d945888643
* src/common.h (set_file_atime): Add parentfd arg. * src/compare.c (diff_file): Use it. * src/create.c (dump_file0): Likewise. This closes yet another race condition with symbolic links. * src/misc.c (set_file_atime): Add parentfd arg.
957 lines
22 KiB
C
957 lines
22 KiB
C
/* Miscellaneous functions, not really specific to GNU tar.
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Copyright (C) 1988, 1992, 1994, 1995, 1996, 1997, 1999, 2000, 2001,
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2003, 2004, 2005, 2006, 2007, 2009, 2010 Free Software Foundation, Inc.
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This program is free software; you can redistribute it and/or modify it
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under the terms of the GNU General Public License as published by the
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Free Software Foundation; either version 3, or (at your option) any later
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version.
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This program is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
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Public License for more details.
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You should have received a copy of the GNU General Public License along
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with this program; if not, write to the Free Software Foundation, Inc.,
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51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
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#include <system.h>
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#include <rmt.h>
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#include "common.h"
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#include <quotearg.h>
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#include <save-cwd.h>
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#include <xgetcwd.h>
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#include <unlinkdir.h>
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#ifndef DOUBLE_SLASH_IS_DISTINCT_ROOT
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# define DOUBLE_SLASH_IS_DISTINCT_ROOT 0
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#endif
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/* Handling strings. */
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/* Assign STRING to a copy of VALUE if not zero, or to zero. If
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STRING was nonzero, it is freed first. */
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void
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assign_string (char **string, const char *value)
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{
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if (*string)
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free (*string);
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*string = value ? xstrdup (value) : 0;
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}
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#if 0
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/* This function is currently unused; perhaps it should be removed? */
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/* Allocate a copy of the string quoted as in C, and returns that. If
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the string does not have to be quoted, it returns a null pointer.
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The allocated copy should normally be freed with free() after the
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caller is done with it.
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This is used in one context only: generating the directory file in
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incremental dumps. The quoted string is not intended for human
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consumption; it is intended only for unquote_string. The quoting
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is locale-independent, so that users needn't worry about locale
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when reading directory files. This means that we can't use
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quotearg, as quotearg is locale-dependent and is meant for human
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consumption. */
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static char *
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quote_copy_string (const char *string)
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{
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const char *source = string;
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char *destination = 0;
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char *buffer = 0;
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int copying = 0;
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while (*source)
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{
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int character = *source++;
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switch (character)
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{
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case '\n': case '\\':
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if (!copying)
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{
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size_t length = (source - string) - 1;
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copying = 1;
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buffer = xmalloc (length + 2 + 2 * strlen (source) + 1);
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memcpy (buffer, string, length);
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destination = buffer + length;
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}
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*destination++ = '\\';
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*destination++ = character == '\\' ? '\\' : 'n';
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break;
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default:
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if (copying)
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*destination++ = character;
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break;
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}
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}
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if (copying)
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{
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*destination = '\0';
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return buffer;
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}
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return 0;
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}
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#endif
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/* Takes a quoted C string (like those produced by quote_copy_string)
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and turns it back into the un-quoted original. This is done in
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place. Returns 0 only if the string was not properly quoted, but
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completes the unquoting anyway.
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This is used for reading the saved directory file in incremental
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dumps. It is used for decoding old `N' records (demangling names).
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But also, it is used for decoding file arguments, would they come
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from the shell or a -T file, and for decoding the --exclude
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argument. */
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int
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unquote_string (char *string)
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{
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int result = 1;
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char *source = string;
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char *destination = string;
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/* Escape sequences other than \\ and \n are no longer generated by
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quote_copy_string, but accept them for backwards compatibility,
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and also because unquote_string is used for purposes other than
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parsing the output of quote_copy_string. */
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while (*source)
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if (*source == '\\')
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switch (*++source)
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{
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case '\\':
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*destination++ = '\\';
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source++;
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break;
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case 'a':
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*destination++ = '\a';
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source++;
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break;
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case 'b':
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*destination++ = '\b';
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source++;
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break;
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case 'f':
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*destination++ = '\f';
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source++;
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break;
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case 'n':
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*destination++ = '\n';
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source++;
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break;
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case 'r':
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*destination++ = '\r';
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source++;
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break;
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case 't':
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*destination++ = '\t';
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source++;
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break;
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case 'v':
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*destination++ = '\v';
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source++;
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break;
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case '?':
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*destination++ = 0177;
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source++;
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break;
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case '0':
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case '1':
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case '2':
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case '3':
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case '4':
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case '5':
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case '6':
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case '7':
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{
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int value = *source++ - '0';
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if (*source < '0' || *source > '7')
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{
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*destination++ = value;
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break;
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}
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value = value * 8 + *source++ - '0';
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if (*source < '0' || *source > '7')
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{
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*destination++ = value;
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break;
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}
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value = value * 8 + *source++ - '0';
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*destination++ = value;
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break;
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}
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default:
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result = 0;
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*destination++ = '\\';
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if (*source)
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*destination++ = *source++;
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break;
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}
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else if (source != destination)
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*destination++ = *source++;
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else
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source++, destination++;
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if (source != destination)
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*destination = '\0';
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return result;
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}
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/* Zap trailing slashes. */
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char *
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zap_slashes (char *name)
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{
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char *q;
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if (!name || *name == 0)
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return name;
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q = name + strlen (name) - 1;
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while (q > name && ISSLASH (*q))
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*q-- = '\0';
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return name;
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}
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/* Normalize FILE_NAME by removing redundant slashes and "."
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components, including redundant trailing slashes. Leave ".."
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alone, as it may be significant in the presence of symlinks and on
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platforms where "/.." != "/". Destructive version: modifies its
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argument. */
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static void
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normalize_filename_x (char *file_name)
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{
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char *name = file_name + FILE_SYSTEM_PREFIX_LEN (file_name);
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char *p;
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char const *q;
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char c;
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/* Don't squeeze leading "//" to "/", on hosts where they're distinct. */
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name += (DOUBLE_SLASH_IS_DISTINCT_ROOT
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&& ISSLASH (*name) && ISSLASH (name[1]) && ! ISSLASH (name[2]));
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/* Omit redundant leading "." components. */
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for (q = p = name; (*p = *q) == '.' && ISSLASH (q[1]); p += !*q)
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for (q += 2; ISSLASH (*q); q++)
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continue;
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/* Copy components from Q to P, omitting redundant slashes and
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internal "." components. */
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while ((*p++ = c = *q++) != '\0')
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if (ISSLASH (c))
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while (ISSLASH (q[*q == '.']))
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q += (*q == '.') + 1;
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/* Omit redundant trailing "." component and slash. */
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if (2 < p - name)
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{
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p -= p[-2] == '.' && ISSLASH (p[-3]);
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p -= 2 < p - name && ISSLASH (p[-2]);
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p[-1] = '\0';
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}
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}
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/* Normalize NAME by removing redundant slashes and "." components,
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including redundant trailing slashes. Return a normalized
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newly-allocated copy. */
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char *
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normalize_filename (const char *name)
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{
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char *copy = NULL;
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if (IS_RELATIVE_FILE_NAME (name))
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{
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/* Set COPY to the absolute file name if possible.
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FIXME: There should be no need to get the absolute file name.
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getcwd is slow, it might fail, and it does not necessarily
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return a canonical name even when it succeeds. Perhaps we
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can use dev+ino pairs instead of names? */
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copy = xgetcwd ();
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if (copy)
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{
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size_t copylen = strlen (copy);
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bool need_separator = ! (DOUBLE_SLASH_IS_DISTINCT_ROOT
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&& copylen == 2 && ISSLASH (copy[1]));
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copy = xrealloc (copy, copylen + need_separator + strlen (name) + 1);
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copy[copylen] = DIRECTORY_SEPARATOR;
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strcpy (copy + copylen + need_separator, name);
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}
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else
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WARN ((0, errno, _("Cannot get working directory")));
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}
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if (! copy)
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copy = xstrdup (name);
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normalize_filename_x (copy);
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return copy;
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}
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void
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replace_prefix (char **pname, const char *samp, size_t slen,
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const char *repl, size_t rlen)
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{
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char *name = *pname;
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size_t nlen = strlen (name);
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if (nlen > slen && memcmp (name, samp, slen) == 0 && ISSLASH (name[slen]))
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{
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if (rlen > slen)
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{
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name = xrealloc (name, nlen - slen + rlen + 1);
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*pname = name;
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}
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memmove (name + rlen, name + slen, nlen - slen + 1);
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memcpy (name, repl, rlen);
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}
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}
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/* Handling numbers. */
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/* Output fraction and trailing digits appropriate for a nanoseconds
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count equal to NS, but don't output unnecessary '.' or trailing
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zeros. */
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void
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code_ns_fraction (int ns, char *p)
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{
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if (ns == 0)
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*p = '\0';
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else
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{
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int i = 9;
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*p++ = '.';
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while (ns % 10 == 0)
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{
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ns /= 10;
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i--;
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}
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p[i] = '\0';
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for (;;)
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{
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p[--i] = '0' + ns % 10;
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if (i == 0)
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break;
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ns /= 10;
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}
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}
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}
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char const *
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code_timespec (struct timespec t, char sbuf[TIMESPEC_STRSIZE_BOUND])
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{
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time_t s = t.tv_sec;
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int ns = t.tv_nsec;
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char *np;
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bool negative = s < 0;
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/* ignore invalid values of ns */
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if (BILLION <= ns || ns < 0)
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ns = 0;
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if (negative && ns != 0)
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{
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s++;
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ns = BILLION - ns;
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}
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np = umaxtostr (negative ? - (uintmax_t) s : (uintmax_t) s, sbuf + 1);
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if (negative)
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*--np = '-';
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code_ns_fraction (ns, sbuf + UINTMAX_STRSIZE_BOUND);
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return np;
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}
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/* File handling. */
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/* Saved names in case backup needs to be undone. */
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static char *before_backup_name;
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static char *after_backup_name;
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/* Return 1 if FILE_NAME is obviously "." or "/". */
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static bool
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must_be_dot_or_slash (char const *file_name)
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{
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file_name += FILE_SYSTEM_PREFIX_LEN (file_name);
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if (ISSLASH (file_name[0]))
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{
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for (;;)
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if (ISSLASH (file_name[1]))
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file_name++;
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else if (file_name[1] == '.'
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&& ISSLASH (file_name[2 + (file_name[2] == '.')]))
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file_name += 2 + (file_name[2] == '.');
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else
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return ! file_name[1];
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}
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else
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{
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while (file_name[0] == '.' && ISSLASH (file_name[1]))
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{
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file_name += 2;
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while (ISSLASH (*file_name))
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file_name++;
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}
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return ! file_name[0] || (file_name[0] == '.' && ! file_name[1]);
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}
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}
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/* Some implementations of rmdir let you remove '.' or '/'.
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Report an error with errno set to zero for obvious cases of this;
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otherwise call rmdir. */
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static int
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safer_rmdir (const char *file_name)
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{
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if (must_be_dot_or_slash (file_name))
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{
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errno = 0;
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return -1;
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}
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return rmdir (file_name);
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}
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/* Remove FILE_NAME, returning 1 on success. If FILE_NAME is a directory,
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then if OPTION is RECURSIVE_REMOVE_OPTION is set remove FILE_NAME
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recursively; otherwise, remove it only if it is empty. If FILE_NAME is
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a directory that cannot be removed (e.g., because it is nonempty)
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and if OPTION is WANT_DIRECTORY_REMOVE_OPTION, then return -1.
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Return 0 on error, with errno set; if FILE_NAME is obviously the working
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directory return zero with errno set to zero. */
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int
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remove_any_file (const char *file_name, enum remove_option option)
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||
{
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/* Try unlink first if we cannot unlink directories, as this saves
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us a system call in the common case where we're removing a
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non-directory. */
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bool try_unlink_first = cannot_unlink_dir ();
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if (try_unlink_first)
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{
|
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if (unlink (file_name) == 0)
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return 1;
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|
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/* POSIX 1003.1-2001 requires EPERM when attempting to unlink a
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directory without appropriate privileges, but many Linux
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kernels return the more-sensible EISDIR. */
|
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if (errno != EPERM && errno != EISDIR)
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return 0;
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}
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|
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if (safer_rmdir (file_name) == 0)
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return 1;
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|
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switch (errno)
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{
|
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case ENOTDIR:
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return !try_unlink_first && unlink (file_name) == 0;
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|
||
case 0:
|
||
case EEXIST:
|
||
#if defined ENOTEMPTY && ENOTEMPTY != EEXIST
|
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case ENOTEMPTY:
|
||
#endif
|
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switch (option)
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{
|
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case ORDINARY_REMOVE_OPTION:
|
||
break;
|
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|
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case WANT_DIRECTORY_REMOVE_OPTION:
|
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return -1;
|
||
|
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case RECURSIVE_REMOVE_OPTION:
|
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{
|
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char *directory = savedir (file_name);
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char const *entry;
|
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size_t entrylen;
|
||
|
||
if (! directory)
|
||
return 0;
|
||
|
||
for (entry = directory;
|
||
(entrylen = strlen (entry)) != 0;
|
||
entry += entrylen + 1)
|
||
{
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||
char *file_name_buffer = new_name (file_name, entry);
|
||
int r = remove_any_file (file_name_buffer,
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RECURSIVE_REMOVE_OPTION);
|
||
int e = errno;
|
||
free (file_name_buffer);
|
||
|
||
if (! r)
|
||
{
|
||
free (directory);
|
||
errno = e;
|
||
return 0;
|
||
}
|
||
}
|
||
|
||
free (directory);
|
||
return safer_rmdir (file_name) == 0;
|
||
}
|
||
}
|
||
break;
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Check if FILE_NAME already exists and make a backup of it right now.
|
||
Return success (nonzero) only if the backup is either unneeded, or
|
||
successful. For now, directories are considered to never need
|
||
backup. If THIS_IS_THE_ARCHIVE is nonzero, this is the archive and
|
||
so, we do not have to backup block or character devices, nor remote
|
||
entities. */
|
||
bool
|
||
maybe_backup_file (const char *file_name, bool this_is_the_archive)
|
||
{
|
||
struct stat file_stat;
|
||
|
||
assign_string (&before_backup_name, file_name);
|
||
|
||
/* A run situation may exist between Emacs or other GNU programs trying to
|
||
make a backup for the same file simultaneously. If theoretically
|
||
possible, real problems are unlikely. Doing any better would require a
|
||
convention, GNU-wide, for all programs doing backups. */
|
||
|
||
assign_string (&after_backup_name, 0);
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||
|
||
/* Check if we really need to backup the file. */
|
||
|
||
if (this_is_the_archive && _remdev (file_name))
|
||
return true;
|
||
|
||
if (stat (file_name, &file_stat))
|
||
{
|
||
if (errno == ENOENT)
|
||
return true;
|
||
|
||
stat_error (file_name);
|
||
return false;
|
||
}
|
||
|
||
if (S_ISDIR (file_stat.st_mode))
|
||
return true;
|
||
|
||
if (this_is_the_archive
|
||
&& (S_ISBLK (file_stat.st_mode) || S_ISCHR (file_stat.st_mode)))
|
||
return true;
|
||
|
||
after_backup_name = find_backup_file_name (file_name, backup_type);
|
||
if (! after_backup_name)
|
||
xalloc_die ();
|
||
|
||
if (rename (before_backup_name, after_backup_name) == 0)
|
||
{
|
||
if (verbose_option)
|
||
fprintf (stdlis, _("Renaming %s to %s\n"),
|
||
quote_n (0, before_backup_name),
|
||
quote_n (1, after_backup_name));
|
||
return true;
|
||
}
|
||
else
|
||
{
|
||
/* The backup operation failed. */
|
||
int e = errno;
|
||
ERROR ((0, e, _("%s: Cannot rename to %s"),
|
||
quotearg_colon (before_backup_name),
|
||
quote_n (1, after_backup_name)));
|
||
assign_string (&after_backup_name, 0);
|
||
return false;
|
||
}
|
||
}
|
||
|
||
/* Try to restore the recently backed up file to its original name.
|
||
This is usually only needed after a failed extraction. */
|
||
void
|
||
undo_last_backup (void)
|
||
{
|
||
if (after_backup_name)
|
||
{
|
||
if (rename (after_backup_name, before_backup_name) != 0)
|
||
{
|
||
int e = errno;
|
||
ERROR ((0, e, _("%s: Cannot rename to %s"),
|
||
quotearg_colon (after_backup_name),
|
||
quote_n (1, before_backup_name)));
|
||
}
|
||
if (verbose_option)
|
||
fprintf (stdlis, _("Renaming %s back to %s\n"),
|
||
quote_n (0, after_backup_name),
|
||
quote_n (1, before_backup_name));
|
||
assign_string (&after_backup_name, 0);
|
||
}
|
||
}
|
||
|
||
/* Depending on DEREF, apply either stat or lstat to (NAME, BUF). */
|
||
int
|
||
deref_stat (bool deref, char const *name, struct stat *buf)
|
||
{
|
||
return deref ? stat (name, buf) : lstat (name, buf);
|
||
}
|
||
|
||
/* Use futimens if possible, utimensat otherwise. */
|
||
int
|
||
fd_utimensat (int fd, int parentfd, char const *file,
|
||
struct timespec const ts[2], int atflag)
|
||
{
|
||
if (0 <= fd)
|
||
{
|
||
int result = futimens (fd, ts);
|
||
if (! (result < 0 && errno == ENOSYS))
|
||
return result;
|
||
}
|
||
|
||
return utimensat (parentfd, file, ts, atflag);
|
||
}
|
||
|
||
/* Set FD's (i.e., assuming the working directory is PARENTFD, FILE's)
|
||
access time to ATIME. ATFLAG controls symbolic-link following, in
|
||
the style of openat. */
|
||
int
|
||
set_file_atime (int fd, int parentfd, char const *file, struct timespec atime,
|
||
int atflag)
|
||
{
|
||
struct timespec ts[2];
|
||
ts[0] = atime;
|
||
ts[1].tv_nsec = UTIME_OMIT;
|
||
return fd_utimensat (fd, parentfd, file, ts, atflag);
|
||
}
|
||
|
||
/* A description of a working directory. */
|
||
struct wd
|
||
{
|
||
/* The directory's name. */
|
||
char const *name;
|
||
|
||
/* A negative value if no attempt has been made to save the
|
||
directory, 0 if it was saved successfully, and a positive errno
|
||
value if it was not saved successfully. */
|
||
int err;
|
||
|
||
/* The saved version of the directory, if ERR == 0. */
|
||
struct saved_cwd saved_cwd;
|
||
};
|
||
|
||
/* A vector of chdir targets. wd[0] is the initial working directory. */
|
||
static struct wd *wd;
|
||
|
||
/* The number of working directories in the vector. */
|
||
static size_t wd_count;
|
||
|
||
/* The allocated size of the vector. */
|
||
static size_t wd_alloc;
|
||
|
||
int
|
||
chdir_count ()
|
||
{
|
||
if (wd_count == 0)
|
||
return wd_count;
|
||
return wd_count - 1;
|
||
}
|
||
|
||
/* DIR is the operand of a -C option; add it to vector of chdir targets,
|
||
and return the index of its location. */
|
||
int
|
||
chdir_arg (char const *dir)
|
||
{
|
||
if (wd_count == wd_alloc)
|
||
{
|
||
if (wd_alloc == 0)
|
||
{
|
||
wd_alloc = 2;
|
||
wd = xmalloc (sizeof *wd * wd_alloc);
|
||
}
|
||
else
|
||
wd = x2nrealloc (wd, &wd_alloc, sizeof *wd);
|
||
|
||
if (! wd_count)
|
||
{
|
||
wd[wd_count].name = ".";
|
||
wd[wd_count].err = -1;
|
||
wd_count++;
|
||
}
|
||
}
|
||
|
||
/* Optimize the common special case of the working directory,
|
||
or the working directory as a prefix. */
|
||
if (dir[0])
|
||
{
|
||
while (dir[0] == '.' && ISSLASH (dir[1]))
|
||
for (dir += 2; ISSLASH (*dir); dir++)
|
||
continue;
|
||
if (! dir[dir[0] == '.'])
|
||
return wd_count - 1;
|
||
}
|
||
|
||
wd[wd_count].name = dir;
|
||
wd[wd_count].err = -1;
|
||
return wd_count++;
|
||
}
|
||
|
||
/* Index of current directory. */
|
||
int chdir_current;
|
||
|
||
/* Change to directory I. If I is 0, change to the initial working
|
||
directory; otherwise, I must be a value returned by chdir_arg. */
|
||
void
|
||
chdir_do (int i)
|
||
{
|
||
if (chdir_current != i)
|
||
{
|
||
struct wd *prev = &wd[chdir_current];
|
||
struct wd *curr = &wd[i];
|
||
|
||
if (prev->err < 0)
|
||
{
|
||
prev->err = 0;
|
||
if (save_cwd (&prev->saved_cwd) != 0)
|
||
prev->err = errno;
|
||
else if (0 <= prev->saved_cwd.desc)
|
||
{
|
||
/* Make sure we still have at least one descriptor available. */
|
||
int fd1 = prev->saved_cwd.desc;
|
||
int fd2 = dup (fd1);
|
||
if (0 <= fd2)
|
||
close (fd2);
|
||
else if (errno == EMFILE)
|
||
{
|
||
/* Force restore_cwd to use chdir_long. */
|
||
close (fd1);
|
||
prev->saved_cwd.desc = -1;
|
||
prev->saved_cwd.name = xgetcwd ();
|
||
if (! prev->saved_cwd.name)
|
||
prev->err = errno;
|
||
}
|
||
else
|
||
prev->err = errno;
|
||
}
|
||
}
|
||
|
||
if (0 <= curr->err)
|
||
{
|
||
int err = curr->err;
|
||
if (err == 0 && restore_cwd (&curr->saved_cwd) != 0)
|
||
err = errno;
|
||
if (err)
|
||
FATAL_ERROR ((0, err, _("Cannot restore working directory")));
|
||
}
|
||
else
|
||
{
|
||
if (i && ! ISSLASH (curr->name[0]))
|
||
chdir_do (i - 1);
|
||
if (chdir (curr->name) != 0)
|
||
chdir_fatal (curr->name);
|
||
}
|
||
|
||
chdir_current = i;
|
||
}
|
||
}
|
||
|
||
void
|
||
close_diag (char const *name)
|
||
{
|
||
if (ignore_failed_read_option)
|
||
close_warn (name);
|
||
else
|
||
close_error (name);
|
||
}
|
||
|
||
void
|
||
open_diag (char const *name)
|
||
{
|
||
if (ignore_failed_read_option)
|
||
open_warn (name);
|
||
else
|
||
open_error (name);
|
||
}
|
||
|
||
void
|
||
read_diag_details (char const *name, off_t offset, size_t size)
|
||
{
|
||
if (ignore_failed_read_option)
|
||
read_warn_details (name, offset, size);
|
||
else
|
||
read_error_details (name, offset, size);
|
||
}
|
||
|
||
void
|
||
readlink_diag (char const *name)
|
||
{
|
||
if (ignore_failed_read_option)
|
||
readlink_warn (name);
|
||
else
|
||
readlink_error (name);
|
||
}
|
||
|
||
void
|
||
savedir_diag (char const *name)
|
||
{
|
||
if (ignore_failed_read_option)
|
||
savedir_warn (name);
|
||
else
|
||
savedir_error (name);
|
||
}
|
||
|
||
void
|
||
seek_diag_details (char const *name, off_t offset)
|
||
{
|
||
if (ignore_failed_read_option)
|
||
seek_warn_details (name, offset);
|
||
else
|
||
seek_error_details (name, offset);
|
||
}
|
||
|
||
void
|
||
stat_diag (char const *name)
|
||
{
|
||
if (ignore_failed_read_option)
|
||
stat_warn (name);
|
||
else
|
||
stat_error (name);
|
||
}
|
||
|
||
void
|
||
file_removed_diag (const char *name, bool top_level,
|
||
void (*diagfn) (char const *name))
|
||
{
|
||
if (!top_level && errno == ENOENT)
|
||
{
|
||
WARNOPT (WARN_FILE_REMOVED,
|
||
(0, 0, _("%s: File removed before we read it"),
|
||
quotearg_colon (name)));
|
||
set_exit_status (TAREXIT_DIFFERS);
|
||
}
|
||
else
|
||
diagfn (name);
|
||
}
|
||
|
||
void
|
||
dir_removed_diag (const char *name, bool top_level,
|
||
void (*diagfn) (char const *name))
|
||
{
|
||
if (!top_level && errno == ENOENT)
|
||
{
|
||
WARNOPT (WARN_FILE_REMOVED,
|
||
(0, 0, _("%s: Directory removed before we read it"),
|
||
quotearg_colon (name)));
|
||
set_exit_status (TAREXIT_DIFFERS);
|
||
}
|
||
else
|
||
diagfn (name);
|
||
}
|
||
|
||
void
|
||
write_fatal_details (char const *name, ssize_t status, size_t size)
|
||
{
|
||
write_error_details (name, status, size);
|
||
fatal_exit ();
|
||
}
|
||
|
||
/* Fork, aborting if unsuccessful. */
|
||
pid_t
|
||
xfork (void)
|
||
{
|
||
pid_t p = fork ();
|
||
if (p == (pid_t) -1)
|
||
call_arg_fatal ("fork", _("child process"));
|
||
return p;
|
||
}
|
||
|
||
/* Create a pipe, aborting if unsuccessful. */
|
||
void
|
||
xpipe (int fd[2])
|
||
{
|
||
if (pipe (fd) < 0)
|
||
call_arg_fatal ("pipe", _("interprocess channel"));
|
||
}
|
||
|
||
/* Return PTR, aligned upward to the next multiple of ALIGNMENT.
|
||
ALIGNMENT must be nonzero. The caller must arrange for ((char *)
|
||
PTR) through ((char *) PTR + ALIGNMENT - 1) to be addressable
|
||
locations. */
|
||
|
||
static inline void *
|
||
ptr_align (void *ptr, size_t alignment)
|
||
{
|
||
char *p0 = ptr;
|
||
char *p1 = p0 + alignment - 1;
|
||
return p1 - (size_t) p1 % alignment;
|
||
}
|
||
|
||
/* Return the address of a page-aligned buffer of at least SIZE bytes.
|
||
The caller should free *PTR when done with the buffer. */
|
||
|
||
void *
|
||
page_aligned_alloc (void **ptr, size_t size)
|
||
{
|
||
size_t alignment = getpagesize ();
|
||
size_t size1 = size + alignment;
|
||
if (size1 < size)
|
||
xalloc_die ();
|
||
*ptr = xmalloc (size1);
|
||
return ptr_align (*ptr, alignment);
|
||
}
|
||
|
||
|
||
|
||
struct namebuf
|
||
{
|
||
char *buffer; /* directory, `/', and directory member */
|
||
size_t buffer_size; /* allocated size of name_buffer */
|
||
size_t dir_length; /* length of directory part in buffer */
|
||
};
|
||
|
||
namebuf_t
|
||
namebuf_create (const char *dir)
|
||
{
|
||
namebuf_t buf = xmalloc (sizeof (*buf));
|
||
buf->buffer_size = strlen (dir) + 2;
|
||
buf->buffer = xmalloc (buf->buffer_size);
|
||
strcpy (buf->buffer, dir);
|
||
buf->dir_length = strlen (buf->buffer);
|
||
if (!ISSLASH (buf->buffer[buf->dir_length - 1]))
|
||
buf->buffer[buf->dir_length++] = DIRECTORY_SEPARATOR;
|
||
return buf;
|
||
}
|
||
|
||
void
|
||
namebuf_free (namebuf_t buf)
|
||
{
|
||
free (buf->buffer);
|
||
free (buf);
|
||
}
|
||
|
||
char *
|
||
namebuf_name (namebuf_t buf, const char *name)
|
||
{
|
||
size_t len = strlen (name);
|
||
while (buf->dir_length + len + 1 >= buf->buffer_size)
|
||
buf->buffer = x2realloc (buf->buffer, &buf->buffer_size);
|
||
strcpy (buf->buffer + buf->dir_length, name);
|
||
return buf->buffer;
|
||
}
|