1/* Copyright (c) 2013-2017 Jeffrey Pfau
  2 *
  3 * This Source Code Form is subject to the terms of the Mozilla Public
  4 * License, v. 2.0. If a copy of the MPL was not distributed with this
  5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
  6#include <mgba-util/vfs.h>
  7#include <mgba-util/circle-buffer.h>
  8
  9struct VFileFIFO {
 10	struct VFile d;
 11	struct CircleBuffer* backing;
 12};
 13
 14static bool _vffClose(struct VFile* vf);
 15static off_t _vffSeek(struct VFile* vf, off_t offset, int whence);
 16static ssize_t _vffRead(struct VFile* vf, void* buffer, size_t size);
 17static ssize_t _vffWrite(struct VFile* vf, const void* buffer, size_t size);
 18static void* _vffMap(struct VFile* vf, size_t size, int flags);
 19static void _vffUnmap(struct VFile* vf, void* memory, size_t size);
 20static void _vffTruncate(struct VFile* vf, size_t size);
 21static ssize_t _vffSize(struct VFile* vf);
 22static bool _vffSync(struct VFile* vf, const void* buffer, size_t size);
 23
 24struct VFile* VFileFIFO(struct CircleBuffer* backing) {
 25	if (!backing) {
 26		return NULL;
 27	}
 28
 29	struct VFileFIFO* vff = malloc(sizeof(*vff));
 30	if (!vff) {
 31		return NULL;
 32	}
 33
 34	vff->backing = backing;
 35	vff->d.close = _vffClose;
 36	vff->d.seek = _vffSeek;
 37	vff->d.read = _vffRead;
 38	vff->d.readline = VFileReadline;
 39	vff->d.write = _vffWrite;
 40	vff->d.map = _vffMap;
 41	vff->d.unmap = _vffUnmap;
 42	vff->d.truncate = _vffTruncate;
 43	vff->d.size = _vffSize;
 44	vff->d.sync = _vffSync;
 45
 46	return &vff->d;
 47}
 48
 49
 50static bool _vffClose(struct VFile* vf) {
 51	free(vf);
 52	return true;
 53}
 54
 55static off_t _vffSeek(struct VFile* vf, off_t offset, int whence) {
 56	UNUSED(vf);
 57	UNUSED(offset);
 58	UNUSED(whence);
 59	return 0;
 60}
 61
 62static ssize_t _vffRead(struct VFile* vf, void* buffer, size_t size) {
 63	struct VFileFIFO* vff = (struct VFileFIFO*) vf;
 64	return CircleBufferRead(vff->backing, buffer, size);
 65}
 66
 67static ssize_t _vffWrite(struct VFile* vf, const void* buffer, size_t size) {
 68	struct VFileFIFO* vff = (struct VFileFIFO*) vf;
 69	return CircleBufferWrite(vff->backing, buffer, size);
 70}
 71
 72static void* _vffMap(struct VFile* vf, size_t size, int flags) {
 73	UNUSED(vf);
 74	UNUSED(size);
 75	UNUSED(flags);
 76	return NULL;
 77}
 78
 79static void _vffUnmap(struct VFile* vf, void* memory, size_t size) {
 80	UNUSED(vf);
 81	UNUSED(memory);
 82	UNUSED(size);
 83}
 84
 85static void _vffTruncate(struct VFile* vf, size_t size) {
 86	struct VFileFIFO* vff = (struct VFileFIFO*) vf;
 87	if (!size) {
 88		CircleBufferClear(vff->backing);
 89	}
 90}
 91
 92static ssize_t _vffSize(struct VFile* vf) {
 93	struct VFileFIFO* vff = (struct VFileFIFO*) vf;
 94	return CircleBufferSize(vff->backing);
 95}
 96
 97static bool _vffSync(struct VFile* vf, const void* buffer, size_t size) {
 98	UNUSED(vf);
 99	UNUSED(buffer);
100	UNUSED(size);
101	return true;
102}