qubes-installer-qubes-os/anaconda/pyanaconda/isys/imount.c
2013-01-24 01:45:53 +01:00

258 lines
7.2 KiB
C

/*
* imount.c
*
* Copyright (C) 2007, 2008, 2009 Red Hat, Inc. All rights reserved.
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <glib.h>
#include "imount.h"
#include "log.h"
#define _(foo) foo
static int readFD(int fd, char **buf) {
char *p;
size_t size = 4096;
int s, filesize = 0;
*buf = calloc(4096, sizeof (char));
if (*buf == NULL)
abort();
do {
p = &(*buf)[filesize];
s = read(fd, p, 4096);
if (s < 0)
break;
filesize += s;
if (s == 0)
break;
size += s;
*buf = realloc(*buf, size);
if (*buf == NULL)
abort();
} while (1);
if (filesize == 0 && s < 0) {
free(*buf);
*buf = NULL;
return -1;
}
return filesize;
}
static size_t rstrip(char *str) {
size_t len = strlen(str);
if (len > 0 && str[len-1] == '\n') {
str[len-1] = '\0';
--len;
}
return len;
}
int mountCommandWrapper(int mode, char *dev, char *where, char *fs,
char *options, char **err) {
int rc, child, status;
int stdout_pipe[2], stderr_pipe[2];
char *opts = NULL, *device = NULL, *cmd = NULL;
switch (mode) {
case IMOUNT_MODE_MOUNT:
case IMOUNT_MODE_BIND:
cmd = "/bin/mount";
if (g_mkdir_with_parents(where, 0755))
return IMOUNT_ERR_ERRNO;
break;
case IMOUNT_MODE_UMOUNT:
cmd = "/bin/umount";
break;
default:
return IMOUNT_ERR_MODE;
}
if (mode == IMOUNT_MODE_MOUNT) {
if (strstr(fs, "nfs")) {
if (options && strlen(options)) { // do not append if the options are empty
if (asprintf(&opts, "%s,nolock", options) == -1) {
fprintf(stderr, "%s: %d: %s\n", __func__, __LINE__,
strerror(errno));
fflush(stderr);
abort();
}
} else {
opts = strdup("nolock");
}
device = strdup(dev);
} else {
if ((options && strstr(options, "bind") == NULL) &&
strncmp(dev, "LABEL=", 6) && strncmp(dev, "UUID=", 5) &&
*dev != '/') {
if (asprintf(&device, "/dev/%s", dev) == -1) {
fprintf(stderr, "%s: %d: %s\n", __func__, __LINE__,
strerror(errno));
fflush(stderr);
abort();
}
} else {
device = strdup(dev);
}
if (options)
opts = strdup(options);
}
}
if (pipe(stdout_pipe))
return IMOUNT_ERR_ERRNO;
if (pipe(stderr_pipe))
return IMOUNT_ERR_ERRNO;
if (!(child = fork())) {
int tty_fd;
close(stdout_pipe[0]);
close(stderr_pipe[0]);
/* Pull stdin from /dev/tty5 and redirect stdout and stderr to the pipes
* so we can log the output and put error messages into exceptions.
* We'll only use these messages should mount also return an error
* code.
*/
tty_fd = open("/dev/tty5", O_RDONLY);
close(STDIN_FILENO);
dup2(tty_fd, STDIN_FILENO);
close(tty_fd);
close(STDOUT_FILENO);
dup2(stdout_pipe[1], STDOUT_FILENO);
close(STDERR_FILENO);
dup2(stderr_pipe[1], STDERR_FILENO);
if (mode == IMOUNT_MODE_MOUNT) {
if (opts) {
logProgramMessage(INFO, "Running... %s -n -t %s -o %s %s %s",
cmd, fs, opts, device, where);
rc = execl(cmd, cmd,
"-n", "-t", fs, "-o", opts, device, where, NULL);
exit(1);
} else {
logProgramMessage(INFO, "Running... %s -n -t %s %s %s",
cmd, fs, device, where);
rc = execl(cmd, cmd, "-n", "-t", fs, device, where, NULL);
exit(1);
}
} else if (mode == IMOUNT_MODE_BIND) {
logProgramMessage(INFO, "Running... %s --bind %s %s",
cmd, dev, where);
rc = execl(cmd, cmd, "--bind", dev, where, NULL);
exit(1);
} else if (mode == IMOUNT_MODE_UMOUNT) {
logProgramMessage(INFO, "Running... %s %s", cmd, where);
rc = execl(cmd, cmd, where, NULL);
exit(1);
} else {
logProgramMessage(ERROR, "Running... Unknown imount mode: %d\n", mode);
exit(1);
}
}
close(stdout_pipe[1]);
close(stderr_pipe[1]);
char *buffer = NULL;
/* In case when when the stderr pipe gets enough data to fill the kernel
* buffer we might see a deadlock as this will block the mount program on
* its next write(). The buffer size is 65kB though so we should be safe.
*/
rc = readFD(stdout_pipe[0], &buffer);
if (rc > 0) {
rstrip(buffer);
logProgramMessage(INFO, buffer);
free(buffer);
buffer = NULL;
}
rc = readFD(stderr_pipe[0], &buffer);
if (rc > 0) {
rstrip(buffer);
logProgramMessage(ERROR, buffer);
if (err != NULL)
*err = buffer;
else
free(buffer);
}
waitpid(child, &status, 0);
close(stdout_pipe[0]);
close(stderr_pipe[0]);
if (opts) {
free(opts);
}
if (device) {
free(device);
}
if (!WIFEXITED(status))
return IMOUNT_ERR_OTHER;
else if ( (rc = WEXITSTATUS(status)) )
return rc;
return 0;
}
int doBindMount(char* path, char *where, char **err) {
return mountCommandWrapper(IMOUNT_MODE_BIND,
path, where, NULL, NULL, err);
}
int doPwMount(char *dev, char *where, char *fs, char *options, char **err) {
return mountCommandWrapper(IMOUNT_MODE_MOUNT,
dev, where, fs, options, err);
}
int doPwUmount(char *where, char **err) {
return mountCommandWrapper(IMOUNT_MODE_UMOUNT,
NULL, where, NULL, NULL, err);
}
/* Returns true iff it is possible that the mount command that have returned
* 'errno' might succeed at a later time (think e.g. not yet initialized USB
* device, etc.) */
int mountMightSucceedLater(int mountRc)
{
/* 32 is the mount exit code for "mount failure" */
if (mountRc > 0 && mountRc & 0x20)
return 1;
else
return 0;
}