(715, hwInstData) hwInstData available for customer use */
EAS_HWFileSeekOfs(EAS_HW_DATA_HANDLE hwInstData,EAS_FILE_HANDLE file,EAS_I32 position)475 EAS_RESULT EAS_HWFileSeekOfs (EAS_HW_DATA_HANDLE hwInstData, EAS_FILE_HANDLE file, EAS_I32 position)
476 {
477
478 /* make sure we have a valid handle */
479 if (file->fd < 0)
480 return EAS_ERROR_INVALID_HANDLE;
481
482 /* determine the file position */
483 position += file->filePos;
484 if ((position < 0) || (position > file->fileSize))
485 return EAS_ERROR_FILE_SEEK;
486
487 /* save new position */
488 file->filePos = position;
489 return EAS_SUCCESS;
490 }
491
492 /*----------------------------------------------------------------------------
493 *
494 * EAS_HWFileLength
495 *
496 * Return the file length
497 *
498 *----------------------------------------------------------------------------
499 */
500 /*lint -esym(715, hwInstData) hwInstData available for customer use */
EAS_HWFileLength(EAS_HW_DATA_HANDLE hwInstData,EAS_FILE_HANDLE file,EAS_I32 * pLength)501 EAS_RESULT EAS_HWFileLength (EAS_HW_DATA_HANDLE hwInstData, EAS_FILE_HANDLE file, EAS_I32 *pLength)
502 {
503
504 /* make sure we have a valid handle */
505 if (file->fd < 0)
506 return EAS_ERROR_INVALID_HANDLE;
507
508 *pLength = file->fileSize;
509 return EAS_SUCCESS;
510 }
511
512 /*----------------------------------------------------------------------------
513 *
514 * EAS_HWDupHandle
515 *
516 * Duplicate a file handle
517 *
518 *----------------------------------------------------------------------------
519 */
EAS_HWDupHandle(EAS_HW_DATA_HANDLE hwInstData,EAS_FILE_HANDLE file,EAS_FILE_HANDLE * pDupFile)520 EAS_RESULT EAS_HWDupHandle (EAS_HW_DATA_HANDLE hwInstData, EAS_FILE_HANDLE file, EAS_FILE_HANDLE *pDupFile)
521 {
522 EAS_HW_FILE *dupFile;
523 int i;
524
525 /* make sure we have a valid handle */
526 if (file->fd < 0)
527 return EAS_ERROR_INVALID_HANDLE;
528
529 /* find an empty entry in the file table */
530 dupFile = hwInstData->files;
531 for (i = 0; i < EAS_MAX_FILE_HANDLES; i++)
532 {
533 /* is this slot being used? */
534 if (dupFile->fd < 0)
535 {
536 /* copy info from the handle to be duplicated */
537 dupFile->filePos = file->filePos;
538 dupFile->fileSize = file->fileSize;
539 dupFile->fd = file->fd;
540 dupFile->offset = file->offset;
541
542 /* set the duplicate handle flag */
543 dupFile->dup = file->dup = EAS_TRUE;
544
545 *pDupFile = dupFile;
546 return EAS_SUCCESS;
547 }
548 dupFile++;
549 }
550
551 /* too many open files */
552 return EAS_ERROR_MAX_FILES_OPEN;
553 }
554
555 /*----------------------------------------------------------------------------
556 *
557 * EAS_HWClose
558 *
559 * Wrapper for fclose function
560 *
561 *----------------------------------------------------------------------------
562 */
EAS_HWCloseFile(EAS_HW_DATA_HANDLE hwInstData,EAS_FILE_HANDLE file1)563 EAS_RESULT EAS_HWCloseFile (EAS_HW_DATA_HANDLE hwInstData, EAS_FILE_HANDLE file1)
564 {
565 EAS_HW_FILE *file2,*dupFile;
566 int i;
567
568
569 /* make sure we have a valid handle */
570 if (file1->fd < 0)
571 return EAS_ERROR_INVALID_HANDLE;
572
573 /* check for duplicate handle */
574 if (file1->dup)
575 {
576 dupFile = NULL;
577 file2 = hwInstData->files;
578 for (i = 0; i < EAS_MAX_FILE_HANDLES; i++)
579 {
580 /* check for duplicate */
581 if ((file1 != file2) && (file2->fd == file1->fd))
582 {
583 /* is there more than one duplicate? */
584 if (dupFile != NULL)
585 {
586 /* clear this entry and return */
587 file1->fd = -1;
588 return EAS_SUCCESS;
589 }
590
591 /* this is the first duplicate found */
592 else
593 dupFile = file2;
594 }
595 file2++;
596 }
597
598 /* there is only one duplicate, clear the dup flag */
599 if (dupFile)
600 dupFile->dup = EAS_FALSE;
601 else
602 /* if we get here, there's a serious problem */
603 return EAS_ERROR_HANDLE_INTEGRITY;
604
605 /* clear this entry and return */
606 file1->fd = -1;
607 return EAS_SUCCESS;
608 }
609
610 /* no duplicates - close the file */
611 close(file1->fd);
612 /* clear this entry and return */
613 file1->fd = -1;
614 return EAS_SUCCESS;
615 }
616
617 /*----------------------------------------------------------------------------
618 *
619 * EAS_HWVibrate
620 *
621 * Turn on/off vibrate function
622 *
623 *----------------------------------------------------------------------------
624 */
625 /*lint -esym(715, hwInstData) hwInstData available for customer use */
EAS_HWVibrate(EAS_HW_DATA_HANDLE hwInstData,EAS_BOOL state)626 EAS_RESULT EAS_HWVibrate (EAS_HW_DATA_HANDLE hwInstData, EAS_BOOL state)
627 {
628 EAS_ReportEx(_EAS_SEVERITY_NOFILTER, 0x1a54b6e8, 0x00000001 , state);
629 return EAS_SUCCESS;
630 } /* end EAS_HWVibrate */
631
632 /*----------------------------------------------------------------------------
633 *
634 * EAS_HWLED
635 *
636 * Turn on/off LED
637 *
638 *----------------------------------------------------------------------------
639 */
640 /*lint -esym(715, hwInstData) hwInstData available for customer use */
EAS_HWLED(EAS_HW_DATA_HANDLE hwInstData,EAS_BOOL state)641 EAS_RESULT EAS_HWLED (EAS_HW_DATA_HANDLE hwInstData, EAS_BOOL state)
642 {
643 EAS_ReportEx(_EAS_SEVERITY_NOFILTER, 0x1a54b6e8, 0x00000002 , state);
644 return EAS_SUCCESS;
645 }
646
647 /*----------------------------------------------------------------------------
648 *
649 * EAS_HWBackLight
650 *
651 * Turn on/off backlight
652 *
653 *----------------------------------------------------------------------------
654 */
655 /*lint -esym(715, hwInstData) hwInstData available for customer use */
EAS_HWBackLight(EAS_HW_DATA_HANDLE hwInstData,EAS_BOOL state)656 EAS_RESULT EAS_HWBackLight (EAS_HW_DATA_HANDLE hwInstData, EAS_BOOL state)
657 {
658 EAS_ReportEx(_EAS_SEVERITY_NOFILTER, 0x1a54b6e8, 0x00000003 , state);
659 return EAS_SUCCESS;
660 }
661
662 /*----------------------------------------------------------------------------
663 *
664 * EAS_HWYield
665 *
666 * This function is called periodically by the EAS library to give the
667 * host an opportunity to allow other tasks to run. There are two ways to
668 * use this call:
669 *
670 * If you have a multi-tasking OS, you can call the yield function in the
671 * OS to allow other tasks to run. In this case, return EAS_FALSE to tell
672 * the EAS library to continue processing when control returns from this
673 * function.
674 *
675 * If tasks run in a single thread by sequential function calls (sometimes
676 * call a "commutator loop"), return EAS_TRUE to cause the EAS Library to
677 * return to the caller. Be sure to check the number of bytes rendered
678 * before passing the audio buffer to the codec - it may not be filled.
679 * The next call to EAS_Render will continue processing until the buffer
680 * has been filled.
681 *
682 *----------------------------------------------------------------------------
683 */
684 /*lint -esym(715, hwInstData) hwInstData available for customer use */
EAS_HWYield(EAS_HW_DATA_HANDLE hwInstData)685 EAS_BOOL EAS_HWYield (EAS_HW_DATA_HANDLE hwInstData)
686 {
687 /* put your code here */
688 return EAS_FALSE;
689 }
690
691