freebsd-dev/gnu/usr.bin/grep/savedir.c

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/* savedir.c -- save the list of files in a directory in a string
Copyright (C) 1990, 1997, 1998, 1999, 2000 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
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program 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 this program; if not, write to the Free Software Foundation,
Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
/* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */
#if HAVE_CONFIG_H
# include <config.h>
#endif
#include <sys/types.h>
#if HAVE_UNISTD_H
# include <unistd.h>
#endif
#if HAVE_DIRENT_H
# include <dirent.h>
# define NAMLEN(dirent) strlen((dirent)->d_name)
#else
# define dirent direct
# define NAMLEN(dirent) (dirent)->d_namlen
# if HAVE_SYS_NDIR_H
# include <sys/ndir.h>
# endif
# if HAVE_SYS_DIR_H
# include <sys/dir.h>
# endif
# if HAVE_NDIR_H
# include <ndir.h>
# endif
#endif
#ifdef CLOSEDIR_VOID
/* Fake a return value. */
# define CLOSEDIR(d) (closedir (d), 0)
#else
# define CLOSEDIR(d) closedir (d)
#endif
#ifdef STDC_HEADERS
# include <stdlib.h>
# include <string.h>
#else
char *malloc ();
char *realloc ();
#endif
#ifndef NULL
# define NULL 0
#endif
#ifndef stpcpy
char *stpcpy ();
#endif
#include "savedir.h"
/* Return a freshly allocated string containing the filenames
in directory DIR, separated by '\0' characters;
the end is marked by two '\0' characters in a row.
NAME_SIZE is the number of bytes to initially allocate
for the string; it will be enlarged as needed.
Return NULL if DIR cannot be opened or if out of memory. */
char *
savedir (const char *dir, off_t name_size)
{
DIR *dirp;
struct dirent *dp;
char *name_space;
char *namep;
dirp = opendir (dir);
if (dirp == NULL)
return NULL;
/* Be sure name_size is at least `1' so there's room for
the final NUL byte. */
name_size += !name_size;
name_space = (char *) malloc (name_size);
if (name_space == NULL)
{
closedir (dirp);
return NULL;
}
namep = name_space;
while ((dp = readdir (dirp)) != NULL)
{
/* Skip "." and ".." (some NFS filesystems' directories lack them). */
if (dp->d_name[0] != '.'
|| (dp->d_name[1] != '\0'
&& (dp->d_name[1] != '.' || dp->d_name[2] != '\0')))
{
off_t size_needed = (namep - name_space) + NAMLEN (dp) + 2;
if (size_needed > name_size)
{
char *new_name_space;
while (size_needed > name_size)
name_size += 1024;
new_name_space = realloc (name_space, name_size);
if (new_name_space == NULL)
{
closedir (dirp);
return NULL;
}
namep += new_name_space - name_space;
name_space = new_name_space;
}
namep = stpcpy (namep, dp->d_name) + 1;
}
}
*namep = '\0';
if (CLOSEDIR (dirp))
{
free (name_space);
return NULL;
}
return name_space;
}