/* RetroArch - A frontend for libretro. * Copyright (C) 2010-2014 - Hans-Kristian Arntzen * Copyright (C) 2011-2017 - Daniel De Matteis * Copyright (C) 2014-2017 - Alfred Agrell * * 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 . */ #ifndef __STDC_LIMIT_MACROS #define __STDC_LIMIT_MACROS #endif #include #include #include #include #include #include #include "state_manager.h" #include "msg_hash.h" #include "core.h" #include "core_info.h" #include "retroarch.h" #include "verbosity.h" #include "content.h" #include "audio/audio_driver.h" #ifdef HAVE_NETWORKING #include "network/netplay/netplay.h" #endif /* This makes Valgrind throw errors if a core overflows its savestate size. */ /* Keep it off unless you're chasing a core bug, it slows things down. */ #define STRICT_BUF_SIZE 0 #ifndef UINT16_MAX #define UINT16_MAX 0xffff #endif #ifndef UINT32_MAX #define UINT32_MAX 0xffffffffu #endif #if defined(__x86_64__) || defined(__i386__) || defined(__i486__) || defined(__i686__) || defined(_M_IX86) || defined(_M_AMD64) || defined(_M_X64) #define CPU_X86 #endif /* Other arches SIGBUS (usually) on unaligned accesses. */ #ifndef CPU_X86 #define NO_UNALIGNED_MEM #endif #if __SSE2__ #include #endif /* Format per frame (pseudocode): */ #if 0 size nextstart; repeat { uint16 numchanged; /* everything is counted in units of uint16 */ if (numchanged) { uint16 numunchanged; /* skip these before handling numchanged */ uint16[numchanged] changeddata; } else { uint32 numunchanged; if (!numunchanged) break; } } size thisstart; #endif /* There's no equivalent in libc, you'd think so ... * std::mismatch exists, but it's not optimized at all. */ static size_t find_change(const uint16_t *a, const uint16_t *b) { #if __SSE2__ const __m128i *a128 = (const __m128i*)a; const __m128i *b128 = (const __m128i*)b; for (;;) { __m128i v0 = _mm_loadu_si128(a128); __m128i v1 = _mm_loadu_si128(b128); __m128i c = _mm_cmpeq_epi8(v0, v1); uint32_t mask = _mm_movemask_epi8(c); if (mask != 0xffff) /* Something has changed, figure out where. */ { /* calculate the real offset to the differing byte */ size_t ret = (((uint8_t*)a128 - (uint8_t*)a) | (compat_ctz(~mask))); /* and convert that to the uint16_t offset */ return (ret >> 1); } a128++; b128++; } #else const uint16_t *a_org = a; #ifdef NO_UNALIGNED_MEM while (((uintptr_t)a & (sizeof(size_t) - 1)) && *a == *b) { a++; b++; } if (*a == *b) #endif { const size_t *a_big = (const size_t*)a; const size_t *b_big = (const size_t*)b; while (*a_big == *b_big) { a_big++; b_big++; } a = (const uint16_t*)a_big; b = (const uint16_t*)b_big; while (*a == *b) { a++; b++; } } return a - a_org; #endif } static size_t find_same(const uint16_t *a, const uint16_t *b) { const uint16_t *a_org = a; #ifdef NO_UNALIGNED_MEM if (((uintptr_t)a & (sizeof(uint32_t) - 1)) && *a != *b) { a++; b++; } if (*a != *b) #endif { /* With this, it's random whether two consecutive identical * words are caught. * * Luckily, compression rate is the same for both cases, and * three is always caught. * * (We prefer to miss two-word blocks, anyways; fewer iterations * of the outer loop, as well as in the decompressor.) */ const uint32_t *a_big = (const uint32_t*)a; const uint32_t *b_big = (const uint32_t*)b; while (*a_big != *b_big) { a_big++; b_big++; } a = (const uint16_t*)a_big; b = (const uint16_t*)b_big; if (a != a_org && a[-1] == b[-1]) { a--; b--; } } return a - a_org; } /* Returns the maximum compressed size of a savestate. * It is very likely to compress to far less. */ static size_t state_manager_raw_maxsize(size_t uncomp) { /* bytes covered by a compressed block */ const int maxcblkcover = UINT16_MAX * sizeof(uint16_t); /* uncompressed size, rounded to 16 bits */ size_t uncomp16 = (uncomp + sizeof(uint16_t) - 1) & -sizeof(uint16_t); /* number of blocks */ size_t maxcblks = (uncomp + maxcblkcover - 1) / maxcblkcover; return uncomp16 + maxcblks * sizeof(uint16_t) * 2 /* two u16 overhead per block */ + sizeof(uint16_t) * 3; /* three u16 to end it */ } /* * See state_manager_raw_compress for information about this. * When you're done with it, send it to free(). */ static void *state_manager_raw_alloc(size_t len, uint16_t uniq) { size_t len16 = (len + sizeof(uint16_t) - 1) & -sizeof(uint16_t); uint16_t *ret = (uint16_t*)calloc(len16 + sizeof(uint16_t) * 4 + 16, 1); if (!ret) return NULL; /* Force in a different byte at the end, so we don't need to check * bounds in the innermost loop (it's expensive). * * There is also a large amount of data that's the same, to stop * the other scan. * * There is also some padding at the end. This is so we don't * read outside the buffer end if we're reading in large blocks; * * It doesn't make any difference to us, but sacrificing 16 bytes to get * Valgrind happy is worth it. */ ret[len16/sizeof(uint16_t) + 3] = uniq; return ret; } /* * Takes two savestates and creates a patch that turns 'src' into 'dst'. * Both 'src' and 'dst' must be returned from state_manager_raw_alloc(), * with the same 'len', and different 'uniq'. * * 'patch' must be size 'state_manager_raw_maxsize(len)' or more. * Returns the number of bytes actually written to 'patch'. */ static size_t state_manager_raw_compress(const void *src, const void *dst, size_t len, void *patch) { const uint16_t *old16 = (const uint16_t*)src; const uint16_t *new16 = (const uint16_t*)dst; uint16_t *compressed16 = (uint16_t*)patch; size_t num16s = (len + sizeof(uint16_t) - 1) / sizeof(uint16_t); while (num16s) { size_t i, changed; size_t skip = find_change(old16, new16); if (skip >= num16s) break; old16 += skip; new16 += skip; num16s -= skip; if (skip > UINT16_MAX) { /* This will make it scan the entire thing again, * but it only hits on 8GB unchanged data anyways, * and if you're doing that, you've got bigger problems. */ if (skip > UINT32_MAX) skip = UINT32_MAX; *compressed16++ = 0; *compressed16++ = skip; *compressed16++ = skip >> 16; continue; } changed = find_same(old16, new16); if (changed > UINT16_MAX) changed = UINT16_MAX; *compressed16++ = changed; *compressed16++ = skip; for (i = 0; i < changed; i++) compressed16[i] = old16[i]; old16 += changed; new16 += changed; num16s -= changed; compressed16 += changed; } compressed16[0] = 0; compressed16[1] = 0; compressed16[2] = 0; return (uint8_t*)(compressed16 + 3) - (uint8_t*)patch; } /* * Takes 'patch' from a previous call to 'state_manager_raw_compress' * and applies it to 'data' ('src' from that call), * yielding 'dst' in that call. * * If the given arguments do not match a previous call to * state_manager_raw_compress(), anything at all can happen. */ static void state_manager_raw_decompress(const void *patch, size_t patchlen, void *data, size_t datalen) { uint16_t *out16 = (uint16_t*)data; const uint16_t *patch16 = (const uint16_t*)patch; for (;;) { uint16_t numchanged = *(patch16++); if (numchanged) { uint16_t i; out16 += *patch16++; /* We could do memcpy, but it seems that memcpy has a * constant-per-call overhead that actually shows up. * * Our average size in here seems to be 8 or something. * Therefore, we do something with lower overhead. */ for (i = 0; i < numchanged; i++) out16[i] = patch16[i]; patch16 += numchanged; out16 += numchanged; } else { uint32_t numunchanged = patch16[0] | (patch16[1] << 16); if (!numunchanged) break; patch16 += 2; out16 += numunchanged; } } } /* The start offsets point to 'nextstart' of any given compressed frame. * Each uint16 is stored native endian; anything that claims any other * endianness refers to the endianness of this specific item. * The uint32 is stored little endian. * * Each size value is stored native endian if alignment is not enforced; * if it is, they're little endian. * * The start of the buffer contains a size pointing to the end of the * buffer; the end points to its start. * * Wrapping is handled by returning to the start of the buffer if the * compressed data could potentially hit the edge; * * if the compressed data could potentially overwrite the tail pointer, * the tail retreats until it can no longer collide. * * This means that on average, ~2 * maxcompsize is * unused at any given moment. */ /* These are called very few constant times per frame, * keep it as simple as possible. */ static INLINE void write_size_t(void *ptr, size_t val) { memcpy(ptr, &val, sizeof(val)); } static INLINE size_t read_size_t(const void *ptr) { size_t ret; memcpy(&ret, ptr, sizeof(ret)); return ret; } static void state_manager_free(state_manager_t *state) { if (!state) return; if (state->data) free(state->data); if (state->thisblock) free(state->thisblock); if (state->nextblock) free(state->nextblock); #if STRICT_BUF_SIZE if (state->debugblock) free(state->debugblock); state->debugblock = NULL; #endif state->data = NULL; state->thisblock = NULL; state->nextblock = NULL; } static state_manager_t *state_manager_new( size_t state_size, size_t buffer_size) { size_t max_comp_size, block_size; uint8_t *next_block = NULL; uint8_t *this_block = NULL; uint8_t *state_data = NULL; state_manager_t *state = (state_manager_t*)calloc(1, sizeof(*state)); if (!state) return NULL; block_size = (state_size + sizeof(uint16_t) - 1) & -sizeof(uint16_t); /* the compressed data is surrounded by pointers to the other side */ max_comp_size = state_manager_raw_maxsize(state_size) + sizeof(size_t) * 2; state_data = (uint8_t*)malloc(buffer_size); if (!state_data) goto error; this_block = (uint8_t*)state_manager_raw_alloc(state_size, 0); next_block = (uint8_t*)state_manager_raw_alloc(state_size, 1); if (!this_block || !next_block) goto error; state->blocksize = block_size; state->maxcompsize = max_comp_size; state->data = state_data; state->thisblock = this_block; state->nextblock = next_block; state->capacity = buffer_size; state->head = state->data + sizeof(size_t); state->tail = state->data + sizeof(size_t); #if STRICT_BUF_SIZE state->debugsize = state_size; state->debugblock = (uint8_t*)malloc(state_size); #endif return state; error: if (state_data) free(state_data); state_manager_free(state); free(state); return NULL; } static bool state_manager_pop(state_manager_t *state, const void **data) { size_t start; uint8_t *out = NULL; const uint8_t *compressed = NULL; *data = NULL; if (state->thisblock_valid) { state->thisblock_valid = false; state->entries--; *data = state->thisblock; return true; } *data = state->thisblock; if (state->head == state->tail) return false; start = read_size_t(state->head - sizeof(size_t)); state->head = state->data + start; compressed = state->data + start + sizeof(size_t); out = state->thisblock; state_manager_raw_decompress(compressed, state->maxcompsize, out, state->blocksize); state->entries--; return true; } static void state_manager_push_where(state_manager_t *state, void **data) { /* We need to ensure we have an uncompressed copy of the last * pushed state, or we could end up applying a 'patch' to wrong * savestate, and that'd blow up rather quickly. */ if (!state->thisblock_valid) { const void *ignored; if (state_manager_pop(state, &ignored)) { state->thisblock_valid = true; state->entries++; } } *data = state->nextblock; #if STRICT_BUF_SIZE *data = state->debugblock; #endif } static void state_manager_push_do(state_manager_t *state) { uint8_t *swap = NULL; #if STRICT_BUF_SIZE memcpy(state->nextblock, state->debugblock, state->debugsize); #endif if (state->thisblock_valid) { const uint8_t *oldb, *newb; uint8_t *compressed; size_t headpos, tailpos, remaining; if (state->capacity < sizeof(size_t) + state->maxcompsize) { RARCH_ERR("State capacity insufficient\n"); return; } recheckcapacity:; headpos = state->head - state->data; tailpos = state->tail - state->data; remaining = (tailpos + state->capacity - sizeof(size_t) - headpos - 1) % state->capacity + 1; if (remaining <= state->maxcompsize) { state->tail = state->data + read_size_t(state->tail); state->entries--; goto recheckcapacity; } oldb = state->thisblock; newb = state->nextblock; compressed = state->head + sizeof(size_t); compressed += state_manager_raw_compress(oldb, newb, state->blocksize, compressed); if (compressed - state->data + state->maxcompsize > state->capacity) { compressed = state->data; if (state->tail == state->data + sizeof(size_t)) state->tail = state->data + read_size_t(state->tail); } write_size_t(compressed, state->head-state->data); compressed += sizeof(size_t); write_size_t(state->head, compressed-state->data); state->head = compressed; } else state->thisblock_valid = true; swap = state->thisblock; state->thisblock = state->nextblock; state->nextblock = swap; state->entries++; } #if 0 static void state_manager_capacity(state_manager_t *state, unsigned *entries, size_t *bytes, bool *full) { size_t headpos = state->head - state->data; size_t tailpos = state->tail - state->data; size_t remaining = (tailpos + state->capacity - sizeof(size_t) - headpos - 1) % state->capacity + 1; if (entries) *entries = state->entries; if (bytes) *bytes = state->capacity-remaining; if (full) *full = remaining <= state->maxcompsize * 2; } #endif void state_manager_event_init( struct state_manager_rewind_state *rewind_st, unsigned rewind_buffer_size) { core_info_t *core_info = NULL; void *state = NULL; if ( !rewind_st || (rewind_st->flags & STATE_MGR_REWIND_ST_FLAG_INIT_ATTEMPTED) || rewind_st->state) return; rewind_st->size = 0; rewind_st->flags &= ~( STATE_MGR_REWIND_ST_FLAG_FRAME_IS_REVERSED | STATE_MGR_REWIND_ST_FLAG_HOTKEY_WAS_CHECKED | STATE_MGR_REWIND_ST_FLAG_HOTKEY_WAS_PRESSED ); /* We cannot initialise the rewind buffer * unless the core info struct for the current * core has been initialised (i.e. without this, * the savestate support level for the current * core is unknown) */ if (!core_info_get_current_core(&core_info) || !core_info) return; rewind_st->flags |= STATE_MGR_REWIND_ST_FLAG_INIT_ATTEMPTED; if (!core_info_current_supports_rewind()) { RARCH_ERR("%s\n", msg_hash_to_str(MSG_REWIND_UNSUPPORTED)); return; } if (audio_driver_has_callback()) { RARCH_ERR("%s.\n", msg_hash_to_str(MSG_REWIND_INIT_FAILED_THREADED_AUDIO)); return; } rewind_st->size = content_get_serialized_size_rewind(); if (!rewind_st->size) { RARCH_ERR("%s.\n", msg_hash_to_str(MSG_REWIND_INIT_FAILED)); return; } RARCH_LOG("%s: %u MB\n", msg_hash_to_str(MSG_REWIND_INIT), (unsigned)(rewind_buffer_size / 1000000)); rewind_st->state = state_manager_new(rewind_st->size, rewind_buffer_size); if (!rewind_st->state) RARCH_WARN("%s.\n", msg_hash_to_str(MSG_REWIND_INIT_FAILED)); state_manager_push_where(rewind_st->state, &state); content_serialize_state_rewind(state, rewind_st->size); state_manager_push_do(rewind_st->state); } void state_manager_event_deinit( struct state_manager_rewind_state *rewind_st, struct retro_core_t *current_core) { bool restore_callbacks = false; if (!rewind_st) return; restore_callbacks = (rewind_st->flags & STATE_MGR_REWIND_ST_FLAG_INIT_ATTEMPTED) && (rewind_st->state) && (current_core); if (rewind_st->state) { state_manager_free(rewind_st->state); free(rewind_st->state); } rewind_st->state = NULL; rewind_st->size = 0; rewind_st->flags &= ~( STATE_MGR_REWIND_ST_FLAG_FRAME_IS_REVERSED | STATE_MGR_REWIND_ST_FLAG_HOTKEY_WAS_CHECKED | STATE_MGR_REWIND_ST_FLAG_HOTKEY_WAS_PRESSED | STATE_MGR_REWIND_ST_FLAG_INIT_ATTEMPTED ); /* Restore regular (non-rewind) core audio * callbacks if required */ if (restore_callbacks) { if (current_core->retro_set_audio_sample) current_core->retro_set_audio_sample(audio_driver_sample); if (current_core->retro_set_audio_sample_batch) current_core->retro_set_audio_sample_batch(audio_driver_sample_batch); } } /** * check_rewind: * @pressed : was rewind key pressed or held? * * Checks if rewind toggle/hold was being pressed and/or held. **/ bool state_manager_check_rewind( struct state_manager_rewind_state *rewind_st, struct retro_core_t *current_core, bool pressed, unsigned rewind_granularity, bool is_paused, char *s, size_t len, unsigned *time) { bool ret = false; #ifdef HAVE_NETWORKING bool was_reversed = false; #endif if ( !rewind_st || (!(rewind_st->flags & STATE_MGR_REWIND_ST_FLAG_INIT_ATTEMPTED))) return false; if (!(rewind_st->flags & STATE_MGR_REWIND_ST_FLAG_HOTKEY_WAS_CHECKED)) { rewind_st->flags |= STATE_MGR_REWIND_ST_FLAG_HOTKEY_WAS_CHECKED; return false; } if (!rewind_st->state) { if ((pressed && (!(rewind_st->flags & STATE_MGR_REWIND_ST_FLAG_HOTKEY_WAS_PRESSED))) && !core_info_current_supports_rewind()) runloop_msg_queue_push(msg_hash_to_str(MSG_REWIND_UNSUPPORTED), 1, 100, false, NULL, MESSAGE_QUEUE_ICON_DEFAULT, MESSAGE_QUEUE_CATEGORY_INFO); if (pressed) rewind_st->flags |= STATE_MGR_REWIND_ST_FLAG_HOTKEY_WAS_PRESSED; else rewind_st->flags &= ~STATE_MGR_REWIND_ST_FLAG_HOTKEY_WAS_PRESSED; return false; } if (rewind_st->flags & STATE_MGR_REWIND_ST_FLAG_FRAME_IS_REVERSED) { #ifdef HAVE_NETWORKING was_reversed = true; #endif audio_driver_frame_is_reverse(); rewind_st->flags &= ~STATE_MGR_REWIND_ST_FLAG_FRAME_IS_REVERSED; } if (pressed) { const void *buf = NULL; if (state_manager_pop(rewind_st->state, &buf)) { #ifdef HAVE_NETWORKING /* Make sure netplay isn't confused */ if (!was_reversed && !netplay_driver_ctl(RARCH_NETPLAY_CTL_DESYNC_PUSH, NULL)) return false; #endif rewind_st->flags |= STATE_MGR_REWIND_ST_FLAG_FRAME_IS_REVERSED; audio_driver_setup_rewind(); strlcpy(s, msg_hash_to_str(MSG_REWINDING), len); *time = is_paused ? 1 : 30; ret = true; content_deserialize_state(buf, rewind_st->size); #ifdef HAVE_BSV_MOVIE bsv_movie_frame_rewind(); #endif } else { content_deserialize_state(buf, rewind_st->size); #ifdef HAVE_NETWORKING /* Tell netplay we're done */ if (was_reversed) netplay_driver_ctl(RARCH_NETPLAY_CTL_DESYNC_POP, NULL); #endif strlcpy(s, msg_hash_to_str(MSG_REWIND_REACHED_END), len); *time = 30; ret = true; } } else { static unsigned cnt = 0; #ifdef HAVE_NETWORKING /* Tell netplay we're done */ if (was_reversed) netplay_driver_ctl(RARCH_NETPLAY_CTL_DESYNC_POP, NULL); #endif cnt = (cnt + 1) % (rewind_granularity ? rewind_granularity : 1); /* Avoid possible SIGFPE. */ if ( !is_paused && ((cnt == 0) || retroarch_ctl(RARCH_CTL_BSV_MOVIE_IS_INITED, NULL))) { void *state = NULL; state_manager_push_where(rewind_st->state, &state); content_serialize_state_rewind(state, rewind_st->size); state_manager_push_do(rewind_st->state); } } /* Update core audio callbacks */ if (current_core) { if (current_core->retro_set_audio_sample) current_core->retro_set_audio_sample( (rewind_st->flags & STATE_MGR_REWIND_ST_FLAG_FRAME_IS_REVERSED) ? audio_driver_sample_rewind : audio_driver_sample); if (current_core->retro_set_audio_sample_batch) current_core->retro_set_audio_sample_batch( ( rewind_st->flags & STATE_MGR_REWIND_ST_FLAG_FRAME_IS_REVERSED) ? audio_driver_sample_batch_rewind : audio_driver_sample_batch); } if (pressed) rewind_st->flags |= STATE_MGR_REWIND_ST_FLAG_HOTKEY_WAS_PRESSED; else rewind_st->flags &= ~STATE_MGR_REWIND_ST_FLAG_HOTKEY_WAS_PRESSED; return ret; }