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create.c
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1995-03-09
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/* Create a tar archive.
Copyright (C) 1988 Free Software Foundation
This file is part of GNU Tar.
GNU Tar is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 1, or (at your option)
any later version.
GNU Tar is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNU Tar; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
/*
* Create a tar archive.
*
* Written 25 Aug 1985 by John Gilmore, ihnp4!hoptoad!gnu.
*
* @(#)create.c 1.36 11/6/87 - gnu
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <stdio.h>
/* JF: this one is my fault */
/* #include "utils.h" */
#ifndef V7
#include <fcntl.h>
#endif
#if !defined(MSDOS) && !defined(AMIGA)
#include <pwd.h>
#include <grp.h>
#endif
#ifdef BSD42
#include <sys/dir.h>
#else
#ifdef MSDOS
#include <sys/dir.h>
#else
#ifdef USG
#ifdef NDIR
#include <ndir.h>
#else
#include <dirent.h>
#endif
#ifndef DIRECT
#define direct dirent
#endif
#define DP_NAMELEN(x) strlen((x)->d_name)
#else
/*
* FIXME: On other systems there is no standard place for the header file
* for the portable directory access routines. Change the #include line
* below to bring it in from wherever it is.
*/
#include "ndir.h"
#endif
#endif
#endif
#ifndef DP_NAMELEN
#define DP_NAMELEN(x) (x)->d_namlen
#endif
#ifdef USG
#include <sys/sysmacros.h> /* major() and minor() defined here */
#endif
/*
* V7 doesn't have a #define for this.
*/
#ifndef O_RDONLY
#define O_RDONLY 0
#endif
/*
* Most people don't have a #define for this.
*/
#ifndef O_BINARY
#define O_BINARY 0
#endif
#include "tar.h"
#include "port.h"
extern union record *head; /* Points to current tape header */
extern struct stat hstat; /* Stat struct corresponding */
extern int head_standard; /* Tape header is in ANSI format */
extern dev_t ar_dev;
extern ino_t ar_ino;
/* JF */
extern struct name *gnu_list_name;
/*
* If there are no symbolic links, there is no lstat(). Use stat().
*/
#ifndef S_IFLNK
#define lstat stat
#endif
extern char *malloc();
extern char *strcpy();
extern char *strncpy();
extern void bzero();
extern void bcopy();
extern int errno;
extern void print_header();
union record *start_header();
void finish_header();
void finduname();
void findgname();
char *name_next();
void to_oct();
void dump_file();
static nolinks; /* Gets set if we run out of RAM */
/*
* "Scratch" space to store the information about a sparse file before
* writing the info into the header or extended header
*/
/* struct sp_array *sparsearray;*/
/* number of elts storable in the sparsearray */
/*int sparse_array_size = 10;*/
void
create_archive()
{
register char *p;
char *name_from_list();
open_archive(0); /* Open for writing */
if(f_gnudump) {
char buf[MAXNAMLEN],*q,*bufp;
collect_and_sort_names();
while(p=name_from_list())
dump_file(p,-1);
/* if(!f_dironly) { */
blank_name_list();
while(p=name_from_list()) {
strcpy(buf,p);
#ifdef AMIGA
{
short len = strlen(p) - 1;
if (p[len] != '/' && p[len] != ':')
strcat(buf,"/");
}
#else
if(p[strlen(p)-1]!='/')
strcat(buf,"/");
#endif
bufp=buf+strlen(buf);
for(q=gnu_list_name->dir_contents;q && *q;q+=strlen(q)+1) {
if(*q=='Y') {
strcpy(bufp,q+1);
dump_file(buf,-1);
}
}
}
/* } */
} else {
p = name_next(1);
if(!p)
dump_file(".", -1);
else {
do dump_file(p, -1);
while (p = name_next(1));
}
}
write_eot();
close_archive();
name_close();
}
/*
* Dump a single file. If it's a directory, recurse.
* Result is 1 for success, 0 for failure.
* Sets global "hstat" to stat() output for this file.
*/
void
dump_file (p, curdev)
char *p; /* File name to dump */
int curdev; /* Device our parent dir was on */
{
union record *header;
char type;
extern char *save_name; /* JF for multi-volume support */
extern long save_totsize;
extern long save_sizeleft;
union record *exhdr;
char save_linkflag;
extern time_t new_time;
int sparse_ind = 0;
if(f_confirm && !confirm("add",p))
return;
/*
* Use stat if following (rather than dumping) 4.2BSD's
* symbolic links. Otherwise, use lstat (which, on non-4.2
* systems, is #define'd to stat anyway.
*/
if (0 != f_follow_links? stat(p, &hstat): lstat(p, &hstat))
{
badperror:
msg_perror("can't add file %s",p);
badfile:
errors++;
return;
}
/* See if we only want new files, and check if this one is too old to
put in the archive. */
if( f_new_files
&& !f_gnudump
&& new_time>hstat.st_mtime
&& (hstat.st_mode&S_IFMT)!=S_IFDIR
&& (f_new_files>1 || new_time>hstat.st_ctime)) {
if(curdev<0) {
msg("%s: is unchanged; not dumped",p);
}
return;
}
/*
* See if we are crossing from one file system to another,
* and avoid doing so if the user only wants to dump one file system.
*/
if (f_local_filesys && curdev >= 0 && curdev != hstat.st_dev) {
if(f_verbose)
msg("%s: is on a different filesystem; not dumped",p);
return;
}
/* See if we are trying to dump the archive */
if(ar_dev && hstat.st_dev==ar_dev && hstat.st_ino==ar_ino) {
msg("%s is the archive; not dumped",p);
return;
}
/*
* Check for multiple links.
*
* We maintain a list of all such files that we've written so
* far. Any time we see another, we check the list and
* avoid dumping the data again if we've done it once already.
*/
if (hstat.st_nlink > 1) switch (hstat.st_mode & S_IFMT) {
register struct link *lp;
case S_IFREG: /* Regular file */
#ifdef S_IFCTG
case S_IFCTG: /* Contigous file */
#endif
#ifdef S_IFCHR
case S_IFCHR: /* Character special file */
#endif
#ifdef S_IFBLK
case S_IFBLK: /* Block special file */
#endif
#ifdef S_IFIFO
case S_IFIFO: /* Fifo special file */
#endif
/* First quick and dirty. Hashing, etc later FIXME */
for (lp = linklist; lp; lp = lp->next) {
if (lp->ino == hstat.st_ino &&
lp->dev == hstat.st_dev) {
char *link_name = lp->name;
/* We found a link. */
hstat.st_size = 0;
header = start_header(p, &hstat);
if (header == NULL) goto badfile;
while(!f_absolute_paths && *link_name == '/') {
static int link_warn = 0;
if (!link_warn) {
msg("Removing leading / from absolute links");
link_warn++;
}
link_name++;
}
strcpy(header->header.linkname,
link_name);
header->header.linkflag = LF_LINK;
finish_header(header);
/* FIXME: Maybe remove from list after all links found? */
return; /* We dumped it */
}
}
/* Not found. Add it to the list of possible links. */
lp = (struct link *) malloc( (unsigned)
(strlen(p) + sizeof(struct link) - NAMSIZ));
if (!lp) {
if (!nolinks) {
msg(
"no memory for links, they will be dumped as separate files");
nolinks++;
}
}
lp->ino = hstat.st_ino;
lp->dev = hstat.st_dev;
strcpy(lp->name, p);
lp->next = linklist;
linklist = lp;
}
/*
* This is not a link to a previously dumped file, so dump it.
*/
switch (hstat.st_mode & S_IFMT) {
case S_IFREG: /* Regular file */
#ifdef S_IFCTG
case S_IFCTG: /* Contiguous file */
#endif
{
int f; /* File descriptor */
long bufsize, count;
long sizeleft;
register union record *start;
int header_moved;
char isextended = 0;
int upperbound;
int end_nulls = 0;
header_moved = 0;
#ifdef BSD42
if (f_sparse_files) {
/*
* JK - This is the test for sparseness: whether the
* "size" of the file matches the number of blocks
* allocated for it. If there is a smaller number
* of blocks that would be necessary to accommodate
* a file of this size, we have a sparse file, i.e.,
* at least one of those records in the file is just
* a useless hole.
*/
if (hstat.st_size - (hstat.st_blocks * RECORDSIZE) > RECORDSIZE) {
int filesize = hstat.st_size;
register int i;
printf("File is sparse: %s\n", p);
header = start_header(p, &hstat);
if (header == NULL)
goto badfile;
header->header.linkflag = LF_SPARSE;
header_moved++;
/*
* Call the routine that figures out the
* layout of the sparse file in question.
* UPPERBOUND is the index of the last
* element of the "sparsearray," i.e.,
* the number of elements it needed to
* describe the file.
*/
upperbound = deal_with_sparse(p, header);
/*
* See if we'll need an extended header
* later
*/
if (upperbound > SPARSE_IN_HDR-1)
header->header.isextended++;
/*
* We store the "real" file size so
* we can show that in case someone wants
* to list the archive, i.e., tar tvf <file>.
* It might be kind of disconcerting if the
* shrunken file size was the one that showed
* up.
*/
to_oct((long) hstat.st_size, 1+12,
header->header.realsize);
/*
* This will be the new "size" of the
* file, i.e., the size of the file
* minus the records of holes that we're
* skipping over.
*/
find_new_file_size(&filesize, upperbound);
printf("File %s is now size %d\n",
p, filesize);
hstat.st_size = filesize;
to_oct((long) filesize, 1+12,
header->header.size);
/* to_oct((long) end_nulls, 1+12,
header->header.ending_blanks);*/
for (i = 0; i < SPARSE_IN_HDR; i++) {
if (!sparsearray[i].numbytes)
break;
to_oct(sparsearray[i].offset, 1+12,
header->header.sp[i].offset);
to_oct(sparsearray[i].numbytes, 1+12,
header->header.sp[i].numbytes);
}
}
}
#else
upperbound=SPARSE_IN_HDR-1;
#endif
sizeleft = hstat.st_size;
/* Don't bother opening empty, world readable files. */
if (sizeleft > 0 || 0444 != (0444 & hstat.st_mode)) {
f = open(p, O_RDONLY|O_BINARY);
if (f < 0) goto badperror;
} else {
f = -1;
}
/* If the file is sparse, we've already taken care of this */
if (!header_moved) {
header = start_header(p, &hstat);
if (header == NULL) {
if(f>=0)
(void)close(f);
goto badfile;
}
}
#ifdef S_IFCTG
/* Mark contiguous files, if we support them */
if (f_standard && (hstat.st_mode & S_IFMT) == S_IFCTG) {
header->header.linkflag = LF_CONTIG;
}
#endif
isextended = header->header.isextended;
save_linkflag = header->header.linkflag;
finish_header(header);
if (isextended) {
int sum = 0;
register int i;
/* register union record *exhdr;*/
int arraybound = SPARSE_EXT_HDR;
/* static */ int index_offset = SPARSE_IN_HDR;
extend: exhdr = findrec();
if (exhdr == NULL) goto badfile;
bzero(exhdr->charptr, RECORDSIZE);
for (i = 0; i < SPARSE_EXT_HDR; i++) {
if (i+index_offset > upperbound)
break;
to_oct((long) sparsearray[i+index_offset].numbytes,
1+12,
exhdr->ext_hdr.sp[i].numbytes);
to_oct((long) sparsearray[i+index_offset].offset,
1+12,
exhdr->ext_hdr.sp[i].offset);
}
userec(exhdr);
/* sum += i;
if (sum < upperbound)
goto extend;*/
if (index_offset+i < upperbound) {
index_offset += i;
exhdr->ext_hdr.isextended++;
goto extend;
}
}
if (save_linkflag == LF_SPARSE) {
if (finish_sparse_file(f, &sizeleft, hstat.st_size, p))
goto padit;
}
else
while (sizeleft > 0) {
if(f_multivol) {
save_name = p;
save_sizeleft = sizeleft;
save_totsize = hstat.st_size;
}
start = findrec();
bufsize = endofrecs()->charptr - start->charptr;
if (sizeleft < bufsize) {
/* Last read -- zero out area beyond */
bufsize = (int)sizeleft;
count = bufsize % RECORDSIZE;
if (count)
bzero(start->charptr + sizeleft,
(int)(RECORDSIZE - count));
}
count = read(f, start->charptr, bufsize);
if (count < 0) {
msg_perror("read error at byte %ld, reading\
%d bytes, in file %s", hstat.st_size - sizeleft, bufsize,p);
goto padit;
}
sizeleft -= count;
/* This is nonportable (the type of userec's arg). */
userec(start+(count-1)/RECORDSIZE);
if (count == bufsize) continue;
msg( "file %s shrunk by %d bytes, padding with zeros.\n", p, sizeleft);
goto padit; /* Short read */
}
if(f_multivol)
save_name = 0;
if (f >= 0)
(void)close(f);
break;
/*
* File shrunk or gave error, pad out tape to match
* the size we specified in the header.
*/
padit:
while(sizeleft>0) {
save_sizeleft=sizeleft;
start=findrec();
bzero(start->charptr,RECORDSIZE);
userec(start);
sizeleft-=RECORDSIZE;
}
if(f_multivol)
save_name=0;
if(f>=0)
(void)close(f);
break;
/* abort(); */
}
#ifdef S_IFLNK
case S_IFLNK: /* Symbolic link */
{
int size;
hstat.st_size = 0; /* Force 0 size on symlink */
header = start_header(p, &hstat);
if (header == NULL) goto badfile;
size = readlink(p, header->header.linkname, NAMSIZ);
if (size < 0) goto badperror;
if (size == NAMSIZ) {
msg("symbolic link %s too long\n",p);
break;
}
header->header.linkname[size] = '\0';
header->header.linkflag = LF_SYMLINK;
finish_header(header); /* Nothing more to do to it */
}
break;
#endif
case S_IFDIR: /* Directory */
{
register DIR *dirp;
register struct direct *d;
static char namebuf[NAMSIZ+2];
register int len;
int our_device = hstat.st_dev;
/* Build new prototype name */
strncpy(namebuf, p, sizeof (namebuf));
len = strlen(namebuf);
while (len >= 1 && '/' == namebuf[len-1])
len--; /* Delete trailing slashes */
#ifdef AMIGA
if (len && namebuf[len-1] != ':')
namebuf[len++] = '/';
#else
namebuf[len++] = '/'; /* Now add exactly one back */
#endif
namebuf[len] = '\0'; /* Make sure null-terminated */
/*
* Output directory header record with permissions
* FIXME, do this AFTER files, to avoid R/O dir problems?
* If old archive format, don't write record at all.
*/
if (!f_oldarch) {
hstat.st_size = 0; /* Force 0 size on dir */
/*
* If people could really read standard archives,
* this should be: (FIXME)
header = start_header(f_standard? p: namebuf, &hstat);
* but since they'd interpret LF_DIR records as
* regular files, we'd better put the / on the name.
*/
header = start_header(namebuf, &hstat);
if (header == NULL)
goto badfile; /* eg name too long */
if (f_gnudump)
header->header.linkflag = LF_DUMPDIR;
else if (f_standard)
header->header.linkflag = LF_DIR;
/* If we're gnudumping, we aren't done yet so don't close it. */
if(!f_gnudump)
finish_header(header); /* Done with directory header */
}
/* Hack to remove "./" from the front of all the file names */
if (len == 2 && namebuf[0] == '.' && namebuf[1]=='/') {
len = 0;
}
if(f_gnudump) {
int sizeleft;
int totsize;
int bufsize;
union record *start;
int count;
char *buf,*p_buf;
buf=gnu_list_name->dir_contents; /* FOO */
totsize=0;
for(p_buf=buf;p_buf && *p_buf;) {
int tmp;
tmp=strlen(p_buf)+1;
totsize+=tmp;
p_buf+=tmp;
}
totsize++;
to_oct((long)totsize,1+12,header->header.size);
finish_header(header);
p_buf=buf;
sizeleft=totsize;
while(sizeleft>0) {
if(f_multivol) {
save_name=p;
save_sizeleft=sizeleft;
save_totsize=totsize;
}
start=findrec();
bufsize=endofrecs()->charptr - start->charptr;
if(sizeleft<bufsize) {
bufsize=sizeleft;
count=bufsize%RECORDSIZE;
if(count)
bzero(start->charptr+sizeleft,RECORDSIZE-count);
}
bcopy(p_buf,start->charptr,bufsize);
sizeleft-=bufsize;
p_buf+=bufsize;
userec(start+(bufsize-1)/RECORDSIZE);
}
if(f_multivol)
save_name = 0;
break;
}
/* Now output all the files in the directory */
/* if (f_dironly)
break; /* Unless the cmdline said not to */
errno = 0;
dirp = opendir(p);
if (!dirp) {
if (errno) {
msg_perror ("can't open directory %s",p);
} else {
msg("error opening directory %s",
p);
}
break;
}
/* Should speed this up by cd-ing into the dir, FIXME */
while (NULL != (d=readdir(dirp))) {
/* Skip . and .. */
if(is_dot_or_dotdot(d->d_name))
continue;
if (DP_NAMELEN(d) + len >= NAMSIZ) {
namebuf[len]='\0';
msg("file name %s%s too long\n",
namebuf, d->d_name);
continue;
}
strcpy(namebuf+len, d->d_name);
if(f_exclude && check_exclude(namebuf))
continue;
dump_file(namebuf, our_device);
}
closedir(dirp);
}
break;
#ifdef S_IFCHR
case S_IFCHR: /* Character special file */
type = LF_CHR;
goto easy;
#endif
#ifdef S_IFBLK
case S_IFBLK: /* Block special file */
type = LF_BLK;
goto easy;
#endif
#ifdef S_IFIFO
case S_IFIFO: /* Fifo special file */
type = LF_FIFO;
goto easy;
#endif
#ifdef S_IFSOCK
case S_IFSOCK: /* Socket pretend its a fifo? */
type = LF_FIFO;
goto easy;
#endif
easy:
if (!f_standard) goto unknown;
hstat.st_size = 0; /* Force 0 size */
header = start_header(p, &hstat);
if (header == NULL) goto badfile; /* eg name too long */
header->header.linkflag = type;
if (type != LF_FIFO) {
to_oct((long) major(hstat.st_rdev), 8,
header->header.devmajor);
to_oct((long) minor(hstat.st_rdev), 8,
header->header.devminor);
}
finish_header(header);
break;
default:
unknown:
msg("%s: Unknown file type; file ignored.\n", p);
break;
}
}
int
finish_sparse_file(fd, sizeleft, fullsize, name)
int fd;
long *sizeleft,
fullsize;
char *name;
{
union record *start;
static char tempbuf[RECORDSIZE];
int bufsize,
sparse_ind = 0,
count;
long pos;
while (*sizeleft > 0) {
start = findrec();
bzero(start->charptr, RECORDSIZE);
bufsize = sparsearray[sparse_ind].numbytes;
if (!bufsize) { /* we blew it, maybe */
msg("Wrote %ld of %ld bytes to file %s",
fullsize - *sizeleft, fullsize, name);
break;
}
pos = lseek(fd, sparsearray[sparse_ind++].offset, 0);
/*
* If the number of bytes to be written here exceeds
* the size of the temporary buffer, do it in steps.
*/
while (bufsize > RECORDSIZE) {
/* if (amt_read) {
count = read(fd, start->charptr+amt_read, RECORDSIZE-amt_read);
bufsize -= RECORDSIZE - amt_read;
amt_read = 0;
userec(start);
start = findrec();
bzero(start->charptr, RECORDSIZE);
}*/
/* store the data */
count = read(fd, start->charptr, RECORDSIZE);
if (count < 0) {
msg_perror("read error at byte %ld, reading %d bytes, in file %s",
fullsize - *sizeleft, bufsize, name);
return 1;
}
bufsize -= count;
*sizeleft -= count;
userec(start);
start = findrec();
bzero(start->charptr, RECORDSIZE);
}
clear_buffer(tempbuf);
count = read(fd, tempbuf, bufsize);
bcopy(tempbuf, start->charptr, RECORDSIZE);
if (count < 0) {
msg_perror("read error at byte %ld, reading %d bytes, in file %s",
fullsize - *sizeleft, bufsize, name);
return 1;
}
/* if (amt_read >= RECORDSIZE) {
amt_read = 0;
userec(start+(count-1)/RECORDSIZE);
if (count != bufsize) {
msg("file %s shrunk by %d bytes, padding with zeros.\n", name, sizeleft);
return 1;
}
start = findrec();
} else
amt_read += bufsize;*/
*sizeleft -= count;
userec(start);
}
free(sparsearray);
/* userec(start+(count-1)/RECORDSIZE);*/
return 0;
}
init_sparsearray()
{
register int i;
sp_array_size = 10;
/*
* Make room for our scratch space -- initially is 10 elts long
*/
sparsearray = (struct sp_array *) malloc(sp_array_size * sizeof(struct sp_array));
for (i = 0; i < sp_array_size; i++) {
sparsearray[i].offset = 0;
sparsearray[i].numbytes = 0;
}
}
/*
* Okay, we've got a sparse file on our hands -- now, what we need to do is
* make a pass through the file and carefully note where any data is, i.e.,
* we want to find how far into the file each instance of data is, and how
* many bytes are there. We store this information in the sparsearray,
* which will later be translated into header information. For now, we use
* the sparsearray as convenient storage.
*
* As a side note, this routine is a mess. If I could have found a cleaner
* way to do it, I would have. If anyone wants to find a nicer way to do
* this, feel free.
*/
int
deal_with_sparse(name, header, nulls_at_end)
char *name;
union record *header;
{
long numbytes = 0;
long offset = 0;
long save_offset;
int fd;
int start,
end;
int end_nulls = 0;
int current_size = hstat.st_size;
int sparse_ind = 0,
cc;
static char buf[RECORDSIZE];
int read_last_data = 0; /* did we just read the last record? */
int amidst_data = 0;
header->header.isextended = 0;
/*
* Can't open the file -- this problem will be caught later on,
* so just return.
*/
if ((fd = open(name, O_RDONLY)) < 0)
return;
init_sparsearray();
clear_buffer(buf);
while ((cc = read(fd, buf, sizeof buf)) != 0) {
if (sparse_ind > sp_array_size-1) {
/*
* realloc the scratch area, since we've run out of room --
*/
sparsearray = (struct sp_array *)
realloc(sparsearray,
2 * sp_array_size * (sizeof(struct sp_array)));
sp_array_size *= 2;
}
if (cc == sizeof buf) {
if (zero_record(buf)) {
if (amidst_data) {
sparsearray[sparse_ind++].numbytes
= numbytes;
amidst_data = 0;
numbytes = 0;
}
offset += cc;
} else { /* !zero_record(buf) */
if (!amidst_data) {
amidst_data = 1;
where_is_data(&start, &end, buf);
numbytes += end - start;
offset += start;
sparsearray[sparse_ind].offset = offset;
} else
numbytes += cc;
offset += cc;
}
} else if (cc < sizeof buf) {
if (!zero_record(buf)) {
if (!amidst_data) {
amidst_data = 1;
where_is_data(&start, &end, buf);
/* In case there are nulls at the
end that we need to remember */
if (end < cc)
end = cc;
numbytes += start - end;
offset += start;
/* end_nulls = RECORDSIZE - end;*/
} else {
numbytes += cc;
/* end_nulls = RECORDSIZE - end;*/
}
sparsearray[sparse_ind].numbytes = numbytes;
} /* else
end_nulls = cc;*/
}
clear_buffer(buf);
}
if (numbytes)
sparsearray[sparse_ind].numbytes = numbytes;
close(fd);
/* printf("%d\n", end_nulls);
*nulls_at_end = end_nulls;*/
return sparse_ind;
}
/*
* Just zeroes out the buffer so we don't confuse ourselves with leftover
* data.
*/
clear_buffer(buf)
char *buf;
{
register int i;
for (i = 0; i < RECORDSIZE; i++)
buf[i] = '\0';
}
/*
* JK -
* This routine takes a character array, and tells where within that array
* the data can be found. It skips over any zeros, and sets the first
* non-zero point in the array to be the "start", and continues until it
* finds non-data again, which is marked as the "end." This routine is
* mainly for 1) seeing how far into a file we must lseek to data, given
* that we have a sparse file, and 2) determining the "real size" of the
* file, i.e., the number of bytes in the sparse file that are data, as
* opposed to the zeros we are trying to skip.
*/
where_is_data(from, to, buffer)
int *from,
*to;
char *buffer;
{
register int i = 0;
register int save_to = *to;
int amidst_data = 0;
while (!buffer[i])
i++;
*from = i;
if (*from < 16) /* don't bother */
*from = 0;
/* keep going to make sure there isn't more real
data in this record */
while (i < RECORDSIZE) {
if (!buffer[i]) {
if (amidst_data) {
save_to = i;
amidst_data = 0;
}
i++;
}
else if (buffer[i]) {
if (!amidst_data)
amidst_data = 1;
i++;
}
}
if (i == RECORDSIZE)
*to = i;
else
*to = save_to;
}
/*
* Takes a recordful of data and basically cruises through it to see if
* it's made *entirely* of zeros, returning a 0 the instant it finds
* something that is a non-zero, i.e., useful data.
*/
zero_record(buffer)
char *buffer;
{
register int i;
for (i = 0; i < RECORDSIZE; i++)
if (buffer[i] != '\000')
return 0;
return 1;
}
find_new_file_size(filesize, highest_index)
int *filesize;
int highest_index;
{
register int i;
*filesize = 0;
for (i = 0; sparsearray[i].numbytes && i <= highest_index; i++)
*filesize += sparsearray[i].numbytes;
}
/*
* Make a header block for the file name whose stat info is st .
* Return header pointer for success, NULL if the name is too long.
*/
union record *
start_header(name, st)
char *name;
register struct stat *st;
{
register union record *header;
header = (union record *) findrec();
bzero(header->charptr, sizeof(*header)); /* XXX speed up */
/*
* Check the file name and put it in the record.
*/
if(!f_absolute_paths) {
static int warned_once = 0;
#ifdef MSDOS
if(name[1]==':') {
name+=2;
if(!warned_once++)
msg("Removing drive spec from names in the archive");
}
#endif
while ('/' == *name) {
name++; /* Force relative path */
if (!warned_once++)
msg("Removing leading / from absolute path names in the archive.");
}
}
strcpy(header->header.name, name);
if (header->header.name[NAMSIZ-1]) {
msg("%s: name too long\n", name);
return NULL;
}
to_oct((long) (st->st_mode & ~S_IFMT),
8, header->header.mode);
to_oct((long) st->st_uid, 8, header->header.uid);
to_oct((long) st->st_gid, 8, header->header.gid);
to_oct((long) st->st_size, 1+12, header->header.size);
to_oct((long) st->st_mtime, 1+12, header->header.mtime);
/* header->header.linkflag is left as null */
if(f_gnudump) {
to_oct((long) st->st_atime, 1+12, header->header.atime);
to_oct((long) st->st_ctime, 1+12, header->header.ctime);
}
#ifndef NONAMES
/* Fill in new Unix Standard fields if desired. */
if (f_standard) {
header->header.linkflag = LF_NORMAL; /* New default */
strcpy(header->header.magic, TMAGIC); /* Mark as Unix Std */
finduname(header->header.uname, st->st_uid);
findgname(header->header.gname, st->st_gid);
}
#endif
return header;
}
/*
* Finish off a filled-in header block and write it out.
* We also print the file name and/or full info if verbose is on.
*/
void
finish_header(header)
register union record *header;
{
register int i, sum;
register char *p;
void bcopy();
bcopy(CHKBLANKS, header->header.chksum, sizeof(header->header.chksum));
sum = 0;
p = header->charptr;
for (i = sizeof(*header); --i >= 0; ) {
/*
* We can't use unsigned char here because of old compilers,
* e.g. V7.
*/
sum += 0xFF & *p++;
}
/*
* Fill in the checksum field. It's formatted differently
* from the other fields: it has [6] digits, a null, then a
* space -- rather than digits, a space, then a null.
* We use to_oct then write the null in over to_oct's space.
* The final space is already there, from checksumming, and
* to_oct doesn't modify it.
*
* This is a fast way to do:
* (void) sprintf(header->header.chksum, "%6o", sum);
*/
to_oct((long) sum, 8, header->header.chksum);
header->header.chksum[6] = '\0'; /* Zap the space */
userec(header);
if (f_verbose) {
/* These globals are parameters to print_header, sigh */
head = header;
/* hstat is already set up */
head_standard = f_standard;
print_header();
}
return;
}
/*
* Quick and dirty octal conversion.
* Converts long "value" into a "digs"-digit field at "where",
* including a trailing space and room for a null. "digs"==3 means
* 1 digit, a space, and room for a null.
*
* We assume the trailing null is already there and don't fill it in.
* This fact is used by start_header and finish_header, so don't change it!
*
* This should be equivalent to:
* (void) sprintf(where, "%*lo ", digs-2, value);
* except that sprintf fills in the trailing null and we don't.
*/
void
to_oct(value, digs, where)
register long value;
register int digs;
register char *where;
{
--digs; /* Trailing null slot is left alone */
where[--digs] = ' '; /* Put in the space, though */
/* Produce the digits -- at least one */
do {
where[--digs] = '0' + (char)(value & 7); /* one octal digit */
value >>= 3;
} while (digs > 0 && value != 0);
/* Leading spaces, if necessary */
while (digs > 0)
where[--digs] = ' ';
}
/*
* Write the EOT record(s).
* We actually zero at least one record, through the end of the block.
* Old tar writes garbage after two zeroed records -- and PDtar used to.
*/
write_eot()
{
union record *p;
int bufsize;
void bzero();
p = findrec();
bufsize = endofrecs()->charptr - p->charptr;
bzero(p->charptr, bufsize);
userec(p);
}