/* Truncate multi-byte string to @width and returns number of
* bytes of the new string @str, and in @width returns number
* of cells.
*/
size_t
mbs_truncate(char *str, size_t *width)
{
size_t bytes = strlen(str);
#ifdef HAVE_WIDECHAR
size_t sz = mbstowcs(NULL, str, 0);
wchar_t *wcs = NULL;
if (sz == (size_t) -1)
goto done;
wcs = malloc((sz + 1) * sizeof(wchar_t));
if (!wcs)
goto done;
if (!mbstowcs(wcs, str, sz))
goto done;
*width = wc_truncate(wcs, *width);
bytes = wcstombs(str, wcs, bytes);
done:
free(wcs);
#else
if (*width < bytes)
bytes = *width;
#endif
if (bytes >= 0)
str[bytes] = '\0';
return bytes;
}
size_t
mbsalign (const char *src, char *dest, size_t dest_size,
size_t *width, mbs_align_t align, int flags)
{
size_t ret = -1;
size_t src_size = strlen (src) + 1;
char *newstr = NULL;
wchar_t *str_wc = NULL;
const char *str_to_print = src;
size_t n_cols = src_size - 1;
size_t n_used_bytes = n_cols; /* Not including NUL */
size_t n_spaces = 0;
bool conversion = false;
bool wc_enabled = false;
#ifdef HAVE_WIDECHAR
/* In multi-byte locales convert to wide characters
to allow easy truncation. Also determine number
of screen columns used. */
if (MB_CUR_MAX > 1)
{
size_t src_chars = mbstowcs (NULL, src, 0);
if (src_chars == (size_t) -1)
{
if (flags & MBA_UNIBYTE_FALLBACK)
goto mbsalign_unibyte;
else
goto mbsalign_cleanup;
}
src_chars += 1; /* make space for NUL */
str_wc = malloc (src_chars * sizeof (wchar_t));
if (str_wc == NULL)
{
if (flags & MBA_UNIBYTE_FALLBACK)
goto mbsalign_unibyte;
else
goto mbsalign_cleanup;
}
if (mbstowcs (str_wc, src, src_chars) != 0)
{
str_wc[src_chars - 1] = L'\0';
wc_enabled = true;
conversion = wc_ensure_printable (str_wc);
n_cols = rpl_wcswidth (str_wc, src_chars);
}
}
/* If we transformed or need to truncate the source string
then create a modified copy of it. */
if (wc_enabled && (conversion || (n_cols > *width)))
{
if (conversion)
{
/* May have increased the size by converting
\t to \uFFFD for example. */
src_size = wcstombs(NULL, str_wc, 0) + 1;
}
newstr = malloc (src_size);
if (newstr == NULL)
{
if (flags & MBA_UNIBYTE_FALLBACK)
goto mbsalign_unibyte;
else
goto mbsalign_cleanup;
}
str_to_print = newstr;
n_cols = wc_truncate (str_wc, *width);
n_used_bytes = wcstombs (newstr, str_wc, src_size);
}
#endif
mbsalign_unibyte:
if (n_cols > *width) /* Unibyte truncation required. */
{
n_cols = *width;
n_used_bytes = n_cols;
}
if (*width > n_cols) /* Padding required. */
n_spaces = *width - n_cols;
/* indicate to caller how many cells needed (not including padding). */
*width = n_cols;
/* indicate to caller how many bytes needed (not including NUL). */
ret = n_used_bytes + (n_spaces * 1);
/* Write as much NUL terminated output to DEST as possible. */
if (dest_size != 0)
{
char *dest_end = dest + dest_size - 1;
size_t start_spaces = n_spaces / 2 + n_spaces % 2;
size_t end_spaces = n_spaces / 2;
switch (align)
{
case MBS_ALIGN_CENTER:
start_spaces = n_spaces / 2 + n_spaces % 2;
end_spaces = n_spaces / 2;
break;
case MBS_ALIGN_LEFT:
start_spaces = 0;
end_spaces = n_spaces;
break;
case MBS_ALIGN_RIGHT:
start_spaces = n_spaces;
end_spaces = 0;
break;
}
dest = mbs_align_pad (dest, dest_end, start_spaces);
size_t space_left = dest_end - dest;
dest = mempcpy (dest, str_to_print, min (n_used_bytes, space_left));
mbs_align_pad (dest, dest_end, end_spaces);
}
mbsalign_cleanup:
free (str_wc);
free (newstr);
return ret;
}
size_t
mbsalign (const char *src, char *dest, size_t dest_size,
size_t *width, mbs_align_t align, int flags)
{
size_t ret = -1;
size_t src_size = strlen (src) + 1;
char *newstr = NULL;
wchar_t *str_wc = NULL;
const char *str_to_print = src;
size_t n_cols = src_size - 1;
size_t n_used_bytes = n_cols; /* Not including NUL */
size_t n_spaces = 0;
bool conversion = false;
bool wc_enabled = false;
/* In multi-byte locales convert to wide characters
to allow easy truncation. Also determine number
of screen columns used. */
if (MB_CUR_MAX > 1)
{
size_t src_chars = mbstowcs (NULL, src, 0);
if (src_chars == (size_t) -1)
goto mbsalign_cleanup;
src_chars += 1; /* make space for NUL */
str_wc = malloc (src_chars * sizeof (wchar_t));
if (str_wc == NULL)
goto mbsalign_cleanup;
if (mbstowcs (str_wc, src, src_chars) > 0)
{
str_wc[src_chars - 1] = L'\0';
wc_enabled = true;
conversion = wc_ensure_printable (str_wc);
n_cols = rpl_wcswidth (str_wc, src_chars);
}
}
/* If we transformed or need to truncate the source string
then create a modified copy of it. */
if (conversion || (n_cols > *width))
{
newstr = malloc (src_size);
if (newstr == NULL)
goto mbsalign_cleanup;
str_to_print = newstr;
if (wc_enabled)
{
n_cols = wc_truncate (str_wc, *width);
n_used_bytes = wcstombs (newstr, str_wc, src_size);
}
else
{
n_cols = *width;
n_used_bytes = n_cols;
memcpy (newstr, src, n_cols);
newstr[n_cols] = '\0';
}
}
if (*width > n_cols)
n_spaces = *width - n_cols;
/* indicate to caller how many cells needed (not including padding). */
*width = n_cols;
/* indicate to caller how many bytes needed (not including NUL). */
ret = n_used_bytes + (n_spaces * 1);
/* Write as much NUL terminated output to DEST as possible. */
if (dest_size != 0)
{
char *dest_end = dest + dest_size - 1;
size_t start_spaces = n_spaces / 2 + n_spaces % 2;
size_t end_spaces = n_spaces / 2;
switch (align)
{
case MBS_ALIGN_CENTER:
start_spaces = n_spaces / 2 + n_spaces % 2;
end_spaces = n_spaces / 2;
break;
case MBS_ALIGN_LEFT:
start_spaces = 0;
end_spaces = n_spaces;
break;
case MBS_ALIGN_RIGHT:
start_spaces = n_spaces;
end_spaces = 0;
break;
}
dest = mbs_align_pad (dest, dest_end, start_spaces);
dest = mempcpy(dest, str_to_print, MIN (n_used_bytes, dest_end - dest));
mbs_align_pad (dest, dest_end, end_spaces);
}
mbsalign_cleanup:
free (str_wc);
free (newstr);
return ret;
}
