Re: [PATCH 2/9] libxl: turn two malloc's to libxl__malloc

[Ian Campbell <ian.campbell@citrix.com>]

On Fri, 2015-07-10 at 19:00 +0100, Wei Liu wrote:
> One is to combine malloc + libxl__alloc_failed. The other is to avoid
> dereferencing NULL pointer in case of malloc failure.

The non-use of a gc for the latter in particular looks a bit suspicious
to me, but nonetheless this is an improvement:

> Signed-off-by: Wei Liu <wei.liu2@citrix.com>

Acked-by: Ian Campbell <ian.campbell@citrix.com>

> ---
>  tools/libxl/libxl_aoutils.c | 3 +--
>  tools/libxl/libxl_dm.c      | 2 +-
>  2 files changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/tools/libxl/libxl_aoutils.c b/tools/libxl/libxl_aoutils.c
> index 0931eee..0300396 100644
> --- a/tools/libxl/libxl_aoutils.c
> +++ b/tools/libxl/libxl_aoutils.c
> @@ -245,8 +245,7 @@ static void datacopier_readable(libxl__egc *egc, libxl__ev_fd *ev,
>  
>              buf = LIBXL_TAILQ_LAST(&dc->bufs, libxl__datacopier_bufs);
>              if (!buf || buf->used >= sizeof(buf->buf)) {
> -                buf = malloc(sizeof(*buf));
> -                if (!buf) libxl__alloc_failed(CTX, __func__, 1, sizeof(*buf));
> +                buf = libxl__malloc(NOGC, sizeof(*buf));
>                  buf->used = 0;
>                  LIBXL_TAILQ_INSERT_TAIL(&dc->bufs, buf, entry);
>              }
> diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c
> index ad434f0..0cc73be 100644
> --- a/tools/libxl/libxl_dm.c
> +++ b/tools/libxl/libxl_dm.c
> @@ -1010,7 +1010,7 @@ static int libxl__write_stub_dmargs(libxl__gc *gc,
>          i++;
>      }
>      dmargs_size++;
> -    dmargs = (char *) malloc(dmargs_size);
> +    dmargs = (char *) libxl__malloc(NOGC, dmargs_size);
>      i = 1;
>      dmargs[0] = '\0';
>      while (args[i] != NULL) {