[Qemu-devel] Re: [PATCH] Win32: Fix build (no strnlen)

[Consul <void@aleksoft.net>]

Stefan Weil wrote:
> strnlen is a GNU extension which is missing in mingw32
> and perhaps other build environments.
> 
> So we should avoid it and replace it by standard functions.
> 
> Signed-off-by: Stefan Weil <weil@mail.berlios.de>
> ---
>  block.c |    7 ++++++-
>  1 files changed, 6 insertions(+), 1 deletions(-)
> 
> diff --git a/block.c b/block.c
> index c66c031..79b3313 100644
> --- a/block.c
> +++ b/block.c
> @@ -225,9 +225,14 @@ static BlockDriver *find_protocol(const char *filename)
>  {
>      BlockDriver *drv1;
>      char protocol[128];
> -    int len = strnlen(filename, 127)+1;
> +    int len;
>      const char *p;
>  
> +    len = strlen(filename) + 1;
> +    if (len > sizeof(protocol)) {
> +      len = sizeof(protocol);
> +    }
> +
>  #ifdef _WIN32
>      if (is_windows_drive(filename) ||
>          is_windows_drive_prefix(filename))

Or something like this?
#ifdef __MINGW32__
size_t strnlen (const char *string, size_t maxlen)
{
   const char *end = memchr (string, '\0', maxlen);
   return end ? (size_t) (end - string) : maxlen;
};
#endif