C and C++

LANG.STRUCT.RPNTC : Returned Pointer Not Treated as const

要旨

The value returned by one of the following functions is treated as if it is not a pointer to const-qualified type.

プロパティ

クラス名 Returned Pointer Not Treated as const
日本語クラス名 Returned Pointer Not Treated as const
クラス分類 セキュリティ (security)
ニーモニック LANG.STRUCT.RPNTC
カテゴリー
MisraC2023 MisraC2023:21.19 The pointers returned by the Standard Library functions localeconv, getenv, setlocale or, strerror shall only be used as if they have pointer to const-qualified type
Misra2012 Misra2012:21.19 The pointers returned by the Standard Library functions localeconv, getenv, setlocale or, strerror shall only be used as if they have pointer to const-qualified type
TS17961 TS17961:5.28-libmod 5.28. Modifying the string returned by getenv, localeconv, setlocale, and strerror
CERT-C CERT-C:DCL00-C Const-qualify immutable objects
  CERT-C:ENV30-C Do not modify the object referenced by the return value of certain functions
対応言語 C および C++ で利用可能です。
有効/無効設定 このワーニングクラスのチェックはデフォルトで無効になっています。チェックを有効にするにはプロジェクト設定ファイル （configuration file）に以下の WARNING_FILTER ルールを追加してください。 
WARNING_FILTER += allow class="Returned Pointer Not Treated as const"

例 

#include <stdlib.h>
#include <string.h>

/*  The value of an environment variable can change, so getenv(name)
 *  for fixed name may have different values at different program
 *  points.
 */
char * lang_struct_rpntc(char *name, char str[128]){
  char *c;       
  const char *cc;
  
  c = getenv(name);        /* 'Returned Pointer Not Treated as const' warning issued here.
                            * The code does not subsequently mutate *c, but future changes could
                            * introduce a mutation without causing compilation errors.
                            * Use a const-qualified variable to prevent this.
                            */
  if (!c){return NULL;}
  cc = getenv(name);                       /* ok: const-qualified pointer type */
  if (!cc){return NULL;}
  
  getenv(name)[0] = 'X';   /* 'Returned Pointer Not Treated as const' warning issued here
                            * ('Null Pointer Dereference' warning also issued: getenv() may return NULL)
                            */ 

  return strncpy(str, getenv(name), 127);  /* no 'Returned Pointer Not Treated as const' warning
                                            * - strcpy type signature is
                                            * char *strncpy (char *, const char *, size_t)
                                            */
                            /* ('Null Pointer Dereference' warning issued: getenv() may return NULL) */ 
}

関連のある設定ファイルパラメータ

設定ファイルの以下のパラメータがこのワーニングクラスのチェックに影響します。