This patch allows us to skip tests that require PTRACE_ATTACH in situations
where PTRACE_ATTACH is only allowed when CAP_SYS_PTRACE is held (i.e., for
root, by default.)

Reported at <https://bugzilla.redhat.com/show_bug.cgi?id=1210966>.

--- elfutils-0.161/tests/run-deleted.sh	2015-04-11 16:38:33.028556235 +0200
+++ elfutils-0.161/tests/run-deleted.sh	2015-04-11 16:46:15.012442185 +0200
@@ -17,6 +17,15 @@
 
 . $srcdir/backtrace-subr.sh
 
+# Check whether the Yama policy allows us to use PTRACE_ATTACH.
+if [ -f /proc/sys/kernel/yama/ptrace_scope ]
+then
+    if [ `cat /proc/sys/kernel/yama/ptrace_scope` -ne 0 ]
+    then
+	exit 77
+    fi
+fi
+
 tempfiles deleted deleted-lib.so
 cp -p ${abs_builddir}/deleted ${abs_builddir}/deleted-lib.so .
 
--- elfutils-0.161/tests/vdsosyms.c	2015-04-11 16:40:20.633461110 +0200
+++ elfutils-0.161/tests/vdsosyms.c	2015-04-11 16:45:06.611866677 +0200
@@ -23,6 +23,8 @@
 #include <stdio.h>
 #include <string.h>
 #include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
 #include <unistd.h>
 #include ELFUTILS_HEADER(dwfl)
 
@@ -68,6 +70,7 @@ module_callback (Dwfl_Module *mod, void
 int
 main (int argc __attribute__ ((unused)), char **argv __attribute__ ((unused)))
 {
+  static const char ptrace_scope_file[] = "/proc/sys/kernel/yama/ptrace_scope";
   static char *debuginfo_path;
   static const Dwfl_Callbacks proc_callbacks =
     {
@@ -76,6 +79,20 @@ main (int argc __attribute__ ((unused)),
 
       .find_elf = dwfl_linux_proc_find_elf,
     };
+
+  /* Check whether the Yama policy allows us to use PTRACE_ATTACH.  */
+  int ptrace_scope = open (ptrace_scope_file, O_RDONLY);
+  if (ptrace_scope >= 0)
+    {
+      char buf[10];
+      int count = read (ptrace_scope, buf, sizeof buf);
+      assert (count > 0);
+      if (buf[0] != '0')
+	/* We're not allowed, so skip this test.  */
+	return 77;
+      close (ptrace_scope);
+    }
+
   Dwfl *dwfl = dwfl_begin (&proc_callbacks);
   if (dwfl == NULL)
     error (2, 0, "dwfl_begin: %s", dwfl_errmsg (-1));
759b198042ced866efc423dd4b97'>root</a>/<a href='/guix/log/tests?id=ca3adf26072c759b198042ced866efc423dd4b97'>tests</a>/<a href='/guix/log/tests/lzlib.scm?id=ca3adf26072c759b198042ced866efc423dd4b97'>lzlib.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/lzlib.scm?id=ca3adf26072c759b198042ced866efc423dd4b97&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-01-16 23:14:05 +0100'>2020-01-16</span></td><td><a href='/guix/commit/tests/lzlib.scm?id=3597c0396b9bd6440c02462107c743c6aeb29672'>lzlib: Define 'dictionary-size+match-length-limit'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/lzlib.scm (%compression-levels): Splice the rest of each element.
(dictionary-size+match-length-limit): New procedure.
(make-lzip-output-port, make-lzip-input-port/compressed): Use it.
* tests/lzlib.scm ("Bytevector of size relative to Lzip internal buffers (2 * dictionary)"):
Use 'dictionary-size+match-length-limit' instead of 'assoc-ref'.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-12-01 16:51:40 +0100'>2019-12-01</span></td><td><a href='/guix/commit/tests/lzlib.scm?id=2c5dd47ceffd61d155e64dcb1764ffaea0ffd546'>tests: lzlib: Do not fail if lzlib in not available.</a><span class='msg-avail'>...<span class='msg-tooltip'>* tests/lzlib.scm: Use test-assert* for all test cases, so that there are no
failures if lzlib is unavailable.
</span></span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2019-05-27 22:47:24 +0200'>2019-05-27</span></td><td><a href='/guix/commit/tests/lzlib.scm?id=2a991f3ae4823730395c7970d83159e93d5f5fe2'>lzlib: Add 'make-lzip-input-port/compressed'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/lzlib.scm (lzwrite!, make-lzip-input-port/compressed): New
procedures.
* tests/lzlib.scm ("make-lzip-input-port/compressed"): New test.
* guix/tests.scm (%seed): Export.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-05-06 23:21:33 +0200'>2019-05-06</span></td><td><a href='/guix/commit/tests/lzlib.scm?id=fea338c6ca1922097fa233be85f424c152a4f507'>Add (guix lzlib).</a><span class='msg-avail'>...<span class='msg-tooltip'>* guix/lzlib.scm, tests/lzlib.scm: New files.
* Makefile.am (MODULES): Add guix/lzlib.scm.
(SCM_TESTS): Add tests/lzlib.scm.
* m4/guix.m4 (GUIX_LIBLZ_LIBDIR): New macro.
* configure.ac (LIBLZ_LIBDIR): Use it.  Define and substitute
'LIBLZ'.
* guix/config.scm.in (%liblz): New variable.
* guix/self.scm (make-config.scm): Add TODO comment.

Co-authored-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Pierre Neidhardt</td></tr>