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#include "internal.h"
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <mntent.h>
#include <sys/mount.h>
extern const char mtab_file[]; /* Defined in utility.c */
static char *
stralloc(const char * string)
{
int length = strlen(string) + 1;
char * n = malloc(length);
memcpy(n, string, length);
return n;
}
extern void
erase_mtab(const char * name)
{
struct mntent entries[20];
int count = 0;
FILE *mountTable = setmntent(mtab_file, "r");
struct mntent * m;
if ( mountTable == 0
&& (mountTable = setmntent("/proc/mounts", "r")) == 0 ) {
perror(mtab_file);
return;
}
while ( (m = getmntent(mountTable)) != 0 ) {
entries[count].mnt_fsname = stralloc(m->mnt_fsname);
entries[count].mnt_dir = stralloc(m->mnt_dir);
entries[count].mnt_type = stralloc(m->mnt_type);
entries[count].mnt_opts = stralloc(m->mnt_opts);
entries[count].mnt_freq = m->mnt_freq;
entries[count].mnt_passno = m->mnt_passno;
count++;
}
endmntent(mountTable);
if ( (mountTable = setmntent(mtab_file, "w")) ) {
int i;
for ( i = 0; i < count; i++ ) {
int result = ( strcmp(entries[i].mnt_fsname, name) == 0
|| strcmp(entries[i].mnt_dir, name) == 0 );
if ( result )
continue;
else
addmntent(mountTable, &entries[i]);
}
endmntent(mountTable);
}
else if ( errno != EROFS )
perror(mtab_file);
}
/*
* Given a block device, find the mount table entry if that block device
* is mounted.
*
* Given any other file (or directory), find the mount table entry for its
* filesystem.
*/
static struct mntent *
findMountPoint(const char * name, const char * table)
{
struct stat s;
dev_t mountDevice;
FILE* mountTable;
struct mntent* mountEntry;
if ( stat(name, &s) != 0 )
return 0;
if ( (s.st_mode & S_IFMT) == S_IFBLK )
mountDevice = s.st_rdev;
else
mountDevice = s.st_dev;
if ( (mountTable = setmntent(table, "r")) == 0 )
return 0;
while ( (mountEntry = getmntent(mountTable)) != 0 ) {
if ( strcmp(name, mountEntry->mnt_dir) == 0 ||
strcmp(name, mountEntry->mnt_fsname) == 0 ) /* String match. */
break;
if ( stat(mountEntry->mnt_fsname, &s) == 0 &&
s.st_rdev == mountDevice ) /* Match the device. */
break;
if ( stat(mountEntry->mnt_dir, &s) == 0 &&
s.st_dev == mountDevice ) /* Match the directory's mount point. */
break;
}
endmntent(mountTable);
return mountEntry;
}
extern void
write_mtab(char* blockDevice, char* directory,
char* filesystemType, long flags, char* string_flags)
{
FILE *mountTable = setmntent(mtab_file, "a+");
struct mntent m;
if ( mountTable == 0 ) {
perror(mtab_file);
return;
}
if (mountTable) {
int length = strlen(directory);
if ( length > 1 && directory[length - 1] == '/' )
directory[length - 1] = '\0';
if ( filesystemType == 0 ) {
struct mntent * p
= findMountPoint(blockDevice, "/proc/mounts");
if ( p && p->mnt_type )
filesystemType = p->mnt_type;
}
m.mnt_fsname = blockDevice;
m.mnt_dir = directory;
m.mnt_type = filesystemType ? filesystemType : "default";
if (*string_flags) {
m.mnt_opts = string_flags;
} else {
if ( (flags | MS_RDONLY) == flags )
m.mnt_opts = "ro";
else
m.mnt_opts = "rw";
}
m.mnt_freq = 0;
m.mnt_passno = 0;
addmntent(mountTable, &m);
endmntent(mountTable);
}
}
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