#include "utf8.h" #include "escape.h" static inline size_t decode_hex_escape(const uint8_t *in, size_t pos, uint8_t *out, size_t *out_pos) { uint32_t cp = (unhex(in[pos + 2]) << 4U) | unhex(in[pos + 3]); *out_pos += utf8_encode(cp, (char *)&out[*out_pos]); return 2; } static size_t decode_octal_escape(const uint8_t *in, size_t pos, uint8_t *out, size_t *out_pos) { uint8_t c = in[pos + 1]; size_t extra = 0; int val = c - '0'; if (in[pos + 2] >= '0' && in[pos + 2] <= '7') { val = val * 8 + (in[pos + 2] - '0'); extra++; if (in[pos + 3] >= '0' && in[pos + 3] <= '7' && val * 8 + (in[pos + 3] - '0') <= 255) { val = val * 8 + (in[pos + 3] - '0'); extra++; } } *out_pos += utf8_encode((uint32_t)val, (char *)&out[*out_pos]); return extra; } static size_t decode_unicode_braced(const uint8_t *in, size_t pos, size_t end, uint8_t *out, size_t *out_pos) { uint32_t cp = 0; size_t i = pos + 3; while (i < end && is_xdigit(in[i])) { cp = (cp << 4) | unhex(in[i]); i++; } if (i < end && in[i] == '}') { *out_pos += utf8_encode(cp, (char *)&out[*out_pos]); return i - pos - 1; } out[(*out_pos)++] = 'u'; return 0; } static size_t decode_unicode_fixed(const uint8_t *in, size_t pos, size_t end, uint8_t *out, size_t *out_pos) { uint32_t cp = (unhex(in[pos + 2]) << 12U) | (unhex(in[pos + 3]) << 8U) | (unhex(in[pos + 4]) << 4U) | unhex(in[pos + 5]); if (cp >= 0xD800 && cp <= 0xDBFF && pos + 11 < end && in[pos + 6] == '\\' && in[pos + 7] == 'u' && is_xdigit(in[pos + 8]) && is_xdigit(in[pos + 9]) && is_xdigit(in[pos + 10]) && is_xdigit(in[pos + 11])) { uint32_t lo = (unhex(in[pos + 8]) << 12U) | (unhex(in[pos + 9]) << 8U) | (unhex(in[pos + 10]) << 4U) | unhex(in[pos + 11]); if (lo >= 0xDC00 && lo <= 0xDFFF) { cp = 0x10000 + ((cp - 0xD800) << 10) + (lo - 0xDC00); *out_pos += utf8_encode(cp, (char *)&out[*out_pos]); return 10; } } *out_pos += utf8_encode(cp, (char *)&out[*out_pos]); return 4; } size_t decode_escape(const uint8_t *in, size_t pos, size_t end, uint8_t *out, size_t *out_pos, uint8_t quote) { uint8_t c = in[pos + 1]; size_t advance = 0; switch (c) { case 'n': out[(*out_pos)++] = '\n'; break; case 't': out[(*out_pos)++] = '\t'; break; case 'r': out[(*out_pos)++] = '\r'; break; case 'v': out[(*out_pos)++] = '\v'; break; case 'f': out[(*out_pos)++] = '\f'; break; case 'b': out[(*out_pos)++] = '\b'; break; case '\\': out[(*out_pos)++] = '\\'; break; case '0': if (!(in[pos + 2] >= '0' && in[pos + 2] <= '7')) { out[(*out_pos)++] = '\0'; break; } __attribute__((fallthrough)); case '1': case '2': case '3': case '4': case '5': case '6': case '7': advance = decode_octal_escape(in, pos, out, out_pos); break; case 'x': if (pos + 3 < end && is_xdigit(in[pos + 2]) && is_xdigit(in[pos + 3])) { advance = decode_hex_escape(in, pos, out, out_pos); } else out[(*out_pos)++] = c; break; case 'u': if (pos + 2 < end && in[pos + 2] == '{') { advance = decode_unicode_braced(in, pos, end, out, out_pos); } else if ( pos + 5 < end && is_xdigit(in[pos + 2]) && is_xdigit(in[pos + 3]) && is_xdigit(in[pos + 4]) && is_xdigit(in[pos + 5]) ) advance = decode_unicode_fixed(in, pos, end, out, out_pos); else out[(*out_pos)++] = c; break; default: out[(*out_pos)++] = (c == quote) ? quote : c; break; } return advance; }