diff options
| -rw-r--r-- | src/writer.c | 174 |
1 files changed, 97 insertions, 77 deletions
diff --git a/src/writer.c b/src/writer.c index 5efcb8c5..5b1bf412 100644 --- a/src/writer.c +++ b/src/writer.c @@ -278,7 +278,7 @@ esink(const void* buf, size_t len, SerdWriter* writer) return sink(buf, len, writer) == len ? SERD_SUCCESS : SERD_BAD_WRITE; } -// Write a single character, as an escape for single byte characters +// Write a single character as a Unicode escape // (Caller prints any single byte characters that don't need escaping) static size_t write_character(SerdWriter* writer, @@ -458,6 +458,78 @@ write_lname(SerdWriter* writer, const char* utf8, size_t n_bytes) return st; } +SERD_NODISCARD static size_t +write_long_string_escape(SerdWriter* const writer, + const size_t n_consecutive_quotes, + const bool is_last, + const char c) +{ + switch (c) { + case '\\': + return sink("\\\\", 2, writer); + + case '\b': + return sink("\\b", 2, writer); + + case '\n': + case '\r': + case '\t': + case '\f': + return sink(&c, 1, writer); // Write character as-is + + case '\"': + if (n_consecutive_quotes >= 3 || is_last) { + // Two quotes in a row, or quote at string end, escape + return sink("\\\"", 2, writer); + } + + return sink(&c, 1, writer); + + default: + break; + } + + return 0; +} + +SERD_NODISCARD static size_t +write_short_string_escape(SerdWriter* const writer, const char c) +{ + switch (c) { + case '\\': + return sink("\\\\", 2, writer); + case '\n': + return sink("\\n", 2, writer); + case '\r': + return sink("\\r", 2, writer); + case '\t': + return sink("\\t", 2, writer); + case '"': + return sink("\\\"", 2, writer); + default: + break; + } + + if (writer->syntax == SERD_TURTLE) { + switch (c) { + case '\b': + return sink("\\b", 2, writer); + case '\f': + return sink("\\f", 2, writer); + default: + break; + } + } + + return 0; +} + +static bool +text_must_escape(const char c) +{ + return c == '\\' || c == '"' || !in_range(c, 0x20, 0x7E); +} + SERD_NODISCARD static SerdStatus write_text(SerdWriter* writer, TextContext ctx, @@ -471,100 +543,48 @@ write_text(SerdWriter* writer, n_consecutive_quotes = 0; } - // Fast bulk write for long strings of printable ASCII + // Scan for the longest chunk of characters that can be written directly size_t j = i; - for (; j < n_bytes; ++j) { - if (utf8[j] == '\\' || utf8[j] == '"' || - (!in_range(utf8[j], 0x20, 0x7E))) { - break; - } + for (; j < n_bytes && !text_must_escape(utf8[j]); ++j) { } + // Write chunk as a single fast bulk write st = esink(&utf8[i], j - i, writer); if ((i = j) == n_bytes) { break; // Reached end } - const char in = utf8[i++]; + // Try to write character as a special short escape (newline and friends) + const char in = utf8[i++]; + size_t escape_len = 0; if (ctx == WRITE_LONG_STRING) { n_consecutive_quotes = (in == '\"') ? (n_consecutive_quotes + 1) : 0; - - switch (in) { - case '\\': - st = esink("\\\\", 2, writer); - continue; - case '\b': - st = esink("\\b", 2, writer); - continue; - case '\n': - case '\r': - case '\t': - case '\f': - st = esink(&in, 1, writer); // Write character as-is - continue; - case '\"': - if (n_consecutive_quotes >= 3 || i == n_bytes) { - // Two quotes in a row, or quote at string end, escape - st = esink("\\\"", 2, writer); - } else { - st = esink(&in, 1, writer); - } - continue; - default: - break; - } + escape_len = write_long_string_escape( + writer, n_consecutive_quotes, i == n_bytes, in); } else { - switch (in) { - case '\\': - st = esink("\\\\", 2, writer); - continue; - case '\n': - st = esink("\\n", 2, writer); - continue; - case '\r': - st = esink("\\r", 2, writer); - continue; - case '\t': - st = esink("\\t", 2, writer); - continue; - case '"': - st = esink("\\\"", 2, writer); - continue; - default: - break; - } - if (writer->syntax == SERD_TURTLE) { - switch (in) { - case '\b': - st = esink("\\b", 2, writer); - continue; - case '\f': - st = esink("\\f", 2, writer); - continue; - default: - break; - } - } + escape_len = write_short_string_escape(writer, in); } - // Write UTF-8 character - size_t size = 0; - write_character(writer, (const uint8_t*)utf8 + i - 1, &size, &st); - if (st && !(writer->flags & SERD_WRITE_LAX)) { - return st; - } + if (escape_len == 0) { + // No special escape for this character, write full Unicode escape + size_t size = 0; + write_character(writer, (const uint8_t*)utf8 + i - 1, &size, &st); + if (st && !(writer->flags & SERD_WRITE_LAX)) { + return st; + } - if (size == 0) { - // Corrupt input, write replacement character and scan to the next start - st = esink(replacement_char, sizeof(replacement_char), writer); - for (; i < n_bytes && (utf8[i] & 0x80); ++i) { + if (size == 0) { + // Corrupt input, write replacement character and scan to the next start + st = esink(replacement_char, sizeof(replacement_char), writer); + for (; i < n_bytes && (utf8[i] & 0x80); ++i) { + } + } else { + i += size - 1; } - } else { - i += size - 1; } } - return (writer->flags & SERD_WRITE_LAX) ? SERD_SUCCESS : st; + return SERD_SUCCESS; } typedef struct { |