aft.c: Silence scan-build warning.

[paraslash.git] / filter_common.c

diff --git a/filter_common.c b/filter_common.c
index 06a1f52bf15012c556b7b3443e8a5e51b5ac4f16..ffb2199b60e75836c345f09ef8cac1b1202d1956 100644 (file)
--- a/filter_common.c
+++ b/filter_common.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2005-2010 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005-2012 Andre Noll <maan@systemlinux.org>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -8,8 +8,6 @@
 
 #include <regex.h>
 #include <sys/types.h>
-#include <dirent.h>
-#include <stdbool.h>
 
 #include "para.h"
 #include "list.h"
@@ -109,6 +107,11 @@ int check_filter_arg(char *fa, void **conf)
        return -E_UNSUPPORTED_FILTER;
 }
 
+/**
+ * Print help text of each filter to stdout.
+ *
+ * \param detailed If non-zero, print detailed help.
+ */
 void print_filter_helps(int detailed)
 {
        int i;
@@ -128,6 +131,17 @@ void print_filter_helps(int detailed)
        }
 }
 
+/**
+ * Set select timeout of the the scheduler.
+ *
+ * \param s The scheduler.
+ * \param t The task struct of this filter.
+ *
+ * This looks at the status of the btr node of the filter. If data is available
+ * in the input queue of the filter, or if an error occured, a minimal timeout
+ * for the next select call is requested from the scheduler. Otherwise the
+ * scheduler timeout is left unchanged.
+ */
 void generic_filter_pre_select(struct sched *s, struct task *t)
 {
        struct filter_node *fn = container_of(t, struct filter_node, task);
@@ -136,3 +150,45 @@ void generic_filter_pre_select(struct sched *s, struct task *t)
        if (btr_node_status(fn->btrn, fn->min_iqs, BTR_NT_INTERNAL) != 0)
                sched_min_delay(s);
 }
+
+#ifdef WORDS_BIGENDIAN
+#define DECODER_SAMPLE_FORMAT SF_S16_BE
+#else
+#define DECODER_SAMPLE_FORMAT SF_S16_LE
+#endif
+
+/**
+ * Execute a btr command for a decoder.
+ *
+ * The buffer tree nodes of the writers ask the parent nodes about sample_rate,
+ * channels count and sample format. This function is called by all decoders to
+ * answer these queries.
+ *
+ * \param cmd The command to be executed by the child node.
+ * \param sample_rate Known to the decoder.
+ * \param channels Known to the decoder.
+ * \param result Ascii representation on the answer is stored here.
+ *
+ * \return Standard.
+ */
+int decoder_execute(const char *cmd, unsigned sample_rate, unsigned channels,
+               char **result)
+{
+       if (!strcmp(cmd, "sample_rate")) {
+               if (sample_rate == 0)
+                       return -E_BTR_NAVAIL;
+               *result = make_message("%u", sample_rate);
+               return 1;
+       }
+       if (!strcmp(cmd, "channels")) {
+               if (channels == 0)
+                       return -E_BTR_NAVAIL;
+               *result = make_message("%u", channels);
+               return 1;
+       }
+       if (!strcmp(cmd, "sample_format")) {
+               *result = make_message("%u", DECODER_SAMPLE_FORMAT);
+               return 1;
+       }
+       return -ERRNO_TO_PARA_ERROR(ENOTSUP);
+}