cosmopolitan/third_party/chibicc/unicode.c

187 lines
7.3 KiB
C
Raw Blame History

This file contains invisible Unicode characters!

This file contains invisible Unicode characters that may be processed differently from what appears below. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to reveal hidden characters.

#include "third_party/chibicc/chibicc.h"
// Encode a given character in UTF-8.
int encode_utf8(char *buf, uint32_t c) {
if (c <= 0x7F) {
buf[0] = c;
return 1;
}
if (c <= 0x7FF) {
buf[0] = 0b11000000 | (c >> 6);
buf[1] = 0b10000000 | (c & 0b00111111);
return 2;
}
if (c <= 0xFFFF) {
buf[0] = 0b11100000 | (c >> 12);
buf[1] = 0b10000000 | ((c >> 6) & 0b00111111);
buf[2] = 0b10000000 | (c & 0b00111111);
return 3;
}
buf[0] = 0b11110000 | (c >> 18);
buf[1] = 0b10000000 | ((c >> 12) & 0b00111111);
buf[2] = 0b10000000 | ((c >> 6) & 0b00111111);
buf[3] = 0b10000000 | (c & 0b00111111);
return 4;
}
// Read a UTF-8-encoded Unicode code point from a source file.
// We assume that source files are always in UTF-8.
//
// UTF-8 is a variable-width encoding in which one code point is
// encoded in one to four bytes. One byte UTF-8 code points are
// identical to ASCII. Non-ASCII characters are encoded using more
// than one byte.
uint32_t decode_utf8(char **new_pos, char *p) {
if ((unsigned char)*p < 128) {
*new_pos = p + 1;
return *p;
}
char *start = p;
int len;
uint32_t c;
if ((unsigned char)*p >= 0b11110000) {
len = 4;
c = *p & 0b111;
} else if ((unsigned char)*p >= 0b11100000) {
len = 3;
c = *p & 0b1111;
} else if ((unsigned char)*p >= 0b11000000) {
len = 2;
c = *p & 0b11111;
} else {
error_at(start, "invalid UTF-8 sequence");
}
for (int i = 1; i < len; i++) {
if ((unsigned char)p[i] >> 6 != 0b10)
error_at(start, "invalid UTF-8 sequence");
c = (c << 6) | (p[i] & 0b111111);
}
*new_pos = p + len;
return c;
}
static bool in_range(uint32_t *range, uint32_t c) {
for (int i = 0; range[i] != -1; i += 2)
if (range[i] <= c && c <= range[i + 1]) return true;
return false;
}
// C11 allows not only ASCII but some multibyte characters in certan
// Unicode ranges to be used in an identifier. See C11 Annex D for the
// details.
//
// This function returns true if a given character is acceptable as
// the first character of an identifier.
//
// For example, ¾ (U+00BE) is a valid identifier because characters in
// 0x00BE-0x00C0 are allowed, while neither ⟘ (U+27D8) nor ' '
// (U+3000, full-width space) are allowed because they are out of range.
bool is_ident1(uint32_t c) {
static uint32_t range[] = {
'_', '_', 'a', 'z', 'A', 'Z', '$', '$',
0x00A8, 0x00A8, 0x00AA, 0x00AA, 0x00AD, 0x00AD, 0x00AF, 0x00AF,
0x00B2, 0x00B5, 0x00B7, 0x00BA, 0x00BC, 0x00BE, 0x00C0, 0x00D6,
0x00D8, 0x00F6, 0x00F8, 0x00FF, 0x0100, 0x02FF, 0x0370, 0x167F,
0x1681, 0x180D, 0x180F, 0x1DBF, 0x1E00, 0x1FFF, 0x200B, 0x200D,
0x202A, 0x202E, 0x203F, 0x2040, 0x2054, 0x2054, 0x2060, 0x206F,
0x2070, 0x20CF, 0x2100, 0x218F, 0x2460, 0x24FF, 0x2776, 0x2793,
0x2C00, 0x2DFF, 0x2E80, 0x2FFF, 0x3004, 0x3007, 0x3021, 0x302F,
0x3031, 0x303F, 0x3040, 0xD7FF, 0xF900, 0xFD3D, 0xFD40, 0xFDCF,
0xFDF0, 0xFE1F, 0xFE30, 0xFE44, 0xFE47, 0xFFFD, 0x10000, 0x1FFFD,
0x20000, 0x2FFFD, 0x30000, 0x3FFFD, 0x40000, 0x4FFFD, 0x50000, 0x5FFFD,
0x60000, 0x6FFFD, 0x70000, 0x7FFFD, 0x80000, 0x8FFFD, 0x90000, 0x9FFFD,
0xA0000, 0xAFFFD, 0xB0000, 0xBFFFD, 0xC0000, 0xCFFFD, 0xD0000, 0xDFFFD,
0xE0000, 0xEFFFD, -1,
};
return in_range(range, c);
}
// Returns true if a given character is acceptable as a non-first
// character of an identifier.
bool is_ident2(uint32_t c) {
static uint32_t range[] = {
'0', '9', '$', '$', 0x0300, 0x036F, 0x1DC0,
0x1DFF, 0x20D0, 0x20FF, 0xFE20, 0xFE2F, -1,
};
return is_ident1(c) || in_range(range, c);
}
// Returns the number of columns needed to display a given
// character in a fixed-width font.
//
// Based on https://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
static int char_width(uint32_t c) {
static uint32_t range1[] = {
0x0000, 0x001F, 0x007f, 0x00a0, 0x0300, 0x036F, 0x0483, 0x0486,
0x0488, 0x0489, 0x0591, 0x05BD, 0x05BF, 0x05BF, 0x05C1, 0x05C2,
0x05C4, 0x05C5, 0x05C7, 0x05C7, 0x0600, 0x0603, 0x0610, 0x0615,
0x064B, 0x065E, 0x0670, 0x0670, 0x06D6, 0x06E4, 0x06E7, 0x06E8,
0x06EA, 0x06ED, 0x070F, 0x070F, 0x0711, 0x0711, 0x0730, 0x074A,
0x07A6, 0x07B0, 0x07EB, 0x07F3, 0x0901, 0x0902, 0x093C, 0x093C,
0x0941, 0x0948, 0x094D, 0x094D, 0x0951, 0x0954, 0x0962, 0x0963,
0x0981, 0x0981, 0x09BC, 0x09BC, 0x09C1, 0x09C4, 0x09CD, 0x09CD,
0x09E2, 0x09E3, 0x0A01, 0x0A02, 0x0A3C, 0x0A3C, 0x0A41, 0x0A42,
0x0A47, 0x0A48, 0x0A4B, 0x0A4D, 0x0A70, 0x0A71, 0x0A81, 0x0A82,
0x0ABC, 0x0ABC, 0x0AC1, 0x0AC5, 0x0AC7, 0x0AC8, 0x0ACD, 0x0ACD,
0x0AE2, 0x0AE3, 0x0B01, 0x0B01, 0x0B3C, 0x0B3C, 0x0B3F, 0x0B3F,
0x0B41, 0x0B43, 0x0B4D, 0x0B4D, 0x0B56, 0x0B56, 0x0B82, 0x0B82,
0x0BC0, 0x0BC0, 0x0BCD, 0x0BCD, 0x0C3E, 0x0C40, 0x0C46, 0x0C48,
0x0C4A, 0x0C4D, 0x0C55, 0x0C56, 0x0CBC, 0x0CBC, 0x0CBF, 0x0CBF,
0x0CC6, 0x0CC6, 0x0CCC, 0x0CCD, 0x0CE2, 0x0CE3, 0x0D41, 0x0D43,
0x0D4D, 0x0D4D, 0x0DCA, 0x0DCA, 0x0DD2, 0x0DD4, 0x0DD6, 0x0DD6,
0x0E31, 0x0E31, 0x0E34, 0x0E3A, 0x0E47, 0x0E4E, 0x0EB1, 0x0EB1,
0x0EB4, 0x0EB9, 0x0EBB, 0x0EBC, 0x0EC8, 0x0ECD, 0x0F18, 0x0F19,
0x0F35, 0x0F35, 0x0F37, 0x0F37, 0x0F39, 0x0F39, 0x0F71, 0x0F7E,
0x0F80, 0x0F84, 0x0F86, 0x0F87, 0x0F90, 0x0F97, 0x0F99, 0x0FBC,
0x0FC6, 0x0FC6, 0x102D, 0x1030, 0x1032, 0x1032, 0x1036, 0x1037,
0x1039, 0x1039, 0x1058, 0x1059, 0x1160, 0x11FF, 0x135F, 0x135F,
0x1712, 0x1714, 0x1732, 0x1734, 0x1752, 0x1753, 0x1772, 0x1773,
0x17B4, 0x17B5, 0x17B7, 0x17BD, 0x17C6, 0x17C6, 0x17C9, 0x17D3,
0x17DD, 0x17DD, 0x180B, 0x180D, 0x18A9, 0x18A9, 0x1920, 0x1922,
0x1927, 0x1928, 0x1932, 0x1932, 0x1939, 0x193B, 0x1A17, 0x1A18,
0x1B00, 0x1B03, 0x1B34, 0x1B34, 0x1B36, 0x1B3A, 0x1B3C, 0x1B3C,
0x1B42, 0x1B42, 0x1B6B, 0x1B73, 0x1DC0, 0x1DCA, 0x1DFE, 0x1DFF,
0x200B, 0x200F, 0x202A, 0x202E, 0x2060, 0x2063, 0x206A, 0x206F,
0x20D0, 0x20EF, 0x302A, 0x302F, 0x3099, 0x309A, 0xA806, 0xA806,
0xA80B, 0xA80B, 0xA825, 0xA826, 0xFB1E, 0xFB1E, 0xFE00, 0xFE0F,
0xFE20, 0xFE23, 0xFEFF, 0xFEFF, 0xFFF9, 0xFFFB, 0x10A01, 0x10A03,
0x10A05, 0x10A06, 0x10A0C, 0x10A0F, 0x10A38, 0x10A3A, 0x10A3F, 0x10A3F,
0x1D167, 0x1D169, 0x1D173, 0x1D182, 0x1D185, 0x1D18B, 0x1D1AA, 0x1D1AD,
0x1D242, 0x1D244, 0xE0001, 0xE0001, 0xE0020, 0xE007F, 0xE0100, 0xE01EF,
-1,
};
if (in_range(range1, c)) return 0;
static uint32_t range2[] = {
0x1100, 0x115F, 0x2329, 0x2329, 0x232A, 0x232A, 0x2E80, 0x303E,
0x3040, 0xA4CF, 0xAC00, 0xD7A3, 0xF900, 0xFAFF, 0xFE10, 0xFE19,
0xFE30, 0xFE6F, 0xFF00, 0xFF60, 0xFFE0, 0xFFE6, 0x1F000, 0x1F644,
0x20000, 0x2FFFD, 0x30000, 0x3FFFD, -1,
};
if (in_range(range2, c)) return 2;
return 1;
}
// Returns the number of columns needed to display a given
// string in a fixed-width font.
int str_width(char *p, int len) {
char *start = p;
int w = 0;
while (p - start < len) {
uint32_t c = decode_utf8(&p, p);
w += char_width(c);
}
return w;
}