]> wimlib.net Git - wimlib/blobdiff - programs/imagex.c
Fix sequential extraction, and include progress info
[wimlib] / programs / imagex.c
index fc89cdfe036aec38146f5dee6464b1d3f54a82d8..9b8af6e047d3caf16baaa544e9faefd4d55421f0 100644 (file)
 #include <string.h>
 #include <errno.h>
 #include <libgen.h>
+#include <limits.h>
 #include <sys/stat.h>
+#include <unistd.h>
+#include <inttypes.h>
 
 #define ARRAY_LEN(array) (sizeof(array) / sizeof(array[0]))
 
-#define swap(a, b) ({ typeof(a) __a = (a); typeof(b) __b = (b); \
-                               a = __b; b = __a; })
-
 #define for_opt(c, opts) while ((c = getopt_long_only(argc, (char**)argv, "", \
                                opts, NULL)) != -1)
 
@@ -53,6 +53,7 @@ enum imagex_op_type {
        JOIN,
        MOUNT,
        MOUNTRW,
+       OPTIMIZE,
        SPLIT,
        UNMOUNT,
 };
@@ -61,45 +62,48 @@ static void usage(int cmd_type);
 static void usage_all();
 
 static const char *usage_strings[] = {
-[APPEND] = 
-"    imagex append (DIRECTORY | NTFS_VOLUME) WIMFILE [IMAGE_NAME]\n"
-"                  [DESCRIPTION] [--boot] [--check] [--flags EDITION_ID]\n"
-"                  [--verbose] [--dereference] [--config=FILE]\n",
-[APPLY] = 
-"    imagex apply WIMFILE [IMAGE_NUM | IMAGE_NAME | all]\n"
-"                 (DIRECTORY | NTFS_VOLUME) [--check] [--hardlink]\n"
-"                 [--symlink] [--verbose] [--ref=\"GLOB\"]\n",
-[CAPTURE] = 
-"    imagex capture (DIRECTORY | NTFS_VOLUME) WIMFILE [IMAGE_NAME]\n"
-"                   [DESCRIPTION] [--boot] [--check] [--compress=TYPE]\n"
-"                   [--flags EDITION_ID] [--verbose] [--dereference]\n"
-"                   [--config=FILE]\n",
-[DELETE] = 
-"    imagex delete WIMFILE (IMAGE_NUM | IMAGE_NAME | all) [--check]\n",
-[DIR] = 
-"    imagex dir WIMFILE (IMAGE_NUM | IMAGE_NAME | all)\n",
-[EXPORT] = 
-"    imagex export SRC_WIMFILE (SRC_IMAGE_NUM | SRC_IMAGE_NAME | all ) \n"
-"                  DEST_WIMFILE [DEST_IMAGE_NAME]\n"
-"                  [DEST_IMAGE_DESCRIPTION] [--boot] [--check]\n"
-"                  [--compress=TYPE] [--ref=\"GLOB\"]\n",
-[INFO] = 
-"    imagex info WIMFILE [IMAGE_NUM | IMAGE_NAME] [NEW_NAME]\n"
-"                [NEW_DESC] [--boot] [--check] [--header] [--lookup-table]\n"
-"                [--xml] [--extract-xml FILE] [--metadata]\n",
-[JOIN] = 
-"    imagex join [--check] WIMFILE SPLIT_WIM...\n",
-[MOUNT] = 
-"    imagex mount WIMFILE (IMAGE_NUM | IMAGE_NAME) DIRECTORY\n"
-"                 [--check] [--debug] [--streams-interface=INTERFACE]\n"
-"                 [--ref=\"GLOB\"]\n",
-[MOUNTRW] = 
-"    imagex mountrw WIMFILE [IMAGE_NUM | IMAGE_NAME] DIRECTORY\n"
-"                   [--check] [--debug] [--streams-interface=INTERFACE]\n",
-[SPLIT] = 
-"    imagex split WIMFILE SPLIT_WIMFILE PART_SIZE_MB [--check]\n",
-[UNMOUNT] = 
-"    imagex unmount DIRECTORY [--commit] [--check]\n",
+[APPEND] =
+"imagex append (DIRECTORY | NTFS_VOLUME) WIMFILE [IMAGE_NAME]\n"
+"                     [DESCRIPTION] [--boot] [--check] [--flags EDITION_ID]\n"
+"                     [--verbose] [--dereference] [--config=FILE]\n"
+"                     [--threads=NUM_THREADS] [--rebuild]\n",
+[APPLY] =
+"imagex apply WIMFILE [IMAGE_NUM | IMAGE_NAME | all]\n"
+"                    (DIRECTORY | NTFS_VOLUME) [--check] [--hardlink]\n"
+"                    [--symlink] [--verbose] [--ref=\"GLOB\"]\n",
+[CAPTURE] =
+"imagex capture (DIRECTORY | NTFS_VOLUME) WIMFILE [IMAGE_NAME]\n"
+"                      [DESCRIPTION] [--boot] [--check] [--compress=TYPE]\n"
+"                      [--flags EDITION_ID] [--verbose] [--dereference]\n"
+"                      [--config=FILE] [--threads=NUM_THREADS]\n",
+[DELETE] =
+"imagex delete WIMFILE (IMAGE_NUM | IMAGE_NAME | all) [--check] [--soft]\n",
+[DIR] =
+"imagex dir WIMFILE (IMAGE_NUM | IMAGE_NAME | all)\n",
+[EXPORT] =
+"imagex export SRC_WIMFILE (SRC_IMAGE_NUM | SRC_IMAGE_NAME | all ) \n"
+"              DEST_WIMFILE [DEST_IMAGE_NAME] [DEST_IMAGE_DESCRIPTION]\n"
+"              [--boot] [--check] [--compress=TYPE] [--ref=\"GLOB\"]\n"
+"              [--threads=NUM_THREADS] [--rebuild]\n",
+[INFO] =
+"imagex info WIMFILE [IMAGE_NUM | IMAGE_NAME] [NEW_NAME]\n"
+"                   [NEW_DESC] [--boot] [--check] [--header] [--lookup-table]\n"
+"                   [--xml] [--extract-xml FILE] [--metadata]\n",
+[JOIN] =
+"imagex join [--check] WIMFILE SPLIT_WIM...\n",
+[MOUNT] =
+"imagex mount WIMFILE (IMAGE_NUM | IMAGE_NAME) DIRECTORY\n"
+"                    [--check] [--debug] [--streams-interface=INTERFACE]\n"
+"                    [--ref=\"GLOB\"]\n",
+[MOUNTRW] =
+"imagex mountrw WIMFILE [IMAGE_NUM | IMAGE_NAME] DIRECTORY\n"
+"                      [--check] [--debug] [--streams-interface=INTERFACE]\n",
+[OPTIMIZE] =
+"imagex optimize WIMFILE [--check] [--recompress]\n",
+[SPLIT] =
+"imagex split WIMFILE SPLIT_WIMFILE PART_SIZE_MB [--check]\n",
+[UNMOUNT] =
+"imagex unmount DIRECTORY [--commit] [--check]\n",
 };
 
 static const struct option common_options[] = {
@@ -124,10 +128,13 @@ static const struct option capture_or_append_options[] = {
        {"dereference", no_argument,       NULL, 'L'},
        {"flags",       required_argument, NULL, 'f'},
        {"verbose",     no_argument,       NULL, 'v'},
+       {"threads",     required_argument, NULL, 't'},
+       {"rebuild",     no_argument,       NULL, 'R'},
        {NULL, 0, NULL, 0},
 };
 static const struct option delete_options[] = {
        {"check", no_argument, NULL, 'c'},
+       {"soft",  no_argument, NULL, 's'},
        {NULL, 0, NULL, 0},
 };
 
@@ -136,6 +143,8 @@ static const struct option export_options[] = {
        {"check",      no_argument,       NULL, 'c'},
        {"compress",   required_argument, NULL, 'x'},
        {"ref",        required_argument, NULL, 'r'},
+       {"threads",    required_argument, NULL, 't'},
+       {"rebuild",    no_argument,       NULL, 'R'},
        {NULL, 0, NULL, 0},
 };
 
@@ -163,6 +172,12 @@ static const struct option mount_options[] = {
        {NULL, 0, NULL, 0},
 };
 
+static const struct option optimize_options[] = {
+       {"check",      no_argument, NULL, 'c'},
+       {"recompress", no_argument, NULL, 'r'},
+       {NULL, 0, NULL, 0},
+};
+
 static const struct option split_options[] = {
        {"check", no_argument, NULL, 'c'},
        {NULL, 0, NULL, 0},
@@ -199,29 +214,17 @@ static void imagex_error_with_errno(const char *format, ...)
        va_end(va);
 }
 
-static const char *path_basename(const char *path)
-{
-       const char *p = path;
-       while (*p)
-               p++;
-       p--;
-
-       /* Trailing slashes. */
-       while ((p != path - 1) && *p == '/')
-               p--;
-
-       while ((p != path - 1) && *p != '/')
-               p--;
-
-       return p + 1;
-}
-
-
-static int verify_image_exists(int image)
+static int verify_image_exists(int image, const char *image_name,
+                              const char *wim_name)
 {
        if (image == WIM_NO_IMAGE) {
-               imagex_error("Not a valid image");
-               return WIMLIB_ERR_INVALID_IMAGE;
+               imagex_error("\"%s\" is not a valid image in `%s'!\n"
+                            "       Please specify a 1-based imagex index or "
+                            "image name.\n"
+                            "       You may use `imagex info' to list the images "
+                            "contained in a WIM.",
+                            image_name, wim_name);
+               return -1;
        }
        return 0;
 }
@@ -229,16 +232,17 @@ static int verify_image_exists(int image)
 static int verify_image_is_single(int image)
 {
        if (image == WIM_ALL_IMAGES) {
-               imagex_error("Cannot specify all images for this action");
-               return WIMLIB_ERR_INVALID_IMAGE;
+               imagex_error("Cannot specify all images for this action!");
+               return -1;
        }
        return 0;
 }
 
-static int verify_image_exists_and_is_single(int image)
+static int verify_image_exists_and_is_single(int image, const char *image_name,
+                                            const char *wim_name)
 {
        int ret;
-       ret = verify_image_exists(image);
+       ret = verify_image_exists(image, image_name, wim_name);
        if (ret == 0)
                ret = verify_image_is_single(image);
        return ret;
@@ -259,6 +263,15 @@ static int get_compression_type(const char *optarg)
        }
 }
 
+static off_t file_get_size(const char *filename)
+{
+       struct stat st;
+       if (stat(filename, &st) == 0)
+               return st.st_size;
+       else
+               return (off_t)-1;
+}
+
 static char *file_get_contents(const char *filename, size_t *len_ret)
 {
        struct stat stbuf;
@@ -298,6 +311,15 @@ out_fclose:
        return NULL;
 }
 
+static int file_writable(const char *path)
+{
+       int ret;
+       ret = access(path, F_OK | W_OK);
+       if (ret != 0)
+               imagex_error_with_errno("Can't modify `%s'", path);
+       return ret;
+}
+
 static int open_swms_from_glob(const char *swm_glob,
                               const char *first_part,
                               int open_flags,
@@ -328,8 +350,8 @@ static int open_swms_from_glob(const char *swm_glob,
                ret = -1;
                goto out_globfree;
        }
-       size_t offset = 0;
-       for (size_t i = 0; i < num_additional_swms; i++) {
+       unsigned offset = 0;
+       for (unsigned i = 0; i < num_additional_swms; i++) {
                if (strcmp(globbuf.gl_pathv[i], first_part) == 0) {
                        offset++;
                        continue;
@@ -355,6 +377,19 @@ out:
 }
 
 
+static unsigned parse_num_threads(const char *optarg)
+{
+       char *tmp;
+       unsigned nthreads = strtoul(optarg, &tmp, 10);
+       if (nthreads == UINT_MAX || *tmp || tmp == optarg) {
+               imagex_error("Number of threads must be a non-negative integer!");
+               return UINT_MAX;
+       } else {
+               return nthreads;
+       }
+}
+
+
 /* Extract one image, or all images, from a WIM file into a directory. */
 static int imagex_apply(int argc, const char **argv)
 {
@@ -368,7 +403,8 @@ static int imagex_apply(int argc, const char **argv)
        const char *wimfile;
        const char *dir;
        const char *image_num_or_name;
-       int extract_flags = 0;
+       int extract_flags = WIMLIB_EXTRACT_FLAG_SEQUENTIAL |
+                           WIMLIB_EXTRACT_FLAG_SHOW_PROGRESS;
 
        const char *swm_glob = NULL;
        WIMStruct **additional_swms = NULL;
@@ -405,7 +441,7 @@ static int imagex_apply(int argc, const char **argv)
 
        wimfile = argv[0];
        if (argc == 2) {
-               image_num_or_name =  "1";
+               image_num_or_name = "1";
                dir = argv[1];
        } else {
                image_num_or_name = argv[1];
@@ -417,7 +453,7 @@ static int imagex_apply(int argc, const char **argv)
                return ret;
 
        image = wimlib_resolve_image(w, image_num_or_name);
-       ret = verify_image_exists(image);
+       ret = verify_image_exists(image, image_num_or_name, wimfile);
        if (ret != 0)
                goto out;
 
@@ -455,8 +491,11 @@ static int imagex_apply(int argc, const char **argv)
                        goto out;
                }
        } else {
-               if (errno != ENOENT)
+               if (errno != ENOENT) {
                        imagex_error_with_errno("Failed to stat `%s'", dir);
+                       ret = -1;
+                       goto out;
+               }
        }
 #endif
 
@@ -464,9 +503,11 @@ static int imagex_apply(int argc, const char **argv)
                                   additional_swms, num_additional_swms);
 out:
        wimlib_free(w);
-       if (additional_swms)
-               for (size_t i = 0; i < num_additional_swms; i++)
+       if (additional_swms) {
+               for (unsigned i = 0; i < num_additional_swms; i++)
                        wimlib_free(additional_swms[i]);
+               free(additional_swms);
+       }
        return ret;
 }
 
@@ -474,7 +515,7 @@ static int imagex_capture_or_append(int argc, const char **argv)
 {
        int c;
        int open_flags = WIMLIB_OPEN_FLAG_SHOW_PROGRESS;
-       int add_image_flags = 0;
+       int add_image_flags = WIMLIB_ADD_IMAGE_FLAG_SHOW_PROGRESS;
        int write_flags = WIMLIB_WRITE_FLAG_SHOW_PROGRESS;
        int compression_type = WIM_COMPRESSION_TYPE_XPRESS;
        const char *dir;
@@ -490,6 +531,7 @@ static int imagex_capture_or_append(int argc, const char **argv)
        int cur_image;
        char *default_name;
        int cmd = strcmp(argv[0], "append") ? CAPTURE : APPEND;
+       unsigned num_threads = 0;
 
        for_opt(c, capture_or_append_options) {
                switch (c) {
@@ -516,6 +558,15 @@ static int imagex_capture_or_append(int argc, const char **argv)
                        break;
                case 'v':
                        add_image_flags |= WIMLIB_ADD_IMAGE_FLAG_VERBOSE;
+                       write_flags |= WIMLIB_WRITE_FLAG_VERBOSE;
+                       break;
+               case 't':
+                       num_threads = parse_num_threads(optarg);
+                       if (num_threads == UINT_MAX)
+                               return -1;
+                       break;
+               case 'R':
+                       write_flags |= WIMLIB_WRITE_FLAG_REBUILD;
                        break;
                default:
                        usage(cmd);
@@ -528,15 +579,15 @@ static int imagex_capture_or_append(int argc, const char **argv)
                usage(cmd);
                return -1;
        }
-       dir     = argv[0];
+       dir = argv[0];
        wimfile = argv[1];
 
        char dir_copy[strlen(dir) + 1];
        memcpy(dir_copy, dir, strlen(dir) + 1);
        default_name = basename(dir_copy);
 
-       name    = (argc >= 3) ? argv[2] : default_name;
-       desc    = (argc >= 4) ? argv[3] : NULL;
+       name = (argc >= 3) ? argv[2] : default_name;
+       desc = (argc >= 4) ? argv[3] : NULL;
 
        if (config_file) {
                config_str = file_get_contents(config_file, &config_len);
@@ -592,10 +643,14 @@ out_write:
                if (ret != 0)
                        goto out;
        }
-       if (cmd == APPEND)
-               ret = wimlib_overwrite(w, write_flags);
-       else
-               ret = wimlib_write(w, wimfile, WIM_ALL_IMAGES, write_flags);
+       if (cmd == APPEND) {
+               ret = wimlib_overwrite(w, write_flags, num_threads);
+       } else {
+               ret = wimlib_write(w, wimfile, WIM_ALL_IMAGES, write_flags,
+                                  num_threads);
+       }
+       if (ret == WIMLIB_ERR_REOPEN)
+               ret = 0;
        if (ret != 0)
                imagex_error("Failed to write the WIM file `%s'", wimfile);
 out:
@@ -622,6 +677,9 @@ static int imagex_delete(int argc, const char **argv)
                        open_flags |= WIMLIB_OPEN_FLAG_CHECK_INTEGRITY;
                        write_flags |= WIMLIB_WRITE_FLAG_CHECK_INTEGRITY;
                        break;
+               case 's':
+                       write_flags |= WIMLIB_WRITE_FLAG_SOFT_DELETE;
+                       break;
                default:
                        usage(DELETE);
                        return -1;
@@ -641,28 +699,34 @@ static int imagex_delete(int argc, const char **argv)
        wimfile = argv[0];
        image_num_or_name = argv[1];
 
+       ret = file_writable(wimfile);
+       if (ret != 0)
+               return ret;
+
        ret = wimlib_open_wim(wimfile, open_flags, &w);
        if (ret != 0)
                return ret;
 
        image = wimlib_resolve_image(w, image_num_or_name);
 
-       ret = verify_image_exists(image);
+       ret = verify_image_exists(image, image_num_or_name, wimfile);
        if (ret != 0)
-               goto done;
+               goto out;
 
        ret = wimlib_delete_image(w, image);
        if (ret != 0) {
                imagex_error("Failed to delete image from `%s'", wimfile);
-               goto done;
+               goto out;
        }
 
-       ret = wimlib_overwrite(w, write_flags);
+       ret = wimlib_overwrite(w, write_flags, 0);
+       if (ret == WIMLIB_ERR_REOPEN)
+               ret = 0;
        if (ret != 0) {
                imagex_error("Failed to write the file `%s' with image "
                             "deleted", wimfile);
        }
-done:
+out:
        wimlib_free(w);
        return ret;
 }
@@ -675,7 +739,6 @@ static int imagex_dir(int argc, const char **argv)
        int image;
        int ret;
        int num_images;
-       int part_number;
 
        if (argc < 2) {
                imagex_error("Must specify a WIM file");
@@ -693,20 +756,11 @@ static int imagex_dir(int argc, const char **argv)
        if (ret != 0)
                return ret;
 
-       part_number = wimlib_get_part_number(w, NULL);
-       if (part_number != 1) {
-               imagex_error("`%s' is part %d of a split WIM!  Specify the "
-                            "first part to see the files",
-                            wimfile, part_number);
-               ret = WIMLIB_ERR_SPLIT_UNSUPPORTED;
-               goto done;
-       }
-
        if (argc == 3) {
                image = wimlib_resolve_image(w, argv[2]);
-               ret = verify_image_exists(image);
+               ret = verify_image_exists(image, argv[2], wimfile);
                if (ret != 0)
-                       goto done;
+                       goto out;
        } else {
                /* Image was not specified.  If the WIM only contains one image,
                 * choose that one; otherwise, print an error. */
@@ -716,13 +770,13 @@ static int imagex_dir(int argc, const char **argv)
                                     "select one.", wimfile, num_images);
                        usage(DIR);
                        ret = -1;
-                       goto done;
+                       goto out;
                }
                image = 1;
        }
 
        ret = wimlib_print_files(w, image);
-done:
+out:
        wimlib_free(w);
        return ret;
 }
@@ -735,7 +789,7 @@ static int imagex_export(int argc, const char **argv)
        int open_flags = WIMLIB_OPEN_FLAG_SHOW_PROGRESS;
        int export_flags = 0;
        int write_flags = WIMLIB_WRITE_FLAG_SHOW_PROGRESS;
-       int compression_type = WIM_COMPRESSION_TYPE_XPRESS;
+       int compression_type;
        bool compression_type_specified = false;
        const char *src_wimfile;
        const char *src_image_num_or_name;
@@ -751,6 +805,7 @@ static int imagex_export(int argc, const char **argv)
        const char *swm_glob = NULL;
        WIMStruct **additional_swms = NULL;
        unsigned num_additional_swms = 0;
+       unsigned num_threads = 0;
 
        for_opt(c, export_options) {
                switch (c) {
@@ -770,6 +825,14 @@ static int imagex_export(int argc, const char **argv)
                case 'r':
                        swm_glob = optarg;
                        break;
+               case 't':
+                       num_threads = parse_num_threads(optarg);
+                       if (num_threads == UINT_MAX)
+                               return -1;
+                       break;
+               case 'R':
+                       write_flags |= WIMLIB_WRITE_FLAG_REBUILD;
+                       break;
                default:
                        usage(EXPORT);
                        return -1;
@@ -791,33 +854,44 @@ static int imagex_export(int argc, const char **argv)
        if (ret != 0)
                return ret;
 
-       /* Determine if the destination is an existing file or not.  
+       /* Determine if the destination is an existing file or not.
         * If so, we try to append the exported image(s) to it; otherwise, we
         * create a new WIM containing the exported image(s). */
        if (stat(dest_wimfile, &stbuf) == 0) {
+               int dest_ctype;
+
                wim_is_new = false;
                /* Destination file exists. */
                if (!S_ISREG(stbuf.st_mode) && !S_ISLNK(stbuf.st_mode)) {
                        imagex_error("`%s' is not a regular file",
                                        dest_wimfile);
+                       ret = -1;
                        goto out;
                }
                ret = wimlib_open_wim(dest_wimfile, open_flags, &dest_w);
                if (ret != 0)
                        goto out;
 
-               if (compression_type_specified && compression_type != 
-                               wimlib_get_compression_type(dest_w)) {
+               ret = file_writable(dest_wimfile);
+               if (ret != 0)
+                       return ret;
+
+               dest_ctype = wimlib_get_compression_type(dest_w);
+               if (compression_type_specified
+                   && compression_type != dest_ctype)
+               {
                        imagex_error("Cannot specify a compression type that is "
                                     "not the same as that used in the "
                                     "destination WIM");
                        ret = -1;
                        goto out;
                }
-               compression_type = wimlib_get_compression_type(dest_w);
+               compression_type = dest_ctype;
        } else {
                wim_is_new = true;
                /* dest_wimfile is not an existing file, so create a new WIM. */
+               if (!compression_type_specified)
+                       compression_type = wimlib_get_compression_type(src_w);
                if (errno == ENOENT) {
                        ret = wimlib_create_new_wim(compression_type, &dest_w);
                        if (ret != 0)
@@ -825,12 +899,13 @@ static int imagex_export(int argc, const char **argv)
                } else {
                        imagex_error_with_errno("Cannot stat file `%s'",
                                                dest_wimfile);
+                       ret = -1;
                        goto out;
                }
        }
 
        image = wimlib_resolve_image(src_w, src_image_num_or_name);
-       ret = verify_image_exists(image);
+       ret = verify_image_exists(image, src_image_num_or_name, src_wimfile);
        if (ret != 0)
                goto out;
 
@@ -842,7 +917,7 @@ static int imagex_export(int argc, const char **argv)
                        goto out;
        }
 
-       ret = wimlib_export_image(src_w, image, dest_w, dest_name, dest_desc, 
+       ret = wimlib_export_image(src_w, image, dest_w, dest_name, dest_desc,
                                  export_flags, additional_swms,
                                  num_additional_swms);
        if (ret != 0)
@@ -850,16 +925,20 @@ static int imagex_export(int argc, const char **argv)
 
 
        if (wim_is_new)
-               ret = wimlib_write(dest_w, dest_wimfile, WIM_ALL_IMAGES, 
-                                  write_flags);
+               ret = wimlib_write(dest_w, dest_wimfile, WIM_ALL_IMAGES,
+                                  write_flags, num_threads);
        else
-               ret = wimlib_overwrite(dest_w, write_flags);
+               ret = wimlib_overwrite(dest_w, write_flags, num_threads);
 out:
+       if (ret == WIMLIB_ERR_REOPEN)
+               ret = 0;
        wimlib_free(src_w);
        wimlib_free(dest_w);
-       if (additional_swms)
+       if (additional_swms) {
                for (unsigned i = 0; i < num_additional_swms; i++)
                        wimlib_free(additional_swms[i]);
+               free(additional_swms);
+       }
        return ret;
 }
 
@@ -884,7 +963,7 @@ static int imagex_info(int argc, const char **argv)
        FILE *fp;
        int image;
        int ret;
-       int open_flags = WIMLIB_OPEN_FLAG_SHOW_PROGRESS | 
+       int open_flags = WIMLIB_OPEN_FLAG_SHOW_PROGRESS |
                         WIMLIB_OPEN_FLAG_SPLIT_OK;
        int part_number;
        int total_parts;
@@ -936,7 +1015,7 @@ static int imagex_info(int argc, const char **argv)
                        new_name = argv[2];
                        if (argc > 3) {
                                new_desc = argv[3];
-                       } 
+                       }
                }
        }
 
@@ -949,23 +1028,16 @@ static int imagex_info(int argc, const char **argv)
 
        part_number = wimlib_get_part_number(w, &total_parts);
 
-       /*if (total_parts > 1 && part_number > 1) {*/
-               /*printf("Warning: this is part %d of a %d-part split WIM.\n"*/
-                      /*"         Select the first part if you want to see information\n"*/
-                      /*"         about images in the WIM.\n", */
-                      /*part_number, total_parts);*/
-       /*}*/
-
        image = wimlib_resolve_image(w, image_num_or_name);
        if (image == WIM_NO_IMAGE && strcmp(image_num_or_name, "0") != 0) {
-               imagex_error("The image `%s' does not exist", 
+               imagex_error("The image `%s' does not exist",
                                                image_num_or_name);
                if (boot)
                        imagex_error("If you would like to set the boot "
                                     "index to 0, specify image \"0\" with "
                                     "the --boot flag.");
                ret = WIMLIB_ERR_INVALID_IMAGE;
-               goto done;
+               goto out;
        }
 
        if (image == WIM_ALL_IMAGES && wimlib_get_num_images(w) > 1) {
@@ -974,14 +1046,14 @@ static int imagex_info(int argc, const char **argv)
                                     "without specifying a specific "
                                     "image in a multi-image WIM");
                        ret = WIMLIB_ERR_INVALID_IMAGE;
-                       goto done;
+                       goto out;
                }
                if (new_name) {
                        imagex_error("Cannot specify the NEW_NAME "
                                     "without specifying a specific "
                                     "image in a multi-image WIM");
                        ret = WIMLIB_ERR_INVALID_IMAGE;
-                       goto done;
+                       goto out;
                }
        }
 
@@ -989,11 +1061,13 @@ static int imagex_info(int argc, const char **argv)
         * recreate the WIM file. */
        if (!new_name && !boot) {
 
+               /* Read-only operations */
+
                if (image == WIM_NO_IMAGE) {
                        imagex_error("`%s' is not a valid image",
                                     image_num_or_name);
                        ret = WIMLIB_ERR_INVALID_IMAGE;
-                       goto done;
+                       goto out;
                }
 
                if (image == WIM_ALL_IMAGES && short_header)
@@ -1014,7 +1088,7 @@ static int imagex_info(int argc, const char **argv)
                if (xml) {
                        ret = wimlib_extract_xml_data(w, stdout);
                        if (ret != 0)
-                               goto done;
+                               goto out;
                }
 
                if (xml_out_file) {
@@ -1024,17 +1098,17 @@ static int imagex_info(int argc, const char **argv)
                                                        "file `%s' for "
                                                        "writing ",
                                                        xml_out_file);
-                               goto done;
+                               goto out;
                        }
                        ret = wimlib_extract_xml_data(w, fp);
                        if (fclose(fp) != 0) {
                                imagex_error("Failed to close the file `%s'",
                                             xml_out_file);
-                               goto done;
+                               goto out;
                        }
 
                        if (ret != 0)
-                               goto done;
+                               goto out;
                }
 
                if (short_header)
@@ -1043,9 +1117,11 @@ static int imagex_info(int argc, const char **argv)
                if (metadata) {
                        ret = wimlib_print_metadata(w, image);
                        if (ret != 0)
-                               goto done;
+                               goto out;
                }
        } else {
+
+               /* Modification operations */
                if (total_parts != 1) {
                        imagex_error("Modifying a split WIM is not supported.");
                        return -1;
@@ -1071,7 +1147,7 @@ static int imagex_info(int argc, const char **argv)
                        }
                }
                if (new_name) {
-                       if (strcmp(wimlib_get_image_name(w, image), 
+                       if (strcmp(wimlib_get_image_name(w, image),
                                                new_name) == 0) {
                                printf("Image %d is already named \"%s\".\n",
                                       image, new_name);
@@ -1081,7 +1157,7 @@ static int imagex_info(int argc, const char **argv)
                                       "\"%s\".\n", image, new_name);
                                ret = wimlib_set_image_name(w, image, new_name);
                                if (ret != 0)
-                                       goto done;
+                                       goto out;
                        }
                }
                if (new_desc) {
@@ -1094,29 +1170,40 @@ static int imagex_info(int argc, const char **argv)
                        } else {
                                printf("Changing the description of image %d "
                                       "to \"%s\".\n", image, new_desc);
-                               ret = wimlib_set_image_descripton(w, image, 
+                               ret = wimlib_set_image_descripton(w, image,
                                                                  new_desc);
                                if (ret != 0)
-                                       goto done;
+                                       goto out;
                        }
                }
 
-               /* Only call wimlib_overwrite_xml_and_header() if something
-                * actually needs to be changed. */
-               if (boot || new_name || new_desc || 
+               /* Only call wimlib_overwrite() if something actually needs to
+                * be changed. */
+               if (boot || new_name || new_desc ||
                                check != wimlib_has_integrity_table(w)) {
 
-                       ret = wimlib_overwrite_xml_and_header(w, check ? 
-                                       WIMLIB_WRITE_FLAG_CHECK_INTEGRITY | 
-                                       WIMLIB_WRITE_FLAG_SHOW_PROGRESS : 0);
+                       ret = file_writable(wimfile);
+                       if (ret != 0)
+                               return ret;
+
+                       int write_flags;
+                       if (check) {
+                               write_flags = WIMLIB_WRITE_FLAG_CHECK_INTEGRITY |
+                                             WIMLIB_WRITE_FLAG_SHOW_PROGRESS;
+                       } else {
+                               write_flags = 0;
+                       }
+
+                       ret = wimlib_overwrite(w, write_flags, 1);
+                       if (ret == WIMLIB_ERR_REOPEN)
+                               ret = 0;
                } else {
                        printf("The file `%s' was not modified because nothing "
                                        "needed to be done.\n", wimfile);
                        ret = 0;
                }
        }
-
-done:
+out:
        wimlib_free(w);
        return ret;
 }
@@ -1171,6 +1258,7 @@ static int imagex_mount_rw_or_ro(int argc, const char **argv)
 
        if (strcmp(argv[0], "mountrw") == 0)
                mount_flags |= WIMLIB_MOUNT_FLAG_READWRITE;
+
        for_opt(c, mount_options) {
                switch (c) {
                case 'c':
@@ -1222,21 +1310,26 @@ static int imagex_mount_rw_or_ro(int argc, const char **argv)
                num_images = wimlib_get_num_images(w);
                if (num_images != 1) {
                        imagex_error("The file `%s' contains %d images; Please "
-                                    "select one", wimfile, num_images);
-                       usage((mount_flags & WIMLIB_MOUNT_FLAG_READWRITE)  
+                                    "select one.", wimfile, num_images);
+                       usage((mount_flags & WIMLIB_MOUNT_FLAG_READWRITE)
                                        ? MOUNTRW : MOUNT);
-                       ret = WIMLIB_ERR_INVALID_IMAGE;
+                       ret = -1;
                        goto out;
                }
                dir = argv[1];
        } else {
                image = wimlib_resolve_image(w, argv[1]);
                dir = argv[2];
+               ret = verify_image_exists_and_is_single(image, argv[1], wimfile);
+               if (ret != 0)
+                       goto out;
        }
 
-       ret = verify_image_exists_and_is_single(image);
-       if (ret != 0)
-               goto out;
+       if (mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) {
+               ret = file_writable(wimfile);
+               if (ret != 0)
+                       return ret;
+       }
 
        ret = wimlib_mount(w, image, dir, mount_flags, additional_swms,
                           num_additional_swms);
@@ -1247,22 +1340,93 @@ static int imagex_mount_rw_or_ro(int argc, const char **argv)
        }
 out:
        wimlib_free(w);
-       if (additional_swms)
+       if (additional_swms) {
                for (unsigned i = 0; i < num_additional_swms; i++)
                        wimlib_free(additional_swms[i]);
+               free(additional_swms);
+       }
        return ret;
 mount_usage:
-       usage((mount_flags & WIMLIB_MOUNT_FLAG_READWRITE)  
+       usage((mount_flags & WIMLIB_MOUNT_FLAG_READWRITE)
                        ? MOUNTRW : MOUNT);
        return -1;
 }
 
+static int imagex_optimize(int argc, const char **argv)
+{
+       int c;
+       int open_flags = WIMLIB_OPEN_FLAG_SHOW_PROGRESS;
+       int write_flags = WIMLIB_WRITE_FLAG_REBUILD |
+                         WIMLIB_WRITE_FLAG_SHOW_PROGRESS;
+       int ret;
+       WIMStruct *w;
+       const char *wimfile;
+       off_t old_size;
+       off_t new_size;
+
+       for_opt(c, optimize_options) {
+               switch (c) {
+               case 'c':
+                       open_flags |= WIMLIB_OPEN_FLAG_CHECK_INTEGRITY;
+                       write_flags |= WIMLIB_WRITE_FLAG_CHECK_INTEGRITY;
+                       break;
+               case 'r':
+                       write_flags |= WIMLIB_WRITE_FLAG_RECOMPRESS;
+                       break;
+               default:
+                       usage(OPTIMIZE);
+                       return -1;
+               }
+       }
+       argc -= optind;
+       argv += optind;
+
+       if (argc != 1) {
+               usage(OPTIMIZE);
+               return -1;
+       }
+
+       wimfile = argv[0];
+
+       ret = wimlib_open_wim(wimfile, open_flags, &w);
+       if (ret != 0)
+               return ret;
+
+       old_size = file_get_size(argv[0]);
+       printf("`%s' original size: ", wimfile);
+       if (old_size == -1)
+               puts("Unknown");
+       else
+               printf("%"PRIu64" KiB\n", old_size >> 10);
+
+       ret = wimlib_overwrite(w, write_flags, 0);
+
+       new_size = file_get_size(argv[0]);
+       printf("`%s' optimized size: ", wimfile);
+       if (new_size == -1)
+               puts("Unknown");
+       else
+               printf("%"PRIu64" KiB\n", new_size >> 10);
+
+       fputs("Space saved: ", stdout);
+       if (new_size != -1 && old_size != -1) {
+               printf("%lld KiB\n",
+                      ((long long)old_size - (long long)new_size) >> 10);
+       } else {
+               puts("Unknown");
+       }
+
+       wimlib_free(w);
+       return ret;
+}
+
 /* Split a WIM into a spanned set */
 static int imagex_split(int argc, const char **argv)
 {
        int c;
        int flags = WIMLIB_OPEN_FLAG_SHOW_PROGRESS;
        unsigned long part_size;
+       char *tmp;
 
        for_opt(c, split_options) {
                switch (c) {
@@ -1281,7 +1445,12 @@ static int imagex_split(int argc, const char **argv)
                usage(SPLIT);
                return -1;
        }
-       part_size = strtoul(argv[2], NULL, 10) * (1 << 20);
+       part_size = strtod(argv[2], &tmp) * (1 << 20);
+       if (tmp == argv[2] || *tmp) {
+               imagex_error("Invalid part size \"%s\"", argv[2]);
+               imagex_error("The part size must be an integer or floating-point number of megabytes.");
+               return -1;
+       }
        return wimlib_split(argv[0], argv[1], part_size, flags);
 }
 
@@ -1328,24 +1497,25 @@ struct imagex_command {
 #define for_imagex_command(p) for (p = &imagex_commands[0]; \
                p != &imagex_commands[ARRAY_LEN(imagex_commands)]; p++)
 
-static struct imagex_command imagex_commands[] = {
+static const struct imagex_command imagex_commands[] = {
        {"append",  imagex_capture_or_append, APPEND},
-       {"apply",   imagex_apply,          APPLY},
+       {"apply",   imagex_apply,             APPLY},
        {"capture", imagex_capture_or_append, CAPTURE},
-       {"delete",  imagex_delete,         DELETE},
-       {"dir",     imagex_dir,            DIR},
-       {"export",  imagex_export,         EXPORT},
-       {"info",    imagex_info,           INFO},
-       {"join",    imagex_join,           JOIN},
-       {"mount",   imagex_mount_rw_or_ro, MOUNT},
-       {"mountrw", imagex_mount_rw_or_ro, MOUNTRW},
-       {"split",   imagex_split,          SPLIT},
-       {"unmount", imagex_unmount,        UNMOUNT},
+       {"delete",  imagex_delete,            DELETE},
+       {"dir",     imagex_dir,               DIR},
+       {"export",  imagex_export,            EXPORT},
+       {"info",    imagex_info,              INFO},
+       {"join",    imagex_join,              JOIN},
+       {"mount",   imagex_mount_rw_or_ro,    MOUNT},
+       {"mountrw", imagex_mount_rw_or_ro,    MOUNTRW},
+       {"optimize",imagex_optimize,          OPTIMIZE},
+       {"split",   imagex_split,             SPLIT},
+       {"unmount", imagex_unmount,           UNMOUNT},
 };
 
 static void version()
 {
-       static const char *s = 
+       static const char *s =
        "imagex (" PACKAGE ") " PACKAGE_VERSION "\n"
        "Copyright (C) 2012 Eric Biggers\n"
        "License GPLv3+; GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.\n"
@@ -1361,7 +1531,7 @@ static void help_or_version(int argc, const char **argv)
 {
        int i;
        const char *p;
-       struct imagex_command *cmd;
+       const struct imagex_command *cmd;
 
        for (i = 1; i < argc; i++) {
                p = argv[i];
@@ -1371,7 +1541,7 @@ static void help_or_version(int argc, const char **argv)
                        continue;
                if (*p == '-')
                        p++;
-               if (strcmp(p, "help") == 0 || (*p == '?' && *(p + 1) == '\0')) {
+               if (strcmp(p, "help") == 0) {
                        for_imagex_command(cmd) {
                                if (strcmp(cmd->name, argv[1]) == 0) {
                                        usage(cmd->cmd);
@@ -1391,21 +1561,21 @@ static void help_or_version(int argc, const char **argv)
 
 static void usage(int cmd_type)
 {
-       struct imagex_command *cmd;
-       puts("IMAGEX: Usage:");
-       fputs(usage_strings[cmd_type], stdout);
-       for_imagex_command(cmd)
+       const struct imagex_command *cmd;
+       printf("Usage: %s", usage_strings[cmd_type]);
+       for_imagex_command(cmd) {
                if (cmd->cmd == cmd_type)
                        printf("\nTry `man imagex-%s' for more details.\n",
                               cmd->name);
+       }
 }
 
 static void usage_all()
 {
        puts("IMAGEX: Usage:");
        for (int i = 0; i < ARRAY_LEN(usage_strings); i++)
-               fputs(usage_strings[i], stdout);
-       static const char *extra = 
+               printf("    %s", usage_strings[i]);
+       static const char *extra =
 "    imagex --help\n"
 "    imagex --version\n"
 "\n"
@@ -1419,7 +1589,7 @@ static void usage_all()
 
 int main(int argc, const char **argv)
 {
-       struct imagex_command *cmd;
+       const struct imagex_command *cmd;
        int ret;
 
        if (argc < 2) {
@@ -1452,10 +1622,3 @@ int main(int argc, const char **argv)
        usage_all();
        return 1;
 }
-/*#ifndef WITH_NTFS_3G*/
-               /*ERROR("wimlib was not compiled with support for NTFS-3g, so we cannot extract");*/
-               /*ERROR("a WIM to a NTFS filesystem while preserving NTFS-specific metadata.");*/
-               /*ERROR("Please apply the WIM to a directory rather than a block device, ");*/
-               /*ERROR("and without the NTFS flag; or compile in support for NTFS-3g.");*/
-               /*return WIMLIB_ERR_UNSUPPORTED;*/
-/*#endif*/