From 930b2bd2fb6e8739e71ad2c503087ae675ffe194 Mon Sep 17 00:00:00 2001 From: David Robillard Date: Sun, 4 Feb 2018 12:09:42 +0100 Subject: Factor out syntax-specific reader implementation --- src/n3.c | 1490 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1490 insertions(+) create mode 100644 src/n3.c (limited to 'src/n3.c') diff --git a/src/n3.c b/src/n3.c new file mode 100644 index 00000000..06fc8e80 --- /dev/null +++ b/src/n3.c @@ -0,0 +1,1490 @@ +/* + Copyright 2011-2017 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 "serd_internal.h" + +#include +#include +#include +#include +#include +#include +#include + +#include "reader.h" + +#define TRY_THROW(exp) if (!(exp)) goto except; +#define TRY_RET(exp) if (!(exp)) return 0; + +static inline bool +fancy_syntax(const SerdReader* reader) +{ + return reader->syntax == SERD_TURTLE || reader->syntax == SERD_TRIG; +} + +static bool +read_collection(SerdReader* reader, ReadContext ctx, Ref* dest); + +static bool +read_predicateObjectList(SerdReader* reader, ReadContext ctx, bool* ate_dot); + +static inline uint8_t +read_HEX(SerdReader* reader) +{ + const uint8_t c = peek_byte(reader); + if (is_xdigit(c)) { + return eat_byte_safe(reader, c); + } + return r_err(reader, SERD_ERR_BAD_SYNTAX, + "invalid hexadecimal digit `%c'\n", c); +} + +// Read UCHAR escape, initial \ is already eaten by caller +static inline bool +read_UCHAR(SerdReader* reader, Ref dest, uint32_t* char_code) +{ + const uint8_t b = peek_byte(reader); + unsigned length = 0; + switch (b) { + case 'U': + length = 8; + break; + case 'u': + length = 4; + break; + default: + return false; + } + eat_byte_safe(reader, b); + + uint8_t buf[9] = { 0, 0, 0, 0, 0, 0, 0, 0, 0 }; + for (unsigned i = 0; i < length; ++i) { + if (!(buf[i] = read_HEX(reader))) { + return false; + } + } + + uint32_t code; + sscanf((const char*)buf, "%X", &code); + + unsigned size = 0; + if (code < 0x00000080) { + size = 1; + } else if (code < 0x00000800) { + size = 2; + } else if (code < 0x00010000) { + size = 3; + } else if (code < 0x00110000) { + size = 4; + } else { + r_err(reader, SERD_ERR_BAD_SYNTAX, + "unicode character 0x%X out of range\n", code); + push_bytes(reader, dest, replacement_char, 3); + *char_code = 0xFFFD; + return true; + } + + // Build output in buf + // (Note # of bytes = # of leading 1 bits in first byte) + uint32_t c = code; + switch (size) { + case 4: + buf[3] = 0x80 | (uint8_t)(c & 0x3F); + c >>= 6; + c |= (16 << 12); // set bit 4 + case 3: + buf[2] = 0x80 | (uint8_t)(c & 0x3F); + c >>= 6; + c |= (32 << 6); // set bit 5 + case 2: + buf[1] = 0x80 | (uint8_t)(c & 0x3F); + c >>= 6; + c |= 0xC0; // set bits 6 and 7 + case 1: + buf[0] = (uint8_t)c; + } + + push_bytes(reader, dest, buf, size); + *char_code = code; + return true; +} + +// Read ECHAR escape, initial \ is already eaten by caller +static inline bool +read_ECHAR(SerdReader* reader, Ref dest, SerdNodeFlags* flags) +{ + const uint8_t c = peek_byte(reader); + switch (c) { + case 't': + eat_byte_safe(reader, 't'); + push_byte(reader, dest, '\t'); + return true; + case 'b': + eat_byte_safe(reader, 'b'); + push_byte(reader, dest, '\b'); + return true; + case 'n': + *flags |= SERD_HAS_NEWLINE; + eat_byte_safe(reader, 'n'); + push_byte(reader, dest, '\n'); + return true; + case 'r': + *flags |= SERD_HAS_NEWLINE; + eat_byte_safe(reader, 'r'); + push_byte(reader, dest, '\r'); + return true; + case 'f': + eat_byte_safe(reader, 'f'); + push_byte(reader, dest, '\f'); + return true; + case '\\': case '"': case '\'': + push_byte(reader, dest, eat_byte_safe(reader, c)); + return true; + default: + return false; + } +} + +static inline SerdStatus +bad_char(SerdReader* reader, const char* fmt, uint8_t c) +{ + // Skip bytes until the next start byte + for (uint8_t b = peek_byte(reader); (b & 0x80);) { + eat_byte_safe(reader, b); + b = peek_byte(reader); + } + + r_err(reader, SERD_ERR_BAD_SYNTAX, fmt, c); + return reader->strict ? SERD_ERR_BAD_SYNTAX : SERD_FAILURE; +} + +static SerdStatus +read_utf8_bytes(SerdReader* reader, uint8_t bytes[4], uint32_t* size, uint8_t c) +{ + *size = utf8_num_bytes(c); + if (*size <= 1 || *size > 4) { + return bad_char(reader, "invalid UTF-8 start 0x%X\n", c); + } + + bytes[0] = c; + for (unsigned i = 1; i < *size; ++i) { + if (((bytes[i] = peek_byte(reader)) & 0x80) == 0) { + return bad_char(reader, "invalid UTF-8 continuation 0x%X\n", + bytes[i]); + } + eat_byte_safe(reader, bytes[i]); + } + + return SERD_SUCCESS; +} + +static SerdStatus +read_utf8_character(SerdReader* reader, Ref dest, uint8_t c) +{ + uint32_t size; + uint8_t bytes[4]; + SerdStatus st = read_utf8_bytes(reader, bytes, &size, c); + if (st) { + push_bytes(reader, dest, replacement_char, 3); + } else { + push_bytes(reader, dest, bytes, size); + } + return st; +} + +static SerdStatus +read_utf8_code(SerdReader* reader, Ref dest, uint32_t* code, uint8_t c) +{ + uint32_t size; + uint8_t bytes[4]; + SerdStatus st = read_utf8_bytes(reader, bytes, &size, c); + if (st) { + push_bytes(reader, dest, replacement_char, 3); + return st; + } + + push_bytes(reader, dest, bytes, size); + *code = parse_counted_utf8_char(bytes, size); + return st; +} + +// Read one character (possibly multi-byte) +// The first byte, c, has already been eaten by caller +static inline SerdStatus +read_character(SerdReader* reader, Ref dest, SerdNodeFlags* flags, uint8_t c) +{ + if (!(c & 0x80)) { + switch (c) { + case 0xA: case 0xD: + *flags |= SERD_HAS_NEWLINE; + break; + case '"': case '\'': + *flags |= SERD_HAS_QUOTE; + break; + } + push_byte(reader, dest, c); + return SERD_SUCCESS; + } + return read_utf8_character(reader, dest, c); +} + +// [10] comment ::= '#' ( [^#xA #xD] )* +static void +read_comment(SerdReader* reader) +{ + eat_byte_safe(reader, '#'); + uint8_t c; + while (((c = peek_byte(reader)) != 0xA) && (c != 0xD) && c) { + eat_byte_safe(reader, c); + } +} + +// [24] ws ::= #x9 | #xA | #xD | #x20 | comment +static inline bool +read_ws(SerdReader* reader) +{ + const uint8_t c = peek_byte(reader); + switch (c) { + case 0x9: case 0xA: case 0xD: case 0x20: + eat_byte_safe(reader, c); + return true; + case '#': + read_comment(reader); + return true; + default: + return false; + } +} + +static inline bool +read_ws_star(SerdReader* reader) +{ + while (read_ws(reader)) {} + return true; +} + +static inline bool +peek_delim(SerdReader* reader, const char delim) +{ + read_ws_star(reader); + return peek_byte(reader) == delim; +} + +static inline bool +eat_delim(SerdReader* reader, const char delim) +{ + if (peek_delim(reader, delim)) { + eat_byte_safe(reader, delim); + return read_ws_star(reader); + } + return false; +} + +// STRING_LITERAL_LONG_QUOTE and STRING_LITERAL_LONG_SINGLE_QUOTE +// Initial triple quotes are already eaten by caller +static Ref +read_STRING_LITERAL_LONG(SerdReader* reader, SerdNodeFlags* flags, uint8_t q) +{ + Ref ref = push_node(reader, SERD_LITERAL, "", 0); + while (!reader->status) { + const uint8_t c = peek_byte(reader); + uint32_t code; + switch (c) { + case '\\': + eat_byte_safe(reader, c); + if (!read_ECHAR(reader, ref, flags) && + !read_UCHAR(reader, ref, &code)) { + r_err(reader, SERD_ERR_BAD_SYNTAX, + "invalid escape `\\%c'\n", peek_byte(reader)); + return pop_node(reader, ref); + } + break; + default: + if (c == q) { + eat_byte_safe(reader, q); + const uint8_t q2 = eat_byte_safe(reader, peek_byte(reader)); + const uint8_t q3 = peek_byte(reader); + if (q2 == q && q3 == q) { // End of string + eat_byte_safe(reader, q3); + return ref; + } + *flags |= SERD_HAS_QUOTE; + push_byte(reader, ref, c); + read_character(reader, ref, flags, q2); + } else { + read_character(reader, ref, flags, eat_byte_safe(reader, c)); + } + } + } + return ref; +} + +// STRING_LITERAL_QUOTE and STRING_LITERAL_SINGLE_QUOTE +// Initial quote is already eaten by caller +static Ref +read_STRING_LITERAL(SerdReader* reader, SerdNodeFlags* flags, uint8_t q) +{ + Ref ref = push_node(reader, SERD_LITERAL, "", 0); + while (!reader->status) { + const uint8_t c = peek_byte(reader); + uint32_t code = 0; + switch (c) { + case '\n': case '\r': + r_err(reader, SERD_ERR_BAD_SYNTAX, "line end in short string\n"); + return pop_node(reader, ref); + case '\\': + eat_byte_safe(reader, c); + if (!read_ECHAR(reader, ref, flags) && + !read_UCHAR(reader, ref, &code)) { + r_err(reader, SERD_ERR_BAD_SYNTAX, + "invalid escape `\\%c'\n", peek_byte(reader)); + return pop_node(reader, ref); + } + break; + default: + if (c == q) { + eat_byte_check(reader, q); + return ref; + } else { + read_character(reader, ref, flags, eat_byte_safe(reader, c)); + } + } + } + eat_byte_check(reader, q); + return ref; +} + +static Ref +read_String(SerdReader* reader, SerdNodeFlags* flags) +{ + const uint8_t q1 = peek_byte(reader); + eat_byte_safe(reader, q1); + + const uint8_t q2 = peek_byte(reader); + if (q2 != q1) { // Short string (not triple quoted) + return read_STRING_LITERAL(reader, flags, q1); + } + + eat_byte_safe(reader, q2); + const uint8_t q3 = peek_byte(reader); + if (q3 != q1) { // Empty short string ("" or '') + return push_node(reader, SERD_LITERAL, "", 0); + } + + if (!fancy_syntax(reader)) { + return r_err(reader, SERD_ERR_BAD_SYNTAX, + "syntax does not support long literals\n"); + } + + eat_byte_safe(reader, q3); + return read_STRING_LITERAL_LONG(reader, flags, q1); +} + +static inline bool +is_PN_CHARS_BASE(const uint32_t c) +{ + return ((c >= 0x00C0 && c <= 0x00D6) || (c >= 0x00D8 && c <= 0x00F6) || + (c >= 0x00F8 && c <= 0x02FF) || (c >= 0x0370 && c <= 0x037D) || + (c >= 0x037F && c <= 0x1FFF) || (c >= 0x200C && c <= 0x200D) || + (c >= 0x2070 && c <= 0x218F) || (c >= 0x2C00 && c <= 0x2FEF) || + (c >= 0x3001 && c <= 0xD7FF) || (c >= 0xF900 && c <= 0xFDCF) || + (c >= 0xFDF0 && c <= 0xFFFD) || (c >= 0x10000 && c <= 0xEFFFF)); +} + +static SerdStatus +read_PN_CHARS_BASE(SerdReader* reader, Ref dest) +{ + uint32_t code; + const uint8_t c = peek_byte(reader); + SerdStatus st = SERD_SUCCESS; + if (is_alpha(c)) { + push_byte(reader, dest, eat_byte_safe(reader, c)); + } else if (!(c & 0x80)) { + return SERD_FAILURE; + } else if ((st = read_utf8_code(reader, dest, &code, + eat_byte_safe(reader, c)))) { + return st; + } else if (!is_PN_CHARS_BASE(code)) { + r_err(reader, SERD_ERR_BAD_SYNTAX, + "invalid character U+%04X in name\n", code); + if (reader->strict) { + return SERD_ERR_BAD_SYNTAX; + } + } + return st; +} + +static inline bool +is_PN_CHARS(const uint32_t c) +{ + return (is_PN_CHARS_BASE(c) || c == 0xB7 || + (c >= 0x0300 && c <= 0x036F) || (c >= 0x203F && c <= 0x2040)); +} + +static SerdStatus +read_PN_CHARS(SerdReader* reader, Ref dest) +{ + uint32_t code; + const uint8_t c = peek_byte(reader); + SerdStatus st = SERD_SUCCESS; + if (is_alpha(c) || is_digit(c) || c == '_' || c == '-') { + push_byte(reader, dest, eat_byte_safe(reader, c)); + } else if (!(c & 0x80)) { + return SERD_FAILURE; + } else if ((st = read_utf8_code(reader, dest, &code, + eat_byte_safe(reader, c)))) { + return st; + } else if (!is_PN_CHARS(code)) { + r_err(reader, (st = SERD_ERR_BAD_SYNTAX), + "invalid character U+%04X in name\n", code); + } + return st; +} + +static bool +read_PERCENT(SerdReader* reader, Ref dest) +{ + push_byte(reader, dest, eat_byte_safe(reader, '%')); + const uint8_t h1 = read_HEX(reader); + const uint8_t h2 = read_HEX(reader); + if (h1 && h2) { + push_byte(reader, dest, h1); + push_byte(reader, dest, h2); + return true; + } + return false; +} + +static SerdStatus +read_PLX(SerdReader* reader, Ref dest) +{ + uint8_t c = peek_byte(reader); + switch (c) { + case '%': + if (!read_PERCENT(reader, dest)) { + return SERD_ERR_BAD_SYNTAX; + } + return SERD_SUCCESS; + case '\\': + eat_byte_safe(reader, c); + if (is_alpha(c = peek_byte(reader))) { + // Escapes like \u \n etc. are not supported + return SERD_ERR_BAD_SYNTAX; + } + // Allow escaping of pretty much any other character + push_byte(reader, dest, eat_byte_safe(reader, c)); + return SERD_SUCCESS; + default: + return SERD_FAILURE; + } +} + +static SerdStatus +read_PN_LOCAL(SerdReader* reader, Ref dest, bool* ate_dot) +{ + uint8_t c = peek_byte(reader); + SerdStatus st = SERD_SUCCESS; + switch (c) { + case '0': case '1': case '2': case '3': case '4': case '5': + case '6': case '7': case '8': case '9': case ':': case '_': + push_byte(reader, dest, eat_byte_safe(reader, c)); + break; + default: + if ((st = read_PLX(reader, dest)) > SERD_FAILURE) { + return st; + } else if (st != SERD_SUCCESS && read_PN_CHARS_BASE(reader, dest)) { + return SERD_FAILURE; + } + } + + while ((c = peek_byte(reader))) { // Middle: (PN_CHARS | '.' | ';')* + if (c == '.' || c == ':') { + push_byte(reader, dest, eat_byte_safe(reader, c)); + } else if ((st = read_PLX(reader, dest)) > SERD_FAILURE) { + return st; + } else if (st != SERD_SUCCESS && (st = read_PN_CHARS(reader, dest))) { + break; + } + } + + SerdNode* const n = deref(reader, dest); + if (n->buf[n->n_bytes - 1] == '.') { + // Ate trailing dot, pop it from stack/node and inform caller + --n->n_bytes; + serd_stack_pop(&reader->stack, 1); + *ate_dot = true; + } + + return (st > SERD_FAILURE) ? st : SERD_SUCCESS; +} + +// Read the remainder of a PN_PREFIX after some initial characters +static SerdStatus +read_PN_PREFIX_tail(SerdReader* reader, Ref dest) +{ + uint8_t c; + while ((c = peek_byte(reader))) { // Middle: (PN_CHARS | '.')* + if (c == '.') { + push_byte(reader, dest, eat_byte_safe(reader, c)); + } else if (read_PN_CHARS(reader, dest)) { + break; + } + } + + const SerdNode* const n = deref(reader, dest); + if (n->buf[n->n_bytes - 1] == '.' && read_PN_CHARS(reader, dest)) { + r_err(reader, SERD_ERR_BAD_SYNTAX, "prefix ends with `.'\n"); + return SERD_ERR_BAD_SYNTAX; + } + + return SERD_SUCCESS; +} + +static SerdStatus +read_PN_PREFIX(SerdReader* reader, Ref dest) +{ + if (!read_PN_CHARS_BASE(reader, dest)) { + return read_PN_PREFIX_tail(reader, dest); + } + return SERD_FAILURE; +} + +static Ref +read_LANGTAG(SerdReader* reader) +{ + uint8_t c = peek_byte(reader); + if (!is_alpha(c)) { + return r_err(reader, SERD_ERR_BAD_SYNTAX, "unexpected `%c'\n", c); + } + Ref ref = push_node(reader, SERD_LITERAL, "", 0); + push_byte(reader, ref, eat_byte_safe(reader, c)); + while ((c = peek_byte(reader)) && is_alpha(c)) { + push_byte(reader, ref, eat_byte_safe(reader, c)); + } + while (peek_byte(reader) == '-') { + push_byte(reader, ref, eat_byte_safe(reader, '-')); + while ((c = peek_byte(reader)) && (is_alpha(c) || is_digit(c))) { + push_byte(reader, ref, eat_byte_safe(reader, c)); + } + } + return ref; +} + +static bool +read_IRIREF_scheme(SerdReader* reader, Ref dest) +{ + uint8_t c = peek_byte(reader); + if (!isalpha(c)) { + return r_err(reader, SERD_ERR_BAD_SYNTAX, + "bad IRI scheme start `%c'\n", c); + } + + while ((c = peek_byte(reader))) { + if (c == '>') { + return r_err(reader, SERD_ERR_BAD_SYNTAX, "missing IRI scheme\n"); + } else if (!is_uri_scheme_char(c)) { + return r_err(reader, SERD_ERR_BAD_SYNTAX, + "bad IRI scheme char `%X'\n", c); + } + + push_byte(reader, dest, eat_byte_safe(reader, c)); + if (c == ':') { + return true; // End of scheme + } + } + + return false; +} + +static Ref +read_IRIREF(SerdReader* reader) +{ + TRY_RET(eat_byte_check(reader, '<')); + Ref ref = push_node(reader, SERD_URI, "", 0); + if (!fancy_syntax(reader) && !read_IRIREF_scheme(reader, ref)) { + return pop_node(reader, ref); + } + + uint32_t code = 0; + while (!reader->status) { + const uint8_t c = eat_byte_safe(reader, peek_byte(reader)); + switch (c) { + case '"': case '<': case '^': case '`': case '{': case '|': case '}': + r_err(reader, SERD_ERR_BAD_SYNTAX, + "invalid IRI character `%c'\n", c); + return pop_node(reader, ref); + case '>': + return ref; + case '\\': + if (!read_UCHAR(reader, ref, &code)) { + r_err(reader, SERD_ERR_BAD_SYNTAX, "invalid IRI escape\n"); + return pop_node(reader, ref); + } + switch (code) { + case 0: case ' ': case '<': case '>': + r_err(reader, SERD_ERR_BAD_SYNTAX, + "invalid escaped IRI character %X %c\n", code, code); + return pop_node(reader, ref); + } + break; + default: + if (c <= 0x20) { + if (isprint(c)) { + r_err(reader, SERD_ERR_BAD_SYNTAX, + "invalid IRI character `%c' (escape %%%02X)\n", c, c); + } else { + r_err(reader, SERD_ERR_BAD_SYNTAX, + "invalid IRI character (escape %%%02X)\n", c, c); + } + if (reader->strict) { + return pop_node(reader, ref); + } + reader->status = SERD_FAILURE; + push_byte(reader, ref, c); + } else if (!(c & 0x80)) { + push_byte(reader, ref, c); + } else if (read_utf8_character(reader, ref, c)) { + if (reader->strict) { + return pop_node(reader, ref); + } + reader->status = SERD_FAILURE; + } + } + } + return pop_node(reader, ref); +} + +static bool +read_PrefixedName(SerdReader* reader, Ref dest, bool read_prefix, bool* ate_dot) +{ + if (read_prefix && read_PN_PREFIX(reader, dest) > SERD_FAILURE) { + return false; + } else if (peek_byte(reader) != ':') { + return false; + } + + push_byte(reader, dest, eat_byte_safe(reader, ':')); + return read_PN_LOCAL(reader, dest, ate_dot) <= SERD_FAILURE; +} + +static bool +read_0_9(SerdReader* reader, Ref str, bool at_least_one) +{ + unsigned count = 0; + for (uint8_t c; is_digit((c = peek_byte(reader))); ++count) { + push_byte(reader, str, eat_byte_safe(reader, c)); + } + if (at_least_one && count == 0) { + r_err(reader, SERD_ERR_BAD_SYNTAX, "expected digit\n"); + } + return count; +} + +static bool +read_number(SerdReader* reader, Ref* dest, Ref* datatype, bool* ate_dot) +{ + #define XSD_DECIMAL NS_XSD "decimal" + #define XSD_DOUBLE NS_XSD "double" + #define XSD_INTEGER NS_XSD "integer" + Ref ref = push_node(reader, SERD_LITERAL, "", 0); + uint8_t c = peek_byte(reader); + bool has_decimal = false; + if (c == '-' || c == '+') { + push_byte(reader, ref, eat_byte_safe(reader, c)); + } + if ((c = peek_byte(reader)) == '.') { + has_decimal = true; + // decimal case 2 (e.g. '.0' or `-.0' or `+.0') + push_byte(reader, ref, eat_byte_safe(reader, c)); + TRY_THROW(read_0_9(reader, ref, true)); + } else { + // all other cases ::= ( '-' | '+' ) [0-9]+ ( . )? ( [0-9]+ )? ... + TRY_THROW(is_digit(c)); + read_0_9(reader, ref, true); + if ((c = peek_byte(reader)) == '.') { + has_decimal = true; + + // Annoyingly, dot can be end of statement, so tentatively eat + eat_byte_safe(reader, c); + c = peek_byte(reader); + if (!is_digit(c) && c != 'e' && c != 'E') { + *dest = ref; + *ate_dot = true; // Force caller to deal with stupid grammar + return true; // Next byte is not a number character, done + } + + push_byte(reader, ref, '.'); + read_0_9(reader, ref, false); + } + } + c = peek_byte(reader); + if (c == 'e' || c == 'E') { + // double + push_byte(reader, ref, eat_byte_safe(reader, c)); + switch ((c = peek_byte(reader))) { + case '+': case '-': + push_byte(reader, ref, eat_byte_safe(reader, c)); + default: break; + } + TRY_THROW(read_0_9(reader, ref, true)); + *datatype = push_node(reader, SERD_URI, + XSD_DOUBLE, sizeof(XSD_DOUBLE) - 1); + } else if (has_decimal) { + *datatype = push_node(reader, SERD_URI, + XSD_DECIMAL, sizeof(XSD_DECIMAL) - 1); + } else { + *datatype = push_node(reader, SERD_URI, + XSD_INTEGER, sizeof(XSD_INTEGER) - 1); + } + *dest = ref; + return true; +except: + pop_node(reader, *datatype); + pop_node(reader, ref); + return r_err(reader, SERD_ERR_BAD_SYNTAX, "bad number syntax\n"); +} + +static bool +read_iri(SerdReader* reader, Ref* dest, bool* ate_dot) +{ + switch (peek_byte(reader)) { + case '<': + *dest = read_IRIREF(reader); + return true; + default: + *dest = push_node(reader, SERD_CURIE, "", 0); + return read_PrefixedName(reader, *dest, true, ate_dot); + } +} + +static bool +read_literal(SerdReader* reader, Ref* dest, + Ref* datatype, Ref* lang, SerdNodeFlags* flags, bool* ate_dot) +{ + Ref str = read_String(reader, flags); + if (!str) { + return false; + } + + switch (peek_byte(reader)) { + case '@': + eat_byte_safe(reader, '@'); + TRY_THROW(*lang = read_LANGTAG(reader)); + break; + case '^': + eat_byte_safe(reader, '^'); + eat_byte_check(reader, '^'); + TRY_THROW(read_iri(reader, datatype, ate_dot)); + break; + } + *dest = str; + return true; +except: + *datatype = pop_node(reader, *datatype); + *lang = pop_node(reader, *lang); + pop_node(reader, str); + return r_err(reader, SERD_ERR_BAD_SYNTAX, "bad literal syntax\n"); +} + +inline static bool +is_token_end(uint8_t c) +{ + switch (c) { + case 0x9: case 0xA: case 0xD: case 0x20: case '\0': + case '#': case '.': case ';': case '<': + return true; + default: + return false; + } +} + +static bool +read_verb(SerdReader* reader, Ref* dest) +{ + if (peek_byte(reader) == '<') { + return (*dest = read_IRIREF(reader)); + } + + /* Either a qname, or "a". Read the prefix first, and if it is in fact + "a", produce that instead. + */ + *dest = push_node(reader, SERD_CURIE, "", 0); + SerdNode* node = deref(reader, *dest); + const SerdStatus st = read_PN_PREFIX(reader, *dest); + bool ate_dot = false; + if (!st && node->n_bytes == 1 && node->buf[0] == 'a' && + is_token_end(peek_byte(reader))) { + pop_node(reader, *dest); + return (*dest = push_node(reader, SERD_URI, NS_RDF "type", 47)); + } else if (st > SERD_FAILURE || + !read_PrefixedName(reader, *dest, false, &ate_dot) || + ate_dot) { + *dest = pop_node(reader, *dest); + return r_err(reader, SERD_ERR_BAD_SYNTAX, "bad verb\n"); + } + + return true; +} + +static Ref +read_BLANK_NODE_LABEL(SerdReader* reader, bool* ate_dot) +{ + eat_byte_safe(reader, '_'); + eat_byte_check(reader, ':'); + Ref ref = push_node(reader, SERD_BLANK, + reader->bprefix ? (char*)reader->bprefix : "", + reader->bprefix_len); + + uint8_t c = peek_byte(reader); // First: (PN_CHARS | '_' | [0-9]) + if (is_digit(c) || c == '_') { + push_byte(reader, ref, eat_byte_safe(reader, c)); + } else if (read_PN_CHARS(reader, ref)) { + r_err(reader, SERD_ERR_BAD_SYNTAX, "invalid name start character\n"); + return pop_node(reader, ref); + } + + while ((c = peek_byte(reader))) { // Middle: (PN_CHARS | '.')* + if (c == '.') { + push_byte(reader, ref, eat_byte_safe(reader, c)); + } else if (read_PN_CHARS(reader, ref)) { + break; + } + } + + SerdNode* n = deref(reader, ref); + if (n->buf[n->n_bytes - 1] == '.' && read_PN_CHARS(reader, ref)) { + // Ate trailing dot, pop it from stack/node and inform caller + --n->n_bytes; + serd_stack_pop(&reader->stack, 1); + *ate_dot = true; + } + + if (reader->syntax == SERD_TURTLE) { + if (is_digit(n->buf[reader->bprefix_len + 1])) { + if ((n->buf[reader->bprefix_len]) == 'b') { + ((char*)n->buf)[reader->bprefix_len] = 'B'; // Prevent clash + reader->seen_genid = true; + } else if (reader->seen_genid && + n->buf[reader->bprefix_len] == 'B') { + r_err(reader, SERD_ERR_ID_CLASH, + "found both `b' and `B' blank IDs, prefix required\n"); + return pop_node(reader, ref); + } + } + } + return ref; +} + +static Ref +read_blankName(SerdReader* reader) +{ + eat_byte_safe(reader, '='); + if (eat_byte_check(reader, '=') != '=') { + return r_err(reader, SERD_ERR_BAD_SYNTAX, "expected `='\n"); + } + + Ref subject = 0; + bool ate_dot = false; + read_ws_star(reader); + read_iri(reader, &subject, &ate_dot); + return subject; +} + +static bool +read_anon(SerdReader* reader, ReadContext ctx, bool subject, Ref* dest) +{ + const SerdStatementFlags old_flags = *ctx.flags; + bool empty; + eat_byte_safe(reader, '['); + if ((empty = peek_delim(reader, ']'))) { + *ctx.flags |= (subject) ? SERD_EMPTY_S : SERD_EMPTY_O; + } else { + *ctx.flags |= (subject) ? SERD_ANON_S_BEGIN : SERD_ANON_O_BEGIN; + if (peek_delim(reader, '=')) { + if (!(*dest = read_blankName(reader)) || + !eat_delim(reader, ';')) { + return false; + } + } + } + + if (!*dest) { + *dest = blank_id(reader); + } + if (ctx.subject) { + TRY_RET(emit_statement(reader, ctx, *dest, 0, 0)); + } + + ctx.subject = *dest; + if (!empty) { + *ctx.flags &= ~(SERD_LIST_CONT); + if (!subject) { + *ctx.flags |= SERD_ANON_CONT; + } + bool ate_dot_in_list = false; + read_predicateObjectList(reader, ctx, &ate_dot_in_list); + if (ate_dot_in_list) { + 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)); + } + *ctx.flags = old_flags; + } + return (eat_byte_check(reader, ']') == ']'); +} + +/* If emit is true: recurses, calling statement_sink for every statement + encountered, and leaves stack in original calling state (i.e. pops + everything it pushes). */ +static bool +read_object(SerdReader* reader, ReadContext* ctx, bool emit, bool* ate_dot) +{ + static const char* const XSD_BOOLEAN = NS_XSD "boolean"; + static const size_t XSD_BOOLEAN_LEN = 40; + +#ifndef NDEBUG + const size_t orig_stack_size = reader->stack.size; +#endif + + bool ret = false; + bool simple = (ctx->subject != 0); + SerdNode* node = NULL; + Ref o = 0; + Ref datatype = 0; + Ref lang = 0; + uint32_t flags = 0; + const uint8_t c = peek_byte(reader); + if (!fancy_syntax(reader)) { + switch (c) { + case '"': case ':': case '<': case '_': break; + default: return r_err(reader, SERD_ERR_BAD_SYNTAX, + "expected: ':', '<', or '_'\n"); + } + } + switch (c) { + case '\0': case ')': + return r_err(reader, SERD_ERR_BAD_SYNTAX, "expected object\n"); + case '[': + simple = false; + TRY_THROW(ret = read_anon(reader, *ctx, false, &o)); + break; + case '(': + simple = false; + TRY_THROW(ret = read_collection(reader, *ctx, &o)); + break; + case '_': + TRY_THROW(ret = (o = read_BLANK_NODE_LABEL(reader, ate_dot))); + break; + case '<': case ':': + TRY_THROW(ret = read_iri(reader, &o, ate_dot)); + break; + case '+': case '-': case '.': case '0': case '1': case '2': case '3': + case '4': case '5': case '6': case '7': case '8': case '9': + TRY_THROW(ret = read_number(reader, &o, &datatype, ate_dot)); + break; + case '\"': + case '\'': + TRY_THROW(ret = read_literal(reader, &o, &datatype, &lang, &flags, ate_dot)); + break; + default: + /* Either a boolean literal, or a qname. Read the prefix first, and if + it is in fact a "true" or "false" literal, produce that instead. + */ + node = deref(reader, o = push_node(reader, SERD_CURIE, "", 0)); + while (!read_PN_CHARS_BASE(reader, o)) {} + if ((node->n_bytes == 4 && !memcmp(node->buf, "true", 4)) || + (node->n_bytes == 5 && !memcmp(node->buf, "false", 5))) { + node->type = SERD_LITERAL; + datatype = push_node( + reader, SERD_URI, XSD_BOOLEAN, XSD_BOOLEAN_LEN); + ret = true; + } else if (read_PN_PREFIX_tail(reader, o) > SERD_FAILURE) { + ret = false; + } else { + if (!(ret = read_PrefixedName(reader, o, false, ate_dot))) { + r_err(reader, SERD_ERR_BAD_SYNTAX, "expected prefixed name\n"); + } + } + } + + if (simple && o) { + deref(reader, o)->flags = flags; + } + + if (ret && emit && simple) { + ret = emit_statement(reader, *ctx, o, datatype, lang); + } else if (ret && !emit) { + ctx->object = o; + ctx->datatype = datatype; + ctx->lang = lang; + return true; + } + +except: + pop_node(reader, lang); + pop_node(reader, datatype); + pop_node(reader, o); +#ifndef NDEBUG + assert(reader->stack.size == orig_stack_size); +#endif + return ret; +} + +static bool +read_objectList(SerdReader* reader, ReadContext ctx, bool* ate_dot) +{ + TRY_RET(read_object(reader, &ctx, true, ate_dot)); + if (!fancy_syntax(reader) && peek_delim(reader, ',')) { + return r_err(reader, SERD_ERR_BAD_SYNTAX, + "syntax does not support abbreviation\n"); + } + + while (!*ate_dot && eat_delim(reader, ',')) { + TRY_RET(read_object(reader, &ctx, true, ate_dot)); + } + return true; +} + +static bool +read_predicateObjectList(SerdReader* reader, ReadContext ctx, bool* ate_dot) +{ + while (read_verb(reader, &ctx.predicate) && + read_ws_star(reader) && + read_objectList(reader, ctx, ate_dot)) { + ctx.predicate = pop_node(reader, ctx.predicate); + if (*ate_dot) { + return true; + } + + bool ate_semi = false; + uint8_t c; + do { + read_ws_star(reader); + switch (c = peek_byte(reader)) { + case 0: + return r_err(reader, SERD_ERR_BAD_SYNTAX, + "unexpected end of file\n"); + case '.': case ']': case '}': + return true; + case ';': + eat_byte_safe(reader, c); + ate_semi = true; + } + } while (c == ';'); + + if (!ate_semi) { + return r_err(reader, SERD_ERR_BAD_SYNTAX, "missing ';' or '.'\n"); + } + } + + return pop_node(reader, ctx.predicate); +} + +static bool +end_collection(SerdReader* reader, ReadContext ctx, Ref n1, Ref n2, bool ret) +{ + pop_node(reader, n2); + pop_node(reader, n1); + *ctx.flags &= ~SERD_LIST_CONT; + return ret && (eat_byte_safe(reader, ')') == ')'); +} + +static bool +read_collection(SerdReader* reader, ReadContext ctx, Ref* dest) +{ + eat_byte_safe(reader, '('); + bool end = peek_delim(reader, ')'); + *dest = end ? reader->rdf_nil : blank_id(reader); + if (ctx.subject) { + // subject predicate _:head + *ctx.flags |= (end ? 0 : SERD_LIST_O_BEGIN); + TRY_RET(emit_statement(reader, ctx, *dest, 0, 0)); + *ctx.flags |= SERD_LIST_CONT; + } else { + *ctx.flags |= (end ? 0 : SERD_LIST_S_BEGIN); + } + + if (end) { + return end_collection(reader, ctx, 0, 0, true); + } + + /* The order of node allocation here is necessarily not in stack order, + so we create two nodes and recycle them throughout. */ + Ref n1 = push_node_padded(reader, genid_size(reader), SERD_BLANK, "", 0); + Ref n2 = 0; + Ref node = n1; + Ref rest = 0; + + ctx.subject = *dest; + while (!(end = peek_delim(reader, ')'))) { + // _:node rdf:first object + ctx.predicate = reader->rdf_first; + bool ate_dot = false; + if (!read_object(reader, &ctx, true, &ate_dot) || ate_dot) { + return end_collection(reader, ctx, n1, n2, false); + } + + if (!(end = peek_delim(reader, ')'))) { + /* Give rest a new ID. Done as late as possible to ensure it is + used and > IDs generated by read_object above. */ + if (!rest) { + rest = n2 = blank_id(reader); // First pass, push + } else { + set_blank_id(reader, rest, genid_size(reader)); + } + } + + // _:node rdf:rest _:rest + *ctx.flags |= SERD_LIST_CONT; + ctx.predicate = reader->rdf_rest; + TRY_RET(emit_statement(reader, ctx, + (end ? reader->rdf_nil : rest), 0, 0)); + + ctx.subject = rest; // _:node = _:rest + rest = node; // _:rest = (old)_:node + node = ctx.subject; // invariant + } + + return end_collection(reader, ctx, n1, n2, true); +} + +static Ref +read_subject(SerdReader* reader, ReadContext ctx, Ref* dest, char* s_type) +{ + bool ate_dot = false; + switch ((*s_type = peek_byte(reader))) { + case '[': + read_anon(reader, ctx, true, dest); + break; + case '(': + read_collection(reader, ctx, dest); + break; + case '_': + *dest = read_BLANK_NODE_LABEL(reader, &ate_dot); + break; + default: + TRY_RET(read_iri(reader, dest, &ate_dot)); + } + return ate_dot ? pop_node(reader, *dest) : *dest; +} + +static Ref +read_labelOrSubject(SerdReader* reader, ReadContext ctx) +{ + Ref subject = 0; + bool ate_dot = false; + switch (peek_byte(reader)) { + case '[': + eat_byte_safe(reader, '['); + read_ws_star(reader); + TRY_RET(eat_byte_check(reader, ']')); + return blank_id(reader); + case '_': + return read_BLANK_NODE_LABEL(reader, &ate_dot); + default: + read_iri(reader, &subject, &ate_dot); + } + return subject; +} + +static bool +read_triples(SerdReader* reader, ReadContext ctx, bool* ate_dot) +{ + bool ret = false; + if (ctx.subject) { + read_ws_star(reader); + switch (peek_byte(reader)) { + case '.': + *ate_dot = eat_byte_safe(reader, '.'); + return r_err(reader, SERD_ERR_BAD_SYNTAX, "syntax error\n"); + case '}': + return false; + } + ret = read_predicateObjectList(reader, ctx, ate_dot); + } + ctx.subject = ctx.predicate = 0; + return ret; +} + +static bool +read_base(SerdReader* reader, bool sparql, bool token) +{ + if (token) { + TRY_RET(eat_string(reader, "base", 4)); + } + + Ref uri; + read_ws_star(reader); + TRY_RET(uri = read_IRIREF(reader)); + if (reader->base_sink) { + reader->base_sink(reader->handle, deref(reader, uri)); + } + pop_node(reader, uri); + + read_ws_star(reader); + if (!sparql) { + return eat_byte_check(reader, '.'); + } else if (peek_byte(reader) == '.') { + return r_err(reader, SERD_ERR_BAD_SYNTAX, + "full stop after SPARQL BASE\n"); + } + return true; +} + +static bool +read_prefixID(SerdReader* reader, bool sparql, bool token) +{ + if (token) { + TRY_RET(eat_string(reader, "prefix", 6)); + } + + read_ws_star(reader); + bool ret = true; + Ref name = push_node(reader, SERD_LITERAL, "", 0); + if (read_PN_PREFIX(reader, name) > SERD_FAILURE) { + return pop_node(reader, name); + } + + if (eat_byte_check(reader, ':') != ':') { + return pop_node(reader, name); + } + + read_ws_star(reader); + const Ref uri = read_IRIREF(reader); + if (!uri) { + pop_node(reader, name); + return false; + } + + if (reader->prefix_sink) { + ret = !reader->prefix_sink(reader->handle, + deref(reader, name), + deref(reader, uri)); + } + pop_node(reader, uri); + pop_node(reader, name); + if (!sparql) { + read_ws_star(reader); + return eat_byte_check(reader, '.'); + } + return ret; +} + +static bool +read_directive(SerdReader* reader) +{ + const bool sparql = peek_byte(reader) != '@'; + if (!sparql) { + eat_byte_safe(reader, '@'); + switch (peek_byte(reader)) { + case 'B': case 'P': + return r_err(reader, SERD_ERR_BAD_SYNTAX, + "uppercase directive\n"); + } + } + + switch (peek_byte(reader)) { + case 'B': case 'b': return read_base(reader, sparql, true); + case 'P': case 'p': return read_prefixID(reader, sparql, true); + default: + return r_err(reader, SERD_ERR_BAD_SYNTAX, "invalid directive\n"); + } + + return true; +} + +static bool +read_wrappedGraph(SerdReader* reader, ReadContext* ctx) +{ + bool ate_dot = false; + char s_type = 0; + TRY_RET(eat_byte_check(reader, '{')); + read_ws_star(reader); + while (peek_byte(reader) != '}') { + ctx->subject = 0; + Ref subj = read_subject(reader, *ctx, &ctx->subject, &s_type); + if (!subj && ctx->subject) { + return r_err(reader, SERD_ERR_BAD_SYNTAX, "bad subject\n"); + } else if (!subj) { + return false; + } else if (!read_triples(reader, *ctx, &ate_dot) && s_type != '[') { + return r_err(reader, SERD_ERR_BAD_SYNTAX, + "missing predicate object list\n"); + } + pop_node(reader, subj); + read_ws_star(reader); + if (peek_byte(reader) == '.') { + eat_byte_safe(reader, '.'); + } + read_ws_star(reader); + } + return eat_byte_check(reader, '}'); +} + +static int +tokcmp(SerdReader* reader, Ref ref, const char* tok, size_t n) +{ + SerdNode* node = deref(reader, ref); + if (!node || node->n_bytes != n) { + return -1; + } + return serd_strncasecmp((const char*)node->buf, tok, n); +} + +bool +read_n3_statement(SerdReader* reader) +{ + SerdStatementFlags flags = 0; + ReadContext ctx = { 0, 0, 0, 0, 0, 0, &flags }; + Ref subj = 0; + bool ate_dot = false; + char s_type = 0; + bool ret = true; + read_ws_star(reader); + switch (peek_byte(reader)) { + case '\0': + reader->source.eof = true; + return reader->status <= SERD_FAILURE; + case '@': + if (!fancy_syntax(reader)) { + return r_err(reader, SERD_ERR_BAD_SYNTAX, + "syntax does not support directives\n"); + } + TRY_RET(read_directive(reader)); + read_ws_star(reader); + break; + case '{': + if (reader->syntax == SERD_TRIG) { + TRY_RET(read_wrappedGraph(reader, &ctx)); + read_ws_star(reader); + } else { + return r_err(reader, SERD_ERR_BAD_SYNTAX, + "syntax does not support graphs\n"); + } + break; + default: + subj = read_subject(reader, ctx, &ctx.subject, &s_type); + if (!tokcmp(reader, ctx.subject, "base", 4)) { + ret = read_base(reader, true, false); + } else if (!tokcmp(reader, ctx.subject, "prefix", 6)) { + ret = read_prefixID(reader, true, false); + } else if (!tokcmp(reader, ctx.subject, "graph", 5)) { + read_ws_star(reader); + TRY_RET((ctx.graph = read_labelOrSubject(reader, ctx))); + read_ws_star(reader); + TRY_RET(read_wrappedGraph(reader, &ctx)); + read_ws_star(reader); + } else if (read_ws_star(reader) && peek_byte(reader) == '{') { + if (s_type == '(' || (s_type == '[' && !*ctx.flags)) { + return r_err(reader, SERD_ERR_BAD_SYNTAX, + "invalid graph name\n"); + } + ctx.graph = subj; + ctx.subject = subj = 0; + TRY_RET(read_wrappedGraph(reader, &ctx)); + read_ws_star(reader); + } else if (!subj) { + ret = r_err(reader, SERD_ERR_BAD_SYNTAX, "bad subject\n"); + } else if (!read_triples(reader, ctx, &ate_dot)) { + ret = (s_type == '['); + } else if (!ate_dot) { + read_ws_star(reader); + ret = (eat_byte_check(reader, '.') == '.'); + } + pop_node(reader, subj); + break; + } + return ret; +} + +static void +skip_until(SerdReader* reader, uint8_t byte) +{ + for (uint8_t c = 0; (c = peek_byte(reader)) && c != byte;) { + eat_byte_safe(reader, c); + } +} + +bool +read_turtleTrigDoc(SerdReader* reader) +{ + while (!reader->source.eof) { + if (!read_n3_statement(reader)) { + if (reader->strict) { + return 0; + } + skip_until(reader, '\n'); + reader->status = SERD_SUCCESS; + } + } + return reader->status <= SERD_FAILURE; +} + +bool +read_nquadsDoc(SerdReader* reader) +{ + while (!reader->source.eof) { + SerdStatementFlags flags = 0; + ReadContext ctx = { 0, 0, 0, 0, 0, 0, &flags }; + bool ate_dot = false; + char s_type = false; + read_ws_star(reader); + if (peek_byte(reader) == '\0') { + reader->source.eof = true; + break; + } else if (peek_byte(reader) == '@') { + return r_err(reader, SERD_ERR_BAD_SYNTAX, + "syntax does not support directives\n"); + } + + // subject predicate object + if (!(ctx.subject = read_subject(reader, ctx, &ctx.subject, &s_type)) || + !read_ws_star(reader) || + !(ctx.predicate = read_IRIREF(reader)) || + !read_ws_star(reader) || + !read_object(reader, &ctx, false, &ate_dot)) { + return false; + } + + if (!ate_dot) { // graphLabel? + TRY_RET(read_ws_star(reader)); + switch (peek_byte(reader)) { + case '.': + break; + case '_': + ctx.graph = read_BLANK_NODE_LABEL(reader, &ate_dot); + break; + default: + if (!(ctx.graph = read_IRIREF(reader))) { + return false; + } + } + + // Terminating '.' + TRY_RET(read_ws_star(reader)); + eat_byte_check(reader, '.'); + } + + TRY_RET(emit_statement(reader, ctx, ctx.object, ctx.datatype, ctx.lang)); + pop_node(reader, ctx.graph); + pop_node(reader, ctx.lang); + pop_node(reader, ctx.datatype); + pop_node(reader, ctx.object); + } + return reader->status <= SERD_FAILURE; +} -- cgit v1.2.1