demos/sgrep/null.sgrep

   1 @@
   2 expression x;
   3 type T1, T2, T3;
   4 expression e1, e2;
   5 expression f;
   6 identifier fld;
   7 @@
   8   x = (T1) kmalloc(...)
   9   ... when != x = e1
  10   if(x == NULL) {
  11     ... when != x = e2
  12 (
  13     *x
  14 |
  15     *((T2)x)
  16 |
  17     x->fld
  18 |
  19     (x)->fld
  20 |
  21     f(...,x,...)
  22 |
  23     f(...,(T3)x,...)
  24 )
  25     ...
  26   }
  27
  28 @@
  29 expression x;
  30 type T1, T2, T3;
  31 expression e1, e2;
  32 expression f;
  33 identifier fld;
  34 statement S;
  35 @@
  36   x = (T1) kmalloc(...)
  37   ... when != x = e1
  38   if(x != NULL) S else {
  39     ... when != x = e2
  40 (
  41     *x
  42 |
  43     *((T2)x)
  44 |
  45     x->fld
  46 |
  47     (x)->fld
  48 |
  49     f(...,x,...)
  50 |
  51     f(...,(T3)x,...)
  52 )
  53     ...
  54   }
  55
  56 // for some "good" reason, isomorphisms don't apply to whencode
  57 @@
  58 expression x;
  59 type T1, T2, T3;
  60 expression e;
  61 expression f;
  62 identifier fld;
  63 statement S;
  64 @@
  65   x = (T1) kmalloc(...);
  66   ... when != \( if(\(x == NULL\|NULL == x\|!x\)) { ... \(return;\|return e;\)   } \| if(\(x == NULL\|NULL == x\|!x\)) \(return;\|return e;\) \| if(\(x != NULL\|NULL != x\|x\)) S else { ... \(return;\|return e;\) } \| if(\(x != NULL\|NULL != x\|x\)) S else \(return;\|return e;\) \| x = e; \)
  67 (
  68   *x
  69 |
  70   *((T2)x)
  71 |
  72   x->fld
  73 |
  74   (x)->fld
  75 |
  76   f(...,x,...)
  77 |
  78   f(...,(T3)x,...)
  79 )
  80
  81 @@
  82 expression x;
  83 type T1;
  84 expression e1, e2;
  85 @@
  86   x = (T1) kmalloc(...)
  87   ... when != x = e1
  88   if(x == NULL) {
  89     ... when != x = e2
  90     return x;
  91   }
  92
  93 // for some "good" reason, isomorphisms don't apply to whencode
  94 @@
  95 expression x;
  96 type T1;
  97 expression e;
  98 @@
  99   x = (T1) kmalloc(...);
 100   ... when != \( if(\(x == NULL\|NULL == x\|!x\)) { ... \(return;\|return e;\) } \| if(\(x == NULL\|NULL == x\|!x\)) \(return;\|return e;\) \| x = e; \)
 101   return x;