regex_internal.c

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	      }
	    else
	      memcpy (pstr->mbs + byte_idx, p, mbclen);

	    if (BE (pstr->offsets_needed != 0, 0))
	      {
		size_t i;
		for (i = 0; i < mbclen; ++i)
		  pstr->offsets[byte_idx + i] = src_idx + i;
	      }
	    src_idx += mbclen;

	    pstr->wcs[byte_idx++] = wcu;
	    /* Write paddings.  */
	    for (remain_len = byte_idx + mbclen - 1; byte_idx < remain_len ;)
	      pstr->wcs[byte_idx++] = WEOF;
	  }
	else if (mbclen == (size_t) -1 || mbclen == 0)
	  {
	    /* It is an invalid character or '\0'.  Just use the byte.  */
	    int ch = pstr->raw_mbs[pstr->raw_mbs_idx + src_idx];

	    if (BE (pstr->trans != NULL, 0))
	      ch = pstr->trans [ch];
	    pstr->mbs[byte_idx] = ch;

	    if (BE (pstr->offsets_needed != 0, 0))
	      pstr->offsets[byte_idx] = src_idx;
	    ++src_idx;

	    /* And also cast it to wide char.  */
	    pstr->wcs[byte_idx++] = (wchar_t) ch;
	    if (BE (mbclen == (size_t) -1, 0))
	      pstr->cur_state = prev_st;
	  }
	else
	  {
	    /* The buffer doesn't have enough space, finish to build.  */
	    pstr->cur_state = prev_st;
	    break;
	  }
      }
  pstr->valid_len = byte_idx;
  pstr->valid_raw_len = src_idx;
  return REG_NOERROR;
}

/* Skip characters until the index becomes greater than NEW_RAW_IDX.
   Return the index.  */

static Idx
internal_function
re_string_skip_chars (re_string_t *pstr, Idx new_raw_idx, wint_t *last_wc)
{
  mbstate_t prev_st;
  Idx rawbuf_idx;
  size_t mbclen;
  wint_t wc = WEOF;

  /* Skip the characters which are not necessary to check.  */
  for (rawbuf_idx = pstr->raw_mbs_idx + pstr->valid_raw_len;
       rawbuf_idx < new_raw_idx;)
    {
      wchar_t wc2;
      Idx remain_len;
      remain_len = pstr->len - rawbuf_idx;
      prev_st = pstr->cur_state;
      mbclen = mbrtowc (&wc2, (const char *) pstr->raw_mbs + rawbuf_idx,
			remain_len, &pstr->cur_state);
      if (BE (mbclen == (size_t) -2 || mbclen == (size_t) -1 || mbclen == 0, 0))
	{
	  /* We treat these cases as a single byte character.  */
	  if (mbclen == 0 || remain_len == 0)
	    wc = L'\0';
	  else
	    wc = *(unsigned char *) (pstr->raw_mbs + rawbuf_idx);
	  mbclen = 1;
	  pstr->cur_state = prev_st;
	}
      else
	wc = wc2;
      /* Then proceed the next character.  */
      rawbuf_idx += mbclen;
    }
  *last_wc = wc;
  return rawbuf_idx;
}
#endif /* RE_ENABLE_I18N  */

/* Build the buffer PSTR->MBS, and apply the translation if we need.
   This function is used in case of REG_ICASE.  */

static void
internal_function
build_upper_buffer (re_string_t *pstr)
{
  Idx char_idx, end_idx;
  end_idx = (pstr->bufs_len > pstr->len) ? pstr->len : pstr->bufs_len;

  for (char_idx = pstr->valid_len; char_idx < end_idx; ++char_idx)
    {
      int ch = pstr->raw_mbs[pstr->raw_mbs_idx + char_idx];
      if (BE (pstr->trans != NULL, 0))
	ch = pstr->trans[ch];
      if (islower (ch))
	pstr->mbs[char_idx] = toupper (ch);
      else
	pstr->mbs[char_idx] = ch;
    }
  pstr->valid_len = char_idx;
  pstr->valid_raw_len = char_idx;
}

/* Apply TRANS to the buffer in PSTR.  */

static void
internal_function
re_string_translate_buffer (re_string_t *pstr)
{
  Idx buf_idx, end_idx;
  end_idx = (pstr->bufs_len > pstr->len) ? pstr->len : pstr->bufs_len;

  for (buf_idx = pstr->valid_len; buf_idx < end_idx; ++buf_idx)
    {
      int ch = pstr->raw_mbs[pstr->raw_mbs_idx + buf_idx];
      pstr->mbs[buf_idx] = pstr->trans[ch];
    }

  pstr->valid_len = buf_idx;
  pstr->valid_raw_len = buf_idx;
}

/* This function re-construct the buffers.
   Concretely, convert to wide character in case of pstr->mb_cur_max > 1,
   convert to upper case in case of REG_ICASE, apply translation.  */

static reg_errcode_t
internal_function
re_string_reconstruct (re_string_t *pstr, Idx idx, int eflags)
{
  Idx offset;

  if (BE (pstr->raw_mbs_idx <= idx, 0))
    offset = idx - pstr->raw_mbs_idx;
  else
    {
      /* Reset buffer.  */
#ifdef RE_ENABLE_I18N
      if (pstr->mb_cur_max > 1)
	memset (&pstr->cur_state, '\0', sizeof (mbstate_t));
#endif /* RE_ENABLE_I18N */
      pstr->len = pstr->raw_len;
      pstr->stop = pstr->raw_stop;
      pstr->valid_len = 0;
      pstr->raw_mbs_idx = 0;
      pstr->valid_raw_len = 0;
      pstr->offsets_needed = 0;
      pstr->tip_context = ((eflags & REG_NOTBOL) ? CONTEXT_BEGBUF
			   : CONTEXT_NEWLINE | CONTEXT_BEGBUF);
      if (!pstr->mbs_allocated)
	pstr->mbs = (unsigned char *) pstr->raw_mbs;
      offset = idx;
    }

  if (BE (offset != 0, 1))
    {
      /* Should the already checked characters be kept?  */
      if (BE (offset < pstr->valid_raw_len, 1))
	{
	  /* Yes, move them to the front of the buffer.  */
#ifdef RE_ENABLE_I18N
	  if (BE (pstr->offsets_needed, 0))
	    {
	      Idx low = 0, high = pstr->valid_len, mid;
	      do
		{
		  mid = (high + low) / 2;
		  if (pstr->offsets[mid] > offset)
		    high = mid;
		  else if (pstr->offsets[mid] < offset)
		    low = mid + 1;
		  else
		    break;
		}
	      while (low < high);
	      if (pstr->offsets[mid] < offset)
		++mid;
	      pstr->tip_context = re_string_context_at (pstr, mid - 1,
							eflags);
	      /* This can be quite complicated, so handle specially
		 only the common and easy case where the character with
		 different length representation of lower and upper
		 case is present at or after offset.  */
	      if (pstr->valid_len > offset
		  && mid == offset && pstr->offsets[mid] == offset)
		{
		  memmove (pstr->wcs, pstr->wcs + offset,
			   (pstr->valid_len - offset) * sizeof (wint_t));
		  memmove (pstr->mbs, pstr->mbs + offset, pstr->valid_len - offset);
		  pstr->valid_len -= offset;
		  pstr->valid_raw_len -= offset;
		  for (low = 0; low < pstr->valid_len; low++)
		    pstr->offsets[low] = pstr->offsets[low + offset] - offset;
		}
	      else
		{
		  /* Otherwise, just find out how long the partial multibyte
		     character at offset is and fill it with WEOF/255.  */
		  pstr->len = pstr->raw_len - idx + offset;
		  pstr->stop = pstr->raw_stop - idx + offset;
		  pstr->offsets_needed = 0;
		  while (mid > 0 && pstr->offsets[mid - 1] == offset)
		    --mid;
		  while (mid < pstr->valid_len)
		    if (pstr->wcs[mid] != WEOF)
		      break;
		    else
		      ++mid;
		  if (mid == pstr->valid_len)
		    pstr->valid_len = 0;
		  else
		    {
		      pstr->valid_len = pstr->offsets[mid] - offset;
		      if (pstr->valid_len)
			{
			  for (low = 0; low < pstr->valid_len; ++low)
			    pstr->wcs[low] = WEOF;
			  memset (pstr->mbs, 255, pstr->valid_len);
			}
		    }
		  pstr->valid_raw_len = pstr->valid_len;
		}
	    }
	  else
#endif
	    {
	      pstr->tip_context = re_string_context_at (pstr, offset - 1,
							eflags);
#ifdef RE_ENABLE_I18N
	      if (pstr->mb_cur_max > 1)
		memmove (pstr->wcs, pstr->wcs + offset,
			 (pstr->valid_len - offset) * sizeof (wint_t));
#endif /* RE_ENABLE_I18N */
	      if (BE (pstr->mbs_allocated, 0))
		memmove (pstr->mbs, pstr->mbs + offset,
			 pstr->valid_len - offset);
	      pstr->valid_len -= offset;
	      pstr->valid_raw_len -= offset;
#if DEBUG
	      assert (pstr->valid_len > 0);
#endif
	    }
	}
      else
	{
	  /* No, skip all characters until IDX.  */
	  Idx prev_valid_len = pstr->valid_len;

#ifdef RE_ENABLE_I18N
	  if (BE (pstr->offsets_needed, 0))
	    {
	      pstr->len = pstr->raw_len - idx + offset;
	      pstr->stop = pstr->raw_stop - idx + offset;
	      pstr->offsets_needed = 0;
	    }
#endif
	  pstr->valid_len = 0;
#ifdef RE_ENABLE_I18N
	  if (pstr->mb_cur_max > 1)
	    {
	      Idx wcs_idx;
	      wint_t wc = WEOF;

	      if (pstr->is_utf8)
		{
		  const unsigned char *raw, *p, *end;

		  /* Special case UTF-8.  Multi-byte chars start with any
		     byte other than 0x80 - 0xbf.  */
		  raw = pstr->raw_mbs + pstr->raw_mbs_idx;
		  end = raw + (offset - pstr->mb_cur_max);
		  if (end < pstr->raw_mbs)
		    end = pstr->raw_mbs;
		  p = raw + offset - 1;
#ifdef _LIBC
		  /* We know the wchar_t encoding is UCS4, so for the simple
		     case, ASCII characters, skip the conversion step.  */
		  if (isascii (*p) && BE (pstr->trans == NULL, 1))
		    {
		      memset (&pstr->cur_state, '\0', sizeof (mbstate_t));
		      /* pstr->valid_len = 0; */
		      wc = (wchar_t) *p;
		    }
		  else
#endif
		    for (; p >= end; --p)
		      if ((*p & 0xc0) != 0x80)
			{
			  mbstate_t cur_state;
			  wchar_t wc2;
			  Idx mlen = raw + pstr->len - p;
			  unsigned char buf[6];
			  size_t mbclen;

			  if (BE (pstr->trans != NULL, 0))
			    {
			      int i = mlen < 6 ? mlen : 6;
			      while (--i >= 0)
				buf[i] = pstr->trans[p[i]];
			    }
			  /* XXX Don't use mbrtowc, we know which conversion
			     to use (UTF-8 -> UCS4).  */
			  memset (&cur_state, 0, sizeof (cur_state));
			  mbclen = mbrtowc (&wc2, (const char *) p, mlen,
					    &cur_state);
			  if (raw + offset - p <= mbclen
			      && mbclen < (size_t) -2)
			    {
			      memset (&pstr->cur_state, '\0',
				      sizeof (mbstate_t));
			      pstr->valid_len = mbclen - (raw + offset - p);
			      wc = wc2;
			    }
			  break;
			}
		}

	      if (wc == WEOF)
		pstr->valid_len = re_string_skip_chars (pstr, idx, &wc) - idx;
	      if (wc == WEOF)
		pstr->tip_context
		  = re_string_context_at (pstr, prev_valid_len - 1, eflags);
	      else
		pstr->tip_context = ((BE (pstr->word_ops_used != 0, 0)
				      && IS_WIDE_WORD_CHAR (wc))
				     ? CONTEXT_WORD
				     : ((IS_WIDE_NEWLINE (wc)
					 && pstr->newline_anchor)
					? CONTEXT_NEWLINE : 0));
	      if (BE (pstr->valid_len, 0))
		{
		  for (wcs_idx = 0; wcs_idx < pstr->valid_len; ++wcs_idx)
		    pstr->wcs[wcs_idx] = WEOF;
		  if (pstr->mbs_allocated)
		    memset (pstr->mbs, 255, pstr->valid_len);
		}
	      pstr->valid_raw_len = pstr->valid_len;
	    }
	  else
#endif /* RE_ENABLE_I18N */
	    {
	      int c = pstr->raw_mbs[pstr->raw_mbs_idx + offset - 1];
	      pstr->valid_raw_len = 0;
	      if (pstr->trans)
		c = pstr->trans[c];
	      pstr->tip_context = (bitset_contain (pstr->word_char, c)
				   ? CONTEXT_WORD
				   : ((IS_NEWLINE (c) && pstr->newline_anchor)
				      ? CONTEXT_NEWLINE : 0));
	    }
	}
      if (!BE (pstr->mbs_allocated, 0))
	pstr->mbs += offset;
    }
  pstr->raw_mbs_idx = idx;
  pstr->len -= offset;
  pstr->stop -= offset;

  /* Then build the buffers.  */
#ifdef RE_ENABLE_I18N
  if (pstr->mb_cur_max > 1)
    {
      if (pstr->icase)
	{
	  reg_errcode_t ret = build_wcs_upper_buffer (pstr);
	  if (BE (ret != REG_NOERROR, 0))
	    return ret;
	}
      else
	build_wcs_buffer (pstr);
    }
  else
#endif /* RE_ENABLE_I18N */
    if (BE (pstr->mbs_allocated, 0))
      {
	if (pstr->icase)
	  build_upper_buffer (pstr);
	else if (pstr->trans != NULL)
	  re_string_translate_buffer (pstr);
      }
    else
      pstr->valid_len = pstr->len;

  pstr->cur_idx = 0;
  return REG_NOERROR;
}

static unsigned char
internal_function __attribute ((pure))
re_string_peek_byte_case (const re_string_t *pstr, Idx idx)
{
  int ch;
  Idx off;

  /* Handle the common (easiest) cases first.  */
  if (BE (!pstr->mbs_allocated, 1))
    return re_string_peek_byte (pstr, idx);

#ifdef RE_ENABLE_I18N
  if (pstr->mb_cur_max > 1
      && ! re_string_is_single_byte_char (pstr, pstr->cur_idx + idx))
    return re_string_peek_byte (pstr, idx);
#endif

  off = pstr->cur_idx + idx;
#ifdef RE_ENABLE_I18N
  if (pstr->offsets_needed)
    off = pstr->offsets[off];
#endif

  ch = pstr->raw_mbs[pstr->raw_mbs_idx + off];

#ifdef RE_ENABLE_I18N
  /* Ensure that e.g. for tr_TR.UTF-8 BACKSLASH DOTLESS SMALL LETTER I
     this function returns CAPITAL LETTER I instead of first byte of
     DOTLESS SMALL LETTER I.  The latter would confuse the parser,
     since peek_byte_case doesn't advance cur_idx in any way.  */
  if (pstr->offsets_needed && !isascii (ch))
    return re_string_peek_byte (pstr, idx);
#endif

  return ch;
}

static unsigned char
internal_function __attribute ((pure))