svn commit: r309839 - head/sbin/camcontrol

[Warner Losh]

Why not just unconditionally free them? You don't need to NULL them
out. That would save a IMHO bogus macro.

On Sat, Dec 10, 2016 at 4:26 PM, Ngie Cooper <ngie at freebsd.org> wrote:
> Author: ngie
> Date: Sat Dec 10 23:26:34 2016
> New Revision: 309839
> URL: https://svnweb.freebsd.org/changeset/base/309839
>
> Log:
>   free/NULL out variables prior to calling strdup to avoid leaking memory
>   if arguments are specified more than once with "camcontrol timestamp".
>
>   CID:          1366829, 1366831
>   MFC after:    1 week
>
> Modified:
>   head/sbin/camcontrol/timestamp.c
>
> Modified: head/sbin/camcontrol/timestamp.c
> ==============================================================================
> --- head/sbin/camcontrol/timestamp.c    Sat Dec 10 22:31:49 2016        (r309838)
> +++ head/sbin/camcontrol/timestamp.c    Sat Dec 10 23:26:34 2016        (r309839)
> @@ -336,6 +336,11 @@ timestamp(struct cam_device *device, int
>         int single_arg = 0;
>         int do_utc = 0;
>
> +#define        FREE(x) do {    \
> +       free(x);        \
> +       x = NULL;       \
> +} while(0)
> +
>         while ((c = getopt(argc, argv, combinedopt)) != -1) {
>                 switch (c) {
>                 case 'r': {
> @@ -358,6 +363,7 @@ timestamp(struct cam_device *device, int
>                 }
>                 case 'f': {
>                         single_arg++;
> +                       FREE(format_string);
>                         format_string = strdup(optarg);
>                         if (format_string == NULL) {
>                                 warn("Error allocating memory for format "
> @@ -369,6 +375,7 @@ timestamp(struct cam_device *device, int
>                 }
>                 case 'm': {
>                         single_arg++;
> +                       FREE(format_string);
>                         format_string = strdup(MIL);
>                         if (format_string == NULL) {
>                                 warn("Error allocating memory");
> @@ -382,6 +389,7 @@ timestamp(struct cam_device *device, int
>                         break;
>                 }
>                 case 'T':
> +                       FREE(timestamp_string);
>                         timestamp_string = strdup(optarg);
>                         if (timestamp_string == NULL) {
>                                 warn("Error allocating memory for format "
> @@ -395,6 +403,8 @@ timestamp(struct cam_device *device, int
>                 }
>         }
>
> +#undef FREE
> +
>         if (action == -1) {
>                 warnx("Must specify an action, either -r or -s");
>                 error = 1;
>