Change Windows startup

remove the safeproc pseudo-windowport routines from
almost a decade ago.

A very early pass is made through the config file,
seeking out just the interface-related OPTIONS=windowport
and OPTIONS=soundlib and ignoring all other options in the
config file during that early pass, so the windowport
can be activated without the NetHack core initialization
in place that some of the other rcfile OPTIONS require.

Bundles the existing rcfile processing code into rcfile().

New functions to control which rcfile options will be
disregarded in the early config file pass, and which will be
processed:

    set_all_options_disregarded();
    set_all_options_heeded();
    disregard_this_option(opt_xx);
    heed_this_option(opt_xx);

Windows calls rcfile_interface_options(), which is
a bundling of a series of function calls to achieve
the desired result.

    void
    rcfile_interface_options(void)
    {
        allopt_array_init();
        set_all_options_disregarded();
        heed_this_option(opt_windowtype);
        heed_this_option(opt_soundlib);
        rcfile();
        set_all_options_heeded();
        disregard_this_option(opt_windowtype);
        disregard_this_option(opt_soundlib);
    }

src/cfgfiles.c

@@ -1881,6 +1881,85 @@ vconfig_error_add(const char *str, va_list the_args)
     config_erradd(buf);
 }
 
+void
+rcfile(void)
+{
+    char *opts = 0, *xtraopts = 0;
+    const char *envname, *namesrc, *nameval;
+
+    go.opt_phase = environ_opt;
+    /* getenv() instead of nhgetenv(): let total length of options be long;
+       parseoptions() will check each individually */
+    envname = "NETHACKOPTIONS";
+    opts = getenv(envname);
+    if (!opts) {
+        /* fall back to original name; discouraged */
+        envname = "HACKOPTIONS";
+        opts = getenv(envname);
+    }
+
+    if (gc.cmdline_rcfile) {
+        namesrc = "command line";
+        nameval = gc.cmdline_rcfile;
+        xtraopts = opts;
+        if (opts && (*opts == '/' || *opts == '\\' || *opts == '@'))
+            xtraopts = 0; /* NETHACKOPTIONS is a file name; ignore it */
+    } else if (opts && (*opts == '/' || *opts == '\\' || *opts == '@')) {
+        /* NETHACKOPTIONS is a file name; use that instead of the default */
+        if (*opts == '@')
+            ++opts; /* @filename */
+        namesrc = envname;
+        nameval = opts;
+        xtraopts = 0;
+    } else {
+        /* either no NETHACKOPTIONS or it wasn't a file name;
+           read the default configuration file */
+        nameval = namesrc = 0;
+        xtraopts = opts;
+    }
+
+    go.opt_phase = rc_file_opt;
+    /* seemingly arbitrary name length restriction is to prevent error
+       messages, if any were to be delivered while accessing the file,
+       from potentially overflowing buffers */
+    if (nameval && (int) strlen(nameval) >= BUFSZ / 2) {
+        config_error_init(TRUE, namesrc, FALSE);
+        config_error_add(
+            "nethackrc file name \"%.40s\"... too long; using default",
+            nameval);
+        config_error_done();
+        nameval = namesrc = 0; /* revert to default nethackrc */
+    }
+
+    config_error_init(TRUE, nameval, nameval ? CONFIG_ERROR_SECURE : FALSE);
+    (void) read_config_file(nameval, set_in_config);
+    config_error_done();
+    if (xtraopts) {
+        /* NETHACKOPTIONS is present and not a file name */
+        go.opt_phase = environ_opt;
+        config_error_init(FALSE, envname, FALSE);
+        (void) parseoptions(xtraopts, TRUE, FALSE);
+        config_error_done();
+    }
+
+    if (gc.cmdline_rcfile)
+        free((genericptr_t) gc.cmdline_rcfile), gc.cmdline_rcfile = 0;
+    /*[end of nethackrc handling]*/
+}
+
+void
+rcfile_interface_options(void)
+{
+    allopt_array_init();
+    set_all_options_disregarded();
+    heed_this_option(opt_windowtype);
+    heed_this_option(opt_soundlib);
+    rcfile();
+    set_all_options_heeded();
+    disregard_this_option(opt_windowtype);
+    disregard_this_option(opt_soundlib);
+}
+
 #ifdef SYSCF
 #ifdef SYSCF_FILE
 void