Add pretty-printer for errno.zack/errno-prettyprint

This patch adds the actual pretty-printer for errno.  I could have
used Python's built-in errno module to get the symbolic names for the
constants, but it seemed better to do something entirely under our
control, so there's a .pysym file generated from errnos.texi, with a
hook that allows the Hurd to add additional constants.  Then a .py
module is generated from that plus errno.h in the usual manner; many
thanks to the authors of the .pysym mechanism.

There is also a test which verifies that the .py file (not the .pysym
file) covers all of the constants defined in errno.h.

hurd-add-errno-constants.awk has been manually tested, but the
makefile logic that runs it has not been tested.

	* stdlib/errno-printer.py: New pretty-printer.
	* stdlib/test-errno-constants.py: New special test.
	* stdlib/test-errno-printer.c, stdlib/test-errno-printer.py:
	New pretty-printer test.
	* stdlib/make-errno-constants.awk: New script to generate the
	.pysym file needed by errno-printer.py.
	* stdlib/Makefile: Install, run, and test all of the above, as
	appropriate.

	* sysdeps/mach/hurd/hurd-add-errno-constants.awk: New script to
	add Mach/Hurd-specific errno constants to the .pysym file used by
	stdlib/errno-printer.py.
	* sysdeps/mach/hurd/Makefile: Hook hurd-add-errno-constants.awk
	into the generation of that .pysym file.

1 files changed, 38 insertions, 0 deletions

diff --git a/stdlib/Makefile b/stdlib/Makefile
index 0314d5926b..31025465cb 100644
--- a/stdlib/Makefile
+++ b/stdlib/Makefile
@@ -149,6 +149,34 @@ ifeq ($(run-built-tests),yes)
 tests-special += $(objpfx)tst-fmtmsg.out
 endif
 
+ifdef PYTHON
+# Pretty-printer for errno.  The .pysym file is itself generated from
+# errnos.texi, and can be augmented by sysdeps Makefiles, primarily for
+# the sake of the Hurd, which has a bunch of extra error constants.
+pretty-printers := errno-printer.py
+tests-printers := test-errno-printer
+gen-py-const-headers := errno_constants.pysym
+vpath %.pysym $(objpfx)
+
+define sysd-add-errno-constants
+:
+endef
+$(objpfx)errno_constants.pysym: make-errno-constants.awk \
+				$(..)manual/errno.texi
+	($(AWK) -f make-errno-constants.awk $(..)manual/errno.texi; \
+	$(sysd-add-errno-constants)) > $@T
+	mv -f $@T $@
+
+# We must specify both CFLAGS and CPPFLAGS to override any
+# compiler options the user might have provided that conflict
+# with what we need e.g. user specifies CPPFLAGS with -O2 and
+# we need -O0.
+CFLAGS-test-errno-printer.c := $(CFLAGS-printers-tests)
+CPPFLAGS-test-errno-printer.c := $(CFLAGS-printers-tests)
+
+tests-special += $(objpfx)test-errno-constants.out
+endif
+
 include ../Rules
 
 ifeq ($(run-built-tests),yes)
@@ -220,3 +248,13 @@ $(objpfx)tst-setcontext3.out: tst-setcontext3.sh $(objpfx)tst-setcontext3
 	$(evaluate-test)
 
 $(objpfx)tst-makecontext: $(libdl)
+
+# Note: errno_constants.py depends on errno.h and everything it
+# includes, as well as on errno_constants.pysym, so we don't need to
+# specify that this test also depends on both.
+$(objpfx)test-errno-constants.out: \
+		test-errno-constants.py $(objpfx)errno_constants.py
+	$(PYTHON) $< $(objpfx) $(CC) $(CFLAGS) $(CPPFLAGS) > $@; \
+	$(evaluate-test)
+
+libof-test-errno-constants = testsuite