1/// Many iterators have the property that the first argument is always bound 2/// to a real list element, never NULL. 3//# False positives arise for some iterators that do not have this property, 4//# or in cases when the loop cursor is reassigned. The latter should only 5//# happen when the matched code is on the way to a loop exit (break, goto, 6//# or return). 7/// 8// Confidence: Moderate 9// Copyright: (C) 2010-2012 Nicolas Palix. GPLv2. 10// Copyright: (C) 2010-2012 Julia Lawall, INRIA/LIP6. GPLv2. 11// Copyright: (C) 2010-2012 Gilles Muller, INRIA/LiP6. GPLv2. 12// URL: http://coccinelle.lip6.fr/ 13// Comments: 14// Options: --no-includes --include-headers 15 16virtual patch 17virtual context 18virtual org 19virtual report 20 21@depends on patch@ 22iterator I; 23expression x,E,E1,E2; 24statement S,S1,S2; 25@@ 26 27I(x,...) { <... 28( 29- if (x == NULL && ...) S 30| 31- if (x != NULL || ...) 32 S 33| 34- (x == NULL) || 35 E 36| 37- (x != NULL) && 38 E 39| 40- (x == NULL && ...) ? E1 : 41 E2 42| 43- (x != NULL || ...) ? 44 E1 45- : E2 46| 47- if (x == NULL && ...) S1 else 48 S2 49| 50- if (x != NULL || ...) 51 S1 52- else S2 53| 54+ BAD( 55 x == NULL 56+ ) 57| 58+ BAD( 59 x != NULL 60+ ) 61) 62 ...> } 63 64@r depends on !patch exists@ 65iterator I; 66expression x,E; 67position p1,p2; 68@@ 69 70*I@p1(x,...) 71{ ... when != x = E 72( 73* x@p2 == NULL 74| 75* x@p2 != NULL 76) 77 ... when any 78} 79 80@script:python depends on org@ 81p1 << r.p1; 82p2 << r.p2; 83@@ 84 85cocci.print_main("iterator-bound variable",p1) 86cocci.print_secs("useless NULL test",p2) 87 88@script:python depends on report@ 89p1 << r.p1; 90p2 << r.p2; 91@@ 92 93msg = "ERROR: iterator variable bound on line %s cannot be NULL" % (p1[0].line) 94coccilib.report.print_report(p2[0], msg) 95