ref: 77ab465f1c394bb77f00966cd950650f3f53cb24
dir: /jslex.c/
#include "jsi.h"
#include "jslex.h"
#include "utf.h"
JS_NORETURN static void jsY_error(js_State *J, const char *fmt, ...) JS_PRINTFLIKE(2,3);
static void jsY_error(js_State *J, const char *fmt, ...)
{
va_list ap;
char buf[512];
char msgbuf[256];
va_start(ap, fmt);
vsnprintf(msgbuf, 256, fmt, ap);
va_end(ap);
snprintf(buf, 256, "%s:%d: ", J->filename, J->lexline);
strcat(buf, msgbuf);
js_newsyntaxerror(J, buf);
js_throw(J);
}
static const char *tokenstring[] = {
"(end-of-file)",
"'\\x01'", "'\\x02'", "'\\x03'", "'\\x04'", "'\\x05'", "'\\x06'", "'\\x07'",
"'\\x08'", "'\\x09'", "'\\x0A'", "'\\x0B'", "'\\x0C'", "'\\x0D'", "'\\x0E'", "'\\x0F'",
"'\\x10'", "'\\x11'", "'\\x12'", "'\\x13'", "'\\x14'", "'\\x15'", "'\\x16'", "'\\x17'",
"'\\x18'", "'\\x19'", "'\\x1A'", "'\\x1B'", "'\\x1C'", "'\\x1D'", "'\\x1E'", "'\\x1F'",
"' '", "'!'", "'\"'", "'#'", "'$'", "'%'", "'&'", "'\\''",
"'('", "')'", "'*'", "'+'", "','", "'-'", "'.'", "'/'",
"'0'", "'1'", "'2'", "'3'", "'4'", "'5'", "'6'", "'7'",
"'8'", "'9'", "':'", "';'", "'<'", "'='", "'>'", "'?'",
"'@'", "'A'", "'B'", "'C'", "'D'", "'E'", "'F'", "'G'",
"'H'", "'I'", "'J'", "'K'", "'L'", "'M'", "'N'", "'O'",
"'P'", "'Q'", "'R'", "'S'", "'T'", "'U'", "'V'", "'W'",
"'X'", "'Y'", "'Z'", "'['", "'\'", "']'", "'^'", "'_'",
"'`'", "'a'", "'b'", "'c'", "'d'", "'e'", "'f'", "'g'",
"'h'", "'i'", "'j'", "'k'", "'l'", "'m'", "'n'", "'o'",
"'p'", "'q'", "'r'", "'s'", "'t'", "'u'", "'v'", "'w'",
"'x'", "'y'", "'z'", "'{'", "'|'", "'}'", "'~'", "'\\x7F'",
0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0,
0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0,
0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0,
0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0,
0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0,
0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0,
0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0,
0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0,
"(identifier)", "(number)", "(string)", "(regexp)",
"'<='", "'>='", "'=='", "'!='", "'==='", "'!=='",
"'<<'", "'>>'", "'>>>'", "'&&'", "'||'",
"'+='", "'-='", "'*='", "'/='", "'%='",
"'<<='", "'>>='", "'>>>='", "'&='", "'|='", "'^='",
"'++'", "'--'",
"'break'", "'case'", "'catch'", "'continue'", "'debugger'",
"'default'", "'delete'", "'do'", "'else'", "'false'", "'finally'", "'for'",
"'function'", "'if'", "'in'", "'instanceof'", "'new'", "'null'", "'return'",
"'switch'", "'this'", "'throw'", "'true'", "'try'", "'typeof'", "'var'",
"'void'", "'while'", "'with'",
};
const char *jsY_tokenstring(int token)
{
if (token >= 0 && token < (int)nelem(tokenstring))
if (tokenstring[token])
return tokenstring[token];
return "<unknown>";
}
static const char *keywords[] = {
"break", "case", "catch", "continue", "debugger", "default", "delete",
"do", "else", "false", "finally", "for", "function", "if", "in",
"instanceof", "new", "null", "return", "switch", "this", "throw",
"true", "try", "typeof", "var", "void", "while", "with",
};
int jsY_findword(const char *s, const char **list, int num)
{
int l = 0;
int r = num - 1;
while (l <= r) {
int m = (l + r) >> 1;
int c = strcmp(s, list[m]);
if (c < 0)
r = m - 1;
else if (c > 0)
l = m + 1;
else
return m;
}
return -1;
}
static int jsY_findkeyword(js_State *J, const char *s)
{
int i = jsY_findword(s, keywords, nelem(keywords));
if (i >= 0) {
J->text = keywords[i];
return TK_BREAK + i; /* first keyword + i */
}
J->text = js_intern(J, s);
return TK_IDENTIFIER;
}
int jsY_iswhite(int c)
{
return c == 0x9 || c == 0xB || c == 0xC || c == 0x20 || c == 0xA0 || c == 0xFEFF;
}
int jsY_isnewline(int c)
{
return c == 0xA || c == 0xD || c == 0x2028 || c == 0x2029;
}
#define isalpha(c) ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z'))
#define isdigit(c) (c >= '0' && c <= '9')
#define ishex(c) ((c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F'))
static int jsY_isidentifierstart(int c)
{
return isalpha(c) || c == '$' || c == '_' || isalpharune(c);
}
static int jsY_isidentifierpart(int c)
{
return isdigit(c) || isalpha(c) || c == '$' || c == '_' || isalpharune(c);
}
static int jsY_isdec(int c)
{
return isdigit(c);
}
int jsY_ishex(int c)
{
return isdigit(c) || ishex(c);
}
int jsY_tohex(int c)
{
if (c >= '0' && c <= '9') return c - '0';
if (c >= 'a' && c <= 'f') return c - 'a' + 0xA;
if (c >= 'A' && c <= 'F') return c - 'A' + 0xA;
return 0;
}
static void jsY_next(js_State *J)
{
Rune c;
J->source += chartorune(&c, J->source);
/* consume CR LF as one unit */
if (c == '\r' && *J->source == '\n')
++J->source;
if (jsY_isnewline(c)) {
J->line++;
c = '\n';
}
J->lexchar = c;
}
#define jsY_accept(J, x) (J->lexchar == x ? (jsY_next(J), 1) : 0)
#define jsY_expect(J, x) if (!jsY_accept(J, x)) jsY_error(J, "expected '%c'", x)
static void jsY_unescape(js_State *J)
{
if (jsY_accept(J, '\\')) {
if (jsY_accept(J, 'u')) {
int x = 0;
if (!jsY_ishex(J->lexchar)) { goto error; } x |= jsY_tohex(J->lexchar) << 12; jsY_next(J);
if (!jsY_ishex(J->lexchar)) { goto error; } x |= jsY_tohex(J->lexchar) << 8; jsY_next(J);
if (!jsY_ishex(J->lexchar)) { goto error; } x |= jsY_tohex(J->lexchar) << 4; jsY_next(J);
if (!jsY_ishex(J->lexchar)) { goto error; } x |= jsY_tohex(J->lexchar);
J->lexchar = x;
return;
}
error:
jsY_error(J, "unexpected escape sequence");
}
}
static void textinit(js_State *J)
{
if (!J->lexbuf.text) {
J->lexbuf.cap = 4096;
J->lexbuf.text = js_malloc(J, J->lexbuf.cap);
}
J->lexbuf.len = 0;
}
static void textpush(js_State *J, Rune c)
{
int n = runelen(c);
if (J->lexbuf.len + n > J->lexbuf.cap) {
J->lexbuf.cap = J->lexbuf.cap * 2;
J->lexbuf.text = js_realloc(J, J->lexbuf.text, J->lexbuf.cap);
}
J->lexbuf.len += runetochar(J->lexbuf.text + J->lexbuf.len, &c);
}
static char *textend(js_State *J)
{
textpush(J, 0);
return J->lexbuf.text;
}
static void lexlinecomment(js_State *J)
{
while (J->lexchar && J->lexchar != '\n')
jsY_next(J);
}
static int lexcomment(js_State *J)
{
/* already consumed initial '/' '*' sequence */
while (J->lexchar != 0) {
if (jsY_accept(J, '*')) {
while (J->lexchar == '*')
jsY_next(J);
if (jsY_accept(J, '/'))
return 0;
}
else
jsY_next(J);
}
return -1;
}
static double lexhex(js_State *J)
{
double n = 0;
if (!jsY_ishex(J->lexchar))
jsY_error(J, "malformed hexadecimal number");
while (jsY_ishex(J->lexchar)) {
n = n * 16 + jsY_tohex(J->lexchar);
jsY_next(J);
}
return n;
}
#if 0
static double lexinteger(js_State *J)
{
double n = 0;
if (!jsY_isdec(J->lexchar))
jsY_error(J, "malformed number");
while (jsY_isdec(J->lexchar)) {
n = n * 10 + (J->lexchar - '0');
jsY_next(J);
}
return n;
}
static double lexfraction(js_State *J)
{
double n = 0;
double d = 1;
while (jsY_isdec(J->lexchar)) {
n = n * 10 + (J->lexchar - '0');
d = d * 10;
jsY_next(J);
}
return n / d;
}
static double lexexponent(js_State *J)
{
double sign;
if (jsY_accept(J, 'e') || jsY_accept(J, 'E')) {
if (jsY_accept(J, '-')) sign = -1;
else if (jsY_accept(J, '+')) sign = 1;
else sign = 1;
return sign * lexinteger(J);
}
return 0;
}
static int lexnumber(js_State *J)
{
double n;
double e;
if (jsY_accept(J, '0')) {
if (jsY_accept(J, 'x') || jsY_accept(J, 'X')) {
J->number = lexhex(J);
return TK_NUMBER;
}
if (jsY_isdec(J->lexchar))
jsY_error(J, "number with leading zero");
n = 0;
if (jsY_accept(J, '.'))
n += lexfraction(J);
} else if (jsY_accept(J, '.')) {
if (!jsY_isdec(J->lexchar))
return '.';
n = lexfraction(J);
} else {
n = lexinteger(J);
if (jsY_accept(J, '.'))
n += lexfraction(J);
}
e = lexexponent(J);
if (e < 0)
n /= pow(10, -e);
else if (e > 0)
n *= pow(10, e);
if (jsY_isidentifierstart(J->lexchar))
jsY_error(J, "number with letter suffix");
J->number = n;
return TK_NUMBER;
}
#else
static int lexnumber(js_State *J)
{
const char *s = J->source - 1;
if (jsY_accept(J, '0')) {
if (jsY_accept(J, 'x') || jsY_accept(J, 'X')) {
J->number = lexhex(J);
return TK_NUMBER;
}
if (jsY_isdec(J->lexchar))
jsY_error(J, "number with leading zero");
if (jsY_accept(J, '.')) {
while (jsY_isdec(J->lexchar))
jsY_next(J);
}
} else if (jsY_accept(J, '.')) {
if (!jsY_isdec(J->lexchar))
return '.';
while (jsY_isdec(J->lexchar))
jsY_next(J);
} else {
while (jsY_isdec(J->lexchar))
jsY_next(J);
if (jsY_accept(J, '.')) {
while (jsY_isdec(J->lexchar))
jsY_next(J);
}
}
if (jsY_accept(J, 'e') || jsY_accept(J, 'E')) {
if (J->lexchar == '-' || J->lexchar == '+')
jsY_next(J);
while (jsY_isdec(J->lexchar))
jsY_next(J);
}
if (jsY_isidentifierstart(J->lexchar))
jsY_error(J, "number with letter suffix");
J->number = js_strtod(s, NULL);
return TK_NUMBER;
}
#endif
static int lexescape(js_State *J)
{
int x = 0;
/* already consumed '\' */
if (jsY_accept(J, '\n'))
return 0;
switch (J->lexchar) {
case 0: jsY_error(J, "unterminated escape sequence");
case 'u':
jsY_next(J);
if (!jsY_ishex(J->lexchar)) return 1; else { x |= jsY_tohex(J->lexchar) << 12; jsY_next(J); }
if (!jsY_ishex(J->lexchar)) return 1; else { x |= jsY_tohex(J->lexchar) << 8; jsY_next(J); }
if (!jsY_ishex(J->lexchar)) return 1; else { x |= jsY_tohex(J->lexchar) << 4; jsY_next(J); }
if (!jsY_ishex(J->lexchar)) return 1; else { x |= jsY_tohex(J->lexchar); jsY_next(J); }
textpush(J, x);
break;
case 'x':
jsY_next(J);
if (!jsY_ishex(J->lexchar)) return 1; else { x |= jsY_tohex(J->lexchar) << 4; jsY_next(J); }
if (!jsY_ishex(J->lexchar)) return 1; else { x |= jsY_tohex(J->lexchar); jsY_next(J); }
textpush(J, x);
break;
case '0': textpush(J, 0); jsY_next(J); break;
case '\\': textpush(J, '\\'); jsY_next(J); break;
case '\'': textpush(J, '\''); jsY_next(J); break;
case '"': textpush(J, '"'); jsY_next(J); break;
case 'b': textpush(J, '\b'); jsY_next(J); break;
case 'f': textpush(J, '\f'); jsY_next(J); break;
case 'n': textpush(J, '\n'); jsY_next(J); break;
case 'r': textpush(J, '\r'); jsY_next(J); break;
case 't': textpush(J, '\t'); jsY_next(J); break;
case 'v': textpush(J, '\v'); jsY_next(J); break;
default: textpush(J, J->lexchar); jsY_next(J); break;
}
return 0;
}
static int lexstring(js_State *J)
{
const char *s;
int q = J->lexchar;
jsY_next(J);
textinit(J);
while (J->lexchar != q) {
if (J->lexchar == 0 || J->lexchar == '\n')
jsY_error(J, "string not terminated");
if (jsY_accept(J, '\\')) {
if (lexescape(J))
jsY_error(J, "malformed escape sequence");
} else {
textpush(J, J->lexchar);
jsY_next(J);
}
}
jsY_expect(J, q);
s = textend(J);
J->text = js_intern(J, s);
return TK_STRING;
}
/* the ugliest language wart ever... */
static int isregexpcontext(int last)
{
switch (last) {
case ']':
case ')':
case '}':
case TK_IDENTIFIER:
case TK_NUMBER:
case TK_STRING:
case TK_FALSE:
case TK_NULL:
case TK_THIS:
case TK_TRUE:
return 0;
default:
return 1;
}
}
static int lexregexp(js_State *J)
{
const char *s;
int g, m, i;
int inclass = 0;
/* already consumed initial '/' */
textinit(J);
/* regexp body */
while (J->lexchar != '/' || inclass) {
if (J->lexchar == 0 || J->lexchar == '\n') {
jsY_error(J, "regular expression not terminated");
} else if (jsY_accept(J, '\\')) {
if (jsY_accept(J, '/')) {
textpush(J, '/');
} else {
textpush(J, '\\');
if (J->lexchar == 0 || J->lexchar == '\n')
jsY_error(J, "regular expression not terminated");
textpush(J, J->lexchar);
jsY_next(J);
}
} else {
if (J->lexchar == '[' && !inclass)
inclass = 1;
if (J->lexchar == ']' && inclass)
inclass = 0;
textpush(J, J->lexchar);
jsY_next(J);
}
}
jsY_expect(J, '/');
s = textend(J);
/* regexp flags */
g = i = m = 0;
while (jsY_isidentifierpart(J->lexchar)) {
if (jsY_accept(J, 'g')) ++g;
else if (jsY_accept(J, 'i')) ++i;
else if (jsY_accept(J, 'm')) ++m;
else jsY_error(J, "illegal flag in regular expression: %c", J->lexchar);
}
if (g > 1 || i > 1 || m > 1)
jsY_error(J, "duplicated flag in regular expression");
J->text = js_intern(J, s);
J->number = 0;
if (g) J->number += JS_REGEXP_G;
if (i) J->number += JS_REGEXP_I;
if (m) J->number += JS_REGEXP_M;
return TK_REGEXP;
}
/* simple "return [no Line Terminator here] ..." contexts */
static int isnlthcontext(int last)
{
switch (last) {
case TK_BREAK:
case TK_CONTINUE:
case TK_RETURN:
case TK_THROW:
return 1;
default:
return 0;
}
}
static int jsY_lexx(js_State *J)
{
J->newline = 0;
while (1) {
J->lexline = J->line; /* save location of beginning of token */
while (jsY_iswhite(J->lexchar))
jsY_next(J);
if (jsY_accept(J, '\n')) {
J->newline = 1;
if (isnlthcontext(J->lasttoken))
return ';';
continue;
}
if (jsY_accept(J, '/')) {
if (jsY_accept(J, '/')) {
lexlinecomment(J);
continue;
} else if (jsY_accept(J, '*')) {
if (lexcomment(J))
jsY_error(J, "multi-line comment not terminated");
continue;
} else if (isregexpcontext(J->lasttoken)) {
return lexregexp(J);
} else if (jsY_accept(J, '=')) {
return TK_DIV_ASS;
} else {
return '/';
}
}
if (J->lexchar >= '0' && J->lexchar <= '9') {
return lexnumber(J);
}
switch (J->lexchar) {
case '(': jsY_next(J); return '(';
case ')': jsY_next(J); return ')';
case ',': jsY_next(J); return ',';
case ':': jsY_next(J); return ':';
case ';': jsY_next(J); return ';';
case '?': jsY_next(J); return '?';
case '[': jsY_next(J); return '[';
case ']': jsY_next(J); return ']';
case '{': jsY_next(J); return '{';
case '}': jsY_next(J); return '}';
case '~': jsY_next(J); return '~';
case '\'':
case '"':
return lexstring(J);
case '.':
return lexnumber(J);
case '<':
jsY_next(J);
if (jsY_accept(J, '<')) {
if (jsY_accept(J, '='))
return TK_SHL_ASS;
return TK_SHL;
}
if (jsY_accept(J, '='))
return TK_LE;
return '<';
case '>':
jsY_next(J);
if (jsY_accept(J, '>')) {
if (jsY_accept(J, '>')) {
if (jsY_accept(J, '='))
return TK_USHR_ASS;
return TK_USHR;
}
if (jsY_accept(J, '='))
return TK_SHR_ASS;
return TK_SHR;
}
if (jsY_accept(J, '='))
return TK_GE;
return '>';
case '=':
jsY_next(J);
if (jsY_accept(J, '=')) {
if (jsY_accept(J, '='))
return TK_STRICTEQ;
return TK_EQ;
}
return '=';
case '!':
jsY_next(J);
if (jsY_accept(J, '=')) {
if (jsY_accept(J, '='))
return TK_STRICTNE;
return TK_NE;
}
return '!';
case '+':
jsY_next(J);
if (jsY_accept(J, '+'))
return TK_INC;
if (jsY_accept(J, '='))
return TK_ADD_ASS;
return '+';
case '-':
jsY_next(J);
if (jsY_accept(J, '-'))
return TK_DEC;
if (jsY_accept(J, '='))
return TK_SUB_ASS;
return '-';
case '*':
jsY_next(J);
if (jsY_accept(J, '='))
return TK_MUL_ASS;
return '*';
case '%':
jsY_next(J);
if (jsY_accept(J, '='))
return TK_MOD_ASS;
return '%';
case '&':
jsY_next(J);
if (jsY_accept(J, '&'))
return TK_AND;
if (jsY_accept(J, '='))
return TK_AND_ASS;
return '&';
case '|':
jsY_next(J);
if (jsY_accept(J, '|'))
return TK_OR;
if (jsY_accept(J, '='))
return TK_OR_ASS;
return '|';
case '^':
jsY_next(J);
if (jsY_accept(J, '='))
return TK_XOR_ASS;
return '^';
case 0:
return 0; /* EOF */
}
/* Handle \uXXXX escapes in identifiers */
jsY_unescape(J);
if (jsY_isidentifierstart(J->lexchar)) {
textinit(J);
textpush(J, J->lexchar);
jsY_next(J);
jsY_unescape(J);
while (jsY_isidentifierpart(J->lexchar)) {
textpush(J, J->lexchar);
jsY_next(J);
jsY_unescape(J);
}
textend(J);
return jsY_findkeyword(J, J->lexbuf.text);
}
if (J->lexchar >= 0x20 && J->lexchar <= 0x7E)
jsY_error(J, "unexpected character: '%c'", J->lexchar);
jsY_error(J, "unexpected character: \\u%04X", J->lexchar);
}
}
void jsY_initlex(js_State *J, const char *filename, const char *source)
{
J->filename = filename;
J->source = source;
J->line = 1;
J->lasttoken = 0;
jsY_next(J); /* load first lookahead character */
}
int jsY_lex(js_State *J)
{
return J->lasttoken = jsY_lexx(J);
}
int jsY_lexjson(js_State *J)
{
while (1) {
J->lexline = J->line; /* save location of beginning of token */
while (jsY_iswhite(J->lexchar) || J->lexchar == '\n')
jsY_next(J);
if (J->lexchar >= '0' && J->lexchar <= '9') {
return lexnumber(J);
}
switch (J->lexchar) {
case ',': jsY_next(J); return ',';
case ':': jsY_next(J); return ':';
case '[': jsY_next(J); return '[';
case ']': jsY_next(J); return ']';
case '{': jsY_next(J); return '{';
case '}': jsY_next(J); return '}';
case '"':
return lexstring(J);
case '.':
return lexnumber(J);
case 'f':
jsY_next(J); jsY_expect(J, 'a'); jsY_expect(J, 'l'); jsY_expect(J, 's'); jsY_expect(J, 'e');
return TK_FALSE;
case 'n':
jsY_next(J); jsY_expect(J, 'u'); jsY_expect(J, 'l'); jsY_expect(J, 'l');
return TK_NULL;
case 't':
jsY_next(J); jsY_expect(J, 'r'); jsY_expect(J, 'u'); jsY_expect(J, 'e');
return TK_TRUE;
case 0:
return 0; /* EOF */
}
if (J->lexchar >= 0x20 && J->lexchar <= 0x7E)
jsY_error(J, "unexpected character: '%c'", J->lexchar);
jsY_error(J, "unexpected character: \\u%04X", J->lexchar);
}
}