diff options
Diffstat (limited to 'src/write.c')
| -rw-r--r-- | src/write.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/src/write.c b/src/write.c new file mode 100644 index 00000000..c2b92d78 --- /dev/null +++ b/src/write.c @@ -0,0 +1,170 @@ +/* Serd, an RDF serialisation library. + * Copyright 2011 David Robillard <d@drobilla.net> + * + * Serd 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. + * + * Serd 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 <assert.h> +#include <stdlib.h> + +#include "serd/serd.h" + +static size_t +file_sink(const uint8_t* buf, size_t len, void* stream) +{ + FILE* file = (FILE*)stream; + return fwrite(buf, 1, len, file); +} + +static inline bool +serd_write_uri(FILE* file, const SerdURI* uri) +{ + return serd_uri_serialise(uri, file_sink, file); +} + +static bool +serd_write_ascii(const uint8_t* utf8, size_t n_bytes, FILE* out_fd, const uint8_t esc) +{ + for (size_t i = 0; i < n_bytes;) { + uint8_t in = utf8[i++]; + switch (in) { + case '\\': fwrite("\\\\", 1, 2, out_fd); continue; + case '\n': fwrite("\\n", 1, 2, out_fd); continue; + case '\r': fwrite("\\r", 1, 2, out_fd); continue; + case '\t': fwrite("\\t", 1, 2, out_fd); continue; + case '"': if (esc == '"') { fwrite("\\\"", 1, 2, out_fd); continue; } + default: break; + } + + if (in == esc) { + fprintf(out_fd, "\\u%04X", esc); + continue; + } + + uint32_t c = 0; + size_t size = 0; + if ((in & 0x80) == 0) { // Starts with `0' + size = 1; + c = in & 0x7F; + if ((in >= 0x20) && (in <= 0x7E)) { // Printable ASCII + fwrite(&in, 1, 1, out_fd); + continue; + } + } else if ((in & 0xE0) == 0xC0) { // Starts with `110' + size = 2; + c = in & 0x1F; + } else if ((in & 0xF0) == 0xE0) { // Starts with `1110' + size = 3; + c = in & 0x0F; + } else if ((in & 0xF8) == 0xF0) { // Starts with `11110' + size = 4; + c = in & 0x07; + } else if ((in & 0xFC) == 0xF8) { // Starts with `111110' + size = 5; + c = in & 0x03; + } else if ((in & 0xFE) == 0xFC) { // Starts with `1111110' + size = 6; + c = in & 0x01; + } else { + fprintf(stderr, "invalid UTF-8 at offset %zu: %X\n", i, in); + return false; + } + +#define READ_BYTE() do { \ + assert(i < n_bytes); \ + in = utf8[i++] & 0x3f; \ + c <<= 6; \ + c |= in; \ + } while (0) + + switch (size) { + case 6: READ_BYTE(); + case 5: READ_BYTE(); + case 4: READ_BYTE(); + case 3: READ_BYTE(); + case 2: READ_BYTE(); + } + + if (c < 0xFFFF) { + fprintf(out_fd, "\\u%04X", c); + } else { + fprintf(out_fd, "\\U%08X", c); + } + } + return true; +} + +SERD_API +bool +serd_write_node(FILE* fd, + const SerdURI* base_uri, + SerdNamespaces ns, + SerdNodeType type, + const SerdString* str, + const SerdString* datatype, + const SerdString* lang) +{ + SerdRange uri_prefix; + SerdRange uri_suffix; + switch (type) { + case BLANK: + fwrite("_:", 1, 2, fd); + fwrite(str->buf, 1, str->n_bytes - 1, fd); + break; + case QNAME: + if (!serd_namespaces_expand(ns, str, &uri_prefix, &uri_suffix)) { + fprintf(stderr, "error: undefined namespace prefix `%s'\n", str->buf); + return false; + } + fwrite("<", 1, 1, fd); + serd_write_ascii(uri_prefix.buf, uri_prefix.len, fd, '>'); + serd_write_ascii(uri_suffix.buf, uri_suffix.len, fd, '>'); + fwrite(">", 1, 1, fd); + break; + case URI: + if (serd_uri_string_is_relative(str->buf)) { + SerdURI uri; + if (serd_uri_parse(str->buf, &uri)) { + SerdURI abs_uri; + if (serd_uri_resolve(&uri, base_uri, &abs_uri)) { + fwrite("<", 1, 1, fd); + serd_write_uri(fd, &abs_uri); + fwrite(">", 1, 1, fd); + return true; + } + } + } else { + fwrite("<", 1, 1, fd); + serd_write_ascii(str->buf, str->n_bytes - 1, fd, '>'); + fwrite(">", 1, 1, fd); + return true; + } + return false; + case LITERAL: + fwrite("\"", 1, 1, fd); + serd_write_ascii(str->buf, str->n_bytes - 1, fd, '"'); + fwrite("\"", 1, 1, fd); + if (lang) { + fwrite("@\"", 1, 2, fd); + fwrite(lang->buf, 1, lang->n_bytes - 1, fd); + fwrite("\"", 1, 1, fd); + } else if (datatype) { + fwrite("^^", 1, 2, fd); + serd_write_node(fd, base_uri, ns, URI, datatype, NULL, NULL); + } + break; + } + return true; +} + |