4.2BSD/usr/src/bin/tar.c
#ifndef lint
static char *sccsid = "@(#)tar.c 4.19 (Berkeley) 9/22/83";
#endif
/*
* Tape Archival Program
*/
#include <stdio.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/dir.h>
#include <sys/ioctl.h>
#include <sys/mtio.h>
#include <sys/time.h>
#include <signal.h>
#include <errno.h>
#define TBLOCK 512
#define NBLOCK 20
#define NAMSIZ 100
union hblock {
char dummy[TBLOCK];
struct header {
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];
} dbuf;
};
struct linkbuf {
ino_t inum;
dev_t devnum;
int count;
char pathname[NAMSIZ];
struct linkbuf *nextp;
};
union hblock dblock;
union hblock *tbuf;
struct linkbuf *ihead;
struct stat stbuf;
int rflag;
int xflag;
int vflag;
int tflag;
int cflag;
int mflag;
int fflag;
int iflag;
int oflag;
int pflag;
int wflag;
int hflag;
int Bflag;
int Fflag;
int mt;
int term;
int chksum;
int recno;
int first;
int linkerrok;
int freemem = 1;
int nblock = NBLOCK;
int onintr();
int onquit();
int onhup();
int onterm();
daddr_t low;
daddr_t high;
daddr_t bsrch();
FILE *tfile;
char tname[] = "/tmp/tarXXXXXX";
char *usefile;
char magtape[] = "/dev/rmt8";
char *malloc();
char *sprintf();
char *strcat();
char *rindex();
char *getcwd();
char *getwd();
main(argc, argv)
int argc;
char *argv[];
{
char *cp;
if (argc < 2)
usage();
tfile = NULL;
usefile = magtape;
argv[argc] = 0;
argv++;
for (cp = *argv++; *cp; cp++)
switch(*cp) {
case 'f':
if (*argv == 0) {
fprintf(stderr,
"tar: tapefile must be specified with 'f' option\n");
usage();
}
usefile = *argv++;
fflag++;
break;
case 'c':
cflag++;
rflag++;
break;
case 'o':
oflag++;
break;
case 'p':
pflag++;
break;
case 'u':
mktemp(tname);
if ((tfile = fopen(tname, "w")) == NULL) {
fprintf(stderr,
"Tar: cannot create temporary file (%s)\n",
tname);
done(1);
}
fprintf(tfile, "!!!!!/!/!/!/!/!/!/! 000\n");
/*FALL THRU*/
case 'r':
rflag++;
break;
case 'v':
vflag++;
break;
case 'w':
wflag++;
break;
case 'x':
xflag++;
break;
case 't':
tflag++;
break;
case 'm':
mflag++;
break;
case '-':
break;
case '0':
case '1':
case '4':
case '5':
case '7':
case '8':
magtape[8] = *cp;
usefile = magtape;
break;
case 'b':
if (*argv == 0) {
fprintf(stderr,
"tar: blocksize must be specified with 'b' option\n");
usage();
}
nblock = atoi(*argv);
if (nblock <= 0) {
fprintf(stderr,
"tar: invalid blocksize \"%s\"\n", *argv);
done(1);
}
argv++;
break;
case 'l':
linkerrok++;
break;
case 'h':
hflag++;
break;
case 'i':
iflag++;
break;
case 'B':
Bflag++;
break;
case 'F':
Fflag++;
break;
default:
fprintf(stderr, "tar: %c: unknown option\n", *cp);
usage();
}
if (!rflag && !xflag && !tflag)
usage();
tbuf = (union hblock *)malloc(nblock*TBLOCK);
if (tbuf == NULL) {
fprintf(stderr, "tar: blocksize %d too big, can't get memory\n",
nblock);
done(1);
}
if (rflag) {
if (cflag && tfile != NULL)
usage();
if (signal(SIGINT, SIG_IGN) != SIG_IGN)
signal(SIGINT, onintr);
if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
signal(SIGHUP, onhup);
if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
signal(SIGQUIT, onquit);
#ifdef notdef
if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
signal(SIGTERM, onterm);
#endif
if (strcmp(usefile, "-") == 0) {
if (cflag == 0) {
fprintf(stderr,
"tar: can only create standard output archives\n");
done(1);
}
mt = dup(1);
nblock = 1;
} else if ((mt = open(usefile, 2)) < 0) {
if (cflag == 0 || (mt = creat(usefile, 0666)) < 0) {
fprintf(stderr,
"tar: cannot open %s\n", usefile);
done(1);
}
}
dorep(argv);
done(0);
}
if (strcmp(usefile, "-") == 0) {
mt = dup(0);
nblock = 1;
} else if ((mt = open(usefile, 0)) < 0) {
fprintf(stderr, "tar: cannot open %s\n", usefile);
done(1);
}
if (xflag)
doxtract(argv);
else
dotable();
done(0);
}
usage()
{
fprintf(stderr,
"tar: usage: tar -{txru}[cvfblmhopwBi] [tapefile] [blocksize] file1 file2...\n");
done(1);
}
dorep(argv)
char *argv[];
{
register char *cp, *cp2;
char wdir[MAXPATHLEN], tempdir[MAXPATHLEN], *parent;
if (!cflag) {
getdir();
do {
passtape();
if (term)
done(0);
getdir();
} while (!endtape());
backtape();
if (tfile != NULL) {
char buf[200];
sprintf(buf,
"sort +0 -1 +1nr %s -o %s; awk '$1 != prev {print; prev=$1}' %s >%sX; mv %sX %s",
tname, tname, tname, tname, tname, tname);
fflush(tfile);
system(buf);
freopen(tname, "r", tfile);
fstat(fileno(tfile), &stbuf);
high = stbuf.st_size;
}
}
(void) getcwd(wdir);
while (*argv && ! term) {
cp2 = *argv;
if (!strcmp(cp2, "-C") && argv[1]) {
argv++;
if (chdir(*argv) < 0)
perror(*argv);
else
(void) getcwd(wdir);
argv++;
continue;
}
parent = wdir;
for (cp = *argv; *cp; cp++)
if (*cp == '/')
cp2 = cp;
if (cp2 != *argv) {
*cp2 = '\0';
if (chdir(*argv) < 0) {
perror(*argv);
continue;
}
parent = getcwd(tempdir);
*cp2 = '/';
cp2++;
}
putfile(*argv++, cp2, parent);
if (chdir(wdir) < 0) {
fprintf(stderr, "cannot change back?: ");
perror(wdir);
}
}
putempty();
putempty();
flushtape();
if (linkerrok == 0)
return;
for (; ihead != NULL; ihead = ihead->nextp) {
if (ihead->count == 0)
continue;
fprintf(stderr, "tar: missing links to %s\n", ihead->pathname);
}
}
endtape()
{
return (dblock.dbuf.name[0] == '\0');
}
getdir()
{
register struct stat *sp;
int i;
top:
readtape((char *)&dblock);
if (dblock.dbuf.name[0] == '\0')
return;
sp = &stbuf;
sscanf(dblock.dbuf.mode, "%o", &i);
sp->st_mode = i;
sscanf(dblock.dbuf.uid, "%o", &i);
sp->st_uid = i;
sscanf(dblock.dbuf.gid, "%o", &i);
sp->st_gid = i;
sscanf(dblock.dbuf.size, "%lo", &sp->st_size);
sscanf(dblock.dbuf.mtime, "%lo", &sp->st_mtime);
sscanf(dblock.dbuf.chksum, "%o", &chksum);
if (chksum != (i = checksum())) {
fprintf(stderr, "tar: directory checksum error (%d != %d)\n",
chksum, i);
if (iflag)
goto top;
done(2);
}
if (tfile != NULL)
fprintf(tfile, "%s %s\n", dblock.dbuf.name, dblock.dbuf.mtime);
}
passtape()
{
long blocks;
char buf[TBLOCK];
if (dblock.dbuf.linkflag == '1')
return;
blocks = stbuf.st_size;
blocks += TBLOCK-1;
blocks /= TBLOCK;
while (blocks-- > 0)
readtape(buf);
}
putfile(longname, shortname, parent)
char *longname;
char *shortname;
char *parent;
{
int infile = 0;
long blocks;
char buf[TBLOCK];
register char *cp, *cp2;
struct direct *dp;
DIR *dirp;
int i, j;
char newparent[NAMSIZ+64];
extern int errno;
if (!hflag)
i = lstat(shortname, &stbuf);
else
i = stat(shortname, &stbuf);
if (i < 0) {
switch (errno) {
case EACCES:
fprintf(stderr, "tar: %s: cannot open file\n", longname);
break;
case ENOENT:
fprintf(stderr, "tar: %s: no such file or directory\n",
longname);
break;
default:
fprintf(stderr, "tar: %s: cannot stat file\n", longname);
break;
}
return;
}
if (tfile != NULL && checkupdate(longname) == 0)
return;
if (checkw('r', longname) == 0)
return;
if (Fflag && checkf(shortname, stbuf.st_mode, Fflag) == 0)
return;
switch (stbuf.st_mode & S_IFMT) {
case S_IFDIR:
for (i = 0, cp = buf; *cp++ = longname[i++];)
;
*--cp = '/';
*++cp = 0 ;
if (!oflag) {
if ((cp - buf) >= NAMSIZ) {
fprintf(stderr, "tar: %s: file name too long\n",
longname);
return;
}
stbuf.st_size = 0;
tomodes(&stbuf);
strcpy(dblock.dbuf.name,buf);
sprintf(dblock.dbuf.chksum, "%6o", checksum());
writetape((char *)&dblock);
}
sprintf(newparent, "%s/%s", parent, shortname);
if (chdir(shortname) < 0) {
perror(shortname);
return;
}
if ((dirp = opendir(".")) == NULL) {
fprintf(stderr, "tar: %s: directory read error\n",
longname);
if (chdir(parent) < 0) {
fprintf(stderr, "cannot change back?: ");
perror(parent);
}
return;
}
while ((dp = readdir(dirp)) != NULL && !term) {
if (dp->d_ino == 0)
continue;
if (!strcmp(".", dp->d_name) ||
!strcmp("..", dp->d_name))
continue;
strcpy(cp, dp->d_name);
i = telldir(dirp);
closedir(dirp);
putfile(buf, cp, newparent);
dirp = opendir(".");
seekdir(dirp, i);
}
closedir(dirp);
if (chdir(parent) < 0) {
fprintf(stderr, "cannot change back?: ");
perror(parent);
}
break;
case S_IFLNK:
tomodes(&stbuf);
if (strlen(longname) >= NAMSIZ) {
fprintf(stderr, "tar: %s: file name too long\n",
longname);
return;
}
strcpy(dblock.dbuf.name, longname);
if (stbuf.st_size + 1 >= NAMSIZ) {
fprintf(stderr, "tar: %s: symbolic link too long\n",
longname);
return;
}
i = readlink(shortname, dblock.dbuf.linkname, NAMSIZ - 1);
if (i < 0) {
perror(longname);
return;
}
dblock.dbuf.linkname[i] = '\0';
dblock.dbuf.linkflag = '2';
if (vflag) {
fprintf(stderr, "a %s ", longname);
fprintf(stderr, "symbolic link to %s\n",
dblock.dbuf.linkname);
}
sprintf(dblock.dbuf.size, "%11lo", 0);
sprintf(dblock.dbuf.chksum, "%6o", checksum());
writetape((char *)&dblock);
break;
case S_IFREG:
if ((infile = open(shortname, 0)) < 0) {
fprintf(stderr, "tar: %s: cannot open file\n", longname);
return;
}
tomodes(&stbuf);
if (strlen(longname) >= NAMSIZ) {
fprintf(stderr, "tar: %s: file name too long\n",
longname);
return;
}
strcpy(dblock.dbuf.name, longname);
if (stbuf.st_nlink > 1) {
struct linkbuf *lp;
int found = 0;
for (lp = ihead; lp != NULL; lp = lp->nextp)
if (lp->inum == stbuf.st_ino &&
lp->devnum == stbuf.st_dev) {
found++;
break;
}
if (found) {
strcpy(dblock.dbuf.linkname, lp->pathname);
dblock.dbuf.linkflag = '1';
sprintf(dblock.dbuf.chksum, "%6o", checksum());
writetape( (char *) &dblock);
if (vflag) {
fprintf(stderr, "a %s ", longname);
fprintf(stderr, "link to %s\n",
lp->pathname);
}
lp->count--;
close(infile);
return;
}
lp = (struct linkbuf *) malloc(sizeof(*lp));
if (lp == NULL) {
if (freemem) {
fprintf(stderr,
"tar: out of memory, link information lost\n");
freemem = 0;
}
} else {
lp->nextp = ihead;
ihead = lp;
lp->inum = stbuf.st_ino;
lp->devnum = stbuf.st_dev;
lp->count = stbuf.st_nlink - 1;
strcpy(lp->pathname, longname);
}
}
blocks = (stbuf.st_size + (TBLOCK-1)) / TBLOCK;
if (vflag) {
fprintf(stderr, "a %s ", longname);
fprintf(stderr, "%ld blocks\n", blocks);
}
sprintf(dblock.dbuf.chksum, "%6o", checksum());
writetape((char *)&dblock);
while ((i = read(infile, buf, TBLOCK)) > 0 && blocks > 0) {
writetape(buf);
blocks--;
}
close(infile);
if (blocks != 0 || i != 0)
fprintf(stderr, "tar: %s: file changed size\n",
longname);
while (--blocks >= 0)
putempty();
break;
default:
fprintf(stderr, "tar: %s is not a file. Not dumped\n",
longname);
break;
}
}
doxtract(argv)
char *argv[];
{
long blocks, bytes;
char buf[TBLOCK];
char **cp;
int ofile;
for (;;) {
getdir();
if (endtape())
break;
if (*argv == 0)
goto gotit;
for (cp = argv; *cp; cp++)
if (prefix(*cp, dblock.dbuf.name))
goto gotit;
passtape();
continue;
gotit:
if (checkw('x', dblock.dbuf.name) == 0) {
passtape();
continue;
}
if (Fflag) {
char *s;
if ((s = rindex(dblock.dbuf.name, '/')) == 0)
s = dblock.dbuf.name;
else
s++;
if (checkf(s, stbuf.st_mode, Fflag) == 0) {
passtape();
continue;
}
}
if (checkdir(dblock.dbuf.name))
continue;
if (dblock.dbuf.linkflag == '2') {
unlink(dblock.dbuf.name);
if (symlink(dblock.dbuf.linkname, dblock.dbuf.name)<0) {
fprintf(stderr, "tar: %s: symbolic link failed\n",
dblock.dbuf.name);
continue;
}
if (vflag)
fprintf(stderr, "x %s symbolic link to %s\n",
dblock.dbuf.name, dblock.dbuf.linkname);
#ifdef notdef
/* ignore alien orders */
chown(dblock.dbuf.name, stbuf.st_uid, stbuf.st_gid);
if (mflag == 0) {
struct timeval tv[2];
tv[0].tv_sec = time(0);
tv[0].tv_usec = 0;
tv[1].tv_sec = stbuf.st_mtime;
tv[1].tv_usec = 0;
utimes(dblock.dbuf.name, tv);
}
if (pflag)
chmod(dblock.dbuf.name, stbuf.st_mode & 07777);
#endif
continue;
}
if (dblock.dbuf.linkflag == '1') {
unlink(dblock.dbuf.name);
if (link(dblock.dbuf.linkname, dblock.dbuf.name) < 0) {
fprintf(stderr, "tar: %s: cannot link\n",
dblock.dbuf.name);
continue;
}
if (vflag)
fprintf(stderr, "%s linked to %s\n",
dblock.dbuf.name, dblock.dbuf.linkname);
continue;
}
if ((ofile = creat(dblock.dbuf.name,stbuf.st_mode&0xfff)) < 0) {
fprintf(stderr, "tar: %s - cannot create\n",
dblock.dbuf.name);
passtape();
continue;
}
chown(dblock.dbuf.name, stbuf.st_uid, stbuf.st_gid);
blocks = ((bytes = stbuf.st_size) + TBLOCK-1)/TBLOCK;
if (vflag)
fprintf(stderr, "x %s, %ld bytes, %ld tape blocks\n",
dblock.dbuf.name, bytes, blocks);
for (; blocks-- > 0; bytes -= TBLOCK) {
readtape(buf);
if (bytes > TBLOCK) {
if (write(ofile, buf, TBLOCK) < 0) {
fprintf(stderr,
"tar: %s: HELP - extract write error\n",
dblock.dbuf.name);
done(2);
}
continue;
}
if (write(ofile, buf, (int) bytes) < 0) {
fprintf(stderr,
"tar: %s: HELP - extract write error\n",
dblock.dbuf.name);
done(2);
}
}
close(ofile);
if (mflag == 0) {
struct timeval tv[2];
tv[0].tv_sec = time(0);
tv[0].tv_usec = 0;
tv[1].tv_sec = stbuf.st_mtime;
tv[1].tv_usec = 0;
utimes(dblock.dbuf.name, tv);
}
if (pflag)
chmod(dblock.dbuf.name, stbuf.st_mode & 07777);
}
}
dotable()
{
for (;;) {
getdir();
if (endtape())
break;
if (vflag)
longt(&stbuf);
printf("%s", dblock.dbuf.name);
if (dblock.dbuf.linkflag == '1')
printf(" linked to %s", dblock.dbuf.linkname);
if (dblock.dbuf.linkflag == '2')
printf(" symbolic link to %s", dblock.dbuf.linkname);
printf("\n");
passtape();
}
}
putempty()
{
char buf[TBLOCK];
bzero(buf, sizeof (buf));
writetape(buf);
}
longt(st)
register struct stat *st;
{
register char *cp;
char *ctime();
pmode(st);
printf("%3d/%1d", st->st_uid, st->st_gid);
printf("%7D", st->st_size);
cp = ctime(&st->st_mtime);
printf(" %-12.12s %-4.4s ", cp+4, cp+20);
}
#define SUID 04000
#define SGID 02000
#define ROWN 0400
#define WOWN 0200
#define XOWN 0100
#define RGRP 040
#define WGRP 020
#define XGRP 010
#define ROTH 04
#define WOTH 02
#define XOTH 01
#define STXT 01000
int m1[] = { 1, ROWN, 'r', '-' };
int m2[] = { 1, WOWN, 'w', '-' };
int m3[] = { 2, SUID, 's', XOWN, 'x', '-' };
int m4[] = { 1, RGRP, 'r', '-' };
int m5[] = { 1, WGRP, 'w', '-' };
int m6[] = { 2, SGID, 's', XGRP, 'x', '-' };
int m7[] = { 1, ROTH, 'r', '-' };
int m8[] = { 1, WOTH, 'w', '-' };
int m9[] = { 2, STXT, 't', XOTH, 'x', '-' };
int *m[] = { m1, m2, m3, m4, m5, m6, m7, m8, m9};
pmode(st)
register struct stat *st;
{
register int **mp;
for (mp = &m[0]; mp < &m[9];)
select(*mp++, st);
}
select(pairp, st)
int *pairp;
struct stat *st;
{
register int n, *ap;
ap = pairp;
n = *ap++;
while (--n>=0 && (st->st_mode&*ap++)==0)
ap++;
printf("%c", *ap);
}
checkdir(name)
register char *name;
{
register char *cp;
/*
* Quick check for existance of directory.
*/
if ((cp = rindex(name, '/')) == 0)
return (0);
*cp = '\0';
if (access(name, 0) >= 0) {
*cp = '/';
return (cp[1] == '\0');
}
*cp = '/';
/*
* No luck, try to make all directories in path.
*/
for (cp = name; *cp; cp++) {
if (*cp != '/')
continue;
*cp = '\0';
if (access(name, 0) < 0) {
if (mkdir(name, 0777) < 0) {
perror(name);
*cp = '/';
return (0);
}
chown(name, stbuf.st_uid, stbuf.st_gid);
if (pflag && cp[1] == '\0')
chmod(name, stbuf.st_mode & 0777);
}
*cp = '/';
}
return (cp[-1]=='/');
}
onintr()
{
signal(SIGINT, SIG_IGN);
term++;
}
onquit()
{
signal(SIGQUIT, SIG_IGN);
term++;
}
onhup()
{
signal(SIGHUP, SIG_IGN);
term++;
}
onterm()
{
signal(SIGTERM, SIG_IGN);
term++;
}
tomodes(sp)
register struct stat *sp;
{
register char *cp;
for (cp = dblock.dummy; cp < &dblock.dummy[TBLOCK]; cp++)
*cp = '\0';
sprintf(dblock.dbuf.mode, "%6o ", sp->st_mode & 07777);
sprintf(dblock.dbuf.uid, "%6o ", sp->st_uid);
sprintf(dblock.dbuf.gid, "%6o ", sp->st_gid);
sprintf(dblock.dbuf.size, "%11lo ", sp->st_size);
sprintf(dblock.dbuf.mtime, "%11lo ", sp->st_mtime);
}
checksum()
{
register i;
register char *cp;
for (cp = dblock.dbuf.chksum;
cp < &dblock.dbuf.chksum[sizeof(dblock.dbuf.chksum)]; cp++)
*cp = ' ';
i = 0;
for (cp = dblock.dummy; cp < &dblock.dummy[TBLOCK]; cp++)
i += *cp;
return (i);
}
checkw(c, name)
char *name;
{
if (!wflag)
return (1);
printf("%c ", c);
if (vflag)
longt(&stbuf);
printf("%s: ", name);
return (response() == 'y');
}
response()
{
char c;
c = getchar();
if (c != '\n')
while (getchar() != '\n')
;
else
c = 'n';
return (c);
}
checkf(name, mode, howmuch)
char *name;
int mode, howmuch;
{
int l;
if ((mode & S_IFMT) == S_IFDIR)
return (strcmp(name, "SCCS") != 0);
if ((l = strlen(name)) < 3)
return (1);
if (howmuch > 1 && name[l-2] == '.' && name[l-1] == 'o')
return (0);
if (strcmp(name, "core") == 0 ||
strcmp(name, "errs") == 0 ||
(howmuch > 1 && strcmp(name, "a.out") == 0))
return (0);
/* SHOULD CHECK IF IT IS EXECUTABLE */
return (1);
}
checkupdate(arg)
char *arg;
{
char name[100];
long mtime;
daddr_t seekp;
daddr_t lookup();
rewind(tfile);
for (;;) {
if ((seekp = lookup(arg)) < 0)
return (1);
fseek(tfile, seekp, 0);
fscanf(tfile, "%s %lo", name, &mtime);
return (stbuf.st_mtime > mtime);
}
}
done(n)
{
unlink(tname);
exit(n);
}
prefix(s1, s2)
register char *s1, *s2;
{
while (*s1)
if (*s1++ != *s2++)
return (0);
if (*s2)
return (*s2 == '/');
return (1);
}
#define N 200
int njab;
daddr_t
lookup(s)
char *s;
{
register i;
daddr_t a;
for(i=0; s[i]; i++)
if (s[i] == ' ')
break;
a = bsrch(s, i, low, high);
return (a);
}
daddr_t
bsrch(s, n, l, h)
daddr_t l, h;
char *s;
{
register i, j;
char b[N];
daddr_t m, m1;
njab = 0;
loop:
if (l >= h)
return (-1L);
m = l + (h-l)/2 - N/2;
if (m < l)
m = l;
fseek(tfile, m, 0);
fread(b, 1, N, tfile);
njab++;
for(i=0; i<N; i++) {
if (b[i] == '\n')
break;
m++;
}
if (m >= h)
return (-1L);
m1 = m;
j = i;
for(i++; i<N; i++) {
m1++;
if (b[i] == '\n')
break;
}
i = cmp(b+j, s, n);
if (i < 0) {
h = m;
goto loop;
}
if (i > 0) {
l = m1;
goto loop;
}
return (m);
}
cmp(b, s, n)
char *b, *s;
{
register i;
if (b[0] != '\n')
exit(2);
for(i=0; i<n; i++) {
if (b[i+1] > s[i])
return (-1);
if (b[i+1] < s[i])
return (1);
}
return (b[i+1] == ' '? 0 : -1);
}
readtape(buffer)
char *buffer;
{
register int i;
if (recno >= nblock || first == 0) {
if ((i = bread(mt, tbuf, TBLOCK*nblock)) < 0) {
fprintf(stderr, "tar: tape read error\n");
done(3);
}
if (first == 0) {
if ((i % TBLOCK) != 0) {
fprintf(stderr, "tar: tape blocksize error\n");
done(3);
}
i /= TBLOCK;
if (i != nblock) {
fprintf(stderr, "tar: blocksize = %d\n", i);
nblock = i;
}
}
recno = 0;
}
first = 1;
bcopy((char *)&tbuf[recno++], buffer, TBLOCK);
return (TBLOCK);
}
writetape(buffer)
char *buffer;
{
first = 1;
if (recno >= nblock) {
if (write(mt, tbuf, TBLOCK*nblock) < 0) {
fprintf(stderr, "tar: tape write error\n");
done(2);
}
recno = 0;
}
bcopy(buffer, (char *)&tbuf[recno++], TBLOCK);
if (recno >= nblock) {
if (write(mt, tbuf, TBLOCK*nblock) < 0) {
fprintf(stderr, "tar: tape write error\n");
done(2);
}
recno = 0;
}
return (TBLOCK);
}
backtape()
{
static int mtdev = 1;
static struct mtop mtop = {MTBSR, 1};
struct mtget mtget;
if (mtdev == 1)
mtdev = ioctl(mt, MTIOCGET, &mtget);
if (mtdev == 0) {
if (ioctl(mt, MTIOCTOP, &mtop) < 0) {
fprintf(stderr, "tar: tape backspace error\n");
done(4);
}
} else
lseek(mt, (long) -TBLOCK*nblock, 1);
recno--;
}
flushtape()
{
write(mt, tbuf, TBLOCK*nblock);
}
bread(fd, buf, size)
int fd;
char *buf;
int size;
{
int count;
static int lastread = 0;
if (!Bflag)
return (read(fd, buf, size));
for (count = 0; count < size; count += lastread) {
if (lastread < 0) {
if (count > 0)
return (count);
return (lastread);
}
lastread = read(fd, buf, size - count);
buf += lastread;
}
return (count);
}
char *
getcwd(buf)
char *buf;
{
if (getwd(buf) == NULL) {
fprintf(stderr, "tar: %s\n", buf);
exit(1);
}
return (buf);
}