Refactor some of the dentry, inode, and lookup table code
[wimlib] / src / unix_apply.c
index 97c1c83..21a804a 100644 (file)
-#include "config.h"
+/*
+ * unix_apply.c - Code to apply files from a WIM image on UNIX.
+ */
+
+/*
+ * Copyright (C) 2012, 2013 Eric Biggers
+ *
+ * This file is part of wimlib, a library for working with WIM files.
+ *
+ * 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
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with wimlib; if not, see http://www.gnu.org/licenses/.
+ */
 
-#ifdef HAVE_UTIME_H
-#  include <utime.h>
+#ifndef __WIN32__
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
 #endif
-#include <dirent.h>
+
+#include "wimlib/apply.h"
+#include "wimlib/error.h"
+#include "wimlib/resource.h"
+#include "wimlib/timestamp.h"
+#include "wimlib/unix_data.h"
+
 #include <errno.h>
 #include <fcntl.h>
-#include <string.h>
+#include <limits.h>
 #include <sys/stat.h>
-#include <sys/time.h>
+#include <sys/types.h>
 #include <unistd.h>
 
-#include "timestamp.h"
-#include "wimlib_internal.h"
-#include "lookup_table.h"
+#ifdef HAVE_UTIME_H
+#  include <utime.h>
+#endif
 
-/* Returns the number of components of @path.  */
-static unsigned
-get_num_path_components(const char *path)
+static int
+unix_start_extract(const char *target, struct apply_ctx *ctx)
 {
-       unsigned num_components = 0;
-       while (*path) {
-               while (*path == '/')
-                       path++;
-               if (*path)
-                       num_components++;
-               while (*path && *path != '/')
-                       path++;
-       }
-       return num_components;
+       ctx->supported_features.hard_links = 1;
+       ctx->supported_features.symlink_reparse_points = 1;
+       ctx->supported_features.unix_data = 1;
+       return 0;
 }
 
-static const char *
-path_next_part(const char *path)
+static int
+unix_create_file(const char *path, struct apply_ctx *ctx, u64 *cookie_ret)
 {
-       while (*path && *path != '/')
-               path++;
-       while (*path && *path == '/')
-               path++;
-       return path;
+       int fd = open(path, O_TRUNC | O_CREAT | O_WRONLY, 0644);
+       if (fd < 0)
+               return WIMLIB_ERR_OPEN;
+       close(fd);
+       return 0;
 }
 
 static int
-extract_regular_file_linked(struct wim_dentry *dentry,
-                           const char *output_path,
-                           struct apply_args *args,
-                           struct wim_lookup_table_entry *lte)
+unix_create_directory(const tchar *path, struct apply_ctx *ctx, u64 *cookie_ret)
 {
-       /* 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;
-
-               num_path_components = get_num_path_components(dentry->_full_path) - 1;
-               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);
-
-               char buf[extracted_file_len + 3 * num_path_components + 1];
-               p = &buf[0];
+       struct stat stbuf;
 
-               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;
-               }
+       if (mkdir(path, 0755)) {
+               if (errno != EEXIST)
+                       return WIMLIB_ERR_MKDIR;
+               if (lstat(path, &stbuf))
+                       return WIMLIB_ERR_MKDIR;
+               errno = EEXIST;
+               if (!S_ISDIR(stbuf.st_mode))
+                       return WIMLIB_ERR_MKDIR;
        }
        return 0;
 }
 
 static int
-symlink_apply_unix_data(const char *link,
-                       const struct wimlib_unix_data *unix_data)
+unix_makelink(const tchar *oldpath, const tchar *newpath,
+             int (*makelink)(const tchar *oldpath, const tchar *newpath))
 {
-       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;
-               }
+       if ((*makelink)(oldpath, newpath)) {
+               if (errno != EEXIST)
+                       return WIMLIB_ERR_LINK;
+               if (unlink(newpath))
+                       return WIMLIB_ERR_LINK;
+               if ((*makelink)(oldpath, newpath))
+                       return WIMLIB_ERR_LINK;
        }
        return 0;
 }
-
 static int
-fd_apply_unix_data(int fd, const char *path,
-                  const struct wimlib_unix_data *unix_data,
-                  int extract_flags)
+unix_create_hardlink(const tchar *oldpath, const tchar *newpath,
+                    struct apply_ctx *ctx)
 {
-       if (extract_flags & WIMLIB_EXTRACT_FLAG_NO_ACLS)
-               return 0;
-
-       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;
-               }
-       }
-
-       if (fchmod(fd, unix_data->mode)) {
-               if (errno == EPERM &&
-                   !(extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS))
-               {
-                       WARNING_WITH_ERRNO("failed to set UNIX file mode "
-                                          "on \"%s\"", path);
-               } 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;
-               }
-       }
-       return 0;
+       return unix_makelink(oldpath, newpath, link);
 }
 
 static int
-dir_apply_unix_data(const char *dir, const struct wimlib_unix_data *unix_data,
-                   int extract_flags)
+unix_create_symlink(const tchar *oldpath, const tchar *newpath,
+                   struct 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;
-               }
-       } else {
-               ERROR_WITH_ERRNO("can't open directory `%s'", dir);
-               ret = WIMLIB_ERR_OPENDIR;
-       }
-       return ret;
+       return unix_makelink(oldpath, newpath, symlink);
 }
 
 static int
-extract_regular_file_unlinked(struct wim_dentry *dentry,
-                             struct apply_args *args,
-                             const char *output_path,
-                             struct wim_lookup_table_entry *lte)
+unix_extract_unnamed_stream(file_spec_t file,
+                           struct wim_lookup_table_entry *lte,
+                           struct apply_ctx *ctx)
 {
-       /* Normal mode of extraction.  Regular files and hard links are
-        * extracted in the way that they appear in the WIM. */
-
-       int out_fd;
+       const char *path = file.path;
+       struct filedes fd;
+       int raw_fd;
        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))))
-       {
-               /* 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;
-                               }
-                               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;
-                       }
-               }
-       }
 
-       /* Extract the contents of the file to @output_path. */
-
-       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);
+       raw_fd = open(path, O_WRONLY | O_TRUNC);
+       if (raw_fd < 0)
                return WIMLIB_ERR_OPEN;
-       }
-
-       if (!lte) {
-               /* Empty file with no lookup table entry */
-               DEBUG("Empty file `%s'.", output_path);
-               ret = 0;
-               goto out_extract_unix_data;
-       }
-
-       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;
-       }
-
-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);
-               if (ret)
-                       goto out;
-       }
-       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;
-       }
+       filedes_init(&fd, raw_fd);
+       ret = extract_full_stream_to_fd(lte, &fd);
+       if (filedes_close(&fd) && !ret)
+               ret = WIMLIB_ERR_WRITE;
        return ret;
 }
 
 static int
-extract_regular_file(struct wim_dentry *dentry,
-                    struct apply_args *args,
-                    const char *output_path)
-{
-       struct wim_lookup_table_entry *lte;
-       const struct wim_inode *inode = dentry->d_inode;
-
-       lte = inode_unnamed_lte_resolved(inode);
-
-       if (lte && (args->extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
-                                          WIMLIB_EXTRACT_FLAG_HARDLINK)))
-       {
-               if (lte->extracted_file) {
-                       return extract_regular_file_linked(dentry, output_path, args, lte);
-               } else {
-                       lte->extracted_file = STRDUP(output_path);
-                       if (!lte->extracted_file)
-                               return WIMLIB_ERR_NOMEM;
-               }
-       }
-       return extract_regular_file_unlinked(dentry, args, output_path, lte);
-}
-
-static int
-extract_symlink(struct wim_dentry *dentry,
-               struct apply_args *args,
-               const char *output_path)
+unix_set_unix_data(const tchar *path, const struct wimlib_unix_data *data,
+                  struct 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;
+       struct stat stbuf;
 
-       if (ret <= 0) {
-               ERROR("Could not read the symbolic link from dentry `%s'",
-                     dentry->_full_path);
-               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;
-       }
-       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;
-       }
-       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)
-                       return ret;
-       }
-       lte = inode_unnamed_lte_resolved(inode);
-       wimlib_assert(lte != NULL);
-       args->progress.extract.completed_bytes += wim_resource_size(lte);
+       if (lstat(path, &stbuf))
+               return WIMLIB_ERR_SET_SECURITY;
+       if (!S_ISLNK(stbuf.st_mode))
+               if (chmod(path, data->mode))
+                       return WIMLIB_ERR_SET_SECURITY;
+       if (lchown(path, data->uid, data->gid))
+               return WIMLIB_ERR_SET_SECURITY;
        return 0;
 }
 
 static int
-extract_directory(struct wim_dentry *dentry, const tchar *output_path,
-                 int extract_flags)
-{
-       int ret;
-       struct stat stbuf;
-
-       ret = tstat(output_path, &stbuf);
-       if (ret == 0) {
-               if (S_ISDIR(stbuf.st_mode)) {
-                       /*if (!is_root)*/
-                               /*WARNING("`%s' already exists", output_path);*/
-                       goto dir_exists;
-               } else {
-                       ERROR("`%"TS"' is not a directory", output_path);
-                       return WIMLIB_ERR_MKDIR;
-               }
-       } else {
-               if (errno != ENOENT) {
-                       ERROR_WITH_ERRNO("Failed to stat `%"TS"'", output_path);
-                       return WIMLIB_ERR_STAT;
-               }
-       }
-
-       if (tmkdir(output_path, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH))
-       {
-               ERROR_WITH_ERRNO("Cannot create directory `%"TS"'", output_path);
-               return WIMLIB_ERR_MKDIR;
-       }
-dir_exists:
-       ret = 0;
-#ifndef __WIN32__
-       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);
-       }
-#endif
-       return ret;
-}
-
-int
-unix_do_apply_dentry(const char *output_path, size_t output_path_len,
-                    struct wim_dentry *dentry, struct apply_args *args)
-{
-       const struct wim_inode *inode = dentry->d_inode;
-
-       if (inode_is_symlink(inode))
-               return extract_symlink(dentry, args, output_path);
-       else if (inode_is_directory(inode))
-               return extract_directory(dentry, output_path, args->extract_flags);
-       else
-               return extract_regular_file(dentry, args, output_path);
-}
-
-int
-unix_do_apply_dentry_timestamps(const char *output_path,
-                               size_t output_path_len,
-                               struct wim_dentry *dentry,
-                               struct apply_args *args)
+unix_set_timestamps(const tchar *path, u64 creation_time, u64 last_write_time,
+                   u64 last_access_time, struct apply_ctx *ctx)
 {
        int ret;
-       const struct wim_inode *inode = dentry->d_inode;
 
 #ifdef HAVE_UTIMENSAT
        /* Convert the WIM timestamps, which are accurate to 100 nanoseconds,
@@ -424,9 +156,9 @@ unix_do_apply_dentry_timestamps(const char *output_path,
         * 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);
+       ts[0] = wim_timestamp_to_timespec(last_access_time);
+       ts[1] = wim_timestamp_to_timespec(last_write_time);
+       ret = utimensat(AT_FDCWD, path, ts, AT_SYMLINK_NOFOLLOW);
        if (ret)
                ret = errno;
 #else
@@ -440,9 +172,9 @@ unix_do_apply_dentry_timestamps(const char *output_path,
                 * 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);
+               tv[0] = wim_timestamp_to_timeval(last_access_time);
+               tv[1] = wim_timestamp_to_timeval(last_write_time);
+               ret = lutimes(path, tv);
                if (ret)
                        ret = errno;
        #endif
@@ -456,15 +188,33 @@ unix_do_apply_dentry_timestamps(const char *output_path,
                 * 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);
+               buf.actime = wim_timestamp_to_unix(last_access_time);
+               buf.modtime = wim_timestamp_to_unix(last_write_time);
+               ret = utime(path, &buf);
        #endif
        }
-       if (ret && args->num_utime_warnings < 10) {
-               WARNING_WITH_ERRNO("Failed to set timestamp on file `%s'",
-                                   output_path);
-               args->num_utime_warnings++;
-       }
+       if (ret)
+               return WIMLIB_ERR_SET_TIMESTAMPS;
        return 0;
 }
+
+const struct apply_operations unix_apply_ops = {
+       .name = "UNIX",
+
+       .start_extract          = unix_start_extract,
+       .create_file            = unix_create_file,
+       .create_directory       = unix_create_directory,
+       .create_hardlink        = unix_create_hardlink,
+       .create_symlink         = unix_create_symlink,
+       .extract_unnamed_stream = unix_extract_unnamed_stream,
+       .set_unix_data          = unix_set_unix_data,
+       .set_timestamps         = unix_set_timestamps,
+
+       .path_separator = '/',
+       .path_max = PATH_MAX,
+
+       .requires_target_in_paths = 1,
+       .supports_case_sensitive_filenames = 1,
+};
+
+#endif /* !__WIN32__ */