getcwd: enhance tests

The existing getcwd was weak, and only tested things guaranteed
by the new getcwd-lgpl.  Move those tests into a new file and
strengthen them slightly (such as guaranteeing the ERANGE error
for a non-zero but too-small size).  Then copy the m4 tests
for PATH_MAX failures into the GPL getcwd tests, to prove that
our replacement really is fixing the things that cause us to
reject the system getcwd as non-robust.

* tests/test-getcwd-lgpl.c: New file, taken from...
* tests/test-getcwd.c: ...old contents.  Rewrite this file to
repeat long path stress tests from m4 probe.
* modules/getcwd-lgpl-tests: New module.
* modules/getcwd-tests (Depends-on): Depend on lgpl tests.
* m4/getcwd-abort-bug.m4: Update comment.
* m4/getcwd-path-max.m4: Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>

2 files changed, 16 insertions, 2 deletions

diff --git a/modules/getcwd-lgpl-tests b/modules/getcwd-lgpl-tests
new file mode 100644
index 0000000000..07fdf73d5c
--- /dev/null
+++ b/modules/getcwd-lgpl-tests
@@ -0,0 +1,12 @@
+Files:
+tests/test-getcwd-lgpl.c
+tests/signature.h
+tests/macros.h
+
+Depends-on:
+
+configure.ac:
+
+Makefile.am:
+TESTS += test-getcwd-lgpl
+check_PROGRAMS += test-getcwd-lgpl
diff --git a/modules/getcwd-tests b/modules/getcwd-tests
index 016961fc71..2187acc75f 100644
--- a/modules/getcwd-tests
+++ b/modules/getcwd-tests
@@ -1,9 +1,11 @@
 Files:
 tests/test-getcwd.c
-tests/signature.h
-tests/macros.h
 
 Depends-on:
+errno
+fcntl-h
+getcwd-lgpl
+sys_stat
 
 configure.ac: