wimlib-imagex: try harder to optimize out opening template WIM
authorEric Biggers <ebiggers3@gmail.com>
Sun, 21 Jan 2018 21:47:10 +0000 (13:47 -0800)
committerEric Biggers <ebiggers3@gmail.com>
Sun, 21 Jan 2018 21:47:10 +0000 (13:47 -0800)
As an optimization, 'wimcapture' and 'wimappend' don't separately open
the template WIM for --update-of if no filename is specified in that
option, which makes it default to either the single base WIM
(--delta-from), or the WIM being appended to.

Extend that optimization to cases where the filename is specified in
--update-of and it exactly matches the filename of the WIM being
appended to or any of the base WIMs.

programs/imagex.c

index 10f5455..69d7a6c 100644 (file)
@@ -1867,7 +1867,7 @@ imagex_capture_or_append(int argc, tchar **argv, int cmd)
        STRING_LIST(base_wimfiles);
        WIMStruct **base_wims;
 
-       WIMStruct *template_wim;
+       WIMStruct *template_wim = NULL;
        const tchar *template_wimfile = NULL;
        const tchar *template_image_name_or_num = NULL;
        int template_image = WIMLIB_NO_IMAGE;
@@ -2286,13 +2286,19 @@ imagex_capture_or_append(int argc, tchar **argv, int cmd)
         * open the WIM if needed and parse the image index.  */
        if (template_image_name_or_num) {
 
-
-               if (base_wimfiles.num_strings == 1 &&
-                   template_wimfile == base_wimfiles.strings[0]) {
-                       template_wim = base_wims[0];
-               } else if (template_wimfile == wimfile) {
+               if (cmd == CMD_APPEND && !tstrcmp(template_wimfile, wimfile)) {
                        template_wim = wim;
                } else {
+                       for (size_t i = 0; i < base_wimfiles.num_strings; i++) {
+                               if (!tstrcmp(template_wimfile,
+                                            base_wimfiles.strings[i])) {
+                                       template_wim = base_wims[i];
+                                       break;
+                               }
+                       }
+               }
+
+               if (!template_wim) {
                        ret = wimlib_open_wim_with_progress(template_wimfile,
                                                            open_flags,
                                                            &template_wim,
@@ -2324,8 +2330,6 @@ imagex_capture_or_append(int argc, tchar **argv, int cmd)
                                                        template_wimfile);
                if (ret)
                        goto out_free_template_wim;
-       } else {
-               template_wim = NULL;
        }
 
        ret = wimlib_add_image_multisource(wim,
@@ -2377,10 +2381,13 @@ imagex_capture_or_append(int argc, tchar **argv, int cmd)
                                         write_flags, num_threads);
        }
 out_free_template_wim:
-       /* template_wim may alias base_wims[0] or wim.  */
-       if ((base_wimfiles.num_strings != 1 || template_wim != base_wims[0]) &&
-           template_wim != wim)
-               wimlib_free(template_wim);
+       /* 'template_wim' may alias 'wim' or any of the 'base_wims' */
+       if (template_wim == wim)
+               goto out_free_base_wims;
+       for (size_t i = 0; i < base_wimfiles.num_strings; i++)
+               if (template_wim == base_wims[i])
+                       goto out_free_base_wims;
+       wimlib_free(template_wim);
 out_free_base_wims:
        for (size_t i = 0; i < base_wimfiles.num_strings; i++)
                wimlib_free(base_wims[i]);