diff options
Diffstat (limited to 'usr.bin/truncate/truncate.c')
| -rw-r--r-- | usr.bin/truncate/truncate.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/usr.bin/truncate/truncate.c b/usr.bin/truncate/truncate.c new file mode 100644 index 0000000..12b81af --- /dev/null +++ b/usr.bin/truncate/truncate.c @@ -0,0 +1,160 @@ +/*- + * Copyright (c) 2000 Sheldon Hearn <sheldonh@FreeBSD.org>. + * 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. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 +static const char rcsid[] = + "$FreeBSD$"; +#endif + +#include <sys/stat.h> + +#include <ctype.h> +#include <err.h> +#include <errno.h> +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> + +#include <libutil.h> + +static void usage(void); + +static int no_create; +static int do_relative; +static int do_refer; +static int got_size; + +int +main(int argc, char **argv) +{ + struct stat sb; + mode_t omode; + off_t oflow, rsize, tsize; + int64_t sz; + int ch, error, fd, oflags; + char *fname, *rname; + + fd = -1; + rsize = tsize = sz = 0; + error = 0; + rname = NULL; + while ((ch = getopt(argc, argv, "cr:s:")) != -1) + switch (ch) { + case 'c': + no_create = 1; + break; + case 'r': + do_refer = 1; + rname = optarg; + break; + case 's': + if (expand_number(optarg, &sz) == -1) + errx(EXIT_FAILURE, + "invalid size argument `%s'", optarg); + if (*optarg == '+' || *optarg == '-') + do_relative = 1; + got_size = 1; + break; + default: + usage(); + /* NOTREACHED */ + } + + argv += optind; + argc -= optind; + + /* + * Exactly one of do_refer or got_size must be specified. Since + * do_relative implies got_size, do_relative and do_refer are + * also mutually exclusive. See usage() for allowed invocations. + */ + if (do_refer + got_size != 1 || argc < 1) + usage(); + if (do_refer) { + if (stat(rname, &sb) == -1) + err(EXIT_FAILURE, "%s", rname); + tsize = sb.st_size; + } else if (do_relative) + rsize = sz; + else + tsize = sz; + + if (no_create) + oflags = O_WRONLY; + else + oflags = O_WRONLY | O_CREAT; + omode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH; + + while ((fname = *argv++) != NULL) { + if (fd != -1) + close(fd); + if ((fd = open(fname, oflags, omode)) == -1) { + if (errno != ENOENT) { + warn("%s", fname); + error++; + } + continue; + } + if (do_relative) { + if (fstat(fd, &sb) == -1) { + warn("%s", fname); + error++; + continue; + } + oflow = sb.st_size + rsize; + if (oflow < (sb.st_size + rsize)) { + errno = EFBIG; + warn("%s", fname); + error++; + continue; + } + tsize = oflow; + } + if (tsize < 0) + tsize = 0; + + if (ftruncate(fd, tsize) == -1) { + warn("%s", fname); + error++; + continue; + } + } + if (fd != -1) + close(fd); + + return error ? EXIT_FAILURE : EXIT_SUCCESS; +} + +static void +usage(void) +{ + fprintf(stderr, "%s\n%s\n", + "usage: truncate [-c] -s [+|-]size[K|k|M|m|G|g|T|t] file ...", + " truncate [-c] -r rfile file ..."); + exit(EXIT_FAILURE); +} |
