util: pull Buffer code out of VNC module (88c5f205) · Commits · SUMMER2020 / students / proj-2021291

MAINTAINERS

+6 −0

Original line number	Diff line number	Diff line
		@@ -1200,6 +1200,12 @@ F: util/coroutine
		F: include/qemu/coroutine*
		F: tests/test-coroutine.c

		Buffers
		M: Daniel P. Berrange <berrange@redhat.com>
		S: Odd fixes
		F: util/buffer.c
		F: include/qemu/buffer.h

		Usermode Emulation
		------------------
		Overall

include/qemu/buffer.h

0 → 100644

+118 −0

Original line number	Diff line number	Diff line
		/*
		* QEMU generic buffers
		*
		* Copyright (c) 2015 Red Hat, Inc.
		*
		* This library is free software; you can redistribute it and/or
		* modify it under the terms of the GNU Lesser General Public
		* License as published by the Free Software Foundation; either
		* version 2 of the License, or (at your option) any later version.
		*
		* This library is distributed in the hope that it will be useful,
		* but WITHOUT ANY WARRANTY; without even the implied warranty of
		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
		* Lesser General Public License for more details.
		*
		* You should have received a copy of the GNU Lesser General Public
		* License along with this library; if not, see <http://www.gnu.org/licenses/>.
		*
		*/

		#ifndef QEMU_BUFFER_H__
		#define QEMU_BUFFER_H__

		#include "qemu-common.h"

		typedef struct Buffer Buffer;

		/**
		* Buffer:
		*
		* The Buffer object provides a simple dynamically resizing
		* array, with separate tracking of capacity and usage. This
		* is typically useful when buffering I/O or processing data.
		*/

		struct Buffer {
		size_t capacity;
		size_t offset;
		uint8_t *buffer;
		};

		/**
		* buffer_reserve:
		* @buffer: the buffer object
		* @len: the minimum required free space
		*
		* Ensure that the buffer has space allocated for at least
		* @len bytes. If the current buffer is too small, it will
		* be reallocated, possibly to a larger size than requested.
		*/
		void buffer_reserve(Buffer *buffer, size_t len);

		/**
		* buffer_reset:
		* @buffer: the buffer object
		*
		* Reset the length of the stored data to zero, but do
		* not free / reallocate the memory buffer
		*/
		void buffer_reset(Buffer *buffer);

		/**
		* buffer_free:
		* @buffer: the buffer object
		*
		* Reset the length of the stored data to zero and also
		* free the internal memory buffer
		*/
		void buffer_free(Buffer *buffer);

		/**
		* buffer_append:
		* @buffer: the buffer object
		* @data: the data block to append
		* @len: the length of @data in bytes
		*
		* Append the contents of @data to the end of the buffer.
		* The caller must ensure that the buffer has sufficient
		* free space for @len bytes, typically by calling the
		* buffer_reserve() method prior to appending.
		*/
		void buffer_append(Buffer buffer, const void data, size_t len);

		/**
		* buffer_advance:
		* @buffer: the buffer object
		* @len: the number of bytes to skip
		*
		* Remove @len bytes of data from the head of the buffer.
		* The internal buffer will not be reallocated, so will
		* have at least @len bytes of free space after this
		* call completes
		*/
		void buffer_advance(Buffer *buffer, size_t len);

		/**
		* buffer_end:
		* @buffer: the buffer object
		*
		* Get a pointer to the tail end of the internal buffer
		* The returned pointer is only valid until the next
		* call to buffer_reserve().
		*
		* Returns: the tail of the buffer
		*/
		uint8_t buffer_end(Buffer buffer);

		/**
		* buffer_empty:
		* @buffer: the buffer object
		*
		* Determine if the buffer contains any current data
		*
		* Returns: true if the buffer holds data, false otherwise
		*/
		gboolean buffer_empty(Buffer *buffer);

		#endif /* QEMU_BUFFER_H__ */

ui/vnc.c

+0 −43

Original line number	Diff line number	Diff line
		@@ -647,49 +647,6 @@ void vnc_framebuffer_update(VncState *vs, int x, int y, int w, int h,
		vnc_write_s32(vs, encoding);
		}

		void buffer_reserve(Buffer *buffer, size_t len)
		{
		if ((buffer->capacity - buffer->offset) < len) {
		buffer->capacity += (len + 1024);
		buffer->buffer = g_realloc(buffer->buffer, buffer->capacity);
		}
		}

		static int buffer_empty(Buffer *buffer)
		{
		return buffer->offset == 0;
		}

		uint8_t buffer_end(Buffer buffer)
		{
		return buffer->buffer + buffer->offset;
		}

		void buffer_reset(Buffer *buffer)
		{
		buffer->offset = 0;
		}

		void buffer_free(Buffer *buffer)
		{
		g_free(buffer->buffer);
		buffer->offset = 0;
		buffer->capacity = 0;
		buffer->buffer = NULL;
		}

		void buffer_append(Buffer buffer, const void data, size_t len)
		{
		memcpy(buffer->buffer + buffer->offset, data, len);
		buffer->offset += len;
		}

		void buffer_advance(Buffer *buf, size_t len)
		{
		memmove(buf->buffer, buf->buffer + len,
		(buf->offset - len));
		buf->offset -= len;
		}

		static void vnc_desktop_resize(VncState *vs)
		{

ui/vnc.h

+1 −15

Original line number	Diff line number	Diff line
		@@ -34,6 +34,7 @@
		#include "audio/audio.h"
		#include "qemu/bitmap.h"
		#include "crypto/tlssession.h"
		#include "qemu/buffer.h"
		#include <zlib.h>
		#include <stdbool.h>

		@@ -56,13 +57,6 @@
		*
		*****************************************************************************/

		typedef struct Buffer
		{
		size_t capacity;
		size_t offset;
		uint8_t *buffer;
		} Buffer;

		typedef struct VncState VncState;
		typedef struct VncJob VncJob;
		typedef struct VncRect VncRect;
		@@ -535,14 +529,6 @@ ssize_t vnc_client_io_error(VncState *vs, ssize_t ret, int last_errno);
		void start_client_init(VncState *vs);
		void start_auth_vnc(VncState *vs);

		/* Buffer management */
		void buffer_reserve(Buffer *buffer, size_t len);
		void buffer_reset(Buffer *buffer);
		void buffer_free(Buffer *buffer);
		void buffer_append(Buffer buffer, const void data, size_t len);
		void buffer_advance(Buffer *buf, size_t len);
		uint8_t buffer_end(Buffer buffer);


		/* Misc helpers */

util/Makefile.objs

+1 −0

Original line number	Diff line number	Diff line
		@@ -21,3 +21,4 @@ util-obj-y += rcu.o
		util-obj-y += qemu-coroutine.o qemu-coroutine-lock.o qemu-coroutine-io.o
		util-obj-y += qemu-coroutine-sleep.o
		util-obj-y += coroutine-$(CONFIG_COROUTINE_BACKEND).o
		util-obj-y += buffer.o