2 * Copyright (C) 2006 Andre Noll <maan@systemlinux.org>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
19 /** \file write.h writer-related structures */
21 /** the list of supported writers */
22 enum writer_enum {WRITER_ENUM};
25 * decbribes one running instance of a writer
28 /** points to the writer structure associated with this node */
29 struct writer *writer;
30 /** writer-specific data */
32 /** send that many bytes in one go */
35 struct writer_node_group *wng;
38 /** describes one supported writer */
41 * the init function of the writer
43 * It must fill in all other function pointers of the given
47 void (*init)(struct writer *w);
50 * open one instance of this writer
52 * This function should perform any work necessary to write the incoming
53 * stream. If To this aim, it may allocate its private data structure and store
54 * a pointer to that structure via the given writer_node paramenter.
56 int (*open)(struct writer_node *);
59 * write a chunk of audio data
61 * This is called from the driving application whenever a data block of \a
62 * chunk_bytes is available. It must return the number of bytes consumed from
63 * \a data on success, and negative on errors.
66 int (*write)(char *data, size_t nbytes, struct writer_node *);
67 void (*pre_select)(struct sched *s, struct task *t);
68 void (*post_select)(struct sched *s, struct task *t);
70 * close one instance of the writer
72 * This function is assumed to succeed.
74 void (*close)(struct writer_node *);
78 * This is a optional function pointer used for cleaning
81 void (*shutdown)(struct writer_node *);
85 * describes a set of writer nodes that all write the same stream.
87 struct writer_node_group {
88 /** number of nodes belonging to this group */
90 /** array of pointers to the corresponding writer nodes */
91 struct writer_node *writer_nodes;
92 /** keeps track of how many bytes have been written by each node */
94 /** the maximum of the chunk_bytes values of the writer nodes in this group */
95 size_t max_chunk_bytes;
96 /** non-zero if end of file was encountered */
103 /** loop over each writer node in a writer group */
104 #define FOR_EACH_WRITER_NODE(i, wng) for (i = 0; i < (wng)->num_writers; i++)
105 /** loop over each supported writer */
106 #define FOR_EACH_WRITER(i) for (i = 0; i < NUM_SUPPORTED_WRITERS; i++)
108 /** declare the init functions of all supported writers */
109 DECLARE_WRITER_INITS;
111 /** array containing the name of each writer */
112 extern const char *writer_names[];
114 /** the writer structure for each supported writer */
115 extern struct writer writers[NUM_SUPPORTED_WRITERS];