graphics/pdcurs34/pdcurses/pdc_util.c

/****************************************************************************
 * apps/graphics/pdcurses/util.c
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
 ****************************************************************************/

/****************************************************************************
 * Adapted from the original public domain pdcurses by Gregory Nutt
 ****************************************************************************/

/* Name: util
 *
 * Synopsis:
 *       char *unctrl(chtype c);
 *       void filter(void);
 *       void use_env(bool x);
 *       int delay_output(int ms);
 *
 *       int getcchar(const cchar_t *wcval, wchar_t *wch, attr_t *attrs,
 *                    short *color_pair, void *opts);
 *       int setcchar(cchar_t *wcval, const wchar_t *wch, const attr_t attrs,
 *                    short color_pair, const void *opts);
 *       wchar_t *wunctrl(cchar_t *wc);
 *
 *       int PDC_mbtowc(wchar_t *pwc, const char *s, size_t n);
 *       size_t PDC_mbstowcs(wchar_t *dest, const char *src, size_t n);
 *       size_t PDC_wcstombs(char *dest, const wchar_t *src, size_t n);
 *
 * Description:
 *       unctrl() expands the text portion of the chtype c into a
 *       printable string. Control characters are changed to the "^X"
 *       notation; others are passed through. wunctrl() is the wide-
 *       character version of the function.
 *
 *       filter() and use_env() are no-ops in PDCurses.
 *
 *       delay_output() inserts an ms millisecond pause in output.
 *
 *       getcchar() works in two modes: When wch is not NULL, it reads
 *       the cchar_t pointed to by wcval and stores the attributes in
 *       attrs, the color pair in color_pair, and the text in the
 *       wide-character string wch. When wch is NULL, getcchar() merely
 *       returns the number of wide characters in wcval. In either mode,
 *       the opts argument is unused.
 *
 *       setcchar constructs a cchar_t at wcval from the wide-character
 *       text at wch, the attributes in attr and the color pair in
 *       color_pair. The opts argument is unused.
 *
 *       Currently, the length returned by getcchar() is always 1 or 0.
 *       Similarly, setcchar() will only take the first wide character
 *       from wch, and ignore any others that it "should" take (i.e.,
 *       combining characters). Nor will it correctly handle any
 *       character outside the basic multilingual plane (UCS-2).
 *
 * Return Value:
 *       unctrl() and wunctrl() return NULL on failure. delay_output()
 *       always returns OK.
 *
 *       getcchar() returns the number of wide characters wcval points to
 *       when wch is NULL; when it's not, getcchar() returns OK or ERR.
 *
 *       setcchar() returns OK or ERR.
 *
 * Portability                                X/Open    BSD    SYS V
 *       unctrl                                  Y       Y       Y
 *       filter                                  Y       -      3.0
 *       use_env                                 Y       -      4.0
 *       delay_output                            Y       Y       Y
 *       getcchar                                Y
 *       setcchar                                Y
 *       wunctrl                                 Y
 *       PDC_mbtowc                              -       -       -
 *       PDC_mbstowcs                            -       -       -
 *       PDC_wcstombs                            -       -       -
 */

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include "curspriv.h"

#ifdef CONFIG_PDCURSES_WIDE
#  ifdef CONFIG_PDCURSES_FORCE_UTF8
#    include <string.h>
#  else
#    include <stdlib.h>
#  endif
#endif

/****************************************************************************
 * Public Functions
 ****************************************************************************/

char *unctrl(chtype c)
{
#ifdef CONFIG_PDCURSES_MULTITHREAD
  FAR struct pdc_context_s *ctx = PDC_ctx();
#else
  static char strbuf[3] = { 0, 0, 0 };
#endif

  chtype ic;

  PDC_LOG(("unctrl() - called\n"));

  ic = c & A_CHARTEXT;
  if (ic >= 0x20 && ic != 0x7f) /* normal characters */
    {
      strbuf[0] = (char)ic;
      strbuf[1] = '\0';
      return strbuf;
    }

  strbuf[0] = '^';              /* '^' prefix */

  if (ic == 0x7f)               /* 0x7f == DEL */
    {
      strbuf[1] = '?';
    }
  else                          /* other control */
    {
      strbuf[1] = (char)(ic + '@');
    }

  return strbuf;
}

void filter(void)
{
  PDC_LOG(("filter() - called\n"));
}

void use_env(bool x)
{
  PDC_LOG(("use_env() - called: x %d\n", x));
}

int delay_output(int ms)
{
  PDC_LOG(("delay_output() - called: ms %d\n", ms));

  return napms(ms);
}

#ifdef CONFIG_PDCURSES_WIDE
int getcchar(const cchar_t *wcval, wchar_t *wch, attr_t *attrs,
             short *color_pair, void *opts)
{
  if (!wcval)
    {
      return ERR;
    }

  if (wch)
    {
      if (!attrs || !color_pair)
        {
          return ERR;
        }

      *wch = (*wcval & A_CHARTEXT);
      *attrs = (*wcval & (A_ATTRIBUTES & ~A_COLOR));
      *color_pair = PAIR_NUMBER(*wcval & A_COLOR);

      if (*wch)
        {
          *++wch = L'\0';
        }

      return OK;
    }
  else
    {
      return ((*wcval & A_CHARTEXT) != L'\0');
    }
}

int setcchar(cchar_t *wcval, const wchar_t *wch, const attr_t attrs,
             short color_pair, const void *opts)
{
  if (!wcval || !wch)
    {
      return ERR;
    }

  *wcval = *wch | attrs | COLOR_PAIR(color_pair);
  return OK;
}

wchar_t *wunctrl(cchar_t *wc)
{
#ifdef CONFIG_PDCURSES_MULTITHREAD
  FAR struct pdc_context_s *ctx = PDC_ctx();
#else
  static wchar_t strbuf2[3] = { 0, 0, 0 };
#endif

  cchar_t ic;

  PDC_LOG(("wunctrl() - called\n"));

  ic = *wc & A_CHARTEXT;

  if (ic >= 0x20 && ic != 0x7f) /* normal characters */
    {
      strbuf2[0] = (wchar_t) ic;
      strbuf2[1] = L'\0';
      return strbuf;
    }

  strbuf2[0] = '^';              /* '^' prefix */

  if (ic == 0x7f)               /* 0x7f == DEL */
    {
      strbuf2[1] = '?';
    }
  else                          /* other control */
    {
      strbuf2[1] = (wchar_t) (ic + '@');
    }

  return strbuf2;
}

int PDC_mbtowc(wchar_t *pwc, const char *s, size_t n)
{
#ifdef CONFIG_PDCURSES_FORCE_UTF8
  wchar_t key;
  int i = -1;
  const unsigned char *string;

  if (!s || (n < 1))
    {
      return -1;
    }

  if (!*s)
    {
      return 0;
    }

  string = (const unsigned char *)s;

  key = string[0];

  /* Simplistic UTF-8 decoder -- only does the BMP, minimal validation */

  if (key & 0x80)
    {
      if ((key & 0xe0) == 0xc0)
        {
          if (1 < n)
            {
              key = ((key & 0x1f) << 6) | (string[1] & 0x3f);
              i = 2;
            }
        }
      else if ((key & 0xe0) == 0xe0)
        {
          if (2 < n)
            {
              key = ((key & 0x0f) << 12) | ((string[1] & 0x3f) << 6) |
                (string[2] & 0x3f);
              i = 3;
            }
        }
    }
  else
    {
      i = 1;
    }

  if (i)
    {
      *pwc = key;
    }

  return i;
#else
  return mbtowc(pwc, s, n);
#endif
}

size_t PDC_mbstowcs(wchar_t *dest, const char *src, size_t n)
{
#ifdef CONFIG_PDCURSES_FORCE_UTF8
  size_t len;
  size_t i = 0;

  if (!src || !dest)
    {
      return 0;
    }

  len = strlen(src);

  while (*src && i < n)
    {
      int retval = PDC_mbtowc(dest + i, src, len);

      if (retval < 1)
        {
          return -1;
        }

      src += retval;
      len -= retval;
      i++;
    }
#else
  size_t i = mbstowcs(dest, src, n);
#endif

  dest[i] = 0;
  return i;
}

size_t PDC_wcstombs(char *dest, const wchar_t *src, size_t n)
{
#ifdef CONFIG_PDCURSES_FORCE_UTF8
  size_t i = 0;

  if (!src || !dest)
    {
      return 0;
    }

  while (*src && i < n)
    {
      chtype code = *src++;

      if (code < 0x80)
        {
          dest[i] = code;
          i++;
        }
      else if (code < 0x800)
        {
          dest[i] = ((code & 0x07c0) >> 6) | 0xc0;
          dest[i + 1] = (code & 0x003f) | 0x80;
          i += 2;
        }
      else
        {
          dest[i] = ((code & 0xf000) >> 12) | 0xe0;
          dest[i + 1] = ((code & 0x0fc0) >> 6) | 0x80;
          dest[i + 2] = (code & 0x003f) | 0x80;
          i += 3;
        }
    }
#else
  size_t i = wcstombs(dest, src, n);
#endif

  dest[i] = '\0';
  return i;
}
#endif