Whamcloud - gitweb
LU-16067 misc: cleanup compiler warnings
[tools/e2fsprogs.git] / lib / ext2fs / ismounted.c
index bf0c94e..eda04a3 100644 (file)
@@ -1,14 +1,23 @@
 /*
  * ismounted.c --- Check to see if the filesystem was mounted
- * 
+ *
  * Copyright (C) 1995,1996,1997,1998,1999,2000 Theodore Ts'o.
  *
  * %Begin-Header%
- * This file may be redistributed under the terms of the GNU Public
- * License.
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
  * %End-Header%
  */
 
+/* define BSD_SOURCE to make sure we get the major() macro */
+#ifndef _BSD_SOURCE
+#define _BSD_SOURCE
+#endif
+#ifndef _DEFAULT_SOURCE
+#define _DEFAULT_SOURCE        /* since glibc 2.20 _SVID_SOURCE is deprecated */
+#endif
+
+#include "config.h"
 #include <stdio.h>
 #if HAVE_UNISTD_H
 #include <unistd.h>
 #ifdef HAVE_LINUX_FD_H
 #include <linux/fd.h>
 #endif
+#ifdef HAVE_LINUX_LOOP_H
+#include <linux/loop.h>
+#include <sys/ioctl.h>
+#ifdef HAVE_LINUX_MAJOR_H
+#include <linux/major.h>
+#endif /* HAVE_LINUX_MAJOR_H */
+#endif /* HAVE_LINUX_LOOP_H */
 #ifdef HAVE_MNTENT_H
 #include <mntent.h>
 #endif
 #endif /* HAVE_GETMNTINFO */
 #include <string.h>
 #include <sys/stat.h>
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+#ifdef HAVE_SYS_SYSMACROS_H
+#include <sys/sysmacros.h>
+#endif
+#include <dirent.h>
 
 #include "ext2_fs.h"
 #include "ext2fs.h"
+#include "ext2fsP.h"
+
+#ifdef HAVE_SETMNTENT
+/*
+ * Check to see if a regular file is mounted.
+ * If /etc/mtab/ is a symlink of /proc/mounts, you will need the following check
+ * because the name in /proc/mounts is a loopback device not a regular file.
+ */
+static int check_loop_mounted(const char *mnt_fsname, dev_t mnt_rdev,
+                               dev_t file_dev, ino_t file_ino)
+{
+#if defined(HAVE_LINUX_LOOP_H) && defined(HAVE_LINUX_MAJOR_H)
+       struct loop_info64 loopinfo = {0, };
+       int loop_fd, ret;
+
+       if (major(mnt_rdev) == LOOP_MAJOR) {
+               loop_fd = open(mnt_fsname, O_RDONLY);
+               if (loop_fd < 0)
+                       return -1;
+
+               ret = ioctl(loop_fd, LOOP_GET_STATUS64, &loopinfo);
+               close(loop_fd);
+               if (ret < 0)
+                       return -1;
+
+               if (file_dev == loopinfo.lo_device &&
+                               file_ino == loopinfo.lo_inode)
+                       return 1;
+       }
+#endif /* defined(HAVE_LINUX_LOOP_H) && defined(HAVE_LINUX_MAJOR_H) */
+       return 0;
+}
 
-#ifdef HAVE_MNTENT_H
 /*
  * Helper function which checks a file in /etc/mtab format to see if a
  * filesystem is mounted.  Returns an error if the file doesn't exist
- * or can't be opened.  
+ * or can't be opened.
  */
-static errcode_t check_mntent_file(const char *mtab_file, const char *file, 
+static errcode_t check_mntent_file(const char *mtab_file, const char *file,
                                   int *mount_flags, char *mtpt, int mtlen)
 {
-       FILE * f;
-       struct mntent * mnt;
-       int     fd;
+       struct mntent   *mnt;
+       struct stat     st_buf, dir_st_buf;
+       errcode_t       retval = 0;
+       dev_t           file_dev=0, file_rdev=0;
+       ino_t           file_ino=0;
+       FILE            *f;
+       int             fd;
 
        *mount_flags = 0;
-       if ((f = setmntent (mtab_file, "r")) == NULL)
+
+       if ((f = setmntent (mtab_file, "r")) == NULL) {
+               if (errno == ENOENT) {
+                       if (getenv("EXT2FS_NO_MTAB_OK"))
+                               return 0;
+                       else
+                               return EXT2_ET_NO_MTAB_FILE;
+               }
                return errno;
-       while ((mnt = getmntent (f)) != NULL)
-               if (strcmp(file, mnt->mnt_fsname) == 0)
+       }
+       if (stat(file, &st_buf) == 0) {
+               if (ext2fsP_is_disk_device(st_buf.st_mode)) {
+#ifndef __GNU__ /* The GNU hurd is broken with respect to stat devices */
+                       file_rdev = st_buf.st_rdev;
+#endif /* __GNU__ */
+               } else {
+                       file_dev = st_buf.st_dev;
+                       file_ino = st_buf.st_ino;
+               }
+       }
+       while ((mnt = getmntent (f)) != NULL) {
+               if (mnt->mnt_fsname[0] != '/')
+                       continue;
+               if (strcmp(file, mnt->mnt_fsname) == 0) {
+                       if (stat(mnt->mnt_dir, &st_buf) != 0)
+                               continue;
+                       if (file_rdev && (file_rdev != st_buf.st_dev)) {
+#ifdef DEBUG
+                               printf("Bogus entry in %s!  "
+                                      "(%s is not mounted on %s)\n",
+                                      mtab_file, file, mnt->mnt_dir);
+#endif /* DEBUG */
+                               continue;
+                       }
                        break;
+               }
+               if (stat(mnt->mnt_fsname, &st_buf) == 0) {
+                       if (ext2fsP_is_disk_device(st_buf.st_mode)) {
+#ifndef __GNU__
+                               if (file_rdev &&
+                                   (file_rdev == st_buf.st_rdev)) {
+                                       if (stat(mnt->mnt_dir,
+                                                &dir_st_buf) != 0)
+                                               continue;
+                                       if (file_rdev == dir_st_buf.st_dev)
+                                               break;
+                               }
+                               if (check_loop_mounted(mnt->mnt_fsname,
+                                               st_buf.st_rdev, file_dev,
+                                               file_ino) == 1)
+                                       break;
+#endif /* __GNU__ */
+                       } else {
+                               if (file_dev && ((file_dev == st_buf.st_dev) &&
+                                                (file_ino == st_buf.st_ino)))
+                                       break;
+                       }
+               }
+       }
 
        if (mnt == 0) {
 #ifndef __GNU__ /* The GNU hurd is broken with respect to stat devices */
-               struct stat st_root, st_file;
                /*
                 * Do an extra check to see if this is the root device.  We
-                * can't trust /etc/fstab, and /proc/mounts will only list
+                * can't trust /etc/mtab, and /proc/mounts will only list
                 * /dev/root for the root filesystem.  Argh.  Instead we
                 * check if the given device has the same major/minor number
                 * as the device that the root directory is on.
                 */
-               if (stat("/", &st_root) == 0 && stat(file, &st_file) == 0) {
-                       if (st_root.st_dev == st_file.st_rdev) {
+               if (file_rdev && stat("/", &st_buf) == 0) {
+                       if (st_buf.st_dev == file_rdev) {
                                *mount_flags = EXT2_MF_MOUNTED;
                                if (mtpt)
                                        strncpy(mtpt, "/", mtlen);
                                goto is_root;
                        }
                }
-#endif
-               endmntent (f);
-               return 0;
+#endif /* __GNU__ */
+               goto errout;
        }
        *mount_flags = EXT2_MF_MOUNTED;
-       
+
+#ifdef MNTOPT_RO
        /* Check to see if the ro option is set */
        if (hasmntopt(mnt, MNTOPT_RO))
                *mount_flags |= EXT2_MF_READONLY;
+#endif
 
        if (mtpt)
                strncpy(mtpt, mnt->mnt_dir, mtlen);
@@ -92,16 +204,26 @@ static errcode_t check_mntent_file(const char *mtab_file, const char *file,
         */
        if (!strcmp(mnt->mnt_dir, "/")) {
 is_root:
+#define TEST_FILE "/.ismount-test-file"
                *mount_flags |= EXT2_MF_ISROOT;
-               fd = open(MOUNTED, O_RDWR);
+               fd = open(TEST_FILE, O_RDWR|O_CREAT, 0600);
                if (fd < 0) {
                        if (errno == EROFS)
                                *mount_flags |= EXT2_MF_READONLY;
                } else
                        close(fd);
+               (void) unlink(TEST_FILE);
        }
+
+       if (mnt && mnt->mnt_type &&
+           (!strcmp(mnt->mnt_type, "ext4") ||
+            !strcmp(mnt->mnt_type, "ext3") ||
+            !strcmp(mnt->mnt_type, "ext2")))
+               *mount_flags |= EXT2_MF_EXTFS;
+       retval = 0;
+errout:
        endmntent (f);
-       return 0;
+       return retval;
 }
 
 static errcode_t check_mntent(const char *file, int *mount_flags,
@@ -109,17 +231,32 @@ static errcode_t check_mntent(const char *file, int *mount_flags,
 {
        errcode_t       retval;
 
+#ifdef DEBUG
+       retval = check_mntent_file("/tmp/mtab", file, mount_flags,
+                                  mtpt, mtlen);
+       if (retval == 0)
+               return 0;
+#endif /* DEBUG */
 #ifdef __linux__
        retval = check_mntent_file("/proc/mounts", file, mount_flags,
                                   mtpt, mtlen);
        if (retval == 0)
                return 0;
-#endif
+#endif /* __linux__ */
+#if defined(MOUNTED) || defined(_PATH_MOUNTED)
+#ifndef MOUNTED
+#define MOUNTED _PATH_MOUNTED
+#endif /* MOUNTED */
        retval = check_mntent_file(MOUNTED, file, mount_flags, mtpt, mtlen);
        return retval;
+#else
+       *mount_flags = 0;
+       return 0;
+#endif /* defined(MOUNTED) || defined(_PATH_MOUNTED) */
 }
 
-#elif defined(HAVE_GETMNTINFO)
+#else
+#if defined(HAVE_GETMNTINFO)
 
 static errcode_t check_getmntinfo(const char *file, int *mount_flags,
                                  char *mtpt, int mtlen)
@@ -137,7 +274,7 @@ static errcode_t check_getmntinfo(const char *file, int *mount_flags,
         s1 = file;
         if (strncmp(_PATH_DEV, s1, len) == 0)
                 s1 += len;
+
        *mount_flags = 0;
         while (--n >= 0) {
                 s2 = mp->f_mntfromname;
@@ -156,12 +293,261 @@ static errcode_t check_getmntinfo(const char *file, int *mount_flags,
        return 0;
 }
 #endif /* HAVE_GETMNTINFO */
+#endif /* HAVE_SETMNTENT */
+
+/*
+ * Check to see if we're dealing with the swap device.
+ */
+static int is_swap_device(const char *file)
+{
+       FILE            *f;
+       char            buf[1024], *cp;
+       dev_t           file_dev;
+       struct stat     st_buf;
+       int             ret = 0;
+
+       file_dev = 0;
+#ifndef __GNU__ /* The GNU hurd is broken with respect to stat devices */
+       if ((stat(file, &st_buf) == 0) &&
+           ext2fsP_is_disk_device(st_buf.st_mode))
+               file_dev = st_buf.st_rdev;
+#endif /* __GNU__ */
+
+       if (!(f = fopen("/proc/swaps", "r")))
+               return 0;
+       /* Skip the first line */
+       if (!fgets(buf, sizeof(buf), f))
+               goto leave;
+       if (*buf && strncmp(buf, "Filename\t", 9))
+               /* Linux <=2.6.19 contained a bug in the /proc/swaps
+                * code where the header would not be displayed
+                */
+               goto valid_first_line;
+
+       while (fgets(buf, sizeof(buf), f)) {
+valid_first_line:
+               if ((cp = strchr(buf, ' ')) != NULL)
+                       *cp = 0;
+               if ((cp = strchr(buf, '\t')) != NULL)
+                       *cp = 0;
+               if (strcmp(buf, file) == 0) {
+                       ret++;
+                       break;
+               }
+#ifndef __GNU__
+               if (file_dev && (stat(buf, &st_buf) == 0) &&
+                   ext2fsP_is_disk_device(st_buf.st_mode) &&
+                   file_dev == st_buf.st_rdev) {
+                       ret++;
+                       break;
+               }
+#endif         /* __GNU__ */
+       }
+
+leave:
+       fclose(f);
+       return ret;
+}
+
+static int check_lustre_zfs(char *mnt_device, const char *real_devname)
+{
+       char *real_mnt_device, *buf, *ptr;
+       FILE *fp;
+       int rc = 0;
+
+       real_mnt_device = malloc(PATH_MAX);
+       if (real_mnt_device == NULL) {
+               fprintf(stderr, "Cannot allocate memory to store path\n");
+               return 1;
+       }
+
+       buf = malloc(PATH_MAX);
+       if (buf == NULL) {
+               fprintf(stderr, "Cannot allocate memory to store command\n");
+               free(real_mnt_device);
+               return 1;
+       }
+
+       /* Get the pool name from mnt_device */
+       ptr = strchr(mnt_device, '/');
+       if (ptr)
+               *ptr = '\0';
+
+       memset(buf, 0, PATH_MAX);
+       sprintf(buf, "zpool list -Hv %s", mnt_device);
+
+       fp = popen(buf, "r");
+       if (fp) {
+               int line = 0;
+               while (!feof(fp)) {
+                       memset(buf, 0, PATH_MAX);
+                       if (fscanf(fp, "%s%*[^\n]", buf) < 1)
+                               break;
+                       /* skip the first line */
+                       if (line++ == 0)
+                               continue;
+                       /* skip empty line */
+                       if (strlen(buf) == 0)
+                               continue;
+
+                       if (realpath(buf, real_mnt_device) == NULL)
+                               continue;
+                       if (strcmp(real_devname, real_mnt_device) == 0) {
+                               fprintf(stderr, "device %s mounted by Lustre\n",
+                                       real_devname);
+                               rc = -1;
+                               break;
+                       }
+               }
+               pclose(fp);
+       }
+
+       return rc;
+}
+
+static int check_lustre_ldiskfs(const char *mnt_device,
+                               const char *real_devname)
+{
+       char *real_mnt_device;
+
+       real_mnt_device = malloc(PATH_MAX);
+       if (real_mnt_device == NULL) {
+               fprintf(stderr, "Cannot allocate memory to store path\n");
+               return 1;
+       }
+
+       memset(real_mnt_device, 0, PATH_MAX);
+       if (realpath(mnt_device, real_mnt_device) == NULL) {
+               fprintf(stderr, "Cannot resolve mntdev %s\n", mnt_device);
+               free(real_mnt_device);
+               return 1;
+       }
+
+       if (strcmp(real_devname, real_mnt_device) == 0) {
+               fprintf(stderr, "device %s mounted by lustre\n", real_devname);
+               free(real_mnt_device);
+               return -1;
+       }
+
+       free(real_mnt_device);
+       return 0;
+}
+
+static int check_lustre_proc_vals(const char *procname,const char *real_devname)
+{
+       struct dirent *direntp;
+       DIR *dirp;
+       int rc = 0;
+       char  *mnt_device, *proc_val;
+
+       mnt_device = malloc(PATH_MAX);
+       if (mnt_device == NULL) {
+               fprintf(stderr, "Cannot allocate memory to store device\n");
+               return 1;
+       }
+       proc_val = malloc(PATH_MAX);
+       if (proc_val == NULL) {
+               fprintf(stderr, "Cannot allocate memory to store proc\n");
+               free(mnt_device);
+               return 1;
+       }
+
+       dirp = opendir(procname);
+       if (dirp) {
+               do {
+                       int fd, numr;
+                       char *ptr;
+
+                       direntp = readdir(dirp);
+                       if (direntp == NULL)
+                               break;
+                       if ((strncmp(direntp->d_name, ".", 1) == 0) ||
+                           (strncmp(direntp->d_name, "..", 2) == 0)) {
+                               continue;
+                       }
+
+                       memset(proc_val, 0, PATH_MAX);
+                       snprintf(proc_val, PATH_MAX, "%s/%s/mntdev", procname,
+                                direntp->d_name);
+                       fd = open(proc_val, O_RDONLY);
+                       if (fd < 0)  {
+                               if (errno == ENOENT || errno == ENOTDIR)
+                                       continue;
+                               fprintf(stderr, "Cannot open %s: %s\n",
+                                       proc_val, strerror(errno));
+                               rc = 1;
+                               break;
+                       }
+
+                       memset(mnt_device, 0, PATH_MAX);
+                       numr = read(fd, mnt_device, PATH_MAX);
+                       if (numr < 0) {
+                               fprintf(stderr, "Failure to get mntdev info\n");
+                               rc = 1;
+                               close(fd);
+                               break;
+                       }
+                       close(fd);
+
+                       ptr = strchr(mnt_device, '\n');
+                       if (ptr)
+                               *ptr = '\0';
+
+                       if (strstr(procname, "osd-zfs") != NULL)
+                               rc = check_lustre_zfs(mnt_device, real_devname);
+                       else
+                               rc = check_lustre_ldiskfs(mnt_device,
+                                                         real_devname);
+
+               } while (direntp != NULL && rc == 0);
+
+               closedir(dirp);
+       }
+
+       free(proc_val);
+       free(mnt_device);
+
+       return rc;
+}
+
+static errcode_t check_if_lustre_mounted(const char *device, int *mount_flags)
+{
+       char *real_device;
+       int rc = 0;
+
+       real_device = malloc(PATH_MAX);
+       if (real_device == NULL) {
+               fprintf(stderr, "Cannot allocate memory to store path\n");
+               return EXT2_ET_NO_MEMORY;
+       }
+
+       if (realpath(device, real_device) == NULL) {
+               fprintf(stderr, "Cannot resolve path %s\n", device);
+               rc = EXT2_ET_BAD_DEVICE_NAME;
+               goto out_free;
+       }
+
+       rc = check_lustre_proc_vals("/proc/fs/lustre/osd-ldiskfs", real_device);
+       if (!rc)
+               rc = check_lustre_proc_vals("/proc/fs/lustre/osd-zfs",
+                                           real_device);
+       if (rc)
+               *mount_flags |= EXT2_MF_MOUNTED;
+
+out_free:
+       free(real_device);
+
+       return rc;
+}
+
 
 /*
- * ext2fs_check_mount_point() returns 1 if the device is mounted, 0
- * otherwise.  If mtpt is non-NULL, the directory where the device is
- * mounted is copied to where mtpt is pointing, up to mtlen
- * characters.
+ * ext2fs_check_mount_point() fills determines if the device is
+ * mounted or otherwise busy, and fills in mount_flags with one or
+ * more of the following flags: EXT2_MF_MOUNTED, EXT2_MF_ISROOT,
+ * EXT2_MF_READONLY, EXT2_MF_SWAP, and EXT2_MF_BUSY.  If mtpt is
+ * non-NULL, the directory where the device is mounted is copied to
+ * where mtpt is pointing, up to mtlen characters.
  */
 #ifdef __TURBOC__
  #pragma argsused
@@ -169,27 +555,80 @@ static errcode_t check_getmntinfo(const char *file, int *mount_flags,
 errcode_t ext2fs_check_mount_point(const char *device, int *mount_flags,
                                  char *mtpt, int mtlen)
 {
-#ifdef HAVE_MNTENT_H
-       return check_mntent(device, mount_flags, mtpt, mtlen);
-#else 
+       errcode_t       retval = 0;
+       int             busy = 0;
+
+       if (getenv("EXT2FS_PRETEND_RO_MOUNT")) {
+               *mount_flags = EXT2_MF_MOUNTED | EXT2_MF_READONLY;
+               if (getenv("EXT2FS_PRETEND_ROOTFS"))
+                       *mount_flags = EXT2_MF_ISROOT;
+               return 0;
+       }
+       if (getenv("EXT2FS_PRETEND_RW_MOUNT")) {
+               *mount_flags = EXT2_MF_MOUNTED;
+               if (getenv("EXT2FS_PRETEND_ROOTFS"))
+                       *mount_flags = EXT2_MF_ISROOT;
+               return 0;
+       }
+
+#ifdef __linux__ /* This only works on Linux 2.6+ systems */
+       {
+               struct stat st_buf;
+
+               if (stat(device, &st_buf) == 0 &&
+                   ext2fsP_is_disk_device(st_buf.st_mode)) {
+                       int fd = open(device, O_RDONLY | O_EXCL);
+
+                       if (fd >= 0) {
+                               /*
+                                * The device is not busy so it's
+                                * definitelly not mounted. No need to
+                                * to perform any more checks.
+                                */
+                               close(fd);
+                               *mount_flags = 0;
+                               return 0;
+                       } else if (errno == EBUSY) {
+                               busy = 1;
+                       }
+               }
+       }
+#endif
+
+       if (is_swap_device(device)) {
+               *mount_flags = EXT2_MF_MOUNTED | EXT2_MF_SWAP;
+               if (mtpt)
+                       strncpy(mtpt, "<swap>", mtlen);
+       } else {
+#ifdef HAVE_SETMNTENT
+               retval = check_mntent(device, mount_flags, mtpt, mtlen);
+#else
 #ifdef HAVE_GETMNTINFO
-       return check_getmntinfo(device, mount_flags, mtpt, mtlen);
+               retval = check_getmntinfo(device, mount_flags, mtpt, mtlen);
 #else
-#warning "Can't use getmntent or getmntinfo to check for mounted filesystems!"
-       *mount_flags = 0;
-       return 0;
+#if defined(__GNUC__) && !defined(_WIN32)
+ #warning "Can't use getmntent or getmntinfo to check for mounted filesystems!"
+#endif
+               *mount_flags = 0;
 #endif /* HAVE_GETMNTINFO */
-#endif /* HAVE_MNTENT_H */
+#endif /* HAVE_SETMNTENT */
+       }
+       if (retval)
+               return retval;
+
+       if (busy)
+               *mount_flags |= EXT2_MF_BUSY;
+
+       retval = check_if_lustre_mounted(device, mount_flags);
+
+       return 0;
 }
 
 /*
- * ext2fs_check_if_mounted() sets the mount_flags EXT2_MF_MOUNTED and
+ * ext2fs_check_if_mounted() sets the mount_flags EXT2_MF_MOUNTED,
  * EXT2_MF_READONLY, and EXT2_MF_ROOT
- * 
+ *
  */
-#ifdef __TURBOC__
- #pragma argsused
-#endif
 errcode_t ext2fs_check_if_mounted(const char *file, int *mount_flags)
 {
        return ext2fs_check_mount_point(file, mount_flags, NULL, 0);
@@ -199,28 +638,35 @@ errcode_t ext2fs_check_if_mounted(const char *file, int *mount_flags)
 int main(int argc, char **argv)
 {
        int     retval, mount_flags;
-       
+       char    mntpt[80];
+
        if (argc < 2) {
                fprintf(stderr, "Usage: %s device\n", argv[0]);
                exit(1);
        }
 
-       retval = ext2fs_check_if_mounted(argv[1], &mount_flags);
+       add_error_table(&et_ext2_error_table);
+       mntpt[0] = 0;
+       retval = ext2fs_check_mount_point(argv[1], &mount_flags,
+                                         mntpt, sizeof(mntpt));
        if (retval) {
                com_err(argv[0], retval,
                        "while calling ext2fs_check_if_mounted");
                exit(1);
        }
        printf("Device %s reports flags %02x\n", argv[1], mount_flags);
+       if (mount_flags & EXT2_MF_BUSY)
+               printf("\t%s is apparently in use.\n", argv[1]);
        if (mount_flags & EXT2_MF_MOUNTED)
                printf("\t%s is mounted.\n", argv[1]);
-       
+       if (mount_flags & EXT2_MF_SWAP)
+               printf("\t%s is a swap device.\n", argv[1]);
        if (mount_flags & EXT2_MF_READONLY)
                printf("\t%s is read-only.\n", argv[1]);
-       
        if (mount_flags & EXT2_MF_ISROOT)
                printf("\t%s is the root filesystem.\n", argv[1]);
-       
+       if (mntpt[0])
+               printf("\t%s is mounted on %s.\n", argv[1], mntpt);
        exit(0);
 }
-#endif
+#endif /* DEBUG */