crypt_common.c: Add missing doxygen documentation.
[paraslash.git] / fecdec_filter.c
index 08a0ad0..fb2dba0 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2009-2011 Andre Noll <maan@systemlinux.org>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -7,13 +7,14 @@
 /** \file fecdec_filter.c A filter that fec-decodes an audio stream. */
 
 #include <regex.h>
+#include <stdbool.h>
 
-#include <dirent.h>
 #include "para.h"
 #include "error.h"
 #include "list.h"
 #include "sched.h"
 #include "ggo.h"
+#include "buffer_tree.h"
 #include "filter.h"
 #include "string.h"
 #include "portable_io.h"
  */
 #define NUM_FEC_GROUPS 3
 
-/** Default size of the output buffer of the fecdec filter. */
-#define FECDEC_DEFAULT_OUTBUF_SIZE (3 * 1024)
-/** Maximal size of the output buffer of the fecdec filter. */
-#define FECDEC_MAX_OUTBUF_SIZE (1024 * 1024)
-
 /** Data read from the header of a slice. */
 struct fec_header {
        /** Total number of slices in this group. */
        uint8_t slices_per_group;
        /** Number of slices needed to start decoding. */
        uint8_t data_slices_per_group;
-       /** Size of the ogg vorbis header (zero for mp3, aac). */
+       /** Size of the ogg vorbis/wma header (zero for mp3, aac). */
        uint32_t audio_header_size;
        /** Number of the FEC group this slice belongs to. */
        uint32_t group_num;
@@ -64,6 +60,8 @@ struct fecdec_group {
        struct fec_header h;
        /** How many slices received so far. */
        int num_received_slices;
+       /** Bitmap of received slices. */
+       uint8_t received_slices[32];
        /** The size of the \a idx and the \a data arrays below. */
        int num_slices;
        /** Array of indices of the received slices. */
@@ -84,6 +82,7 @@ struct private_fecdec_data {
        int have_header;
        /** Points to the first received group. */
        struct fecdec_group *first_complete_group;
+       struct btr_pool *btrp;
 };
 
 /** Iterate over all fecdec groups. */
@@ -104,16 +103,11 @@ static void clear_group(struct fecdec_group *fg)
 {
        int i;
 
-       for (i = 0; i < fg->num_slices; i++) {
+       for (i = 0; i < fg->num_slices; i++)
                free(fg->data[i]);
-               fg->data[i] = NULL;
-               fg->idx[i] = -1;
-       }
        free(fg->data);
        free(fg->idx);
-       fg->num_slices = 0;
-       memset(&fg->h, 0, sizeof(struct fec_header));
-       fg->num_received_slices = 0;
+       memset(fg, 0, sizeof(*fg));
 }
 
 static int find_group(struct fec_header *h,
@@ -213,29 +207,40 @@ success:
        return ret;
 }
 
+static bool test_and_set_slice_bit(struct fecdec_group *fg, uint8_t slice_num)
+{
+       uint8_t *p = fg->received_slices + slice_num / 8, old = *p;
+
+       *p |= 1 << (slice_num % 8);
+       return old == *p;
+}
+
 /*
  * returns 1 if slice was added, zero otherwise (because the group was already
- * complete). In any case the number of received slices is being increased by
- * one.
+ * complete or a slice has been received twice).
  */
 static int add_slice(char *buf, struct fecdec_group *fg)
 {
-       int r, slice_num;
+       int r;
+       uint8_t slice_num = fg->h.slice_num;
 
        if (group_complete(fg)) {
                PARA_DEBUG_LOG("group %d complete, ignoring slice %d\n",
-                       fg->h.group_num, fg->h.slice_num);
-               fg->num_received_slices++;
+                       fg->h.group_num, slice_num);
                return 0;
        }
-       slice_num = fg->h.slice_num;
        if (fg->num_slices == 0) {
                fg->num_slices = fg->h.slices_per_group;
                fg->idx = para_malloc(fg->num_slices * sizeof(int));
-               fg->data = para_malloc(fg->num_slices * sizeof(unsigned char *));
-               memset(fg->data, 0, fg->num_slices * sizeof(unsigned char *));
+               fg->data = para_calloc(fg->num_slices * sizeof(unsigned char *));
        }
        r = fg->num_received_slices;
+       /* Check if we already have this slice. */
+       if (test_and_set_slice_bit(fg, slice_num)) {
+               PARA_INFO_LOG("ignoring duplicate slice %d:%d\n", fg->h.group_num,
+                       slice_num);
+               return 0;
+       }
        fg->idx[r] = slice_num;
        fg->data[r] = para_malloc(fg->h.slice_bytes);
        memcpy(fg->data[r], buf, fg->h.slice_bytes);
@@ -243,10 +248,21 @@ static int add_slice(char *buf, struct fecdec_group *fg)
        return 1;
 }
 
+/**
+ * The different states of a complete FEC group.
+ *
+ * Even if a FEC group has been received successfully, it probably can not be
+ * used right away because some streams (ogg, wma) need to receive an audio
+ * file header before decoding can start.
+ */
 enum fec_group_usability {
+       /** Drop the group (because we did not receive the header yet). */
        FEC_GROUP_UNUSABLE,
+       /** Use all data in the group. */
        FEC_GROUP_USABLE,
+       /** Use the group, but drop its audio file header. */
        FEC_GROUP_USABLE_SKIP_HEADER,
+       /** Use the group, including its header. */
        FEC_GROUP_USABLE_WITH_HEADER
 };
 
@@ -275,6 +291,7 @@ static int decode_group(struct fecdec_group *fg, struct filter_node *fn)
        size_t written, need;
        struct private_fecdec_data *pfd = fn->private_data;
        enum fec_group_usability u = group_is_usable(fg, pfd);
+       char *buf = NULL, *p;
 
        if (u == FEC_GROUP_UNUSABLE) {
                PARA_INFO_LOG("dropping unusable group %d\n", fg->h.group_num);
@@ -288,21 +305,17 @@ static int decode_group(struct fecdec_group *fg, struct filter_node *fn)
        pfd->have_header = 1;
        i = 0;
        if (u == FEC_GROUP_USABLE_SKIP_HEADER) {
-               i = ROUND_UP(fg->h.audio_header_size, fg->h.slice_bytes)
-                       / fg->h.slice_bytes;
+               i = DIV_ROUND_UP(fg->h.audio_header_size, fg->h.slice_bytes);
                PARA_DEBUG_LOG("skipping %d header slices\n", i);
        }
        PARA_DEBUG_LOG("writing group %d (%d/%d decoded data bytes)\n",
                fg->h.group_num, fg->h.group_bytes,
                fg->h.data_slices_per_group * sb);
-       need = fn->loaded + (fg->h.data_slices_per_group - i)* sb;
-       if (need > fn->bufsize) {
-               fn->bufsize = PARA_MAX(fn->bufsize * 2, need);
-               if (fn->bufsize > FECDEC_MAX_OUTBUF_SIZE)
-                       return -E_FECDEC_OVERRUN;
-               PARA_INFO_LOG("increasing fec buf to %zu\n", fn->bufsize);
-               fn->buf = para_realloc(fn->buf, fn->bufsize);
-       }
+       need = (fg->h.data_slices_per_group - i) * sb;
+       if (need > btr_pool_unused(pfd->btrp))
+               return -E_FECDEC_OVERRUN;
+       btr_pool_get_buffer(pfd->btrp, &buf);
+       p = buf;
        if (u == FEC_GROUP_USABLE_WITH_HEADER) {
                PARA_INFO_LOG("writing audio file header\n");
                written = 0;
@@ -312,20 +325,20 @@ static int decode_group(struct fecdec_group *fg, struct filter_node *fn)
                                break;
                        if (sb + written > fg->h.audio_header_size)
                                n = fg->h.audio_header_size - written;
-                       memcpy(fn->buf + fn->loaded, fg->data[i], n);
-                       fn->loaded += n;
+                       btr_copy(fg->data[i], n, pfd->btrp, fn->btrn);
                        written += n;
                }
+               p += written;
        }
        written = 0;
        for (; i < fg->h.data_slices_per_group; i++) {
                size_t n = sb;
                if (n + written > fg->h.group_bytes)
                        n = fg->h.group_bytes - written;
-               memcpy(fn->buf + fn->loaded, fg->data[i], n);
-               fn->loaded += n;
+               btr_copy(fg->data[i], n, pfd->btrp, fn->btrn);
                written += n;
        }
+       p += written;
        return 0;
 }
 
@@ -370,8 +383,10 @@ static int dispatch_slice(char *buf, size_t len, struct fec_header *h,
        int ret, k, n;
        struct private_fecdec_data *pfd = fn->private_data;
 
-       if (h->slice_bytes > len) /* can not use the thing, try to read more */
+       if (h->slice_bytes > len) { /* can not use the thing, try to read more */
+               fn->min_iqs = h->slice_bytes + FEC_HEADER_SIZE;
                return 0;
+       }
        ret = get_group(h, pfd, &fg);
        if (ret < 0)
                return ret;
@@ -398,6 +413,7 @@ static int dispatch_slice(char *buf, size_t len, struct fec_header *h,
        ret = fec_new(k, n, &pfd->fec);
        if (ret < 0)
                return ret;
+       pfd->btrp = btr_pool_new("fecdec", 64 * 1024);
        /* decode and clear the first group */
        ret = decode_group(pfd->first_complete_group, fn);
        if (ret < 0)
@@ -411,58 +427,73 @@ decode:
        return 1;
 }
 
-static ssize_t fecdec(char *buf, size_t len, struct filter_node *fn)
+static void fecdec_close(struct filter_node *fn)
 {
+       struct private_fecdec_data *pfd = fn->private_data;
+       struct fecdec_group *fg;
+
+       FOR_EACH_FECDEC_GROUP(fg, pfd)
+               clear_group(fg);
+       fec_free(pfd->fec);
+       btr_pool_free(pfd->btrp);
+       free(fn->private_data);
+       fn->private_data = NULL;
+}
+
+static void fecdec_post_select(__a_unused struct sched *s, struct task *t)
+{
+       struct filter_node *fn = container_of(t, struct filter_node, task);
+       struct btr_node *btrn = fn->btrn;
        int ret;
        struct fec_header h;
+       char *buf;
+       size_t len;
 
+next_buffer:
+       ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
+       if (ret <= 0)
+               goto out;
+       btr_merge(btrn, fn->min_iqs);
+       len = btr_next_buffer(btrn, &buf);
        ret = read_fec_header(buf, len, &h);
        if (ret <= 0)
-               return ret;
+               goto out;
+       ret = -E_BAD_SLICE_SIZE;
        if (!h.slice_bytes)
-               return -E_BAD_SLICE_SIZE;
+               goto out;
+       ret = -E_BAD_SLICE_NUM;
        if (h.slice_num > h.slices_per_group)
-               return -E_BAD_SLICE_NUM;
+               goto out;
        ret = dispatch_slice(buf + FEC_HEADER_SIZE, len - FEC_HEADER_SIZE,
                &h, fn);
        //PARA_INFO_LOG("ret: %d, len: %d, slice_bytes: %d\n", ret, len, h.slice_bytes);
        if (ret <= 0)
-               return ret;
-       return FEC_HEADER_SIZE + h.slice_bytes;
-}
-
-static void fecdec_close(struct filter_node *fn)
-{
-       struct private_fecdec_data *pfd = fn->private_data;
-       struct fecdec_group *fg;
-
-       FOR_EACH_FECDEC_GROUP(fg, pfd)
-               clear_group(fg);
-       free(fn->buf);
-       fn->buf = NULL;
-       fec_free(pfd->fec);
-       free(fn->private_data);
-       fn->private_data = NULL;
+               goto out;
+       btr_consume(btrn, FEC_HEADER_SIZE + h.slice_bytes);
+       goto next_buffer;
+out:
+       t->error = ret;
+       if (ret < 0)
+               btr_remove_node(btrn);
 }
 
 static void fecdec_open(struct filter_node *fn)
 {
        struct private_fecdec_data *pfd;
-       fn->bufsize = FECDEC_DEFAULT_OUTBUF_SIZE;
-       fn->buf = para_malloc(fn->bufsize);
        pfd = para_calloc(sizeof(*pfd));
        fn->private_data = pfd;
-       fn->loaded = 0;
+       fn->min_iqs = FEC_HEADER_SIZE;
 }
 
 /**
  * The init function of the fecdec filter.
  *
- * \param f struct to initialize.
+ * \param f Struct to initialize.
  */
 void fecdec_filter_init(struct filter *f)
 {
-       f->convert = fecdec;
        f->close = fecdec_close;
        f->open = fecdec_open;
+       f->pre_select = generic_filter_pre_select;
+       f->post_select = fecdec_post_select;
 }