[sheepdog] [PATCH v2 2/3] move parse_option_size to lib/option.c

[Liu Yuan]

On Mon, Aug 26, 2013 at 02:06:54PM +0900, MORITA Kazutaka wrote:
> At Mon, 26 Aug 2013 13:01:33 +0800,
> Liu Yuan wrote:
> > 
> > On Mon, Aug 26, 2013 at 11:23:14AM +0900, Hitoshi Mitake wrote:
> > > At Fri, 23 Aug 2013 20:40:53 +0800,
> > > Liu Yuan wrote:
> > > > 
> > > > Signed-off-by: Liu Yuan <namei.unix at gmail.com>
> > > > ---
> > > >  dog/vdi.c        |   42 ++++++------------------------------------
> > > >  include/option.h |    1 +
> > > >  lib/option.c     |   33 +++++++++++++++++++++++++++++++++
> > > >  3 files changed, 40 insertions(+), 36 deletions(-)
> > > > 
> > > > diff --git a/dog/vdi.c b/dog/vdi.c
> > > > index 3eb03dd..65c9bac 100644
> > > > --- a/dog/vdi.c
> > > > +++ b/dog/vdi.c
> > > > @@ -55,36 +55,6 @@ struct get_vdi_info {
> > > >  	uint8_t nr_copies;
> > > >  };
> > > >  
> > > > -static int parse_option_size(const char *value, uint64_t *ret)
> > > > -{
> > > > -	char *postfix;
> > > > -	double sizef;
> > > > -
> > > > -	sizef = strtod(value, &postfix);
> > > > -	switch (*postfix) {
> > > > -	case 'T':
> > > > -		sizef *= 1024;
> > > > -	case 'G':
> > > > -		sizef *= 1024;
> > > > -	case 'M':
> > > > -		sizef *= 1024;
> > > > -	case 'K':
> > > > -	case 'k':
> > > > -		sizef *= 1024;
> > > > -	case 'b':
> > > > -	case '\0':
> > > > -		*ret = (uint64_t) sizef;
> > > > -		break;
> > > > -	default:
> > > > -		sd_err("Invalid size '%s'", value);
> > > > -		sd_err("You may use k, M, G or T suffixes for "
> > > > -		       "kilobytes, megabytes, gigabytes and terabytes.");
> > > > -		return -1;
> > > > -	}
> > > > -
> > > > -	return 0;
> > > > -}
> > > > -
> > > >  static void vdi_show_progress(uint64_t done, uint64_t total)
> > > >  {
> > > >  	return show_progress(done, total, false);
> > > > @@ -502,7 +472,7 @@ static int vdi_create(int argc, char **argv)
> > > >  		sd_err("Please specify the VDI size");
> > > >  		return EXIT_USAGE;
> > > >  	}
> > > > -	ret = parse_option_size(argv[optind], &size);
> > > > +	ret = option_parse_size(argv[optind], &size);
> > > >  	if (ret < 0)
> > > >  		return EXIT_USAGE;
> > > >  	if (size > SD_MAX_VDI_SIZE) {
> > > > @@ -699,7 +669,7 @@ static int vdi_resize(int argc, char **argv)
> > > >  		sd_err("Please specify the new size for the VDI");
> > > >  		return EXIT_USAGE;
> > > >  	}
> > > > -	ret = parse_option_size(argv[optind], &new_size);
> > > > +	ret = option_parse_size(argv[optind], &new_size);
> > > >  	if (ret < 0)
> > > >  		return EXIT_USAGE;
> > > >  	if (new_size > SD_MAX_VDI_SIZE) {
> > > > @@ -1160,11 +1130,11 @@ static int vdi_read(int argc, char **argv)
> > > >  	char *buf = NULL;
> > > >  
> > > >  	if (argv[optind]) {
> > > > -		ret = parse_option_size(argv[optind++], &offset);
> > > > +		ret = option_parse_size(argv[optind++], &offset);
> > > >  		if (ret < 0)
> > > >  			return EXIT_USAGE;
> > > >  		if (argv[optind]) {
> > > > -			ret = parse_option_size(argv[optind++], &total);
> > > > +			ret = option_parse_size(argv[optind++], &total);
> > > >  			if (ret < 0)
> > > >  				return EXIT_USAGE;
> > > >  		}
> > > > @@ -1234,11 +1204,11 @@ static int vdi_write(int argc, char **argv)
> > > >  	bool create;
> > > >  
> > > >  	if (argv[optind]) {
> > > > -		ret = parse_option_size(argv[optind++], &offset);
> > > > +		ret = option_parse_size(argv[optind++], &offset);
> > > >  		if (ret < 0)
> > > >  			return EXIT_USAGE;
> > > >  		if (argv[optind]) {
> > > > -			ret = parse_option_size(argv[optind++], &total);
> > > > +			ret = option_parse_size(argv[optind++], &total);
> > > >  			if (ret < 0)
> > > >  				return EXIT_USAGE;
> > > >  		}
> > > > diff --git a/include/option.h b/include/option.h
> > > > index 3a1eb20..ba62496 100644
> > > > --- a/include/option.h
> > > > +++ b/include/option.h
> > > > @@ -31,6 +31,7 @@ char *build_short_options(const struct sd_option *opts);
> > > >  struct option *build_long_options(const struct sd_option *opts);
> > > >  const char *option_get_help(const struct sd_option *, int);
> > > >  int option_parse(char *arg, const char *delim, struct option_parser *parsers);
> > > > +int option_parse_size(const char *value, uint64_t *ret);
> > > >  
> > > >  #define sd_for_each_option(opt, opts)		\
> > > >  	for (opt = (opts); opt->name; opt++)
> > > > diff --git a/lib/option.c b/lib/option.c
> > > > index 39a4c52..8f52371 100644
> > > > --- a/lib/option.c
> > > > +++ b/lib/option.c
> > > > @@ -61,6 +61,39 @@ const char *option_get_help(const struct sd_option *sd_opts, int ch)
> > > >  	return NULL;
> > > >  }
> > > >  
> > > > +int option_parse_size(const char *value, uint64_t *ret)
> > > > +{
> > > > +	char *postfix;
> > > > +	double sizef;
> > > > +
> > > > +	sizef = strtod(value, &postfix);
> > > > +	switch (*postfix) {
> > > > +	case 'T':
> > > > +	case 't':
> > > > +		sizef *= 1024;
> > > > +	case 'G':
> > > > +	case 'g':
> > > > +		sizef *= 1024;
> > > > +	case 'M':
> > > > +	case 'm':
> > > > +		sizef *= 1024;
> > > > +	case 'K':
> > > > +	case 'k':
> > > > +		sizef *= 1024;
> > > > +	case 'b':
> > > > +	case '\0':
> > > > +		*ret = (uint64_t) sizef;
> > > > +		break;
> > > > +	default:
> > > > +		sd_err("Invalid size '%s'", value);
> > > > +		sd_err("You may use k, M, G or T suffixes for "
> > > > +		       "kilobytes, megabytes, gigabytes and terabytes.");
> > > > +		return -1;
> > > > +	}
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > 
> > > Current option_parse_size() interprets strings like "128GMB" as
> > > correct things. This behavior wouldn't be able to catch configuration
> > > mistakes.
> > > 
> > > How about this?
> > > 
> > > int option_parse_size(const char *value, uint64_t *ret)
> > > {
> > > 	char *postfix;
> > > 	double sizef;
> > > 
> > > 	sizef = strtod(value, &postfix);
> > > 	if (!(postfix[0] == '\0' || postfix[1] == 'b' ||
> > > 	      postfix[1] == 'B' || postfix[1] == '\0')) {
> > 
> > simply check postfix[1] != '\0' is good enough to me
> 
> It can cause a buffer overflow when strlen(postfix) == 0.  In
> addition, there is no guarantee that postfix[1] is '\0' when
> postfix[0] == '\0'.
> 

I tried 

if (postfix[0] != '\0' && postfix[1] != '\0')

And it seems to work on all cases.

Thanks
Yuan