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-rw-r--r--src/writer.c210
1 files changed, 135 insertions, 75 deletions
diff --git a/src/writer.c b/src/writer.c
index a9574d76..75af4b57 100644
--- a/src/writer.c
+++ b/src/writer.c
@@ -145,17 +145,133 @@ sink(const void* buf, size_t len, SerdWriter* writer)
}
}
+// Parse a UTF-8 character, set *size to the length, and return the code point
+static inline uint32_t
+parse_utf8_char(SerdWriter* writer, const uint8_t* utf8, size_t* size)
+{
+ uint32_t c = 0;
+ if ((utf8[0] & 0x80) == 0) { // Starts with `0'
+ *size = 1;
+ c = utf8[0];
+ } else if ((utf8[0] & 0xE0) == 0xC0) { // Starts with `110'
+ *size = 2;
+ c = utf8[0] & 0x1F;
+ } else if ((utf8[0] & 0xF0) == 0xE0) { // Starts with `1110'
+ *size = 3;
+ c = utf8[0] & 0x0F;
+ } else if ((utf8[0] & 0xF8) == 0xF0) { // Starts with `11110'
+ *size = 4;
+ c = utf8[0] & 0x07;
+ } else {
+ w_err(writer, SERD_ERR_BAD_ARG, "invalid UTF-8: %X\n", utf8[0]);
+ *size = 0;
+ return 0;
+ }
+
+ size_t i = 0;
+ uint8_t in = utf8[i++];
+
+#define READ_BYTE() \
+ in = utf8[i++] & 0x3f; \
+ c = (c << 6) | in;
+
+ switch (*size) {
+ case 4: READ_BYTE();
+ case 3: READ_BYTE();
+ case 2: READ_BYTE();
+ }
+
+ return c;
+}
+
+// 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)
+{
+ const uint8_t replacement_char[] = { 0xEF, 0xBF, 0xBD };
+ char escape[11] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+ const uint8_t in = utf8[0];
+
+ uint32_t c = parse_utf8_char(writer, utf8, size);
+ switch (*size) {
+ case 0:
+ w_err(writer, SERD_ERR_BAD_ARG, "invalid UTF-8: %X\n", in);
+ return sink(replacement_char, sizeof(replacement_char), writer);
+ case 1:
+ snprintf(escape, sizeof(escape), "\\u%04X", in);
+ 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 uint8_t 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 uint8_t* 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;
+ }
+ }
+
+ if (j > i) {
+ // Bulk write all characters up to this special one
+ len += sink(&utf8[i], j - i, writer);
+ i = j;
+ continue;
+ }
+
+ // Write UTF-8 character
+ size_t size = 0;
+ len += write_character(writer, utf8 + i, &size);
+ i += size;
+
+ if (size == 0) {
+ return len;
+ }
+ }
+ return len;
+}
+
static size_t
write_text(SerdWriter* writer, TextContext ctx,
const uint8_t* utf8, size_t n_bytes)
{
- size_t len = 0;
- char escape[11] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+ 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] == '\\' || utf8[j] == '"'
+ if (utf8[j] == '\\' || utf8[j] == '"'
|| (!in_range(utf8[j], 0x20, 0x7E))) {
break;
}
@@ -174,82 +290,27 @@ write_text(SerdWriter* writer, TextContext ctx,
} else if (in == '\"' && i == n_bytes) {
len += sink("\\\"", 2, writer); continue; // '"' at string end
}
- } else {
+ } 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 '"':
- if (ctx == WRITE_STRING) {
- len += sink("\\\"", 2, writer);
- continue;
- } // else fall-through
+ case '\b': len += sink("\\b", 2, writer); continue;
+ case '\f': len += sink("\\f", 2, writer); continue;
+ case '"': len += sink("\\\"", 2, writer); continue;
default: break;
}
-
- if ((ctx == WRITE_STRING && in == '"') ||
- (ctx == WRITE_URI && in == '>')) {
- snprintf(escape, sizeof(escape), "\\u%04X",
- ctx == WRITE_STRING ? '"' : '>');
- len += sink(escape, 6, writer);
- continue;
- }
- }
-
- uint32_t c = 0;
- size_t size = 0;
- if ((in & 0x80) == 0) { // Starts with `0'
- c = in & 0x7F;
- if (in_range(c, 0x20, 0x7E)
- || (is_space(c) && ctx == WRITE_LONG_STRING)) {
- len += sink(&in, 1, writer); // Print ASCII character
- } else {
- snprintf(escape, sizeof(escape), "\\u%04X", c);
- len += sink(escape, 6, writer); // ASCII control character
- }
- 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 {
- w_err(writer, SERD_ERR_BAD_ARG, "invalid UTF-8: %X\n", in);
- const uint8_t replacement_char[] = { 0xEF, 0xBF, 0xBD };
- len += sink(replacement_char, sizeof(replacement_char), writer);
- return len;
- }
-
- if (ctx != WRITE_URI && !(writer->style & SERD_STYLE_ASCII)) {
- // Write UTF-8 character directly to UTF-8 output
- // TODO: Always parse and validate character?
- len += sink(utf8 + i - 1, size, writer);
- i += size - 1;
- continue;
}
-#define READ_BYTE() \
- in = utf8[i++] & 0x3f; \
- c = (c << 6) | in;
+ size_t size = 0;
+ len += write_character(writer, utf8 + i - 1, &size);
- switch (size) {
- case 4: READ_BYTE();
- case 3: READ_BYTE();
- case 2: READ_BYTE();
+ if (size == 0) {
+ return len;
}
- if (c < 0xFFFF) {
- snprintf(escape, sizeof(escape), "\\u%04X", c);
- len += sink(escape, 6, writer);
- } else {
- snprintf(escape, sizeof(escape), "\\U%08X", c);
- len += sink(escape, 10, writer);
- }
+ i += size - 1;
}
return len;
}
@@ -257,8 +318,7 @@ write_text(SerdWriter* writer, TextContext ctx,
static size_t
uri_sink(const void* buf, size_t len, void* stream)
{
- return write_text((SerdWriter*)stream, WRITE_URI,
- (const uint8_t*)buf, len);
+ return write_uri((SerdWriter*)stream, (const uint8_t*)buf, len);
}
static void
@@ -369,8 +429,8 @@ write_node(SerdWriter* writer,
return false;
}
sink("<", 1, writer);
- write_text(writer, WRITE_URI, uri_prefix.buf, uri_prefix.len);
- write_text(writer, WRITE_URI, uri_suffix.buf, uri_suffix.len);
+ write_uri(writer, uri_prefix.buf, uri_prefix.len);
+ write_uri(writer, uri_suffix.buf, uri_suffix.len);
sink(">", 1, writer);
break;
case SERD_TURTLE:
@@ -420,9 +480,9 @@ write_node(SerdWriter* writer,
SerdNode prefix;
SerdChunk suffix;
if (serd_env_qualify(writer->env, node, &prefix, &suffix)) {
- write_text(writer, WRITE_URI, prefix.buf, prefix.n_bytes);
+ write_uri(writer, prefix.buf, prefix.n_bytes);
sink(":", 1, writer);
- write_text(writer, WRITE_URI, suffix.buf, suffix.len);
+ write_uri(writer, suffix.buf, suffix.len);
break;
}
}
@@ -442,7 +502,7 @@ write_node(SerdWriter* writer,
&uri, &writer->base_uri, root, uri_sink, writer);
}
} else {
- write_text(writer, WRITE_URI, node->buf, node->n_bytes);
+ write_uri(writer, node->buf, node->n_bytes);
}
sink(">", 1, writer);
default:
@@ -749,7 +809,7 @@ serd_writer_set_prefix(SerdWriter* writer,
sink("@prefix ", 8, writer);
sink(name->buf, name->n_bytes, writer);
sink(": <", 3, writer);
- write_text(writer, WRITE_URI, uri->buf, uri->n_bytes);
+ write_uri(writer, uri->buf, uri->n_bytes);
sink("> .\n", 4, writer);
}
writer->indent = 0;
generated by cgit v1.2.1 (git 2.18.0) at 2024-06-29 16:49:39 +0000