browser: use the reselection mechanism also after resizing and after help

Also rename some things to be more fitting.  And make sure that something
will be selected even when many files, including the selected one, have
disappeared.

src/browser.c

@@ -49,10 +49,11 @@ char *do_browser(char *path, DIR *dir)
     char *retval = NULL;
     int kbinput;
     bool old_const_update = ISSET(CONST_UPDATE);
-    char *prev_dir = NULL;
-	/* The directory we were in before backing up to "..". */
+    char *present_name = NULL;
+	/* The name of the currently selected file, or of the directory we
+	 * were in before backing up to "..". */
     size_t old_selected;
-	/* The selected file we had before the current selected file. */
+	/* The number of the selected file before the current selected file. */
     functionptrtype func;
 	/* The function of the key the user typed in. */
 
@@ -64,7 +65,7 @@ char *do_browser(char *path, DIR *dir)
 
     UNSET(CONST_UPDATE);
 
-  change_browser_directory:
+  read_directory_contents:
 	/* We come here when we refresh or select a new directory. */
 
     /* Start with no key pressed. */
@@ -85,13 +86,12 @@ char *do_browser(char *path, DIR *dir)
     /* Sort the file list. */
     qsort(filelist, filelist_len, sizeof(char *), diralphasort);
 
-    /* If prev_dir isn't NULL, select the directory saved in it, and
-     * then blow it away. */
-    if (prev_dir != NULL) {
-	browser_select_dirname(prev_dir);
+    /* If given, reselect the present_name and then discard it. */
+    if (present_name != NULL) {
+	browser_select_dirname(present_name);
 
-	free(prev_dir);
-	prev_dir = NULL;
+	free(present_name);
+	present_name = NULL;
     /* Otherwise, select the first file or directory in the list. */
     } else
 	selected = 0;
@@ -114,14 +114,16 @@ char *do_browser(char *path, DIR *dir)
 
 #ifndef NANO_TINY
 	if (kbinput == KEY_WINCH) {
-	    /* Rebuild the file list and sort it. */
-	    browser_init(present_path, opendir(present_path));
-	    qsort(filelist, filelist_len, sizeof(char *), diralphasort);
+	    /* Remember the selected file, to be able to reselect it. */
+	    present_name = strdup(filelist[selected]);
 
-	    /* Make sure the selected file is within range. */
-	    if (selected >= filelist_len)
-		selected = filelist_len - 1;
+	    /* Reopen the current directory. */
+	    dir = opendir(path);
+	    if (dir != NULL)
+		goto read_directory_contents;
 
+	    statusbar(_("Error reading %s: %s"), path, strerror(errno));
+	    beep();
 	    kbinput = ERR;
 	}
 #endif
@@ -174,18 +176,8 @@ char *do_browser(char *path, DIR *dir)
 
 	if (func == total_refresh) {
 	    total_redraw();
-
-	    /* Remember the selected file, to be able to reselect it. */
-	    prev_dir = strdup(filelist[selected]);
-
-	    /* Reopen the current directory. */
-	    dir = opendir(path);
-	    if (dir == NULL) {
-		statusbar(_("Error reading %s: %s"), path, strerror(errno));
-		beep();
-		continue;
-	    }
-	    goto change_browser_directory;
+	    /* Simulate a window resize to force a directory reread. */
+	    kbinput = KEY_WINCH;
 	} else if (func == do_help_void) {
 #ifndef DISABLE_HELP
 	    do_help_void();
@@ -272,7 +264,7 @@ char *do_browser(char *path, DIR *dir)
 	    /* Start over again with the new path value. */
 	    free(path);
 	    path = new_path;
-	    goto change_browser_directory;
+	    goto read_directory_contents;
 	} else if (func == do_up_void) {
 	    if (selected >= width)
 		selected -= width;
@@ -333,12 +325,12 @@ char *do_browser(char *path, DIR *dir)
 	    /* If we moved up one level, remember where we came from, so
 	     * this directory can be highlighted and easily reentered. */
 	    if (strcmp(tail(filelist[selected]), "..") == 0)
-		prev_dir = striponedir(filelist[selected]);
+		present_name = striponedir(filelist[selected]);
 
 	    path = mallocstrcpy(path, filelist[selected]);
 
 	    /* Start over again with the new path value. */
-	    goto change_browser_directory;
+	    goto read_directory_contents;
 	} else if (func == do_exit) {
 	    /* Exit from the file browser. */
 	    break;
@@ -697,8 +689,13 @@ void browser_select_dirname(const char *needle)
 
     /* If the sought name isn't found, move the highlight so that the
      * changed selection will be noticed. */
-    if (looking_at == filelist_len)
+    if (looking_at == filelist_len) {
 	--selected;
+
+	/* Make sure we stay within the available range. */
+	if (selected >= filelist_len)
+	    selected = filelist_len - 1;
+    }
 }
 
 /* Set up the system variables for a filename search.  Return -1 or -2 if