Re: [PATCH v2 1/4] sha1sum: use AF_ALG when available

[Dmitry V. Levin]

On Wed, Apr 25, 2018 at 01:26:08PM +0200, Matteo Croce wrote:
[...]
> +#include <config.h>
> +
> +#include <sys/socket.h>
> +
> +#ifdef AF_ALG
> +
> +#include <unistd.h>
> +#include <string.h>
> +#include <linux/if_alg.h>
> +#include <sys/stat.h>
> +#include <sys/sendfile.h>
> +
> +#include "af_alg.h"
> +
> +/* from linux/include/linux/fs.h: (INT_MAX & PAGE_MASK) */
> +#define MAX_RW_COUNT 0x7FFFF000
> +#define BLOCKSIZE 32768
> +
> +int
> +afalg_stream (FILE * stream, void *resblock, const char *alg, ssize_t 
> hashlen)
> +{
> +  struct sockaddr_alg salg = {

As struct sockaddr_alg is not provided by glibc,
you'd have to check for HAVE_LINUX_IF_ALG_H after all.

[...]
> +  /* if file is a regular file, attempt sendfile() to pipe the data */
> +  if (!fstat (fileno (stream), &st) && S_ISREG (st.st_mode) &&
> +      st.st_size <= MAX_RW_COUNT)
> +    {
> +      if (sendfile (ofd, fileno (stream), NULL, st.st_size) != st.st_size)

Given that sendfile has offset argument, wouldn't it be better
to use a sendfile loop for handling large regular files?


-- 
ldv

signature.asc
Description: PGP signature