# squirrel.cpp

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    00001 /* $Id$ */
    00002
    00003 /*
    00004  * This file is part of OpenTTD.
    00005  * OpenTTD 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 Foundation, version 2.
    00006  * OpenTTD 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.
    00007  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
    00008  */
    00009
    00012 #include <stdarg.h>
    00013 #include "../stdafx.h"
    00014 #include "../debug.h"
    00015 #include "squirrel_std.hpp"
    00016 #include "../fileio_func.h"
    00017 #include <sqstdaux.h>
    00018 #include <../squirrel/sqpcheader.h>
    00019 #include <../squirrel/sqvm.h>
    00020
    00021 void Squirrel::CompileError(HSQUIRRELVM vm, const SQChar *desc, const SQChar *source, SQInteger line, SQInteger column)
    00022 {
    00023   SQChar buf[1024];
    00024
    00025 #ifdef _SQ64
    00026   scsnprintf(buf, lengthof(buf), _SC("Error %s:%ld/%ld: %s"), source, line, column, desc);
    00027 #else
    00028   scsnprintf(buf, lengthof(buf), _SC("Error %s:%d/%d: %s"), source, line, column, desc);
    00029 #endif
    00030
    00031   /* Check if we have a custom print function */
    00032   Squirrel *engine = (Squirrel *)sq_getforeignptr(vm);
    00033   engine->crashed = true;
    00034   SQPrintFunc *func = engine->print_func;
    00035   if (func == NULL) {
    00036     scfprintf(stderr, _SC("%s"), buf);
    00037   } else {
    00038     (*func)(true, buf);
    00039   }
    00040 }
    00041
    00042 void Squirrel::ErrorPrintFunc(HSQUIRRELVM vm, const SQChar *s, ...)
    00043 {
    00044   va_list arglist;
    00045   SQChar buf[1024];
    00046
    00047   va_start(arglist, s);
    00048   scvsnprintf(buf, lengthof(buf), s, arglist);
    00049   va_end(arglist);
    00050
    00051   /* Check if we have a custom print function */
    00052   SQPrintFunc *func = ((Squirrel *)sq_getforeignptr(vm))->print_func;
    00053   if (func == NULL) {
    00054     scfprintf(stderr, _SC("%s"), buf);
    00055   } else {
    00056     (*func)(true, buf);
    00057   }
    00058 }
    00059
    00060 void Squirrel::RunError(HSQUIRRELVM vm, const SQChar *error)
    00061 {
    00062   /* Set the print function to something that prints to stderr */
    00063   SQPRINTFUNCTION pf = sq_getprintfunc(vm);
    00064   sq_setprintfunc(vm, &Squirrel::ErrorPrintFunc);
    00065
    00066   /* Check if we have a custom print function */
    00067   SQChar buf[1024];
    00068   scsnprintf(buf, lengthof(buf), _SC("Your script made an error: %s\n"), error);
    00069   Squirrel *engine = (Squirrel *)sq_getforeignptr(vm);
    00070   SQPrintFunc *func = engine->print_func;
    00071   if (func == NULL) {
    00072     scfprintf(stderr, _SC("%s"), buf);
    00073   } else {
    00074     (*func)(true, buf);
    00075   }
    00076
    00077   /* Print below the error the stack, so the users knows what is happening */
    00078   sqstd_printcallstack(vm);
    00079   /* Reset the old print function */
    00080   sq_setprintfunc(vm, pf);
    00081 }
    00082
    00083 SQInteger Squirrel::_RunError(HSQUIRRELVM vm)
    00084 {
    00085   const SQChar *sErr = 0;
    00086
    00087   if (sq_gettop(vm) >= 1) {
    00088     if (SQ_SUCCEEDED(sq_getstring(vm, -1, &sErr))) {
    00089       Squirrel::RunError(vm, sErr);
    00090       return 0;
    00091     }
    00092   }
    00093
    00094   Squirrel::RunError(vm, _SC("unknown error"));
    00095   return 0;
    00096 }
    00097
    00098 void Squirrel::PrintFunc(HSQUIRRELVM vm, const SQChar *s, ...)
    00099 {
    00100   va_list arglist;
    00101   SQChar buf[1024];
    00102
    00103   va_start(arglist, s);
    00104   scvsnprintf(buf, lengthof(buf) - 2, s, arglist);
    00105   va_end(arglist);
    00106   scstrcat(buf, _SC("\n"));
    00107
    00108   /* Check if we have a custom print function */
    00109   SQPrintFunc *func = ((Squirrel *)sq_getforeignptr(vm))->print_func;
    00110   if (func == NULL) {
    00111     scprintf(_SC("%s"), buf);
    00112   } else {
    00113     (*func)(false, buf);
    00114   }
    00115 }
    00116
    00117 void Squirrel::AddMethod(const char *method_name, SQFUNCTION proc, uint nparam, const char *params, void *userdata, int size)
    00118 {
    00119   sq_pushstring(this->vm, OTTD2SQ(method_name), -1);
    00120
    00121   if (size != 0) {
    00122     void *ptr = sq_newuserdata(vm, size);
    00123     memcpy(ptr, userdata, size);
    00124   }
    00125
    00126   sq_newclosure(this->vm, proc, size != 0 ? 1 : 0);
    00127   if (nparam != 0) sq_setparamscheck(this->vm, nparam, OTTD2SQ(params));
    00128   sq_setnativeclosurename(this->vm, -1, OTTD2SQ(method_name));
    00129   sq_newslot(this->vm, -3, SQFalse);
    00130 }
    00131
    00132 void Squirrel::AddConst(const char *var_name, int value)
    00133 {
    00134   sq_pushstring(this->vm, OTTD2SQ(var_name), -1);
    00135   sq_pushinteger(this->vm, value);
    00136   sq_newslot(this->vm, -3, SQTrue);
    00137 }
    00138
    00139 void Squirrel::AddConst(const char *var_name, bool value)
    00140 {
    00141   sq_pushstring(this->vm, OTTD2SQ(var_name), -1);
    00142   sq_pushbool(this->vm, value);
    00143   sq_newslot(this->vm, -3, SQTrue);
    00144 }
    00145
    00146 void Squirrel::AddClassBegin(const char *class_name)
    00147 {
    00148   sq_pushroottable(this->vm);
    00149   sq_pushstring(this->vm, OTTD2SQ(class_name), -1);
    00150   sq_newclass(this->vm, SQFalse);
    00151 }
    00152
    00153 void Squirrel::AddClassBegin(const char *class_name, const char *parent_class)
    00154 {
    00155   sq_pushroottable(this->vm);
    00156   sq_pushstring(this->vm, OTTD2SQ(class_name), -1);
    00157   sq_pushstring(this->vm, OTTD2SQ(parent_class), -1);
    00158   if (SQ_FAILED(sq_get(this->vm, -3))) {
    00159     DEBUG(misc, 0, "[squirrel] Failed to initialize class '%s' based on parent class '%s'", class_name, parent_class);
    00160     DEBUG(misc, 0, "[squirrel] Make sure that '%s' exists before trying to define '%s'", parent_class, class_name);
    00161     return;
    00162   }
    00163   sq_newclass(this->vm, SQTrue);
    00164 }
    00165
    00166 void Squirrel::AddClassEnd()
    00167 {
    00168   sq_newslot(vm, -3, SQFalse);
    00169   sq_pop(vm, 1);
    00170 }
    00171
    00172 bool Squirrel::MethodExists(HSQOBJECT instance, const char *method_name)
    00173 {
    00174   assert(!this->crashed);
    00175   int top = sq_gettop(this->vm);
    00176   /* Go to the instance-root */
    00177   sq_pushobject(this->vm, instance);
    00178   /* Find the function-name inside the script */
    00179   sq_pushstring(this->vm, OTTD2SQ(method_name), -1);
    00180   if (SQ_FAILED(sq_get(this->vm, -2))) {
    00181     sq_settop(this->vm, top);
    00182     return false;
    00183   }
    00184   sq_settop(this->vm, top);
    00185   return true;
    00186 }
    00187
    00188 bool Squirrel::Resume(int suspend)
    00189 {
    00190   assert(!this->crashed);
    00191   /* Did we use more operations than we should have in the
    00192    * previous tick? If so, subtract that from the current run. */
    00193   if (this->overdrawn_ops > 0 && suspend > 0) {
    00194     this->overdrawn_ops -= suspend;
    00195     /* Do we need to wait even more? */
    00196     if (this->overdrawn_ops >= 0) return true;
    00197
    00198     /* We can now only run whatever is "left". */
    00199     suspend = -this->overdrawn_ops;
    00200   }
    00201
    00202   this->crashed = !sq_resumecatch(this->vm, suspend);
    00203   this->overdrawn_ops = -this->vm->_ops_till_suspend;
    00204   return this->vm->_suspended != 0;
    00205 }
    00206
    00207 void Squirrel::ResumeError()
    00208 {
    00209   assert(!this->crashed);
    00210   sq_resumeerror(this->vm);
    00211 }
    00212
    00213 void Squirrel::CollectGarbage()
    00214 {
    00215   sq_collectgarbage(this->vm);
    00216 }
    00217
    00218 bool Squirrel::CallMethod(HSQOBJECT instance, const char *method_name, HSQOBJECT *ret, int suspend)
    00219 {
    00220   assert(!this->crashed);
    00221   /* Store the stack-location for the return value. We need to
    00222    * restore this after saving or the stack will be corrupted
    00223    * if we're in the middle of a DoCommand. */
    00224   SQInteger last_target = this->vm->_suspended_target;
    00225   /* Store the current top */
    00226   int top = sq_gettop(this->vm);
    00227   /* Go to the instance-root */
    00228   sq_pushobject(this->vm, instance);
    00229   /* Find the function-name inside the script */
    00230   sq_pushstring(this->vm, OTTD2SQ(method_name), -1);
    00231   if (SQ_FAILED(sq_get(this->vm, -2))) {
    00232     DEBUG(misc, 0, "[squirrel] Could not find '%s' in the class", method_name);
    00233     sq_settop(this->vm, top);
    00234     return false;
    00235   }
    00236   /* Call the method */
    00237   sq_pushobject(this->vm, instance);
    00238   if (SQ_FAILED(sq_call(this->vm, 1, ret == NULL ? SQFalse : SQTrue, SQTrue, suspend))) return false;
    00239   if (ret != NULL) sq_getstackobj(vm, -1, ret);
    00240   /* Reset the top, but don't do so for the AI main function, as we need
    00241    *  a correct stack when resuming. */
    00242   if (suspend == -1 || !this->IsSuspended()) sq_settop(this->vm, top);
    00243   /* Restore the return-value location. */
    00244   this->vm->_suspended_target = last_target;
    00245
    00246   return true;
    00247 }
    00248
    00249 bool Squirrel::CallStringMethodStrdup(HSQOBJECT instance, const char *method_name, const char **res, int suspend)
    00250 {
    00251   HSQOBJECT ret;
    00252   if (!this->CallMethod(instance, method_name, &ret, suspend)) return false;
    00253   if (ret._type != OT_STRING) return false;
    00254   *res = strdup(ObjectToString(&ret));
    00255   return true;
    00256 }
    00257
    00258 bool Squirrel::CallIntegerMethod(HSQOBJECT instance, const char *method_name, int *res, int suspend)
    00259 {
    00260   HSQOBJECT ret;
    00261   if (!this->CallMethod(instance, method_name, &ret, suspend)) return false;
    00262   if (ret._type != OT_INTEGER) return false;
    00263   *res = ObjectToInteger(&ret);
    00264   return true;
    00265 }
    00266
    00267 bool Squirrel::CallBoolMethod(HSQOBJECT instance, const char *method_name, bool *res, int suspend)
    00268 {
    00269   HSQOBJECT ret;
    00270   if (!this->CallMethod(instance, method_name, &ret, suspend)) return false;
    00271   if (ret._type != OT_BOOL) return false;
    00272   *res = ObjectToBool(&ret);
    00273   return true;
    00274 }
    00275
    00276 /* static */ bool Squirrel::CreateClassInstanceVM(HSQUIRRELVM vm, const char *class_name, void *real_instance, HSQOBJECT *instance, SQRELEASEHOOK release_hook)
    00277 {
    00278   int oldtop = sq_gettop(vm);
    00279
    00280   /* First, find the class */
    00281   sq_pushroottable(vm);
    00282   sq_pushstring(vm, OTTD2SQ(class_name), -1);
    00283   if (SQ_FAILED(sq_get(vm, -2))) {
    00284     DEBUG(misc, 0, "[squirrel] Failed to find class by the name '%s'", class_name);
    00285     sq_settop(vm, oldtop);
    00286     return false;
    00287   }
    00288
    00289   /* Create the instance */
    00290   if (SQ_FAILED(sq_createinstance(vm, -1))) {
    00291     DEBUG(misc, 0, "[squirrel] Failed to create instance for class '%s'", class_name);
    00292     sq_settop(vm, oldtop);
    00293     return false;
    00294   }
    00295
    00296   if (instance != NULL) {
    00297     /* Find our instance */
    00298     sq_getstackobj(vm, -1, instance);
    00299     /* Add a reference to it, so it survives for ever */
    00300     sq_addref(vm, instance);
    00301   }
    00302   sq_remove(vm, -2); // Class-name
    00303   sq_remove(vm, -2); // Root-table
    00304
    00305   /* Store it in the class */
    00306   sq_setinstanceup(vm, -1, real_instance);
    00307   if (release_hook != NULL) sq_setreleasehook(vm, -1, release_hook);
    00308
    00309   if (instance != NULL) sq_settop(vm, oldtop);
    00310
    00311   return true;
    00312 }
    00313
    00314 bool Squirrel::CreateClassInstance(const char *class_name, void *real_instance, HSQOBJECT *instance)
    00315 {
    00316   return Squirrel::CreateClassInstanceVM(this->vm, class_name, real_instance, instance, NULL);
    00317 }
    00318
    00319 Squirrel::Squirrel()
    00320 {
    00321   this->vm = sq_open(1024);
    00322   this->print_func = NULL;
    00323   this->global_pointer = NULL;
    00324   this->crashed = false;
    00325   this->overdrawn_ops = 0;
    00326
    00327   /* Handle compile-errors ourself, so we can display it nicely */
    00328   sq_setcompilererrorhandler(this->vm, &Squirrel::CompileError);
    00329   sq_notifyallexceptions(this->vm, SQTrue);
    00330   /* Set a good print-function */
    00331   sq_setprintfunc(this->vm, &Squirrel::PrintFunc);
    00332   /* Handle runtime-errors ourself, so we can display it nicely */
    00333   sq_newclosure(this->vm, &Squirrel::_RunError, 0);
    00334   sq_seterrorhandler(this->vm);
    00335
    00336   /* Set the foreigh pointer, so we can always find this instance from within the VM */
    00337   sq_setforeignptr(this->vm, this);
    00338
    00339   sq_pushroottable(this->vm);
    00340   squirrel_register_global_std(this);
    00341 }
    00342
    00343 class SQFile {
    00344 private:
    00345   FILE *file;
    00346   size_t size;
    00347   size_t pos;
    00348
    00349 public:
    00350   SQFile(FILE *file, size_t size) : file(file), size(size), pos(0) {}
    00351
    00352   size_t Read(void *buf, size_t elemsize, size_t count)
    00353   {
    00354     assert(elemsize != 0);
    00355     if (this->pos + (elemsize * count) > this->size) {
    00356       count = (this->size - this->pos) / elemsize;
    00357     }
    00358     if (count == 0) return 0;
    00359     size_t ret = fread(buf, elemsize, count, this->file);
    00360     this->pos += ret * elemsize;
    00361     return ret;
    00362   }
    00363 };
    00364
    00365 static SQInteger _io_file_lexfeed_ASCII(SQUserPointer file)
    00366 {
    00367   char c;
    00368   if (((SQFile *)file)->Read(&c, sizeof(c), 1) > 0) return c;
    00369   return 0;
    00370 }
    00371
    00372 static SQInteger _io_file_lexfeed_UTF8(SQUserPointer file)
    00373 {
    00374   static const SQInteger utf8_lengths[16] =
    00375   {
    00376     1, 1, 1, 1, 1, 1, 1, 1, /* 0000 to 0111 : 1 byte (plain ASCII) */
    00377     0, 0, 0, 0,             /* 1000 to 1011 : not valid */
    00378     2, 2,                   /* 1100, 1101 : 2 bytes */
    00379     3,                      /* 1110 : 3 bytes */
    00380     4                       /* 1111 : 4 bytes */
    00381   };
    00382   static unsigned char byte_masks[5] = {0, 0, 0x1F, 0x0F, 0x07};
    00383   unsigned char inchar;
    00384   SQInteger c = 0;
    00385   if (((SQFile *)file)->Read(&inchar, sizeof(inchar), 1) != 1) return 0;
    00386   c = inchar;
    00387
    00388   if (c >= 0x80) {
    00389     SQInteger tmp;
    00390     SQInteger codelen = utf8_lengths[c >> 4];
    00391     if (codelen == 0) return 0;
    00392
    00393     tmp = c & byte_masks[codelen];
    00394     for (SQInteger n = 0; n < codelen - 1; n++) {
    00395       tmp <<= 6;
    00396       if (((SQFile *)file)->Read(&inchar, sizeof(inchar), 1) != 1) return 0;
    00397       tmp |= inchar & 0x3F;
    00398     }
    00399     c = tmp;
    00400   }
    00401   return c;
    00402 }
    00403
    00404 static SQInteger _io_file_lexfeed_UCS2_LE(SQUserPointer file)
    00405 {
    00406   wchar_t c;
    00407   if (((SQFile *)file)->Read(&c, sizeof(c), 1) > 0) return (SQChar)c;
    00408   return 0;
    00409 }
    00410
    00411 static SQInteger _io_file_lexfeed_UCS2_BE(SQUserPointer file)
    00412 {
    00413   unsigned short c;
    00414   if (((SQFile *)file)->Read(&c, sizeof(c), 1) > 0) {
    00415     c = ((c >> 8) & 0x00FF)| ((c << 8) & 0xFF00);
    00416     return (SQChar)c;
    00417   }
    00418   return 0;
    00419 }
    00420
    00421 static SQInteger _io_file_read(SQUserPointer file, SQUserPointer buf, SQInteger size)
    00422 {
    00423   SQInteger ret = ((SQFile *)file)->Read(buf, 1, size);
    00424   if (ret == 0) return -1;
    00425   return ret;
    00426 }
    00427
    00428 /* static */ SQRESULT Squirrel::LoadFile(HSQUIRRELVM vm, const char *filename, SQBool printerror)
    00429 {
    00430   size_t size;
    00431   FILE *file = FioFOpenFile(filename, "rb", AI_DIR, &size);
    00432   SQInteger ret;
    00433   unsigned short us;
    00434   unsigned char uc;
    00435   SQLEXREADFUNC func;
    00436
    00437   if (file != NULL) {
    00438     SQFile f(file, size);
    00439     ret = fread(&us, 1, sizeof(us), file);
    00440     /* Most likely an empty file */
    00441     if (ret != 2) us = 0;
    00442
    00443     switch (us) {
    00444       case SQ_BYTECODE_STREAM_TAG: { // BYTECODE
    00445         fseek(file, -2, SEEK_CUR);
    00446         if (SQ_SUCCEEDED(sq_readclosure(vm, _io_file_read, &f))) {
    00447           FioFCloseFile(file);
    00448           return SQ_OK;
    00449         }
    00450         FioFCloseFile(file);
    00451         return sq_throwerror(vm, _SC("Couldn't read bytecode"));
    00452       }
    00453       case 0xFFFE: func = _io_file_lexfeed_UCS2_BE; break; // UTF-16 little endian
    00454       case 0xFEFF: func = _io_file_lexfeed_UCS2_LE; break; // UTF-16 big endian
    00455       case 0xBBEF: // UTF-8
    00456         if (fread(&uc, 1, sizeof(uc), file) == 0) {
    00457           FioFCloseFile(file);
    00458           return sq_throwerror(vm, _SC("I/O error"));
    00459         }
    00460         if (uc != 0xBF) {
    00461           FioFCloseFile(file);
    00462           return sq_throwerror(vm, _SC("Unrecognized encoding"));
    00463         }
    00464         func = _io_file_lexfeed_UTF8;
    00465         break;
    00466       default: func = _io_file_lexfeed_ASCII; fseek(file, -2, SEEK_CUR); break; // ASCII
    00467     }
    00468
    00469     if (SQ_SUCCEEDED(sq_compile(vm, func, &f, OTTD2SQ(filename), printerror))) {
    00470       FioFCloseFile(file);
    00471       return SQ_OK;
    00472     }
    00473     FioFCloseFile(file);
    00474     return SQ_ERROR;
    00475   }
    00476   return sq_throwerror(vm, _SC("cannot open the file"));
    00477 }
    00478
    00479 /* static */ bool Squirrel::LoadScript(HSQUIRRELVM vm, const char *script, bool in_root)
    00480 {
    00481   /* Make sure we are always in the root-table */
    00482   if (in_root) sq_pushroottable(vm);
    00483
    00484   /* Load and run the script */
    00485   if (SQ_SUCCEEDED(LoadFile(vm, script, SQTrue))) {
    00486     sq_push(vm, -2);
    00487     if (SQ_SUCCEEDED(sq_call(vm, 1, SQFalse, SQTrue, 100000))) {
    00488       sq_pop(vm, 1);
    00489       return true;
    00490     }
    00491   }
    00492
    00493   DEBUG(misc, 0, "[squirrel] Failed to compile '%s'", script);
    00494   return false;
    00495 }
    00496
    00497 bool Squirrel::LoadScript(const char *script)
    00498 {
    00499   return LoadScript(this->vm, script);
    00500 }
    00501
    00502 Squirrel::~Squirrel()
    00503 {
    00504   /* Clean up the stuff */
    00505   sq_pop(this->vm, 1);
    00506   sq_close(this->vm);
    00507 }
    00508
    00509 void Squirrel::InsertResult(bool result)
    00510 {
    00511   sq_pushbool(this->vm, result);
    00512   vm->GetAt(vm->_stackbase + vm->_suspended_target) = vm->GetUp(-1);
    00513   vm->Pop();
    00514 }
    00515
    00516 void Squirrel::InsertResult(int result)
    00517 {
    00518   sq_pushinteger(this->vm, result);
    00519   vm->GetAt(vm->_stackbase + vm->_suspended_target) = vm->GetUp(-1);
    00520   vm->Pop();
    00521 }
    00522
    00523 /* static */ void Squirrel::DecreaseOps(HSQUIRRELVM vm, int ops)
    00524 {
    00525   vm->DecreaseOps(ops);
    00526 }
    00527
    00528 bool Squirrel::IsSuspended()
    00529 {
    00530   return this->vm->_suspended != 0;
    00531 }
    00532
    00533 bool Squirrel::HasScriptCrashed()
    00534 {
    00535   return this->crashed;
    00536 }
    00537
    00538 void Squirrel::ResetCrashed()
    00539 {
    00540   this->crashed = false;
    00541 }
    00542
    00543 void Squirrel::CrashOccurred()
    00544 {
    00545   this->crashed = true;
    00546 }
    00547
    00548 bool Squirrel::CanSuspend()
    00549 {
    00550   return sq_can_suspend(this->vm);
    00551 }