[PATCH] Fix unused return value warnings

[Simon Horman]

On Fri, Mar 12, 2010 at 05:27:24PM +0200, Ameya Palande wrote:
> From: Ameya Palande <ameya.palande at nokia.com>
> This patch fixes following warning:
> 
> kexec/firmware_memmap.c: In function ‘parse_numeric_sysfs’:
> kexec/firmware_memmap.c:70: error: ignoring return value of ‘fgets’, declared
> with attribute warn_unused_result
> kexec/firmware_memmap.c: In function ‘parse_string_sysfs’:
> kexec/firmware_memmap.c:103: error: ignoring return value of ‘fgets’, declared
> with attribute warn_unused_result
> 
> Signed-off-by: Ameya Palande <ameya.palande at nokia.com>
> ---
>  kexec/firmware_memmap.c |   32 +++++++++++++++++++-------------
>  1 files changed, 19 insertions(+), 13 deletions(-)
> 
> diff --git a/kexec/firmware_memmap.c b/kexec/firmware_memmap.c
> index 5a101fb..70e0f74 100644
> --- a/kexec/firmware_memmap.c
> +++ b/kexec/firmware_memmap.c
> @@ -67,11 +67,14 @@ static unsigned long long parse_numeric_sysfs(const char *filename)
>  		return ULLONG_MAX;
>  	}
>  
> -	fgets(linebuffer, BUFSIZ, fp);
> -	linebuffer[BUFSIZ-1] = 0;
> +	if(fgets(linebuffer, BUFSIZ, fp)) {
> +		linebuffer[BUFSIZ-1] = 0;
>  
> -	/* let strtoll() detect the base */
> -	retval = strtoll(linebuffer, NULL, 0);
> +		/* let strtoll() detect the base */
> +		retval = strtoll(linebuffer, NULL, 0);
> +	} else {
> +		retval = ULLONG_MAX;
> +	}
>  
>  	fclose(fp);

Could we change the style of this to something less-nested?
Also, there needs to be a space after if.

	unsigned long long retval = ULLONG_MAX;

	...

	if (!fgets(linebuffer, BUFSIZ, fp))
		goto err;

	linebuffer[BUFSIZ-1] = 0;

	/* let strtoll() detect the base */
	retval = strtoll(linebuffer, NULL, 0);
err:
	fclose(fp);

>  
> @@ -100,18 +103,21 @@ static char *parse_string_sysfs(const char *filename)
>  		return NULL;
>  	}
>  
> -	fgets(linebuffer, BUFSIZ, fp);
> -	linebuffer[BUFSIZ-1] = 0;
> -
> -	/* truncate trailing newline(s) */
> -	end = linebuffer + strlen(linebuffer) - 1;
> -	while (*end == '\n')
> -		*end-- = 0;
> +	if (fgets(linebuffer, BUFSIZ, fp)) {
> +		linebuffer[BUFSIZ-1] = 0;
>  
> -	fclose(fp);
> +		/* truncate trailing newline(s) */
> +		end = linebuffer + strlen(linebuffer) - 1;
>  
> -	return linebuffer;
> +		while (*end == '\n')
> +			*end-- = 0;
>  
> +		fclose(fp);
> +		return linebuffer;
> +	} else {
> +		fclose(fp);
> +		return NULL;
> +	}
>  }

Again, I would prefer something less-nested.