mirrors/kitty
1
0
Fork 0
mirror of https://github.com/kovidgoyal/kitty synced 2026-07-25 09:48:09 +02:00
Code Issues Packages Projects Releases Wiki Activity

Make wcswidth useable in a streaming fashion

Browse Source
This commit is contained in:
Kovid Goyal
2020-09-21 13:31:24 +05:30
parent b5007ba276
commit 444080f320
6 changed files with 162 additions and 113 deletions
Download Patch File Download Diff File Expand all files Collapse all files

135
kitty/wcswidth.c Normal file
View File

@@ -0,0 +1,135 @@
/*
* wcswidth.c
* Copyright (C) 2020 Kovid Goyal <kovid at kovidgoyal.net>
*
* Distributed under terms of the GPL3 license.
*/
#include "wcwidth-std.h"
#include "wcswidth.h"
#include "unicode-data.h"
void
initialize_wcs_state(WCSState *state) {
zero_at_ptr(state);
}
static inline bool
is_flag_pair(char_type a, char_type b) {
return is_flag_codepoint(a) && is_flag_codepoint(b);
}
int
wcswidth_step(WCSState *state, const char_type ch) {
int ans = 0;
switch (state->parser_state) {
case IN_CSI: {
state->prev_width = 0;
if (0x40 <= ch && ch <= 0x7e) state->parser_state = NORMAL;
} break;
case IN_ST_TERMINATED: {
state->prev_width = 0;
if (ch == 0x9c || (ch == '\\' && state->prev_ch == 0x1b)) state->parser_state = NORMAL;
} break;
case FLAG_PAIR_STARTED: {
state->parser_state = NORMAL;
if (is_flag_pair(state->prev_ch, ch)) break;
} /* fallthrough */
case NORMAL: {
switch(ch) {
case 0x1b: {
state->prev_width = 0;
state->parser_state = IN_ESC;
} break;
case 0xfe0f: {
if (is_emoji_presentation_base(state->prev_ch) && state->prev_width == 1) {
ans += 1;
state->prev_width = 2;
} else state->prev_width = 0;
} break;
case 0xfe0e: {
if (is_emoji_presentation_base(state->prev_ch) && state->prev_width == 2) {
ans -= 1;
state->prev_width = 1;
} else state->prev_width = 0;
} break;
default: {
if (is_flag_codepoint(ch)) state->parser_state = FLAG_PAIR_STARTED;
int w = wcwidth_std(ch);
switch(w) {
case -1:
case 0:
state->prev_width = 0; break;
case 2:
state->prev_width = 2; break;
default:
state->prev_width = 1; break;
}
ans += state->prev_width;
} break;
} break; // switch(ch)
} break; // case NORMAL
case IN_ESC:
switch (ch) {
case '[':
state->parser_state = IN_CSI; break;
case 'P':
case ']':
case 'X':
case '^':
case '_':
state->parser_state = IN_ST_TERMINATED; break;
case 'D':
case 'E':
case 'H':
case 'M':
case 'N':
case 'O':
case 'Z':
case '6':
case '7':
case '8':
case '9':
case '=':
case '>':
case 'F':
case 'c':
case 'l':
case 'm':
case 'n':
case 'o':
case '|':
case '}':
case '~':
break;
default:
state->prev_ch = 0x1b;
state->prev_width = 0;
state->parser_state = NORMAL;
return wcswidth_step(state, ch);
} break;
}
state->prev_ch = ch;
return ans;
}
PyObject *
wcswidth_std(PyObject UNUSED *self, PyObject *str) {
if (PyUnicode_READY(str) != 0) return NULL;
int kind = PyUnicode_KIND(str);
void *data = PyUnicode_DATA(str);
Py_ssize_t len = PyUnicode_GET_LENGTH(str), i;
WCSState state;
initialize_wcs_state(&state);
size_t ans = 0;
for (i = 0; i < len; i++) {
char_type ch = PyUnicode_READ(kind, data, i);
ans += wcswidth_step(&state, ch);
}
return PyLong_FromSize_t(ans);
}