ref: 34f5a8333090c5090e1d0b6ddbaf900d64340eea
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); }