Add serd_node_from_syntax() and serd_node_to_syntax()

3 files changed, 150 insertions, 0 deletions

diff --git a/src/node_syntax.c b/src/node_syntax.c
new file mode 100644
index 00000000..626648f6
--- /dev/null
+++ b/src/node_syntax.c
@@ -0,0 +1,122 @@
+/*
+  Copyright 2011-2020 David Robillard <d@drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include "writer.h"
+
+#include "serd/serd.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static SerdStatus
+on_node_string_event(void* const handle, const SerdEvent* const event)
+{
+  if (event->type == SERD_STATEMENT) {
+    *(SerdNode**)handle =
+      serd_node_copy(serd_statement_object(event->statement.statement));
+  }
+
+  return SERD_SUCCESS;
+}
+
+static SerdNode*
+serd_node_from_syntax_in(const char* const str,
+                         const SerdSyntax  syntax,
+                         SerdEnv* const    env)
+{
+  static const char* const prelude =
+    "_:s <http://www.w3.org/2000/01/rdf-schema#object>";
+
+  const size_t str_len = strlen(str);
+  const size_t doc_len = strlen(prelude) + str_len + 4;
+  char* const  doc     = (char*)calloc(doc_len + 1, 1);
+
+  snprintf(doc, doc_len + 1, "%s %s .", prelude, str);
+
+  SerdNode*        object = NULL;
+  SerdWorld* const world  = serd_world_new();
+  SerdSink* const  sink   = serd_sink_new(&object, on_node_string_event, NULL);
+
+  SerdByteSource* const source = serd_byte_source_new_string(doc, NULL);
+  SerdReader* const     reader = serd_reader_new(
+    world, syntax, SERD_READ_EXACT_BLANKS, env, sink, 1024 + doc_len);
+
+  serd_reader_start(reader, source);
+  serd_reader_read_document(reader);
+  serd_reader_finish(reader);
+  serd_reader_free(reader);
+  serd_byte_source_free(source);
+  serd_sink_free(sink);
+  serd_world_free(world);
+  free(doc);
+
+  return object;
+}
+
+SerdNode*
+serd_node_from_syntax(const char* const str,
+                      const SerdSyntax  syntax,
+                      SerdEnv* const    env)
+{
+  if (env) {
+    return serd_node_from_syntax_in(str, syntax, env);
+  }
+
+  SerdEnv* const  temp_env = serd_env_new(SERD_EMPTY_STRING());
+  SerdNode* const node     = serd_node_from_syntax_in(str, syntax, temp_env);
+
+  serd_env_free(temp_env);
+  return node;
+}
+
+static char*
+serd_node_to_syntax_in(const SerdNode* const node,
+                       const SerdSyntax      syntax,
+                       const SerdEnv* const  env)
+{
+  SerdWorld* const    world  = serd_world_new();
+  SerdBuffer          buffer = {NULL, 0};
+  SerdByteSink* const out    = serd_byte_sink_new_buffer(&buffer);
+  SerdWriter* const   writer = serd_writer_new(world, syntax, 0, env, out);
+
+  char* result = NULL;
+  if (!serd_writer_write_node(writer, node) && !serd_writer_finish(writer)) {
+    result = serd_buffer_sink_finish(&buffer);
+  }
+
+  serd_writer_free(writer);
+  serd_byte_sink_free(out);
+  serd_world_free(world);
+
+  return result;
+}
+
+char*
+serd_node_to_syntax(const SerdNode* const node,
+                    const SerdSyntax      syntax,
+                    const SerdEnv* const  env)
+{
+  if (env) {
+    return serd_node_to_syntax_in(node, syntax, env);
+  }
+
+  SerdEnv* const temp_env = serd_env_new(SERD_EMPTY_STRING());
+  char* const    string   = serd_node_to_syntax_in(node, syntax, temp_env);
+
+  serd_env_free(temp_env);
+  return string;
+}
diff --git a/src/writer.c b/src/writer.c
index bfce4f9e..c6a91d78 100644
--- a/src/writer.c
+++ b/src/writer.c
@@ -14,6 +14,8 @@
   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
 
+#include "writer.h"
+
 #include "byte_sink.h"
 #include "env.h"
 #include "node.h"
@@ -1259,6 +1261,12 @@ serd_writer_on_event(SerdWriter* writer, const SerdEvent* event)
 }
 
 SerdStatus
+serd_writer_write_node(SerdWriter* writer, const SerdNode* node)
+{
+  return write_node(writer, node, SERD_OBJECT, 0);
+}
+
+SerdStatus
 serd_writer_finish(SerdWriter* writer)
 {
   SerdStatus st = SERD_SUCCESS;
diff --git a/src/writer.h b/src/writer.h
new file mode 100644
index 00000000..c80fe49c
--- /dev/null
+++ b/src/writer.h
@@ -0,0 +1,20 @@
+/*
+  Copyright 2019-2020 David Robillard <d@drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include "serd/serd.h"
+
+SerdStatus
+serd_writer_write_node(SerdWriter* writer, const SerdNode* node);