From: Andre Noll <maan@tuebingen.mpg.de>
Date: Mon, 2 Jan 2023 13:43:42 +0000 (+0100)
Subject: Constify buffer tree API.
X-Git-Url: http://git.tue.mpg.de/?a=commitdiff_plain;h=4dfa81fee689335545bd16322cad6dbf84faa748;p=paraslash.git

Constify buffer tree API.

A lot of functions of the buffer tree API don't modify the memory
referenced by the pointers passed. This patch marks these pointer
arguments as constant.
---

diff --git a/aacdec_filter.c b/aacdec_filter.c
index 87a7900a..ab07be8f 100644
--- a/aacdec_filter.c
+++ b/aacdec_filter.c
@@ -41,7 +41,8 @@ struct private_aacdec_data {
 	unsigned int sample_rate;
 };
 
-static int aacdec_execute(struct btr_node *btrn, const char *cmd, char **result)
+static int aacdec_execute(const struct btr_node *btrn, const char *cmd,
+		char **result)
 {
 	struct filter_node *fn = btr_context(btrn);
 	struct private_aacdec_data *padd = fn->private_data;
diff --git a/afh_recv.c b/afh_recv.c
index 8449e787..687b77d9 100644
--- a/afh_recv.c
+++ b/afh_recv.c
@@ -30,7 +30,7 @@ struct private_afh_recv_data {
 	void *afh_context;
 };
 
-static int afh_execute(struct btr_node *btrn, const char *cmd, char **result)
+static int afh_execute(const struct btr_node *btrn, const char *cmd, char **result)
 {
 	struct receiver_node *rn = btr_context(btrn);
 	struct private_afh_recv_data *pard = rn->private_data;
diff --git a/buffer_tree.c b/buffer_tree.c
index 36a7e6e1..255dc475 100644
--- a/buffer_tree.c
+++ b/buffer_tree.c
@@ -103,12 +103,12 @@ void btr_pool_free(struct btr_pool *btrp)
  * \return The same value which was passed during creation time to
  * btr_pool_new().
  */
-size_t btr_pool_size(struct btr_pool *btrp)
+size_t btr_pool_size(const struct btr_pool *btrp)
 {
 	return btrp->area_end - btrp->area_start;
 }
 
-static size_t btr_pool_filled(struct btr_pool *btrp)
+static size_t btr_pool_filled(const struct btr_pool *btrp)
 {
 	if (!btrp->whead)
 		return btr_pool_size(btrp);
@@ -129,7 +129,7 @@ static size_t btr_pool_filled(struct btr_pool *btrp)
  * the largest contiguous buffer that can currently be allocated from the
  * buffer pool.
  */
-size_t btr_pool_unused(struct btr_pool *btrp)
+size_t btr_pool_unused(const struct btr_pool *btrp)
 {
 	return btr_pool_size(btrp) - btr_pool_filled(btrp);
 }
@@ -138,7 +138,7 @@ size_t btr_pool_unused(struct btr_pool *btrp)
  * Return maximal size available for one read. This is
  * smaller than the value returned by btr_pool_unused().
  */
-static size_t btr_pool_available(struct btr_pool *btrp)
+static size_t btr_pool_available(const struct btr_pool *btrp)
 {
 	if (!btrp->whead)
 		return 0;
@@ -156,7 +156,7 @@ static size_t btr_pool_available(struct btr_pool *btrp)
  * \return The maximal amount of bytes that may be written to the returned
  * buffer.
  */
-size_t btr_pool_get_buffer(struct btr_pool *btrp, char **result)
+size_t btr_pool_get_buffer(const struct btr_pool *btrp, char **result)
 {
 	if (result)
 		*result = btrp->whead;
@@ -174,7 +174,7 @@ size_t btr_pool_get_buffer(struct btr_pool *btrp, char **result)
  * consists of two buffers. If this function returns the value n, then n
  * elements of \a iov are initialized.
  */
-int btr_pool_get_buffers(struct btr_pool *btrp, struct iovec iov[2])
+int btr_pool_get_buffers(const struct btr_pool *btrp, struct iovec iov[2])
 {
 	size_t sz, unused;
 	char *buf;
@@ -322,7 +322,7 @@ static void dealloc_buffer(struct btr_buffer *btrb)
 		free(btrb->buf);
 }
 
-static struct btr_buffer_reference *get_first_input_br(struct btr_node *btrn)
+static struct btr_buffer_reference *get_first_input_br(const struct btr_node *btrn)
 {
 	if (list_empty(&btrn->input_queue))
 		return NULL;
@@ -330,7 +330,7 @@ static struct btr_buffer_reference *get_first_input_br(struct btr_node *btrn)
 		struct btr_buffer_reference, node);
 }
 
-static struct btr_buffer_reference *get_last_input_br(struct btr_node *btrn)
+static struct btr_buffer_reference *get_last_input_br(const struct btr_node *btrn)
 {
 	if (list_empty(&btrn->input_queue))
 		return NULL;
@@ -562,7 +562,7 @@ void btr_pushdown_one(struct btr_node *btrn)
  *
  * \return True if this node has no children. False otherwise.
  */
-static bool btr_no_children(struct btr_node *btrn)
+static bool btr_no_children(const struct btr_node *btrn)
 {
 	return list_empty(&btrn->children);
 }
@@ -579,7 +579,7 @@ static bool btr_no_children(struct btr_node *btrn)
  * After a (non-leaf) node was removed removed from the tree, the function
  * returns true for all child nodes.
  */
-bool btr_no_parent(struct btr_node *btrn)
+bool btr_no_parent(const struct btr_node *btrn)
 {
 	return !btrn->parent;
 }
@@ -602,7 +602,7 @@ bool btr_no_parent(struct btr_node *btrn)
  *
  * \return True if \a btrn has no siblings.
  */
-bool btr_inplace_ok(struct btr_node *btrn)
+bool btr_inplace_ok(const struct btr_node *btrn)
 {
 	struct btr_buffer_reference *br;
 	FOR_EACH_BUFFER_REF(br, btrn) {
@@ -615,12 +615,13 @@ bool btr_inplace_ok(struct btr_node *btrn)
 	return true;
 }
 
-static inline size_t br_available_bytes(struct btr_buffer_reference *br)
+static inline size_t br_available_bytes(const struct btr_buffer_reference *br)
 {
 	return br->btrb->size - br->consumed;
 }
 
-static size_t btr_get_buffer_by_reference(struct btr_buffer_reference *br, char **buf)
+static size_t btr_get_buffer_by_reference(const struct btr_buffer_reference *br,
+		char **buf)
 {
 	if (buf)
 		*buf = br->btrb->buf + br->consumed;
@@ -647,7 +648,8 @@ static size_t btr_get_buffer_by_reference(struct btr_buffer_reference *br, char
  * to by \a btrn, the function returns zero and the value of \a bufp is
  * undefined.
  */
-size_t btr_next_buffer_omit(struct btr_node *btrn, size_t omit, char **bufp)
+size_t btr_next_buffer_omit(const struct btr_node *btrn, size_t omit,
+		char **bufp)
 {
 	struct btr_buffer_reference *br;
 	size_t wrap_count, sz, rv = 0;
@@ -712,7 +714,7 @@ out:
  * The call of this function is is equivalent to calling \ref
  * btr_next_buffer_omit() with an \a omit value of zero.
  */
-size_t btr_next_buffer(struct btr_node *btrn, char **bufp)
+size_t btr_next_buffer(const struct btr_node *btrn, char **bufp)
 {
 	return btr_next_buffer_omit(btrn, 0, bufp);
 }
@@ -844,7 +846,7 @@ out:
  * This simply iterates over all buffer references in the input queue and
  * returns the sum of the sizes of all references.
  */
-size_t btr_get_input_queue_size(struct btr_node *btrn)
+size_t btr_get_input_queue_size(const struct btr_node *btrn)
 {
 	struct btr_buffer_reference *br;
 	size_t size = 0, wrap_consumed = 0;
@@ -861,7 +863,7 @@ size_t btr_get_input_queue_size(struct btr_node *btrn)
 	return size;
 }
 
-static bool min_iqs_available(size_t min_iqs, struct btr_node *btrn)
+static bool min_iqs_available(size_t min_iqs, const struct btr_node *btrn)
 {
 	struct btr_buffer_reference *br;
 	size_t have = 0, wrap_consumed = 0;
@@ -919,7 +921,7 @@ void btr_splice_out_node(struct btr_node **btrnp)
  * \return This function iterates over all children of the given node and
  * returns the size of the largest input queue.
  */
-size_t btr_get_output_queue_size(struct btr_node *btrn)
+size_t btr_get_output_queue_size(const struct btr_node *btrn)
 {
 	size_t max_size = 0;
 	struct btr_node *ch;
@@ -947,7 +949,7 @@ size_t btr_get_output_queue_size(struct btr_node *btrn)
  *
  * \sa \ref receiver::execute, \ref filter::execute, \ref writer::execute.
  */
-int btr_exec_up(struct btr_node *btrn, const char *command, char **value_result)
+int btr_exec_up(const struct btr_node *btrn, const char *command, char **value_result)
 {
 	int ret;
 
@@ -977,12 +979,12 @@ int btr_exec_up(struct btr_node *btrn, const char *command, char **value_result)
  *
  * \sa \ref btr_new_node(), struct \ref btr_node_description.
  */
-void *btr_context(struct btr_node *btrn)
+void *btr_context(const struct btr_node *btrn)
 {
 	return btrn->context;
 }
 
-static bool need_buffer_pool_merge(struct btr_node *btrn)
+static bool need_buffer_pool_merge(const struct btr_node *btrn)
 {
 	struct btr_buffer_reference *br = get_first_input_br(btrn);
 
@@ -1157,7 +1159,7 @@ void btr_merge(struct btr_node *btrn, size_t dest_size)
 	}
 }
 
-static bool btr_eof(struct btr_node *btrn)
+static bool btr_eof(const struct btr_node *btrn)
 {
 	char *buf;
 	size_t len = btr_next_buffer(btrn, &buf);
@@ -1165,7 +1167,7 @@ static bool btr_eof(struct btr_node *btrn)
 	return (len == 0 && btr_no_parent(btrn));
 }
 
-static void log_tree_recursively(struct btr_node *btrn, int loglevel, int depth)
+static void log_tree_recursively(const struct btr_node *btrn, int loglevel, int depth)
 {
 	struct btr_node *ch;
 	const char spaces[] = "                 ", *space = spaces + 16 - depth;
@@ -1183,7 +1185,7 @@ static void log_tree_recursively(struct btr_node *btrn, int loglevel, int depth)
  * \param btrn Start logging at this node.
  * \param loglevel Set severity with which the tree should be logged.
  */
-void btr_log_tree(struct btr_node *btrn, int loglevel)
+void btr_log_tree(const struct btr_node *btrn, int loglevel)
 {
 	return log_tree_recursively(btrn, loglevel, 0);
 }
@@ -1243,7 +1245,7 @@ struct btr_node *btr_search_node(const char *name, struct btr_node *root)
  * btrn, the function also returns zero in order to bound the memory usage of
  * the buffer tree.
  */
-int btr_node_status(struct btr_node *btrn, size_t min_iqs,
+int btr_node_status(const struct btr_node *btrn, size_t min_iqs,
 	enum btr_node_type type)
 {
 	if (type != BTR_NT_LEAF && btr_no_children(btrn))
@@ -1268,7 +1270,7 @@ int btr_node_status(struct btr_node *btrn, size_t min_iqs,
  *
  * Mainly useful for the time display of para_audiod.
  */
-void btr_get_node_start(struct btr_node *btrn, struct timeval *tv)
+void btr_get_node_start(const struct btr_node *btrn, struct timeval *tv)
 {
 	*tv = btrn->start;
 }
@@ -1283,7 +1285,7 @@ void btr_get_node_start(struct btr_node *btrn, struct timeval *tv)
  * \return The parent of \a btrn, or \p NULL if \a btrn is the
  * root node of the buffer tree.
  */
-struct btr_node *btr_parent(struct btr_node *btrn)
+struct btr_node *btr_parent(const struct btr_node *btrn)
 {
 	return btrn->parent;
 }
diff --git a/buffer_tree.h b/buffer_tree.h
index 34535219..5eb3d6e5 100644
--- a/buffer_tree.h
+++ b/buffer_tree.h
@@ -131,7 +131,7 @@ enum btr_node_type {
  * know the sample rate of its input known to e.g. the mp3dec node further up
  * in the buffer tree.
  */
-typedef int (*btr_command_handler)(struct btr_node *btrn,
+typedef int (*btr_command_handler)(const struct btr_node *btrn,
 		const char *command, char **result);
 
 /**
@@ -166,38 +166,38 @@ struct btr_node_description {
 	void *context;
 };
 
-size_t btr_pool_size(struct btr_pool *btrp);
+size_t btr_pool_size(const struct btr_pool *btrp);
 struct btr_pool *btr_pool_new(const char *name, size_t area_size);
 void btr_pool_free(struct btr_pool *btrp);
-size_t btr_pool_get_buffer(struct btr_pool *btrp, char **result);
-int btr_pool_get_buffers(struct btr_pool *btrp, struct iovec iov[2]);
+size_t btr_pool_get_buffer(const struct btr_pool *btrp, char **result);
+int btr_pool_get_buffers(const struct btr_pool *btrp, struct iovec iov[2]);
 void btr_add_output_pool(struct btr_pool *btrp, size_t size,
 	struct btr_node *btrn);
-size_t btr_pool_unused(struct btr_pool *btrp);
+size_t btr_pool_unused(const struct btr_pool *btrp);
 void btr_copy(const void *src, size_t n, struct btr_pool *btrp,
 	struct btr_node *btrn);
-
 struct btr_node *btr_new_node(struct btr_node_description *bnd);
 void btr_remove_node(struct btr_node **btrnp);
 void btr_add_output(char *buf, size_t size, struct btr_node *btrn);
 void btr_add_output_dont_free(const char *buf, size_t size, struct btr_node *btrn);
-size_t btr_get_input_queue_size(struct btr_node *btrn);
-size_t btr_get_output_queue_size(struct btr_node *btrn);
-bool btr_no_parent(struct btr_node *btrn);
-size_t btr_next_buffer(struct btr_node *btrn, char **bufp);
-size_t btr_next_buffer_omit(struct btr_node *btrn, size_t omit, char **bufp);
+size_t btr_get_input_queue_size(const struct btr_node *btrn);
+size_t btr_get_output_queue_size(const struct btr_node *btrn);
+bool btr_no_parent(const struct btr_node *btrn);
+size_t btr_next_buffer(const struct btr_node *btrn, char **bufp);
+size_t btr_next_buffer_omit(const struct btr_node *btrn, size_t omit,
+		char **bufp);
 void btr_consume(struct btr_node *btrn, size_t numbytes);
-int btr_exec_up(struct btr_node *btrn, const char *command, char **value_result);
+int btr_exec_up(const struct btr_node *btrn, const char *command, char **value_result);
 void btr_splice_out_node(struct btr_node **btrnp);
 void btr_pushdown(struct btr_node *btrn);
-void *btr_context(struct btr_node *btrn);
+void *btr_context(const struct btr_node *btrn);
 void btr_merge(struct btr_node *btrn, size_t dest_size);
-void btr_log_tree(struct btr_node *btrn, int ll);
+void btr_log_tree(const struct btr_node *btrn, int ll);
 void btr_pushdown_one(struct btr_node *btrn);
-bool btr_inplace_ok(struct btr_node *btrn);
-int btr_node_status(struct btr_node *btrn, size_t min_iqs,
+bool btr_inplace_ok(const struct btr_node *btrn);
+int btr_node_status(const struct btr_node *btrn, size_t min_iqs,
 		enum btr_node_type type);
-void btr_get_node_start(struct btr_node *btrn, struct timeval *tv);
+void btr_get_node_start(const struct btr_node *btrn, struct timeval *tv);
 struct btr_node *btr_search_node(const char *name, struct btr_node *root);
 void btr_drain(struct btr_node *btrn);
-struct btr_node *btr_parent(struct btr_node *btrn);
+struct btr_node *btr_parent(const struct btr_node *btrn);
diff --git a/check_wav.c b/check_wav.c
index 3789f30a..cb39eb54 100644
--- a/check_wav.c
+++ b/check_wav.c
@@ -54,7 +54,7 @@ void check_wav_pre_monitor(struct sched *s, struct check_wav_context *cwc)
 		sched_min_delay(s);
 }
 
-static int check_wav_exec(struct btr_node *btrn, const char *cmd, char **result)
+static int check_wav_exec(const struct btr_node *btrn, const char *cmd, char **result)
 {
 	struct check_wav_context *cwc = btr_context(btrn);
 	int val, header_val, given, arg;
diff --git a/flacdec_filter.c b/flacdec_filter.c
index fb8ebf15..bc3a678b 100644
--- a/flacdec_filter.c
+++ b/flacdec_filter.c
@@ -187,7 +187,7 @@ static int flacdec_init(struct filter_node *fn)
 	return -E_FLACDEC_DECODER_INIT;
 }
 
-static int flacdec_execute(struct btr_node *btrn, const char *cmd,
+static int flacdec_execute(const struct btr_node *btrn, const char *cmd,
 		char **result)
 {
 	struct filter_node *fn = btr_context(btrn);
diff --git a/mp3dec_filter.c b/mp3dec_filter.c
index cf3e5d4b..d4d4712f 100644
--- a/mp3dec_filter.c
+++ b/mp3dec_filter.c
@@ -175,7 +175,8 @@ static void mp3dec_open(struct filter_node *fn)
 		mad_stream_options(&pmd->stream, MAD_OPTION_IGNORECRC);
 }
 
-static int mp3dec_execute(struct btr_node *btrn, const char *cmd, char **result)
+static int mp3dec_execute(const struct btr_node *btrn, const char *cmd,
+		char **result)
 {
 	struct filter_node *fn = btr_context(btrn);
 	struct private_mp3dec_data *pmd = fn->private_data;
diff --git a/oggdec_filter.c b/oggdec_filter.c
index b1aec4bc..91c18c48 100644
--- a/oggdec_filter.c
+++ b/oggdec_filter.c
@@ -107,7 +107,8 @@ static void ogg_close(struct filter_node *fn)
 	fn->private_data = NULL;
 }
 
-static int oggdec_execute(struct btr_node *btrn, const char *cmd, char **result)
+static int oggdec_execute(const struct btr_node *btrn, const char *cmd,
+		char **result)
 {
 	struct filter_node *fn = btr_context(btrn);
 	struct private_oggdec_data *pod = fn->private_data;
diff --git a/opusdec_filter.c b/opusdec_filter.c
index f36990fa..504ba0e8 100644
--- a/opusdec_filter.c
+++ b/opusdec_filter.c
@@ -75,7 +75,7 @@ struct opusdec_context {
 	ogg_int32_t opus_serialno;
 };
 
-static int opusdec_execute(struct btr_node *btrn, const char *cmd,
+static int opusdec_execute(const struct btr_node *btrn, const char *cmd,
 		char **result)
 {
 	struct filter_node *fn = btr_context(btrn);
diff --git a/resample_filter.c b/resample_filter.c
index 72cb3f62..6d4599a8 100644
--- a/resample_filter.c
+++ b/resample_filter.c
@@ -28,7 +28,8 @@ struct resample_context {
 	struct check_wav_context *cwc;
 };
 
-static int resample_execute(struct btr_node *btrn, const char *cmd, char **result)
+static int resample_execute(const struct btr_node *btrn, const char *cmd,
+		char **result)
 {
 	struct filter_node *fn = btr_context(btrn);
 	struct resample_context *ctx = fn->private_data;
diff --git a/spxdec_filter.c b/spxdec_filter.c
index 08eac02a..ce72125e 100644
--- a/spxdec_filter.c
+++ b/spxdec_filter.c
@@ -102,7 +102,7 @@ static void speexdec_close(struct filter_node *fn)
 	fn->private_data = NULL;
 }
 
-static int speexdec_execute(struct btr_node *btrn, const char *cmd,
+static int speexdec_execute(const struct btr_node *btrn, const char *cmd,
 		char **result)
 {
 	struct filter_node *fn = btr_context(btrn);
diff --git a/wmadec_filter.c b/wmadec_filter.c
index f2ca273c..5b3d9874 100644
--- a/wmadec_filter.c
+++ b/wmadec_filter.c
@@ -1147,7 +1147,8 @@ static void wmadec_close(struct filter_node *fn)
 	fn->private_data = NULL;
 }
 
-static int wmadec_execute(struct btr_node *btrn, const char *cmd, char **result)
+static int wmadec_execute(const struct btr_node *btrn, const char *cmd,
+		char **result)
 {
 	struct filter_node *fn = btr_context(btrn);
 	struct private_wmadec_data *pwd = fn->private_data;