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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 17:54:12 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 17:54:12 +0000
commitb527294153be3b79563c82c66102adc0004736c0 (patch)
tree9b423a224848441885190b5ea7cf0feb23510c9d /doc/devel/variadic_debug/07-shortcut.cocci
parentInitial commit. (diff)
downloadopenldap-b527294153be3b79563c82c66102adc0004736c0.tar.xz
openldap-b527294153be3b79563c82c66102adc0004736c0.zip
Adding upstream version 2.6.7+dfsg.upstream/2.6.7+dfsg
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'doc/devel/variadic_debug/07-shortcut.cocci')
-rw-r--r--doc/devel/variadic_debug/07-shortcut.cocci216
1 files changed, 216 insertions, 0 deletions
diff --git a/doc/devel/variadic_debug/07-shortcut.cocci b/doc/devel/variadic_debug/07-shortcut.cocci
new file mode 100644
index 0000000..99b3b55
--- /dev/null
+++ b/doc/devel/variadic_debug/07-shortcut.cocci
@@ -0,0 +1,216 @@
+// Splice string `s` into the format string `fmtstring` replacing the
+// %-parameter at position `pos`
+@initialize:python@
+@@
+
+# regex from https://stackoverflow.com/questions/30011379/how-can-i-parse-a-c-format-string-in-python
+import re
+fmtstring = '''\
+( # start of capture group 1
+% # literal "%"
+(?: # first option
+(?:[-+0 #]{0,5}) # optional flags
+(?:\d+|\*)? # width
+(?:\.(?:\d+|\*))? # precision
+(?:h|l|ll|w|I|I32|I64)? # size
+[cCdiouxXeEfgGaAnpsSZ] # type
+) | # OR
+%%) # literal "%%"
+'''
+
+regex = re.compile(fmtstring, re.X)
+
+def parse_format(f):
+ return tuple((m.span(), m.group()) for m in
+ regex.finditer(f))
+
+def insert_at_pos(fmt, s, pos):
+ formats = parse_format(fmt)
+ span, format = formats[pos]
+ acc = fmt[:span[0]]
+ if s.startswith('"'):
+ acc += s[1:]
+ else:
+ acc += '" '
+ acc += s
+ if acc.endswith('"'):
+ acc = acc[:-1] + fmt[span[1]:]
+ else:
+ acc += ' "'
+ acc += fmt[span[1]:]
+ return acc
+
+// rest of the file implements the same as 09-merge.cocci
+// The main difference is that we only match on snprintf and Debug that are
+// directly adjacent, not based on control flow information which trips
+// coccinelle's model-checker
+@shortcut@
+identifier buf;
+expression E, L;
+expression list args_before, args, args_after;
+expression format1, format2;
+position p1, p2;
+@@
+
+snprintf@p1( buf, E, format1, args );
+Debug@p2( L, format2, args_before, buf, args_after );
+
+// use insert_at_pos above to construct the new format-string
+@script:python shortcut_process@
+format1 << shortcut.format1;
+format2 << shortcut.format2;
+args_before << shortcut.args_before;
+merged;
+@@
+
+pos = len(args_before.elements)
+coccinelle.merged = insert_at_pos(format2, format1, pos)
+
+@shortcut_replace@
+position shortcut.p1, shortcut.p2;
+identifier shortcut_process.merged;
+
+identifier buf;
+expression E, L;
+expression list args_before, args, args_after;
+expression format1, format2;
+@@
+
+-snprintf@p1( buf, E, format1, args );
+-Debug@p2( L, format2, args_before, buf, args_after );
++Debug( L, merged, args_before, args, args_after );
+
+@shortcut_locked@
+identifier buf;
+expression E, L, lock;
+expression list args_before, args, args_after;
+expression format1, format2;
+position p1, p2;
+@@
+
+ldap_pvt_thread_mutex_lock(lock);
+snprintf@p1( buf, E, format1, args );
+ldap_pvt_thread_mutex_unlock(lock);
+Debug@p2( L, format2, args_before, buf, args_after );
+
+// use insert_at_pos above to construct the new format-string
+@script:python shortcut_locked_process@
+format1 << shortcut_locked.format1;
+format2 << shortcut_locked.format2;
+args_before << shortcut_locked.args_before;
+merged;
+@@
+
+pos = len(args_before.elements)
+coccinelle.merged = insert_at_pos(format2, format1, pos)
+
+@shortcut_locked_replace@
+position shortcut_locked.p1, shortcut_locked.p2;
+identifier shortcut_locked_process.merged;
+
+identifier buf;
+expression E, L, lock;
+expression list args_before, args, args_after;
+expression format1, format2;
+@@
+
+ldap_pvt_thread_mutex_lock(lock);
+-snprintf@p1( buf, E, format1, args );
++Debug( L, merged, args_before, args, args_after );
+ldap_pvt_thread_mutex_unlock(lock);
+-Debug@p2( L, format2, args_before, buf, args_after );
+
+// so long as we don't reference 'buf' afterwards, no need to keep it defined.
+// A lot of pattern-matching is spelled out explicitly to work around the fact
+// that the state space doesn't get compressed otherwise.
+@@
+type T;
+identifier buf, id;
+expression E, lock;
+initializer I;
+@@
+{
+-\( T buf = I; \| T buf; \)
+(
+ ldap_pvt_thread_mutex_lock(lock);
+|
+)
+(
+ Debug( ... );
+&
+ ... when != buf
+)
+(
+ ldap_pvt_thread_mutex_unlock(lock);
+|
+)
+(
+|
+ continue;
+|
+ break;
+|
+ goto id;
+|
+ \(
+ return E;
+ \&
+ ... when != buf
+ \)
+)
+}
+
+// the rest identifies and removes a (newly-)redundant LogTest check
+@if_guard@
+position p;
+statement s;
+@@
+
+(
+ if ( ... ) {@p
+ Debug( ... );
+ } else s
+|
+ if ( ... ) {@p
+ Debug( ... );
+ }
+)
+
+@else_guard@
+position p;
+statement s;
+@@
+
+if ( ... ) s
+else {@p
+ Debug( ... );
+}
+
+@loop_guard@
+position p;
+@@
+
+(
+ while ( ... ) {@p
+ Debug( ... );
+ }
+|
+ for ( ...;...;... ) {@p
+ Debug( ... );
+ }
+)
+
+@@
+position p != { if_guard.p , else_guard.p, loop_guard.p };
+@@
+-{@p
+ Debug( ... );
+-}
+
+@useless_if@
+expression L;
+@@
+
+-if ( LogTest( L ) ) {
+ Debug( L, ... );
+-}