Coccinelle: Script to detect incorrect argument to sizeof

/// Use ARRAY_SIZE instead of dividing sizeof array with sizeof an element

///

//# This makes an effort to find cases where the argument to sizeof is wrong

//# in memory allocation functions by checking the type of the allocated memory

//# when it is a double pointer and ensuring the sizeof argument takes a pointer

//# to the the memory being allocated. There are false positives in cases the

//# sizeof argument is not used in constructing the return value. The result

//# may need some reformatting.

//

// Confidence: Moderate

// Copyright: (C) 2014 Himangi Saraogi.  GPLv2.

// Comments:

// Options:

virtual patch

virtual context

virtual org

virtual report

//----------------------------------------------------------

//  For context mode

//----------------------------------------------------------

@depends on context disable sizeof_type_expr@

type T;

T **x;

@@

  x =

  <+...sizeof(

* T

  )...+>

//----------------------------------------------------------

//  For patch mode

//----------------------------------------------------------

@depends on patch disable sizeof_type_expr@

type T;

T **x;

@@

  x =

  <+...sizeof(

- T

+ *x

  )...+>

//----------------------------------------------------------

//  For org and report mode

//----------------------------------------------------------

@r disable sizeof_type_expr@

type T;

T **x;

position p;

@@

  x =

  <+...sizeof(

  T@p

  )...+>

@script:python depends on org@

p << r.p;

@@

coccilib.org.print_todo(p[0], "WARNING sizeof argument should be pointer type, not structure type")

@script:python depends on report@

p << r.p;

@@

msg="WARNING: Use correct pointer type argument for sizeof"

coccilib.report.print_report(p[0], msg)