Files
libguestfs/daemon/grep.c
Richard W.M. Jones 606732d02e Use O_CLOEXEC / SOCK_CLOEXEC for almost all file descriptors.
The presumption is that all file descriptors should be created with
the close-on-exec flag set.  The only exception are file descriptors
that we want passed through to exec'd subprocesses (mainly pipes and
stdin/stdout/stderr).

For open calls, we pass O_CLOEXEC as an extra flag, eg:

  fd = open ("foo", O_RDONLY|O_CLOEXEC);

This is a Linux-ism, but using a macro we can easily make it portable.

For sockets, similarly:

  sock = socket (..., SOCK_STREAM|SOCK_CLOEXEC, ...);

For accepted sockets, we use the Linux accept4 system call which
allows flags to be supplied, but we use the Gnulib 'accept4' module to
make this portable.

For dup, dup2, we use the Linux dup3 system call, and the Gnulib
modules 'dup3' and 'cloexec'.
2012-03-14 19:30:46 +00:00

140 lines
3.0 KiB
C

/* libguestfs - the guestfsd daemon
* Copyright (C) 2009 Red Hat 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 of the License, 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include "guestfs_protocol.h"
#include "daemon.h"
#include "actions.h"
static char **
grep (const char *prog, const char *flag, const char *regex, const char *path)
{
char *out, *err;
int fd, flags, r;
char **lines;
CHROOT_IN;
fd = open (path, O_RDONLY|O_CLOEXEC);
CHROOT_OUT;
if (fd == -1) {
reply_with_perror ("%s", path);
return NULL;
}
/* Note that grep returns an error if no match. We want to
* suppress this error and return an empty list.
*/
flags = COMMAND_FLAG_CHROOT_COPY_FILE_TO_STDIN | fd;
r = commandrf (&out, &err, flags, prog, flag, regex, NULL);
if (r == -1 || r > 1) {
reply_with_error ("%s %s %s: %s", prog, flag, regex, err);
free (out);
free (err);
return NULL;
}
free (err);
lines = split_lines (out);
free (out);
if (lines == NULL) return NULL;
return lines;
}
char **
do_grep (const char *regex, const char *path)
{
/* The "--" is not really needed, but it helps when we don't need a flag. */
return grep ("grep", "--", regex, path);
}
char **
do_egrep (const char *regex, const char *path)
{
return grep ("egrep", "--", regex, path);
}
char **
do_fgrep (const char *regex, const char *path)
{
return grep ("fgrep", "--", regex, path);
}
char **
do_grepi (const char *regex, const char *path)
{
return grep ("grep", "-i", regex, path);
}
char **
do_egrepi (const char *regex, const char *path)
{
return grep ("egrep", "-i", regex, path);
}
char **
do_fgrepi (const char *regex, const char *path)
{
return grep ("fgrep", "-i", regex, path);
}
char **
do_zgrep (const char *regex, const char *path)
{
return grep ("zgrep", "--", regex, path);
}
char **
do_zegrep (const char *regex, const char *path)
{
return grep ("zegrep", "--", regex, path);
}
char **
do_zfgrep (const char *regex, const char *path)
{
return grep ("zfgrep", "--", regex, path);
}
char **
do_zgrepi (const char *regex, const char *path)
{
return grep ("zgrep", "-i", regex, path);
}
char **
do_zegrepi (const char *regex, const char *path)
{
return grep ("zegrep", "-i", regex, path);
}
char **
do_zfgrepi (const char *regex, const char *path)
{
return grep ("zfgrep", "-i", regex, path);
}