If Xenstore config isn't available, use cmdline.

This change essentially decouples the bmk part of the Xen platform
from the rumprun userspace, essentially fixing "kernonly" mode on
Xen...  or at least making it possible to build a Xen kernonly image.

diff --git a/platform/xen/init.c b/platform/xen/init.c
index dc16946254858707ccb3a2261045da98f9855250..a62e871dca1690bca6fd00d6ab63c53d2a1ddc2d 100644 (file)
--- a/platform/xen/init.c
+++ b/platform/xen/init.c
@@ -35,37 +35,17 @@
 #include <bmk-core/platform.h>
 #include <bmk-core/printf.h>
 
-#include <rumprun-base/config.h>
-
-static char hardcoded_jsoncfg[] = "";
-
 static char *
-jsonordie(void)
-{
-
-       if (hardcoded_jsoncfg[0] == '\0')
-               bmk_platform_halt("could not get configuration");
-
-       bmk_printf("using hardcoded_jsoncfg\n");
-       return hardcoded_jsoncfg;
-}
-
-static char *
-get_config(char *cmdline)
+get_xenstorecfg(void)
 {
        xenbus_transaction_t txn;
        char *cfg;
        int retry;
 
-       /* XXX: should not be here */
-       cfg = rumprun_config_path(cmdline);
-       if (cfg != NULL)
-               return cfg;
-
        if (xenbus_transaction_start(&txn))
-               return jsonordie();
-       if (xenbus_read(txn, "rumprun/cfg", &cfg) != NULL)
-               cfg = jsonordie();
+               return NULL;
+       xenbus_read(txn, "rumprun/cfg", &cfg);
+       /* XXX: unclear what the "retry" param is supposed to signify */
        xenbus_transaction_end(txn, 0, &retry);
 
        return cfg;
@@ -74,9 +54,20 @@ get_config(char *cmdline)
 int
 app_main(start_info_t *si)
 {
-       void *cmdline;
+       char *cmdline;
+
+       /*
+        * So, what we currently do is:
+        *   1) try to fetch the config from xenstore.  if available, use that
+        *   2) else, just pass the command line to bmk_mainthread
+        *
+        * Not sure if we eventually need to pass both, but we can change
+        * it later.
+        */
+
+       if ((cmdline = get_xenstorecfg()) == NULL)
+               cmdline = (char *)si->cmd_line;
 
-       cmdline = get_config((char *)si->cmd_line);
        bmk_mainthread(cmdline);
        /* NOTREACHED */