*: make sure `config.h` or `zebra.h` is first

`config.h` has all the defines from autoconf, which may include things
that switch behavior of other included headers (e.g. _GNU_SOURCE
enabling prototypes for additional functions.)

So, the first include in any `.c` file must be either `config.h` (with
the appropriate guard) or `zebra.h` (which includes `config.h` first
thing.)

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>

1 files changed, 76 insertions, 16 deletions

diff --git a/python/firstheader.py b/python/firstheader.py
index bf50f33a33..892e9da8d6 100644
--- a/python/firstheader.py
+++ b/python/firstheader.py
@@ -1,30 +1,90 @@
-#
 # check that the first header included in C files is either
 # zebra.h or config.h
 #
+# Copyright (C) 2020  David Lamparter for NetDEF, Inc.
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by the Free
+# Software Foundation; either version 2 of the License, or (at your option)
+# any later version.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; see the file COPYING; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 
-import sys, os, re, subprocess
+import sys
+import os
+import re
+import subprocess
+import argparse
+
+argp = argparse.ArgumentParser(description="include fixer")
+argp.add_argument("--autofix", action="store_const", const=True)
+argp.add_argument("--warn-empty", action="store_const", const=True)
+argp.add_argument("--pipe", action="store_const", const=True)
 
 include_re = re.compile('^#\s*include\s+["<]([^ ">]+)[">]', re.M)
 
-errors = 0
+ignore = [
+    lambda fn: fn.startswith("tools/"),
+    lambda fn: fn
+    in [
+        "lib/elf_py.c",
+    ],
+]
+
+
+def run(args):
+    out = []
+
+    files = subprocess.check_output(["git", "ls-files"]).decode("ASCII")
+    for fn in files.splitlines():
+        if not fn.endswith(".c"):
+            continue
+        if max([i(fn) for i in ignore]):
+            continue
+
+        with open(fn, "r") as fd:
+            data = fd.read()
 
-files = subprocess.check_output(["git", "ls-files"]).decode("ASCII")
-for fn in files.splitlines():
-    if not fn.endswith(".c"):
-        continue
-    if fn.startswith("tools/"):
-        continue
-    with open(fn, "r") as fd:
-        data = fd.read()
         m = include_re.search(data)
         if m is None:
-            # sys.stderr.write('no #include in %s?\n' % (fn))
+            if args.warn_empty:
+                sys.stderr.write("no #include in %s?\n" % (fn))
             continue
         if m.group(1) in ["config.h", "zebra.h", "lib/zebra.h"]:
             continue
-        sys.stderr.write("%s: %s\n" % (fn, m.group(0)))
-        errors += 1
 
-if errors:
-    sys.exit(1)
+        if args.autofix:
+            sys.stderr.write("%s: %s - fixing\n" % (fn, m.group(0)))
+            if fn.startswith("pceplib/"):
+                insert = '#ifdef HAVE_CONFIG_H\n#include "config.h"\n#endif\n\n'
+            else:
+                insert = "#include <zebra.h>\n\n"
+
+            pos = m.span()[0]
+
+            data = data[:pos] + insert + data[pos:]
+            with open(fn + ".new", "w") as fd:
+                fd.write(data)
+            os.rename(fn + ".new", fn)
+        else:
+            sys.stderr.write("%s: %s\n" % (fn, m.group(0)))
+            out.append(fn)
+
+    if len(out):
+        if args.pipe:
+            # for "vim `firstheader.py`"
+            print("\n".join(out))
+        return 1
+    return 0
+
+
+if __name__ == "__main__":
+    args = argp.parse_args()
+    sys.exit(run(args))