]> wimlib.net Git - wimlib/blobdiff - src/unix_apply.c
unix_apply.c: extract non-link directory reparse points as directories
[wimlib] / src / unix_apply.c
index b1d914827beec90c9ac3f6e69067cd19161eaaa9..f1962d9884b63752892217f3eed71b29393a777c 100644 (file)
  */
 
 /*
- * Copyright (C) 2012, 2013 Eric Biggers
+ * Copyright (C) 2012, 2013, 2014 Eric Biggers
  *
- * This file is part of wimlib, a library for working with WIM files.
+ * This file is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU Lesser General Public License as published by the Free
+ * Software Foundation; either version 3 of the License, or (at your option) any
+ * later version.
  *
- * wimlib 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 3 of the License, or (at your option)
- * any later version.
- *
- * wimlib 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
+ * This file 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 Lesser General Public License for more
  * details.
  *
- * You should have received a copy of the GNU General Public License
- * along with wimlib; if not, see http://www.gnu.org/licenses/.
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this file; if not, see http://www.gnu.org/licenses/.
  */
 
-#ifndef __WIN32__
-
 #ifdef HAVE_CONFIG_H
 #  include "config.h"
 #endif
 
-#include <dirent.h>
 #include <errno.h>
 #include <fcntl.h>
-#include <string.h>
+#include <stdlib.h>
 #include <sys/stat.h>
 #include <sys/time.h>
+#include <sys/types.h>
 #include <unistd.h>
-#ifdef HAVE_UTIME_H
-#  include <utime.h>
-#endif
 
 #include "wimlib/apply.h"
+#include "wimlib/assert.h"
+#include "wimlib/blob_table.h"
+#include "wimlib/dentry.h"
 #include "wimlib/error.h"
-#include "wimlib/lookup_table.h"
+#include "wimlib/file_io.h"
 #include "wimlib/reparse.h"
 #include "wimlib/timestamp.h"
+#include "wimlib/unix_data.h"
+
+/* We don't require O_NOFOLLOW, but the advantage of having it is that if we
+ * need to extract a file to a location at which there exists a symbolic link,
+ * open(..., O_NOFOLLOW | ...) recognizes the symbolic link rather than
+ * following it and creating the file somewhere else.  (Equivalent to
+ * FILE_OPEN_REPARSE_POINT on Windows.)  */
+#ifndef O_NOFOLLOW
+#  define O_NOFOLLOW 0
+#endif
 
-/* Returns the number of components of @path.  */
-static unsigned
-get_num_path_components(const char *path)
+static int
+unix_get_supported_features(const char *target,
+                           struct wim_features *supported_features)
 {
-       unsigned num_components = 0;
-       while (*path) {
-               while (*path == '/')
-                       path++;
-               if (*path)
-                       num_components++;
-               while (*path && *path != '/')
-                       path++;
+       supported_features->hard_links = 1;
+       supported_features->symlink_reparse_points = 1;
+       supported_features->unix_data = 1;
+       supported_features->timestamps = 1;
+       supported_features->case_sensitive_filenames = 1;
+       return 0;
+}
+
+#define NUM_PATHBUFS 2  /* We need 2 when creating hard links  */
+
+struct unix_apply_ctx {
+       /* Extract flags, the pointer to the WIMStruct, etc.  */
+       struct apply_ctx common;
+
+       /* Buffers for building extraction paths (allocated).  */
+       char *pathbufs[NUM_PATHBUFS];
+
+       /* Index of next pathbuf to use  */
+       unsigned which_pathbuf;
+
+       /* Currently open file descriptors for extraction  */
+       struct filedes open_fds[MAX_OPEN_FILES];
+
+       /* Number of currently open file descriptors in open_fds, starting from
+        * the beginning of the array.  */
+       unsigned num_open_fds;
+
+       /* Buffer for reading reparse point data into memory  */
+       u8 reparse_data[REPARSE_DATA_MAX_SIZE];
+
+       /* Pointer to the next byte in @reparse_data to fill  */
+       u8 *reparse_ptr;
+
+       /* Absolute path to the target directory (allocated buffer).  Only set
+        * if needed for absolute symbolic link fixups.  */
+       char *target_abspath;
+
+       /* Number of characters in target_abspath.  */
+       size_t target_abspath_nchars;
+
+       /* Number of special files we couldn't create due to EPERM  */
+       unsigned long num_special_files_ignored;
+};
+
+/* Returns the number of characters needed to represent the path to the
+ * specified @dentry when extracted, not including the null terminator or the
+ * path to the target directory itself.  */
+static size_t
+unix_dentry_path_length(const struct wim_dentry *dentry)
+{
+       size_t len = 0;
+       const struct wim_dentry *d;
+
+       d = dentry;
+       do {
+               len += d->d_extraction_name_nchars + 1;
+               d = d->d_parent;
+       } while (!dentry_is_root(d) && will_extract_dentry(d));
+
+       return len;
+}
+
+/* Returns the maximum number of characters needed to represent the path to any
+ * dentry in @dentry_list when extracted, including the null terminator and the
+ * path to the target directory itself.  */
+static size_t
+unix_compute_path_max(const struct list_head *dentry_list,
+                     const struct unix_apply_ctx *ctx)
+{
+       size_t max = 0;
+       size_t len;
+       const struct wim_dentry *dentry;
+
+       list_for_each_entry(dentry, dentry_list, d_extraction_list_node) {
+               len = unix_dentry_path_length(dentry);
+               if (len > max)
+                       max = len;
        }
-       return num_components;
+
+       /* Account for target and null terminator.  */
+       return ctx->common.target_nchars + max + 1;
 }
 
+/* Builds and returns the filesystem path to which to extract @dentry.
+ * This cycles through NUM_PATHBUFS different buffers.  */
 static const char *
-path_next_part(const char *path)
+unix_build_extraction_path(const struct wim_dentry *dentry,
+                          struct unix_apply_ctx *ctx)
+{
+       char *pathbuf;
+       char *p;
+       const struct wim_dentry *d;
+
+       pathbuf = ctx->pathbufs[ctx->which_pathbuf];
+       ctx->which_pathbuf = (ctx->which_pathbuf + 1) % NUM_PATHBUFS;
+
+       p = &pathbuf[ctx->common.target_nchars +
+                    unix_dentry_path_length(dentry)];
+       *p = '\0';
+       d = dentry;
+       do {
+               p -= d->d_extraction_name_nchars;
+               memcpy(p, d->d_extraction_name, d->d_extraction_name_nchars);
+               *--p = '/';
+               d = d->d_parent;
+       } while (!dentry_is_root(d) && will_extract_dentry(d));
+
+       return pathbuf;
+}
+
+/* This causes the next call to unix_build_extraction_path() to use the same
+ * path buffer as the previous call.  */
+static void
+unix_reuse_pathbuf(struct unix_apply_ctx *ctx)
 {
-       while (*path && *path != '/')
-               path++;
-       while (*path && *path == '/')
-               path++;
-       return path;
+       ctx->which_pathbuf = (ctx->which_pathbuf - 1) % NUM_PATHBUFS;
 }
 
+/* Builds and returns the filesystem path to which to extract an unspecified
+ * alias of the @inode.  This cycles through NUM_PATHBUFS different buffers.  */
+static const char *
+unix_build_inode_extraction_path(const struct wim_inode *inode,
+                                struct unix_apply_ctx *ctx)
+{
+       return unix_build_extraction_path(inode_first_extraction_dentry(inode), ctx);
+}
+
+/* Should the specified file be extracted as a directory on UNIX?  We extract
+ * the file as a directory if FILE_ATTRIBUTE_DIRECTORY is set and the file does
+ * not have a symlink or junction reparse point.  It *may* have a different type
+ * of reparse point.  */
+static inline bool
+should_extract_as_directory(const struct wim_inode *inode)
+{
+       return (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY) &&
+               !inode_is_symlink(inode);
+}
+
+/* Sets the timestamps on a file being extracted.
+ *
+ * Either @fd or @path must be specified (not -1 and not NULL, respectively).
+ */
 static int
-unix_extract_regular_file_linked(struct wim_dentry *dentry,
-                                const char *output_path,
-                                struct apply_args *args,
-                                struct wim_lookup_table_entry *lte)
+unix_set_timestamps(int fd, const char *path, u64 atime, u64 mtime)
 {
-       /* This mode overrides the normal hard-link extraction and
-        * instead either symlinks or hardlinks *all* identical files in
-        * the WIM, even if they are in a different image (in the case
-        * of a multi-image extraction) */
-
-       if (args->extract_flags & WIMLIB_EXTRACT_FLAG_HARDLINK) {
-               if (link(lte->extracted_file, output_path) != 0) {
-                       ERROR_WITH_ERRNO("Failed to hard link "
-                                        "`%s' to `%s'",
-                                        output_path, lte->extracted_file);
-                       return WIMLIB_ERR_LINK;
-               }
-       } else {
-               int num_path_components;
-               int num_output_dir_path_components;
-               size_t extracted_file_len;
-               char *p;
-               const char *p2;
-               size_t i;
-               const struct wim_dentry *d;
-
-               num_path_components = 0;
-               for (d = dentry; d != args->extract_root; d = d->parent)
-                       num_path_components++;
-               wimlib_assert(num_path_components > 0);
-               num_path_components--;
-               num_output_dir_path_components = get_num_path_components(args->target);
-
-               if (args->extract_flags & WIMLIB_EXTRACT_FLAG_MULTI_IMAGE) {
-                       num_path_components++;
-                       num_output_dir_path_components--;
-               }
-               extracted_file_len = strlen(lte->extracted_file);
+       {
+               struct timespec times[2];
 
-               char buf[extracted_file_len + 3 * num_path_components + 1];
-               p = &buf[0];
+               times[0] = wim_timestamp_to_timespec(atime);
+               times[1] = wim_timestamp_to_timespec(mtime);
 
-               for (i = 0; i < num_path_components; i++) {
-                       *p++ = '.';
-                       *p++ = '.';
-                       *p++ = '/';
-               }
-               p2 = lte->extracted_file;
-               while (*p2 == '/')
-                       p2++;
-               while (num_output_dir_path_components > 0) {
-                       p2 = path_next_part(p2);
-                       num_output_dir_path_components--;
-               }
-               strcpy(p, p2);
-               if (symlink(buf, output_path) != 0) {
-                       ERROR_WITH_ERRNO("Failed to symlink `%s' to `%s'",
-                                        buf, lte->extracted_file);
-                       return WIMLIB_ERR_LINK;
-               }
+               errno = ENOSYS;
+#ifdef HAVE_FUTIMENS
+               if (fd >= 0 && !futimens(fd, times))
+                       return 0;
+#endif
+#ifdef HAVE_UTIMENSAT
+               if (fd < 0 && !utimensat(AT_FDCWD, path, times, AT_SYMLINK_NOFOLLOW))
+                       return 0;
+#endif
+               if (errno != ENOSYS)
+                       return WIMLIB_ERR_SET_TIMESTAMPS;
+       }
+       {
+               struct timeval times[2];
+
+               times[0] = wim_timestamp_to_timeval(atime);
+               times[1] = wim_timestamp_to_timeval(mtime);
+
+               if (fd >= 0 && !futimes(fd, times))
+                       return 0;
+               if (fd < 0 && !lutimes(path, times))
+                       return 0;
+               return WIMLIB_ERR_SET_TIMESTAMPS;
        }
-       return 0;
 }
 
 static int
-symlink_apply_unix_data(const char *link,
-                       const struct wimlib_unix_data *unix_data)
+unix_set_owner_and_group(int fd, const char *path, uid_t uid, gid_t gid)
 {
-       if (lchown(link, unix_data->uid, unix_data->gid)) {
-               if (errno == EPERM) {
-                       /* Ignore */
-                       WARNING_WITH_ERRNO("failed to set symlink UNIX "
-                                          "owner/group on \"%s\"", link);
-               } else {
-                       ERROR_WITH_ERRNO("failed to set symlink UNIX "
-                                        "owner/group on \"%s\"", link);
-                       return WIMLIB_ERR_INVALID_DENTRY;
-               }
-       }
-       return 0;
+       if (fd >= 0 && !fchown(fd, uid, gid))
+               return 0;
+       if (fd < 0 && !lchown(path, uid, gid))
+               return 0;
+       return WIMLIB_ERR_SET_SECURITY;
 }
 
 static int
-fd_apply_unix_data(int fd, const char *path,
-                  const struct wimlib_unix_data *unix_data,
-                  int extract_flags)
+unix_set_mode(int fd, const char *path, mode_t mode)
 {
-       if (extract_flags & WIMLIB_EXTRACT_FLAG_NO_ACLS)
+       if (fd >= 0 && !fchmod(fd, mode))
                return 0;
+       if (fd < 0 && !chmod(path, mode))
+               return 0;
+       return WIMLIB_ERR_SET_SECURITY;
+}
 
-       if (fchown(fd, unix_data->uid, unix_data->gid)) {
-               if (errno == EPERM &&
-                   !(extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS))
-               {
-                       WARNING_WITH_ERRNO("failed to set file UNIX "
-                                          "owner/group on \"%s\"", path);
-               } else {
-                       ERROR_WITH_ERRNO("failed to set file UNIX "
-                                        "owner/group on \"%s\"", path);
-                       return (errno == EPERM) ? WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT :
-                               WIMLIB_ERR_WRITE;
+/*
+ * Set metadata on an extracted file.
+ *
+ * @fd is an open file descriptor to the extracted file, or -1.  @path is the
+ * path to the extracted file, or NULL.  If valid, this function uses @fd.
+ * Otherwise, if valid, it uses @path.  Otherwise, it calculates the path to one
+ * alias of the extracted file and uses it.
+ */
+static int
+unix_set_metadata(int fd, const struct wim_inode *inode,
+                 const char *path, struct unix_apply_ctx *ctx)
+{
+       int ret;
+       struct wimlib_unix_data unix_data;
+
+       if (fd < 0 && !path)
+               path = unix_build_inode_extraction_path(inode, ctx);
+
+       if ((ctx->common.extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA)
+           && inode_get_unix_data(inode, &unix_data))
+       {
+               u32 uid = unix_data.uid;
+               u32 gid = unix_data.gid;
+               u32 mode = unix_data.mode;
+
+               ret = unix_set_owner_and_group(fd, path, uid, gid);
+               if (ret) {
+                       if (!path)
+                               path = unix_build_inode_extraction_path(inode, ctx);
+                       if (ctx->common.extract_flags &
+                           WIMLIB_EXTRACT_FLAG_STRICT_ACLS)
+                       {
+                               ERROR_WITH_ERRNO("Can't set uid=%"PRIu32" and "
+                                                "gid=%"PRIu32" on \"%s\"",
+                                                uid, gid, path);
+                               return ret;
+                       } else {
+                               WARNING_WITH_ERRNO("Can't set uid=%"PRIu32" and "
+                                                  "gid=%"PRIu32" on \"%s\"",
+                                                  uid, gid, path);
+                       }
+               }
+
+               ret = 0;
+               if (!inode_is_symlink(inode))
+                       ret = unix_set_mode(fd, path, mode);
+               if (ret) {
+                       if (!path)
+                               path = unix_build_inode_extraction_path(inode, ctx);
+                       if (ctx->common.extract_flags &
+                           WIMLIB_EXTRACT_FLAG_STRICT_ACLS)
+                       {
+                               ERROR_WITH_ERRNO("Can't set mode=0%"PRIo32" "
+                                                "on \"%s\"", mode, path);
+                               return ret;
+                       } else {
+                               WARNING_WITH_ERRNO("Can't set mode=0%"PRIo32" "
+                                                  "on \"%s\"", mode, path);
+                       }
                }
        }
 
-       if (fchmod(fd, unix_data->mode)) {
-               if (errno == EPERM &&
-                   !(extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS))
+       ret = unix_set_timestamps(fd, path,
+                                 inode->i_last_access_time,
+                                 inode->i_last_write_time);
+       if (ret) {
+               if (!path)
+                       path = unix_build_inode_extraction_path(inode, ctx);
+               if (ctx->common.extract_flags &
+                   WIMLIB_EXTRACT_FLAG_STRICT_TIMESTAMPS)
                {
-                       WARNING_WITH_ERRNO("failed to set UNIX file mode "
-                                          "on \"%s\"", path);
+                       ERROR_WITH_ERRNO("Can't set timestamps on \"%s\"", path);
+                       return ret;
                } else {
-                       ERROR_WITH_ERRNO("failed to set UNIX file mode "
-                                        "on \"%s\"", path);
-                       return (errno == EPERM) ? WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT :
-                               WIMLIB_ERR_WRITE;
+                       WARNING_WITH_ERRNO("Can't set timestamps on \"%s\"", path);
                }
        }
        return 0;
 }
 
+/* Extract all needed aliases of the @inode, where one alias, corresponding to
+ * @first_dentry, has already been extracted to @first_path.  */
 static int
-dir_apply_unix_data(const char *dir, const struct wimlib_unix_data *unix_data,
-                   int extract_flags)
+unix_create_hardlinks(const struct wim_inode *inode,
+                     const struct wim_dentry *first_dentry,
+                     const char *first_path, struct unix_apply_ctx *ctx)
 {
-       int dfd = open(dir, O_RDONLY);
-       int ret;
-       if (dfd >= 0) {
-               ret = fd_apply_unix_data(dfd, dir, unix_data, extract_flags);
-               if (close(dfd) && ret == 0) {
-                       ERROR_WITH_ERRNO("can't close directory `%s'", dir);
-                       ret = WIMLIB_ERR_WRITE;
+       const struct wim_dentry *dentry;
+       const char *newpath;
+
+       inode_for_each_extraction_alias(dentry, inode) {
+               if (dentry == first_dentry)
+                       continue;
+
+               newpath = unix_build_extraction_path(dentry, ctx);
+       retry_link:
+               if (link(first_path, newpath)) {
+                       if (errno == EEXIST && !unlink(newpath))
+                               goto retry_link;
+                       ERROR_WITH_ERRNO("Can't create hard link "
+                                        "\"%s\" => \"%s\"", newpath, first_path);
+                       return WIMLIB_ERR_LINK;
                }
-       } else {
-               ERROR_WITH_ERRNO("can't open directory `%s'", dir);
-               ret = WIMLIB_ERR_OPENDIR;
+               unix_reuse_pathbuf(ctx);
        }
-       return ret;
+       return 0;
 }
 
+/* If @dentry represents a directory, create it.  */
 static int
-unix_extract_regular_file_unlinked(struct wim_dentry *dentry,
-                                  struct apply_args *args,
-                                  const char *output_path,
-                                  struct wim_lookup_table_entry *lte)
+unix_create_if_directory(const struct wim_dentry *dentry,
+                        struct unix_apply_ctx *ctx)
 {
-       /* Normal mode of extraction.  Regular files and hard links are
-        * extracted in the way that they appear in the WIM. */
+       const char *path;
+       struct stat stbuf;
+
+       if (!should_extract_as_directory(dentry->d_inode))
+               return 0;
+
+       path = unix_build_extraction_path(dentry, ctx);
+       if (mkdir(path, 0755) &&
+           /* It's okay if the path already exists, as long as it's a
+            * directory.  */
+           !(errno == EEXIST && !lstat(path, &stbuf) && S_ISDIR(stbuf.st_mode)))
+       {
+               ERROR_WITH_ERRNO("Can't create directory \"%s\"", path);
+               return WIMLIB_ERR_MKDIR;
+       }
+
+       return report_file_created(&ctx->common);
+}
 
-       int out_fd;
+/* If @dentry represents an empty regular file or a special file, create it, set
+ * its metadata, and create any needed hard links.  */
+static int
+unix_extract_if_empty_file(const struct wim_dentry *dentry,
+                          struct unix_apply_ctx *ctx)
+{
+       const struct wim_inode *inode;
+       struct wimlib_unix_data unix_data;
+       const char *path;
        int ret;
-       struct wim_inode *inode = dentry->d_inode;
 
-       if (!((args->extract_flags & WIMLIB_EXTRACT_FLAG_MULTI_IMAGE)
-               && (args->extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
-                                    WIMLIB_EXTRACT_FLAG_HARDLINK))))
+       inode = dentry->d_inode;
+
+       /* Extract all aliases only when the "first" comes up.  */
+       if (dentry != inode_first_extraction_dentry(inode))
+               return 0;
+
+       /* Is this a directory, a symbolic link, or any type of nonempty file?
+        */
+       if (should_extract_as_directory(inode) || inode_is_symlink(inode) ||
+           inode_get_blob_for_unnamed_data_stream_resolved(inode))
+               return 0;
+
+       /* Recognize special files in UNIX_DATA mode  */
+       if ((ctx->common.extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) &&
+           inode_get_unix_data(inode, &unix_data) &&
+           !S_ISREG(unix_data.mode))
        {
-               /* If the dentry is part of a hard link set of at least 2
-                * dentries and 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 inode->i_extracted_file field so that other dentries
-                * in the hard link group can link to it. */
-               if (inode->i_nlink > 1) {
-                       if (inode->i_extracted_file) {
-                               DEBUG("Extracting hard link `%s' => `%s'",
-                                     output_path, inode->i_extracted_file);
-                               if (link(inode->i_extracted_file, output_path) != 0) {
-                                       ERROR_WITH_ERRNO("Failed to hard link "
-                                                        "`%s' to `%s'",
-                                                        output_path,
-                                                        inode->i_extracted_file);
-                                       return WIMLIB_ERR_LINK;
-                               }
+               path = unix_build_extraction_path(dentry, ctx);
+       retry_mknod:
+               if (mknod(path, unix_data.mode, unix_data.rdev)) {
+                       if (errno == EPERM) {
+                               WARNING_WITH_ERRNO("Can't create special "
+                                                  "file \"%s\"", path);
+                               ctx->num_special_files_ignored++;
                                return 0;
                        }
-                       FREE(inode->i_extracted_file);
-                       inode->i_extracted_file = STRDUP(output_path);
-                       if (!inode->i_extracted_file) {
-                               ERROR("Failed to allocate memory for filename");
-                               return WIMLIB_ERR_NOMEM;
-                       }
+                       if (errno == EEXIST && !unlink(path))
+                               goto retry_mknod;
+                       ERROR_WITH_ERRNO("Can't create special file \"%s\"",
+                                        path);
+                       return WIMLIB_ERR_MKNOD;
+               }
+               /* On special files, we can set timestamps immediately because
+                * we don't need to write any data to them.  */
+               ret = unix_set_metadata(-1, inode, path, ctx);
+       } else {
+               int fd;
+
+               path = unix_build_extraction_path(dentry, ctx);
+       retry_create:
+               fd = open(path, O_TRUNC | O_CREAT | O_WRONLY | O_NOFOLLOW, 0644);
+               if (fd < 0) {
+                       if (errno == EEXIST && !unlink(path))
+                               goto retry_create;
+                       ERROR_WITH_ERRNO("Can't create regular file \"%s\"", path);
+                       return WIMLIB_ERR_OPEN;
+               }
+               /* On empty files, we can set timestamps immediately because we
+                * don't need to write any data to them.  */
+               ret = unix_set_metadata(fd, inode, path, ctx);
+               if (close(fd) && !ret) {
+                       ERROR_WITH_ERRNO("Error closing \"%s\"", path);
+                       ret = WIMLIB_ERR_WRITE;
                }
        }
+       if (ret)
+               return ret;
 
-       /* Extract the contents of the file to @output_path. */
+       ret = unix_create_hardlinks(inode, dentry, path, ctx);
+       if (ret)
+               return ret;
 
-       out_fd = open(output_path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
-       if (out_fd == -1) {
-               ERROR_WITH_ERRNO("Failed to open the file `%s' for writing",
-                                output_path);
-               return WIMLIB_ERR_OPEN;
-       }
+       return report_file_created(&ctx->common);
+}
 
-       if (!lte) {
-               /* Empty file with no lookup table entry */
-               DEBUG("Empty file `%s'.", output_path);
-               ret = 0;
-               goto out_extract_unix_data;
-       }
+static int
+unix_create_dirs_and_empty_files(const struct list_head *dentry_list,
+                                struct unix_apply_ctx *ctx)
+{
+       const struct wim_dentry *dentry;
+       int ret;
 
-       ret = extract_wim_resource_to_fd(lte, out_fd, wim_resource_size(lte));
-       if (ret) {
-               ERROR("Failed to extract resource to `%s'", output_path);
-               goto out;
+       list_for_each_entry(dentry, dentry_list, d_extraction_list_node) {
+               ret = unix_create_if_directory(dentry, ctx);
+               if (ret)
+                       return ret;
        }
-
-out_extract_unix_data:
-       if (args->extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) {
-               struct wimlib_unix_data unix_data;
-               ret = inode_get_unix_data(inode, &unix_data, NULL);
-               if (ret > 0)
-                       ;
-               else if (ret < 0)
-                       ret = 0;
-               else
-                       ret = fd_apply_unix_data(out_fd, output_path, &unix_data,
-                                                args->extract_flags);
+       list_for_each_entry(dentry, dentry_list, d_extraction_list_node) {
+               ret = unix_extract_if_empty_file(dentry, ctx);
                if (ret)
-                       goto out;
+                       return ret;
        }
-       if (lte)
-               args->progress.extract.completed_bytes += wim_resource_size(lte);
-out:
-       if (close(out_fd) != 0) {
-               ERROR_WITH_ERRNO("Failed to close file `%s'", output_path);
-               if (ret == 0)
-                       ret = WIMLIB_ERR_WRITE;
+       return 0;
+}
+
+static void
+unix_count_dentries(const struct list_head *dentry_list,
+                   u64 *dir_count_ret, u64 *empty_file_count_ret)
+{
+       const struct wim_dentry *dentry;
+       u64 dir_count = 0;
+       u64 empty_file_count = 0;
+
+       list_for_each_entry(dentry, dentry_list, d_extraction_list_node) {
+
+               const struct wim_inode *inode = dentry->d_inode;
+
+               if (should_extract_as_directory(inode))
+                       dir_count++;
+               else if ((dentry == inode_first_extraction_dentry(inode)) &&
+                        !inode_is_symlink(inode) &&
+                        !inode_get_blob_for_unnamed_data_stream_resolved(inode))
+                       empty_file_count++;
        }
-       return ret;
+
+       *dir_count_ret = dir_count;
+       *empty_file_count_ret = empty_file_count;
 }
 
 static int
-unix_extract_regular_file(struct wim_dentry *dentry,
-                         struct apply_args *args,
-                         const char *output_path)
+unix_create_symlink(const struct wim_inode *inode, const char *path,
+                   size_t rpdatalen, struct unix_apply_ctx *ctx)
 {
-       struct wim_lookup_table_entry *lte;
-       const struct wim_inode *inode = dentry->d_inode;
+       char target[REPARSE_POINT_MAX_SIZE];
+       struct blob_descriptor blob_override;
+       int ret;
 
-       lte = inode_unnamed_lte_resolved(inode);
+       blob_set_is_located_in_attached_buffer(&blob_override,
+                                              ctx->reparse_data, rpdatalen);
 
-       if (lte && (args->extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
-                                          WIMLIB_EXTRACT_FLAG_HARDLINK)))
-       {
-               if (lte->extracted_file) {
-                       return unix_extract_regular_file_linked(dentry,
-                                                               output_path,
-                                                               args, lte);
-               } else {
-                       lte->extracted_file = STRDUP(output_path);
-                       if (!lte->extracted_file)
-                               return WIMLIB_ERR_NOMEM;
-               }
+       ret = wim_inode_readlink(inode, target, sizeof(target) - 1,
+                                &blob_override,
+                                ctx->target_abspath,
+                                ctx->target_abspath_nchars);
+       if (unlikely(ret < 0)) {
+               errno = -ret;
+               return WIMLIB_ERR_READLINK;
        }
-       return unix_extract_regular_file_unlinked(dentry, args, output_path, lte);
+       target[ret] = '\0';
+
+retry_symlink:
+       if (symlink(target, path)) {
+               if (errno == EEXIST && !unlink(path))
+                       goto retry_symlink;
+               return WIMLIB_ERR_LINK;
+       }
+       return 0;
+}
+
+static void
+unix_cleanup_open_fds(struct unix_apply_ctx *ctx, unsigned offset)
+{
+       for (unsigned i = offset; i < ctx->num_open_fds; i++)
+               filedes_close(&ctx->open_fds[i]);
+       ctx->num_open_fds = 0;
 }
 
 static int
-unix_extract_symlink(struct wim_dentry *dentry,
-                    struct apply_args *args,
-                    const char *output_path)
+unix_begin_extract_blob_instance(const struct blob_descriptor *blob,
+                                const struct wim_inode *inode,
+                                const struct wim_inode_stream *strm,
+                                struct unix_apply_ctx *ctx)
 {
-       char target[4096 + args->target_realpath_len];
-       char *fixed_target;
-       const struct wim_inode *inode = dentry->d_inode;
-
-       ssize_t ret = wim_inode_readlink(inode,
-                                        target + args->target_realpath_len,
-                                        sizeof(target) - args->target_realpath_len - 1);
-       struct wim_lookup_table_entry *lte;
-
-       if (ret <= 0) {
-               ERROR("Could not read the symbolic link from dentry `%s'",
-                     dentry_full_path(dentry));
-               return WIMLIB_ERR_INVALID_DENTRY;
-       }
-       target[args->target_realpath_len + ret] = '\0';
-       if (target[args->target_realpath_len] == '/' &&
-           args->extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX)
-       {
-               /* Fix absolute symbolic link target to point into the actual
-                * extraction destination */
-               memcpy(target, args->target_realpath,
-                      args->target_realpath_len);
-               fixed_target = target;
-       } else {
-               /* Keep same link target */
-               fixed_target = target + args->target_realpath_len;
+       const struct wim_dentry *first_dentry;
+       const char *first_path;
+       int fd;
+
+       if (unlikely(strm->stream_type == STREAM_TYPE_REPARSE_POINT)) {
+               /* On UNIX, symbolic links must be created with symlink(), which
+                * requires that the full link target be available.  */
+               if (blob->size > REPARSE_DATA_MAX_SIZE) {
+                       ERROR_WITH_ERRNO("Reparse data of \"%s\" has size "
+                                        "%"PRIu64" bytes (exceeds %u bytes)",
+                                        inode_any_full_path(inode),
+                                        blob->size, REPARSE_DATA_MAX_SIZE);
+                       return WIMLIB_ERR_INVALID_REPARSE_DATA;
+               }
+               ctx->reparse_ptr = ctx->reparse_data;
+               return 0;
        }
-       ret = symlink(fixed_target, output_path);
-       if (ret) {
-               ERROR_WITH_ERRNO("Failed to symlink `%s' to `%s'",
-                                output_path, fixed_target);
-               return WIMLIB_ERR_LINK;
+
+       wimlib_assert(stream_is_unnamed_data_stream(strm));
+
+       /* Unnamed data stream of "regular" file  */
+
+       /* This should be ensured by extract_blob_list()  */
+       wimlib_assert(ctx->num_open_fds < MAX_OPEN_FILES);
+
+       first_dentry = inode_first_extraction_dentry(inode);
+       first_path = unix_build_extraction_path(first_dentry, ctx);
+retry_create:
+       fd = open(first_path, O_TRUNC | O_CREAT | O_WRONLY | O_NOFOLLOW, 0644);
+       if (fd < 0) {
+               if (errno == EEXIST && !unlink(first_path))
+                       goto retry_create;
+               ERROR_WITH_ERRNO("Can't create regular file \"%s\"", first_path);
+               return WIMLIB_ERR_OPEN;
        }
-       if (args->extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) {
-               struct wimlib_unix_data unix_data;
-               ret = inode_get_unix_data(inode, &unix_data, NULL);
-               if (ret > 0)
-                       ;
-               else if (ret < 0)
-                       ret = 0;
-               else
-                       ret = symlink_apply_unix_data(output_path, &unix_data);
-               if (ret)
+       filedes_init(&ctx->open_fds[ctx->num_open_fds++], fd);
+       return unix_create_hardlinks(inode, first_dentry, first_path, ctx);
+}
+
+/* Called when starting to read a blob for extraction  */
+static int
+unix_begin_extract_blob(struct blob_descriptor *blob, void *_ctx)
+{
+       struct unix_apply_ctx *ctx = _ctx;
+       const struct blob_extraction_target *targets = blob_extraction_targets(blob);
+
+       for (u32 i = 0; i < blob->out_refcnt; i++) {
+               int ret = unix_begin_extract_blob_instance(blob,
+                                                          targets[i].inode,
+                                                          targets[i].stream,
+                                                          ctx);
+               if (ret) {
+                       ctx->reparse_ptr = NULL;
+                       unix_cleanup_open_fds(ctx, 0);
                        return ret;
+               }
        }
-       lte = inode_unnamed_lte_resolved(inode);
-       wimlib_assert(lte != NULL);
-       args->progress.extract.completed_bytes += wim_resource_size(lte);
        return 0;
 }
 
+/* Called when the next chunk of a blob has been read for extraction  */
 static int
-unix_extract_directory(struct wim_dentry *dentry, const char *output_path,
-                      int extract_flags)
+unix_extract_chunk(const void *chunk, size_t size, void *_ctx)
 {
+       struct unix_apply_ctx *ctx = _ctx;
        int ret;
-       struct stat stbuf;
 
-       ret = stat(output_path, &stbuf);
-       if (ret == 0) {
-               if (S_ISDIR(stbuf.st_mode)) {
-                       goto dir_exists;
-               } else {
-                       ERROR("\"%s\" is not a directory", output_path);
-                       return WIMLIB_ERR_MKDIR;
-               }
-       } else {
-               if (errno != ENOENT) {
-                       ERROR_WITH_ERRNO("Failed to stat \"%s\"", output_path);
-                       return WIMLIB_ERR_STAT;
+       for (unsigned i = 0; i < ctx->num_open_fds; i++) {
+               ret = full_write(&ctx->open_fds[i], chunk, size);
+               if (ret) {
+                       ERROR_WITH_ERRNO("Error writing data to filesystem");
+                       return ret;
                }
        }
+       if (ctx->reparse_ptr)
+               ctx->reparse_ptr = mempcpy(ctx->reparse_ptr, chunk, size);
+       return 0;
+}
 
-       if (mkdir(output_path, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH)) {
-               ERROR_WITH_ERRNO("Cannot create directory \"%s\"", output_path);
-               return WIMLIB_ERR_MKDIR;
+/* Called when a blob has been fully read for extraction  */
+static int
+unix_end_extract_blob(struct blob_descriptor *blob, int status, void *_ctx)
+{
+       struct unix_apply_ctx *ctx = _ctx;
+       int ret;
+       unsigned j;
+       const struct blob_extraction_target *targets = blob_extraction_targets(blob);
+
+       ctx->reparse_ptr = NULL;
+
+       if (status) {
+               unix_cleanup_open_fds(ctx, 0);
+               return status;
        }
-dir_exists:
+
+       j = 0;
        ret = 0;
-       if (extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) {
-               struct wimlib_unix_data unix_data;
-               ret = inode_get_unix_data(dentry->d_inode, &unix_data, NULL);
-               if (ret > 0)
-                       ;
-               else if (ret < 0)
-                       ret = 0;
-               else
-                       ret = dir_apply_unix_data(output_path, &unix_data,
-                                                 extract_flags);
+       for (u32 i = 0; i < blob->out_refcnt; i++) {
+               struct wim_inode *inode = targets[i].inode;
+
+               if (inode_is_symlink(inode)) {
+                       /* We finally have the symlink data, so we can create
+                        * the symlink.  */
+                       const char *path;
+
+                       path = unix_build_inode_extraction_path(inode, ctx);
+                       ret = unix_create_symlink(inode, path, blob->size, ctx);
+                       if (ret) {
+                               ERROR_WITH_ERRNO("Can't create symbolic link "
+                                                "\"%s\"", path);
+                               break;
+                       }
+                       ret = unix_set_metadata(-1, inode, path, ctx);
+                       if (ret)
+                               break;
+               } else {
+                       /* Set metadata on regular file just before closing it.
+                        */
+                       struct filedes *fd = &ctx->open_fds[j];
+
+                       ret = unix_set_metadata(fd->fd, inode, NULL, ctx);
+                       if (ret)
+                               break;
+
+                       if (filedes_close(fd)) {
+                               ERROR_WITH_ERRNO("Error closing \"%s\"",
+                                                unix_build_inode_extraction_path(inode, ctx));
+                               ret = WIMLIB_ERR_WRITE;
+                               break;
+                       }
+                       j++;
+               }
        }
+       unix_cleanup_open_fds(ctx, j);
        return ret;
 }
 
-int
-unix_do_apply_dentry(const char *output_path, size_t output_path_len,
-                    struct wim_dentry *dentry, struct apply_args *args)
+static int
+unix_set_dir_metadata(struct list_head *dentry_list, struct unix_apply_ctx *ctx)
 {
-       const struct wim_inode *inode = dentry->d_inode;
-
-       if (inode_is_symlink(inode))
-               return unix_extract_symlink(dentry, args, output_path);
-       else if (inode_is_directory(inode))
-               return unix_extract_directory(dentry, output_path, args->extract_flags);
-       else
-               return unix_extract_regular_file(dentry, args, output_path);
+       const struct wim_dentry *dentry;
+       int ret;
+
+       list_for_each_entry_reverse(dentry, dentry_list, d_extraction_list_node) {
+               if (should_extract_as_directory(dentry->d_inode)) {
+                       ret = unix_set_metadata(-1, dentry->d_inode, NULL, ctx);
+                       if (ret)
+                               return ret;
+                       ret = report_file_metadata_applied(&ctx->common);
+                       if (ret)
+                               return ret;
+               }
+       }
+       return 0;
 }
 
-int
-unix_do_apply_dentry_timestamps(const char *output_path,
-                               size_t output_path_len,
-                               struct wim_dentry *dentry,
-                               struct apply_args *args)
+static int
+unix_extract(struct list_head *dentry_list, struct apply_ctx *_ctx)
 {
        int ret;
-       const struct wim_inode *inode = dentry->d_inode;
+       struct unix_apply_ctx *ctx = (struct unix_apply_ctx *)_ctx;
+       size_t path_max;
+       u64 dir_count;
+       u64 empty_file_count;
+
+       /* Compute the maximum path length that will be needed, then allocate
+        * some path buffers.  */
+       path_max = unix_compute_path_max(dentry_list, ctx);
+
+       for (unsigned i = 0; i < NUM_PATHBUFS; i++) {
+               ctx->pathbufs[i] = MALLOC(path_max);
+               if (!ctx->pathbufs[i]) {
+                       ret = WIMLIB_ERR_NOMEM;
+                       goto out;
+               }
+               /* Pre-fill the target in each path buffer.  We'll just append
+                * the rest of the paths after this.  */
+               memcpy(ctx->pathbufs[i],
+                      ctx->common.target, ctx->common.target_nchars);
+       }
 
-#ifdef HAVE_UTIMENSAT
-       /* Convert the WIM timestamps, which are accurate to 100 nanoseconds,
-        * into `struct timespec's for passing to utimensat(), which is accurate
-        * to 1 nanosecond. */
-
-       struct timespec ts[2];
-       ts[0] = wim_timestamp_to_timespec(inode->i_last_access_time);
-       ts[1] = wim_timestamp_to_timespec(inode->i_last_write_time);
-       ret = utimensat(AT_FDCWD, output_path, ts, AT_SYMLINK_NOFOLLOW);
+       /* Extract directories and empty regular files.  Directories are needed
+        * because we can't extract any other files until their directories
+        * exist.  Empty files are needed because they don't have
+        * representatives in the blob list.  */
+
+       unix_count_dentries(dentry_list, &dir_count, &empty_file_count);
+
+       ret = start_file_structure_phase(&ctx->common, dir_count + empty_file_count);
        if (ret)
-               ret = errno;
-#else
-       ret = ENOSYS;
-#endif
+               goto out;
 
-       if (ret == ENOSYS) {
-               /* utimensat() not implemented or not available */
-       #ifdef HAVE_LUTIMES
-               /* Convert the WIM timestamps, which are accurate to 100
-                * nanoseconds, into `struct timeval's for passing to lutimes(),
-                * which is accurate to 1 microsecond. */
-               struct timeval tv[2];
-               tv[0] = wim_timestamp_to_timeval(inode->i_last_access_time);
-               tv[1] = wim_timestamp_to_timeval(inode->i_last_write_time);
-               ret = lutimes(output_path, tv);
-               if (ret)
-                       ret = errno;
-       #endif
-       }
+       ret = unix_create_dirs_and_empty_files(dentry_list, ctx);
+       if (ret)
+               goto out;
+
+       ret = end_file_structure_phase(&ctx->common);
+       if (ret)
+               goto out;
 
-       if (ret == ENOSYS) {
-               /* utimensat() and lutimes() both not implemented or not
-                * available */
-       #ifdef HAVE_UTIME
-               /* Convert the WIM timestamps, which are accurate to 100
-                * nanoseconds, into a `struct utimbuf's for passing to
-                * utime(), which is accurate to 1 second. */
-               struct utimbuf buf;
-               buf.actime = wim_timestamp_to_unix(inode->i_last_access_time);
-               buf.modtime = wim_timestamp_to_unix(inode->i_last_write_time);
-               ret = utime(output_path, &buf);
-       #endif
+       /* Get full path to target if needed for absolute symlink fixups.  */
+       if ((ctx->common.extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX) &&
+           ctx->common.required_features.symlink_reparse_points)
+       {
+               ctx->target_abspath = realpath(ctx->common.target, NULL);
+               if (!ctx->target_abspath) {
+                       ret = WIMLIB_ERR_NOMEM;
+                       goto out;
+               }
+               ctx->target_abspath_nchars = strlen(ctx->target_abspath);
        }
-       if (ret && args->num_utime_warnings < 10) {
-               WARNING_WITH_ERRNO("Failed to set timestamp on file `%s'",
-                                   output_path);
-               args->num_utime_warnings++;
+
+       /* Extract nonempty regular files and symbolic links.  */
+
+       struct read_blob_callbacks cbs = {
+               .begin_blob     = unix_begin_extract_blob,
+               .consume_chunk  = unix_extract_chunk,
+               .end_blob       = unix_end_extract_blob,
+               .ctx            = ctx,
+       };
+       ret = extract_blob_list(&ctx->common, &cbs);
+       if (ret)
+               goto out;
+
+
+       /* Set directory metadata.  We do this last so that we get the right
+        * directory timestamps.  */
+       ret = start_file_metadata_phase(&ctx->common, dir_count);
+       if (ret)
+               goto out;
+
+       ret = unix_set_dir_metadata(dentry_list, ctx);
+       if (ret)
+               goto out;
+
+       ret = end_file_metadata_phase(&ctx->common);
+       if (ret)
+               goto out;
+
+       if (ctx->num_special_files_ignored) {
+               WARNING("%lu special files were not extracted due to EPERM!",
+                       ctx->num_special_files_ignored);
        }
-       return 0;
+out:
+       for (unsigned i = 0; i < NUM_PATHBUFS; i++)
+               FREE(ctx->pathbufs[i]);
+       FREE(ctx->target_abspath);
+       return ret;
 }
 
-#endif /* !__WIN32__ */
+const struct apply_operations unix_apply_ops = {
+       .name                   = "UNIX",
+       .get_supported_features = unix_get_supported_features,
+       .extract                = unix_extract,
+       .context_size           = sizeof(struct unix_apply_ctx),
+};