support: Introduce new subdirectory for test infrastructure

The new test driver in <support/test-driver.c> has feature parity with
the old one.  The main difference is that its hooking mechanism is
based on functions and function pointers instead of macros.  This
commit also implements a new environment variable, TEST_COREDUMPS,
which disables the code which disables coredumps (that is, it enables
them if the invocation environment has not disabled them).

<test-skeleton.c> defines wrapper functions so that it is possible to
use existing macros with the new-style hook functionality.

This commit changes only a few test cases to the new test driver, to
make sure that it works as expected.

1 files changed, 2 insertions, 6 deletions

diff --git a/libio/tst-fseek.c b/libio/tst-fseek.c
index 9bb0d7f707..1a81740ed9 100644
--- a/libio/tst-fseek.c
+++ b/libio/tst-fseek.c
@@ -24,9 +24,7 @@
 #include <unistd.h>
 #include <string.h>
 
-/* Defined in test-skeleton.c.  */
-static int create_temp_file (const char *base, char **filename);
-
+#include <support/temp_file.h>
 
 static int
 do_seek_end (FILE *fp)
@@ -168,6 +166,4 @@ do_test (void)
   return ret;
 }
 
-
-#define TEST_FUNCTION do_test ()
-#include "../test-skeleton.c"
+#include <support/test-driver.c>