BSD 4_3_Net_2 release
[unix-history] / usr / src / usr.bin / touch / touch.c
/*
* Copyright (c) 1988 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1988 Regents of the University of California.\n\
All rights reserved.\n";
#endif /* not lint */
#ifndef lint
static char sccsid[] = "@(#)touch.c 4.8 (Berkeley) 6/1/90";
#endif /* not lint */
/*
* Attempt to set the modify date of a file to the current date. If the
* file exists, read and write its first character. If the file doesn't
* exist, create it, unless -c option prevents it. If the file is read-only,
* -f forces chmod'ing and touch'ing.
*/
#include <sys/types.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <stdio.h>
static int dontcreate; /* set if -c option */
static int force; /* set if -f option */
main(argc, argv)
int argc;
char **argv;
{
extern int optind;
int ch, retval;
dontcreate = force = retval = 0;
while ((ch = getopt(argc, argv, "cf")) != EOF)
switch((char)ch) {
case 'c':
dontcreate = 1;
break;
case 'f':
force = 1;
break;
case '?':
default:
usage();
}
if (!*(argv += optind))
usage();
do {
retval |= touch(*argv);
} while (*++argv);
exit(retval);
}
touch(filename)
char *filename;
{
struct stat statbuffer;
if (stat(filename, &statbuffer) == -1) {
if (!dontcreate)
return(readwrite(filename, 0L));
fprintf(stderr, "touch: %s: does not exist\n", filename);
return(1);
}
if ((statbuffer.st_mode & S_IFMT) != S_IFREG) {
fprintf(stderr, "touch: %s: can only touch regular files\n",
filename);
return(1);
}
if (!access(filename, R_OK | W_OK))
return(readwrite(filename,statbuffer.st_size));
if (force) {
int retval;
if (chmod(filename, 0666)) {
fprintf(stderr, "touch: %s: couldn't chmod: ",
filename);
perror((char *)NULL);
return(1);
}
retval = readwrite(filename, statbuffer.st_size);
if (chmod(filename, statbuffer.st_mode)) {
fprintf(stderr, "touch: %s: couldn't chmod back: ",
filename);
perror((char *)NULL);
return(1);
}
return(retval);
}
fprintf(stderr, "touch: %s: cannot touch\n", filename);
return(1);
}
readwrite(filename, size)
char *filename;
off_t size;
{
int filedescriptor;
char first;
off_t lseek();
if (size) {
filedescriptor = open(filename, O_RDWR, 0);
if (filedescriptor == -1) {
error: fprintf(stderr, "touch: %s: ", filename);
perror((char *)NULL);
return(1);
}
if (read(filedescriptor, &first, 1) != 1)
goto error;
if (lseek(filedescriptor, 0L, 0) == -1)
goto error;
if (write(filedescriptor, &first, 1) != 1)
goto error;
} else {
filedescriptor = creat(filename, 0666);
if (filedescriptor == -1)
goto error;
}
if (close(filedescriptor) == -1)
goto error;
return(0);
}
usage()
{
fprintf(stderr, "usage: touch [-cf] file ...\n");
exit(1);
}