Add missing regex include to generated command_list files.
[paraslash.git] / fecdec_filter.c
1 /*
2 * Copyright (C) 2009 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file fecdec_filter.c A filter fec-decodes an audio stream. */
8
9 #include <regex.h>
10
11 #include <dirent.h>
12 #include "para.h"
13 #include "error.h"
14 #include "list.h"
15 #include "sched.h"
16 #include "ggo.h"
17 #include "filter.h"
18 #include "string.h"
19 #include "portable_io.h"
20 #include "fec.h"
21 #include "fd.h"
22
23 /**
24 * How many FEC groups to store in memory.
25 *
26 * Packet reordering requires to keep more than one FEC group in memory because
27 * slices belonging to the next FEC group may arrive before the current FEC group
28 * is complete.
29 */
30 #define NUM_FEC_GROUPS 3
31
32 /** Default size of the output buffer of the fecdec filter. */
33 #define FECDEC_DEFAULT_OUTBUF_SIZE (3 * 1024)
34 /** Maximal size of the output buffer of the fecdec filter. */
35 #define FECDEC_MAX_OUTBUF_SIZE (1024 * 1024)
36
37 /** Data read from the header of a slice. */
38 struct fec_header {
39 /** Total number of slices in this group. */
40 uint8_t slices_per_group;
41 /** Number of slices needed to start decoding. */
42 uint8_t data_slices_per_group;
43 /** Size of the ogg vorbis header (zero for mp3, aac). */
44 uint32_t audio_header_size;
45 /** Number of the FEC group this slice belongs to. */
46 uint32_t group_num;
47 /** Size of the data in this FEC group. */
48 uint32_t group_bytes;
49 /** Number of this slice in the group. */
50 uint8_t slice_num;
51 /** Used data bytes of this slice. */
52 uint16_t slice_bytes;
53 /** Non-zero if this group is the beginning of the stream. */
54 uint8_t bos;
55 /** Non-zero if this stream embedds audio headers into fec groups. */
56 uint8_t header_stream;
57 };
58
59 /**
60 * The status of one partially received FEC group.
61 */
62 struct fecdec_group {
63 /** The header read from the last slice. */
64 struct fec_header h;
65 /** How many slices received so far. */
66 int num_received_slices;
67 /** The size of the \a idx and the \a data arrays below. */
68 int num_slices;
69 /** Array of indices of the received slices. */
70 int *idx;
71 /** Content of the received slices. */
72 unsigned char **data;
73 };
74
75 /**
76 * Data private to the fecdec filter.
77 */
78 struct private_fecdec_data {
79 /** Used by the fec core code. */
80 struct fec_parms *fec;
81 /** Keeps track of what was received so far. */
82 struct fecdec_group groups[NUM_FEC_GROUPS];
83 /** Whether an audio file header was already received. */
84 int have_header;
85 };
86
87 /** Iterate over all fecdec groups. */
88 #define FOR_EACH_FECDEC_GROUP(g, d) for (g = (d)->groups; \
89 (g) - (d)->groups < NUM_FEC_GROUPS; (g)++)
90
91 static int group_complete(struct fecdec_group *fg)
92 {
93 return fg->num_received_slices >= fg->h.data_slices_per_group;
94 }
95
96 static int group_empty(struct fecdec_group *fg)
97 {
98 return fg->num_received_slices == 0;
99 }
100
101 static void clear_group(struct fecdec_group *fg)
102 {
103 int i;
104
105 for (i = 0; i < fg->num_slices; i++) {
106 free(fg->data[i]);
107 fg->data[i] = NULL;
108 fg->idx[i] = -1;
109 }
110 free(fg->data);
111 free(fg->idx);
112 fg->num_slices = 0;
113 memset(&fg->h, 0, sizeof(struct fec_header));
114 fg->num_received_slices = 0;
115 }
116
117 static int find_group(struct fec_header *h,
118 struct private_fecdec_data *pfd, struct fecdec_group **result)
119 {
120 struct fecdec_group *fg;
121
122 FOR_EACH_FECDEC_GROUP(fg, pfd) {
123 if (fg->h.group_num != h->group_num)
124 continue;
125 if (fg->num_received_slices == 0)
126 goto success;
127 if (fg->h.slices_per_group != h->slices_per_group)
128 return -E_BAD_FEC_HEADER;
129 if (fg->h.data_slices_per_group != h->data_slices_per_group)
130 return -E_BAD_FEC_HEADER;
131 if (fg->h.group_bytes != h->group_bytes)
132 return -E_BAD_FEC_HEADER;
133 success:
134 *result = fg;
135 return 1;
136 }
137 return 0;
138 }
139
140 static struct fecdec_group *find_unused_group(struct private_fecdec_data *pfd)
141 {
142 struct fecdec_group *fg;
143
144 FOR_EACH_FECDEC_GROUP(fg, pfd) {
145 if (fg->num_received_slices == 0)
146 return fg;
147 }
148 return NULL;
149 }
150
151 static struct fecdec_group *try_to_free_group(struct private_fecdec_data *pfd)
152 {
153 struct fecdec_group *fg;
154
155 FOR_EACH_FECDEC_GROUP(fg, pfd) {
156 if (!group_complete(fg))
157 continue;
158 clear_group(fg);
159 return fg;
160 }
161 return NULL;
162 }
163
164 static struct fecdec_group *free_oldest_group(struct private_fecdec_data *pfd)
165 {
166 struct fecdec_group *fg, *oldest = NULL;
167
168 FOR_EACH_FECDEC_GROUP(fg, pfd) {
169 if (!oldest || oldest->h.group_num > fg->h.group_num)
170 oldest = fg;
171 }
172 if (!group_complete(oldest) && !group_empty(oldest))
173 PARA_WARNING_LOG("Clearing incomplete group %d "
174 "(contains %d slices)\n", oldest->h.group_num,
175 oldest->num_received_slices);
176 clear_group(oldest);
177 return oldest;
178 }
179
180 /* returns 1 if the group was found, 0 if not, negative on errors */
181 static int get_group(struct fec_header *h, struct private_fecdec_data *pfd,
182 struct fecdec_group **result)
183 {
184 struct fecdec_group *fg;
185 int ret = find_group(h, pfd, &fg);
186
187 if (ret < 0)
188 return ret;
189 if (ret > 0) /* found group */
190 goto success;
191 /* group not found */
192 fg = find_unused_group(pfd);
193 if (fg)
194 goto success;
195 fg = try_to_free_group(pfd);
196 if (fg)
197 goto success;
198 fg = free_oldest_group(pfd);
199 ret = 0;
200 success:
201 fg->h = *h;
202 *result = fg;
203 return ret;
204 }
205
206 /*
207 * returns 1 if slice was added, zero otherwise (because the group was already
208 * complete). In any case the number of received slices is being increased by
209 * one.
210 */
211 static int add_slice(char *buf, struct fecdec_group *fg)
212 {
213 int r, slice_num;
214
215 if (group_complete(fg)) {
216 PARA_DEBUG_LOG("group complete, ignoring slice %d\n",
217 fg->h.slice_num);
218 fg->num_received_slices++;
219 return 0;
220 }
221 slice_num = fg->h.slice_num;
222 if (fg->num_slices == 0) {
223 fg->num_slices = fg->h.slices_per_group;
224 fg->idx = malloc(fg->num_slices * sizeof(int));
225 fg->data = malloc(fg->num_slices * sizeof(unsigned char *));
226 memset(fg->data, 0, fg->num_slices * sizeof(unsigned char *));
227 }
228 r = fg->num_received_slices;
229 fg->idx[r] = slice_num;
230 fg->data[r] = malloc(fg->h.slice_bytes);
231 memcpy(fg->data[r], buf, fg->h.slice_bytes);
232 fg->num_received_slices++;
233 return 1;
234 }
235
236 enum fec_group_usability {
237 FEC_GROUP_UNUSABLE,
238 FEC_GROUP_USABLE,
239 FEC_GROUP_USABLE_SKIP_HEADER,
240 };
241
242 static enum fec_group_usability group_is_usable(struct fecdec_group *fg,
243 struct private_fecdec_data *pfd)
244 {
245 struct fec_header *h = &fg->h;
246
247 if (!h->header_stream)
248 return FEC_GROUP_USABLE;
249 if (pfd->have_header) {
250 if (h->audio_header_size)
251 return FEC_GROUP_USABLE_SKIP_HEADER;
252 return FEC_GROUP_USABLE;
253 }
254 if (fg->h.bos)
255 return FEC_GROUP_USABLE;
256 if (fg->h.audio_header_size)
257 return FEC_GROUP_USABLE;
258 return FEC_GROUP_UNUSABLE;
259 }
260
261 static int decode_group(struct fecdec_group *fg, struct filter_node *fn)
262 {
263 int i, ret, sb = fg->h.slice_bytes;
264 size_t written = 0, need;
265 struct private_fecdec_data *pfd = fn->private_data;
266 enum fec_group_usability u = group_is_usable(fg, pfd);
267
268 if (u == FEC_GROUP_UNUSABLE) {
269 PARA_INFO_LOG("dropping unusable group %d\n", fg->h.group_num);
270 return 0;
271 }
272 PARA_DEBUG_LOG("decoding group %d %d slices\n", fg->h.group_num,
273 fg->h.data_slices_per_group);
274 ret = fec_decode(pfd->fec, fg->data, fg->idx, sb);
275 if (ret < 0)
276 return ret;
277 pfd->have_header = 1;
278 i = 0;
279 if (u == FEC_GROUP_USABLE_SKIP_HEADER) {
280 i = ROUND_UP(fg->h.audio_header_size, fg->h.slice_bytes)
281 / fg->h.slice_bytes;
282 PARA_DEBUG_LOG("skipping %d header slices\n", i);
283 }
284 PARA_DEBUG_LOG("writing group %d (%d/%d decoded data bytes)\n",
285 fg->h.group_num, fg->h.group_bytes,
286 fg->h.data_slices_per_group * sb);
287 need = fn->loaded + (fg->h.data_slices_per_group - i)* sb;
288 if (need > fn->bufsize) {
289 fn->bufsize = PARA_MAX(fn->bufsize * 2, need);
290 if (fn->bufsize > FECDEC_MAX_OUTBUF_SIZE)
291 return -E_FECDEC_OVERRUN;
292 PARA_INFO_LOG("increasing fec buf to %zu\n", fn->bufsize);
293 fn->buf = para_realloc(fn->buf, fn->bufsize);
294 }
295 for (; i < fg->h.data_slices_per_group; i++) {
296 size_t n = sb;
297 if (n + written > fg->h.group_bytes)
298 n = fg->h.group_bytes - written;
299 memcpy(fn->buf + fn->loaded, fg->data[i], n);
300 fn->loaded += n;
301 written += n;
302 }
303 return 0;
304 }
305
306 /**
307 * Read a fec header from a buffer.
308 *
309 * \param buf The buffer to write to.
310 * \param h The fec header to write.
311 */
312 static int read_fec_header(char *buf, size_t len, struct fec_header *h)
313 {
314 uint32_t magic;
315
316 if (len < FEC_HEADER_SIZE)
317 return 0;
318 magic = read_u32(buf);
319 if (magic != FEC_MAGIC)
320 return -E_BAD_FEC_HEADER;
321 h->slices_per_group = read_u8(buf + 4);
322 h->data_slices_per_group = read_u8(buf + 5);
323 h->audio_header_size = read_u32(buf + 6);
324
325 h->group_num = read_u32(buf + 10);
326 h->group_bytes = read_u32(buf + 14);
327
328 h->slice_num = read_u8(buf + 18);
329 h->slice_bytes = read_u16(buf + 20);
330 h->bos = read_u8(buf + 22);
331 h->header_stream = read_u8(buf + 23);
332 if (!memcmp(buf, FEC_EOF_PACKET, FEC_EOF_PACKET_LEN))
333 return -E_FECDEC_EOF;
334 // PARA_DEBUG_LOG("group %u, slize %u, slices per group: %u\n",
335 // h->group_num, h->slice_num, h->slices_per_group);
336 return 1;
337 }
338
339 /* returns 1 if we used the buffer, 0 if we didn't, negative on errors */
340 static int dispatch_slice(char *buf, size_t len, struct fec_header *h,
341 struct filter_node *fn)
342 {
343 struct fecdec_group *fg;
344 int ret;
345 struct private_fecdec_data *pfd = fn->private_data;
346
347 if (h->slice_bytes > len) /* can not use the thing, try to read more */
348 return 0;
349 ret = get_group(h, pfd, &fg);
350 if (ret < 0)
351 return ret;
352 if (!add_slice(buf, fg))
353 return 1;
354 if (group_complete(fg)) {
355 if (!pfd->fec) {
356 int k = h->data_slices_per_group, n = h->slices_per_group;
357 PARA_NOTICE_LOG("init fec (%d, %d)\n", k, n);
358 ret = fec_new(k, n, &pfd->fec);
359 if (ret < 0)
360 return ret;
361 }
362 ret = decode_group(fg, fn);
363 if (ret < 0)
364 return ret;
365 }
366 return 1;
367 }
368
369 static ssize_t fecdec(char *buf, size_t len, struct filter_node *fn)
370 {
371 int ret;
372 struct fec_header h;
373
374 ret = read_fec_header(buf, len, &h);
375 if (ret <= 0)
376 return ret;
377 if (!h.slice_bytes)
378 return -E_BAD_SLICE_SIZE;
379 if (h.slice_num > h.slices_per_group)
380 return -E_BAD_SLICE_NUM;
381 ret = dispatch_slice(buf + FEC_HEADER_SIZE, len - FEC_HEADER_SIZE,
382 &h, fn);
383 //PARA_INFO_LOG("ret: %d, len: %d, slice_bytes: %d\n", ret, len, h.slice_bytes);
384 if (ret <= 0)
385 return ret;
386 return FEC_HEADER_SIZE + h.slice_bytes;
387 }
388
389 static void fecdec_close(struct filter_node *fn)
390 {
391 struct private_fecdec_data *pfd = fn->private_data;
392 struct fecdec_group *fg;
393
394 FOR_EACH_FECDEC_GROUP(fg, pfd)
395 clear_group(fg);
396 free(fn->buf);
397 fn->buf = NULL;
398 fec_free(pfd->fec);
399 free(fn->private_data);
400 fn->private_data = NULL;
401 }
402
403 static void fecdec_open(struct filter_node *fn)
404 {
405 fn->bufsize = FECDEC_DEFAULT_OUTBUF_SIZE;
406 fn->buf = para_malloc(fn->bufsize);
407 fn->private_data = para_calloc(sizeof(struct private_fecdec_data));
408 fn->loaded = 0;
409 }
410
411 /**
412 * The init function of the fecdec filter.
413 *
414 * \param f struct to initialize.
415 */
416 void fecdec_filter_init(struct filter *f)
417 {
418 f->convert = fecdec;
419 f->close = fecdec_close;
420 f->open = fecdec_open;
421 }