lib/xref: record log message format args

Apparently you can do `#__VA_ARGS__` and it actually does something
sensible, so here we go recording the format parameters for log messages
into the xref.

This allows some more checking in xrelfo.py, e.g. hints to use `%pFX`
and co.

Signed-off-by: David Lamparter <equinox@diac24.net>

2 files changed, 49 insertions, 16 deletions

diff --git a/python/xrefstructs.json b/python/xrefstructs.json
index 537afb87e..e62c351bc 100644
--- a/python/xrefstructs.json
+++ b/python/xrefstructs.json
@@ -126,6 +126,12 @@
         "offset": 44,
         "size": 4,
         "type": "uint32_t"
+      },
+      {
+        "name": "args",
+        "offset": 48,
+        "size": 8,
+        "type": "const char  *"
       }
     ]
   },
diff --git a/python/xrelfo.py b/python/xrelfo.py
index b726d2895..0ecd00857 100644
--- a/python/xrelfo.py
+++ b/python/xrelfo.py
@@ -112,35 +112,60 @@ class XrefLogmsg(ELFDissectStruct, XrelfoJson):
     struct = 'xref_logmsg'
 
     def _warn_fmt(self, text):
-        yield ((self.xref.file, self.xref.line), '%s:%d: %s (in %s())\n' % (self.xref.file, self.xref.line, text, self.xref.func))
+        lines = text.split('\n')
+        yield ((self.xref.file, self.xref.line), '%s:%d: %s (in %s())%s\n' % (self.xref.file, self.xref.line, lines[0], self.xref.func, ''.join(['\n' + l for l in lines[1:]])))
 
-    regexes = [
+    fmt_regexes = [
         (re.compile(r'([\n\t]+)'), 'error: log message contains tab or newline'),
     #    (re.compile(r'^(\s+)'),   'warning: log message starts with whitespace'),
         (re.compile(r'^((?:warn(?:ing)?|error):\s*)', re.I), 'warning: log message starts with severity'),
     ]
+    arg_regexes = [
+    # the (?<![\?:] ) avoids warning for x ? inet_ntop(...) : "(bla)"
+        (re.compile(r'((?<![\?:] )inet_ntop\s*\(\s*(?:[AP]F_INET|2)\s*,)'),   'cleanup: replace inet_ntop(AF_INET, ...) with %pI4',  lambda s: True),
+        (re.compile(r'((?<![\?:] )inet_ntop\s*\(\s*(?:[AP]F_INET6|10)\s*,)'), 'cleanup: replace inet_ntop(AF_INET6, ...) with %pI6', lambda s: True),
+        (re.compile(r'((?<![\?:] )inet_ntoa)'),                               'cleanup: replace inet_ntoa(...) with %pI4',           lambda s: True),
+        (re.compile(r'((?<![\?:] )ipaddr2str)'),                              'cleanup: replace ipaddr2str(...) with %pIA',          lambda s: True),
+        (re.compile(r'((?<![\?:] )prefix2str)'),                              'cleanup: replace prefix2str(...) with %pFX',          lambda s: True),
+        (re.compile(r'((?<![\?:] )prefix_mac2str)'),                          'cleanup: replace prefix_mac2str(...) with %pEA',      lambda s: True),
+        (re.compile(r'((?<![\?:] )sockunion2str)'),                           'cleanup: replace sockunion2str(...) with %pSU',       lambda s: True),
+
+    #   (re.compile(r'^(\s*__(?:func|FUNCTION|PRETTY_FUNCTION)__\s*)'), 'error: debug message starts with __func__', lambda s: (s.priority & 7 == 7) ),
+    ]
 
     def check(self, wopt):
+        def fmt_msg(rex, itext):
+            if sys.stderr.isatty():
+                items = rex.split(itext)
+                out = []
+                for i, text in enumerate(items):
+                    if (i % 2) == 1:
+                        out.append('\033[41;37;1m%s\033[m' % repr(text)[1:-1])
+                    else:
+                        out.append(repr(text)[1:-1])
+
+                excerpt = ''.join(out)
+            else:
+                excerpt = repr(itext)[1:-1]
+            return excerpt
+
         if wopt.Wlog_format:
-            for rex, msg in self.regexes:
+            for rex, msg in self.fmt_regexes:
                 if not rex.search(self.fmtstring):
                     continue
 
-                if sys.stderr.isatty():
-                    items = rex.split(self.fmtstring)
-                    out = []
-                    for i, text in enumerate(items):
-                        if (i % 2) == 1:
-                            out.append('\033[41;37;1m%s\033[m' % repr(text)[1:-1])
-                        else:
-                            out.append(repr(text)[1:-1])
-
-                    excerpt = ''.join(out)
+                excerpt = fmt_msg(rex, self.fmtstring)
+                yield from self._warn_fmt('%s: "%s"' % (msg, excerpt))
 
-                else:
-                    excerpt = repr(self.fmtstring)[1:-1]
+        if wopt.Wlog_args:
+            for rex, msg, cond in self.arg_regexes:
+                if not cond(self):
+                    continue
+                if not rex.search(self.args):
+                    continue
 
-                yield from self._warn_fmt('%s: "%s"' % (msg, excerpt))
+                excerpt = fmt_msg(rex, self.args)
+                yield from self._warn_fmt('%s:\n\t"%s",\n\t%s' % (msg, repr(self.fmtstring)[1:-1], excerpt))
 
     def dump(self):
         print('%-60s %s%s %-25s [EC %d] %s' % (
@@ -154,6 +179,7 @@ class XrefLogmsg(ELFDissectStruct, XrelfoJson):
         if self.ec != 0:
             jsobj['ec'] = self.ec
         jsobj['fmtstring'] = self.fmtstring
+        jsobj['args'] = self.args
         jsobj['priority'] = self.priority & 7
         jsobj['type'] = 'logmsg'
         jsobj['binary'] = self._elfsect._elfwrap.orig_filename
@@ -330,6 +356,7 @@ def main():
     argp.add_argument('-o', dest='output', type=str, help='write JSON output')
     argp.add_argument('--out-by-file',     type=str, help='write by-file JSON output')
     argp.add_argument('-Wlog-format',      action='store_const', const=True)
+    argp.add_argument('-Wlog-args',        action='store_const', const=True)
     argp.add_argument('--profile',         action='store_const', const=True)
     argp.add_argument('binaries', metavar='BINARY', nargs='+', type=str, help='files to read (ELF files or libtool objects)')
     args = argp.parse_args()