RetroArch/movie.c

257 lines
6.9 KiB
C

/* RetroArch - A frontend for libretro.
* Copyright (C) 2010-2014 - Hans-Kristian Arntzen
* Copyright (C) 2011-2015 - Daniel De Matteis
*
* RetroArch is free software: you can redistribute it and/or modify it under the terms
* of the GNU General Public License as published by the Free Software Found-
* ation, either version 3 of the License, or (at your option) any later version.
*
* RetroArch 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along with RetroArch.
* If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <rhash.h>
#include <retro_endianness.h>
#include "general.h"
struct bsv_movie
{
FILE *file;
/* A ring buffer keeping track of positions
* in the file for each frame. */
size_t *frame_pos;
size_t frame_mask;
size_t frame_ptr;
size_t min_file_pos;
size_t state_size;
uint8_t *state;
bool playback;
bool first_rewind;
bool did_rewind;
};
static bool init_playback(bsv_movie_t *handle, const char *path)
{
uint32_t state_size;
uint32_t header[4] = {0};
global_t *global = global_get_ptr();
handle->playback = true;
handle->file = fopen(path, "rb");
if (!handle->file)
{
RARCH_ERR("Couldn't open BSV file \"%s\" for playback.\n", path);
return false;
}
if (fread(header, sizeof(uint32_t), 4, handle->file) != 4)
{
RARCH_ERR("Couldn't read movie header.\n");
return false;
}
/* Compatibility with old implementation that
* used incorrect documentation. */
if (swap_if_little32(header[MAGIC_INDEX]) != BSV_MAGIC
&& swap_if_big32(header[MAGIC_INDEX]) != BSV_MAGIC)
{
RARCH_ERR("Movie file is not a valid BSV1 file.\n");
return false;
}
if (swap_if_big32(header[CRC_INDEX]) != global->content_crc)
RARCH_WARN("CRC32 checksum mismatch between content file and saved content checksum in replay file header; replay highly likely to desync on playback.\n");
state_size = swap_if_big32(header[STATE_SIZE_INDEX]);
if (state_size)
{
handle->state = (uint8_t*)malloc(state_size);
handle->state_size = state_size;
if (!handle->state)
return false;
if (fread(handle->state, 1, state_size, handle->file) != state_size)
{
RARCH_ERR("Couldn't read state from movie.\n");
return false;
}
if (core.retro_serialize_size() == state_size)
core.retro_unserialize(handle->state, state_size);
else
RARCH_WARN("Movie format seems to have a different serializer version. Will most likely fail.\n");
}
handle->min_file_pos = sizeof(header) + state_size;
return true;
}
static bool init_record(bsv_movie_t *handle, const char *path)
{
uint32_t state_size;
uint32_t header[4] = {0};
global_t *global = global_get_ptr();
handle->file = fopen(path, "wb");
if (!handle->file)
{
RARCH_ERR("Couldn't open BSV \"%s\" for recording.\n", path);
return false;
}
/* This value is supposed to show up as
* BSV1 in a HEX editor, big-endian. */
header[MAGIC_INDEX] = swap_if_little32(BSV_MAGIC);
header[CRC_INDEX] = swap_if_big32(global->content_crc);
state_size = core.retro_serialize_size();
header[STATE_SIZE_INDEX] = swap_if_big32(state_size);
fwrite(header, 4, sizeof(uint32_t), handle->file);
handle->min_file_pos = sizeof(header) + state_size;
handle->state_size = state_size;
if (state_size)
{
handle->state = (uint8_t*)malloc(state_size);
if (!handle->state)
return false;
core.retro_serialize(handle->state, state_size);
fwrite(handle->state, 1, state_size, handle->file);
}
return true;
}
void bsv_movie_free(bsv_movie_t *handle)
{
if (!handle)
return;
if (handle->file)
fclose(handle->file);
free(handle->state);
free(handle->frame_pos);
free(handle);
}
bool bsv_movie_get_input(bsv_movie_t *handle, int16_t *input)
{
if (fread(input, sizeof(int16_t), 1, handle->file) != 1)
return false;
*input = swap_if_big16(*input);
return true;
}
void bsv_movie_set_input(bsv_movie_t *handle, int16_t input)
{
input = swap_if_big16(input);
fwrite(&input, sizeof(int16_t), 1, handle->file);
}
bsv_movie_t *bsv_movie_init(const char *path, enum rarch_movie_type type)
{
bsv_movie_t *handle = (bsv_movie_t*)calloc(1, sizeof(*handle));
if (!handle)
return NULL;
if (type == RARCH_MOVIE_PLAYBACK)
{
if (!init_playback(handle, path))
goto error;
}
else if (!init_record(handle, path))
goto error;
/* Just pick something really large
* ~1 million frames rewind should do the trick. */
if (!(handle->frame_pos = (size_t*)calloc((1 << 20), sizeof(size_t))))
goto error;
handle->frame_pos[0] = handle->min_file_pos;
handle->frame_mask = (1 << 20) - 1;
return handle;
error:
bsv_movie_free(handle);
return NULL;
}
void bsv_movie_set_frame_start(bsv_movie_t *handle)
{
if (!handle)
return;
handle->frame_pos[handle->frame_ptr] = ftell(handle->file);
}
void bsv_movie_set_frame_end(bsv_movie_t *handle)
{
if (!handle)
return;
handle->frame_ptr = (handle->frame_ptr + 1) & handle->frame_mask;
handle->first_rewind = !handle->did_rewind;
handle->did_rewind = false;
}
void bsv_movie_frame_rewind(bsv_movie_t *handle)
{
handle->did_rewind = true;
if ((handle->frame_ptr <= 1) && (handle->frame_pos[0] == handle->min_file_pos))
{
/* If we're at the beginning... */
handle->frame_ptr = 0;
fseek(handle->file, handle->min_file_pos, SEEK_SET);
}
else
{
/* First time rewind is performed, the old frame is simply replayed.
* However, playing back that frame caused us to read data, and push
* data to the ring buffer.
*
* Sucessively rewinding frames, we need to rewind past the read data,
* plus another. */
handle->frame_ptr = (handle->frame_ptr -
(handle->first_rewind ? 1 : 2)) & handle->frame_mask;
fseek(handle->file, handle->frame_pos[handle->frame_ptr], SEEK_SET);
}
if (ftell(handle->file) <= (long)handle->min_file_pos)
{
/* We rewound past the beginning. */
if (!handle->playback)
{
/* If recording, we simply reset
* the starting point. Nice and easy. */
fseek(handle->file, 4 * sizeof(uint32_t), SEEK_SET);
core.retro_serialize(handle->state, handle->state_size);
fwrite(handle->state, 1, handle->state_size, handle->file);
}
else
fseek(handle->file, handle->min_file_pos, SEEK_SET);
}
}