[CRIU] [PATCH v2 1/2] util: xatol() and xatoi() helpers introduced

[Andrei Vagin]

On Wed, Sep 13, 2017 at 04:48:50PM +0300, Stanislav Kinsburskiy wrote:
> These helpers are safe versions of atol() and atoi() respectively.
> And they check for overflow and NAN errors
> 
> Signed-off-by: Stanislav Kinsburskiy <skinsbursky at virtuozzo.com>
> ---
>  criu/include/util.h |    3 +++
>  criu/util.c         |   38 ++++++++++++++++++++++++++++++++++++++
>  2 files changed, 41 insertions(+)
> 
> diff --git a/criu/include/util.h b/criu/include/util.h
> index 1fc20db..20684cc 100644
> --- a/criu/include/util.h
> +++ b/criu/include/util.h
> @@ -280,6 +280,9 @@ void tcp_cork(int sk, bool on);
>  
>  const char *ns_to_string(unsigned int ns);
>  
> +int xatol(const char *string, long *number);
> +int xatoi(const char *string, int *number);
> +
>  char *xstrcat(char *str, const char *fmt, ...)
>  	__attribute__ ((__format__ (__printf__, 2, 3)));
>  char *xsprintf(const char *fmt, ...)
> diff --git a/criu/util.c b/criu/util.c
> index b5a161f..7d60617 100644
> --- a/criu/util.c
> +++ b/criu/util.c
> @@ -58,6 +58,44 @@
>  
>  #define VMA_OPT_LEN	128
>  
> +static int xatol_base(const char *string, long *number, int base)
> +{
> +	char *endptr;
> +	long nr;
> +
> +	errno = 0;
> +	nr = strtol(string, &endptr, base);
> +	if ((errno == ERANGE && (nr == LONG_MAX || nr == LONG_MIN))
> +			|| (errno != 0 && nr == 0)) {
> +		pr_perror("failed to convert string");

It is better to print this string in a error message

> +		return -EINVAL;
> +	}
> +
> +	if ((endptr == string) || (*endptr != '\0')) {
> +		pr_err("String is not a number: '%s'\n", string);
> +		return -EINVAL;
> +	}
> +	*number = nr;
> +	return 0;
> +}
> +
> +int xatol(const char *string, long *number)
> +{
> +	return xatol_base(string, number, 10);
> +}
> +
> +
> +int xatoi(const char *string, int *number)
> +{
> +	long tmp;
> +	int err;
> +
> +	err = xatol(string, &tmp);

Should we check that tmp is in [INT_MIN, INT_MAX]?
> +	if (!err)
> +		*number = (int)tmp;
> +	return err;
> +}
> +
>  /*
>   * This function reallocates passed str pointer.
>   * It means:
> 
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