blob: 34f4b2143c0c783d56ff52340db1b21bbf0179d2 (
plain) (
tree)
|
|
/* See LICENSE file for copyright and license details. */
#include "common.h"
int
libterminput_read_symbol__(int fd, struct input *input, struct libterminput_state *ctx)
{
unsigned char c, tc;
ssize_t r;
/* Get next byte from input */
if (ctx->stored_head != ctx->stored_tail) {
c = ((unsigned char *)ctx->stored)[ctx->stored_tail++];
if (ctx->stored_tail == ctx->stored_head)
ctx->stored_tail = ctx->stored_head = 0;
} else {
r = read(fd, ctx->stored, sizeof(ctx->stored));
if (r <= 0)
return (int)r;
c = (unsigned char)ctx->stored[0];
if (r > 1) {
ctx->stored_tail = 1U;
ctx->stored_head = (size_t)r;
}
}
/* Check if symbol is complete or can be completed, and split out modifier */
again:
if (ctx->n) {
/* Continuation of multibyte-character */
if ((c & 0xC0) != 0x80) {
/* Short multibyte-character: return short and store read byte from next input */
input->mods = ctx->mods;
ctx->partial[(unsigned char)ctx->npartial] = '\0';
ctx->n = 0;
ctx->npartial = 0;
ctx->mods = 0;
ctx->stored[ctx->stored_head++] = (char)c;
strcpy(input->symbol, ctx->partial);
return 1;
} else {
/* Store byte, and if done, return */
ctx->partial[(unsigned char)ctx->npartial++] = (char)c;
if (ctx->npartial == ctx->n) {
ctx->partial[(unsigned char)ctx->npartial] = '\0';
input->mods = ctx->mods;
ctx->npartial = 0;
ctx->mods = 0;
ctx->n = 0;
strcpy(input->symbol, ctx->partial);
return 1;
}
}
} else if (c == 033 && !*ctx->key) {
/* ESC at the beginning, save as a Meta/ESC */
ctx->meta += 1;
} else if (c == 0) {
/* CTRL on Space */
input->symbol[0] = ' ';
input->symbol[1] = '\0';
input->mods = ctx->mods | LIBTERMINPUT_CTRL;
ctx->mods = 0;
return 1;
} else if (c < (unsigned char)' ' && (char)c != '\t' && (char)c != '\b' && (char)c != '\n') {
/* CTRL on some some character key */
input->symbol[0] = (char)c + '@';
input->symbol[1] = '\0';
input->mods = ctx->mods | LIBTERMINPUT_CTRL;
ctx->mods = 0;
return 1;
} else if ((c & 0xC0) == 0xC0 && c != 0xFF) {
/* Beginning of multibyte-character */
ctx->n = 0;
for (tc = c; tc & 0x80; tc <<= 1)
ctx->n++;
if (ctx->n > 6) {
/* If overlong, return first byte a single-byte-character */
input->symbol[0] = (char)c;
input->symbol[1] = '\0';
input->mods = ctx->mods;
ctx->mods = 0;
return 1;
}
ctx->partial[0] = (char)c;
ctx->npartial = 1;
} else if (c & 0x80) {
/* 8th bit set to signify META */
c ^= 0x80;
ctx->mods |= LIBTERMINPUT_META;
goto again;
} else {
/* Single-byte-character */
input->symbol[0] = (char)c;
input->symbol[1] = '\0';
input->mods = ctx->mods;
ctx->mods = 0;
return 1;
}
/* Incomplete symbol */
input->symbol[0] = '\0';
input->mods = -1;
return 1;
}
|
