Fix hardcoded /tmp paths in testing (bug 13888).

As noted in bug 13888, and as I noted previously in
<https://sourceware.org/ml/libc-alpha/2000-10/msg00111.html>, various
tests used hardcoded paths in /tmp, so posing issues for simultaneous
test runs from different build directories.

This patch fixes such uses of hardcoded file names to put them in the
build directory instead (in the case of stdio-common/bug5 the file
names are changed as well, to avoid a conflict with the name bug5.out
also used for the automatic test output redirection).  It also fixes
test-installation.pl likewise (that was using filenames with $$ in
them rather than strictly hardcoded names, but that's still not good
practice for temporary file naming).

Note that my list of files changed is not identical to that in bug
13888.  I added tst-spawn3.c and test-installation.pl, and removed
some tests that seem to me (now) to create temporary files securely
(simply using /tmp is not itself a problem if the temporary files are
handled properly with mkstemp; I haven't checked whether those tests
used to do things insecurely).  conformtest is not changed because the
makefiles always pass a --tmpdir option so the /tmp default is
irrelevant, and for the same reason there is no actual problem with
nptl/tst-umask1.c because again the makefiles always override the
default.

nptl/sockperf.c is ignored because there is no code to run it;
probably that file should actually be removed.

Some tests use the mktemp function, but I think they all use it in a
way that *is* secure (for generating names for directories / sockets /
fifos / symlinks, where the operation using the name will not follow
symlinks and so there is no potential for a symlink attack on the
account running the testsuite).

Some tests use the tmpnam function to generate temporary file names.
This is in principle insecure, but not addressed by this patch (I
consider it a separate issue from the fully hardcoded paths).

Tested for x86_64.

	[BZ #13888]
	* posix/Makefile (CFLAGS-tst-spawn3.c): New variable.
	* posix/tst-spawn3.c (do_test): Put tst-spwan3.pid in OBJPFX, not
	/tmp.
	* scripts/test-installation.pl: Put temporary files in build
	directory, not /tmp.
	* stdio-common/Makefile (CFLAGS-bug3.c): New variable.
	(CFLAGS-bug4.c): Likewise.
	(CFLAGS-bug5.c): Likewise.
	(CFLAGS-test-fseek.c): Likewise.
	(CFLAGS-test-popen.c): Likewise.
	(CFLAGS-test_rdwr.c): Likewise.
	* stdio-common/bug3.c (main): Put temporary file in OBJPFX, not
	/tmp.
	* stdio-common/bug4.c (main): Likewise.
	* stdio-common/bug5.c (main): Likewise.
	* stdio-common/test-fseek.c (TESTFILE): Likewise.
	* stdio-common/test-popen.c (do_test): Likewise.
	* stdio-common/test_rdwr.c (main): Likewise.

2 files changed, 3 insertions, 2 deletions

diff --git a/posix/Makefile b/posix/Makefile
index 4a9a1b57b8..989e42e1f8 100644
--- a/posix/Makefile
+++ b/posix/Makefile
@@ -256,6 +256,7 @@ tst-pcre-ARGS = PCRE.tests
 tst-boost-ARGS = BOOST.tests
 bug-glob1-ARGS = "$(objpfx)"
 tst-execvp3-ARGS = --test-dir=$(objpfx)
+CFLAGS-tst-spawn3.c += -DOBJPFX=\"$(objpfx)\"
 
 testcases.h: TESTS TESTS2C.sed
 	LC_ALL=C sed -f TESTS2C.sed < $< > $@T
diff --git a/posix/tst-spawn3.c b/posix/tst-spawn3.c
index dc6bed52a4..b60a783dd4 100644
--- a/posix/tst-spawn3.c
+++ b/posix/tst-spawn3.c
@@ -82,8 +82,8 @@ do_test (void)
   if (posix_spawn_file_actions_init (&a) != 0)
     FAIL_EXIT1 ("posix_spawn_file_actions_init");
 
-  /* Executes a /bin/sh echo $$ 2>&1 > /tmp/tst-spawn3.pid .  */
-  const char pidfile[] = "/tmp/tst-spawn3.pid";
+  /* Executes a /bin/sh echo $$ 2>&1 > ${objpfx}tst-spawn3.pid .  */
+  const char pidfile[] = OBJPFX "tst-spawn3.pid";
   if (posix_spawn_file_actions_addopen (&a, STDOUT_FILENO, pidfile, O_WRONLY |
 					O_CREAT | O_TRUNC, 0644) != 0)
     FAIL_EXIT1 ("posix_spawn_file_actions_addopen");