src/memblockq.c

   1 #include <sys/time.h>
   2 #include <time.h>
   3 #include <stdio.h>
   4 #include <assert.h>
   5 #include <stdlib.h>
   6
   7 #include "memblockq.h"
   8
   9 struct memblock_list {
  10     struct memblock_list *next;
  11     struct pa_memchunk chunk;
  12     struct timeval stamp;
  13 };
  14
  15 struct pa_memblockq {
  16     struct memblock_list *blocks, *blocks_tail;
  17     unsigned n_blocks;
  18     size_t current_length, maxlength, tlength, base, prebuf, minreq;
  19     int measure_delay;
  20     uint32_t delay;
  21     struct pa_mcalign *mcalign;
  22 };
  23
  24 struct pa_memblockq* pa_memblockq_new(size_t maxlength, size_t tlength, size_t base, size_t prebuf, size_t minreq) {
  25     struct pa_memblockq* bq;
  26     assert(maxlength && base && maxlength);
  27
  28     bq = malloc(sizeof(struct pa_memblockq));
  29     assert(bq);
  30     bq->blocks = bq->blocks_tail = 0;
  31     bq->n_blocks = 0;
  32
  33     bq->current_length = 0;
  34
  35     fprintf(stderr, "memblockq requested: maxlength=%u, tlength=%u, base=%u, prebuf=%u, minreq=%u\n", maxlength, tlength, base, prebuf, minreq);
  36
  37     bq->base = base;
  38
  39     bq->maxlength = ((maxlength+base-1)/base)*base;
  40     assert(bq->maxlength >= base);
  41
  42     bq->tlength = ((tlength+base-1)/base)*base;
  43     if (bq->tlength == 0 || bq->tlength >= bq->maxlength)
  44         bq->tlength = bq->maxlength;
  45
  46     bq->prebuf = (prebuf == (size_t) -1) ? bq->maxlength/2 : prebuf;
  47     bq->prebuf = (bq->prebuf/base)*base;
  48     if (bq->prebuf > bq->maxlength)
  49         bq->prebuf = bq->maxlength;
  50
  51     bq->minreq = (minreq/base)*base;
  52     if (bq->minreq == 0)
  53         bq->minreq = 1;
  54
  55     fprintf(stderr, "memblockq sanitized: maxlength=%u, tlength=%u, base=%u, prebuf=%u, minreq=%u\n", bq->maxlength, bq->tlength, bq->base, bq->prebuf, bq->minreq);
  56
  57     bq->measure_delay = 0;
  58     bq->delay = 0;
  59
  60     bq->mcalign = NULL;
  61
  62     return bq;
  63 }
  64
  65 void pa_memblockq_free(struct pa_memblockq* bq) {
  66     struct memblock_list *l;
  67     assert(bq);
  68
  69     if (bq->mcalign)
  70         pa_mcalign_free(bq->mcalign);
  71
  72     while ((l = bq->blocks)) {
  73         bq->blocks = l->next;
  74         pa_memblock_unref(l->chunk.memblock);
  75         free(l);
  76     }
  77
  78     free(bq);
  79 }
  80
  81 void pa_memblockq_push(struct pa_memblockq* bq, const struct pa_memchunk *chunk, size_t delta) {
  82     struct memblock_list *q;
  83     assert(bq && chunk && chunk->memblock && chunk->length && (chunk->length % bq->base) == 0);
  84
  85     q = malloc(sizeof(struct memblock_list));
  86     assert(q);
  87
  88     if (bq->measure_delay)
  89         gettimeofday(&q->stamp, NULL);
  90     else
  91         timerclear(&q->stamp);
  92
  93     q->chunk = *chunk;
  94     pa_memblock_ref(q->chunk.memblock);
  95     assert(q->chunk.index+q->chunk.length <= q->chunk.memblock->length);
  96     q->next = NULL;
  97
  98     if (bq->blocks_tail)
  99         bq->blocks_tail->next = q;
 100     else
 101         bq->blocks = q;
 102
 103     bq->blocks_tail = q;
 104
 105     bq->n_blocks++;
 106     bq->current_length += chunk->length;
 107
 108     pa_memblockq_shorten(bq, bq->maxlength);
 109 }
 110
 111 int pa_memblockq_peek(struct pa_memblockq* bq, struct pa_memchunk *chunk) {
 112     assert(bq && chunk);
 113
 114     if (!bq->blocks || bq->current_length < bq->prebuf)
 115         return -1;
 116
 117     bq->prebuf = 0;
 118
 119     *chunk = bq->blocks->chunk;
 120     pa_memblock_ref(chunk->memblock);
 121
 122 /*     if (chunk->memblock->ref != 2) */
 123 /*         fprintf(stderr, "block %p with ref %u peeked.\n", chunk->memblock, chunk->memblock->ref); */
 124
 125     return 0;
 126 }
 127
 128 /*
 129 int memblockq_pop(struct memblockq* bq, struct pa_memchunk *chunk) {
 130     struct memblock_list *q;
 131
 132     assert(bq && chunk);
 133
 134     if (!bq->blocks || bq->current_length < bq->prebuf)
 135         return -1;
 136
 137     bq->prebuf = 0;
 138
 139     q = bq->blocks;
 140     bq->blocks = bq->blocks->next;
 141
 142     *chunk = q->chunk;
 143
 144     bq->n_blocks--;
 145     bq->current_length -= chunk->length;
 146
 147     free(q);
 148     return 0;
 149 }
 150 */
 151
 152 static uint32_t age(struct timeval *tv) {
 153     assert(tv);
 154     struct timeval now;
 155     uint32_t r;
 156
 157     if (tv->tv_sec == 0)
 158         return 0;
 159
 160     gettimeofday(&now, NULL);
 161
 162     r = (now.tv_sec-tv->tv_sec) * 1000000;
 163
 164     if (now.tv_usec >= tv->tv_usec)
 165         r += now.tv_usec - tv->tv_usec;
 166     else
 167         r -= tv->tv_usec - now.tv_usec;
 168
 169     return r;
 170 }
 171
 172 void pa_memblockq_drop(struct pa_memblockq *bq, size_t length) {
 173     assert(bq && length && (length % bq->base) == 0);
 174
 175     while (length > 0) {
 176         size_t l = length;
 177         assert(bq->blocks && bq->current_length >= length);
 178
 179         if (l > bq->blocks->chunk.length)
 180             l = bq->blocks->chunk.length;
 181
 182         if (bq->measure_delay)
 183             bq->delay = age(&bq->blocks->stamp);
 184
 185         bq->blocks->chunk.index += l;
 186         bq->blocks->chunk.length -= l;
 187         bq->current_length -= l;
 188
 189         if (bq->blocks->chunk.length == 0) {
 190             struct memblock_list *q;
 191
 192             q = bq->blocks;
 193             bq->blocks = bq->blocks->next;
 194             if (bq->blocks == NULL)
 195                 bq->blocks_tail = NULL;
 196             pa_memblock_unref(q->chunk.memblock);
 197             free(q);
 198
 199             bq->n_blocks--;
 200         }
 201
 202         length -= l;
 203     }
 204 }
 205
 206 void pa_memblockq_shorten(struct pa_memblockq *bq, size_t length) {
 207     size_t l;
 208     assert(bq);
 209
 210     if (bq->current_length <= length)
 211         return;
 212
 213     fprintf(stderr, "Warning! pa_memblockq_shorten()\n");
 214
 215     l = bq->current_length - length;
 216     l /= bq->base;
 217     l *= bq->base;
 218
 219     pa_memblockq_drop(bq, l);
 220 }
 221
 222
 223 void pa_memblockq_empty(struct pa_memblockq *bq) {
 224     assert(bq);
 225     pa_memblockq_shorten(bq, 0);
 226 }
 227
 228 int pa_memblockq_is_readable(struct pa_memblockq *bq) {
 229     assert(bq);
 230
 231     return bq->current_length && (bq->current_length >= bq->prebuf);
 232 }
 233
 234 int pa_memblockq_is_writable(struct pa_memblockq *bq, size_t length) {
 235     assert(bq);
 236
 237     return bq->current_length + length <= bq->tlength;
 238 }
 239
 240 uint32_t pa_memblockq_get_delay(struct pa_memblockq *bq) {
 241     assert(bq);
 242     return bq->delay;
 243 }
 244
 245 uint32_t pa_memblockq_get_length(struct pa_memblockq *bq) {
 246     assert(bq);
 247     return bq->current_length;
 248 }
 249
 250 uint32_t pa_memblockq_missing(struct pa_memblockq *bq) {
 251     size_t l;
 252     assert(bq);
 253
 254     if (bq->current_length >= bq->tlength)
 255         return 0;
 256
 257     l = bq->tlength - bq->current_length;
 258     assert(l);
 259
 260     return (l >= bq->minreq) ? l : 0;
 261 }
 262
 263 void pa_memblockq_push_align(struct pa_memblockq* bq, const struct pa_memchunk *chunk, size_t delta) {
 264     struct pa_memchunk rchunk;
 265     assert(bq && chunk && bq->base);
 266
 267     if (bq->base == 1) {
 268         pa_memblockq_push(bq, chunk, delta);
 269         return;
 270     }
 271
 272     if (!bq->mcalign) {
 273         bq->mcalign = pa_mcalign_new(bq->base);
 274         assert(bq->mcalign);
 275     }
 276
 277     pa_mcalign_push(bq->mcalign, chunk);
 278
 279     while (pa_mcalign_pop(bq->mcalign, &rchunk) >= 0) {
 280         pa_memblockq_push(bq, &rchunk, delta);
 281         pa_memblock_unref(rchunk.memblock);
 282         delta = 0;
 283     }
 284 }
 285
 286 uint32_t pa_memblockq_get_minreq(struct pa_memblockq *bq) {
 287     assert(bq);
 288     return bq->minreq;
 289 }