/* Copyright (c) 2002-2018 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "istream-private.h"

static ssize_t i_stream_data_read(struct istream_private *stream)
{
	stream->istream.eof = TRUE;
	return -1;
}

static void i_stream_data_seek(struct istream_private *stream, uoff_t v_offset,
			       bool mark ATTR_UNUSED)
{
	stream->skip = v_offset;
	stream->istream.v_offset = v_offset;
}

struct istream *i_stream_create_from_data(const void *data, size_t size)
{
	struct istream_private *stream;

	stream = i_new(struct istream_private, 1);
	stream->buffer = data;
	stream->pos = size;
	stream->max_buffer_size = SIZE_MAX;

	stream->read = i_stream_data_read;
	stream->seek = i_stream_data_seek;

	stream->istream.readable_fd = FALSE;
	stream->istream.blocking = TRUE;
	stream->istream.seekable = TRUE;
	i_stream_create(stream, NULL, -1, ISTREAM_CREATE_FLAG_NOOP_SNAPSHOT);
	stream->statbuf.st_size = size;
	i_stream_set_name(&stream->istream, "(buffer)");
	return &stream->istream;
}

static void i_stream_copied_data_free(void *data)
{
	i_free(data);
}
struct istream *
i_stream_create_copy_from_data(const void *data, size_t size)
{
	struct istream *stream;
	void *buffer;

	if (size == 0) {
		buffer = "";
	} else {
		buffer = i_malloc(size);
		memcpy(buffer, data, size);
	}
	stream = i_stream_create_from_data(buffer, size);
	if (size > 0) {
		i_stream_add_destroy_callback
			(stream, i_stream_copied_data_free, buffer);
	}
	return stream;
}