[patch] Adjust AT_EXECFN on explicit loader invocation

[Paul Pluzhnikov]

On Mon, Nov 18, 2013 at 1:48 PM, Ondřej Bílka <neleai@seznam.cz> wrote:

> Is there any reason not use getauxval(AT_EXECFN) for test?

None that I know of. Thanks for the hint. Updated patch attached.

The getauxval() will allow me to get rid of a local patch that exposed
the same info. Woo-hoo!

-- 
Paul Pluzhnikov


2013-11-13  Paul Pluzhnikov  <ppluzhnikov@google.com>

        * elf/Makefile (tst-auxv): New test.
        * elf/tst-auxv.c: New
        * elf/rtld.c (dl_main): Adjust AT_EXECFN
-------------- next part --------------
diff --git a/elf/Makefile b/elf/Makefile
index 27d249b..c6626e1 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -119,7 +119,8 @@ $(inst_auditdir)/sotruss-lib.so: $(objpfx)sotruss-lib.so $(+force)
 endif
 
 tests = tst-tls1 tst-tls2 tst-tls9 tst-leaks1 \
-	tst-array1 tst-array2 tst-array3 tst-array4 tst-array5
+	tst-array1 tst-array2 tst-array3 tst-array4 tst-array5 \
+	tst-auxv
 tests-static = tst-tls1-static tst-tls2-static tst-stackguard1-static \
 	       tst-leaks1-static tst-array1-static tst-array5-static \
 	       tst-ptrguard1-static
diff --git a/elf/rtld.c b/elf/rtld.c
index c5a6538..3d207a3 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -1118,6 +1118,9 @@ of this helper program; chances are you did not intend to run this program.\n\
 	  case AT_ENTRY:
 	    av->a_un.a_val = *user_entry;
 	    break;
+	  case AT_EXECFN:
+	    av->a_un.a_val = (uintptr_t) _dl_argv[0];
+	    break;
 	  }
 #endif
     }
diff --git a/elf/tst-auxv.c b/elf/tst-auxv.c
new file mode 100644
index 0000000..af29edd
--- /dev/null
+++ b/elf/tst-auxv.c
@@ -0,0 +1,45 @@
+/* Copyright (C) 2013 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <elf.h>
+#include <link.h>
+#include <string.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <misc/sys/auxv.h>
+
+static int
+do_test (int argc, char *argv[])
+{
+  const char *execfn = (const char *) getauxval (AT_EXECFN);
+
+  if (execfn == NULL)
+    {
+      printf ("No AT_EXECFN found, test skipped\n");
+      return 0;
+    }
+
+  if (strcmp (argv[0], execfn) != 0)
+    {
+      printf ("Mismatch: arv[0]: %s vs. AT_EXECFN: %s\n", argv[0], execfn);
+      return 1;
+    }
+
+  return 0;
+}
+
+#include "../test-skeleton.c"