Re: [Qemu-block] [PATCH v2] qemu-io: add pattern file for write command

[Stefano Garzarella]

On Wed, May 29, 2019 at 02:46:24PM +0300, Denis Plotnikov wrote:
> The patch allows to provide a pattern file for write
> command. There was no similar ability before.
> ---
>  qemu-io-cmds.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++----
>  1 file changed, 54 insertions(+), 4 deletions(-)
> 
> diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
> index 09750a23ce..148f2ff92a 100644
> --- a/qemu-io-cmds.c
> +++ b/qemu-io-cmds.c
> @@ -21,6 +21,7 @@
>  #include "qemu/option.h"
>  #include "qemu/timer.h"
>  #include "qemu/cutils.h"
> +#include "string.h"
>  
>  #define CMD_NOFILE_OK   0x01
>  
> @@ -343,6 +344,35 @@ static void *qemu_io_alloc(BlockBackend *blk, size_t 
> len, int pattern)
>      return buf;
>  }
>  
> +static void *qemu_io_alloc_from_file(BlockBackend *blk, size_t len,
> +                                     char *file_name)
> +{
> +    void *buf;
> +    FILE *f = fopen(file_name, "r");
> +
> +    if (!f) {
> +        printf("cannot open file '%s'\n", file_name);
> +        return NULL;
> +    }
> +
> +    if (qemuio_misalign) {
> +        len += MISALIGN_OFFSET;
> +    }
> +    buf = blk_blockalign(blk, len);
> +    memset(buf, 0, len);
> +
> +    if (!fread(buf, sizeof(char), len, f)) {
> +        printf("file '%s' is empty\n", file_name);
> +        qemu_vfree(buf);
> +        return NULL;
> +    }

Should we close the FILE *f at the end of this function or when fread()
returns with an error?

Thanks,
Stefano