Add SerdSinkInterface and hide implementations

8 files changed, 116 insertions, 162 deletions

diff --git a/serd/serd.h b/serd/serd.h
index 6add5a78..4e9b5d48 100644
--- a/serd/serd.h
+++ b/serd/serd.h
@@ -683,6 +683,17 @@ typedef SerdStatus (*SerdEndSink)(void*           handle,
                                   const SerdNode* node);
 
 /**
+   An interface that receives a stream of RDF data.
+*/
+typedef struct SerdSinkInterface {
+	void*             handle;
+	SerdBaseSink      base;
+	SerdPrefixSink    prefix;
+	SerdStatementSink statement;
+	SerdEndSink       end;
+} SerdSinkInterface;
+
+/**
    @}
    @name Environment
    @{
@@ -789,13 +800,8 @@ serd_env_foreach(const SerdEnv* env,
 */
 SERD_API
 SerdReader*
-serd_reader_new(SerdSyntax        syntax,
-                void*             handle,
-                void              (*free_handle)(void*),
-                SerdBaseSink      base_sink,
-                SerdPrefixSink    prefix_sink,
-                SerdStatementSink statement_sink,
-                SerdEndSink       end_sink);
+serd_reader_new(SerdSyntax               syntax,
+                const SerdSinkInterface* sink);
 
 /**
    Enable or disable strict parsing.
@@ -953,6 +959,13 @@ void
 serd_writer_free(SerdWriter* writer);
 
 /**
+   Return a sink interface that emits statements via `writer`.
+*/
+SERD_API
+const SerdSinkInterface*
+serd_writer_get_sink_interface(SerdWriter* writer);
+
+/**
    Return the env used by `writer`.
 */
 SERD_API
@@ -1037,41 +1050,6 @@ serd_writer_set_root_uri(SerdWriter*     writer,
                          const SerdNode* uri);
 
 /**
-   Set a namespace prefix (and emit directive if applicable).
-
-   Note this function can be safely casted to SerdPrefixSink.
-*/
-SERD_API
-SerdStatus
-serd_writer_set_prefix(SerdWriter*     writer,
-                       const SerdNode* name,
-                       const SerdNode* uri);
-
-/**
-   Write a statement.
-
-   Note this function can be safely casted to SerdStatementSink.
-*/
-SERD_API
-SerdStatus
-serd_writer_write_statement(SerdWriter*        writer,
-                            SerdStatementFlags flags,
-                            const SerdNode*    graph,
-                            const SerdNode*    subject,
-                            const SerdNode*    predicate,
-                            const SerdNode*    object);
-
-/**
-   Mark the end of an anonymous node's description.
-
-   Note this function can be safely casted to SerdEndSink.
-*/
-SERD_API
-SerdStatus
-serd_writer_end_anon(SerdWriter*     writer,
-                     const SerdNode* node);
-
-/**
    Finish a write.
 */
 SERD_API
diff --git a/src/n3.c b/src/n3.c
index 7b91f62d..a0d2ef5e 100644
--- a/src/n3.c
+++ b/src/n3.c
@@ -953,8 +953,8 @@ read_anon(SerdReader* reader, ReadContext ctx, bool subject, Ref* dest)
 			return r_err(reader, SERD_ERR_BAD_SYNTAX, "`.' inside blank\n");
 		}
 		read_ws_star(reader);
-		if (reader->end_sink) {
-			reader->end_sink(reader->handle, deref(reader, *dest));
+		if (reader->sink->end) {
+			reader->sink->end(reader->sink->handle, deref(reader, *dest));
 		}
 		*ctx.flags = old_flags;
 	}
@@ -1248,8 +1248,8 @@ read_base(SerdReader* reader, bool sparql, bool token)
 	Ref uri;
 	read_ws_star(reader);
 	TRY_RET(uri = read_IRIREF(reader));
-	if (reader->base_sink) {
-		reader->base_sink(reader->handle, deref(reader, uri));
+	if (reader->sink->base) {
+		reader->sink->base(reader->sink->handle, deref(reader, uri));
 	}
 	pop_node(reader, uri);
 
@@ -1288,10 +1288,10 @@ read_prefixID(SerdReader* reader, bool sparql, bool token)
 		return false;
 	}
 
-	if (reader->prefix_sink) {
-		ret = !reader->prefix_sink(reader->handle,
-		                           deref(reader, name),
-		                           deref(reader, uri));
+	if (reader->sink->prefix) {
+		ret = !reader->sink->prefix(reader->sink->handle,
+		                            deref(reader, name),
+		                            deref(reader, uri));
 	}
 	pop_node(reader, uri);
 	pop_node(reader, name);
diff --git a/src/reader.c b/src/reader.c
index c02a2a13..7e05d25c 100644
--- a/src/reader.c
+++ b/src/reader.c
@@ -121,9 +121,9 @@ emit_statement(SerdReader* reader, ReadContext ctx, Ref o, Ref d, Ref l)
 	if (!graph && reader->default_graph) {
 		graph = reader->default_graph;
 	}
-	bool ret = !reader->statement_sink ||
-		!reader->statement_sink(
-			reader->handle, *ctx.flags, graph,
+	bool ret = !reader->sink->statement ||
+		!reader->sink->statement(
+			reader->sink->handle, *ctx.flags, graph,
 			deref(reader, ctx.subject), deref(reader, ctx.predicate),
 			deref(reader, o));
 	*ctx.flags &= SERD_ANON_CONT|SERD_LIST_CONT;  // Preserve only cont flags
@@ -157,26 +157,16 @@ serd_reader_read_document(SerdReader* reader)
 
 SERD_API
 SerdReader*
-serd_reader_new(SerdSyntax        syntax,
-                void*             handle,
-                void              (*free_handle)(void*),
-                SerdBaseSink      base_sink,
-                SerdPrefixSink    prefix_sink,
-                SerdStatementSink statement_sink,
-                SerdEndSink       end_sink)
+serd_reader_new(SerdSyntax               syntax,
+                const SerdSinkInterface* sink)
 {
-	SerdReader*  me  = (SerdReader*)calloc(1, sizeof(SerdReader));
-	me->handle           = handle;
-	me->free_handle      = free_handle;
-	me->base_sink        = base_sink;
-	me->prefix_sink      = prefix_sink;
-	me->statement_sink   = statement_sink;
-	me->end_sink         = end_sink;
-	me->default_graph    = NULL;
-	me->stack            = serd_stack_new(SERD_PAGE_SIZE);
-	me->syntax           = syntax;
-	me->next_id          = 1;
-	me->strict           = true;
+	SerdReader* me = (SerdReader*)calloc(1, sizeof(SerdReader));
+	me->sink          = sink;
+	me->default_graph = NULL;
+	me->stack         = serd_stack_new(SERD_PAGE_SIZE);
+	me->syntax        = syntax;
+	me->next_id       = 1;
+	me->strict        = true;
 
 	me->rdf_first = push_node(me, SERD_URI, NS_RDF "first", 48);
 	me->rdf_rest  = push_node(me, SERD_URI, NS_RDF "rest", 47);
@@ -216,20 +206,10 @@ serd_reader_free(SerdReader* reader)
 #endif
 	free(reader->stack.buf);
 	free(reader->bprefix);
-	if (reader->free_handle) {
-		reader->free_handle(reader->handle);
-	}
 	free(reader);
 }
 
 SERD_API
-void*
-serd_reader_get_handle(const SerdReader* reader)
-{
-	return reader->handle;
-}
-
-SERD_API
 void
 serd_reader_add_blank_prefix(SerdReader* reader,
                              const char* prefix)
diff --git a/src/reader.h b/src/reader.h
index 842ba8b8..ec2532b0 100644
--- a/src/reader.h
+++ b/src/reader.h
@@ -46,31 +46,26 @@ typedef struct {
 } ReadContext;
 
 struct SerdReaderImpl {
-	void*             handle;
-	void              (*free_handle)(void* ptr);
-	SerdBaseSink      base_sink;
-	SerdPrefixSink    prefix_sink;
-	SerdStatementSink statement_sink;
-	SerdEndSink       end_sink;
-	SerdErrorSink     error_sink;
-	void*             error_handle;
-	Ref               rdf_first;
-	Ref               rdf_rest;
-	Ref               rdf_nil;
-	SerdNode*         default_graph;
-	SerdByteSource    source;
-	SerdStack         stack;
-	SerdSyntax        syntax;
-	unsigned          next_id;
-	SerdStatus        status;
-	uint8_t*          buf;
-	char*             bprefix;
-	size_t            bprefix_len;
-	bool              strict;     ///< True iff strict parsing
-	bool              seen_genid;
+	const SerdSinkInterface* sink;
+	SerdErrorSink            error_sink;
+	void*                    error_handle;
+	Ref                      rdf_first;
+	Ref                      rdf_rest;
+	Ref                      rdf_nil;
+	SerdNode*                default_graph;
+	SerdByteSource           source;
+	SerdStack                stack;
+	SerdSyntax               syntax;
+	unsigned                 next_id;
+	SerdStatus               status;
+	uint8_t*                 buf;
+	char*                    bprefix;
+	size_t                   bprefix_len;
+	bool                     strict; ///< True iff strict parsing
+	bool                     seen_genid;
 #ifdef SERD_STACK_CHECK
-	Ref*              allocs;     ///< Stack of push offsets
-	size_t            n_allocs;   ///< Number of stack pushes
+	Ref*                     allocs; ///< Stack of push offsets
+	size_t                   n_allocs; ///< Number of stack pushes
 #endif
 };
 
diff --git a/src/serdi.c b/src/serdi.c
index 134cd369..dc8e3207 100644
--- a/src/serdi.c
+++ b/src/serdi.c
@@ -277,11 +277,7 @@ main(int argc, char** argv)
 		env, &base_uri, serd_file_sink, out_fd);
 
 	SerdReader* reader = serd_reader_new(
-		input_syntax, writer, NULL,
-		(SerdBaseSink)serd_writer_set_base_uri,
-		(SerdPrefixSink)serd_writer_set_prefix,
-		(SerdStatementSink)serd_writer_write_statement,
-		(SerdEndSink)serd_writer_end_anon);
+		input_syntax, serd_writer_get_sink_interface(writer));
 
 	serd_reader_set_strict(reader, !lax);
 	if (quiet) {
diff --git a/src/writer.c b/src/writer.c
index f75c23a0..2671ba7d 100644
--- a/src/writer.c
+++ b/src/writer.c
@@ -89,24 +89,25 @@ static const SepRule rules[] = {
 };
 
 struct SerdWriterImpl {
-	SerdSyntax    syntax;
-	SerdStyle     style;
-	SerdEnv*      env;
-	SerdNode*     root_node;
-	SerdURI       root_uri;
-	SerdURI       base_uri;
-	SerdStack     anon_stack;
-	SerdByteSink  byte_sink;
-	SerdErrorSink error_sink;
-	void*         error_handle;
-	WriteContext  context;
-	SerdNode*     list_subj;
-	unsigned      list_depth;
-	unsigned      indent;
-	uint8_t*      bprefix;
-	size_t        bprefix_len;
-	Sep           last_sep;
-	bool          empty;
+	SerdSinkInterface iface;
+	SerdSyntax        syntax;
+	SerdStyle         style;
+	SerdEnv*          env;
+	SerdNode*         root_node;
+	SerdURI           root_uri;
+	SerdURI           base_uri;
+	SerdStack         anon_stack;
+	SerdByteSink      byte_sink;
+	SerdErrorSink     error_sink;
+	void*             error_handle;
+	WriteContext      context;
+	SerdNode*         list_subj;
+	unsigned          list_depth;
+	unsigned          indent;
+	uint8_t*          bprefix;
+	size_t            bprefix_len;
+	Sep               last_sep;
+	bool              empty;
 };
 
 typedef enum {
@@ -114,6 +115,11 @@ typedef enum {
 	WRITE_LONG_STRING
 } TextContext;
 
+static SerdStatus
+serd_writer_set_prefix(SerdWriter*     writer,
+                       const SerdNode* name,
+                       const SerdNode* uri);
+
 static bool
 write_node(SerdWriter*        writer,
            const SerdNode*    node,
@@ -693,8 +699,7 @@ write_list_obj(SerdWriter*        writer,
 	return false;
 }
 
-SERD_API
-SerdStatus
+static SerdStatus
 serd_writer_write_statement(SerdWriter*        writer,
                             SerdStatementFlags flags,
                             const SerdNode*    graph,
@@ -827,8 +832,7 @@ serd_writer_write_statement(SerdWriter*        writer,
 	return SERD_SUCCESS;
 }
 
-SERD_API
-SerdStatus
+static SerdStatus
 serd_writer_end_anon(SerdWriter*     writer,
                      const SerdNode* node)
 {
@@ -893,6 +897,13 @@ serd_writer_new(SerdSyntax     syntax,
 	writer->empty        = true;
 	writer->byte_sink    = serd_byte_sink_new(
 		ssink, stream, (style & SERD_STYLE_BULK) ? SERD_PAGE_SIZE : 1);
+
+	writer->iface.handle    = writer;
+	writer->iface.base      = (SerdBaseSink)serd_writer_set_base_uri;
+	writer->iface.prefix    = (SerdPrefixSink)serd_writer_set_prefix;
+	writer->iface.statement = (SerdStatementSink)serd_writer_write_statement;
+	writer->iface.end       = (SerdEndSink)serd_writer_end_anon;
+
 	return writer;
 }
 
@@ -921,7 +932,6 @@ serd_writer_chop_blank_prefix(SerdWriter* writer,
 	}
 }
 
-SERD_API
 SerdStatus
 serd_writer_set_base_uri(SerdWriter*     writer,
                          const SerdNode* uri)
@@ -961,7 +971,6 @@ serd_writer_set_root_uri(SerdWriter*     writer,
 	return SERD_SUCCESS;
 }
 
-SERD_API
 SerdStatus
 serd_writer_set_prefix(SerdWriter*     writer,
                        const SerdNode* name,
@@ -998,6 +1007,13 @@ serd_writer_free(SerdWriter* writer)
 }
 
 SERD_API
+const SerdSinkInterface*
+serd_writer_get_sink_interface(SerdWriter* writer)
+{
+	return &writer->iface;
+}
+
+SERD_API
 SerdEnv*
 serd_writer_get_env(SerdWriter* writer)
 {
diff --git a/tests/read_chunk_test.c b/tests/read_chunk_test.c
index aadbe2c8..ed648e5f 100644
--- a/tests/read_chunk_test.c
+++ b/tests/read_chunk_test.c
@@ -59,13 +59,8 @@ on_end(void* handle, const SerdNode* node)
 int
 main(int argc, char** argv)
 {
-	SerdReader* reader = serd_reader_new(SERD_TURTLE,
-	                                     NULL,
-	                                     NULL,
-	                                     on_base,
-	                                     on_prefix,
-	                                     on_statement,
-	                                     on_end);
+	SerdSinkInterface sink   = { 0, on_base, on_prefix, on_statement, on_end };
+	SerdReader*       reader = serd_reader_new(SERD_TURTLE, &sink);
 	if (!reader) {
 		FAIL("Failed to create reader\n");
 	}
diff --git a/tests/serd_test.c b/tests/serd_test.c
index b96de49f..9fd52852 100644
--- a/tests/serd_test.c
+++ b/tests/serd_test.c
@@ -504,12 +504,13 @@ main(void)
 	serd_writer_chop_blank_prefix(writer, "tmp");
 	serd_writer_chop_blank_prefix(writer, NULL);
 
-	if (!serd_writer_set_base_uri(writer, lit)) {
+	const SerdSinkInterface* iface = serd_writer_get_sink_interface(writer);
+	if (!iface->base(iface->handle, lit)) {
 		FAILF("Set base URI to %s\n", serd_node_get_string(lit));
-	} else if (!serd_writer_set_prefix(writer, lit, lit)) {
+	} else if (!iface->prefix(iface->handle, lit, lit)) {
 		FAILF("Set prefix %s to %s\n",
 		      serd_node_get_string(lit), serd_node_get_string(lit));
-	} else if (!serd_writer_end_anon(writer, NULL)) {
+	} else if (!iface->end(iface->handle, NULL)) {
 		FAIL("Ended non-existent anonymous node\n");
 	} else if (serd_writer_get_env(writer) != env) {
 		FAIL("Writer has incorrect env\n");
@@ -532,8 +533,8 @@ main(void)
 	                              { s,    p,    NULL },
 	                              { NULL, NULL, NULL } };
 	for (unsigned i = 0; i < sizeof(junk) / (sizeof(SerdNode*) * 5); ++i) {
-		if (!serd_writer_write_statement(
-			    writer, 0, NULL,
+		if (!iface->statement(
+			    iface->handle, 0, NULL,
 			    junk[i][0], junk[i][1], junk[i][2])) {
 			FAILF("Successfully wrote junk statement %d\n", i);
 		}
@@ -552,8 +553,8 @@ main(void)
 	                              { s, p, o },
 	                              { s, p, o } };
 	for (unsigned i = 0; i < sizeof(good) / (sizeof(SerdNode*) * 5); ++i) {
-		if (serd_writer_write_statement(
-			    writer, 0, NULL, good[i][0], good[i][1], good[i][2])) {
+		if (iface->statement(
+			    iface->handle, 0, NULL, good[i][0], good[i][1], good[i][2])) {
 			FAILF("Failed to write good statement %d\n", i);
 		}
 	}
@@ -562,11 +563,9 @@ main(void)
 	const char bad_str[] = { (char)0xFF, (char)0x90, 'h', 'i', 0 };
 	SerdNode*  bad_lit   = serd_node_new_string(SERD_LITERAL, bad_str);
 	SerdNode*  bad_uri   = serd_node_new_string(SERD_URI, bad_str);
-	if (serd_writer_write_statement(writer, 0, NULL,
-	                                s, p, bad_lit)) {
+	if (iface->statement(iface->handle, 0, NULL, s, p, bad_lit)) {
 		FAIL("Failed to write junk UTF-8 literal\n");
-	} else if (serd_writer_write_statement(writer, 0, NULL,
-	                                       s, p, bad_uri)) {
+	} else if (iface->statement(iface->handle, 0, NULL, s, p, bad_uri)) {
 		FAIL("Failed to write junk UTF-8 URI\n");
 	}
 	serd_node_free(bad_uri);
@@ -575,8 +574,7 @@ main(void)
 	// Write 1 valid statement
 	serd_node_free(o);
 	o = serd_node_new_string(SERD_LITERAL, "hello");
-	if (serd_writer_write_statement(writer, 0, NULL,
-	                                s, p, o)) {
+	if (iface->statement(iface->handle, 0, NULL, s, p, o)) {
 		FAIL("Failed to write valid statement\n");
 	}
 
@@ -611,16 +609,12 @@ main(void)
 	// Rewind and test reader
 	fseek(fd, 0, SEEK_SET);
 
-	ReaderTest* rt     = (ReaderTest*)calloc(1, sizeof(ReaderTest));
-	SerdReader* reader = serd_reader_new(
-		SERD_TURTLE, rt, free,
-		NULL, NULL, test_sink, NULL);
+	ReaderTest*       rt     = (ReaderTest*)calloc(1, sizeof(ReaderTest));
+	SerdSinkInterface sink   = { rt, NULL, NULL, test_sink, NULL };
+	SerdReader*       reader = serd_reader_new(SERD_TURTLE, &sink);
 	if (!reader) {
 		FAIL("Failed to create reader\n");
 	}
-	if (serd_reader_get_handle(reader) != rt) {
-		FAIL("Corrupt reader handle\n");
-	}
 
 	SerdNode* g = serd_node_new_string(SERD_URI, "http://example.org/");
 	serd_reader_set_default_graph(reader, g);