/**
* Initializes line breaking context for a given language.
*
* @param[in,out] lbpCtx pointer to the line breaking context
* @param[in] ch the first character to process
* @param[in] lang language of the input
* @post the line breaking context is initialized
*/
void lb_init_break_context(
struct LineBreakContext* lbpCtx,
utf32_t ch,
const char* lang)
{
lbpCtx->lang = lang;
lbpCtx->lbpLang = get_lb_prop_lang(lang);
lbpCtx->lbcLast = LBP_Undefined;
lbpCtx->lbcNew = LBP_Undefined;
lbpCtx->lbcCur = resolve_lb_class(
get_char_lb_class_lang(ch, lbpCtx->lbpLang),
lbpCtx->lang);
treat_first_char(lbpCtx);
}
/**
* Updates LineBreakingContext for the next code point and returns
* the detected break.
*
* @param[in,out] lbpCtx pointer to the line breaking context
* @param[in] ch Unicode code point
* @return break result, one of #LINEBREAK_MUSTBREAK,
* #LINEBREAK_ALLOWBREAK, and #LINEBREAK_NOBREAK
* @post the line breaking context is updated
*/
int lb_process_next_char(
struct LineBreakContext *lbpCtx,
utf32_t ch )
{
int brk;
lbpCtx->lbcLast = lbpCtx->lbcNew;
lbpCtx->lbcNew = get_char_lb_class_lang(ch, lbpCtx->lbpLang);
brk = get_lb_result_simple(lbpCtx);
switch (brk)
{
case LINEBREAK_MUSTBREAK:
lbpCtx->lbcCur = resolve_lb_class(lbpCtx->lbcNew, lbpCtx->lang);
treat_first_char(lbpCtx);
break;
case LINEBREAK_UNDEFINED:
lbpCtx->lbcNew = resolve_lb_class(lbpCtx->lbcNew, lbpCtx->lang);
brk = get_lb_result_lookup(lbpCtx);
break;
default:
break;
}
return brk;
}
/**
* Sets the line breaking information for a generic input string.
*
* @param[in] s input string
* @param[in] len length of the input
* @param[in] lang language of the input
* @param[out] brks pointer to the output breaking data,
* containing #LINEBREAK_MUSTBREAK,
* #LINEBREAK_ALLOWBREAK, #LINEBREAK_NOBREAK,
* or #LINEBREAK_INSIDEACHAR
* @param[in] get_next_char function to get the next UTF-32 character
*/
void set_linebreaks(
const void *s,
size_t len,
const char *lang,
char *brks,
get_next_char_t get_next_char)
{
utf32_t ch;
enum LineBreakClass lbcCur;
enum LineBreakClass lbcNew;
enum LineBreakClass lbcLast;
struct LineBreakProperties *lbpLang;
size_t posCur = 0;
size_t posLast = 0;
--posLast; /* To be ++'d later */
ch = get_next_char(s, len, &posCur);
if (ch == EOS)
return;
lbpLang = get_lb_prop_lang(lang);
lbcCur = resolve_lb_class(get_char_lb_class_lang(ch, lbpLang), lang);
lbcNew = LBP_Undefined;
nextline:
/* Special treatment for the first character */
switch (lbcCur)
{
case LBP_LF:
case LBP_NL:
lbcCur = LBP_BK;
break;
case LBP_CB:
lbcCur = LBP_BA;
break;
case LBP_SP:
lbcCur = LBP_WJ;
break;
default:
break;
}
/* Process a line till an explicit break or end of string */
for (;;)
{
for (++posLast; posLast < posCur - 1; ++posLast)
{
brks[posLast] = LINEBREAK_INSIDEACHAR;
}
assert(posLast == posCur - 1);
lbcLast = lbcNew;
ch = get_next_char(s, len, &posCur);
if (ch == EOS)
break;
lbcNew = get_char_lb_class_lang(ch, lbpLang);
if (lbcCur == LBP_BK || (lbcCur == LBP_CR && lbcNew != LBP_LF))
{
brks[posLast] = LINEBREAK_MUSTBREAK;
lbcCur = resolve_lb_class(lbcNew, lang);
goto nextline;
}
switch (lbcNew)
{
case LBP_SP:
brks[posLast] = LINEBREAK_NOBREAK;
continue;
case LBP_BK:
case LBP_LF:
case LBP_NL:
brks[posLast] = LINEBREAK_NOBREAK;
lbcCur = LBP_BK;
continue;
case LBP_CR:
brks[posLast] = LINEBREAK_NOBREAK;
lbcCur = LBP_CR;
continue;
case LBP_CB:
brks[posLast] = LINEBREAK_ALLOWBREAK;
lbcCur = LBP_BA;
continue;
default:
break;
}
lbcNew = resolve_lb_class(lbcNew, lang);
assert(lbcCur <= LBP_JT);
assert(lbcNew <= LBP_JT);
switch (baTable[lbcCur - 1][lbcNew - 1])
{
case DIR_BRK:
brks[posLast] = LINEBREAK_ALLOWBREAK;
break;
case CMI_BRK:
case IND_BRK:
if (lbcLast == LBP_SP)
{
brks[posLast] = LINEBREAK_ALLOWBREAK;
}
else
{
brks[posLast] = LINEBREAK_NOBREAK;
}
break;
case CMP_BRK:
brks[posLast] = LINEBREAK_NOBREAK;
if (lbcLast != LBP_SP)
continue;
break;
case PRH_BRK:
brks[posLast] = LINEBREAK_NOBREAK;
break;
}
lbcCur = lbcNew;
}
assert(posLast == posCur - 1 && posCur <= len);
/* Break after the last character */
brks[posLast] = LINEBREAK_MUSTBREAK;
/* When the input contains incomplete sequences */
while (posCur < len)
{
brks[posCur++] = LINEBREAK_INSIDEACHAR;
}
}
