/src/tmux/utf8.c

Source
/* $OpenBSD: utf8.c,v 1.76 2026/10/23 06:30:50 nicm Exp $ */

/*
 * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>

#include <ctype.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>

#include "compat.h"
#include "tmux.h"

struct utf8_width_item {
  wchar_t       wc;
  u_int       width;
  int       allocated;

  RB_ENTRY(utf8_width_item) entry;
};

static int
utf8_width_cache_cmp(struct utf8_width_item *uw1, struct utf8_width_item *uw2)
{
  if (uw1->wc < uw2->wc)
    return (-1);
  if (uw1->wc > uw2->wc)
    return (1);
  return (0);
}
RB_HEAD(utf8_width_cache, utf8_width_item);
RB_GENERATE_STATIC(utf8_width_cache, utf8_width_item, entry,
    utf8_width_cache_cmp);
static struct utf8_width_cache utf8_width_cache =
    RB_INITIALIZER(utf8_width_cache);

static struct utf8_width_item utf8_default_width_cache[] = {
  { .wc = 0x0270A, .width = 2 },
  { .wc = 0x0270B, .width = 2 },
  { .wc = 0x1F1E6, .width = 1 },
  { .wc = 0x1F1E7, .width = 1 },
  { .wc = 0x1F1E8, .width = 1 },
  { .wc = 0x1F1E9, .width = 1 },
  { .wc = 0x1F1EA, .width = 1 },
  { .wc = 0x1F1EB, .width = 1 },
  { .wc = 0x1F1EC, .width = 1 },
  { .wc = 0x1F1ED, .width = 1 },
  { .wc = 0x1F1EE, .width = 1 },
  { .wc = 0x1F1EF, .width = 1 },
  { .wc = 0x1F1F0, .width = 1 },
  { .wc = 0x1F1F1, .width = 1 },
  { .wc = 0x1F1F2, .width = 1 },
  { .wc = 0x1F1F3, .width = 1 },
  { .wc = 0x1F1F4, .width = 1 },
  { .wc = 0x1F1F5, .width = 1 },
  { .wc = 0x1F1F6, .width = 1 },
  { .wc = 0x1F1F7, .width = 1 },
  { .wc = 0x1F1F8, .width = 1 },
  { .wc = 0x1F1F9, .width = 1 },
  { .wc = 0x1F1FA, .width = 1 },
  { .wc = 0x1F1FB, .width = 1 },
  { .wc = 0x1F1FC, .width = 1 },
  { .wc = 0x1F1FD, .width = 1 },
  { .wc = 0x1F1FE, .width = 1 },
  { .wc = 0x1F1FF, .width = 1 },
  { .wc = 0x1F385, .width = 2 },
  { .wc = 0x1F3C2, .width = 2 },
  { .wc = 0x1F3C3, .width = 2 },
  { .wc = 0x1F3C4, .width = 2 },
  { .wc = 0x1F3C7, .width = 2 },
  { .wc = 0x1F3CA, .width = 2 },
  { .wc = 0x1F3CB, .width = 2 },
  { .wc = 0x1F3CC, .width = 2 },
  { .wc = 0x1F3FB, .width = 2 },
  { .wc = 0x1F3FC, .width = 2 },
  { .wc = 0x1F3FD, .width = 2 },
  { .wc = 0x1F3FE, .width = 2 },
  { .wc = 0x1F3FF, .width = 2 },
  { .wc = 0x1F442, .width = 2 },
  { .wc = 0x1F443, .width = 2 },
  { .wc = 0x1F446, .width = 2 },
  { .wc = 0x1F447, .width = 2 },
  { .wc = 0x1F448, .width = 2 },
  { .wc = 0x1F449, .width = 2 },
  { .wc = 0x1F44A, .width = 2 },
  { .wc = 0x1F44B, .width = 2 },
  { .wc = 0x1F44C, .width = 2 },
  { .wc = 0x1F44D, .width = 2 },
  { .wc = 0x1F44E, .width = 2 },
  { .wc = 0x1F44F, .width = 2 },
  { .wc = 0x1F450, .width = 2 },
  { .wc = 0x1F466, .width = 2 },
  { .wc = 0x1F467, .width = 2 },
  { .wc = 0x1F468, .width = 2 },
  { .wc = 0x1F469, .width = 2 },
  { .wc = 0x1F46B, .width = 2 },
  { .wc = 0x1F46C, .width = 2 },
  { .wc = 0x1F46D, .width = 2 },
  { .wc = 0x1F46E, .width = 2 },
  { .wc = 0x1F470, .width = 2 },
  { .wc = 0x1F471, .width = 2 },
  { .wc = 0x1F472, .width = 2 },
  { .wc = 0x1F473, .width = 2 },
  { .wc = 0x1F474, .width = 2 },
  { .wc = 0x1F475, .width = 2 },
  { .wc = 0x1F476, .width = 2 },
  { .wc = 0x1F477, .width = 2 },
  { .wc = 0x1F478, .width = 2 },
  { .wc = 0x1F47C, .width = 2 },
  { .wc = 0x1F481, .width = 2 },
  { .wc = 0x1F482, .width = 2 },
  { .wc = 0x1F483, .width = 2 },
  { .wc = 0x1F485, .width = 2 },
  { .wc = 0x1F486, .width = 2 },
  { .wc = 0x1F487, .width = 2 },
  { .wc = 0x1F48F, .width = 2 },
  { .wc = 0x1F491, .width = 2 },
  { .wc = 0x1F4AA, .width = 2 },
  { .wc = 0x1F574, .width = 2 },
  { .wc = 0x1F575, .width = 2 },
  { .wc = 0x1F57A, .width = 2 },
  { .wc = 0x1F590, .width = 2 },
  { .wc = 0x1F595, .width = 2 },
  { .wc = 0x1F596, .width = 2 },
  { .wc = 0x1F645, .width = 2 },
  { .wc = 0x1F646, .width = 2 },
  { .wc = 0x1F647, .width = 2 },
  { .wc = 0x1F64B, .width = 2 },
  { .wc = 0x1F64C, .width = 2 },
  { .wc = 0x1F64D, .width = 2 },
  { .wc = 0x1F64E, .width = 2 },
  { .wc = 0x1F64F, .width = 2 },
  { .wc = 0x1F6A3, .width = 2 },
  { .wc = 0x1F6B4, .width = 2 },
  { .wc = 0x1F6B5, .width = 2 },
  { .wc = 0x1F6B6, .width = 2 },
  { .wc = 0x1F6C0, .width = 2 },
  { .wc = 0x1F6CC, .width = 2 },
  { .wc = 0x1F90C, .width = 2 },
  { .wc = 0x1F90F, .width = 2 },
  { .wc = 0x1F918, .width = 2 },
  { .wc = 0x1F919, .width = 2 },
  { .wc = 0x1F91A, .width = 2 },
  { .wc = 0x1F91B, .width = 2 },
  { .wc = 0x1F91C, .width = 2 },
  { .wc = 0x1F91D, .width = 2 },
  { .wc = 0x1F91E, .width = 2 },
  { .wc = 0x1F91F, .width = 2 },
  { .wc = 0x1F926, .width = 2 },
  { .wc = 0x1F930, .width = 2 },
  { .wc = 0x1F931, .width = 2 },
  { .wc = 0x1F932, .width = 2 },
  { .wc = 0x1F933, .width = 2 },
  { .wc = 0x1F934, .width = 2 },
  { .wc = 0x1F935, .width = 2 },
  { .wc = 0x1F936, .width = 2 },
  { .wc = 0x1F937, .width = 2 },
  { .wc = 0x1F938, .width = 2 },
  { .wc = 0x1F939, .width = 2 },
  { .wc = 0x1F93D, .width = 2 },
  { .wc = 0x1F93E, .width = 2 },
  { .wc = 0x1F977, .width = 2 },
  { .wc = 0x1F9B5, .width = 2 },
  { .wc = 0x1F9B6, .width = 2 },
  { .wc = 0x1F9B8, .width = 2 },
  { .wc = 0x1F9B9, .width = 2 },
  { .wc = 0x1F9BB, .width = 2 },
  { .wc = 0x1F9CD, .width = 2 },
  { .wc = 0x1F9CE, .width = 2 },
  { .wc = 0x1F9CF, .width = 2 },
  { .wc = 0x1F9D1, .width = 2 },
  { .wc = 0x1F9D2, .width = 2 },
  { .wc = 0x1F9D3, .width = 2 },
  { .wc = 0x1F9D4, .width = 2 },
  { .wc = 0x1F9D5, .width = 2 },
  { .wc = 0x1F9D6, .width = 2 },
  { .wc = 0x1F9D7, .width = 2 },
  { .wc = 0x1F9D8, .width = 2 },
  { .wc = 0x1F9D9, .width = 2 },
  { .wc = 0x1F9DA, .width = 2 },
  { .wc = 0x1F9DB, .width = 2 },
  { .wc = 0x1F9DC, .width = 2 },
  { .wc = 0x1F9DD, .width = 2 },
  { .wc = 0x1FAC3, .width = 2 },
  { .wc = 0x1FAC4, .width = 2 },
  { .wc = 0x1FAC5, .width = 2 },
  { .wc = 0x1FAF0, .width = 2 },
  { .wc = 0x1FAF1, .width = 2 },
  { .wc = 0x1FAF2, .width = 2 },
  { .wc = 0x1FAF3, .width = 2 },
  { .wc = 0x1FAF4, .width = 2 },
  { .wc = 0x1FAF5, .width = 2 },
  { .wc = 0x1FAF6, .width = 2 },
  { .wc = 0x1FAF7, .width = 2 },
  { .wc = 0x1FAF8, .width = 2 }
};

struct utf8_item {
  RB_ENTRY(utf8_item) index_entry;
  u_int     index;

  RB_ENTRY(utf8_item) data_entry;
  char      data[UTF8_SIZE];
  u_char      size;
};

static int
utf8_data_cmp(struct utf8_item *ui1, struct utf8_item *ui2)
{
  if (ui1->size < ui2->size)
    return (-1);
  if (ui1->size > ui2->size)
    return (1);
  return (memcmp(ui1->data, ui2->data, ui1->size));
}
RB_HEAD(utf8_data_tree, utf8_item);
RB_GENERATE_STATIC(utf8_data_tree, utf8_item, data_entry, utf8_data_cmp);
static struct utf8_data_tree utf8_data_tree = RB_INITIALIZER(utf8_data_tree);

static int
utf8_index_cmp(struct utf8_item *ui1, struct utf8_item *ui2)
{
  if (ui1->index < ui2->index)
    return (-1);
  if (ui1->index > ui2->index)
    return (1);
  return (0);
}
RB_HEAD(utf8_index_tree, utf8_item);
RB_GENERATE_STATIC(utf8_index_tree, utf8_item, index_entry, utf8_index_cmp);
static struct utf8_index_tree utf8_index_tree = RB_INITIALIZER(utf8_index_tree);

static int  utf8_no_width;
static u_int  utf8_next_index;

#define UTF8_GET_SIZE(uc) (((uc) >> 24) & 0x1f)
#define UTF8_GET_WIDTH(uc) (((uc) >> 29) - 1)

#define UTF8_SET_SIZE(size) (((utf8_char)(size)) << 24)
#define UTF8_SET_WIDTH(width) ((((utf8_char)(width)) + 1) << 29)

/* Get a UTF-8 item from data. */
static struct utf8_item *
utf8_item_by_data(const u_char *data, size_t size)
{
  struct utf8_item  ui;

  memcpy(ui.data, data, size);
  ui.size = size;

  return (RB_FIND(utf8_data_tree, &utf8_data_tree, &ui));
}

/* Get a UTF-8 item from data. */
static struct utf8_item *
utf8_item_by_index(u_int index)
{
  struct utf8_item  ui;

  ui.index = index;

  return (RB_FIND(utf8_index_tree, &utf8_index_tree, &ui));
}

/* Find a codepoint in the cache. */
static struct utf8_width_item *
utf8_find_in_width_cache(wchar_t wc)
{
  struct utf8_width_item  uw;

  uw.wc = wc;
  return RB_FIND(utf8_width_cache, &utf8_width_cache, &uw);
}

/* Add to width cache. */
static void
utf8_insert_width_cache(wchar_t wc, u_int width)
{
  struct utf8_width_item  *uw, *old;

  log_debug("Unicode width cache: %08X=%u", (u_int)wc, width);

  uw = xcalloc(1, sizeof *uw);
  uw->wc = wc;
  uw->width = width;
  uw->allocated = 1;

  old = RB_INSERT(utf8_width_cache, &utf8_width_cache, uw);
  if (old != NULL) {
    RB_REMOVE(utf8_width_cache, &utf8_width_cache, old);
    if (old->allocated)
      free(old);
    RB_INSERT(utf8_width_cache, &utf8_width_cache, uw);
  }
}

/* Parse a single codepoint option. */
static void
utf8_add_to_width_cache(const char *s)
{
  char      *copy, *cp, *endptr;
  u_int      width;
  const char    *errstr;
  struct utf8_data  *ud;
  wchar_t      wc, wc_start, wc_end;
  unsigned long long   n;

  copy = xstrdup(s);
  if ((cp = strchr(copy, '=')) == NULL) {
    free(copy);
    return;
  }
  *cp++ = '\0';

  width = strtonum(cp, 0, 2, &errstr);
  if (errstr != NULL) {
    free(copy);
    return;
  }

  if (strncmp(copy, "U+", 2) == 0) {
    errno = 0;
    n = strtoull(copy + 2, &endptr, 16);
    if (copy[2] == '\0' ||
        n == 0 ||
        n > WCHAR_MAX ||
        (errno == ERANGE && n == ULLONG_MAX)) {
      free(copy);
      return;
    }
    wc_start = n;
    if (*endptr == '-') {
      endptr++;
      if (strncmp(endptr, "U+", 2) != 0) {
        free(copy);
        return;
      }
      errno = 0;
      n = strtoull(endptr + 2, &endptr, 16);
      if (*endptr != '\0' ||
          n == 0 ||
          n > WCHAR_MAX ||
          (errno == ERANGE && n == ULLONG_MAX) ||
          (wchar_t)n < wc_start) {
        free(copy);
        return;
      }
      wc_end = n;
    } else {
      if (*endptr != '\0') {
        free(copy);
        return;
      }
      wc_end = wc_start;
    }

    wc = wc_start;
    for (;;) {
      utf8_insert_width_cache(wc, width);
      if (wc == wc_end)
        break;
      wc++;
    }
  } else {
    utf8_no_width = 1;
    ud = utf8_fromcstr(copy);
    utf8_no_width = 0;
    if (ud[0].size == 0 || ud[1].size != 0) {
      free(ud);
      free(copy);
      return;
    }
#ifdef HAVE_UTF8PROC
    if (utf8proc_mbtowc(&wc, ud[0].data, ud[0].size) <= 0) {
#else
    if (mbtowc(&wc, ud[0].data, ud[0].size) <= 0) {
#endif
      free(ud);
      free(copy);
      return;
    }
    free(ud);

    utf8_insert_width_cache(wc, width);
  }

  free(copy);
}

/* Rebuild cache of widths. */
void
utf8_update_width_cache(void)
{
  struct utf8_width_item    *uw, *uw1;
  struct options_entry    *o;
  struct options_array_item *a;
  u_int        i;

  RB_FOREACH_SAFE (uw, utf8_width_cache, &utf8_width_cache, uw1) {
    RB_REMOVE(utf8_width_cache, &utf8_width_cache, uw);
    if (uw->allocated)
      free(uw);
  }

  for (i = 0; i < nitems(utf8_default_width_cache); i++) {
    RB_INSERT(utf8_width_cache, &utf8_width_cache,
        &utf8_default_width_cache[i]);
  }

  o = options_get(global_options, "codepoint-widths");
  a = options_array_first(o);
  while (a != NULL) {
    utf8_add_to_width_cache(options_array_item_value(a)->string);
    a = options_array_next(a);
  }
}

/* Add a UTF-8 item. */
static int
utf8_put_item(const u_char *data, size_t size, u_int *index)
{
  struct utf8_item  *ui;

  ui = utf8_item_by_data(data, size);
  if (ui != NULL) {
    *index = ui->index;
    log_debug("%s: found %.*s = %u", __func__, (int)size, data,
        *index);
    return (0);
  }

  if (utf8_next_index == 0xffffff + 1)
    return (-1);

  ui = xcalloc(1, sizeof *ui);
  ui->index = utf8_next_index++;
  RB_INSERT(utf8_index_tree, &utf8_index_tree, ui);

  memcpy(ui->data, data, size);
  ui->size = size;
  RB_INSERT(utf8_data_tree, &utf8_data_tree, ui);

  *index = ui->index;
  log_debug("%s: added %.*s = %u", __func__, (int)size, data, *index);
  return (0);
}

/* Get UTF-8 character from data. */
enum utf8_state
utf8_from_data(const struct utf8_data *ud, utf8_char *uc)
{
  u_int index;

  if (ud->width > 2)
    fatalx("invalid UTF-8 width: %u", ud->width);

  if (ud->size > UTF8_SIZE)
    goto fail;
  if (ud->size <= 3) {
    index = (((utf8_char)ud->data[2] << 16)|
        ((utf8_char)ud->data[1] << 8)|
        ((utf8_char)ud->data[0]));
  } else if (utf8_put_item(ud->data, ud->size, &index) != 0)
    goto fail;
  *uc = UTF8_SET_SIZE(ud->size)|UTF8_SET_WIDTH(ud->width)|index;
  log_debug("%s: (%d %d %.*s) -> %08x", __func__, ud->width, ud->size,
      (int)ud->size, ud->data, *uc);
  return (UTF8_DONE);

fail:
  if (ud->width == 0)
    *uc = UTF8_SET_SIZE(0)|UTF8_SET_WIDTH(0);
  else if (ud->width == 1)
    *uc = UTF8_SET_SIZE(1)|UTF8_SET_WIDTH(1)|0x20;
  else
    *uc = UTF8_SET_SIZE(1)|UTF8_SET_WIDTH(1)|0x2020;
  return (UTF8_ERROR);
}

/* Get UTF-8 data from character. */
void
utf8_to_data(utf8_char uc, struct utf8_data *ud)
{
  struct utf8_item  *ui;
  u_int      index;

  memset(ud, 0, sizeof *ud);
  ud->size = ud->have = UTF8_GET_SIZE(uc);
  ud->width = UTF8_GET_WIDTH(uc);

  if (ud->size <= 3) {
    ud->data[2] = (uc >> 16);
    ud->data[1] = ((uc >> 8) & 0xff);
    ud->data[0] = (uc & 0xff);
  } else {
    index = (uc & 0xffffff);
    if ((ui = utf8_item_by_index(index)) == NULL)
      memset(ud->data, ' ', ud->size);
    else
      memcpy(ud->data, ui->data, ud->size);
  }

  log_debug("%s: %08x -> (%d %d %.*s)", __func__, uc, ud->width, ud->size,
      (int)ud->size, ud->data);
}

/* Get UTF-8 character from a single ASCII character. */
u_int
utf8_build_one(u_char ch)
{
  return (UTF8_SET_SIZE(1)|UTF8_SET_WIDTH(1)|ch);
}

/* Set a single character. */
void
utf8_set(struct utf8_data *ud, u_char ch)
{
  static const struct utf8_data empty = { { 0 }, 1, 1, 1 };

  memcpy(ud, &empty, sizeof *ud);
  *ud->data = ch;
}

/* Copy UTF-8 character. */
void
utf8_copy(struct utf8_data *to, const struct utf8_data *from)
{
  u_int i;

  memcpy(to, from, sizeof *to);

  for (i = to->size; i < sizeof to->data; i++)
    to->data[i] = '\0';
}

/* Get width of Unicode character. */
static enum utf8_state
utf8_width(struct utf8_data *ud, int *width)
{
  struct utf8_width_item  *uw;
  wchar_t      wc;

  if (utf8_towc(ud, &wc) != UTF8_DONE)
    return (UTF8_ERROR);
  uw = utf8_find_in_width_cache(wc);
  if (uw != NULL) {
    *width = uw->width;
    log_debug("cached width for %08X is %d", (u_int)wc, *width);
    return (UTF8_DONE);
  }
#ifdef HAVE_UTF8PROC
  *width = utf8proc_wcwidth(wc);
  log_debug("utf8proc_wcwidth(%05X) returned %d", (u_int)wc, *width);
#else
  *width = wcwidth(wc);
  log_debug("wcwidth(%05X) returned %d", (u_int)wc, *width);
  if (*width < 0) {
    /*
     * C1 control characters are nonprintable, so they are always
     * zero width.
     */
    *width = (wc >= 0x80 && wc <= 0x9f) ? 0 : 1;
  }
#endif
  if (*width >= 0 && *width <= 0xff)
    return (UTF8_DONE);
  return (UTF8_ERROR);
}

/* Convert UTF-8 character to wide character. */
enum utf8_state
utf8_towc(const struct utf8_data *ud, wchar_t *wc)
{
#ifdef HAVE_UTF8PROC
  switch (utf8proc_mbtowc(wc, ud->data, ud->size)) {
#else
  switch (mbtowc(wc, ud->data, ud->size)) {
#endif
  case -1:
    log_debug("UTF-8 %.*s, mbtowc() %d", (int)ud->size, ud->data,
        errno);
    mbtowc(NULL, NULL, MB_CUR_MAX);
    return (UTF8_ERROR);
  case 0:
    return (UTF8_ERROR);
  }
  log_debug("UTF-8 %.*s is U+%06X", (int)ud->size, ud->data, (u_int)*wc);
  return (UTF8_DONE);
}

/* Check for a Unicode whitespace character. */
int
utf8_has_whitespace(const struct utf8_data *ud)
{
  struct utf8_data tmp;
  wchar_t    wc;
  u_int    offset = 0, size;
  u_char     ch;

  while (offset < ud->size) {
    ch = ud->data[offset];
    if (ch < 0x80) {
      wc = ch;
      size = 1;
    } else {
      if (ch >= 0xc2 && ch <= 0xdf)
        size = 2;
      else if (ch >= 0xe0 && ch <= 0xef)
        size = 3;
      else if (ch >= 0xf0 && ch <= 0xf4)
        size = 4;
      else
        return (0);
      if (size > ud->size - offset)
        return (0);

      memset(&tmp, 0, sizeof tmp);
      memcpy(tmp.data, ud->data + offset, size);
      tmp.size = tmp.have = size;
      if (utf8_towc(&tmp, &wc) != UTF8_DONE)
        return (0);
    }
    offset += size;

    switch (wc) {
    case 0x0009:
    case 0x000A:
    case 0x000B:
    case 0x000C:
    case 0x000D:
    case 0x0020:
    case 0x0085:
    case 0x00A0:
    case 0x1680:
    case 0x2000:
    case 0x2001:
    case 0x2002:
    case 0x2003:
    case 0x2004:
    case 0x2005:
    case 0x2006:
    case 0x2007:
    case 0x2008:
    case 0x2009:
    case 0x200A:
    case 0x2028:
    case 0x2029:
    case 0x202F:
    case 0x205F:
    case 0x3000:
      return (1);
    }
  }
  return (0);
}

/* Convert wide character to UTF-8 character. */
enum utf8_state
utf8_fromwc(wchar_t wc, struct utf8_data *ud)
{
  int size, width;

  memset(ud, 0, sizeof *ud);

#ifdef HAVE_UTF8PROC
  size = utf8proc_wctomb(ud->data, wc);
#else
  size = wctomb(ud->data, wc);
#endif
  if (size < 0) {
    log_debug("UTF-8 %d, wctomb() %d", wc, errno);
    wctomb(NULL, 0);
    return (UTF8_ERROR);
  }
  if (size == 0)
    return (UTF8_ERROR);
  ud->size = ud->have = size;
  if (utf8_width(ud, &width) == UTF8_DONE) {
    ud->width = width;
    return (UTF8_DONE);
  }
  return (UTF8_ERROR);
}

/*
 * Open UTF-8 sequence.
 *
 * 11000010-11011111 C2-DF start of 2-byte sequence
 * 11100000-11101111 E0-EF start of 3-byte sequence
 * 11110000-11110100 F0-F4 start of 4-byte sequence
 */
enum utf8_state
utf8_open(struct utf8_data *ud, u_char ch)
{
  memset(ud, 0, sizeof *ud);
  if (ch >= 0xc2 && ch <= 0xdf)
    ud->size = 2;
  else if (ch >= 0xe0 && ch <= 0xef)
    ud->size = 3;
  else if (ch >= 0xf0 && ch <= 0xf4)
    ud->size = 4;
  else
    return (UTF8_ERROR);
  utf8_append(ud, ch);
  return (UTF8_MORE);
}

/* Append character to UTF-8, closing if finished. */
enum utf8_state
utf8_append(struct utf8_data *ud, u_char ch)
{
  int width;

  if (ud->have >= ud->size)
    fatalx("UTF-8 character overflow");
  if (ud->size > sizeof ud->data)
    fatalx("UTF-8 character size too large");

  if (ud->have != 0 && (ch & 0xc0) != 0x80)
    ud->width = 0xff;

  ud->data[ud->have++] = ch;
  if (ud->have != ud->size)
    return (UTF8_MORE);

  if (!utf8_no_width) {
    if (ud->width == 0xff)
      return (UTF8_ERROR);
    if (utf8_width(ud, &width) != UTF8_DONE)
      return (UTF8_ERROR);
    ud->width = width;
  }

  return (UTF8_DONE);
}

/*
 * Encode len characters from src into dst, which is guaranteed to have four
 * bytes available for each character from src (for \abc or UTF-8) plus space
 * for \0.
 */
size_t
utf8_strvis(char *dst, const char *src, size_t len, int flag)
{
  struct utf8_data   ud;
  const char    *start = dst, *end = src + len;
  enum utf8_state    more;
  size_t       i;

  while (src < end) {
    if ((more = utf8_open(&ud, *src)) == UTF8_MORE) {
      while (++src < end && more == UTF8_MORE)
        more = utf8_append(&ud, *src);
      if (more == UTF8_DONE) {
        /* UTF-8 character finished. */
        for (i = 0; i < ud.size; i++)
          *dst++ = ud.data[i];
        continue;
      }
      /* Not a complete, valid UTF-8 character. */
      src -= ud.have;
    }
    if ((flag & VIS_DQ) && src[0] == '$' && src < end - 1) {
      if (isalpha((u_char)src[1]) ||
          src[1] == '_' ||
          src[1] == '{')
        *dst++ = '\\';
      *dst++ = '$';
    } else if (src < end - 1)
      dst = vis(dst, src[0], flag, src[1]);
    else if (src < end)
      dst = vis(dst, src[0], flag, '\0');
    src++;
  }
  *dst = '\0';
  return (dst - start);
}

/* Same as utf8_strvis but allocate the buffer. */
size_t
utf8_stravis(char **dst, const char *src, int flag)
{
  char  *buf;
  size_t   len;

  buf = xreallocarray(NULL, 4, strlen(src) + 1);
  len = utf8_strvis(buf, src, strlen(src), flag);

  *dst = xrealloc(buf, len + 1);
  return (len);
}

/* Same as utf8_strvis but allocate the buffer. */
size_t
utf8_stravisx(char **dst, const char *src, size_t srclen, int flag)
{
  char  *buf;
  size_t   len;

  buf = xreallocarray(NULL, 4, srclen + 1);
  len = utf8_strvis(buf, src, srclen, flag);

  *dst = xrealloc(buf, len + 1);
  return (len);
}

/* Does this string contain anything that isn't valid UTF-8? */
int
utf8_isvalid(const char *s)
{
  struct utf8_data ud;
  const char  *end;
  enum utf8_state  more;

  end = s + strlen(s);
  while (s < end) {
    if ((more = utf8_open(&ud, *s)) == UTF8_MORE) {
      while (++s < end && more == UTF8_MORE)
        more = utf8_append(&ud, *s);
      if (more == UTF8_DONE)
        continue;
      return (0);
    }
    if (*s != '\t' && *s != '\n' && (*s < 0x20 || *s > 0x7e))
      return (0);
    s++;
  }
  return (1);
}

/*
 * Sanitize a string, changing any UTF-8 characters to '_'. Caller should free
 * the returned string. Anything not valid printable ASCII or UTF-8 is
 * stripped.
 */
char *
utf8_sanitize(const char *src)
{
  char    *dst = NULL;
  size_t     n = 0;
  enum utf8_state  more;
  struct utf8_data ud;
  u_int    i;

  while (*src != '\0') {
    dst = xreallocarray(dst, n + 1, sizeof *dst);
    if ((more = utf8_open(&ud, *src)) == UTF8_MORE) {
      while (*++src != '\0' && more == UTF8_MORE)
        more = utf8_append(&ud, *src);
      if (more == UTF8_DONE) {
        dst = xreallocarray(dst, n + ud.width,
            sizeof *dst);
        for (i = 0; i < ud.width; i++)
          dst[n++] = '_';
        continue;
      }
      src -= ud.have;
    }
    if (*src > 0x1f && *src < 0x7f)
      dst[n++] = *src;
    else
      dst[n++] = '_';
    src++;
  }
  dst = xreallocarray(dst, n + 1, sizeof *dst);
  dst[n] = '\0';
  return (dst);
}

/* Get UTF-8 buffer length. */
size_t
utf8_strlen(const struct utf8_data *s)
{
  size_t  i;

  for (i = 0; s[i].size != 0; i++)
    /* nothing */;
  return (i);
}

/* Get UTF-8 string width. */
u_int
utf8_strwidth(const struct utf8_data *s, ssize_t n)
{
  ssize_t i;
  u_int width = 0;

  for (i = 0; s[i].size != 0; i++) {
    if (n != -1 && n == i)
      break;
    width += s[i].width;
  }
  return (width);
}

/*
 * Convert a string into a buffer of UTF-8 characters. Terminated by size == 0.
 * Caller frees.
 */
struct utf8_data *
utf8_fromcstr(const char *src)
{
  struct utf8_data  *dst = NULL;
  size_t       n = 0;
  enum utf8_state    more;

  while (*src != '\0') {
    dst = xreallocarray(dst, n + 1, sizeof *dst);
    if ((more = utf8_open(&dst[n], *src)) == UTF8_MORE) {
      while (*++src != '\0' && more == UTF8_MORE)
        more = utf8_append(&dst[n], *src);
      if (more == UTF8_DONE) {
        n++;
        continue;
      }
      src -= dst[n].have;
    }
    utf8_set(&dst[n], *src);
    n++;
    src++;
  }
  dst = xreallocarray(dst, n + 1, sizeof *dst);
  dst[n].size = 0;
  return (dst);
}

/* Convert from a buffer of UTF-8 characters into a string. Caller frees. */
char *
utf8_tocstr(struct utf8_data *src)
{
  char  *dst = NULL;
  size_t   n = 0;

  for(; src->size != 0; src++) {
    dst = xreallocarray(dst, n + src->size, 1);
    memcpy(dst + n, src->data, src->size);
    n += src->size;
  }
  dst = xreallocarray(dst, n + 1, 1);
  dst[n] = '\0';
  return (dst);
}

/* Get width of UTF-8 string. */
u_int
utf8_cstrwidth(const char *s)
{
  struct utf8_data  tmp;
  u_int     width;
  enum utf8_state   more;

  width = 0;
  while (*s != '\0') {
    if ((more = utf8_open(&tmp, *s)) == UTF8_MORE) {
      while (*++s != '\0' && more == UTF8_MORE)
        more = utf8_append(&tmp, *s);
      if (more == UTF8_DONE) {
        width += tmp.width;
        continue;
      }
      s -= tmp.have;
    }
    if (*s > 0x1f && *s != 0x7f)
      width++;
    s++;
  }
  return (width);
}

/* Pad UTF-8 string to width on the left. Caller frees. */
char *
utf8_padcstr(const char *s, u_int width)
{
  size_t   slen;
  char  *out;
  u_int  n, i;

  n = utf8_cstrwidth(s);
  if (n >= width)
    return (xstrdup(s));

  slen = strlen(s);
  out = xmalloc(slen + 1 + (width - n));
  memcpy(out, s, slen);
  for (i = n; i < width; i++)
    out[slen++] = ' ';
  out[slen] = '\0';
  return (out);
}

/* Pad UTF-8 string to width on the right. Caller frees. */
char *
utf8_rpadcstr(const char *s, u_int width)
{
  size_t   slen;
  char  *out;
  u_int  n, i;

  n = utf8_cstrwidth(s);
  if (n >= width)
    return (xstrdup(s));

  slen = strlen(s);
  out = xmalloc(slen + 1 + (width - n));
  for (i = 0; i < width - n; i++)
    out[i] = ' ';
  memcpy(out + i, s, slen);
  out[i + slen] = '\0';
  return (out);
}

int
utf8_cstrhas(const char *s, const struct utf8_data *ud)
{
  struct utf8_data  *copy, *loop;
  int      found = 0;

  copy = utf8_fromcstr(s);
  for (loop = copy; loop->size != 0; loop++) {
    if (loop->size != ud->size)
      continue;
    if (memcmp(loop->data, ud->data, loop->size) == 0) {
      found = 1;
      break;
    }
  }
  free(copy);

  return (found);
}

Coverage Report

Created: 2026-10-28 06:08