/* truncate -- truncate or extend the length of files.
- Copyright (C) 2008-2009 Free Software Foundation, Inc.
+ Copyright (C) 2008-2013 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
This is backwards compatible with the FreeBSD utility, but is more
flexible wrt the size specifications and the use of long options,
- to better fit the "GNU" environment.
-
- Note if !defined(HAVE_FTRUNCATE) then the --skip-ftruncate configure flag
- was specified or we're in a mingw environment. In these cases gnulib
- emulation will be used and GNULIB_FTRUNCATE is defined. Note if emulation
- can't even be provided ftruncate() will return EIO. */
+ to better fit the "GNU" environment. */
#include <config.h> /* sets _FILE_OFFSET_BITS=64 etc. */
#include <stdio.h>
#include "system.h"
#include "error.h"
-#include "posixver.h"
#include "quote.h"
+#include "stat-size.h"
#include "xstrtol.h"
-/* The official name of this program (e.g., no `g' prefix). */
+/* The official name of this program (e.g., no 'g' prefix). */
#define PROGRAM_NAME "truncate"
#define AUTHORS proper_name_utf8 ("Padraig Brady", "P\303\241draig Brady")
usage (int status)
{
if (status != EXIT_SUCCESS)
- fprintf (stderr, _("Try `%s --help' for more information.\n"),
- program_name);
+ emit_try_help ();
else
{
printf (_("Usage: %s OPTION... FILE...\n"), program_name);
-c, --no-create do not create any files\n\
"), stdout);
fputs (_("\
- -o, --io-blocks Treat SIZE as number of IO blocks instead of bytes\n\
+ -o, --io-blocks treat SIZE as number of IO blocks instead of bytes\n\
"), stdout);
fputs (_("\
- -r, --reference=FILE use this FILE's size\n\
- -s, --size=SIZE use this SIZE\n"), stdout);
+ -r, --reference=RFILE base size on RFILE\n\
+ -s, --size=SIZE set or adjust the file size by SIZE\n"), stdout);
fputs (HELP_OPTION_DESCRIPTION, stdout);
fputs (VERSION_OPTION_DESCRIPTION, stdout);
emit_size_note ();
fputs (_("\n\
SIZE may also be prefixed by one of the following modifying characters:\n\
-`+' extend by, `-' reduce by, `<' at most, `>' at least,\n\
-`/' round down to multiple of, `%' round up to multiple of.\n"), stdout);
- fputs (_("\
-\n\
-Note that the -r and -s options are mutually exclusive.\n\
-"), stdout);
+'+' extend by, '-' reduce by, '<' at most, '>' at least,\n\
+'/' round down to multiple of, '%' round up to multiple of.\n"), stdout);
emit_ancillary_info ();
}
exit (status);
}
-/* return 1 on error, 0 on success */
-static int
-do_ftruncate (int fd, char const *fname, off_t ssize, rel_mode_t rel_mode)
+/* return true on success, false on error. */
+static bool
+do_ftruncate (int fd, char const *fname, off_t ssize, off_t rsize,
+ rel_mode_t rel_mode)
{
struct stat sb;
off_t nsize;
- if ((block_mode || rel_mode) && fstat (fd, &sb) != 0)
+ if ((block_mode || (rel_mode && rsize < 0)) && fstat (fd, &sb) != 0)
{
error (0, errno, _("cannot fstat %s"), quote (fname));
- return 1;
+ return false;
}
if (block_mode)
{
" * %" PRIdMAX " byte blocks for file %s"),
(intmax_t) ssize, (intmax_t) blksize,
quote (fname));
- return 1;
+ return false;
}
ssize *= blksize;
}
if (rel_mode)
{
- uintmax_t const fsize = sb.st_size;
+ uintmax_t fsize;
- if (sb.st_size < 0)
+ if (0 <= rsize)
+ fsize = rsize;
+ else
{
- /* Complain only for a regular file, a directory,
- or a shared memory object, as POSIX 1003.1-2004 specifies
- ftruncate's behavior only for these file types. */
- if (S_ISREG (sb.st_mode) || S_ISDIR (sb.st_mode)
- || S_TYPEISSHM (&sb))
+ off_t file_size;
+ if (usable_st_size (&sb))
{
- /* overflow is the only reason I can think
- this would ever go negative for the above types */
- error (0, 0, _("%s has unusable, apparently negative size"),
- quote (fname));
- return 1;
+ file_size = sb.st_size;
+ if (file_size < 0)
+ {
+ /* Sanity check. Overflow is the only reason I can think
+ this would ever go negative. */
+ error (0, 0, _("%s has unusable, apparently negative size"),
+ quote (fname));
+ return false;
+ }
+ }
+ else
+ {
+ file_size = lseek (fd, 0, SEEK_END);
+ if (file_size < 0)
+ {
+ error (0, errno, _("cannot get the size of %s"),
+ quote (fname));
+ return false;
+ }
}
- return 0;
+ fsize = file_size;
}
if (rel_mode == rm_min)
{
error (0, 0, _("overflow rounding up size of file %s"),
quote (fname));
- return 1;
+ return false;
}
nsize = overflow;
}
{
error (0, 0, _("overflow extending size of file %s"),
quote (fname));
- return 1;
+ return false;
}
nsize = fsize + ssize;
}
if (ftruncate (fd, nsize) == -1) /* note updates mtime & ctime */
{
- /* Complain only when ftruncate fails on a regular file, a
- directory, or a shared memory object, as POSIX 1003.1-2004
- specifies ftruncate's behavior only for these file types.
- For example, do not complain when Linux kernel 2.4 ftruncate
- fails on /dev/fd0. */
- int const ftruncate_errno = errno;
- if (fstat (fd, &sb) != 0)
- {
- error (0, errno, _("cannot fstat %s"), quote (fname));
- return 1;
- }
- else if (S_ISREG (sb.st_mode) || S_ISDIR (sb.st_mode)
- || S_TYPEISSHM (&sb))
- {
- error (0, ftruncate_errno,
- _("truncating %s at %" PRIdMAX " bytes"), quote (fname),
- (intmax_t) nsize);
- return 1;
- }
- return 0;
+ error (0, errno,
+ _("failed to truncate %s at %" PRIdMAX " bytes"), quote (fname),
+ (intmax_t) nsize);
+ return false;
}
- return 0;
+ return true;
}
int
main (int argc, char **argv)
{
bool got_size = false;
- off_t size IF_LINT (= 0);
+ bool errors = false;
+ off_t size IF_LINT ( = 0);
+ off_t rsize = -1;
rel_mode_t rel_mode = rm_abs;
- mode_t omode;
- int c, errors = 0, fd = -1, oflags;
+ int c, fd = -1, oflags;
char const *fname;
initialize_main (&argc, &argv);
argc -= optind;
/* must specify either size or reference file */
- if ((ref_file && got_size) || (!ref_file && !got_size))
+ if (!ref_file && !got_size)
+ {
+ error (0, 0, _("you must specify either %s or %s"),
+ quote_n (0, "--size"), quote_n (1, "--reference"));
+ usage (EXIT_FAILURE);
+ }
+ /* must specify a relative size with a reference file */
+ if (ref_file && got_size && !rel_mode)
{
- error (0, 0, _("you must specify one of %s or %s"),
+ error (0, 0, _("you must specify a relative %s with %s"),
quote_n (0, "--size"), quote_n (1, "--reference"));
usage (EXIT_FAILURE);
}
if (ref_file)
{
struct stat sb;
+ off_t file_size = -1;
if (stat (ref_file, &sb) != 0)
error (EXIT_FAILURE, errno, _("cannot stat %s"), quote (ref_file));
- size = sb.st_size;
+ if (usable_st_size (&sb))
+ file_size = sb.st_size;
+ else
+ {
+ int ref_fd = open (ref_file, O_RDONLY);
+ if (0 <= ref_fd)
+ {
+ off_t file_end = lseek (ref_fd, 0, SEEK_END);
+ int saved_errno = errno;
+ close (ref_fd); /* ignore failure */
+ if (0 <= file_end)
+ file_size = file_end;
+ else
+ {
+ /* restore, in case close clobbered it. */
+ errno = saved_errno;
+ }
+ }
+ }
+ if (file_size < 0)
+ error (EXIT_FAILURE, errno, _("cannot get the size of %s"),
+ quote (ref_file));
+ if (!got_size)
+ size = file_size;
+ else
+ rsize = file_size;
}
oflags = O_WRONLY | (no_create ? 0 : O_CREAT) | O_NONBLOCK;
- omode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH;
while ((fname = *argv++) != NULL)
{
- if ((fd = open (fname, oflags, omode)) == -1)
+ if ((fd = open (fname, oflags, MODE_RW_UGO)) == -1)
{
- /* `truncate -s0 -c no-such-file` shouldn't gen error
- `truncate -s0 no-such-dir/file` should gen ENOENT error
- `truncate -s0 no-such-dir/` should gen EISDIR error
- `truncate -s0 .` should gen EISDIR error */
+ /* 'truncate -s0 -c no-such-file' shouldn't gen error
+ 'truncate -s0 no-such-dir/file' should gen ENOENT error
+ 'truncate -s0 no-such-dir/' should gen EISDIR error
+ 'truncate -s0 .' should gen EISDIR error */
if (!(no_create && errno == ENOENT))
{
- int const open_errno = errno;
- struct stat sb;
- if (stat (fname, &sb) == 0)
- {
- /* Complain only for a regular file, a directory,
- or a shared memory object, as POSIX 1003.1-2004 specifies
- ftruncate's behavior only for these file types. */
- if (!S_ISREG (sb.st_mode) && !S_ISDIR (sb.st_mode)
- && !S_TYPEISSHM (&sb))
- continue;
- }
- error (0, open_errno, _("cannot open %s for writing"),
+ error (0, errno, _("cannot open %s for writing"),
quote (fname));
- errors++;
+ errors = true;
}
continue;
}
if (fd != -1)
{
- errors += do_ftruncate (fd, fname, size, rel_mode);
+ errors |= !do_ftruncate (fd, fname, size, rsize, rel_mode);
if (close (fd) != 0)
{
error (0, errno, _("closing %s"), quote (fname));
- errors++;
+ errors = true;
}
}
}
projects / platform / upstream / coreutils.git / blobdiff