Syntax support via Serd.

Preliminary syntax-using command line program.


git-svn-id: http://svn.drobilla.net/sord/trunk@9 3d64ff67-21c5-427c-a301-fe4f08042e5a

1 files changed, 176 insertions, 0 deletions

diff --git a/src/syntax.c b/src/syntax.c
new file mode 100644
index 0000000..4a58ac9
--- /dev/null
+++ b/src/syntax.c
@@ -0,0 +1,176 @@
+/* Sord, a lightweight RDF model library.
+ * Copyright 2010-2011 David Robillard <d@drobilla.net>
+ *
+ * Sord is free software: you can redistribute it and/or modify it under
+ * the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Sord 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 Lesser General Public
+ * License for details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "serd/serd.h"
+
+#include "sord-config.h"
+#include "sord/sord.h"
+
+typedef struct {
+	SerdReader reader;
+	SerdEnv    env;
+	SerdNode   base_uri_node;
+	SerdURI    base_uri;
+	Sord       sord;
+} ReadState;
+
+static uint8_t*
+copy_string(const uint8_t* str, size_t* n_bytes)
+{
+	const size_t   len = strlen((const char*)str);
+	uint8_t* const ret = malloc(len + 1);
+	memcpy(ret, str, len + 1);
+	*n_bytes = len + 1;
+	return ret;
+}
+
+static bool
+event_base(void*           handle,
+           const SerdNode* uri_node)
+{
+	ReadState* const state         = (ReadState*)handle;
+	SerdNode         base_uri_node = *uri_node;
+	SerdURI          base_uri;
+	if (!serd_uri_parse(uri_node->buf, &base_uri)) {
+		return false;
+	}
+
+	SerdURI abs_base_uri;
+	if (!serd_uri_resolve(&base_uri, &state->base_uri, &abs_base_uri)) {
+		fprintf(stderr, "error: failed to resolve new base URI\n");
+		return false;
+	}
+	base_uri_node = serd_node_new_uri(&abs_base_uri, &base_uri);
+
+	serd_node_free(&state->base_uri_node);
+	state->base_uri_node = base_uri_node;
+	state->base_uri      = base_uri;
+	return true;
+}
+
+static bool
+event_prefix(void*           handle,
+             const SerdNode* name,
+             const SerdNode* uri_node)
+{
+	ReadState* const state = (ReadState*)handle;
+	if (!serd_uri_string_has_scheme(uri_node->buf)) {
+		SerdURI uri;
+		if (!serd_uri_parse(uri_node->buf, &uri)) {
+			return false;
+		}
+		SerdURI abs_uri;
+		if (!serd_uri_resolve(&uri, &state->base_uri, &abs_uri)) {
+			return false;
+		}
+		SerdURI  base_uri;
+		SerdNode base_uri_node = serd_node_new_uri(&abs_uri, &base_uri);
+		serd_env_add(state->env, name, &base_uri_node);
+		serd_node_free(&base_uri_node);
+	} else {
+		serd_env_add(state->env, name, uri_node);
+	}
+	return true;
+}
+
+static inline SordID
+sord_node_from_serd_node(ReadState* state, const SerdNode* sn)
+{
+	return sord_get_uri_counted(state->sord, true, (const char*)sn->buf, sn->n_chars);
+}
+
+static bool
+event_statement(void*           handle,
+                const SerdNode* graph,
+                const SerdNode* subject,
+                const SerdNode* predicate,
+                const SerdNode* object,
+                const SerdNode* object_datatype,
+                const SerdNode* object_lang)
+{
+	ReadState* const state = (ReadState*)handle;
+
+	SordTuple tup;
+	tup[0] = sord_node_from_serd_node(state, subject);
+	tup[1] = sord_node_from_serd_node(state, predicate);
+	tup[2] = sord_node_from_serd_node(state, object);
+	tup[3] = (graph && graph->buf)
+		? sord_node_from_serd_node(state, graph)
+		: NULL;
+	
+	sord_add(state->sord, tup);
+
+	return true;
+}
+
+SORD_API
+bool
+sord_read_file(Sord sord, const uint8_t* input)
+{
+	const uint8_t* filename = NULL;
+	if (serd_uri_string_has_scheme(input)) {
+		// INPUT is an absolute URI, ensure it a file and chop scheme
+		if (strncmp((const char*)input, "file:", 5)) {
+			fprintf(stderr, "unsupported URI scheme `%s'\n", input);
+			return 1;
+		} else if (!strncmp((const char*)input, "file://", 7)) {
+			filename = input + 7;
+		} else {
+			filename = input + 5;
+		}
+	} else {
+		filename = input;
+	}
+
+	FILE* in_fd = fopen((const char*)input,  "r");
+	if (!in_fd) {
+		fprintf(stderr, "failed to open file %s\n", input);
+		return 1;
+	}
+
+	size_t   base_uri_n_bytes = 0;
+	uint8_t* base_uri_str     = copy_string(input, &base_uri_n_bytes);
+	SerdURI  base_uri;
+	if (!serd_uri_parse(base_uri_str, &base_uri)) {
+		fprintf(stderr, "invalid base URI `%s'\n", base_uri_str);
+	}
+
+	SerdEnv env = serd_env_new();
+
+	const SerdNode base_uri_node = { SERD_URI,
+	                                 base_uri_n_bytes,
+	                                 base_uri_n_bytes - 1,  // FIXME: UTF-8
+	                                 base_uri_str };
+
+	ReadState state = { NULL, env, base_uri_node, base_uri, sord };
+
+	state.reader = serd_reader_new(
+		SERD_TURTLE, &state,
+		event_base, event_prefix, event_statement, NULL);
+
+	const bool success = serd_reader_read_file(state.reader, in_fd, input);
+
+	serd_reader_free(state.reader);
+	serd_env_free(state.env);
+	serd_node_free(&state.base_uri_node);
+	fclose(in_fd);
+
+	return success;
+}