aboutsummaryrefslogtreecommitdiff
path: root/src/cmd/gzip/unzip.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/cmd/gzip/unzip.c')
-rw-r--r--src/cmd/gzip/unzip.c740
1 files changed, 740 insertions, 0 deletions
diff --git a/src/cmd/gzip/unzip.c b/src/cmd/gzip/unzip.c
new file mode 100644
index 00000000..2f7888de
--- /dev/null
+++ b/src/cmd/gzip/unzip.c
@@ -0,0 +1,740 @@
+#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 void
+usage(void)
+{
+ fprint(2, "usage: unzip [-tsv] [-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 '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\n", 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(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;
+ }
+
+ return ok;
+}
+
+/*
+ * 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;
+ }
+
+ return 1;
+}
+
+/*
+ * 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){
+ 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; try adding -s\n", file);
+ return -1;
+ }
+ if(setjmp(zjmp))
+ return -1;
+
+ if(get4(bin) != ZECHeader){
+ fprint(2, "unzip: bad magic number for contents of %s\n", file);
+ return -1;
+ }
+ 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);
+ 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);
+ 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)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);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-01 10:06:05 +0000