Unofficial mirror of Fabrice Bellard's quickjs
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/*
* Javascript Compressor
*
* Copyright (c) 2008-2018 Fabrice Bellard
* Copyright (c) 2017-2018 Charlie Gordon
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdlib.h>
#include <stdio.h>
#include <getopt.h>
#include <stdarg.h>
#include <string.h>
#include <inttypes.h>
#include <unistd.h>
#include "cutils.h"
typedef struct JSToken {
int tok;
char buf[20];
char *str;
int len;
int size;
int line_num; /* line number for start of token */
int lines; /* number of embedded linefeeds in token */
} JSToken;
enum {
TOK_EOF = 256,
TOK_IDENT,
TOK_STR1,
TOK_STR2,
TOK_STR3,
TOK_NUM,
TOK_COM,
TOK_LCOM,
};
void tok_reset(JSToken *tt)
{
if (tt->str != tt->buf) {
free(tt->str);
tt->str = tt->buf;
tt->size = sizeof(tt->buf);
}
tt->len = 0;
}
void tok_add_ch(JSToken *tt, int c)
{
if (tt->len + 1 > tt->size) {
tt->size *= 2;
if (tt->str == tt->buf) {
tt->str = malloc(tt->size);
memcpy(tt->str, tt->buf, tt->len);
} else {
tt->str = realloc(tt->str, tt->size);
}
}
tt->str[tt->len++] = c;
}
FILE *infile;
const char *filename;
int output_line_num;
int line_num;
int ch;
JSToken tokc;
int skip_mask;
#define DEFINE_MAX 20
char *define_tab[DEFINE_MAX];
int define_len;
void error(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
if (filename) {
fprintf(stderr, "%s:%d: ", filename, line_num);
} else {
fprintf(stderr, "jscompress: ");
}
vfprintf(stderr, fmt, ap);
fprintf(stderr, "\n");
va_end(ap);
exit(1);
}
void define_symbol(const char *def)
{
int i;
for (i = 0; i < define_len; i++) {
if (!strcmp(tokc.str, define_tab[i]))
return;
}
if (define_len >= DEFINE_MAX)
error("too many defines");
define_tab[define_len++] = strdup(def);
}
void undefine_symbol(const char *def)
{
int i, j;
for (i = j = 0; i < define_len; i++) {
if (!strcmp(tokc.str, define_tab[i])) {
free(define_tab[i]);
} else {
define_tab[j++] = define_tab[i];
}
}
define_len = j;
}
const char *find_symbol(const char *def)
{
int i;
for (i = 0; i < define_len; i++) {
if (!strcmp(tokc.str, define_tab[i]))
return "1";
}
return NULL;
}
void next(void);
void nextch(void)
{
ch = fgetc(infile);
if (ch == '\n')
line_num++;
}
int skip_blanks(void)
{
for (;;) {
next();
if (tokc.tok != ' ' && tokc.tok != '\t' &&
tokc.tok != TOK_COM && tokc.tok != TOK_LCOM)
return tokc.tok;
}
}
void parse_directive(void)
{
int ifdef, mask = skip_mask;
/* simplistic preprocessor:
#define / #undef / #ifdef / #ifndef / #else / #endif
no symbol substitution.
*/
skip_mask = 0; /* disable skipping to parse preprocessor line */
nextch();
if (skip_blanks() != TOK_IDENT)
error("expected preprocessing directive after #");
if (!strcmp(tokc.str, "define")) {
if (skip_blanks() != TOK_IDENT)
error("expected identifier after #define");
define_symbol(tokc.str);
} else if (!strcmp(tokc.str, "undef")) {
if (skip_blanks() != TOK_IDENT)
error("expected identifier after #undef");
undefine_symbol(tokc.str);
} else if ((ifdef = 1, !strcmp(tokc.str, "ifdef")) ||
(ifdef = 0, !strcmp(tokc.str, "ifndef"))) {
if (skip_blanks() != TOK_IDENT)
error("expected identifier after #ifdef/#ifndef");
mask = (mask << 2) | 2 | ifdef;
if (find_symbol(tokc.str))
mask ^= 1;
} else if (!strcmp(tokc.str, "else")) {
if (!(mask & 2))
error("#else without a #if");
mask ^= 1;
} else if (!strcmp(tokc.str, "endif")) {
if (!(mask & 2))
error("#endif without a #if");
mask >>= 2;
} else {
error("unsupported preprocessing directive");
}
if (skip_blanks() != '\n')
error("extra characters on preprocessing line");
skip_mask = mask;
}
/* return -1 if invalid char */
static int hex_to_num(int ch)
{
if (ch >= 'a' && ch <= 'f')
return ch - 'a' + 10;
else if (ch >= 'A' && ch <= 'F')
return ch - 'A' + 10;
else if (ch >= '0' && ch <= '9')
return ch - '0';
else
return -1;
}
void next(void)
{
again:
tok_reset(&tokc);
tokc.line_num = line_num;
tokc.lines = 0;
switch(ch) {
case EOF:
tokc.tok = TOK_EOF;
if (skip_mask)
error("missing #endif");
break;
case 'a' ... 'z':
case 'A' ... 'Z':
case '_':
case '$':
tok_add_ch(&tokc, ch);
nextch();
while ((ch >= 'a' && ch <= 'z') ||
(ch >= 'A' && ch <= 'Z') ||
(ch >= '0' && ch <= '9') ||
(ch == '_' || ch == '$')) {
tok_add_ch(&tokc, ch);
nextch();
}
tok_add_ch(&tokc, '\0');
tokc.tok = TOK_IDENT;
break;
case '.':
nextch();
if (ch >= '0' && ch <= '9') {
tok_add_ch(&tokc, '.');
goto has_dot;
}
tokc.tok = '.';
break;
case '0':
tok_add_ch(&tokc, ch);
nextch();
if (ch == 'x' || ch == 'X') {
/* hexa */
tok_add_ch(&tokc, ch);
nextch();
while ((ch >= 'a' && ch <= 'f') ||
(ch >= 'A' && ch <= 'F') ||
(ch >= '0' && ch <= '9')) {
tok_add_ch(&tokc, ch);
nextch();
}
tok_add_ch(&tokc, '\0');
tokc.tok = TOK_NUM;
break;
}
goto has_digit;
case '1' ... '9':
tok_add_ch(&tokc, ch);
nextch();
has_digit:
/* decimal */
while (ch >= '0' && ch <= '9') {
tok_add_ch(&tokc, ch);
nextch();
}
if (ch == '.') {
tok_add_ch(&tokc, ch);
nextch();
has_dot:
while (ch >= '0' && ch <= '9') {
tok_add_ch(&tokc, ch);
nextch();
}
}
if (ch == 'e' || ch == 'E') {
tok_add_ch(&tokc, ch);
nextch();
if (ch == '+' || ch == '-') {
tok_add_ch(&tokc, ch);
nextch();
}
while (ch >= '0' && ch <= '9') {
tok_add_ch(&tokc, ch);
nextch();
}
}
tok_add_ch(&tokc, '\0');
tokc.tok = TOK_NUM;
break;
case '`':
{
nextch();
while (ch != '`' && ch != EOF) {
if (ch == '\\') {
tok_add_ch(&tokc, ch);
nextch();
if (ch == EOF) {
error("unexpected char after '\\'");
}
tok_add_ch(&tokc, ch);
} else {
tok_add_ch(&tokc, ch);
nextch();
}
}
nextch();
tok_add_ch(&tokc, 0);
tokc.tok = TOK_STR3;
}
break;
case '\"':
case '\'':
{
int n, i, c, hex_digit_count;
int quote_ch;
quote_ch = ch;
nextch();
while (ch != quote_ch && ch != EOF) {
if (ch == '\\') {
nextch();
switch(ch) {
case 'n':
tok_add_ch(&tokc, '\n');
nextch();
break;
case 'r':
tok_add_ch(&tokc, '\r');
nextch();
break;
case 't':
tok_add_ch(&tokc, '\t');
nextch();
break;
case 'v':
tok_add_ch(&tokc, '\v');
nextch();
break;
case '\"':
case '\'':
case '\\':
tok_add_ch(&tokc, ch);
nextch();
break;
case '0' ... '7':
n = 0;
while (ch >= '0' && ch <= '7') {
n = n * 8 + (ch - '0');
nextch();
}
tok_add_ch(&tokc, n);
break;
case 'x':
case 'u':
if (ch == 'x')
hex_digit_count = 2;
else
hex_digit_count = 4;
nextch();
n = 0;
for(i = 0; i < hex_digit_count; i++) {
c = hex_to_num(ch);
if (c < 0)
error("unexpected char after '\\x'");
n = n * 16 + c;
nextch();
}
if (n >= 256)
error("unicode is currently unsupported");
tok_add_ch(&tokc, n);
break;
default:
error("unexpected char after '\\'");
}
} else {
/* XXX: should refuse embedded newlines */
tok_add_ch(&tokc, ch);
nextch();
}
}
nextch();
tok_add_ch(&tokc, 0);
if (quote_ch == '\'')
tokc.tok = TOK_STR1;
else
tokc.tok = TOK_STR2;
}
break;
case '/':
nextch();
if (ch == '/') {
tok_add_ch(&tokc, '/');
tok_add_ch(&tokc, ch);
nextch();
while (ch != '\n' && ch != EOF) {
tok_add_ch(&tokc, ch);
nextch();
}
tok_add_ch(&tokc, '\0');
tokc.tok = TOK_LCOM;
} else if (ch == '*') {
int last;
tok_add_ch(&tokc, '/');
tok_add_ch(&tokc, ch);
last = 0;
for(;;) {
nextch();
if (ch == EOF)
error("unterminated comment");
if (ch == '\n')
tokc.lines++;
tok_add_ch(&tokc, ch);
if (last == '*' && ch == '/')
break;
last = ch;
}
nextch();
tok_add_ch(&tokc, '\0');
tokc.tok = TOK_COM;
} else {
tokc.tok = '/';
}
break;
case '#':
parse_directive();
goto again;
case '\n':
/* adjust line number */
tokc.line_num--;
tokc.lines++;
/* fall thru */
default:
tokc.tok = ch;
nextch();
break;
}
if (skip_mask & 1)
goto again;
}
void print_tok(FILE *f, JSToken *tt)
{
/* keep output lines in sync with input lines */
while (output_line_num < tt->line_num) {
putc('\n', f);
output_line_num++;
}
switch(tt->tok) {
case TOK_IDENT:
case TOK_COM:
case TOK_LCOM:
fprintf(f, "%s", tt->str);
break;
case TOK_NUM:
{
unsigned long a;
char *p;
a = strtoul(tt->str, &p, 0);
if (*p == '\0' && a <= 0x7fffffff) {
/* must be an integer */
fprintf(f, "%d", (int)a);
} else {
fprintf(f, "%s", tt->str);
}
}
break;
case TOK_STR3:
fprintf(f, "`%s`", tt->str);
break;
case TOK_STR1:
case TOK_STR2:
{
int i, c, quote_ch;
if (tt->tok == TOK_STR1)
quote_ch = '\'';
else
quote_ch = '\"';
fprintf(f, "%c", quote_ch);
for(i = 0; i < tt->len - 1; i++) {
c = (uint8_t)tt->str[i];
switch(c) {
case '\r':
fprintf(f, "\\r");
break;
case '\n':
fprintf(f, "\\n");
break;
case '\t':
fprintf(f, "\\t");
break;
case '\v':
fprintf(f, "\\v");
break;
case '\"':
case '\'':
if (c == quote_ch)
fprintf(f, "\\%c", c);
else
fprintf(f, "%c", c);
break;
case '\\':
fprintf(f, "\\\\");
break;
default:
/* XXX: no utf-8 support! */
if (c >= 32 && c <= 255) {
fprintf(f, "%c", c);
} else if (c <= 255)
fprintf(f, "\\x%02x", c);
else
fprintf(f, "\\u%04x", c);
break;
}
}
fprintf(f, "%c", quote_ch);
}
break;
default:
if (tokc.tok >= 256)
error("unsupported token in print_tok: %d", tt->tok);
fprintf(f, "%c", tt->tok);
break;
}
output_line_num += tt->lines;
}
/* check if token pasting could occur */
static BOOL compat_token(int c1, int c2)
{
if ((c1 == TOK_IDENT || c1 == TOK_NUM) &&
(c2 == TOK_IDENT || c2 == TOK_NUM))
return FALSE;
if ((c1 == c2 && strchr("+-<>&|=*/.", c1))
|| (c2 == '=' && strchr("+-<>&|!*/^%", c1))
|| (c1 == '=' && c2 == '>')
|| (c1 == '/' && c2 == '*')
|| (c1 == '.' && c2 == TOK_NUM)
|| (c1 == TOK_NUM && c2 == '.'))
return FALSE;
return TRUE;
}
void js_compress(const char *filename, const char *outfilename,
BOOL do_strip, BOOL keep_header)
{
FILE *outfile;
int ltok, seen_space;
line_num = 1;
infile = fopen(filename, "rb");
if (!infile) {
perror(filename);
exit(1);
}
output_line_num = 1;
outfile = fopen(outfilename, "wb");
if (!outfile) {
perror(outfilename);
exit(1);
}
nextch();
next();
ltok = 0;
seen_space = 0;
if (do_strip) {
if (keep_header) {
while (tokc.tok == ' ' ||
tokc.tok == '\n' ||
tokc.tok == '\t' ||
tokc.tok == '\v' ||
tokc.tok == '\b' ||
tokc.tok == '\f') {
seen_space = 1;
next();
}
if (tokc.tok == TOK_COM) {
print_tok(outfile, &tokc);
//fprintf(outfile, "\n");
ltok = tokc.tok;
seen_space = 0;
next();
}
}
for(;;) {
if (tokc.tok == TOK_EOF)
break;
if (tokc.tok == ' ' ||
tokc.tok == '\r' ||
tokc.tok == '\t' ||
tokc.tok == '\v' ||
tokc.tok == '\b' ||
tokc.tok == '\f' ||
tokc.tok == TOK_LCOM ||
tokc.tok == TOK_COM) {
/* don't print spaces or comments */
seen_space = 1;
} else if (tokc.tok == TOK_STR3) {
print_tok(outfile, &tokc);
ltok = tokc.tok;
seen_space = 0;
} else if (tokc.tok == TOK_STR1 || tokc.tok == TOK_STR2) {
int count, i;
/* find the optimal quote char */
count = 0;
for(i = 0; i < tokc.len; i++) {
if (tokc.str[i] == '\'')
count++;
else if (tokc.str[i] == '\"')
count--;
}
if (count > 0)
tokc.tok = TOK_STR2;
else if (count < 0)
tokc.tok = TOK_STR1;
print_tok(outfile, &tokc);
ltok = tokc.tok;
seen_space = 0;
} else {
if (seen_space && !compat_token(ltok, tokc.tok)) {
fprintf(outfile, " ");
}
print_tok(outfile, &tokc);
ltok = tokc.tok;
seen_space = 0;
}
next();
}
} else {
/* just handle preprocessing */
while (tokc.tok != TOK_EOF) {
print_tok(outfile, &tokc);
next();
}
}
fclose(outfile);
fclose(infile);
}
#define HASH_SIZE 30011
#define MATCH_LEN_MIN 3
#define MATCH_LEN_MAX (4 + 63)
#define DIST_MAX 65535
static int find_longest_match(int *pdist, const uint8_t *src, int src_len,
const int *hash_next, int cur_pos)
{
int pos, i, match_len, match_pos, pos_min, len_max;
len_max = min_int(src_len - cur_pos, MATCH_LEN_MAX);
match_len = 0;
match_pos = 0;
pos_min = max_int(cur_pos - DIST_MAX - 1, 0);
pos = hash_next[cur_pos];
while (pos >= pos_min) {
for(i = 0; i < len_max; i++) {
if (src[cur_pos + i] != src[pos + i])
break;
}
if (i > match_len) {
match_len = i;
match_pos = pos;
}
pos = hash_next[pos];
}
*pdist = cur_pos - match_pos - 1;
return match_len;
}
int lz_compress(uint8_t **pdst, const uint8_t *src, int src_len)
{
int *hash_table, *hash_next;
uint32_t h, v;
int i, dist, len, len1, dist1;
uint8_t *dst, *q;
/* build the hash table */
hash_table = malloc(sizeof(hash_table[0]) * HASH_SIZE);
for(i = 0; i < HASH_SIZE; i++)
hash_table[i] = -1;
hash_next = malloc(sizeof(hash_next[0]) * src_len);
for(i = 0; i < src_len; i++)
hash_next[i] = -1;
for(i = 0; i < src_len - MATCH_LEN_MIN + 1; i++) {
h = ((src[i] << 16) | (src[i + 1] << 8) | src[i + 2]) % HASH_SIZE;
hash_next[i] = hash_table[h];
hash_table[h] = i;
}
for(;i < src_len; i++) {
hash_next[i] = -1;
}
free(hash_table);
dst = malloc(src_len + 4); /* never larger than the source */
q = dst;
*q++ = src_len >> 24;
*q++ = src_len >> 16;
*q++ = src_len >> 8;
*q++ = src_len >> 0;
/* compress */
i = 0;
while (i < src_len) {
if (src[i] >= 128)
return -1;
len = find_longest_match(&dist, src, src_len, hash_next, i);
if (len >= MATCH_LEN_MIN) {
/* heuristic: see if better length just after */
len1 = find_longest_match(&dist1, src, src_len, hash_next, i + 1);
if (len1 > len)
goto no_match;
}
if (len < MATCH_LEN_MIN) {
no_match:
*q++ = src[i];
i++;
} else if (len <= (3 + 15) && dist < (1 << 10)) {
v = 0x8000 | ((len - 3) << 10) | dist;
*q++ = v >> 8;
*q++ = v;
i += len;
} else if (len >= 4 && len <= (4 + 63) && dist < (1 << 16)) {
v = 0xc00000 | ((len - 4) << 16) | dist;
*q++ = v >> 16;
*q++ = v >> 8;
*q++ = v;
i += len;
} else {
goto no_match;
}
}
free(hash_next);
*pdst = dst;
return q - dst;
}
static int load_file(uint8_t **pbuf, const char *filename)
{
FILE *f;
uint8_t *buf;
int buf_len;
f = fopen(filename, "rb");
if (!f) {
perror(filename);
exit(1);
}
fseek(f, 0, SEEK_END);
buf_len = ftell(f);
fseek(f, 0, SEEK_SET);
buf = malloc(buf_len + 1);
fread(buf, 1, buf_len, f);
buf[buf_len] = '\0';
fclose(f);
*pbuf = buf;
return buf_len;
}
static void save_file(const char *filename, const uint8_t *buf, int buf_len)
{
FILE *f;
f = fopen(filename, "wb");
if (!f) {
perror(filename);
exit(1);
}
fwrite(buf, 1, buf_len, f);
fclose(f);
}
static void save_c_source(const char *filename, const uint8_t *buf, int buf_len,
const char *var_name)
{
FILE *f;
int i;
f = fopen(filename, "wb");
if (!f) {
perror(filename);
exit(1);
}
fprintf(f, "/* This file is automatically generated - do not edit */\n\n");
fprintf(f, "const uint8_t %s[] = {\n", var_name);
for(i = 0; i < buf_len; i++) {
fprintf(f, " 0x%02x,", buf[i]);
if ((i % 8) == 7 || (i == buf_len - 1))
fprintf(f, "\n");
}
fprintf(f, "};\n");
fclose(f);
}
#define DEFAULT_OUTPUT_FILENAME "out.js"
void help(void)
{
printf("jscompress version 1.0 Copyright (c) 2008-2018 Fabrice Bellard\n"
"usage: jscompress [options] filename\n"
"Javascript compressor\n"
"\n"
"-h print this help\n"
"-n do not compress spaces\n"
"-H keep the first comment\n"
"-c compress to file\n"
"-C name compress to C source ('name' is the variable name)\n"
"-D symbol define preprocessor symbol\n"
"-U symbol undefine preprocessor symbol\n"
"-o outfile set the output filename (default=%s)\n",
DEFAULT_OUTPUT_FILENAME);
exit(1);
}
int main(int argc, char **argv)
{
int c, do_strip, keep_header, compress;
const char *out_filename, *c_var, *fname;
char tmpfilename[1024];
do_strip = 1;
keep_header = 0;
out_filename = DEFAULT_OUTPUT_FILENAME;
compress = 0;
c_var = NULL;
for(;;) {
c = getopt(argc, argv, "hno:HcC:D:U:");
if (c == -1)
break;
switch(c) {
case 'h':
help();
break;
case 'n':
do_strip = 0;
break;
case 'o':
out_filename = optarg;
break;
case 'H':
keep_header = 1;
break;
case 'c':
compress = 1;
break;
case 'C':
c_var = optarg;
compress = 1;
break;
case 'D':
define_symbol(optarg);
break;
case 'U':
undefine_symbol(optarg);
break;
}
}
if (optind >= argc)
help();
filename = argv[optind++];
if (compress) {
#if defined(__ANDROID__)
/* XXX: use another directory ? */
snprintf(tmpfilename, sizeof(tmpfilename), "out.%d", getpid());
#else
snprintf(tmpfilename, sizeof(tmpfilename), "/tmp/out.%d", getpid());
#endif
fname = tmpfilename;
} else {
fname = out_filename;
}
js_compress(filename, fname, do_strip, keep_header);
if (compress) {
uint8_t *buf1, *buf2;
int buf1_len, buf2_len;
buf1_len = load_file(&buf1, fname);
unlink(fname);
buf2_len = lz_compress(&buf2, buf1, buf1_len);
if (buf2_len < 0) {
fprintf(stderr, "Could not compress file (UTF8 chars are forbidden)\n");
exit(1);
}
if (c_var) {
save_c_source(out_filename, buf2, buf2_len, c_var);
} else {
save_file(out_filename, buf2, buf2_len);
}
free(buf1);
free(buf2);
}
return 0;
}