ref: d457a43461852636db313c4854590b2c62a21e23
dir: /sys/src/cmd/gzip/unzip.c/
#include <u.h>
#include <libc.h>
#include <bio.h>
#include <flate.h>
#include "zip.h"
enum
{
BufSize = 4096
};
static int cheader(Biobuf *bin, ZipHead *zh);
static int copyout(int ofd, Biobuf *bin, long len);
static int crcwrite(void *ofd, void *buf, int n);
static int findCDir(Biobuf *bin, char *file);
static int get1(Biobuf *b);
static int get2(Biobuf *b);
static ulong get4(Biobuf *b);
static char *getname(Biobuf *b, int len);
static int header(Biobuf *bin, ZipHead *zh);
static long msdos2time(int time, int date);
static int sunzip(Biobuf *bin);
static int sunztable(Biobuf *bin);
static void trailer(Biobuf *bin, ZipHead *zh);
static int unzip(Biobuf *bin, char *file);
static int unzipEntry(Biobuf *bin, ZipHead *czh);
static int unztable(Biobuf *bin, char *file);
static int wantFile(char *file);
static void *emalloc(ulong);
static void error(char*, ...);
#pragma varargck argpos error 1
static Biobuf bin;
static ulong crc;
static ulong *crctab;
static int debug;
static char *delfile;
static int lower;
static int nwant;
static ulong rlen;
static int settimes;
static int stdout;
static int verbose;
static char **want;
static int wbad;
static ulong wlen;
static jmp_buf zjmp;
static jmp_buf seekjmp;
static int autodir;
static void
usage(void)
{
fprint(2, "usage: unzip [-acistTvD] [-f zipfile] [file ...]\n");
exits("usage");
}
void
main(int argc, char *argv[])
{
char *zfile;
int fd, ok, table, stream;
table = 0;
stream = 0;
zfile = nil;
ARGBEGIN{
case 'a':
autodir++;
break;
case 'D':
debug++;
break;
case 'c':
stdout++;
break;
case 'i':
lower++;
break;
case 'f':
zfile = ARGF();
if(zfile == nil)
usage();
break;
case 's':
stream++;
break;
case 't':
table++;
break;
case 'T':
settimes++;
break;
case 'v':
verbose++;
break;
default:
usage();
break;
}ARGEND
nwant = argc;
want = argv;
crctab = mkcrctab(ZCrcPoly);
ok = inflateinit();
if(ok != FlateOk)
sysfatal("inflateinit failed: %s", flateerr(ok));
if(zfile == nil){
Binit(&bin, 0, OREAD);
zfile = "<stdin>";
}else{
fd = open(zfile, OREAD);
if(fd < 0)
sysfatal("can't open %s: %r", zfile);
Binit(&bin, fd, OREAD);
}
if(setjmp(seekjmp)){
fprint(2, "trying to re-run assuming -s\n");
stream = 1;
Bseek(&bin, 0, 0);
}
if(table){
if(stream)
ok = sunztable(&bin);
else
ok = unztable(&bin, zfile);
}else{
if(stream)
ok = sunzip(&bin);
else
ok = unzip(&bin, zfile);
}
exits(ok ? nil: "errors");
}
/*
* print the table of contents from the "central directory structure"
*/
static int
unztable(Biobuf *bin, char *file)
{
ZipHead zh;
int entries;
entries = findCDir(bin, file);
if(entries < 0)
return 0;
if(verbose > 1)
print("%d items in the archive\n", entries);
while(entries-- > 0){
if(setjmp(zjmp)){
free(zh.file);
return 0;
}
memset(&zh, 0, sizeof(zh));
if(!cheader(bin, &zh))
return 1;
if(wantFile(zh.file)){
if(verbose)
print("%-32s %10lud %s", zh.file, zh.uncsize, ctime(msdos2time(zh.modtime, zh.moddate)));
else
print("%s\n", zh.file);
if(verbose > 1){
print("\tmade by os %d vers %d.%d\n", zh.madeos, zh.madevers/10, zh.madevers % 10);
print("\textract by os %d vers %d.%d\n", zh.extos, zh.extvers/10, zh.extvers % 10);
print("\tflags %x\n", zh.flags);
print("\tmethod %d\n", zh.meth);
print("\tmod time %d\n", zh.modtime);
print("\tmod date %d\n", zh.moddate);
print("\tcrc %lux\n", zh.crc);
print("\tcompressed size %lud\n", zh.csize);
print("\tuncompressed size %lud\n", zh.uncsize);
print("\tinternal attributes %ux\n", zh.iattr);
print("\texternal attributes %lux\n", zh.eattr);
print("\tstarts at %ld\n", zh.off);
}
}
free(zh.file);
zh.file = nil;
}
return 1;
}
/*
* print the "local file header" table of contents
*/
static int
sunztable(Biobuf *bin)
{
ZipHead zh;
vlong off;
ulong hcrc, hcsize, huncsize;
int ok, err;
ok = 1;
for(;;){
if(setjmp(zjmp)){
free(zh.file);
return 0;
}
memset(&zh, 0, sizeof(zh));
if(!header(bin, &zh))
return ok;
hcrc = zh.crc;
hcsize = zh.csize;
huncsize = zh.uncsize;
wlen = 0;
rlen = 0;
crc = 0;
wbad = 0;
if(zh.meth == 0){
if(!copyout(-1, bin, zh.csize))
error("reading data for %s failed: %r", zh.file);
}else if(zh.meth == 8){
off = Boffset(bin);
err = inflate((void*)-1, crcwrite, bin, (int(*)(void*))Bgetc);
if(err != FlateOk)
error("inflate %s failed: %s", zh.file, flateerr(err));
rlen = Boffset(bin) - off;
}else
error("can't handle compression method %d for %s", zh.meth, zh.file);
trailer(bin, &zh);
if(wantFile(zh.file)){
if(verbose)
print("%-32s %10lud %s", zh.file, zh.uncsize, ctime(msdos2time(zh.modtime, zh.moddate)));
else
print("%s\n", zh.file);
if(verbose > 1){
print("\textract by os %d vers %d.%d\n", zh.extos, zh.extvers / 10, zh.extvers % 10);
print("\tflags %x\n", zh.flags);
print("\tmethod %d\n", zh.meth);
print("\tmod time %d\n", zh.modtime);
print("\tmod date %d\n", zh.moddate);
print("\tcrc %lux\n", zh.crc);
print("\tcompressed size %lud\n", zh.csize);
print("\tuncompressed size %lud\n", zh.uncsize);
if((zh.flags & ZTrailInfo) && (hcrc || hcsize || huncsize)){
print("\theader crc %lux\n", zh.crc);
print("\theader compressed size %lud\n", zh.csize);
print("\theader uncompressed size %lud\n", zh.uncsize);
}
}
}
if(zh.crc != crc)
error("crc mismatch for %s", zh.file);
if(zh.uncsize != wlen)
error("output size mismatch for %s", zh.file);
if(zh.csize != rlen)
error("input size mismatch for %s", zh.file);
free(zh.file);
zh.file = nil;
}
}
/*
* extract files using the info in the central directory structure
*/
static int
unzip(Biobuf *bin, char *file)
{
ZipHead zh;
vlong off;
int ok, eok, entries;
entries = findCDir(bin, file);
if(entries < 0)
return 0;
ok = 1;
while(entries-- > 0){
if(setjmp(zjmp)){
free(zh.file);
return 0;
}
memset(&zh, 0, sizeof(zh));
if(!cheader(bin, &zh))
return ok;
off = Boffset(bin);
if(wantFile(zh.file)){
if(Bseek(bin, zh.off, 0) < 0){
fprint(2, "unzip: can't seek to start of %s, skipping\n", zh.file);
ok = 0;
}else{
eok = unzipEntry(bin, &zh);
if(eok <= 0){
fprint(2, "unzip: skipping %s\n", zh.file);
ok = 0;
}
}
}
free(zh.file);
zh.file = nil;
if(Bseek(bin, off, 0) < 0){
fprint(2, "unzip: can't seek to start of next entry, terminating extraction\n");
return 0;
}
}
return ok;
}
/*
* extract files using the info the "local file headers"
*/
static int
sunzip(Biobuf *bin)
{
int eok;
for(;;){
eok = unzipEntry(bin, nil);
if(eok == 0)
return 1;
if(eok < 0)
return 0;
}
}
static int mkdirs(char *);
/*
* if any directories leading up to path don't exist, create them.
* modifies but restores path.
*/
static int
mkpdirs(char *path)
{
int rv = 0;
char *sl = strrchr(path, '/');
print("%s\n", path);
if (sl != nil) {
*sl = '\0';
rv = mkdirs(path);
*sl = '/';
}
return rv;
}
/*
* if path or any directories leading up to it don't exist, create them.
* modifies but restores path.
*/
static int
mkdirs(char *path)
{
int fd;
if (access(path, AEXIST) >= 0)
return 0;
/* make presumed-missing intermediate directories */
if (mkpdirs(path) < 0)
return -1;
/* make final directory */
fd = create(path, OREAD, 0755|DMDIR);
if (fd < 0)
/*
* we may have lost a race; if the directory now exists,
* it's okay.
*/
return access(path, AEXIST) < 0? -1: 0;
close(fd);
return 0;
}
/*
* extracts a single entry from a zip file
* czh is the optional corresponding central directory entry
*/
static int
unzipEntry(Biobuf *bin, ZipHead *czh)
{
Dir *d;
ZipHead zh;
char *p;
vlong off;
int fd, isdir, ok, err;
zh.file = nil;
if(setjmp(zjmp)){
delfile = nil;
free(zh.file);
return -1;
}
memset(&zh, 0, sizeof(zh));
if(!header(bin, &zh))
return 0;
ok = 1;
isdir = 0;
fd = -1;
if(wantFile(zh.file)){
if(verbose)
fprint(2, "extracting %s\n", zh.file);
if(czh != nil && czh->extos == ZDos){
isdir = czh->eattr & ZDDir;
if(isdir && zh.uncsize != 0)
fprint(2, "unzip: ignoring directory data for %s\n", zh.file);
}
if(zh.meth == 0 && zh.uncsize == 0){
p = strchr(zh.file, '\0');
if(p > zh.file && p[-1] == '/')
isdir = 1;
}
if(stdout){
if(ok && !isdir)
fd = 1;
}else if(isdir){
fd = create(zh.file, OREAD, DMDIR | 0775);
if(fd < 0){
d = dirstat(zh.file);
if(d == nil || (d->mode & DMDIR) != DMDIR){
fprint(2, "unzip: can't create directory %s: %r\n", zh.file);
ok = 0;
}
free(d);
}
}else if(ok){
if(autodir)
mkpdirs(zh.file);
fd = create(zh.file, OWRITE, 0664);
if(fd < 0){
fprint(2, "unzip: can't create %s: %r\n", zh.file);
ok = 0;
}else
delfile = zh.file;
}
}
wlen = 0;
rlen = 0;
crc = 0;
wbad = 0;
if(zh.meth == 0){
if(!copyout(fd, bin, zh.csize))
error("copying data for %s failed: %r", zh.file);
}else if(zh.meth == 8){
off = Boffset(bin);
err = inflate((void*)fd, crcwrite, bin, (int(*)(void*))Bgetc);
if(err != FlateOk)
error("inflate failed: %s", flateerr(err));
rlen = Boffset(bin) - off;
}else
error("can't handle compression method %d for %s", zh.meth, zh.file);
trailer(bin, &zh);
if(zh.crc != crc)
error("crc mismatch for %s", zh.file);
if(zh.uncsize != wlen)
error("output size mismatch for %s", zh.file);
if(zh.csize != rlen)
error("input size mismatch for %s", zh.file);
delfile = nil;
free(zh.file);
if(fd >= 0 && !stdout){
if(settimes){
d = dirfstat(fd);
if(d != nil){
d->mtime = msdos2time(zh.modtime, zh.moddate);
if(d->mtime)
dirfwstat(fd, d);
}
}
close(fd);
}
return ok;
}
static int
wantFile(char *file)
{
int i, n;
if(nwant == 0)
return 1;
for(i = 0; i < nwant; i++){
if(strcmp(want[i], file) == 0)
return 1;
n = strlen(want[i]);
if(strncmp(want[i], file, n) == 0 && file[n] == '/')
return 1;
}
return 0;
}
/*
* find the start of the central directory
* returns the number of entries in the directory,
* or -1 if there was an error
*/
static int
findCDir(Biobuf *bin, char *file)
{
vlong ecoff;
long off, size;
int entries, zclen, dn, ds, de;
ecoff = Bseek(bin, -ZECHeadSize, 2);
if(ecoff < 0){
fprint(2, "unzip: can't seek to contents of %s\n", file);
longjmp(seekjmp, 1);
return -1;
}
if(setjmp(zjmp))
return -1;
off = 0;
while(get4(bin) != ZECHeader){
if(ecoff <= 0 || off >= 1024){
fprint(2, "unzip: cannot find end of table of contents in %s\n", file);
longjmp(seekjmp, 1);
return -1;
}
off++;
ecoff--;
Bseek(bin, ecoff, 0);
}
dn = get2(bin);
ds = get2(bin);
de = get2(bin);
entries = get2(bin);
size = get4(bin);
off = get4(bin);
zclen = get2(bin);
while(zclen-- > 0)
get1(bin);
if(verbose > 1){
print("table starts at %ld for %ld bytes\n", off, size);
if(ecoff - size != off)
print("\ttable should start at %lld-%ld=%lld\n", ecoff, size, ecoff-size);
if(dn || ds || de != entries)
print("\tcurrent disk=%d start disk=%d table entries on this disk=%d\n", dn, ds, de);
}
if(Bseek(bin, off, 0) != off){
fprint(2, "unzip: can't seek to start of contents of %s\n", file);
longjmp(seekjmp, 1);
return -1;
}
return entries;
}
static int
cheader(Biobuf *bin, ZipHead *zh)
{
ulong v;
int flen, xlen, fclen;
v = get4(bin);
if(v != ZCHeader){
if(v == ZECHeader)
return 0;
error("bad magic number %lux", v);
}
zh->madevers = get1(bin);
zh->madeos = get1(bin);
zh->extvers = get1(bin);
zh->extos = get1(bin);
zh->flags = get2(bin);
zh->meth = get2(bin);
zh->modtime = get2(bin);
zh->moddate = get2(bin);
zh->crc = get4(bin);
zh->csize = get4(bin);
zh->uncsize = get4(bin);
flen = get2(bin);
xlen = get2(bin);
fclen = get2(bin);
get2(bin); /* disk number start */
zh->iattr = get2(bin);
zh->eattr = get4(bin);
zh->off = get4(bin);
zh->file = getname(bin, flen);
while(xlen-- > 0)
get1(bin);
while(fclen-- > 0)
get1(bin);
return 1;
}
static int
header(Biobuf *bin, ZipHead *zh)
{
ulong v;
int flen, xlen;
v = get4(bin);
if(v != ZHeader){
if(v == ZCHeader)
return 0;
error("bad magic number %lux at %lld", v, Boffset(bin)-4);
}
zh->extvers = get1(bin);
zh->extos = get1(bin);
zh->flags = get2(bin);
zh->meth = get2(bin);
zh->modtime = get2(bin);
zh->moddate = get2(bin);
zh->crc = get4(bin);
zh->csize = get4(bin);
zh->uncsize = get4(bin);
flen = get2(bin);
xlen = get2(bin);
zh->file = getname(bin, flen);
while(xlen-- > 0)
get1(bin);
return 1;
}
static void
trailer(Biobuf *bin, ZipHead *zh)
{
if(zh->flags & ZTrailInfo){
zh->crc = get4(bin);
if(zh->crc == 0x08074b50) /* thanks apple */
zh->crc = get4(bin);
zh->csize = get4(bin);
zh->uncsize = get4(bin);
}
}
static char*
getname(Biobuf *bin, int len)
{
char *s;
int i, c;
s = emalloc(len + 1);
for(i = 0; i < len; i++){
c = get1(bin);
if(lower)
c = tolower(c);
s[i] = c;
}
s[i] = '\0';
return s;
}
static int
crcwrite(void *out, void *buf, int n)
{
int fd, nw;
wlen += n;
crc = blockcrc(crctab, crc, buf, n);
fd = (int)(uintptr)out;
if(fd < 0)
return n;
nw = write(fd, buf, n);
if(nw != n)
wbad = 1;
return nw;
}
static int
copyout(int ofd, Biobuf *bin, long len)
{
char buf[BufSize];
int n;
for(; len > 0; len -= n){
n = len;
if(n > BufSize)
n = BufSize;
n = Bread(bin, buf, n);
if(n <= 0)
return 0;
rlen += n;
if(crcwrite((void*)ofd, buf, n) != n)
return 0;
}
return 1;
}
static ulong
get4(Biobuf *b)
{
ulong v;
int i, c;
v = 0;
for(i = 0; i < 4; i++){
c = Bgetc(b);
if(c < 0)
error("unexpected eof reading file information");
v |= c << (i * 8);
}
return v;
}
static int
get2(Biobuf *b)
{
int i, c, v;
v = 0;
for(i = 0; i < 2; i++){
c = Bgetc(b);
if(c < 0)
error("unexpected eof reading file information");
v |= c << (i * 8);
}
return v;
}
static int
get1(Biobuf *b)
{
int c;
c = Bgetc(b);
if(c < 0)
error("unexpected eof reading file information");
return c;
}
static long
msdos2time(int time, int date)
{
Tm tm;
tm.hour = time >> 11;
tm.min = (time >> 5) & 63;
tm.sec = (time & 31) << 1;
tm.year = 80 + (date >> 9);
tm.mon = ((date >> 5) & 15) - 1;
tm.mday = date & 31;
tm.zone[0] = '\0';
tm.yday = 0;
return tm2sec(&tm);
}
static void*
emalloc(ulong n)
{
void *p;
p = malloc(n);
if(p == nil)
sysfatal("out of memory");
return p;
}
static void
error(char *fmt, ...)
{
va_list arg;
fprint(2, "unzip: ");
va_start(arg, fmt);
vfprint(2, fmt, arg);
va_end(arg);
fprint(2, "\n");
if(delfile != nil){
fprint(2, "unzip: removing output file %s\n", delfile);
remove(delfile);
delfile = nil;
}
longjmp(zjmp, 1);
}