From: Andrew Deason <adeason@sinenomine.net>
Date: Tue, 10 Mar 2020 21:05:47 +0000 (-0500)
Subject: rxgen: Properly generate brief union default arm
X-Git-Tag: openafs-devel-1_9_0~124
X-Git-Url: http://git.openafs.org/?p=openafs.git;a=commitdiff_plain;h=abbadd3f4bf6fddc794b87d8d993ed6536c591e3

rxgen: Properly generate brief union default arm

Commit 13ae3de3 (Add "brief" option to rxgen) added the -b option to
rxgen, which (among other things) makes rxgen stop including the name
of an RPC-L union type within its fields. That is, instead of this:

    struct foo_type {
        afs_int32 foo_tag;
        union {
            /* ... */
        } foo_type_u;
    };

rxgen -b generates this:

    struct foo_type {
        afs_int32 foo_tag;
        union {
            /* ... */
        } u;
    };

And all of the autogenerated XDR code is altered to use the 'u' field
instead of foo_type_u. However, if a 'default:' arm is defined in the
definition for the RPC-L union, the autogenerated XDR code still tries
to reference the non-brief name (e.g. foo_type_u). This causes a build
failure when actually trying to compile the generated .xdr.c, like so:

    foo.xdr.c:809:39: error: 'foo_type' has no member named 'foo_type_u'
        if (!xdr_bytes(xdrs, (char **)&objp->foo_type_u.xxx, &__len, FOO_MAX)) {
                                           ^
    foo.xdr.c:812:11: error: 'foo_type' has no member named 'foo_type_u'
        *(&objp->foo_type_u.xxx) = __len;

This happens because the portion of emit_union() that generates the
XDR code for the default arm wasn't updated to use a different
formatting string when 'brief_flag' is set, like the rest of
emit_union.

To fix this, just check for brief_flag and use 'briefformat'
accordingly, like the other code that checks for brief_flag.

Currently nothing in the tree uses the default arm of RPC-L unions
with 'rxgen -b', but external callers could, or our future code may do
so.

Change-Id: Ifcebfc48a3a64c68fee12ba0d177ae19b0956c58
Reviewed-on: https://gerrit.openafs.org/14107
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Cheyenne Wills <cwills@sinenomine.net>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>
---

diff --git a/src/rxgen/rpc_cout.c b/src/rxgen/rpc_cout.c
index b0a686f..5c17a90 100644
--- a/src/rxgen/rpc_cout.c
+++ b/src/rxgen/rpc_cout.c
@@ -368,7 +368,10 @@ emit_union(definition * def)
 	    object =
 		alloc(strlen(def->def_name) + strlen(format) +
 		      strlen(dflt->name) + 1);
-	    s_print(object, format, def->def_name, dflt->name);
+	    if (brief_flag)
+		s_print(object, briefformat, dflt->name);
+	    else
+		s_print(object, format, def->def_name, dflt->name);
 	    print_ifstat(2, dflt->prefix, dflt->type, dflt->rel,
 			 dflt->array_max, object, dflt->name);
 	    free(object);