o cleanup

tools/bsnes/cheat/cheat.cpp

@@ -0,0 +1,392 @@
+#include <../base.hpp>
+
+Cheat cheat;
+
+Cheat::cheat_t& Cheat::cheat_t::operator=(const Cheat::cheat_t& source) {
+  enabled = source.enabled;
+  code = source.code;
+  desc = source.desc;
+  count = source.count;
+
+  addr.reset();
+  data.reset();
+  for(unsigned n = 0; n < count; n++) {
+    addr[n] = source.addr[n];
+    data[n] = source.data[n];
+  }
+
+  return *this;
+}
+
+//used to sort cheat code list by description
+bool Cheat::cheat_t::operator<(const Cheat::cheat_t& source) {
+  return strcmp(desc, source.desc) < 0;
+}
+
+//parse item ("0123-4567+89AB-CDEF"), return cheat_t item
+//return true if code is valid, false otherwise
+bool Cheat::decode(const char *s, Cheat::cheat_t &item) const {
+  item.enabled = false;
+  item.count = 0;
+
+  lstring list;
+  list.split("+", s);
+
+  for(unsigned n = 0; n < list.size(); n++) {
+    unsigned addr;
+    uint8_t data;
+    type_t type;
+    if(decode(list[n], addr, data, type) == false) return false;
+
+    item.addr[item.count] = addr;
+    item.data[item.count] = data;
+    item.count++;
+  }
+
+  return true;
+}
+
+//read() is used by MemBus::read() if Cheat::enabled(addr) returns true to look up cheat code.
+//returns true if cheat code was found, false if it was not.
+//when true, cheat code substitution value is stored in data.
+bool Cheat::read(unsigned addr, uint8_t &data) const {
+  addr = mirror_address(addr);
+  for(unsigned i = 0; i < code.size(); i++) {
+    if(enabled(i) == false) continue;
+
+    for(unsigned n = 0; n < code[i].count; n++) {
+      if(addr == mirror_address(code[i].addr[n])) {
+        data = code[i].data[n];
+        return true;
+      }
+    }
+  }
+
+  //code not found, or code is disabled
+  return false;
+}
+
+//==============
+//master control
+//==============
+
+//global cheat system enable/disable:
+//if disabled, *all* cheat codes are disabled;
+//otherwise only individually disabled codes are.
+
+bool Cheat::enabled() const {
+  return cheat_system_enabled;
+}
+
+void Cheat::enable() {
+  cheat_system_enabled = true;
+  cheat_enabled = (cheat_system_enabled && cheat_enabled_code_exists);
+}
+
+void Cheat::disable() {
+  cheat_system_enabled = false;
+  cheat_enabled = false;
+}
+
+//================================
+//cheat list manipulation routines
+//================================
+
+bool Cheat::add(bool enable, const char *code_, const char *desc_) {
+  cheat_t item;
+  if(decode(code_, item) == false) return false;
+
+  unsigned i = code.size();
+  code[i] = item;
+  code[i].enabled = enable;
+  code[i].desc = desc_;
+  code[i].code = code_;
+  encode_description(code[i].desc);
+  update(code[i]);
+
+  update_cheat_status();
+  return true;
+}
+
+bool Cheat::edit(unsigned i, bool enable, const char *code_, const char *desc_) {
+  cheat_t item;
+  if(decode(code_, item) == false) return false;
+
+  //disable current code and clear from code lookup table
+  code[i].enabled = false;
+  update(code[i]);
+
+  code[i] = item;
+  code[i].enabled = enable;
+  code[i].desc = desc_;
+  code[i].code = code_;
+  encode_description(code[i].desc);
+  update(code[i]);
+
+  update_cheat_status();
+  return true;
+}
+
+bool Cheat::remove(unsigned i) {
+  unsigned size = code.size();
+  if(i >= size) return false;  //also verifies size cannot be < 1
+
+  for(unsigned n = i; n < size - 1; n++) code[n] = code[n + 1];
+  code.resize(size - 1);
+
+  update_cheat_status();
+  return true;
+}
+
+bool Cheat::get(unsigned i, cheat_t &item) const {
+  if(i >= code.size()) return false;
+
+  item = code[i];
+  decode_description(item.desc);
+  return true;
+}
+
+//==============================
+//cheat status modifier routines
+//==============================
+
+bool Cheat::enabled(unsigned i) const {
+  return (i < code.size() ? code[i].enabled : false);
+}
+
+void Cheat::enable(unsigned i) {
+  if(i >= code.size()) return;
+
+  code[i].enabled = true;
+  update(code[i]);
+  update_cheat_status();
+}
+
+void Cheat::disable(unsigned i) {
+  if(i >= code.size()) return;
+
+  code[i].enabled = false;
+  update(code[i]);
+  update_cheat_status();
+}
+
+//===============================
+//cheat file load / save routines
+//
+//file format:
+//"description", status, nnnn-nnnn[+nnnn-nnnn...]\r\n
+//...
+//===============================
+
+bool Cheat::load(const char *fn) {
+  string data;
+  if(!data.readfile(fn)) return false;
+  data.replace("\r\n", "\n");
+  data.qreplace(" ", "");
+
+  lstring line;
+  line.split("\n", data);
+  for(unsigned i = 0; i < line.size(); i++) {
+    lstring part;
+    part.qsplit(",", line[i]);
+    if(part.size() != 3) continue;
+    trim(part[0], "\"");
+    add(part[1] == "enabled", /* code = */ part[2], /* desc = */ part[0]);
+  }
+
+  return true;
+}
+
+bool Cheat::save(const char *fn) const {
+  file fp;
+  if(!fp.open(fn, file::mode_write)) return false;
+  for(unsigned i = 0; i < code.size(); i++) {
+    fp.print(string()
+      << "\"" << code[i].desc << "\", "
+      << (code[i].enabled ? "enabled, " : "disabled, ")
+      << code[i].code << "\r\n");
+  }
+  fp.close();
+  return true;
+}
+
+void Cheat::clear() {
+  cheat_enabled_code_exists = false;
+  memset(mask, 0, 0x200000);
+  code.reset();
+}
+
+Cheat::Cheat() : cheat_system_enabled(true) {
+  clear();
+}
+
+//==================
+//internal functions
+//==================
+
+//string <> binary code translation routines
+//decode() "7e123456" -> 0x7e123456
+//encode() 0x7e123456 -> "7e123456"
+
+bool Cheat::decode(const char *s, unsigned &addr, uint8_t &data, type_t &type) const {
+  string t = s;
+  strlower(t);
+
+  #define ischr(n) ((n >= '0' && n <= '9') || (n >= 'a' && n <= 'f'))
+
+  if(strlen(t) == 8 || (strlen(t) == 9 && t[6] == ':')) {
+    //strip ':'
+    if(strlen(t) == 9 && t[6] == ':') t = string() << substr(t, 0, 6) << substr(t, 7);
+    //validate input
+    for(unsigned i = 0; i < 8; i++) if(!ischr(t[i])) return false;
+
+    type = ProActionReplay;
+    unsigned r = strhex((const char*)t);
+    addr = r >> 8;
+    data = r & 0xff;
+    return true;
+  } else if(strlen(t) == 9 && t[4] == '-') {
+    //strip '-'
+    t = string() << substr(t, 0, 4) << substr(t, 5);
+    //validate input
+    for(unsigned i = 0; i < 8; i++) if(!ischr(t[i])) return false;
+
+    type = GameGenie;
+    strtr(t, "df4709156bc8a23e", "0123456789abcdef");
+    unsigned r = strhex((const char*)t);
+    //8421 8421 8421 8421 8421 8421
+    //abcd efgh ijkl mnop qrst uvwx
+    //ijkl qrst opab cduv wxef ghmn
+    addr = (!!(r & 0x002000) << 23) | (!!(r & 0x001000) << 22)
+         | (!!(r & 0x000800) << 21) | (!!(r & 0x000400) << 20)
+         | (!!(r & 0x000020) << 19) | (!!(r & 0x000010) << 18)
+         | (!!(r & 0x000008) << 17) | (!!(r & 0x000004) << 16)
+         | (!!(r & 0x800000) << 15) | (!!(r & 0x400000) << 14)
+         | (!!(r & 0x200000) << 13) | (!!(r & 0x100000) << 12)
+         | (!!(r & 0x000002) << 11) | (!!(r & 0x000001) << 10)
+         | (!!(r & 0x008000) <<  9) | (!!(r & 0x004000) <<  8)
+         | (!!(r & 0x080000) <<  7) | (!!(r & 0x040000) <<  6)
+         | (!!(r & 0x020000) <<  5) | (!!(r & 0x010000) <<  4)
+         | (!!(r & 0x000200) <<  3) | (!!(r & 0x000100) <<  2)
+         | (!!(r & 0x000080) <<  1) | (!!(r & 0x000040) <<  0);
+    data = r >> 24;
+    return true;
+  } else {
+    return false;
+  }
+}
+
+bool Cheat::encode(string &s, unsigned addr, uint8_t data, type_t type) const {
+  char t[16];
+
+  if(type == ProActionReplay) {
+    sprintf(t, "%.6x%.2x", addr, data);
+    s = t;
+    return true;
+  } else if(type == GameGenie) {
+    unsigned r = addr;
+    addr = (!!(r & 0x008000) << 23) | (!!(r & 0x004000) << 22)
+         | (!!(r & 0x002000) << 21) | (!!(r & 0x001000) << 20)
+         | (!!(r & 0x000080) << 19) | (!!(r & 0x000040) << 18)
+         | (!!(r & 0x000020) << 17) | (!!(r & 0x000010) << 16)
+         | (!!(r & 0x000200) << 15) | (!!(r & 0x000100) << 14)
+         | (!!(r & 0x800000) << 13) | (!!(r & 0x400000) << 12)
+         | (!!(r & 0x200000) << 11) | (!!(r & 0x100000) << 10)
+         | (!!(r & 0x000008) <<  9) | (!!(r & 0x000004) <<  8)
+         | (!!(r & 0x000002) <<  7) | (!!(r & 0x000001) <<  6)
+         | (!!(r & 0x080000) <<  5) | (!!(r & 0x040000) <<  4)
+         | (!!(r & 0x020000) <<  3) | (!!(r & 0x010000) <<  2)
+         | (!!(r & 0x000800) <<  1) | (!!(r & 0x000400) <<  0);
+    sprintf(t, "%.2x%.2x-%.4x", data, addr >> 16, addr & 0xffff);
+    strtr(t, "0123456789abcdef", "df4709156bc8a23e");
+    s = t;
+    return true;
+  } else {
+    return false;
+  }
+}
+
+//speed up S-CPU memory reads by disabling cheat code lookup when either:
+//a) cheat system is disabled by user, or b) no enabled cheat codes exist
+void Cheat::update_cheat_status() {
+  for(unsigned i = 0; i < code.size(); i++) {
+    if(code[i].enabled) {
+      cheat_enabled_code_exists = true;
+      cheat_enabled = (cheat_system_enabled && cheat_enabled_code_exists);
+      return;
+    }
+  }
+  cheat_enabled_code_exists = false;
+  cheat_enabled = false;
+}
+
+//address lookup table manipulation and mirroring
+//mirror_address() 0x000000 -> 0x7e0000
+//set() enable specified address, mirror accordingly
+//clear() disable specified address, mirror accordingly
+unsigned Cheat::mirror_address(unsigned addr) const {
+  if((addr & 0x40e000) != 0x0000) return addr;
+  //8k WRAM mirror
+  //$[00-3f|80-bf]:[0000-1fff] -> $7e:[0000-1fff]
+  return (0x7e0000 + (addr & 0x1fff));
+}
+
+//updates mask[] table enabled bits;
+//must be called after modifying item.enabled state.
+void Cheat::update(const cheat_t &item) {
+  for(unsigned n = 0; n < item.count; n++) {
+    (item.enabled) ? set(item.addr[n]) : clear(item.addr[n]);
+  }
+}
+
+void Cheat::set(unsigned addr) {
+  addr = mirror_address(addr);
+
+  mask[addr >> 3] |= 1 << (addr & 7);
+  if((addr & 0xffe000) == 0x7e0000) {
+    //mirror $7e:[0000-1fff] to $[00-3f|80-bf]:[0000-1fff]
+    unsigned mirror;
+    for(unsigned x = 0; x <= 0x3f; x++) {
+      mirror = ((0x00 + x) << 16) + (addr & 0x1fff);
+      mask[mirror >> 3] |= 1 << (mirror & 7);
+      mirror = ((0x80 + x) << 16) + (addr & 0x1fff);
+      mask[mirror >> 3] |= 1 << (mirror & 7);
+    }
+  }
+}
+
+void Cheat::clear(unsigned addr) {
+  addr = mirror_address(addr);
+
+  //if there is more than one cheat code using the same address,
+  //(eg with a different override value) then do not clear code
+  //lookup table entry.
+  uint8_t r;
+  if(read(addr, r) == true) return;
+
+  mask[addr >> 3] &= ~(1 << (addr & 7));
+  if((addr & 0xffe000) == 0x7e0000) {
+    //mirror $7e:[0000-1fff] to $[00-3f|80-bf]:[0000-1fff]
+    unsigned mirror;
+    for(unsigned x = 0; x <= 0x3f; x++) {
+      mirror = ((0x00 + x) << 16) + (addr & 0x1fff);
+      mask[mirror >> 3] &= ~(1 << (mirror & 7));
+      mirror = ((0x80 + x) << 16) + (addr & 0x1fff);
+      mask[mirror >> 3] &= ~(1 << (mirror & 7));
+    }
+  }
+}
+
+//these two functions are used to safely store description text inside .cfg file format.
+
+string& Cheat::encode_description(string &desc) const {
+  desc.replace("\"", "\\q");
+  desc.replace("\n", "\\n");
+  return desc;
+}
+
+string& Cheat::decode_description(string &desc) const {
+  desc.replace("\\q", "\"");
+  desc.replace("\\n", "\n");
+  return desc;
+}