[RFC weston] Add strtoint() helper

Thiago Macieira thiago at kde.org
Fri Jul 15 00:35:55 UTC 2016

On quinta-feira, 14 de julho de 2016 13:03:34 PDT Bryce Harrington wrote:
> +       ret = strtol(str, &end, 10);

Here you made a cast from long to int, which may be a loss of data.

	ret = strtol("4294967296", &end, 10);

Will produce no errno since it's in the valid range of long on LP64 systems, 
and yet ret = 0.

You should define ret to be a long and then later do:

	*value = (int)ret;
	if ((long)*value != ret) {
		errno = ERANGE;
		return false;

On systems where long and int are the same (ILP32, LLP64), the conditional is 
optimised out of existence by the compiler.

The casts are really optional, but since this in a header, some people may 
want to try and use it with annoying compiler options like -Wconversion.

Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
   Software Architect - Intel Open Source Technology Center

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