stream cipher: Allow in-place encryption.

[paraslash.git] / write.h

diff --git a/write.h b/write.h
index 102f1b25cb3c4bdaea12d0820e0e3b4af4175db8..8a60294dccbaef295987041acad36d69fa9f00f0 100644 (file)
--- a/write.h
+++ b/write.h
@@ -1,50 +1,102 @@
 /*
- * Copyright (C) 2006 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2006-2011 Andre Noll <maan@systemlinux.org>
  *
- *     This program is free software; you can redistribute it and/or modify
- *     it under the terms of the GNU General Public License as published by
- *     the Free Software Foundation; either version 2 of the License, or
- *     (at your option) any later version.
- *
- *     This program is distributed in the hope that it will be useful,
- *     but WITHOUT ANY WARRANTY; without even the implied warranty of
- *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *     GNU General Public License for more details.
- *
- *     You should have received a copy of the GNU General Public License
- *     along with this program; if not, write to the Free Software
- *     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
+ * Licensed under the GPL v2. For licencing details see COPYING.
  */
 
-/** \file write.h writer-related structures */
+/** \file write.h Writer-related structures. */
 
+/** The list of supported writers. */
 enum writer_enum {WRITER_ENUM};
 
+/**
+ * Describes one running instance of a writer.
+ */
 struct writer_node {
-       struct writer *writer;
+       /** The number of this writer. */
+       int writer_num;
+       /** Writer-specific data. */
        void *private_data;
-       int chunk_bytes;
+       /** The writer-specific configuration of this node. */
+       void *conf;
+       /** The buffer tree node associated with this writer node. */
+       struct btr_node *btrn;
+       /** The task of this writer node. */
+       struct task task;
+       /** The minimal input queue size (size of one audio sample). */
+       size_t min_iqs;
 };
 
+/** Describes one supported writer. */
 struct writer {
+       /**
+        * The init function of the writer.
+        *
+        * It must fill in all other function pointers of the given
+        * writer structure.
+        */
        void (*init)(struct writer *w);
-       int (*open)(struct writer_node *);
-       int (*write)(char *data, size_t nbytes, struct writer_node *);
+       /**
+        * The command line parser of the writer.
+        *
+        * It should check whether the command line options given by \a options
+        * are valid and return a pointer to the writer-specific configuration
+        * data determined by \a options. This function must either succeed or
+        * call exit(). Note that parse_config_or_die() might be called more
+        * than once with different values of \a options. \sa \ref
+        * free_config().
+        */
+       void *(*parse_config_or_die)(const char *options);
+       /**
+        * Dellocate all configuration resources.
+        *
+        * This should free whatever was allocated by \ref parse_config_or_die().
+        */
+       void (*free_config)(void *config);
+       /**
+        * Prepare the fd sets for select.
+        *
+        * This is called from scheduler. It may use the sched pointer to add
+        * any file descriptors or to decrease the select timeout.
+        */
+       void (*pre_select)(struct sched *s, struct task *t);
+       /**
+        * Write audio data.
+        *
+        * Called from the post_select function of the writer node's task.
+        */
+       void (*post_select)(struct sched *s, struct task *t);
+       /**
+        * Close one instance of the writer.
+        *
+        * This function is assumed to succeed.
+        */
        void (*close)(struct writer_node *);
+       /**
+        * Shutdown the writer.
+        *
+        * This is a optional function pointer used for cleaning up.
+        */
        void (*shutdown)(struct writer_node *);
+       /** The short and the log help text of this writer. */
+       struct ggo_help help;
+       /**
+        * The callback handler.
+        *
+        * Each writer may provide an ->execute callback which can be used for
+        * inter-node communication.
+        */
+       btr_command_handler execute;
 };
 
-struct writer_node_group {
-       unsigned num_writers;
-       struct writer_node *writer_nodes;
-       int *written;
-       size_t max_chunk_bytes;
-       int eof;
-};
-
-#define FOR_EACH_WRITER_NODE(i, wng) for (i = 0; i < (wng)->num_writers; i++)
+/** Loop over each supported writer. */
 #define FOR_EACH_WRITER(i) for (i = 0; i < NUM_SUPPORTED_WRITERS; i++)
 
+/** Declare the init functions of all supported writers. */
 DECLARE_WRITER_INITS;
+
+/** Array containing the name of each writer. */
 extern const char *writer_names[];
+
+/** The writer structure for each supported writer. */
 extern struct writer writers[NUM_SUPPORTED_WRITERS];