New commands: 'mkmountpoint' and 'rmmountpoint'

[libguestfs.git] / daemon / mount.c

diff --git a/daemon/mount.c b/daemon/mount.c
index 4e0ecdb..20811f1 100644 (file)
--- a/daemon/mount.c
+++ b/daemon/mount.c
@@ -1,5 +1,5 @@
 /* libguestfs - the guestfsd daemon
- * Copyright (C) 2009 Red Hat Inc. 
+ * 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
@@ -22,6 +22,8 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <sys/stat.h>
+#include <sys/types.h>
 
 #include "daemon.h"
 #include "actions.h"
@@ -39,13 +41,15 @@ int root_mounted = 0;
  */
 
 int
-do_mount_vfs (const char *options, const char *vfstype,
-             const char *device, const char *mountpoint)
+do_mount_vfs (char *options, char *vfstype,
+             char *device, char *mountpoint)
 {
   int len, r, is_root;
   char *mp;
   char *error;
 
+  IS_DEVICE (device, -1);
+
   is_root = strcmp (mountpoint, "/") == 0;
 
   if (!root_mounted && !is_root) {
@@ -69,6 +73,7 @@ do_mount_vfs (const char *options, const char *vfstype,
   else
     r = command (NULL, &error,
                 "mount", "-o", options, device, mp, NULL);
+  free (mp);
   if (r == -1) {
     reply_with_error ("mount: %s on %s: %s", device, mountpoint, error);
     free (error);
@@ -82,20 +87,20 @@ do_mount_vfs (const char *options, const char *vfstype,
 }
 
 int
-do_mount (const char *device, const char *mountpoint)
+do_mount (char *device, char *mountpoint)
 {
   return do_mount_vfs ("sync,noatime", NULL, device, mountpoint);
 }
 
 int
-do_mount_ro (const char *device, const char *mountpoint)
+do_mount_ro (char *device, char *mountpoint)
 {
   return do_mount_vfs ("ro", NULL, device, mountpoint);
 }
 
 int
-do_mount_options (const char *options, const char *device,
-                 const char *mountpoint)
+do_mount_options (char *options, char *device,
+                 char *mountpoint)
 {
   return do_mount_vfs (options, NULL, device, mountpoint);
 }
@@ -104,15 +109,16 @@ do_mount_options (const char *options, const char *device,
  * is kept updated.
  */
 int
-do_umount (const char *pathordevice)
+do_umount (char *pathordevice)
 {
   int len, freeit = 0, r;
   char *buf;
   char *err;
 
-  if (strncmp (pathordevice, "/dev/", 5) == 0)
-    buf = (char *) pathordevice;
-  else {
+  if (strncmp (pathordevice, "/dev/", 5) == 0) {
+    buf = pathordevice;
+    IS_DEVICE (buf, -1);
+  } else {
     len = strlen (pathordevice) + 9;
     freeit = 1;
     buf = malloc (len);
@@ -138,14 +144,15 @@ do_umount (const char *pathordevice)
   return 0;
 }
 
-char **
-do_mounts (void)
+static char **
+mounts_or_mountpoints (int mp)
 {
   char *out, *err;
   int r;
   char **ret = NULL;
   int size = 0, alloc = 0;
   char *p, *pend, *p2;
+  int len;
 
   r = command (&out, &err, "mount", NULL);
   if (r == -1) {
@@ -175,6 +182,20 @@ do_mounts (void)
        free (out);
        return NULL;
       }
+      if (mp) {
+       p2 += 12;               /* skip " on /sysroot" */
+       len = strcspn (p2, " ");
+
+       if (len == 0)           /* .. just /sysroot, so we turn it into "/" */
+         p2 = (char *) "/";
+       else
+         p2[len] = '\0';
+
+       if (add_string (&ret, &size, &alloc, p2) == -1) {
+         free (out);
+         return NULL;
+       }
+      }
     }
 
     p = pend;
@@ -188,6 +209,18 @@ do_mounts (void)
   return ret;
 }
 
+char **
+do_mounts (void)
+{
+  return mounts_or_mountpoints (0);
+}
+
+char **
+do_mountpoints (void)
+{
+  return mounts_or_mountpoints (1);
+}
+
 /* Unmount everything mounted under /sysroot.
  *
  * We have to unmount in the correct order, so we sort the paths by
@@ -274,3 +307,96 @@ do_umount_all (void)
 
   return 0;
 }
+
+/* Mount using the loopback device.  You can't use the generic
+ * do_mount call for this because the first parameter isn't a
+ * device.
+ */
+int
+do_mount_loop (char *file, char *mountpoint)
+{
+  int len, r;
+  char *buf, *mp;
+  char *error;
+
+  NEED_ROOT (-1);
+  ABS_PATH (file, -1);
+
+  /* We have to prefix /sysroot on both the filename and the mountpoint. */
+  len = strlen (mountpoint) + 9;
+  mp = malloc (len);
+  if (!mp) {
+    reply_with_perror ("malloc");
+    return -1;
+  }
+  snprintf (mp, len, "/sysroot%s", mountpoint);
+
+  len = strlen (file) + 9;
+  buf = malloc (len);
+  if (!file) {
+    reply_with_perror ("malloc");
+    free (mp);
+    return -1;
+  }
+  snprintf (buf, len, "/sysroot%s", file);
+
+  r = command (NULL, &error, "mount", "-o", "loop", buf, mp, NULL);
+  free (mp);
+  free (buf);
+  if (r == -1) {
+    reply_with_error ("mount: %s on %s: %s", file, mountpoint, error);
+    free (error);
+    return -1;
+  }
+
+  return 0;
+}
+
+/* Specialized calls mkmountpoint and rmmountpoint are really
+ * variations on mkdir and rmdir which do no checking and (in the
+ * mkmountpoint case) set the root_mounted flag.
+ */
+int
+do_mkmountpoint (char *path)
+{
+  int r;
+
+  /* NEED_ROOT (-1); - we don't want this test for this call. */
+  ABS_PATH (path, -1);
+
+  CHROOT_IN;
+  r = mkdir (path, 0777);
+  CHROOT_OUT;
+
+  if (r == -1) {
+    reply_with_perror ("mkmountpoint: %s", path);
+    return -1;
+  }
+
+  /* Set the flag so that filesystems can be mounted here,
+   * not just on /sysroot.
+   */
+  root_mounted = 1;
+
+  return 0;
+}
+
+int
+do_rmmountpoint (char *path)
+{
+  int r;
+
+  NEED_ROOT (-1);
+  ABS_PATH (path, -1);
+
+  CHROOT_IN;
+  r = rmdir (path);
+  CHROOT_OUT;
+
+  if (r == -1) {
+    reply_with_perror ("rmmountpoint: %s", path);
+    return -1;
+  }
+
+  return 0;
+}