diff options
Diffstat (limited to 'cheats.c')
| -rw-r--r-- | cheats.c | 544 |
1 files changed, 209 insertions, 335 deletions
@@ -19,373 +19,247 @@ #include "common.h" -cheat_type cheats[MAX_CHEATS]; -u32 num_cheats; - -void decrypt_gsa_code(u32 *address_ptr, u32 *value_ptr, cheat_variant_enum - cheat_variant) +typedef struct { - u32 i; - u32 address = *address_ptr; - u32 value = *value_ptr; - u32 r = 0xc6ef3720; - - u32 seeds_v1[4] = - { - 0x09f4fbbd, 0x9681884a, 0x352027e9, 0xf3dee5a7 - }; - u32 seeds_v3[4] = - { - 0x7aa9648f, 0x7fae6994, 0xc0efaad5, 0x42712c57 - }; - u32 *seeds; + bool cheat_active; + struct { + u32 address; + u32 value; + } codes[MAX_CHEAT_CODES]; + unsigned cheat_count; +} cheat_type; - if(cheat_variant == CHEAT_TYPE_GAMESHARK_V1) - seeds = seeds_v1; - else - seeds = seeds_v3; +cheat_type cheats[MAX_CHEATS]; +u32 max_cheat = 0; +u32 cheat_master_hook = 0xffffffff; - for(i = 0; i < 32; i++) +static bool has_encrypted_codebreaker(cheat_type *cheat) +{ + int i; + for(i = 0; i < cheat->cheat_count; i++) { - value -= ((address << 4) + seeds[2]) ^ (address + r) ^ - ((address >> 5) + seeds[3]); - address -= ((value << 4) + seeds[0]) ^ (value + r) ^ - ((value >> 5) + seeds[1]); - r -= 0x9e3779b9; + u32 code = cheat->codes[i].address; + u32 opcode = code >> 28; + if (opcode == 9) + return true; } - - *address_ptr = address; - *value_ptr = value; + return false; } -void add_cheats(char *cheats_filename) +static void update_hook_codebreaker(cheat_type *cheat) { - FILE *cheats_file; - char current_line[256]; - char *name_ptr; - u32 *cheat_code_ptr; - u32 address, value; - u32 num_cheat_lines; - u32 cheat_name_length; - cheat_variant_enum current_cheat_variant; - - num_cheats = 0; - - cheats_file = fopen(cheats_filename, "rb"); - - if(cheats_file) + int i; + for(i = 0; i < cheat->cheat_count; i++) { - while(fgets(current_line, 256, cheats_file)) - { - // Get the header line first - name_ptr = strchr(current_line, ' '); - if(name_ptr) - { - *name_ptr = 0; - name_ptr++; - } - - if(!strcasecmp(current_line, "gameshark_v1") || - !strcasecmp(current_line, "gameshark_v2") || - !strcasecmp(current_line, "PAR_v1") || - !strcasecmp(current_line, "PAR_v2")) - { - current_cheat_variant = CHEAT_TYPE_GAMESHARK_V1; - } - else - - if(!strcasecmp(current_line, "gameshark_v3") || - !strcasecmp(current_line, "PAR_v3")) - { - current_cheat_variant = CHEAT_TYPE_GAMESHARK_V3; - } - else - { - current_cheat_variant = CHEAT_TYPE_INVALID; - } - - if(current_cheat_variant != CHEAT_TYPE_INVALID) - { - strncpy(cheats[num_cheats].cheat_name, name_ptr, CHEAT_NAME_LENGTH - 1); - cheats[num_cheats].cheat_name[CHEAT_NAME_LENGTH - 1] = 0; - cheat_name_length = strlen(cheats[num_cheats].cheat_name); - if(cheat_name_length && - ((cheats[num_cheats].cheat_name[cheat_name_length - 1] == '\n') || - (cheats[num_cheats].cheat_name[cheat_name_length - 1] == '\r'))) - { - cheats[num_cheats].cheat_name[cheat_name_length - 1] = 0; - cheat_name_length--; - } - - if(cheat_name_length && - cheats[num_cheats].cheat_name[cheat_name_length - 1] == '\r') - { - cheats[num_cheats].cheat_name[cheat_name_length - 1] = 0; - } - - cheats[num_cheats].cheat_variant = current_cheat_variant; - cheat_code_ptr = cheats[num_cheats].cheat_codes; - num_cheat_lines = 0; - - while(fgets(current_line, 256, cheats_file)) - { - if(strlen(current_line) < 3) - break; - - sscanf(current_line, "%08x %08x", &address, &value); - - decrypt_gsa_code(&address, &value, current_cheat_variant); - - cheat_code_ptr[0] = address; - cheat_code_ptr[1] = value; - - cheat_code_ptr += 2; - num_cheat_lines++; - } - - cheats[num_cheats].num_cheat_lines = num_cheat_lines; - - num_cheats++; - } - } - - fclose(cheats_file); + u32 code = cheat->codes[i].address; + u32 address = code & 0xfffffff; + u32 opcode = code >> 28; + + if (opcode == 1) + { + u32 pcaddr = 0x08000000 | (address & 0x1ffffff); + #ifdef HAVE_DYNAREC + if (cheat_master_hook != pcaddr) + init_caches(); /* Flush caches to install hook */ + #endif + cheat_master_hook = pcaddr; + return; /* Only support for one hook */ + } } } -void process_cheat_gs1(cheat_type *cheat) +static void process_cheat_codebreaker(cheat_type *cheat, u16 pad) { - u32 cheat_opcode; - u32 *code_ptr = cheat->cheat_codes; - u32 address, value; - u32 i; - - for(i = 0; i < cheat->num_cheat_lines; i++) + int i; + unsigned j; + for(i = 0; i < cheat->cheat_count; i++) { - address = code_ptr[0]; - value = code_ptr[1]; - - code_ptr += 2; - - cheat_opcode = address >> 28; - address &= 0xFFFFFFF; - - switch(cheat_opcode) - { - case 0x0: - write_memory8(address, value); - break; - - case 0x1: - write_memory16(address, value); - break; - - case 0x2: - write_memory32(address, value); - break; - - case 0x3: + u32 code = cheat->codes[i].address; + u16 value = cheat->codes[i].value; + u32 address = code & 0xfffffff; + u32 opcode = code >> 28; + + switch (opcode) { + case 0: /* Game CRC, ignored for now */ + break; + case 1: /* Master code function */ + break; + case 2: /* 16 bit OR */ + write_memory16(address, read_memory16(address) | value); + break; + case 3: /* 8 bit write */ + write_memory8(address, value); + break; + case 4: /* Slide code, writes a buffer with addr/value strides */ + if (i + 1 < cheat->cheat_count) { - u32 num_addresses = address & 0xFFFF; - u32 address1, address2; - u32 i2; - - for(i2 = 0; i2 < num_addresses; i2++) + u16 count = cheat->codes[++i].address; + u16 vincr = cheat->codes[ i].address >> 16; + u16 aincr = cheat->codes[ i].value; + for (j = 0; j < count; j++) { - address1 = code_ptr[0]; - address2 = code_ptr[1]; - code_ptr += 2; - i++; - - write_memory32(address1, value); - if(address2 != 0) - write_memory32(address2, value); + write_memory16(address, value); + address += aincr; + value += vincr; } - break; } - - // ROM patch not supported yet - case 0x6: - break; - - // GS button down not supported yet - case 0x8: - break; - - // Reencryption (DEADFACE) not supported yet - case 0xD: - if(read_memory16(address) != (value & 0xFFFF)) - { - code_ptr += 2; + break; + case 5: /* Super code: copies bytes to a buffer addr */ + for (j = 0; j < value * 2 && i < cheat->cheat_count; j++) + { + u8 bvalue, off = j % 6; + switch (off) { + case 0: + bvalue = cheat->codes[++i].address >> 24; + break; + case 1 ... 3: + bvalue = cheat->codes[i].address >> (24 - off*8); + break; + case 4 ... 5: + bvalue = cheat->codes[i].value >> (40 - off*8); + break; + }; + write_memory8(address, bvalue); + address++; + } + break; + case 6: /* 16 bit AND */ + write_memory16(address, read_memory16(address) & value); + break; + case 7: /* Compare mem value and execute next cheat */ + if (read_memory16(address) != value) + i++; + break; + case 8: /* 16 bit write */ + write_memory16(address, value); + break; + case 10: /* Compare mem value and skip next cheat */ + if (read_memory16(address) == value) + i++; + break; + case 11: /* Compare mem value and skip next cheat */ + if (read_memory16(address) <= value) + i++; + break; + case 12: /* Compare mem value and skip next cheat */ + if (read_memory16(address) >= value) + i++; + break; + case 13: /* Check button state and execute next cheat */ + switch ((address >> 4) & 0xf) { + case 0: + if (((~pad) & 0x3ff) == value) i++; - } break; - - case 0xE: - if(read_memory16(value & 0xFFFFFFF) != (address & 0xFFFF)) - { - u32 skip = ((address >> 16) & 0x03); - code_ptr += skip * 2; - i += skip; - } + case 1: + if ((pad & value) == value) + i++; break; - - // Hook routine not supported yet (not important??) - case 0x0F: + case 2: + if ((pad & value) == 0) + i++; break; + }; + break; + case 14: /* Increase 16/32 bit memory value */ + if (address & 1) + { + u32 value32 = (u32)((s16)value); /* Sign extend to 32 bit */ + address &= ~1U; + write_memory32(address, read_memory32(address) + value32); + } + else + { + write_memory16(address, read_memory16(address) + value); + } + break; + case 15: /* Immediate and check and skip */ + if ((read_memory16(address) & value) == 0) + i++; + break; } } } -// These are especially incomplete. - -void process_cheat_gs3(cheat_type *cheat) +void process_cheats(void) { - u32 cheat_opcode; - u32 *code_ptr = cheat->cheat_codes; - u32 address, value; - u32 i; - - for(i = 0; i < cheat->num_cheat_lines; i++) - { - address = code_ptr[0]; - value = code_ptr[1]; - - code_ptr += 2; - - cheat_opcode = address >> 28; - address &= 0xFFFFFFF; - - switch(cheat_opcode) - { - case 0x0: - cheat_opcode = address >> 24; - address = (address & 0xFFFFF) + ((address << 4) & 0xF000000); - - switch(cheat_opcode) - { - case 0x0: - { - u32 iterations = value >> 24; - u32 i2; - - value &= 0xFF; - - for(i2 = 0; i2 <= iterations; i2++, address++) - { - write_memory8(address, value); - } - break; - } - - case 0x2: - { - u32 iterations = value >> 16; - u32 i2; - - value &= 0xFFFF; - - for(i2 = 0; i2 <= iterations; i2++, address += 2) - { - write_memory16(address, value); - } - break; - } - - case 0x4: - write_memory32(address, value); - break; - } - break; - - case 0x4: - cheat_opcode = address >> 24; - address = (address & 0xFFFFF) + ((address << 4) & 0xF000000); - - switch(cheat_opcode) - { - case 0x0: - address = read_memory32(address) + (value >> 24); - write_memory8(address, value & 0xFF); - break; - - case 0x2: - address = read_memory32(address) + ((value >> 16) * 2); - write_memory16(address, value & 0xFFFF); - break; - - case 0x4: - address = read_memory32(address); - write_memory32(address, value); - break; - - } - break; - - case 0x8: - cheat_opcode = address >> 24; - address = (address & 0xFFFFF) + ((address << 4) & 0xF000000); - - switch(cheat_opcode) - { - case 0x0: - value = (value & 0xFF) + read_memory8(address); - write_memory8(address, value); - break; + u32 i; - case 0x2: - value = (value & 0xFFFF) + read_memory16(address); - write_memory16(address, value); - break; + for(i = 0; i <= max_cheat; i++) + { + if(!cheats[i].cheat_active) + continue; - case 0x4: - value = value + read_memory32(address); - write_memory32(address, value); - break; - } - break; - - case 0xC: - cheat_opcode = address >> 24; - address = (address & 0xFFFFFF) + 0x4000000; - - switch(cheat_opcode) - { - case 0x6: - write_memory16(address, value); - break; - - case 0x7: - write_memory32(address, value); - break; - } - break; - } - } + process_cheat_codebreaker(&cheats[i], 0x3ff ^ read_ioreg(REG_P1)); + } } - -void process_cheats(void) +void cheat_clear() { - u32 i; + int i; + for (i = 0; i < MAX_CHEATS; i++) + { + cheats[i].cheat_count = 0; + cheats[i].cheat_active = false; + } + cheat_master_hook = 0xffffffff; +} - for(i = 0; i < num_cheats; i++) - { - if(cheats[i].cheat_active) - { - switch(cheats[i].cheat_variant) - { - case CHEAT_TYPE_GAMESHARK_V1: - process_cheat_gs1(cheats + i); - break; +cheat_error cheat_parse(unsigned index, const char *code) +{ + int pos = 0; + int codelen = strlen(code); + cheat_type *ch = &cheats[index]; + char buf[1024]; + + if (index >= MAX_CHEATS) + return CheatErrorTooMany; + if (codelen >= sizeof(buf)) + return CheatErrorTooBig; + + memcpy(buf, code, codelen+1); + + /* Init to a known good state */ + ch->cheat_count = 0; + if (index > max_cheat) + max_cheat = index; + + /* Replace all the non-hex chars to spaces */ + for (pos = 0; pos < codelen; pos++) + if (!((buf[pos] >= '0' && buf[pos] <= '9') || + (buf[pos] >= 'a' && buf[pos] <= 'f') || + (buf[pos] >= 'A' && buf[pos] <= 'F'))) + buf[pos] = ' '; + + /* Try to parse as Code Breaker */ + pos = 0; + while (pos < codelen) + { + u32 op1; u16 op2; + if (2 != sscanf(&buf[pos], "%08x %04hx", &op1, &op2)) + break; + ch->codes[ch->cheat_count].address = op1; + ch->codes[ch->cheat_count++].value = op2; + pos += 13; + while (pos < codelen && buf[pos] == ' ') + pos++; + if (ch->cheat_count >= MAX_CHEAT_CODES) + break; + } + + if (pos >= codelen) + { + /* Check whether these cheats are readable */ + if (has_encrypted_codebreaker(ch)) + return CheatErrorEncrypted; + /* All codes were parsed! Process hook here */ + ch->cheat_active = true; + update_hook_codebreaker(ch); + return CheatNoError; + } + + /* TODO parse other types here */ + return CheatErrorNotSupported; +} - case CHEAT_TYPE_GAMESHARK_V3: - process_cheat_gs3(cheats + i); - break; - default: - break; - } - } - } -} |