/* Copyright 2011-2020 David Robillard 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 "env.h" #include "node.h" #include "sink.h" #include "stack.h" #include "string_utils.h" #include "system.h" #include "uri_utils.h" #include "world.h" #include "serd/serd.h" #include #include #include #include #include #include typedef enum { CTX_NAMED, ///< Normal non-anonymous context CTX_BLANK, ///< Anonymous blank node CTX_LIST ///< Anonymous list } ContextType; typedef struct { ContextType type; SerdNode* graph; SerdNode* subject; SerdNode* predicate; bool indented_object; } WriteContext; static const WriteContext WRITE_CONTEXT_NULL = {CTX_NAMED, NULL, NULL, NULL, false}; typedef enum { SEP_NONE, ///< Placeholder for nodes or nothing SEP_END_S, ///< End of a subject ('.') SEP_END_P, ///< End of a predicate (';') SEP_END_O, ///< End of an object (',') SEP_S_P, ///< Between a subject and predicate (whitespace) SEP_P_O, ///< Between a predicate and object (whitespace) SEP_ANON_BEGIN, ///< Start of anonymous node ('[') SEP_ANON_S_P, ///< Between start of anonymous node and predicate SEP_ANON_END, ///< End of anonymous node (']') SEP_LIST_BEGIN, ///< Start of list ('(') SEP_LIST_SEP, ///< List separator (whitespace) SEP_LIST_END, ///< End of list (')') SEP_GRAPH_BEGIN, ///< Start of graph ('{') SEP_GRAPH_END, ///< End of graph ('}') } Sep; typedef uint32_t SepMask; ///< Bitfield of separator flags #define SEP_ALL ((SepMask)-1) #define M(s) (1U << (s)) typedef struct { const char* str; ///< Sep string size_t len; ///< Length of sep string int indent; ///< Indent delta SepMask pre_space_after; ///< Leading space if after given seps SepMask pre_line_after; ///< Leading newline if after given seps SepMask post_line_after; ///< Trailing newline if after given seps } SepRule; static const SepRule rules[] = { {"", 0, +0, SEP_NONE, SEP_NONE, SEP_NONE}, {".\n", 2, -1, SEP_ALL, SEP_NONE, SEP_NONE}, {";", 1, +0, SEP_ALL, SEP_NONE, SEP_ALL}, {",", 1, +0, SEP_ALL, SEP_NONE, ~(M(SEP_ANON_END) | M(SEP_LIST_END))}, {"", 0, +1, SEP_NONE, SEP_NONE, SEP_ALL}, {" ", 1, +0, SEP_NONE, SEP_NONE, SEP_NONE}, {"[", 1, +1, M(SEP_END_O), SEP_NONE, SEP_NONE}, {"", 0, +0, SEP_NONE, SEP_ALL, SEP_NONE}, {"]", 1, -1, SEP_NONE, ~M(SEP_ANON_BEGIN), SEP_NONE}, {"(", 1, +1, M(SEP_END_O), SEP_NONE, SEP_ALL}, {"", 0, +0, SEP_NONE, SEP_ALL, SEP_NONE}, {")", 1, -1, SEP_NONE, SEP_ALL, SEP_NONE}, {"{", 1, +1, SEP_ALL, SEP_NONE, SEP_NONE}, {"}", 1, -1, SEP_NONE, SEP_NONE, SEP_ALL}, {"<", 1, +0, SEP_NONE, SEP_NONE, SEP_NONE}, {">", 1, +0, SEP_NONE, SEP_NONE, SEP_NONE}, }; struct SerdWriterImpl { SerdWorld* world; SerdSink iface; SerdSyntax syntax; SerdStyle style; SerdEnv* env; SerdNode* root_node; SerdURI root_uri; SerdStack anon_stack; SerdWriteFunc write_func; void* stream; SerdErrorSink error_sink; void* error_handle; WriteContext context; unsigned indent; char* bprefix; size_t bprefix_len; Sep last_sep; bool empty; }; typedef enum { WRITE_STRING, 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, SerdField field, SerdStatementFlags flags); static bool supports_abbrev(const SerdWriter* writer) { return writer->syntax == SERD_TURTLE || writer->syntax == SERD_TRIG; } static SerdStatus free_context(SerdWriter* writer) { serd_node_free(writer->context.graph); serd_node_free(writer->context.subject); serd_node_free(writer->context.predicate); return SERD_SUCCESS; } static inline void push_context(SerdWriter* writer, const WriteContext new_context) { WriteContext* top = (WriteContext*)serd_stack_push(&writer->anon_stack, sizeof(WriteContext)); *top = writer->context; writer->context = new_context; } static inline void pop_context(SerdWriter* writer) { assert(!serd_stack_is_empty(&writer->anon_stack)); if (writer->context.indented_object && writer->indent > 0) { --writer->indent; } free_context(writer); writer->context = *(WriteContext*)(writer->anon_stack.buf + writer->anon_stack.size - sizeof(WriteContext)); serd_stack_pop(&writer->anon_stack, sizeof(WriteContext)); } static inline SerdNode* ctx(SerdWriter* writer, const SerdField field) { SerdNode* node = NULL; if (field == SERD_SUBJECT) { node = writer->context.subject; } else if (field == SERD_PREDICATE) { node = writer->context.predicate; } else if (field == SERD_GRAPH) { node = writer->context.graph; } return node && node->type ? node : NULL; } static inline size_t sink(const void* buf, size_t len, SerdWriter* writer) { return writer->write_func(buf, 1, len, writer->stream); } // Write a single character, as an escape for single byte characters // (Caller prints any single byte characters that don't need escaping) static size_t write_character(SerdWriter* writer, const uint8_t* utf8, size_t* size) { char escape[11] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; const uint32_t c = parse_utf8_char(utf8, size); switch (*size) { case 0: serd_world_errorf( writer->world, SERD_ERR_BAD_ARG, "invalid UTF-8: %X\n", utf8[0]); return sink(replacement_char, sizeof(replacement_char), writer); case 1: snprintf(escape, sizeof(escape), "\\u%04X", utf8[0]); return sink(escape, 6, writer); default: break; } if (!(writer->style & SERD_STYLE_ASCII)) { // Write UTF-8 character directly to UTF-8 output return sink(utf8, *size, writer); } if (c <= 0xFFFF) { snprintf(escape, sizeof(escape), "\\u%04X", c); return sink(escape, 6, writer); } else { snprintf(escape, sizeof(escape), "\\U%08X", c); return sink(escape, 10, writer); } } static inline bool uri_must_escape(const char c) { switch (c) { case ' ': case '"': case '<': case '>': case '\\': case '^': case '`': case '{': case '|': case '}': return true; default: return !in_range(c, 0x20, 0x7E); } } static size_t write_uri(SerdWriter* writer, const char* utf8, size_t n_bytes) { size_t len = 0; for (size_t i = 0; i < n_bytes;) { size_t j = i; // Index of next character that must be escaped for (; j < n_bytes; ++j) { if (uri_must_escape(utf8[j])) { break; } } // Bulk write all characters up to this special one len += sink(&utf8[i], j - i, writer); if ((i = j) == n_bytes) { break; // Reached end } // Write UTF-8 character size_t size = 0; len += write_character(writer, (const uint8_t*)utf8 + i, &size); i += size; if (size == 0) { // Corrupt input, scan to start of next character for (++i; i < n_bytes && (utf8[i] & 0x80); ++i) {} } } return len; } static size_t write_uri_from_node(SerdWriter* writer, const SerdNode* node) { return write_uri(writer, serd_node_get_string(node), node->n_bytes); } static bool lname_must_escape(const char c) { /* This arbitrary list of characters, most of which have nothing to do with Turtle, must be handled as special cases here because the RDF and SPARQL WGs are apparently intent on making the once elegant Turtle a baroque and inconsistent mess, throwing elegance and extensibility completely out the window for no good reason. Note '-', '.', and '_' are also in PN_LOCAL_ESC, but are valid unescaped in local names, so they are not escaped here. */ switch (c) { case '\'': case '!': case '#': case '$': case '%': case '&': case '(': case ')': case '*': case '+': case ',': case '/': case ';': case '=': case '?': case '@': case '~': return true; default: break; } return false; } static size_t write_lname(SerdWriter* writer, const char* utf8, size_t n_bytes) { size_t len = 0; for (size_t i = 0; i < n_bytes; ++i) { size_t j = i; // Index of next character that must be escaped for (; j < n_bytes; ++j) { if (lname_must_escape(utf8[j])) { break; } } // Bulk write all characters up to this special one len += sink(&utf8[i], j - i, writer); if ((i = j) == n_bytes) { break; // Reached end } // Write escape len += sink("\\", 1, writer); len += sink(&utf8[i], 1, writer); } return len; } static size_t write_text(SerdWriter* writer, TextContext ctx, const char* utf8, size_t n_bytes) { size_t len = 0; for (size_t i = 0; i < n_bytes;) { // Fast bulk write for long strings of printable ASCII size_t j = i; for (; j < n_bytes; ++j) { if (utf8[j] == '\\' || utf8[j] == '"' || (!in_range(utf8[j], 0x20, 0x7E))) { break; } } len += sink(&utf8[i], j - i, writer); if ((i = j) == n_bytes) { break; // Reached end } const uint8_t in = utf8[i++]; if (ctx == WRITE_LONG_STRING) { switch (in) { case '\\': len += sink("\\\\", 2, writer); continue; case '\b': len += sink("\\b", 2, writer); continue; case '\n': case '\r': case '\t': case '\f': len += sink(&in, 1, writer); // Write character as-is continue; case '\"': if (i == n_bytes) { // '"' at string end len += sink("\\\"", 2, writer); } else { len += sink(&in, 1, writer); } continue; default: break; } } else if (ctx == WRITE_STRING) { switch (in) { case '\\': len += sink("\\\\", 2, writer); continue; case '\n': len += sink("\\n", 2, writer); continue; case '\r': len += sink("\\r", 2, writer); continue; case '\t': len += sink("\\t", 2, writer); continue; case '"': len += sink("\\\"", 2, writer); continue; default: break; } if (writer->syntax == SERD_TURTLE) { switch (in) { case '\b': len += sink("\\b", 2, writer); continue; case '\f': len += sink("\\f", 2, writer); continue; default: break; } } } // Write UTF-8 character size_t size = 0; len += write_character(writer, (const uint8_t*)utf8 + i - 1, &size); if (size == 0) { // Corrupt input, scan to start of next character for (; i < n_bytes && (utf8[i] & 0x80); ++i) {} } else { i += size - 1; } } return len; } static size_t uri_sink(const void* buf, size_t size, size_t nmemb, void* stream) { (void)size; assert(size == 1); return write_uri((SerdWriter*)stream, (const char*)buf, nmemb); } static void write_newline(SerdWriter* writer) { sink("\n", 1, writer); for (unsigned i = 0; i < writer->indent; ++i) { sink("\t", 1, writer); } } static bool write_sep(SerdWriter* writer, const Sep sep) { const SepRule* rule = &rules[sep]; // Adjust indent, but tolerate if it would become negative writer->indent = ((rule->indent >= 0 || writer->indent >= (unsigned)-rule->indent) ? writer->indent + rule->indent : 0); // Write newline or space before separator if necessary if (rule->pre_line_after & (1u << writer->last_sep)) { write_newline(writer); } else if (rule->pre_space_after & (1u << writer->last_sep)) { sink(" ", 1, writer); } // Write actual separator string sink(rule->str, rule->len, writer); // Write newline after separator if necessary if (rule->post_line_after & (1u << writer->last_sep)) { write_newline(writer); writer->last_sep = SEP_NONE; } else { writer->last_sep = sep; } if (sep == SEP_END_S) { writer->indent = 0; } return true; } static SerdStatus reset_context(SerdWriter* writer, bool graph) { if (graph && writer->context.graph) { memset(writer->context.graph, 0, sizeof(SerdNode)); } if (writer->context.subject) { memset(writer->context.subject, 0, sizeof(SerdNode)); } if (writer->context.predicate) { memset(writer->context.predicate, 0, sizeof(SerdNode)); } writer->context.indented_object = false; writer->empty = false; return SERD_SUCCESS; } static bool is_inline_start(const SerdWriter* writer, SerdField field, SerdStatementFlags flags) { return (supports_abbrev(writer) && ((field == SERD_SUBJECT && (flags & SERD_ANON_S_BEGIN)) || (field == SERD_OBJECT && (flags & SERD_ANON_O_BEGIN)))); } static bool write_literal(SerdWriter* writer, const SerdNode* node, SerdStatementFlags flags) { writer->last_sep = SEP_NONE; const SerdNode* datatype = serd_node_get_datatype(node); const SerdNode* lang = serd_node_get_language(node); const char* node_str = serd_node_get_string(node); const char* type_uri = serd_node_get_string(datatype); if (supports_abbrev(writer) && type_uri) { if (serd_node_equals(datatype, writer->world->xsd_boolean) || serd_node_equals(datatype, writer->world->xsd_integer)) { sink(node_str, node->n_bytes, writer); return true; } else if (serd_node_equals(datatype, writer->world->xsd_decimal) && strchr(node_str, '.') && node_str[node->n_bytes - 1] != '.') { /* xsd:decimal literals without trailing digits, e.g. "5.", can not be written bare in Turtle. We could add a 0 which is prettier, but changes the text and breaks round tripping. */ sink(node_str, node->n_bytes, writer); return true; } } if (supports_abbrev(writer) && (node->flags & (SERD_HAS_NEWLINE|SERD_HAS_QUOTE))) { sink("\"\"\"", 3, writer); write_text(writer, WRITE_LONG_STRING, node_str, node->n_bytes); sink("\"\"\"", 3, writer); } else { sink("\"", 1, writer); write_text(writer, WRITE_STRING, node_str, node->n_bytes); sink("\"", 1, writer); } if (lang && serd_node_get_string(lang)) { sink("@", 1, writer); sink(serd_node_get_string(lang), lang->n_bytes, writer); } else if (type_uri) { sink("^^", 2, writer); return write_node(writer, datatype, (SerdField)-1, flags); } return true; } // Return true iff `buf` is a valid prefixed name prefix or suffix static inline bool is_name(const char* buf, const size_t len) { // TODO: This is more strict than it should be. for (size_t i = 0; i < len; ++i) { if (!(is_alpha(buf[i]) || is_digit(buf[i]))) { return false; } } return true; } static bool write_uri_node(SerdWriter* const writer, const SerdNode* node, const SerdField field, const SerdStatementFlags flags) { if (is_inline_start(writer, field, flags)) { write_sep(writer, SEP_ANON_BEGIN); sink(" == ", 4, writer); } writer->last_sep = SEP_NONE; const SerdNode* prefix = NULL; SerdStringView suffix = {NULL, 0}; const char* node_str = serd_node_get_string(node); const bool has_scheme = serd_uri_string_has_scheme(node_str); if (field == SERD_PREDICATE && supports_abbrev(writer) && serd_node_equals(node, writer->world->rdf_type)) { return sink("a", 1, writer) == 1; } else if (supports_abbrev(writer) && serd_node_equals(node, writer->world->rdf_nil)) { return sink("()", 2, writer) == 2; } else if (has_scheme && supports_abbrev(writer) && serd_env_qualify_in_place(writer->env, node, &prefix, &suffix) && is_name(serd_node_get_string(prefix), serd_node_get_length(prefix)) && is_name(suffix.buf, suffix.len)) { write_uri_from_node(writer, prefix); sink(":", 1, writer); write_uri(writer, suffix.buf, suffix.len); return true; } sink("<", 1, writer); if (serd_env_get_base_uri(writer->env)) { const SerdURI* base_uri = serd_env_get_parsed_base_uri(writer->env); SerdURI uri; SerdURI abs_uri; serd_uri_parse(node_str, &uri); serd_uri_resolve(&uri, base_uri, &abs_uri); bool rooted = uri_is_under(base_uri, &writer->root_uri); const SerdURI* root = rooted ? &writer->root_uri : base_uri; if (!uri_is_under(&abs_uri, root) || writer->syntax == SERD_NTRIPLES || writer->syntax == SERD_NQUADS) { serd_uri_serialise(&abs_uri, uri_sink, writer); } else { serd_uri_serialise_relative(&uri, base_uri, root, uri_sink, writer); } } else { write_uri_from_node(writer, node); } sink(">", 1, writer); if (is_inline_start(writer, field, flags)) { sink(" ;", 2, writer); } return true; } static bool write_curie(SerdWriter* const writer, const SerdNode* node, const SerdField field, const SerdStatementFlags flags) { writer->last_sep = SEP_NONE; SerdStringView prefix = {NULL, 0}; SerdStringView suffix = {NULL, 0}; SerdStatus st = SERD_SUCCESS; switch (writer->syntax) { case SERD_NTRIPLES: case SERD_NQUADS: if ((st = serd_env_expand_in_place( writer->env, node, &prefix, &suffix))) { serd_world_errorf(writer->world, st, "undefined namespace prefix `%s'\n", serd_node_get_string(node)); return false; } sink("<", 1, writer); write_uri(writer, prefix.buf, prefix.len); write_uri(writer, suffix.buf, suffix.len); sink(">", 1, writer); break; case SERD_TURTLE: case SERD_TRIG: if (is_inline_start(writer, field, flags)) { write_sep(writer, SEP_ANON_BEGIN); sink(" == ", 4, writer); } write_lname(writer, serd_node_get_string(node), node->n_bytes); if (is_inline_start(writer, field, flags)) { sink(" ;", 2, writer); } } return true; } static bool write_blank(SerdWriter* const writer, const SerdNode* node, const SerdField field, const SerdStatementFlags flags) { const char* node_str = serd_node_get_string(node); if (supports_abbrev(writer)) { if (is_inline_start(writer, field, flags)) { return write_sep(writer, SEP_ANON_BEGIN); } else if ((field == SERD_SUBJECT && (flags & SERD_LIST_S_BEGIN)) || (field == SERD_OBJECT && (flags & SERD_LIST_O_BEGIN))) { return write_sep(writer, SEP_LIST_BEGIN); } else if (field == SERD_SUBJECT && (flags & SERD_EMPTY_S)) { writer->last_sep = SEP_NONE; // Treat "[]" like anode return sink("[]", 2, writer) == 2; } } sink("_:", 2, writer); if (writer->bprefix && !strncmp(node_str, writer->bprefix, writer->bprefix_len)) { sink(node_str + writer->bprefix_len, node->n_bytes - writer->bprefix_len, writer); } else { sink(node_str, node->n_bytes, writer); } writer->last_sep = SEP_NONE; return true; } static bool write_node(SerdWriter* writer, const SerdNode* node, const SerdField field, SerdStatementFlags flags) { switch (node->type) { case SERD_LITERAL: return write_literal(writer, node, flags); case SERD_URI: return write_uri_node(writer, node, field, flags); case SERD_CURIE: return write_curie(writer, node, field, flags); case SERD_BLANK: return write_blank(writer, node, field, flags); } return false; } static inline bool is_resource(const SerdNode* node) { return node->type > SERD_LITERAL; } static void write_pred(SerdWriter* writer, SerdStatementFlags flags, const SerdNode* pred) { write_node(writer, pred, SERD_PREDICATE, flags); write_sep(writer, SEP_P_O); serd_node_set(&writer->context.predicate, pred); } static bool write_list_obj(SerdWriter* writer, SerdStatementFlags flags, const SerdNode* predicate, const SerdNode* object) { if (serd_node_equals(object, writer->world->rdf_nil)) { write_sep(writer, SEP_LIST_END); return true; } if (serd_node_equals(predicate, writer->world->rdf_first)) { write_node(writer, object, SERD_OBJECT, flags); } else { write_sep(writer, SEP_LIST_SEP); } return false; } static SerdStatus serd_writer_write_statement(SerdWriter* writer, SerdStatementFlags flags, const SerdStatement* statement) { assert(!((flags & SERD_EMPTY_S) && (flags & SERD_ANON_S_BEGIN))); assert(!((flags & SERD_EMPTY_S) && (flags & SERD_LIST_S_BEGIN))); assert(!((flags & SERD_ANON_S_BEGIN) && (flags & SERD_LIST_S_BEGIN))); assert(!((flags & SERD_ANON_O_BEGIN) && (flags & SERD_LIST_O_BEGIN))); const SerdNode* const subject = serd_statement_get_subject(statement); const SerdNode* const predicate = serd_statement_get_predicate(statement); const SerdNode* const object = serd_statement_get_object(statement); const SerdNode* const graph = serd_statement_get_graph(statement); if (!subject || !predicate || !object || !is_resource(subject) || !is_resource(predicate)) { return SERD_ERR_BAD_ARG; } #define TRY(write_result) \ if (!(write_result)) { \ return SERD_ERR_UNKNOWN; \ } switch (writer->syntax) { case SERD_NTRIPLES: case SERD_NQUADS: TRY(write_node(writer, subject, SERD_SUBJECT, flags)); sink(" ", 1, writer); TRY(write_node(writer, predicate, SERD_PREDICATE, flags)); sink(" ", 1, writer); TRY(write_node(writer, object, SERD_OBJECT, flags)); if (writer->syntax == SERD_NQUADS && graph) { sink(" ", 1, writer); TRY(write_node(writer, graph, SERD_GRAPH, flags)); } sink(" .\n", 3, writer); return SERD_SUCCESS; default: break; } if ((graph && !serd_node_equals(graph, writer->context.graph)) || (!graph && ctx(writer, SERD_GRAPH))) { if (ctx(writer, SERD_SUBJECT)) { write_sep(writer, SEP_END_S); } if (ctx(writer, SERD_GRAPH)) { write_sep(writer, SEP_GRAPH_END); } if (!writer->empty) { write_newline(writer); // Blank line between top level items } reset_context(writer, true); if (graph) { TRY(write_node(writer, graph, SERD_GRAPH, flags)); write_sep(writer, SEP_GRAPH_BEGIN); serd_node_set(&writer->context.graph, graph); } } if (writer->context.type == CTX_LIST) { if (write_list_obj(writer, flags, predicate, object)) { // Reached end of list pop_context(writer); return SERD_SUCCESS; } } else if (serd_node_equals(subject, writer->context.subject)) { if (serd_node_equals(predicate, writer->context.predicate)) { // Abbreviate S P if (!writer->context.indented_object && !(flags & (SERD_ANON_O_BEGIN | SERD_LIST_O_BEGIN))) { ++writer->indent; writer->context.indented_object = true; } write_sep(writer, SEP_END_O); write_node(writer, object, SERD_OBJECT, flags); } else { // Abbreviate S if (writer->context.indented_object && writer->indent > 0) { --writer->indent; writer->context.indented_object = false; } Sep sep = ctx(writer, SERD_PREDICATE) ? SEP_END_P : SEP_S_P; write_sep(writer, sep); write_pred(writer, flags, predicate); write_node(writer, object, SERD_OBJECT, flags); } } else { // No abbreviation if (writer->context.indented_object && writer->indent > 0) { --writer->indent; writer->context.indented_object = false; } if (serd_stack_is_empty(&writer->anon_stack)) { if (ctx(writer, SERD_SUBJECT)) { write_sep(writer, SEP_END_S); // Terminate last subject } if (!writer->empty) { write_newline(writer); // Blank line between top level items } } if (serd_stack_is_empty(&writer->anon_stack)) { write_node(writer, subject, SERD_SUBJECT, flags); if (!(flags & (SERD_ANON_S_BEGIN | SERD_LIST_S_BEGIN))) { write_sep(writer, SEP_S_P); } else if (flags & SERD_ANON_S_BEGIN) { write_sep(writer, SEP_ANON_S_P); } } else { write_sep(writer, SEP_ANON_S_P); } reset_context(writer, false); serd_node_set(&writer->context.subject, subject); if (!(flags & SERD_LIST_S_BEGIN)) { write_pred(writer, flags, predicate); } write_node(writer, object, SERD_OBJECT, flags); } if (flags & SERD_LIST_S_BEGIN) { const WriteContext ctx = {CTX_LIST, serd_node_copy(graph), serd_node_copy(subject), NULL, false}; push_context(writer, ctx); } if (flags & SERD_LIST_O_BEGIN) { const WriteContext ctx = {CTX_LIST, serd_node_copy(graph), serd_node_copy(object), NULL, false}; push_context(writer, ctx); } if (flags & (SERD_ANON_S_BEGIN | SERD_ANON_O_BEGIN)) { const bool is_list = flags & (SERD_LIST_S_BEGIN | SERD_LIST_O_BEGIN); const bool is_subject = flags & SERD_ANON_S_BEGIN; const WriteContext ctx = {is_list ? CTX_LIST : CTX_BLANK, serd_node_copy(graph), serd_node_copy(subject), is_subject ? serd_node_copy(predicate) : NULL, false}; push_context(writer, ctx); } else { serd_node_set(&writer->context.graph, graph); serd_node_set(&writer->context.subject, subject); serd_node_set(&writer->context.predicate, predicate); } return SERD_SUCCESS; } static SerdStatus serd_writer_end_anon(SerdWriter* writer, const SerdNode* node) { if (writer->syntax == SERD_NTRIPLES || writer->syntax == SERD_NQUADS) { return SERD_SUCCESS; } else if (serd_stack_is_empty(&writer->anon_stack)) { return serd_world_errorf(writer->world, SERD_ERR_UNKNOWN, "unexpected end of anonymous node\n"); } write_sep(writer, SEP_ANON_END); pop_context(writer); if (serd_node_equals(node, writer->context.subject)) { // Now-finished anonymous node is the new subject with no other context memset(writer->context.predicate, 0, sizeof(SerdNode)); } return SERD_SUCCESS; } SerdStatus serd_writer_finish(SerdWriter* writer) { if (ctx(writer, SERD_SUBJECT)) { write_sep(writer, SEP_END_S); } if (ctx(writer, SERD_GRAPH)) { write_sep(writer, SEP_GRAPH_END); } free_context(writer); writer->indent = 0; writer->context = WRITE_CONTEXT_NULL; return SERD_SUCCESS; } SerdWriter* serd_writer_new(SerdWorld* world, SerdSyntax syntax, SerdStyleFlags style, SerdEnv* env, SerdWriteFunc write_func, void* stream) { const WriteContext context = WRITE_CONTEXT_NULL; SerdWriter* writer = (SerdWriter*)calloc(1, sizeof(SerdWriter)); writer->world = world; writer->syntax = syntax; writer->style = style; writer->env = env; writer->root_node = NULL; writer->root_uri = SERD_URI_NULL; writer->anon_stack = serd_stack_new(SERD_PAGE_SIZE); writer->write_func = write_func; writer->stream = stream; writer->context = context; writer->empty = true; 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; } void serd_writer_chop_blank_prefix(SerdWriter* writer, const char* prefix) { free(writer->bprefix); writer->bprefix_len = 0; writer->bprefix = NULL; if (prefix) { writer->bprefix_len = strlen(prefix); writer->bprefix = (char*)malloc(writer->bprefix_len + 1); memcpy(writer->bprefix, prefix, writer->bprefix_len + 1); } } SerdStatus serd_writer_set_base_uri(SerdWriter* writer, const SerdNode* uri) { if (!serd_env_set_base_uri(writer->env, uri)) { if (writer->syntax == SERD_TURTLE || writer->syntax == SERD_TRIG) { if (ctx(writer, SERD_GRAPH) || ctx(writer, SERD_SUBJECT)) { sink(" .\n\n", 4, writer); reset_context(writer, true); } sink("@base <", 7, writer); sink(serd_node_get_string(uri), uri->n_bytes, writer); sink("> .\n", 4, writer); } writer->indent = 0; return reset_context(writer, true); } return SERD_ERR_UNKNOWN; } SerdStatus serd_writer_set_root_uri(SerdWriter* writer, const SerdNode* uri) { serd_node_free(writer->root_node); if (uri) { writer->root_node = serd_node_copy(uri); serd_uri_parse(serd_node_get_string(writer->root_node), &writer->root_uri); } else { writer->root_node = NULL; writer->root_uri = SERD_URI_NULL; } return SERD_SUCCESS; } SerdStatus serd_writer_set_prefix(SerdWriter* writer, const SerdNode* name, const SerdNode* uri) { if (!serd_env_set_prefix(writer->env, name, uri)) { if (writer->syntax == SERD_TURTLE || writer->syntax == SERD_TRIG) { if (ctx(writer, SERD_GRAPH) || ctx(writer, SERD_SUBJECT)) { sink(" .\n\n", 4, writer); reset_context(writer, true); } sink("@prefix ", 8, writer); sink(serd_node_get_string(name), name->n_bytes, writer); sink(": <", 3, writer); write_uri_from_node(writer, uri); sink("> .\n", 4, writer); } writer->indent = 0; return reset_context(writer, true); } return SERD_ERR_UNKNOWN; } void serd_writer_free(SerdWriter* writer) { serd_writer_finish(writer); serd_stack_free(&writer->anon_stack); free(writer->bprefix); serd_node_free(writer->root_node); free(writer); } const SerdSink* serd_writer_get_sink(SerdWriter* writer) { return &writer->iface; } SerdEnv* serd_writer_get_env(SerdWriter* writer) { return writer->env; } size_t serd_buffer_sink(const void* buf, size_t size, size_t nmemb, void* stream) { assert(size == 1); (void)size; SerdBuffer* buffer = (SerdBuffer*)stream; buffer->buf = (char*)realloc(buffer->buf, buffer->len + nmemb); memcpy((uint8_t*)buffer->buf + buffer->len, buf, nmemb); buffer->len += nmemb; return nmemb; } char* serd_buffer_sink_finish(SerdBuffer* stream) { serd_buffer_sink("", 1, 1, stream); return (char*)stream->buf; }