Comments; NTFS hardlinks
authorEric Biggers <ebiggers3@gmail.com>
Tue, 21 Aug 2012 23:26:03 +0000 (18:26 -0500)
committerEric Biggers <ebiggers3@gmail.com>
Tue, 21 Aug 2012 23:26:03 +0000 (18:26 -0500)
src/ntfs-apply.c

index 300c30819af778f2fff1ec4543e7e2940c0ac833..a1daf22f204e9d1886c09b50d64121f9d078c545 100644 (file)
@@ -44,6 +44,9 @@ extern int _ntfs_set_file_security(ntfs_volume *vol, ntfs_inode *ni,
                                   u32 selection, const char *attr);
 extern int _ntfs_set_file_attributes(ntfs_inode *ni, s32 attrib);
 
                                   u32 selection, const char *attr);
 extern int _ntfs_set_file_attributes(ntfs_inode *ni, s32 attrib);
 
+/* 
+ * Extracts a WIM resource to a NTFS attribute.
+ */
 static int extract_resource_to_ntfs_attr(WIMStruct *w, const struct resource_entry *entry, 
                                         ntfs_attr *na)
 {
 static int extract_resource_to_ntfs_attr(WIMStruct *w, const struct resource_entry *entry, 
                                         ntfs_attr *na)
 {
@@ -76,6 +79,14 @@ static int extract_resource_to_ntfs_attr(WIMStruct *w, const struct resource_ent
        return 0;
 }
 
        return 0;
 }
 
+/* Writes the data streams to a NTFS file
+ *
+ * @ni:             The NTFS inode for the file.
+ * @dentry:  The directory entry in the WIM file.
+ * @w:      The WIMStruct for the WIM containing the image we are applying.
+ *
+ * Returns 0 on success, nonzero on failure.
+ */
 static int write_ntfs_data_streams(ntfs_inode *ni, const struct dentry *dentry,
                                   WIMStruct *w)
 {
 static int write_ntfs_data_streams(ntfs_inode *ni, const struct dentry *dentry,
                                   WIMStruct *w)
 {
@@ -107,6 +118,49 @@ static int write_ntfs_data_streams(ntfs_inode *ni, const struct dentry *dentry,
        return 0;
 }
 
        return 0;
 }
 
+/*
+ * Makes a NTFS hard link
+ *
+ * It is named @from_dentry->file_name and is located under the directory
+ * specified by @dir_ni, and it is made to point to the previously extracted
+ * file located at @to_dentry->extracted_file.
+ *
+ * Return 0 on success, nonzero on failure.
+ */
+static int wim_apply_hardlink_ntfs(const struct dentry *from_dentry,
+                                  const struct dentry *to_dentry,
+                                  ntfs_inode *dir_ni)
+{
+       int ret;
+       ntfs_inode *to_ni;
+
+       DEBUG("Extracting NTFS hard link `%s' => `%s'",
+             from_dentry->full_path_utf8, to_dentry->extracted_file);
+
+       to_ni = ntfs_pathname_to_inode(dir_ni->vol, NULL,
+                                      to_dentry->extracted_file);
+       if (!to_ni) {
+               ERROR_WITH_ERRNO("Could not find NTFS inode for `%s'",
+                                to_dentry->extracted_file);
+               return WIMLIB_ERR_NTFS_3G;
+       }
+       ret = ntfs_link(to_ni, dir_ni,
+                       (ntfschar*)from_dentry->file_name,
+                       from_dentry->file_name_len / 2);
+       if (ret != 0) {
+               ERROR_WITH_ERRNO("Could not create hard link `%s' => `%s'",
+                                from_dentry->full_path_utf8,
+                                to_dentry->extracted_file);
+               ret = WIMLIB_ERR_NTFS_3G;
+       }
+       if (ntfs_inode_close(to_ni) != 0) {
+               ERROR_WITH_ERRNO("Failed to close NTFS inode for `%s'",
+                                to_dentry->extracted_file);
+               ret = WIMLIB_ERR_NTFS_3G;
+       }
+       return ret;
+}
+
 /* 
  * Applies a WIM dentry to a NTFS filesystem.
  *
 /* 
  * Applies a WIM dentry to a NTFS filesystem.
  *
@@ -116,20 +170,48 @@ static int write_ntfs_data_streams(ntfs_inode *ni, const struct dentry *dentry,
  *
  * @return:  0 on success; nonzero on failure.
  */
  *
  * @return:  0 on success; nonzero on failure.
  */
-static int __ntfs_apply_dentry(struct dentry *dentry, ntfs_inode *dir_ni,
-                              WIMStruct *w)
+static int do_wim_apply_dentry_ntfs(struct dentry *dentry, ntfs_inode *dir_ni,
+                                   WIMStruct *w)
 {
        ntfs_inode *ni;
        int ret;
        mode_t type;
 
 {
        ntfs_inode *ni;
        int ret;
        mode_t type;
 
-       print_dentry(dentry, w->lookup_table);
-
-       if (dentry_is_directory(dentry))
+       if (dentry_is_directory(dentry)) {
                type = S_IFDIR;
                type = S_IFDIR;
-       else
+       } else {
                type = S_IFREG;
                type = S_IFREG;
+               const struct list_head *head = &dentry->link_group_list;
+               if (head->next != head) {
+                       /* This dentry is one of a hard link set of at least 2
+                        * dentries.  If one of the other dentries has already
+                        * been extracted, make a hard link to the file
+                        * corresponding to this already-extracted directory.
+                        * Otherwise, extract the file, and set the
+                        * dentry->extracted_file field so that other dentries
+                        * in the hard link group can link to it. */
+                       struct dentry *other;
+                       list_for_each_entry(other, head, link_group_list) {
+                               if (other->extracted_file) {
+                                       return wim_apply_hardlink_ntfs(
+                                                       dentry, other, dir_ni);
+                               }
+                       }
+               }
+               FREE(dentry->extracted_file);
+               dentry->extracted_file = STRDUP(dentry->full_path_utf8);
+               if (!dentry->extracted_file) {
+                       ERROR("Failed to allocate memory for filename");
+                       return WIMLIB_ERR_NOMEM;
+               }
+       }
 
 
+       /* 
+        * Create a directory or file.
+        *
+        * Note: if it's a reparse point (such as a symbolic link), we still
+        * pass S_IFREG here, since we manually set the reparse data later.
+        */
        ni = ntfs_create(dir_ni, 0, (ntfschar*)dentry->file_name,
                         dentry->file_name_len / 2, type);
 
        ni = ntfs_create(dir_ni, 0, (ntfschar*)dentry->file_name,
                         dentry->file_name_len / 2, type);
 
@@ -140,6 +222,8 @@ static int __ntfs_apply_dentry(struct dentry *dentry, ntfs_inode *dir_ni,
                goto out;
        }
 
                goto out;
        }
 
+       /* Write the data streams, unless this is a directory or reparse point
+        * */
        if (!dentry_is_directory(dentry) &&
             !(dentry->attributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
                ret = write_ntfs_data_streams(ni, dentry, w);
        if (!dentry_is_directory(dentry) &&
             !(dentry->attributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
                ret = write_ntfs_data_streams(ni, dentry, w);
@@ -147,9 +231,8 @@ static int __ntfs_apply_dentry(struct dentry *dentry, ntfs_inode *dir_ni,
                        goto out;
        }
 
                        goto out;
        }
 
-       DEBUG("Setting file attributes 0x%x on `%s'",
-             dentry->attributes,
-             dentry->full_path_utf8);
+       DEBUG("Setting NTFS file attributes on `%s' to %#"PRIx32,
+             dentry->full_path_utf8, dentry->attributes);
 
        if (!_ntfs_set_file_attributes(ni, dentry->attributes)) {
                ERROR("Failed to set NTFS file attributes on `%s'",
 
        if (!_ntfs_set_file_attributes(ni, dentry->attributes)) {
                ERROR("Failed to set NTFS file attributes on `%s'",
@@ -204,7 +287,7 @@ out:
        return ret;
 }
 
        return ret;
 }
 
-static int ntfs_apply_dentry(struct dentry *dentry, void *arg)
+static int wim_apply_dentry_ntfs(struct dentry *dentry, void *arg)
 {
        struct ntfs_apply_args *args = arg;
        ntfs_volume *vol             = args->vol;
 {
        struct ntfs_apply_args *args = arg;
        ntfs_volume *vol             = args->vol;
@@ -212,25 +295,28 @@ static int ntfs_apply_dentry(struct dentry *dentry, void *arg)
        WIMStruct *w                 = args->w;
        ntfs_inode *dir_ni;
        int ret;
        WIMStruct *w                 = args->w;
        ntfs_inode *dir_ni;
        int ret;
+       char *p;
+       char orig;
+       const char *dir_name;
+
+       wimlib_assert(dentry->full_path_utf8);
 
 
-       DEBUG("Applying `%s'", dentry->full_path_utf8);
+       DEBUG("Applying dentry `%s' to NTFS", dentry->full_path_utf8);
 
        if (dentry_is_root(dentry))
                return 0;
 
 
        if (dentry_is_root(dentry))
                return 0;
 
-       if (extract_flags & WIMLIB_EXTRACT_FLAG_VERBOSE) {
-               wimlib_assert(dentry->full_path_utf8);
+       if (extract_flags & WIMLIB_EXTRACT_FLAG_VERBOSE)
                puts(dentry->full_path_utf8);
                puts(dentry->full_path_utf8);
-       }
 
 
-       char *p = dentry->full_path_utf8 + dentry->full_path_utf8_len;
+       p = dentry->full_path_utf8 + dentry->full_path_utf8_len;
        do {
                p--;
        } while (*p != '/');
 
        do {
                p--;
        } while (*p != '/');
 
-       char orig = *p;
+       orig = *p;
        *p = '\0';
        *p = '\0';
-       const char *dir_name = dentry->full_path_utf8;
+       dir_name = dentry->full_path_utf8;
 
        dir_ni = ntfs_pathname_to_inode(vol, NULL, dir_name);
        *p = orig;
 
        dir_ni = ntfs_pathname_to_inode(vol, NULL, dir_name);
        *p = orig;
@@ -241,7 +327,7 @@ static int ntfs_apply_dentry(struct dentry *dentry, void *arg)
        }
        DEBUG("Found NTFS inode for `%s'", dir_name);
 
        }
        DEBUG("Found NTFS inode for `%s'", dir_name);
 
-       ret = __ntfs_apply_dentry(dentry, dir_ni, w);
+       ret = do_wim_apply_dentry_ntfs(dentry, dir_ni, w);
 
        if (ntfs_inode_close(dir_ni) != 0) {
                if (ret == 0)
 
        if (ntfs_inode_close(dir_ni) != 0) {
                if (ret == 0)
@@ -252,7 +338,7 @@ static int ntfs_apply_dentry(struct dentry *dentry, void *arg)
 
 }
 
 
 }
 
-static int do_ntfs_apply(WIMStruct *w, const char *device, int extract_flags)
+static int do_wim_apply_image_ntfs(WIMStruct *w, const char *device, int extract_flags)
 {
        ntfs_volume *vol;
        int ret;
 {
        ntfs_volume *vol;
        int ret;
@@ -267,7 +353,7 @@ static int do_ntfs_apply(WIMStruct *w, const char *device, int extract_flags)
                .extract_flags = extract_flags,
                .w             = w,
        };
                .extract_flags = extract_flags,
                .w             = w,
        };
-       ret = for_dentry_in_tree(wim_root_dentry(w), ntfs_apply_dentry,
+       ret = for_dentry_in_tree(wim_root_dentry(w), wim_apply_dentry_ntfs,
                                 &args);
        if (ntfs_umount(vol, FALSE) != 0) {
                ERROR_WITH_ERRNO("Failed to unmount NTFS volume");
                                 &args);
        if (ntfs_umount(vol, FALSE) != 0) {
                ERROR_WITH_ERRNO("Failed to unmount NTFS volume");
@@ -308,7 +394,7 @@ WIMLIBAPI int wimlib_apply_image_to_ntfs_volume(WIMStruct *w, int image,
                return WIMLIB_ERR_NOT_ROOT;
        }
 #endif
                return WIMLIB_ERR_NOT_ROOT;
        }
 #endif
-       return do_ntfs_apply(w, device, flags);
+       return do_wim_apply_image_ntfs(w, device, flags);
 }
 
 #else /* WITH_NTFS_3G */
 }
 
 #else /* WITH_NTFS_3G */