# squirrel.cpp

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    00001 /* $Id: squirrel.cpp 18038 2009-11-11 18:13:17Z rubidium $ */
    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 <squirrel.h>
    00013 #include <stdarg.h>
    00014 #include "../stdafx.h"
    00015 #include "../debug.h"
    00016 #include "squirrel.hpp"
    00017 #include "squirrel_std.hpp"
    00018 #include "../fileio_func.h"
    00019 #include <sqstdaux.h>
    00020 #include <../squirrel/sqpcheader.h>
    00021 #include <../squirrel/sqvm.h>
    00022
    00023 void Squirrel::CompileError(HSQUIRRELVM vm, const SQChar *desc, const SQChar *source, SQInteger line, SQInteger column)
    00024 {
    00025   SQChar buf[1024];
    00026
    00027 #ifdef _SQ64
    00028   scsnprintf(buf, lengthof(buf), _SC("Error %s:%ld/%ld: %s"), source, line, column, desc);
    00029 #else
    00030   scsnprintf(buf, lengthof(buf), _SC("Error %s:%d/%d: %s"), source, line, column, desc);
    00031 #endif
    00032
    00033   /* Check if we have a custom print function */
    00034   Squirrel *engine = (Squirrel *)sq_getforeignptr(vm);
    00035   engine->crashed = true;
    00036   SQPrintFunc *func = engine->print_func;
    00037   if (func == NULL) {
    00038     scfprintf(stderr, _SC("%s"), buf);
    00039   } else {
    00040     (*func)(true, buf);
    00041   }
    00042 }
    00043
    00044 void Squirrel::ErrorPrintFunc(HSQUIRRELVM vm, const SQChar *s, ...)
    00045 {
    00046   va_list arglist;
    00047   SQChar buf[1024];
    00048
    00049   va_start(arglist, s);
    00050   scvsnprintf(buf, lengthof(buf), s, arglist);
    00051   va_end(arglist);
    00052
    00053   /* Check if we have a custom print function */
    00054   SQPrintFunc *func = ((Squirrel *)sq_getforeignptr(vm))->print_func;
    00055   if (func == NULL) {
    00056     scfprintf(stderr, _SC("%s"), buf);
    00057   } else {
    00058     (*func)(true, buf);
    00059   }
    00060 }
    00061
    00062 void Squirrel::RunError(HSQUIRRELVM vm, const SQChar *error)
    00063 {
    00064   /* Set the print function to something that prints to stderr */
    00065   SQPRINTFUNCTION pf = sq_getprintfunc(vm);
    00066   sq_setprintfunc(vm, &Squirrel::ErrorPrintFunc);
    00067
    00068   /* Check if we have a custom print function */
    00069   SQChar buf[1024];
    00070   scsnprintf(buf, lengthof(buf), _SC("Your script made an error: %s\n"), error);
    00071   Squirrel *engine = (Squirrel *)sq_getforeignptr(vm);
    00072   SQPrintFunc *func = engine->print_func;
    00073   if (func == NULL) {
    00074     scfprintf(stderr, _SC("%s"), buf);
    00075   } else {
    00076     (*func)(true, buf);
    00077   }
    00078
    00079   /* Print below the error the stack, so the users knows what is happening */
    00080   sqstd_printcallstack(vm);
    00081   /* Reset the old print function */
    00082   sq_setprintfunc(vm, pf);
    00083 }
    00084
    00085 SQInteger Squirrel::_RunError(HSQUIRRELVM vm)
    00086 {
    00087   const SQChar *sErr = 0;
    00088
    00089   if (sq_gettop(vm) >= 1) {
    00090     if (SQ_SUCCEEDED(sq_getstring(vm, -1, &sErr))) {
    00091       Squirrel::RunError(vm, sErr);
    00092       return 0;
    00093     }
    00094   }
    00095
    00096   Squirrel::RunError(vm, _SC("unknown error"));
    00097   return 0;
    00098 }
    00099
    00100 void Squirrel::PrintFunc(HSQUIRRELVM vm, const SQChar *s, ...)
    00101 {
    00102   va_list arglist;
    00103   SQChar buf[1024];
    00104
    00105   va_start(arglist, s);
    00106   scvsnprintf(buf, lengthof(buf) - 2, s, arglist);
    00107   va_end(arglist);
    00108   scstrcat(buf, _SC("\n"));
    00109
    00110   /* Check if we have a custom print function */
    00111   SQPrintFunc *func = ((Squirrel *)sq_getforeignptr(vm))->print_func;
    00112   if (func == NULL) {
    00113     scprintf(_SC("%s"), buf);
    00114   } else {
    00115     (*func)(false, buf);
    00116   }
    00117 }
    00118
    00119 void Squirrel::AddMethod(const char *method_name, SQFUNCTION proc, uint nparam, const char *params, void *userdata, int size)
    00120 {
    00121   sq_pushstring(this->vm, OTTD2FS(method_name), -1);
    00122
    00123   if (size != 0) {
    00124     void *ptr = sq_newuserdata(vm, size);
    00125     memcpy(ptr, userdata, size);
    00126   }
    00127
    00128   sq_newclosure(this->vm, proc, size != 0 ? 1 : 0);
    00129   if (nparam != 0) sq_setparamscheck(this->vm, nparam, OTTD2FS(params));
    00130   sq_setnativeclosurename(this->vm, -1, OTTD2FS(method_name));
    00131   sq_newslot(this->vm, -3, SQFalse);
    00132 }
    00133
    00134 void Squirrel::AddConst(const char *var_name, int value)
    00135 {
    00136   sq_pushstring(this->vm, OTTD2FS(var_name), -1);
    00137   sq_pushinteger(this->vm, value);
    00138   sq_newslot(this->vm, -3, SQTrue);
    00139 }
    00140
    00141 void Squirrel::AddConst(const char *var_name, bool value)
    00142 {
    00143   sq_pushstring(this->vm, OTTD2FS(var_name), -1);
    00144   sq_pushbool(this->vm, value);
    00145   sq_newslot(this->vm, -3, SQTrue);
    00146 }
    00147
    00148 void Squirrel::AddClassBegin(const char *class_name)
    00149 {
    00150   sq_pushroottable(this->vm);
    00151   sq_pushstring(this->vm, OTTD2FS(class_name), -1);
    00152   sq_newclass(this->vm, SQFalse);
    00153 }
    00154
    00155 void Squirrel::AddClassBegin(const char *class_name, const char *parent_class)
    00156 {
    00157   sq_pushroottable(this->vm);
    00158   sq_pushstring(this->vm, OTTD2FS(class_name), -1);
    00159   sq_pushstring(this->vm, OTTD2FS(parent_class), -1);
    00160   if (SQ_FAILED(sq_get(this->vm, -3))) {
    00161     DEBUG(misc, 0, "[squirrel] Failed to initialize class '%s' based on parent class '%s'", class_name, parent_class);
    00162     DEBUG(misc, 0, "[squirrel] Make sure that '%s' exists before trying to define '%s'", parent_class, class_name);
    00163     return;
    00164   }
    00165   sq_newclass(this->vm, SQTrue);
    00166 }
    00167
    00168 void Squirrel::AddClassEnd()
    00169 {
    00170   sq_newslot(vm, -3, SQFalse);
    00171   sq_pop(vm, 1);
    00172 }
    00173
    00174 bool Squirrel::MethodExists(HSQOBJECT instance, const char *method_name)
    00175 {
    00176   assert(!this->crashed);
    00177   int top = sq_gettop(this->vm);
    00178   /* Go to the instance-root */
    00179   sq_pushobject(this->vm, instance);
    00180   /* Find the function-name inside the script */
    00181   sq_pushstring(this->vm, OTTD2FS(method_name), -1);
    00182   if (SQ_FAILED(sq_get(this->vm, -2))) {
    00183     sq_settop(this->vm, top);
    00184     return false;
    00185   }
    00186   sq_settop(this->vm, top);
    00187   return true;
    00188 }
    00189
    00190 bool Squirrel::Resume(int suspend)
    00191 {
    00192   assert(!this->crashed);
    00193   this->crashed = !sq_resumecatch(this->vm, suspend);
    00194   return this->vm->_suspended != 0;
    00195 }
    00196
    00197 void Squirrel::ResumeError()
    00198 {
    00199   assert(!this->crashed);
    00200   sq_resumeerror(this->vm);
    00201 }
    00202
    00203 void Squirrel::CollectGarbage()
    00204 {
    00205   sq_collectgarbage(this->vm);
    00206 }
    00207
    00208 bool Squirrel::CallMethod(HSQOBJECT instance, const char *method_name, HSQOBJECT *ret, int suspend)
    00209 {
    00210   assert(!this->crashed);
    00211   /* Store the stack-location for the return value. We need to
    00212    * restore this after saving or the stack will be corrupted
    00213    * if we're in the middle of a DoCommand. */
    00214   SQInteger last_target = this->vm->_suspended_target;
    00215   /* Store the current top */
    00216   int top = sq_gettop(this->vm);
    00217   /* Go to the instance-root */
    00218   sq_pushobject(this->vm, instance);
    00219   /* Find the function-name inside the script */
    00220   sq_pushstring(this->vm, OTTD2FS(method_name), -1);
    00221   if (SQ_FAILED(sq_get(this->vm, -2))) {
    00222     DEBUG(misc, 0, "[squirrel] Could not find '%s' in the class", method_name);
    00223     sq_settop(this->vm, top);
    00224     return false;
    00225   }
    00226   /* Call the method */
    00227   sq_pushobject(this->vm, instance);
    00228   if (SQ_FAILED(sq_call(this->vm, 1, ret == NULL ? SQFalse : SQTrue, SQTrue, suspend))) return false;
    00229   if (ret != NULL) sq_getstackobj(vm, -1, ret);
    00230   /* Reset the top, but don't do so for the AI main function, as we need
    00231    *  a correct stack when resuming. */
    00232   if (suspend == -1 || !this->IsSuspended()) sq_settop(this->vm, top);
    00233   /* Restore the return-value location. */
    00234   this->vm->_suspended_target = last_target;
    00235
    00236   return true;
    00237 }
    00238
    00239 bool Squirrel::CallStringMethodStrdup(HSQOBJECT instance, const char *method_name, const char **res, int suspend)
    00240 {
    00241   HSQOBJECT ret;
    00242   if (!this->CallMethod(instance, method_name, &ret, suspend)) return false;
    00243   if (ret._type != OT_STRING) return false;
    00244   *res = strdup(ObjectToString(&ret));
    00245   return true;
    00246 }
    00247
    00248 bool Squirrel::CallIntegerMethod(HSQOBJECT instance, const char *method_name, int *res, int suspend)
    00249 {
    00250   HSQOBJECT ret;
    00251   if (!this->CallMethod(instance, method_name, &ret, suspend)) return false;
    00252   if (ret._type != OT_INTEGER) return false;
    00253   *res = ObjectToInteger(&ret);
    00254   return true;
    00255 }
    00256
    00257 bool Squirrel::CallBoolMethod(HSQOBJECT instance, const char *method_name, bool *res, int suspend)
    00258 {
    00259   HSQOBJECT ret;
    00260   if (!this->CallMethod(instance, method_name, &ret, suspend)) return false;
    00261   if (ret._type != OT_BOOL) return false;
    00262   *res = ObjectToBool(&ret);
    00263   return true;
    00264 }
    00265
    00266 /* static */ bool Squirrel::CreateClassInstanceVM(HSQUIRRELVM vm, const char *class_name, void *real_instance, HSQOBJECT *instance, SQRELEASEHOOK release_hook)
    00267 {
    00268   int oldtop = sq_gettop(vm);
    00269
    00270   /* First, find the class */
    00271   sq_pushroottable(vm);
    00272   sq_pushstring(vm, OTTD2FS(class_name), -1);
    00273   if (SQ_FAILED(sq_get(vm, -2))) {
    00274     DEBUG(misc, 0, "[squirrel] Failed to find class by the name '%s'", class_name);
    00275     sq_settop(vm, oldtop);
    00276     return false;
    00277   }
    00278
    00279   /* Create the instance */
    00280   if (SQ_FAILED(sq_createinstance(vm, -1))) {
    00281     DEBUG(misc, 0, "[squirrel] Failed to create instance for class '%s'", class_name);
    00282     sq_settop(vm, oldtop);
    00283     return false;
    00284   }
    00285
    00286   if (instance != NULL) {
    00287     /* Find our instance */
    00288     sq_getstackobj(vm, -1, instance);
    00289     /* Add a reference to it, so it survives for ever */
    00290     sq_addref(vm, instance);
    00291   }
    00292   sq_remove(vm, -2); // Class-name
    00293   sq_remove(vm, -2); // Root-table
    00294
    00295   /* Store it in the class */
    00296   sq_setinstanceup(vm, -1, real_instance);
    00297   if (release_hook != NULL) sq_setreleasehook(vm, -1, release_hook);
    00298
    00299   if (instance != NULL) sq_settop(vm, oldtop);
    00300
    00301   return true;
    00302 }
    00303
    00304 bool Squirrel::CreateClassInstance(const char *class_name, void *real_instance, HSQOBJECT *instance)
    00305 {
    00306   return Squirrel::CreateClassInstanceVM(this->vm, class_name, real_instance, instance, NULL);
    00307 }
    00308
    00309 Squirrel::Squirrel()
    00310 {
    00311   this->vm = sq_open(1024);
    00312   this->print_func = NULL;
    00313   this->global_pointer = NULL;
    00314   this->crashed = false;
    00315
    00316   /* Handle compile-errors ourself, so we can display it nicely */
    00317   sq_setcompilererrorhandler(this->vm, &Squirrel::CompileError);
    00318   sq_notifyallexceptions(this->vm, SQTrue);
    00319   /* Set a good print-function */
    00320   sq_setprintfunc(this->vm, &Squirrel::PrintFunc);
    00321   /* Handle runtime-errors ourself, so we can display it nicely */
    00322   sq_newclosure(this->vm, &Squirrel::_RunError, 0);
    00323   sq_seterrorhandler(this->vm);
    00324
    00325   /* Set the foreigh pointer, so we can always find this instance from within the VM */
    00326   sq_setforeignptr(this->vm, this);
    00327
    00328   sq_pushroottable(this->vm);
    00329   squirrel_register_global_std(this);
    00330 }
    00331
    00332 class SQFile {
    00333 private:
    00334   FILE *file;
    00335   size_t size;
    00336   size_t pos;
    00337
    00338 public:
    00339   SQFile(FILE *file, size_t size) : file(file), size(size), pos(0) {}
    00340
    00341   size_t Read(void *buf, size_t elemsize, size_t count)
    00342   {
    00343     assert(elemsize != 0);
    00344     if (this->pos + (elemsize * count) > this->size) {
    00345       count = (this->size - this->pos) / elemsize;
    00346     }
    00347     if (count == 0) return 0;
    00348     size_t ret = fread(buf, elemsize, count, this->file);
    00349     this->pos += ret * elemsize;
    00350     return ret;
    00351   }
    00352 };
    00353
    00354 static SQInteger _io_file_lexfeed_ASCII(SQUserPointer file)
    00355 {
    00356   char c;
    00357   if (((SQFile *)file)->Read(&c, sizeof(c), 1) > 0) return c;
    00358   return 0;
    00359 }
    00360
    00361 static SQInteger _io_file_lexfeed_UTF8(SQUserPointer file)
    00362 {
    00363   static const SQInteger utf8_lengths[16] =
    00364   {
    00365     1, 1, 1, 1, 1, 1, 1, 1, /* 0000 to 0111 : 1 byte (plain ASCII) */
    00366     0, 0, 0, 0,             /* 1000 to 1011 : not valid */
    00367     2, 2,                   /* 1100, 1101 : 2 bytes */
    00368     3,                      /* 1110 : 3 bytes */
    00369     4                       /* 1111 : 4 bytes */
    00370   };
    00371   static unsigned char byte_masks[5] = {0, 0, 0x1F, 0x0F, 0x07};
    00372   unsigned char inchar;
    00373   SQInteger c = 0;
    00374   if (((SQFile *)file)->Read(&inchar, sizeof(inchar), 1) != 1) return 0;
    00375   c = inchar;
    00376
    00377   if (c >= 0x80) {
    00378     SQInteger tmp;
    00379     SQInteger codelen = utf8_lengths[c >> 4];
    00380     if (codelen == 0) return 0;
    00381
    00382     tmp = c & byte_masks[codelen];
    00383     for (SQInteger n = 0; n < codelen - 1; n++) {
    00384       tmp <<= 6;
    00385       if (((SQFile *)file)->Read(&inchar, sizeof(inchar), 1) != 1) return 0;
    00386       tmp |= inchar & 0x3F;
    00387     }
    00388     c = tmp;
    00389   }
    00390   return c;
    00391 }
    00392
    00393 static SQInteger _io_file_lexfeed_UCS2_LE(SQUserPointer file)
    00394 {
    00395   wchar_t c;
    00396   if (((SQFile *)file)->Read(&c, sizeof(c), 1) > 0) return (SQChar)c;
    00397   return 0;
    00398 }
    00399
    00400 static SQInteger _io_file_lexfeed_UCS2_BE(SQUserPointer file)
    00401 {
    00402   unsigned short c;
    00403   if (((SQFile *)file)->Read(&c, sizeof(c), 1) > 0) {
    00404     c = ((c >> 8) & 0x00FF)| ((c << 8) & 0xFF00);
    00405     return (SQChar)c;
    00406   }
    00407   return 0;
    00408 }
    00409
    00410 static SQInteger _io_file_read(SQUserPointer file, SQUserPointer buf, SQInteger size)
    00411 {
    00412   SQInteger ret = ((SQFile *)file)->Read(buf, 1, size);
    00413   if (ret == 0) return -1;
    00414   return ret;
    00415 }
    00416
    00417 /* static */ SQRESULT Squirrel::LoadFile(HSQUIRRELVM vm, const char *filename, SQBool printerror)
    00418 {
    00419   size_t size;
    00420   FILE *file = FioFOpenFile(filename, "rb", AI_DIR, &size);
    00421   SQInteger ret;
    00422   unsigned short us;
    00423   unsigned char uc;
    00424   SQLEXREADFUNC func;
    00425
    00426   if (file != NULL) {
    00427     SQFile f(file, size);
    00428     ret = fread(&us, 1, sizeof(us), file);
    00429     /* Most likely an empty file */
    00430     if (ret != 2) us = 0;
    00431
    00432     switch (us) {
    00433       case SQ_BYTECODE_STREAM_TAG: { // BYTECODE
    00434         fseek(file, -2, SEEK_CUR);
    00435         if (SQ_SUCCEEDED(sq_readclosure(vm, _io_file_read, &f))) {
    00436           FioFCloseFile(file);
    00437           return SQ_OK;
    00438         }
    00439         FioFCloseFile(file);
    00440         return sq_throwerror(vm, _SC("Couldn't read bytecode"));
    00441       }
    00442       case 0xFFFE: func = _io_file_lexfeed_UCS2_BE; break; // UTF-16 little endian
    00443       case 0xFEFF: func = _io_file_lexfeed_UCS2_LE; break; // UTF-16 big endian
    00444       case 0xBBEF: // UTF-8
    00445         if (fread(&uc, 1, sizeof(uc), file) == 0) {
    00446           FioFCloseFile(file);
    00447           return sq_throwerror(vm, _SC("I/O error"));
    00448         }
    00449         if (uc != 0xBF) {
    00450           FioFCloseFile(file);
    00451           return sq_throwerror(vm, _SC("Unrecognized encoding"));
    00452         }
    00453         func = _io_file_lexfeed_UTF8;
    00454         break;
    00455       default: func = _io_file_lexfeed_ASCII; fseek(file, -2, SEEK_CUR); break; // ASCII
    00456     }
    00457
    00458     if (SQ_SUCCEEDED(sq_compile(vm, func, &f, OTTD2FS(filename), printerror))) {
    00459       FioFCloseFile(file);
    00460       return SQ_OK;
    00461     }
    00462     FioFCloseFile(file);
    00463     return SQ_ERROR;
    00464   }
    00465   return sq_throwerror(vm, _SC("cannot open the file"));
    00466 }
    00467
    00468 /* static */ bool Squirrel::LoadScript(HSQUIRRELVM vm, const char *script, bool in_root)
    00469 {
    00470   /* Make sure we are always in the root-table */
    00471   if (in_root) sq_pushroottable(vm);
    00472
    00473   /* Load and run the script */
    00474   if (SQ_SUCCEEDED(LoadFile(vm, script, SQTrue))) {
    00475     sq_push(vm, -2);
    00476     if (SQ_SUCCEEDED(sq_call(vm, 1, SQFalse, SQTrue, 100000))) {
    00477       sq_pop(vm, 1);
    00478       return true;
    00479     }
    00480   }
    00481
    00482   DEBUG(misc, 0, "[squirrel] Failed to compile '%s'", script);
    00483   return false;
    00484 }
    00485
    00486 bool Squirrel::LoadScript(const char *script)
    00487 {
    00488   return LoadScript(this->vm, script);
    00489 }
    00490
    00491 Squirrel::~Squirrel()
    00492 {
    00493   /* Clean up the stuff */
    00494   sq_pop(this->vm, 1);
    00495   sq_close(this->vm);
    00496 }
    00497
    00498 void Squirrel::InsertResult(bool result)
    00499 {
    00500   sq_pushbool(this->vm, result);
    00501   vm->GetAt(vm->_stackbase + vm->_suspended_target) = vm->GetUp(-1);
    00502   vm->Pop();
    00503 }
    00504
    00505 void Squirrel::InsertResult(int result)
    00506 {
    00507   sq_pushinteger(this->vm, result);
    00508   vm->GetAt(vm->_stackbase + vm->_suspended_target) = vm->GetUp(-1);
    00509   vm->Pop();
    00510 }
    00511
    00512 /* static */ void Squirrel::DecreaseOps(HSQUIRRELVM vm, int ops)
    00513 {
    00514   vm->DecreaseOps(ops);
    00515 }
    00516
    00517 bool Squirrel::IsSuspended()
    00518 {
    00519   return this->vm->_suspended != 0;
    00520 }
    00521
    00522 bool Squirrel::HasScriptCrashed()
    00523 {
    00524   return this->crashed;
    00525 }
    00526
    00527 void Squirrel::ResetCrashed()
    00528 {
    00529   this->crashed = false;
    00530 }
    00531
    00532 void Squirrel::CrashOccurred()
    00533 {
    00534   this->crashed = true;
    00535 }
    00536
    00537 bool Squirrel::CanSuspend()
    00538 {
    00539   return sq_can_suspend(this->vm);
    00540 }