-/*
- * Copyright (C) 2005-2012 Andre Noll <maan@systemlinux.org>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
/** \file check_wav.c Detect and delete a wav header. */
#include "buffer_tree.h"
#include "error.h"
#include "check_wav.h"
+#include "portable_io.h"
/** Length of a standard wav header. */
#define WAV_HEADER_LEN 44
+/** The possible states of a check_wav instance. */
enum check_wav_state {
+ /** Initial state, less than \p WAV_HEADER_LEN bytes available. */
CWS_NEED_HEADER,
+ /** Wav hader was detected. */
CWS_HAVE_HEADER,
+ /** First part of the stream did not look like a wav header. */
CWS_NO_HEADER,
};
-struct check_wav_task {
+struct check_wav_context {
enum check_wav_state state;
- struct task task;
struct btr_node *btrn;
size_t min_iqs;
/* Command line args. */
unsigned sample_rate;
};
-static void check_wav_pre_select(struct sched *s, struct task *t)
+/**
+ * Set select timeout according to the given context.
+ *
+ * \param s Contains the timeval that should be set.
+ * \param cwc Contains a pointer to the buffer tree node.
+ *
+ * This requests a minimal timeout from the scheduler if btrn of \a cwc is not
+ * idle.
+ */
+void check_wav_pre_select(struct sched *s, struct check_wav_context *cwc)
{
- struct check_wav_task *cwt = container_of(t, struct check_wav_task, task);
- int ret;
-
- ret = btr_node_status(cwt->btrn, cwt->min_iqs, BTR_NT_INTERNAL);
+ int ret = btr_node_status(cwc->btrn, cwc->min_iqs, BTR_NT_INTERNAL);
if (ret != 0)
sched_min_delay(s);
}
static int check_wav_exec(struct btr_node *btrn, const char *cmd, char **result)
{
- struct check_wav_task *cwt = btr_context(btrn);
+ struct check_wav_context *cwc = btr_context(btrn);
int val, header_val, given, arg;
- header_val = cwt->channels;
- arg = cwt->params.channels_arg;
- given = cwt->params.channels_given;
+ header_val = cwc->channels;
+ arg = cwc->params.channels_arg;
+ given = cwc->params.channels_given;
if (!strcmp(cmd, "channels"))
goto out;
- header_val = cwt->sample_rate;
- arg = cwt->params.sample_rate_arg;
- given = cwt->params.sample_rate_given;
+ header_val = cwc->sample_rate;
+ arg = cwc->params.sample_rate_arg;
+ given = cwc->params.sample_rate_given;
if (!strcmp(cmd, "sample_rate"))
goto out;
- header_val = cwt->sample_format;
- arg = cwt->params.sample_format_arg;
- given = cwt->params.sample_format_given;
+ header_val = cwc->sample_format;
+ arg = cwc->params.sample_format_arg;
+ given = cwc->params.sample_format_given;
if (!strcmp(cmd, "sample_format"))
goto out;
if (given)
val = arg;
else {
- switch (cwt->state) {
+ switch (cwc->state) {
case CWS_HAVE_HEADER:
val = header_val;
break;
case CWS_NO_HEADER:
+ /*
+ * No wav header available and no value specified at
+ * the command line. Maybe one of our parent nodes
+ * knows.
+ */
+ if (btr_exec_up(btr_parent(cwc->btrn), cmd, result) >= 0)
+ return 1;
/* Use default value */
val = arg;
break;
return 1;
}
-static void check_wav_post_select(__a_unused struct sched *s, struct task *t)
+/**
+ * Filter out the wav header, pushdown everything else.
+ *
+ * \param cwc The context of this instance.
+ *
+ * This function looks at the first \p WAV_HEADER_SIZE bytes of the input queue
+ * of the btrn of \a cwc. If they look like a wav header, the function extracts
+ * the information of interest and swallows this part of the stream. Otherwise
+ * it is pushed down to all children. In either case the rest of the input is
+ * pushed down as well.
+ *
+ * Once the first part has been processed this way, the state of the instance
+ * changes from \p CWS_NEED_HEADER to \p CWS_HAVE_HEADER or \p CWS_NO_HEADER.
+ *
+ * \return Standard.
+ */
+int check_wav_post_select(struct check_wav_context *cwc)
{
- struct check_wav_task *cwt = container_of(t, struct check_wav_task, task);
- struct btr_node *btrn = cwt->btrn;
+ struct btr_node *btrn = cwc->btrn;
unsigned char *a;
size_t sz;
int ret;
uint16_t bps; /* bits per sample */
const char *sample_formats[] = {SAMPLE_FORMATS};
- t->error = 0;
- ret = btr_node_status(btrn, cwt->min_iqs, BTR_NT_INTERNAL);
+ if (!btrn)
+ return 0;
+ ret = btr_node_status(btrn, cwc->min_iqs, BTR_NT_INTERNAL);
if (ret <= 0)
goto out;
- if (cwt->state != CWS_NEED_HEADER)
+ if (cwc->state != CWS_NEED_HEADER)
goto pushdown;
- btr_merge(btrn, cwt->min_iqs);
+ btr_merge(btrn, cwc->min_iqs);
sz = btr_next_buffer(btrn, (char **)&a);
- if (sz < cwt->min_iqs) /* file size less than WAV_HEADER_SIZE */
+ if (sz < cwc->min_iqs) /* file size less than WAV_HEADER_SIZE */
goto pushdown;
- cwt->min_iqs = 0;
+ cwc->min_iqs = 0;
/*
* The default byte ordering assumed for WAVE data files is
* little-endian. Files written using the big-endian byte ordering
if (a[0] != 'R' || a[1] != 'I' || a[2] != 'F' ||
(a[3] != 'F' && a[3] != 'X')) {
PARA_NOTICE_LOG("wav header not found\n");
- cwt->state = CWS_NO_HEADER;
- sprintf(t->status, "check wav: no header");
+ cwc->state = CWS_NO_HEADER;
goto out;
}
PARA_INFO_LOG("found wav header\n");
- cwt->state = CWS_HAVE_HEADER;
- sprintf(t->status, "check wav: have header");
+ cwc->state = CWS_HAVE_HEADER;
/* Only set those values which have not already been set. */
- cwt->channels = (unsigned)a[22];
- cwt->sample_rate = a[24] + (a[25] << 8) + (a[26] << 16) + (a[27] << 24);
- bps = a[34] + ((unsigned)a[35] << 8);
+ cwc->channels = a[22];
+ cwc->sample_rate = read_u32(a + 24);
+ bps = read_u16(a + 34);
if (bps != 8 && bps != 16) {
PARA_WARNING_LOG("%u bps not supported, assuming 16\n",
bps);
* integers, ranging from -32768 to 32767.
*/
if (bps == 8)
- cwt->sample_format = SF_U8;
+ cwc->sample_format = SF_U8;
else
- cwt->sample_format = (a[3] == 'F')?
+ cwc->sample_format = (a[3] == 'F')?
SF_S16_LE : SF_S16_BE;
- PARA_NOTICE_LOG("%dHz, %s, %s\n", cwt->sample_rate,
- cwt->channels == 1? "mono" : "stereo",
- sample_formats[cwt->sample_format]);
+ PARA_NOTICE_LOG("%uHz, %s, %s\n", cwc->sample_rate,
+ cwc->channels == 1? "mono" : "stereo",
+ sample_formats[cwc->sample_format]);
btr_consume(btrn, WAV_HEADER_LEN);
pushdown:
btr_pushdown(btrn);
out:
- t->error = ret;
if (ret < 0)
- btr_remove_node(&cwt->btrn);
+ btr_remove_node(&cwc->btrn);
+ return ret;
}
-struct check_wav_task *check_wav_init(struct sched *s, struct btr_node *parent,
- struct wav_params *params, struct btr_node **cwt_btrn)
+/**
+ * Allocate and set up a new check_wav instance.
+ *
+ * \param parent This buffer tree node will be the parent of the new node.
+ * \param child The child of the new node.
+ * \param params Default values and options.
+ * \param cw_btrn A pointer to the check wav node is returned here.
+ *
+ * This function also sets up the ->execute handler of the btrn so that all
+ * children of this node can figure out channel count, sample rate, etc.
+ *
+ * \return The (opaque) handle of the newly created check_wav instance. It is
+ * supposed to be passed to \ref check_wav_pre_select() and \ref
+ * check_wav_post_select().
+ *
+ * \sa \ref btr_new_node.
+ */
+struct check_wav_context *check_wav_init(struct btr_node *parent,
+ struct btr_node *child, struct wav_params *params,
+ struct btr_node **cw_btrn)
{
- struct check_wav_task *cwt = para_calloc(sizeof(*cwt));
-
- cwt->state = CWS_NEED_HEADER;
- cwt->min_iqs = WAV_HEADER_LEN;
- cwt->params = *params;
- cwt->btrn = btr_new_node(&(struct btr_node_description)
- EMBRACE(.name = "check_wav", .parent = parent,
- .handler = check_wav_exec, .context = cwt));
- sprintf(cwt->task.status, "check_wav");
- cwt->task.pre_select = check_wav_pre_select;
- cwt->task.post_select = check_wav_post_select;
- if (cwt_btrn)
- *cwt_btrn = cwt->btrn;
- register_task(s, &cwt->task);
- return cwt;
+ struct check_wav_context *cwc = para_calloc(sizeof(*cwc));
+
+ cwc->state = CWS_NEED_HEADER;
+ cwc->min_iqs = WAV_HEADER_LEN;
+ cwc->params = *params;
+ cwc->btrn = btr_new_node(&(struct btr_node_description)
+ EMBRACE(.name = "check_wav", .parent = parent, .child = child,
+ .handler = check_wav_exec, .context = cwc));
+ if (cw_btrn)
+ *cw_btrn = cwc->btrn;
+ return cwc;
}
-void check_wav_shutdown(struct check_wav_task *cwt)
+/**
+ * Dellocate all ressources of a check_wav instance.
+ *
+ * \param cwc Determines the instance to shut down.
+ *
+ * This function may only be called after check_wav_post_select() has returned
+ * negative.
+ */
+void check_wav_shutdown(struct check_wav_context *cwc)
{
- free(cwt);
+ free(cwc);
}
projects / paraslash.git / blobdiff