misc.c

/* See Copyright Notice in LICENSE.txt */

#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <sys/time.h>
#include <stdint.h>

#include "misc.h"

void die(const char *fmt, ...) {
    va_list ap;
    va_start(ap, fmt);
    printf("CRITICAL ERROR: ");
    vprintf(fmt, ap);
    printf("\n");
    va_end(ap);
    exit(1);
}

double time_delta(struct timeval *before, struct timeval *after) {
    double delta_seconds = after->tv_sec - before->tv_sec;
    double delta_milliseconds = (after->tv_usec - before->tv_usec) / 1000;

    if (delta_milliseconds < 0) {
        delta_milliseconds += 1000;
        delta_seconds--;
    }

    return delta_seconds * 1000 + delta_milliseconds;
}

void *xmalloc(size_t size) {
    void *ptr = calloc(1, size);
    if (!ptr) die("cannot malloc");
    return ptr;
}

// Copyright (c) 2008-2009 Bjoern Hoehrmann <bjoern@hoehrmann.de>
// See http://bjoern.hoehrmann.de/utf-8/decoder/dfa/ for details.
//
// Modified for info-beamer

static const uint8_t utf8d[] = {
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 00..1f
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 20..3f
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 40..5f
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 60..7f
  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, // 80..9f
  7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, // a0..bf
  8,8,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, // c0..df
  0xa,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x4,0x3,0x3, // e0..ef
  0xb,0x6,0x6,0x6,0x5,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8, // f0..ff
  0x0,0x1,0x2,0x3,0x5,0x8,0x7,0x1,0x1,0x1,0x4,0x6,0x1,0x1,0x1,0x1, // s0..s0
  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,1,1,0,1,0,1,1,1,1,1,1, // s1..s2
  1,2,1,1,1,1,1,2,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1, // s3..s4
  1,2,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,3,1,3,1,1,1,1,1,1, // s5..s6
  1,3,1,1,1,1,1,3,1,3,1,1,1,1,1,1,1,3,1,1,1,1,1,1,1,1,1,1,1,1,1,1, // s7..s8
};

#define UTF8_ACCEPT 0
#define UTF8_REJECT 1

uint32_t decode_utf8(uint32_t* state, uint32_t* codep, uint32_t byte) {
    uint32_t type = utf8d[byte];

    *codep = (*state != UTF8_ACCEPT) ?
        (byte & 0x3fu) | (*codep << 6) :
        (0xff >> type) & (byte);

    *state = utf8d[256 + *state*16 + type];
    return *state;
}

int check_utf8(const char* s) {
    uint32_t codepoint, state = 0;
    while (*s)
        decode_utf8(&state, &codepoint, *(uint8_t*)s++);
    return state == UTF8_ACCEPT;
}