commit 1d620367bd070f2eae99a70f8537c701a737650a from: rsc date: Mon May 02 03:32:38 2005 UTC remove old tar commit - 4c00852c86097c9e96cb6f21a3a27a8be93306b2 commit + 1d620367bd070f2eae99a70f8537c701a737650a blob - 42bdcd412730b8c2a97af82c3b57ef9e3042987f (mode 644) blob + /dev/null --- src/cmd/tar.C +++ /dev/null @@ -1,859 +0,0 @@ -/* - * tar - `tape archiver', actually usable on any medium. - * POSIX "ustar" compliant when extracting, and by default when creating. - * this tar attempts to read and write multiple Tblock-byte blocks - * at once to and from the filesystem, and does not copy blocks - * around internally. - */ - -#include -#include -#include /* for %M */ -#include - -#define creat tar_creat - -/* - * modified versions of those in libc.h; scans only the first arg for - * keyletters and options. - */ -#define TARGBEGIN {\ - __fixargv0(); if(!argv0) argv0=*argv; \ - argv++, argc--; \ - if (argv[0]) {\ - char *_args, *_argt;\ - Rune _argc;\ - _args = &argv[0][0];\ - _argc = 0;\ - while(*_args && (_args += chartorune(&_argc, _args)))\ - switch(_argc) -#define TARGEND SET(_argt); USED(_argt); USED(_argc); USED(_args); argc--, argv++; } \ - USED(argv);USED(argc); } - -#define ROUNDUP(a, b) (((a) + (b) - 1)/(b)) -#define BYTES2TBLKS(bytes) ROUNDUP(bytes, Tblock) - -typedef vlong Off; -typedef char *(*Refill)(int ar, char *bufs); - -enum { Stdin, Stdout, Stderr }; -enum { None, Toc, Xtract, Replace }; -enum { - Tblock = 512, - Nblock = 40, /* maximum blocksize */ - Dblock = 20, /* default blocksize */ - Namsiz = 100, - Maxpfx = 155, /* from POSIX */ - Maxname = Namsiz + 1 + Maxpfx, - DEBUG = 0, -}; - -/* POSIX link flags */ -enum { - LF_PLAIN1 = '\0', - LF_PLAIN2 = '0', - LF_LINK = '1', - LF_SYMLINK1 = '2', - LF_SYMLINK2 = 's', - LF_CHR = '3', - LF_BLK = '4', - LF_DIR = '5', - LF_FIFO = '6', - LF_CONTIG = '7', - /* 'A' - 'Z' are reserved for custom implementations */ -}; - -#define islink(lf) (isreallink(lf) || issymlink(lf)) -#define isreallink(lf) ((lf) == LF_LINK) -#define issymlink(lf) ((lf) == LF_SYMLINK1 || (lf) == LF_SYMLINK2) - -typedef union { - char name[Namsiz]; - char mode[8]; - char uid[8]; - char gid[8]; - char size[12]; - char mtime[12]; - char chksum[8]; - char linkflag; - char linkname[Namsiz]; - - /* rest are defined by POSIX's ustar format; see p1003.2b */ - char magic[6]; /* "ustar" */ - char version[2]; - char uname[32]; - char gname[32]; - char devmajor[8]; - char devminor[8]; - char prefix[Maxpfx]; /* if non-null, path= prefix "/" name */ -} Hdr; - -int debug; -static int verb; -static int posix = 1; -static int creat; -static int aruid; -static int argid; -static int relative; -static int settime; -static int verbose; - -static int nblock = Dblock; -static char *usefile; -static char origdir[Maxname*2]; -static Hdr *tpblk, *endblk; -static Hdr *curblk; - -static void -usage(void) -{ - fprint(2, "usage: %s {txrc}[pPvRTugf] [archive] file1 file2...\n", - argv0); - exits("usage"); -} - -/* - * block-buffer management - */ - -static void -initblks(void) -{ - free(tpblk); - tpblk = malloc(Tblock * nblock); - assert(tpblk != nil); - endblk = tpblk + nblock; -} - -static char * -refill(int ar, char *bufs) -{ - int i, n; - unsigned bytes = Tblock * nblock; - static int done, first = 1; - - if (done) - return nil; - - /* try to size non-pipe input at first read */ - if (first && usefile) { - first = 0; - n = read(ar, bufs, bytes); - if (n <= 0) - sysfatal("error reading archive: %r"); - i = n; - if (i % Tblock != 0) { - fprint(2, "%s: archive block size (%d) error\n", - argv0, i); - exits("blocksize"); - } - i /= Tblock; - if (i != nblock) { - nblock = i; - fprint(2, "%s: blocking = %d\n", argv0, nblock); - endblk = (Hdr *)bufs + nblock; - bytes = n; - } - } else - n = readn(ar, bufs, bytes); - if (n == 0) - sysfatal("unexpected EOF reading archive"); - else if (n < 0) - sysfatal("error reading archive: %r"); - else if (n%Tblock != 0) - sysfatal("partial block read from archive"); - if (n != bytes) { - done = 1; - memset(bufs + n, 0, bytes - n); - } - return bufs; -} - -static Hdr * -getblk(int ar, Refill rfp) -{ - if (curblk == nil || curblk >= endblk) { /* input block exhausted? */ - if (rfp != nil && (*rfp)(ar, (char *)tpblk) == nil) - return nil; - curblk = tpblk; - } - return curblk++; -} - -static Hdr * -getblkrd(int ar) -{ - return getblk(ar, refill); -} - -static Hdr * -getblke(int ar) -{ - return getblk(ar, nil); -} - -static Hdr * -getblkz(int ar) -{ - Hdr *hp = getblke(ar); - - if (hp != nil) - memset(hp, 0, Tblock); - return hp; -} - -/* - * how many block buffers are available, starting at the address - * just returned by getblk*? - */ -static int -gothowmany(int max) -{ - int n = endblk - (curblk - 1); - - return n > max? max: n; -} - -/* - * indicate that one is done with the last block obtained from getblke - * and it is now available to be written into the archive. - */ -static void -putlastblk(int ar) -{ - unsigned bytes = Tblock * nblock; - - /* if writing end-of-archive, aid compression (good hygiene too) */ - if (curblk < endblk) - memset(curblk, 0, (char *)endblk - (char *)curblk); - if (write(ar, tpblk, bytes) != bytes) - sysfatal("error writing archive: %r"); -} - -static void -putblk(int ar) -{ - if (curblk >= endblk) - putlastblk(ar); -} - -static void -putbackblk(int ar) -{ - curblk--; - USED(ar); -} - -static void -putreadblks(int ar, int blks) -{ - curblk += blks - 1; - USED(ar); -} - -static void -putblkmany(int ar, int blks) -{ - curblk += blks - 1; - putblk(ar); -} - -/* - * common routines - */ - -/* modifies hp->chksum */ -long -chksum(Hdr *hp) -{ - int n = Tblock; - long i = 0; - uchar *cp = (uchar*)hp; - - memset(hp->chksum, ' ', sizeof hp->chksum); - while (n-- > 0) - i += *cp++; - return i; -} - -static int -isustar(Hdr *hp) -{ - return strcmp(hp->magic, "ustar") == 0; -} - -/* - * s is at most n bytes long, but need not be NUL-terminated. - * if shorter than n bytes, all bytes after the first NUL must also - * be NUL. - */ -static int -strnlen(char *s, int n) -{ - return s[n - 1] != '\0'? n: strlen(s); -} - -/* set fullname from header */ -static char * -name(Hdr *hp) -{ - int pfxlen, namlen; - static char fullname[Maxname + 1]; - - namlen = strnlen(hp->name, sizeof hp->name); - if (hp->prefix[0] == '\0' || !isustar(hp)) { /* old-style name? */ - memmove(fullname, hp->name, namlen); - fullname[namlen] = '\0'; - return fullname; - } - - /* name is in two pieces */ - pfxlen = strnlen(hp->prefix, sizeof hp->prefix); - memmove(fullname, hp->prefix, pfxlen); - fullname[pfxlen] = '/'; - memmove(fullname + pfxlen + 1, hp->name, namlen); - fullname[pfxlen + 1 + namlen] = '\0'; - return fullname; -} - -static int -isdir(Hdr *hp) -{ - /* the mode test is ugly but sometimes necessary */ - return hp->linkflag == LF_DIR || - strrchr(name(hp), '\0')[-1] == '/' || - (strtoul(hp->mode, nil, 8)&0170000) == 040000; -} - -static int -eotar(Hdr *hp) -{ - return name(hp)[0] == '\0'; -} - -static Hdr * -readhdr(int ar) -{ - long hdrcksum; - Hdr *hp; - - hp = getblkrd(ar); - if (hp == nil) - sysfatal("unexpected EOF instead of archive header"); - if (eotar(hp)) /* end-of-archive block? */ - return nil; - hdrcksum = strtoul(hp->chksum, nil, 8); - if (chksum(hp) != hdrcksum) - sysfatal("bad archive header checksum: name %.64s...", - hp->name); - return hp; -} - -/* - * tar r[c] - */ - -/* - * if name is longer than Namsiz bytes, try to split it at a slash and fit the - * pieces into hp->prefix and hp->name. - */ -static int -putfullname(Hdr *hp, char *name) -{ - int namlen, pfxlen; - char *sl, *osl; - String *slname = nil; - - if (isdir(hp)) { - slname = s_new(); - s_append(slname, name); - s_append(slname, "/"); /* posix requires this */ - name = s_to_c(slname); - } - - namlen = strlen(name); - if (namlen <= Namsiz) { - strncpy(hp->name, name, Namsiz); - hp->prefix[0] = '\0'; /* ustar paranoia */ - return 0; - } - - if (!posix || namlen > Maxname) { - fprint(2, "%s: name too long for tar header: %s\n", - argv0, name); - return -1; - } - /* - * try various splits until one results in pieces that fit into the - * appropriate fields of the header. look for slashes from right - * to left, in the hopes of putting the largest part of the name into - * hp->prefix, which is larger than hp->name. - */ - sl = strrchr(name, '/'); - while (sl != nil) { - pfxlen = sl - name; - if (pfxlen <= sizeof hp->prefix && namlen-1 - pfxlen <= Namsiz) - break; - osl = sl; - *osl = '\0'; - sl = strrchr(name, '/'); - *osl = '/'; - } - if (sl == nil) { - fprint(2, "%s: name can't be split to fit tar header: %s\n", - argv0, name); - return -1; - } - *sl = '\0'; - strncpy(hp->prefix, name, sizeof hp->prefix); - *sl++ = '/'; - strncpy(hp->name, sl, sizeof hp->name); - if (slname) - s_free(slname); - return 0; -} - -static int -mkhdr(Hdr *hp, Dir *dir, char *file) -{ - /* - * these fields run together, so we format them in order and don't use - * snprint. - */ - sprint(hp->mode, "%6lo ", dir->mode & 0777); - sprint(hp->uid, "%6o ", aruid); - sprint(hp->gid, "%6o ", argid); - /* - * files > 2⁳⁳ bytes can't be described - * (unless we resort to xustar or exustar formats). - */ - if (dir->length >= (Off)1<<33) { - fprint(2, "%s: %s: too large for tar header format\n", - argv0, file); - return -1; - } - sprint(hp->size, "%11lluo ", dir->length); - sprint(hp->mtime, "%11luo ", dir->mtime); - hp->linkflag = (dir->mode&DMDIR? LF_DIR: LF_PLAIN1); - putfullname(hp, file); - if (posix) { - strncpy(hp->magic, "ustar", sizeof hp->magic); - strncpy(hp->version, "00", sizeof hp->version); - strncpy(hp->uname, dir->uid, sizeof hp->uname); - strncpy(hp->gname, dir->gid, sizeof hp->gname); - } - sprint(hp->chksum, "%6luo", chksum(hp)); - return 0; -} - -static void addtoar(int ar, char *file, char *shortf); - -static void -addtreetoar(int ar, char *file, char *shortf, int fd) -{ - int n; - Dir *dent, *dirents; - String *name = s_new(); - - n = dirreadall(fd, &dirents); - close(fd); - if (n == 0) - return; - - if (chdir(shortf) < 0) - sysfatal("chdir %s: %r", file); - if (DEBUG) - fprint(2, "chdir %s\t# %s\n", shortf, file); - - for (dent = dirents; dent < dirents + n; dent++) { - s_reset(name); - s_append(name, file); - s_append(name, "/"); - s_append(name, dent->name); - addtoar(ar, s_to_c(name), dent->name); - } - s_free(name); - free(dirents); - - if (chdir("..") < 0) - sysfatal("chdir %s: %r", file); - if (DEBUG) - fprint(2, "chdir ..\n"); -} - -static void -addtoar(int ar, char *file, char *shortf) -{ - int n, fd, isdir, r; - long bytes; - ulong blksleft, blksread; - Hdr *hbp; - Dir *dir; - - fd = open(shortf, OREAD); - if (fd < 0) { - fprint(2, "%s: can't open %s: %r\n", argv0, file); - return; - } - dir = dirfstat(fd); - if (dir == nil) - sysfatal("can't fstat %s: %r", file); - - hbp = getblkz(ar); - isdir = !!(dir->qid.type&QTDIR); - r = mkhdr(hbp, dir, file); - if (r < 0) { - putbackblk(ar); - free(dir); - close(fd); - return; - } - putblk(ar); - - blksleft = BYTES2TBLKS(dir->length); - free(dir); - - if (isdir) - addtreetoar(ar, file, shortf, fd); - else { - for (; blksleft > 0; blksleft -= blksread) { - hbp = getblke(ar); - blksread = gothowmany(blksleft); - bytes = blksread * Tblock; - n = read(fd, hbp, bytes); - if (n < 0) - sysfatal("error reading %s: %r", file); - /* - * ignore EOF. zero any partial block to aid - * compression and emergency recovery of data. - */ - if (n < Tblock) - memset((char*)hbp + n, 0, bytes - n); - putblkmany(ar, blksread); - } - close(fd); - if (verbose) - fprint(2, "%s: a %s\n", argv0, file); - } -} - -static void -replace(char **argv) -{ - int i, ar; - ulong blksleft, blksread; - Off bytes; - Hdr *hp; - - if (usefile && creat) - ar = create(usefile, ORDWR, 0666); - else if (usefile) - ar = open(usefile, ORDWR); - else - ar = Stdout; - if (ar < 0) - sysfatal("can't open archive %s: %r", usefile); - - if (usefile && !creat) { - /* skip quickly to the end */ - while ((hp = readhdr(ar)) != nil) { - bytes = (isdir(hp)? 0: strtoull(hp->size, nil, 8)); - for (blksleft = BYTES2TBLKS(bytes); - blksleft > 0 && getblkrd(ar) != nil; - blksleft -= blksread) { - blksread = gothowmany(blksleft); - putreadblks(ar, blksread); - } - } - /* - * we have just read the end-of-archive Tblock. - * now seek back over the (big) archive block containing it, - * and back up curblk ptr over end-of-archive Tblock in memory. - */ - if (seek(ar, -Tblock*nblock, 1) < 0) - sysfatal("can't seek back over end-of-archive: %r"); - curblk--; - } - - for (i = 0; argv[i] != nil; i++) - addtoar(ar, argv[i], argv[i]); - - /* write end-of-archive marker */ - getblkz(ar); - putblk(ar); - getblkz(ar); - putlastblk(ar); - - if (ar > Stderr) - close(ar); -} - -/* - * tar [xt] - */ - -/* is pfx a file-name prefix of name? */ -static int -prefix(char *name, char *pfx) -{ - int pfxlen = strlen(pfx); - char clpfx[Maxname+1]; - - if (pfxlen > Maxname) - return 0; - strcpy(clpfx, pfx); - cleanname(clpfx); - return strncmp(pfx, name, pfxlen) == 0 && - (name[pfxlen] == '\0' || name[pfxlen] == '/'); -} - -static int -match(char *name, char **argv) -{ - int i; - char clname[Maxname+1]; - - if (argv[0] == nil) - return 1; - strcpy(clname, name); - cleanname(clname); - for (i = 0; argv[i] != nil; i++) - if (prefix(clname, argv[i])) - return 1; - return 0; -} - -static int -makedir(char *s) -{ - int f; - - if (access(s, AEXIST) == 0) - return -1; - f = create(s, OREAD, DMDIR | 0777); - if (f >= 0) - close(f); - return f; -} - -static void -mkpdirs(char *s) -{ - int done = 0; - char *p = s; - - while (!done && (p = strchr(p + 1, '/')) != nil) { - *p = '\0'; - done = (access(s, AEXIST) < 0 && makedir(s) < 0); - *p = '/'; - } -} - -/* copy a file from the archive into the filesystem */ -static void -extract1(int ar, Hdr *hp, char *fname) -{ - int wrbytes, fd = -1, dir = 0, okcreate = 1; - long mtime = strtol(hp->mtime, nil, 8); - ulong mode = strtoul(hp->mode, nil, 8) & 0777; - Off bytes = strtoll(hp->size, nil, 8); - ulong blksread, blksleft = BYTES2TBLKS(bytes); - Hdr *hbp; - - if (isdir(hp)) { - mode |= DMDIR|0700; - blksleft = 0; - dir = 1; - } - switch (hp->linkflag) { - case LF_LINK: - case LF_SYMLINK1: - case LF_SYMLINK2: - case LF_FIFO: - blksleft = okcreate = 0; - break; - } - if (relative && fname[0] == '/') - fname++; - if (verb == Xtract) { - cleanname(fname); - switch (hp->linkflag) { - case LF_LINK: - case LF_SYMLINK1: - case LF_SYMLINK2: - fprint(2, "%s: can't make (sym)link %s\n", - argv0, fname); - break; - case LF_FIFO: - fprint(2, "%s: can't make fifo %s\n", argv0, fname); - break; - } - if (okcreate) - fd = create(fname, (dir? OREAD: OWRITE), mode); - if (fd < 0) { - mkpdirs(fname); - fd = create(fname, (dir? OREAD: OWRITE), mode); - if (fd < 0 && (!dir || access(fname, AEXIST) < 0)) - fprint(2, "%s: can't create %s: %r\n", - argv0, fname); - } - if (fd >= 0 && verbose) - fprint(2, "%s: x %s\n", argv0, fname); - } else if (verbose) { - char *cp = ctime(mtime); - - print("%M %8lld %-12.12s %-4.4s %s\n", - mode, bytes, cp+4, cp+24, fname); - } else - print("%s\n", fname); - - for (; blksleft > 0; blksleft -= blksread) { - hbp = getblkrd(ar); - if (hbp == nil) - sysfatal("unexpected EOF on archive extracting %s", - fname); - blksread = gothowmany(blksleft); - wrbytes = (bytes >= Tblock*blksread? Tblock*blksread: bytes); - if (fd >= 0 && write(fd, (char*)hbp, wrbytes) != wrbytes) - sysfatal("write error on %s: %r", fname); - putreadblks(ar, blksread); - bytes -= wrbytes; - } - if (fd >= 0) { - /* - * directories should be wstated after we're done - * creating files in them. - */ - if (settime) { - Dir nd; - - nulldir(&nd); - nd.mtime = mtime; - if (isustar(hp)) - nd.gid = hp->gname; - dirfwstat(fd, &nd); - } - close(fd); - } -} - -static void -skip(int ar, Hdr *hp, char *fname) -{ - Off bytes; - ulong blksleft, blksread; - Hdr *hbp; - - if (isdir(hp)) - return; - bytes = strtoull(hp->size, nil, 8); - blksleft = BYTES2TBLKS(bytes); - for (; blksleft > 0; blksleft -= blksread) { - hbp = getblkrd(ar); - if (hbp == nil) - sysfatal("unexpected EOF on archive extracting %s", - fname); - blksread = gothowmany(blksleft); - putreadblks(ar, blksread); - } -} - -static void -extract(char **argv) -{ - int ar; - char *longname; - Hdr *hp; - - if (usefile) - ar = open(usefile, OREAD); - else - ar = Stdin; - if (ar < 0) - sysfatal("can't open archive %s: %r", usefile); - while ((hp = readhdr(ar)) != nil) { - longname = name(hp); - if (match(longname, argv)) - extract1(ar, hp, longname); - else - skip(ar, hp, longname); - } - if (ar > Stderr) - close(ar); -} - -void -main(int argc, char *argv[]) -{ - int errflg = 0; - char *ret = nil; - - quotefmtinstall(); - fmtinstall('M', dirmodefmt); - - TARGBEGIN { - case 'c': - creat++; - verb = Replace; - break; - case 'f': - usefile = EARGF(usage()); - break; - case 'g': - argid = strtoul(EARGF(usage()), 0, 0); - break; - case 'p': - posix++; - break; - case 'P': - posix = 0; - break; - case 'r': - verb = Replace; - break; - case 'R': - relative++; - break; - case 't': - verb = Toc; - break; - case 'T': - settime++; - break; - case 'u': - aruid = strtoul(EARGF(usage()), 0, 0); - break; - case 'v': - verbose++; - break; - case 'x': - verb = Xtract; - break; - case '-': - break; - default: - errflg++; - break; - } TARGEND - - if (argc < 0 || errflg) - usage(); - - initblks(); - switch (verb) { - case Toc: - case Xtract: - extract(argv); - break; - case Replace: - if (getwd(origdir, sizeof origdir) == nil) - strcpy(origdir, "/tmp"); - replace(argv); - chdir(origdir); /* for profiling */ - break; - default: - usage(); - break; - } - exits(ret); -}