void luaV_concat (lua_State *L, int total, int last) {
do {
StkId top = L->base + last + 1;
int n = 2; /* number of elements handled in this pass (at least 2) */
if (!(ttisstring(top-2) || ttisnumber(top-2)) || !tostring(L, top-1)) {
if (!call_binTM(L, top-2, top-1, top-2, TM_CONCAT))
luaG_concaterror(L, top-2, top-1);
} else if (tsvalue(top-1)->len == 0) /* second op is empty? */
(void)tostring(L, top - 2); /* result is first op (as string) */
else {
/* at least two string values; get as many as possible */
size_t tl = tsvalue(top-1)->len;
char *buffer;
int i;
/* collect total length */
for (n = 1; n < total && tostring(L, top-n-1); n++) {
size_t l = tsvalue(top-n-1)->len;
if (l >= MAX_SIZET - tl) luaG_runerror(L, "string length overflow");
tl += l;
}
G(L)->buff.n = tl;
buffer = luaZ_openspace(L, &G(L)->buff, tl);
tl = 0;
for (i=n; i>0; i--) { /* concat all strings */
size_t l = tsvalue(top-i)->len;
memcpy(buffer+tl, svalue(top-i), l);
tl += l;
}
setsvalue2s(L, top-n, luaS_newlstr(L, buffer, tl));
luaZ_resetbuffer(&G(L)->buff);
}
total -= n-1; /* got `n' strings to create 1 new */
last -= n-1;
} while (total > 1); /* repeat until only 1 result left */
}
void luaV_concat (lua_State *L, int total, int last) {
lu_mem max_sizet = MAX_SIZET;
if (G(L)->memlimit < max_sizet) max_sizet = G(L)->memlimit;
do {
/* Any call which does a memory allocation may trim the stack,
invalidating top unless the stack is fixed duri ng the allocation */
StkId top = L->base + last + 1;
fixedstack(L);
int n = 2; /* number of elements handled in this pass (at least 2) */
if (!(ttisstring(top-2) || ttisnumber(top-2)) || !tostring(L, top-1)) {
unfixedstack(L);
if (!call_binTM(L, top-2, top-1, top-2, TM_CONCAT)) {
/* restore 'top' pointer, since stack might have been reallocted */
top = L->base + last + 1;
luaG_concaterror(L, top-2, top-1);
}
} else if (tsvalue(top-1)->len == 0) { /* second op is empty? */
(void)tostring(L, top - 2); /* result is first op (as string) */
} else {
/* at least two string values; get as many as possible */
size_t tl = tsvalue(top-1)->len;
char *buffer;
int i;
/* collect total length */
for (n = 1; n < total && tostring(L, top-n-1); n++) {
size_t l = tsvalue(top-n-1)->len;
if (l >= max_sizet - tl) luaG_runerror(L, "string length overflow");
tl += l;
}
G(L)->buff.n = tl;
buffer = luaZ_openspace(L, &G(L)->buff, tl);
tl = 0;
for (i=n; i>0; i--) { /* concat all strings */
size_t l = tsvalue(top-i)->len;
c_memcpy(buffer+tl, svalue(top-i), l);
tl += l;
}
setsvalue2s(L, top-n, luaS_newlstr(L, buffer, tl));
luaZ_resetbuffer(&G(L)->buff);
}
total -= n-1; /* got `n' strings to create 1 new */
last -= n-1;
unfixedstack(L);
} while (total > 1); /* repeat until only 1 result left */
}
static void read_long_string (LexState *ls, SemInfo *seminfo, int sep) {
int line = ls->linenumber; /* initial line (for error message) */
save_and_next(ls); /* skip 2nd '[' */
if (currIsNewline(ls)) /* string starts with a newline? */
inclinenumber(ls); /* skip it */
for (;;) {
switch (ls->current) {
case EOZ: { /* error */
const char *what = (seminfo ? "string" : "comment");
const char *msg = luaO_pushfstring(ls->L,
"unfinished long %s (starting at line %d)", what, line);
lexerror(ls, msg, TK_EOS);
break; /* to avoid warnings */
}
case ']': {
if (skip_sep(ls) == sep) {
save_and_next(ls); /* skip 2nd ']' */
goto endloop;
}
break;
}
case '\n':
case '\r': {
save(ls, '\n');
inclinenumber(ls);
if (!seminfo) luaZ_resetbuffer(ls->buff); /* avoid wasting space */
break;
}
default: {
if (seminfo) save_and_next(ls);
else next(ls);
}
}
}
endloop:
if (seminfo)
seminfo->ts = luaX_newstring(ls, luaZ_buffer(ls->buff) + (2 + sep),
luaZ_bufflen(ls->buff) - 2*(2 + sep));
}
static int llex (LexState *ls, SemInfo *seminfo) {
luaZ_resetbuffer(ls->buff);
for (;;) {
switch (ls->current) {
case '\n': case '\r': { /* line breaks */
inclinenumber(ls);
break;
}
case ' ': case '\f': case '\t': case '\v': { /* spaces */
next(ls);
break;
}
case '-': { /* '-' or '--' (comment) */
next(ls);
if (ls->current != '-') return '-';
/* else is a comment */
next(ls);
if (ls->current == '[') { /* long comment? */
int sep = skip_sep(ls);
luaZ_resetbuffer(ls->buff); /* 'skip_sep' may dirty the buffer */
if (sep >= 0) {
read_long_string(ls, NULL, sep); /* skip long comment */
luaZ_resetbuffer(ls->buff); /* previous call may dirty the buff. */
break;
}
}
/* else short comment */
while (!currIsNewline(ls) && ls->current != EOZ)
next(ls); /* skip until end of line (or end of file) */
break;
}
case '[': { /* long string or simply '[' */
int sep = skip_sep(ls);
if (sep >= 0) {
read_long_string(ls, seminfo, sep);
return TK_STRING;
}
else if (sep != -1) /* '[=...' missing second bracket */
lexerror(ls, "invalid long string delimiter", TK_STRING);
return '[';
}
case '=': {
next(ls);
if (check_next1(ls, '=')) return TK_EQ;
else return '=';
}
case '<': {
next(ls);
if (check_next1(ls, '=')) return TK_LE;
else if (check_next1(ls, '<')) return TK_SHL;
else return '<';
}
case '>': {
next(ls);
if (check_next1(ls, '=')) return TK_GE;
else if (check_next1(ls, '>')) return TK_SHR;
else return '>';
}
case '/': {
next(ls);
if (check_next1(ls, '/')) return TK_IDIV;
else return '/';
}
case '~': {
next(ls);
if (check_next1(ls, '=')) return TK_NE;
else return '~';
}
case ':': {
next(ls);
if (check_next1(ls, ':')) return TK_DBCOLON;
else return ':';
}
case '"': case '\'': { /* short literal strings */
read_string(ls, ls->current, seminfo);
return TK_STRING;
}
case '`': { /* relative paths */
read_string(ls, ls->current, seminfo);
return TK_PATH;
}
case '.': { /* '.', '..', '...', or number */
save_and_next(ls);
if (check_next1(ls, '.')) {
if (check_next1(ls, '.'))
return TK_DOTS; /* '...' */
else return TK_CONCAT; /* '..' */
}
else if (!lisdigit(ls->current)) return '.';
else return read_numeral(ls, seminfo);
}
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9': {
return read_numeral(ls, seminfo);
}
case EOZ: {
return TK_EOS;
}
default: {
if (lislalpha(ls->current)) { /* identifier or reserved word? */
TString *ts;
do {
save_and_next(ls);
} while (lislalnum(ls->current));
ts = luaX_newstring(ls, luaZ_buffer(ls->buff),
luaZ_bufflen(ls->buff));
seminfo->ts = ts;
if (isreserved(ts)) /* reserved word? */
return ts->extra - 1 + FIRST_RESERVED;
else {
return TK_NAME;
}
}
else { /* single-char tokens (+ - / ...) */
int c = ls->current;
next(ls);
return c;
}
}
}
}
}
