LANG.ERRCODE.NOTEST : Missing Test of Error Code

The code calls a function that sets errno to non-zero on failure, but does not subsequently check whether errno is equal to zero.

The functions that are subject to this checking are specified using the ERRNO_SETTING_FUNCTIONS configuration parameter.

To specify that function f() sets errno and should be subject to checking for this class, add a new ERRNO_SETTING_FUNCTIONS rule to your configuration file.

ERRNO_SETTING_FUNCTIONS += f

To exclude a function from checking for this class, comment out the corresponding ERRNO_SETTING_FUNCTIONS rule.

ERRNO_SETTING_FUNCTIONS is also used by the Inappropriate Test of Error Code warning class.

プロパティ

クラス名

Missing Test of Error Code

日本語クラス名

Missing Test of Error Code

クラス分類

スタイル (style)

ニーモニック

LANG.ERRCODE.NOTEST

カテゴリー

MisraC2023	MisraC2023:22.9	The value of errno shall be tested against zero after calling an errno-setting-function
	MisraC2023:D.4.7	If a function returns error information, then that error information shall be tested
Misra2012	Misra2012:22.9	The value of errno shall be tested against zero after calling an errno-setting-function
	Misra2012:D.4.7	If a function returns error information, then that error information shall be tested
Misra2004	Misra2004:16.10	If a function returns error information, then that error information shall be tested
AUTOSARC++14	AUTOSARC++14:M0-3-2	If a function generates error information, then that error information shall be tested.
MisraC++2008	MisraC++2008:0-3-2	If a function generates error information, then that error information shall be tested.
TS17961	TS17961:5.24-inverrno	5.24. Incorrectly setting and using errno
CERT-C	CERT-C:ERR33-C	Detect and handle standard library errors
	CERT-C:POS54-C	Detect and handle POSIX library errors

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="Missing Test of Error Code"

例

#include <errno.h>
#include <stdio.h>

int compare_to_zero(FILE *fp){

  (void) ftell(fp);                /* 'Missing Test of Error Code' warning issued here
                                    * - errno is not checked between return from this call and the next call to ftell()
                                    */

  (void) ftell(fp);                                   /* ok: immediately followed by check errno!=0 */
  if (errno != 0){ return 1; }

  (void) ftell(fp);                                   /* ok: immediately followed by check errno==0 */
  if (errno == 0) {  }
  else {return 1;}

  (void) ftell(fp);                /* 'Missing Test of Error Code' warning issued here
                                    * - following check errno>0 is not a test for equality with zero
                                    */
  if (errno > 0){ return 1; }

  return 0;
}

int compare_to_nonzero(FILE *fp){
  (void) ftell(fp);                /* 'Missing Test of Error Code' warning issued here
                                    * - following check errno==15 is not a test for equality with zero
                                    */
  if (errno == 15){ return 1; }
  return 0;
}

int not_all_paths(FILE *fp, int i){
  (void) ftell(fp);                /* 'Missing Test of Error Code' warning issued here
                                    * - errno is not checked when i!=100
                                    */
  if (i == 100){
    if (errno!=0) {return 1;}
  }
  return 0;
}

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。