[src/trunk]: src/lib/librumpuser Support binaries which use DT_GNU_HASH inste...

[pooka <pooka%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/2e6d54ed9006
branches:  trunk
changeset: 783225:2e6d54ed9006
user:      pooka <pooka%NetBSD.org@localhost>
date:      Tue Dec 11 21:16:22 2012 +0000

description:
Support binaries which use DT_GNU_HASH instead of DT_HASH.

diffstat:

 lib/librumpuser/rumpuser_dl.c |  51 +++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 49 insertions(+), 2 deletions(-)

diffs (72 lines):

diff -r a9ff3cc9a1cc -r 2e6d54ed9006 lib/librumpuser/rumpuser_dl.c
--- a/lib/librumpuser/rumpuser_dl.c     Tue Dec 11 19:29:29 2012 +0000
+++ b/lib/librumpuser/rumpuser_dl.c     Tue Dec 11 21:16:22 2012 +0000
@@ -1,4 +1,4 @@
-/*      $NetBSD: rumpuser_dl.c,v 1.10 2012/11/26 17:55:11 pooka Exp $  */
+/*      $NetBSD: rumpuser_dl.c,v 1.11 2012/12/11 21:16:22 pooka Exp $  */
 
 /*
  * Copyright (c) 2009 Antti Kantee.  All Rights Reserved.
@@ -33,7 +33,7 @@
 #include "rumpuser_port.h"
 
 #if !defined(lint)
-__RCSID("$NetBSD: rumpuser_dl.c,v 1.10 2012/11/26 17:55:11 pooka Exp $");
+__RCSID("$NetBSD: rumpuser_dl.c,v 1.11 2012/12/11 21:16:22 pooka Exp $");
 #endif /* !lint */
 
 #include <sys/types.h>
@@ -213,6 +213,53 @@
                        hashtab = (Elf_Symindx *)adjptr(map, edptr);
                        cursymcount = hashtab[1];
                        break;
+#ifdef DT_GNU_HASH
+               /*
+                * DT_GNU_HASH is a bit more complicated than DT_HASH
+                * in this regard since apparently there is no field
+                * telling us the total symbol count.  Instead, we look
+                * for the last valid hash bucket and add its chain lenght
+                * to the bucket's base index.
+                */
+               case DT_GNU_HASH: {
+                       Elf32_Word nbuck, symndx, maskwords, maxchain = 0;
+                       Elf32_Word *gnuhash, *buckets, *ptr;
+                       int bi;
+
+                       DYNn_GETMEMBER(ed_base, i, d_un.d_ptr, edptr);
+                       gnuhash = (Elf32_Word *)adjptr(map, edptr);
+
+                       nbuck = gnuhash[0];
+                       symndx = gnuhash[1];
+                       maskwords = gnuhash[2];
+
+                       /*
+                        * First, find the last valid bucket and grab its index
+                        */
+                       if (eident == ELFCLASS64)
+                               maskwords *= 2; /* sizeof(*buckets) == 4 */
+                       buckets = gnuhash + 4 + maskwords;
+                       for (bi = nbuck-1; bi >= 0; bi--) {
+                               if (buckets[bi] != 0) {
+                                       maxchain = buckets[bi];
+                                       break;
+                               }
+                       }
+                       if (maxchain == 0 || maxchain < symndx)
+                               break;
+
+                       /*
+                        * Then, traverse the last chain and count symbols.
+                        */
+
+                       cursymcount = maxchain;
+                       ptr = buckets + nbuck + (maxchain - symndx);
+                       do {
+                               cursymcount++;
+                       } while ((*ptr++ & 1) == 0);
+               }       
+                       break;
+#endif
                case DT_SYMENT:
                        DYNn_GETMEMBER(ed_base, i, d_un.d_val, edval);
                        assert(edval == SYM_GETSIZE());