Re: [PATCH v12 7/9] trace-cmd: Implemented new API tracecmd_add_option_v()

[Steven Rostedt <rostedt@goodmis.org>]

On Wed, 28 Aug 2019 11:57:44 +0300
"Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com> wrote:

> +/**
> + * tracecmd_add_option - add options to the file
> + * @handle: the output file handle name
> + * @id: the id of the option
> + * @size: the size of the option data
> + * @data: the data to write to the file.
> + *
> + * Returns handle to update option if needed.
> + *  Just the content can be updated, with smaller or equal to
> + *  content than the specified size.
> + */
> +struct tracecmd_option *
> +tracecmd_add_option(struct tracecmd_output *handle,
> +		    unsigned short id, int size, const void *data)
> +{
> +	struct iovec vect;
> +
> +	vect.iov_base = (void *) data;

Remove the space between (void *) and data.

> +	vect.iov_len = size;
> +	return tracecmd_add_option_v(handle, id, &vect, 1);
> +}
> +
>  int tracecmd_write_cpus(struct tracecmd_output *handle, int cpus)
>  {
>  	cpus = convert_endian_4(handle, cpus);
> @@ -979,6 +1013,56 @@ int tracecmd_write_options(struct tracecmd_output *handle)
>  	return 0;
>  }
>  
> +int tracecmd_append_options(struct tracecmd_output *handle)

Hmm, this was added with no users, and was not mentioned in the change
log. Probably belongs in another patch.

-- Steve

> +{
> +	struct tracecmd_option *options;
> +	unsigned short option;
> +	unsigned short endian2;
> +	unsigned int endian4;
> +	off_t offset;
> +	int r;
> +
> +	/* If already written, ignore */
> +	if (handle->options_written)
> +		return 0;
> +
> +	if (lseek64(handle->fd, 0, SEEK_END) == (off_t)-1)
> +		return -1;
> +	offset = lseek64(handle->fd, -2, SEEK_CUR);
> +	if (offset == (off_t)-1)
> +		return -1;
> +
> +	r = pread(handle->fd, &option, 2, offset);
> +	if (r != 2 || option != TRACECMD_OPTION_DONE)
> +		return -1;
> +
> +	list_for_each_entry(options, &handle->options, list) {
> +		endian2 = convert_endian_2(handle, options->id);
> +		if (do_write_check(handle, &endian2, 2))
> +			return -1;
> +
> +		endian4 = convert_endian_4(handle, options->size);
> +		if (do_write_check(handle, &endian4, 4))
> +			return -1;
> +
> +		/* Save the data location in case it needs to be updated */
> +		options->offset = lseek64(handle->fd, 0, SEEK_CUR);
> +
> +		if (do_write_check(handle, options->data,
> +				   options->size))
> +			return -1;
> +	}
> +
> +	option = TRACECMD_OPTION_DONE;
> +
> +	if (do_write_check(handle, &option, 2))
> +		return -1;
> +
> +	handle->options_written = 1;
> +
> +	return 0;
> +}
> +
>  int tracecmd_update_option(struct tracecmd_output *handle,
>  			   struct tracecmd_option *option, int size,
>  			   const void *data)