• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2012 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include <system/audio.h>
18 #include <audio_utils/sndfile.h>
19 #include <audio_utils/primitives.h>
20 #ifdef HAVE_STDERR
21 #include <stdio.h>
22 #endif
23 #include <string.h>
24 #include <errno.h>
25 
26 #define WAVE_FORMAT_PCM         1
27 #define WAVE_FORMAT_IEEE_FLOAT  3
28 #define WAVE_FORMAT_EXTENSIBLE  0xFFFE
29 
30 struct SNDFILE_ {
31     int mode;
32     uint8_t *temp;  // realloc buffer used for shrinking 16 bits to 8 bits and byte-swapping
33     FILE *stream;
34     size_t bytesPerFrame;
35     size_t remaining;   // frames unread for SFM_READ, frames written for SFM_WRITE
36     SF_INFO info;
37 };
38 
little2u(unsigned char * ptr)39 static unsigned little2u(unsigned char *ptr)
40 {
41     return (ptr[1] << 8) + ptr[0];
42 }
43 
little4u(unsigned char * ptr)44 static unsigned little4u(unsigned char *ptr)
45 {
46     return (ptr[3] << 24) + (ptr[2] << 16) + (ptr[1] << 8) + ptr[0];
47 }
48 
isLittleEndian(void)49 static int isLittleEndian(void)
50 {
51     static const short one = 1;
52     return *((const char *) &one) == 1;
53 }
54 
55 // "swab" conflicts with OS X <string.h>
my_swab(short * ptr,size_t numToSwap)56 static void my_swab(short *ptr, size_t numToSwap)
57 {
58     while (numToSwap > 0) {
59         *ptr = little2u((unsigned char *) ptr);
60         --numToSwap;
61         ++ptr;
62     }
63 }
64 
sf_open_read(const char * path,SF_INFO * info)65 static SNDFILE *sf_open_read(const char *path, SF_INFO *info)
66 {
67     FILE *stream = fopen(path, "rb");
68     if (stream == NULL) {
69 #ifdef HAVE_STDERR
70         fprintf(stderr, "fopen %s failed errno %d\n", path, errno);
71 #endif
72         return NULL;
73     }
74 
75     SNDFILE *handle = (SNDFILE *) malloc(sizeof(SNDFILE));
76     handle->mode = SFM_READ;
77     handle->temp = NULL;
78     handle->stream = stream;
79     handle->info.format = SF_FORMAT_WAV;
80 
81     // don't attempt to parse all valid forms, just the most common ones
82     unsigned char wav[12];
83     size_t actual;
84     actual = fread(wav, sizeof(char), sizeof(wav), stream);
85     if (actual < 12) {
86 #ifdef HAVE_STDERR
87         fprintf(stderr, "actual %zu < 44\n", actual);
88 #endif
89         goto close;
90     }
91     if (memcmp(wav, "RIFF", 4)) {
92 #ifdef HAVE_STDERR
93         fprintf(stderr, "wav != RIFF\n");
94 #endif
95         goto close;
96     }
97     unsigned riffSize = little4u(&wav[4]);
98     if (riffSize < 4) {
99 #ifdef HAVE_STDERR
100         fprintf(stderr, "riffSize %u < 4\n", riffSize);
101 #endif
102         goto close;
103     }
104     if (memcmp(&wav[8], "WAVE", 4)) {
105 #ifdef HAVE_STDERR
106         fprintf(stderr, "missing WAVE\n");
107 #endif
108         goto close;
109     }
110     size_t remaining = riffSize - 4;
111     int hadFmt = 0;
112     int hadData = 0;
113     long dataTell = 0L;
114     while (remaining >= 8) {
115         unsigned char chunk[8];
116         actual = fread(chunk, sizeof(char), sizeof(chunk), stream);
117         if (actual != sizeof(chunk)) {
118 #ifdef HAVE_STDERR
119             fprintf(stderr, "actual %zu != %zu\n", actual, sizeof(chunk));
120 #endif
121             goto close;
122         }
123         remaining -= 8;
124         unsigned chunkSize = little4u(&chunk[4]);
125         if (chunkSize > remaining) {
126 #ifdef HAVE_STDERR
127             fprintf(stderr, "chunkSize %u > remaining %zu\n", chunkSize, remaining);
128 #endif
129             goto close;
130         }
131         if (!memcmp(&chunk[0], "fmt ", 4)) {
132             if (hadFmt) {
133 #ifdef HAVE_STDERR
134                 fprintf(stderr, "multiple fmt\n");
135 #endif
136                 goto close;
137             }
138             if (chunkSize < 2) {
139 #ifdef HAVE_STDERR
140                 fprintf(stderr, "chunkSize %u < 2\n", chunkSize);
141 #endif
142                 goto close;
143             }
144             unsigned char fmt[40];
145             actual = fread(fmt, sizeof(char), 2, stream);
146             if (actual != 2) {
147 #ifdef HAVE_STDERR
148                 fprintf(stderr, "actual %zu != 2\n", actual);
149 #endif
150                 goto close;
151             }
152             unsigned format = little2u(&fmt[0]);
153             size_t minSize = 0;
154             switch (format) {
155             case WAVE_FORMAT_PCM:
156             case WAVE_FORMAT_IEEE_FLOAT:
157                 minSize = 16;
158                 break;
159             case WAVE_FORMAT_EXTENSIBLE:
160                 minSize = 40;
161                 break;
162             default:
163 #ifdef HAVE_STDERR
164                 fprintf(stderr, "unsupported format %u\n", format);
165 #endif
166                 goto close;
167             }
168             if (chunkSize < minSize) {
169 #ifdef HAVE_STDERR
170                 fprintf(stderr, "chunkSize %u < minSize %zu\n", chunkSize, minSize);
171 #endif
172                 goto close;
173             }
174             actual = fread(&fmt[2], sizeof(char), minSize - 2, stream);
175             if (actual != minSize - 2) {
176 #ifdef HAVE_STDERR
177                 fprintf(stderr, "actual %zu != %zu\n", actual, minSize - 16);
178 #endif
179                 goto close;
180             }
181             if (chunkSize > minSize) {
182                 fseek(stream, (long) (chunkSize - minSize), SEEK_CUR);
183             }
184             unsigned channels = little2u(&fmt[2]);
185             if ((channels < 1) || (channels > FCC_LIMIT)) {
186 #ifdef HAVE_STDERR
187                 fprintf(stderr, "unsupported channels %u\n", channels);
188 #endif
189                 goto close;
190             }
191             unsigned samplerate = little4u(&fmt[4]);
192             if (samplerate == 0) {
193 #ifdef HAVE_STDERR
194                 fprintf(stderr, "samplerate %u == 0\n", samplerate);
195 #endif
196                 goto close;
197             }
198             // ignore byte rate
199             // ignore block alignment
200             unsigned bitsPerSample = little2u(&fmt[14]);
201             if (bitsPerSample != 8 && bitsPerSample != 16 && bitsPerSample != 24 &&
202                     bitsPerSample != 32) {
203 #ifdef HAVE_STDERR
204                 fprintf(stderr, "bitsPerSample %u != 8 or 16 or 24 or 32\n", bitsPerSample);
205 #endif
206                 goto close;
207             }
208             unsigned bytesPerFrame = (bitsPerSample >> 3) * channels;
209             handle->bytesPerFrame = bytesPerFrame;
210             handle->info.samplerate = samplerate;
211             handle->info.channels = channels;
212             switch (bitsPerSample) {
213             case 8:
214                 handle->info.format |= SF_FORMAT_PCM_U8;
215                 break;
216             case 16:
217                 handle->info.format |= SF_FORMAT_PCM_16;
218                 break;
219             case 24:
220                 handle->info.format |= SF_FORMAT_PCM_24;
221                 break;
222             case 32:
223                 if (format == WAVE_FORMAT_IEEE_FLOAT)
224                     handle->info.format |= SF_FORMAT_FLOAT;
225                 else
226                     handle->info.format |= SF_FORMAT_PCM_32;
227                 break;
228             }
229             hadFmt = 1;
230         } else if (!memcmp(&chunk[0], "data", 4)) {
231             if (!hadFmt) {
232 #ifdef HAVE_STDERR
233                 fprintf(stderr, "data not preceded by fmt\n");
234 #endif
235                 goto close;
236             }
237             if (hadData) {
238 #ifdef HAVE_STDERR
239                 fprintf(stderr, "multiple data\n");
240 #endif
241                 goto close;
242             }
243             handle->remaining = chunkSize / handle->bytesPerFrame;
244             handle->info.frames = handle->remaining;
245             dataTell = ftell(stream);
246             if (chunkSize > 0) {
247                 fseek(stream, (long) chunkSize, SEEK_CUR);
248             }
249             hadData = 1;
250         } else if (!memcmp(&chunk[0], "fact", 4)) {
251             // ignore fact
252             if (chunkSize > 0) {
253                 fseek(stream, (long) chunkSize, SEEK_CUR);
254             }
255         } else {
256             // ignore unknown chunk
257 #ifdef HAVE_STDERR
258             fprintf(stderr, "ignoring unknown chunk %c%c%c%c\n",
259                     chunk[0], chunk[1], chunk[2], chunk[3]);
260 #endif
261             if (chunkSize > 0) {
262                 fseek(stream, (long) chunkSize, SEEK_CUR);
263             }
264         }
265         remaining -= chunkSize;
266     }
267     if (remaining > 0) {
268 #ifdef HAVE_STDERR
269         fprintf(stderr, "partial chunk at end of RIFF, remaining %zu\n", remaining);
270 #endif
271         goto close;
272     }
273     if (!hadData) {
274 #ifdef HAVE_STDERR
275         fprintf(stderr, "missing data\n");
276 #endif
277         goto close;
278     }
279     (void) fseek(stream, dataTell, SEEK_SET);
280     *info = handle->info;
281     return handle;
282 
283 close:
284     free(handle);
285     fclose(stream);
286     return NULL;
287 }
288 
write4u(unsigned char * ptr,unsigned u)289 static void write4u(unsigned char *ptr, unsigned u)
290 {
291     ptr[0] = u;
292     ptr[1] = u >> 8;
293     ptr[2] = u >> 16;
294     ptr[3] = u >> 24;
295 }
296 
sf_open_write(const char * path,SF_INFO * info)297 static SNDFILE *sf_open_write(const char *path, SF_INFO *info)
298 {
299     int sub = info->format & SF_FORMAT_SUBMASK;
300     if (!(
301             (info->samplerate > 0) &&
302             (info->channels > 0 && info->channels <= FCC_LIMIT) &&
303             (sub == SF_FORMAT_PCM_16 || sub == SF_FORMAT_PCM_U8 || sub == SF_FORMAT_FLOAT ||
304                 sub == SF_FORMAT_PCM_24 || sub == SF_FORMAT_PCM_32)
305           )) {
306         return NULL;
307     }
308     FILE *stream = fopen(path, "w+b");
309     if (stream == NULL) {
310 #ifdef HAVE_STDERR
311         fprintf(stderr, "fopen %s failed errno %d\n", path, errno);
312 #endif
313         return NULL;
314     }
315 
316     unsigned bitsPerSample;
317     switch (sub) {
318     case SF_FORMAT_PCM_16:
319         bitsPerSample = 16;
320         break;
321     case SF_FORMAT_PCM_U8:
322         bitsPerSample = 8;
323         break;
324     case SF_FORMAT_FLOAT:
325         bitsPerSample = 32;
326         break;
327     case SF_FORMAT_PCM_24:
328         bitsPerSample = 24;
329         break;
330     case SF_FORMAT_PCM_32:
331         bitsPerSample = 32;
332         break;
333     default:    // not reachable
334         bitsPerSample = 0;
335         break;
336     }
337     unsigned blockAlignment = (bitsPerSample >> 3) * info->channels;
338     if ((info->format & SF_FORMAT_TYPEMASK) == SF_FORMAT_WAV) {
339         unsigned char wav[58];
340         memset(wav, 0, sizeof(wav));
341         memcpy(wav, "RIFF", 4);
342         memcpy(&wav[8], "WAVEfmt ", 8);
343         if (sub == SF_FORMAT_FLOAT) {
344             wav[4] = 50;    // riffSize
345             wav[16] = 18;   // fmtSize
346             wav[20] = WAVE_FORMAT_IEEE_FLOAT;
347         } else {
348             wav[4] = 36;    // riffSize
349             wav[16] = 16;   // fmtSize
350             wav[20] = WAVE_FORMAT_PCM;
351         }
352         wav[22] = info->channels;
353         write4u(&wav[24], info->samplerate);
354         unsigned byteRate = info->samplerate * blockAlignment;
355         write4u(&wav[28], byteRate);
356         wav[32] = blockAlignment;
357         wav[34] = bitsPerSample;
358         size_t extra = 0;
359         if (sub == SF_FORMAT_FLOAT) {
360             memcpy(&wav[38], "fact", 4);
361             wav[42] = 4;
362             memcpy(&wav[50], "data", 4);
363             extra = 14;
364         } else
365             memcpy(&wav[36], "data", 4);
366         // dataSize is initially zero
367         (void) fwrite(wav, 44 + extra, 1, stream);
368     }
369     SNDFILE *handle = (SNDFILE *) malloc(sizeof(SNDFILE));
370     handle->mode = SFM_WRITE;
371     handle->temp = NULL;
372     handle->stream = stream;
373     handle->bytesPerFrame = blockAlignment;
374     handle->remaining = 0;
375     handle->info = *info;
376     return handle;
377 }
378 
sf_open(const char * path,int mode,SF_INFO * info)379 SNDFILE *sf_open(const char *path, int mode, SF_INFO *info)
380 {
381     if (path == NULL || info == NULL) {
382 #ifdef HAVE_STDERR
383         fprintf(stderr, "path=%p info=%p\n", path, info);
384 #endif
385         return NULL;
386     }
387     switch (mode) {
388     case SFM_READ:
389         return sf_open_read(path, info);
390     case SFM_WRITE:
391         return sf_open_write(path, info);
392     default:
393 #ifdef HAVE_STDERR
394         fprintf(stderr, "mode=%d\n", mode);
395 #endif
396         return NULL;
397     }
398 }
399 
sf_close(SNDFILE * handle)400 void sf_close(SNDFILE *handle)
401 {
402     if (handle == NULL)
403         return;
404     free(handle->temp);
405     if (handle->mode == SFM_WRITE) {
406         (void) fflush(handle->stream);
407         if ((handle->info.format & SF_FORMAT_TYPEMASK) == SF_FORMAT_WAV) {
408             rewind(handle->stream);
409             unsigned char wav[58];
410             size_t extra = (handle->info.format & SF_FORMAT_SUBMASK) == SF_FORMAT_FLOAT ? 14 : 0;
411             (void) fread(wav, 44 + extra, 1, handle->stream);
412             unsigned dataSize = handle->remaining * handle->bytesPerFrame;
413             write4u(&wav[4], dataSize + 36 + extra);    // riffSize
414             write4u(&wav[40 + extra], dataSize);        // dataSize
415             rewind(handle->stream);
416             (void) fwrite(wav, 44 + extra, 1, handle->stream);
417         }
418     }
419     (void) fclose(handle->stream);
420     free(handle);
421 }
422 
sf_readf_short(SNDFILE * handle,short * ptr,sf_count_t desiredFrames)423 sf_count_t sf_readf_short(SNDFILE *handle, short *ptr, sf_count_t desiredFrames)
424 {
425     if (handle == NULL || handle->mode != SFM_READ || ptr == NULL || !handle->remaining ||
426             desiredFrames <= 0) {
427         return 0;
428     }
429     if (handle->remaining < (size_t) desiredFrames) {
430         desiredFrames = handle->remaining;
431     }
432     // does not check for numeric overflow
433     size_t desiredBytes = desiredFrames * handle->bytesPerFrame;
434     size_t actualBytes;
435     void *temp = NULL;
436     unsigned format = handle->info.format & SF_FORMAT_SUBMASK;
437     if (format == SF_FORMAT_PCM_32 || format == SF_FORMAT_FLOAT || format == SF_FORMAT_PCM_24) {
438         temp = malloc(desiredBytes);
439         actualBytes = fread(temp, sizeof(char), desiredBytes, handle->stream);
440     } else {
441         actualBytes = fread(ptr, sizeof(char), desiredBytes, handle->stream);
442     }
443     size_t actualFrames = actualBytes / handle->bytesPerFrame;
444     handle->remaining -= actualFrames;
445     switch (format) {
446     case SF_FORMAT_PCM_U8:
447         memcpy_to_i16_from_u8(ptr, (unsigned char *) ptr, actualFrames * handle->info.channels);
448         break;
449     case SF_FORMAT_PCM_16:
450         if (!isLittleEndian())
451             my_swab(ptr, actualFrames * handle->info.channels);
452         break;
453     case SF_FORMAT_PCM_32:
454         memcpy_to_i16_from_i32(ptr, (const int *) temp, actualFrames * handle->info.channels);
455         free(temp);
456         break;
457     case SF_FORMAT_FLOAT:
458         memcpy_to_i16_from_float(ptr, (const float *) temp, actualFrames * handle->info.channels);
459         free(temp);
460         break;
461     case SF_FORMAT_PCM_24:
462         memcpy_to_i16_from_p24(ptr, (const uint8_t *) temp, actualFrames * handle->info.channels);
463         free(temp);
464         break;
465     default:
466         memset(ptr, 0, actualFrames * handle->info.channels * sizeof(short));
467         break;
468     }
469     return actualFrames;
470 }
471 
sf_readf_float(SNDFILE * handle,float * ptr,sf_count_t desiredFrames)472 sf_count_t sf_readf_float(SNDFILE *handle, float *ptr, sf_count_t desiredFrames)
473 {
474     if (handle == NULL || handle->mode != SFM_READ || ptr == NULL || !handle->remaining ||
475             desiredFrames <= 0) {
476         return 0;
477     }
478     if (handle->remaining < (size_t) desiredFrames) {
479         desiredFrames = handle->remaining;
480     }
481     // does not check for numeric overflow
482     size_t desiredBytes = desiredFrames * handle->bytesPerFrame;
483     size_t actualBytes;
484     void *temp = NULL;
485     unsigned format = handle->info.format & SF_FORMAT_SUBMASK;
486     if (format == SF_FORMAT_PCM_16 || format == SF_FORMAT_PCM_U8 || format == SF_FORMAT_PCM_24) {
487         temp = malloc(desiredBytes);
488         actualBytes = fread(temp, sizeof(char), desiredBytes, handle->stream);
489     } else {
490         actualBytes = fread(ptr, sizeof(char), desiredBytes, handle->stream);
491     }
492     size_t actualFrames = actualBytes / handle->bytesPerFrame;
493     handle->remaining -= actualFrames;
494     switch (format) {
495     case SF_FORMAT_PCM_U8:
496         memcpy_to_float_from_u8(ptr, (const unsigned char *) temp,
497                 actualFrames * handle->info.channels);
498         free(temp);
499         break;
500     case SF_FORMAT_PCM_16:
501         memcpy_to_float_from_i16(ptr, (const short *) temp, actualFrames * handle->info.channels);
502         free(temp);
503         break;
504     case SF_FORMAT_PCM_32:
505         memcpy_to_float_from_i32(ptr, (const int *) ptr, actualFrames * handle->info.channels);
506         break;
507     case SF_FORMAT_FLOAT:
508         break;
509     case SF_FORMAT_PCM_24:
510         memcpy_to_float_from_p24(ptr, (const uint8_t *) temp, actualFrames * handle->info.channels);
511         free(temp);
512         break;
513     default:
514         memset(ptr, 0, actualFrames * handle->info.channels * sizeof(float));
515         break;
516     }
517     return actualFrames;
518 }
519 
sf_readf_int(SNDFILE * handle,int * ptr,sf_count_t desiredFrames)520 sf_count_t sf_readf_int(SNDFILE *handle, int *ptr, sf_count_t desiredFrames)
521 {
522     if (handle == NULL || handle->mode != SFM_READ || ptr == NULL || !handle->remaining ||
523             desiredFrames <= 0) {
524         return 0;
525     }
526     if (handle->remaining < (size_t) desiredFrames) {
527         desiredFrames = handle->remaining;
528     }
529     // does not check for numeric overflow
530     size_t desiredBytes = desiredFrames * handle->bytesPerFrame;
531     void *temp = NULL;
532     unsigned format = handle->info.format & SF_FORMAT_SUBMASK;
533     size_t actualBytes;
534     if (format == SF_FORMAT_PCM_16 || format == SF_FORMAT_PCM_U8 || format == SF_FORMAT_PCM_24) {
535         temp = malloc(desiredBytes);
536         actualBytes = fread(temp, sizeof(char), desiredBytes, handle->stream);
537     } else {
538         actualBytes = fread(ptr, sizeof(char), desiredBytes, handle->stream);
539     }
540     size_t actualFrames = actualBytes / handle->bytesPerFrame;
541     handle->remaining -= actualFrames;
542     switch (format) {
543     case SF_FORMAT_PCM_U8:
544         memcpy_to_i32_from_u8(ptr, (const unsigned char *) temp,
545                 actualFrames * handle->info.channels);
546         free(temp);
547         break;
548     case SF_FORMAT_PCM_16:
549         memcpy_to_i32_from_i16(ptr, (const short *) temp, actualFrames * handle->info.channels);
550         free(temp);
551         break;
552     case SF_FORMAT_PCM_32:
553         break;
554     case SF_FORMAT_FLOAT:
555         memcpy_to_i32_from_float(ptr, (const float *) ptr, actualFrames * handle->info.channels);
556         break;
557     case SF_FORMAT_PCM_24:
558         memcpy_to_i32_from_p24(ptr, (const uint8_t *) temp, actualFrames * handle->info.channels);
559         free(temp);
560         break;
561     default:
562         memset(ptr, 0, actualFrames * handle->info.channels * sizeof(int));
563         break;
564     }
565     return actualFrames;
566 }
567 
sf_writef_short(SNDFILE * handle,const short * ptr,sf_count_t desiredFrames)568 sf_count_t sf_writef_short(SNDFILE *handle, const short *ptr, sf_count_t desiredFrames)
569 {
570     if (handle == NULL || handle->mode != SFM_WRITE || ptr == NULL || desiredFrames <= 0)
571         return 0;
572     size_t desiredBytes = desiredFrames * handle->bytesPerFrame;
573     size_t actualBytes = 0;
574     switch (handle->info.format & SF_FORMAT_SUBMASK) {
575     case SF_FORMAT_PCM_U8:
576         handle->temp = realloc(handle->temp, desiredBytes);
577         memcpy_to_u8_from_i16(handle->temp, ptr, desiredBytes);
578         actualBytes = fwrite(handle->temp, sizeof(char), desiredBytes, handle->stream);
579         break;
580     case SF_FORMAT_PCM_16:
581         // does not check for numeric overflow
582         if (isLittleEndian()) {
583             actualBytes = fwrite(ptr, sizeof(char), desiredBytes, handle->stream);
584         } else {
585             handle->temp = realloc(handle->temp, desiredBytes);
586             memcpy(handle->temp, ptr, desiredBytes);
587             my_swab((short *) handle->temp, desiredFrames * handle->info.channels);
588             actualBytes = fwrite(handle->temp, sizeof(char), desiredBytes, handle->stream);
589         }
590         break;
591     case SF_FORMAT_FLOAT:
592         handle->temp = realloc(handle->temp, desiredBytes);
593         memcpy_to_float_from_i16((float *) handle->temp, ptr,
594                 desiredFrames * handle->info.channels);
595         actualBytes = fwrite(handle->temp, sizeof(char), desiredBytes, handle->stream);
596         break;
597     default:
598         break;
599     }
600     size_t actualFrames = actualBytes / handle->bytesPerFrame;
601     handle->remaining += actualFrames;
602     return actualFrames;
603 }
604 
sf_writef_float(SNDFILE * handle,const float * ptr,sf_count_t desiredFrames)605 sf_count_t sf_writef_float(SNDFILE *handle, const float *ptr, sf_count_t desiredFrames)
606 {
607     if (handle == NULL || handle->mode != SFM_WRITE || ptr == NULL || desiredFrames <= 0)
608         return 0;
609     size_t desiredBytes = desiredFrames * handle->bytesPerFrame;
610     size_t actualBytes = 0;
611     switch (handle->info.format & SF_FORMAT_SUBMASK) {
612     case SF_FORMAT_FLOAT:
613         actualBytes = fwrite(ptr, sizeof(char), desiredBytes, handle->stream);
614         break;
615     case SF_FORMAT_PCM_16:
616         handle->temp = realloc(handle->temp, desiredBytes);
617         memcpy_to_i16_from_float((short *) handle->temp, ptr,
618                 desiredFrames * handle->info.channels);
619         actualBytes = fwrite(handle->temp, sizeof(char), desiredBytes, handle->stream);
620         break;
621     case SF_FORMAT_PCM_U8:  // transcoding from float to byte not yet implemented
622     default:
623         break;
624     }
625     size_t actualFrames = actualBytes / handle->bytesPerFrame;
626     handle->remaining += actualFrames;
627     return actualFrames;
628 }
629 
sf_writef_int(SNDFILE * handle,const int * ptr,sf_count_t desiredFrames)630 sf_count_t sf_writef_int(SNDFILE *handle, const int *ptr, sf_count_t desiredFrames)
631 {
632     if (handle == NULL || handle->mode != SFM_WRITE || ptr == NULL || desiredFrames <= 0)
633         return 0;
634     size_t desiredBytes = desiredFrames * handle->bytesPerFrame;
635     size_t actualBytes = 0;
636     switch (handle->info.format & SF_FORMAT_SUBMASK) {
637     case SF_FORMAT_PCM_32:
638         actualBytes = fwrite(ptr, sizeof(char), desiredBytes, handle->stream);
639         break;
640     default:    // transcoding from other formats not yet implemented
641         break;
642     }
643     size_t actualFrames = actualBytes / handle->bytesPerFrame;
644     handle->remaining += actualFrames;
645     return actualFrames;
646 }
647