ANSI C library interface

Path: /sdk/add_on/clib/

This add-on defines a pure C interface, that can be used in those applications that do not understand C++ code but do understand C, e.g. Delphi, Java, and D.

To compile the AngelScript C library, you need to compile the library source files in sdk/angelscript/source together with the source files in sdk/add-on/clib, and link them as a shared dynamic library. In the application that will use the AngelScript C library, you'll include the angelscript_c.h header file, instead of the ordinary angelscript.h header file. After that you can use the library much the same way that it's used in C++.

To find the name of the C functions to call, you normally take the corresponding interface method and give a prefix according to the following table:

interface	prefix
asIScriptEngine	asEngine_
asIScriptModule	asModule_
asIScriptContext	asContext_
asIScriptGeneric	asGeneric_
asIScriptObject	asObject_
asIObjectType	asObjectType_
asIScriptFunction	asFunction_

All interface methods take the interface pointer as the first parameter when in the C function format, the rest of the parameters are the same as in the C++ interface. There are a few exceptions though, e.g. all parameters that take an asSFuncPtr take a normal function pointer in the C function format.

Example:

#include <stdio.h>
#include <assert.h>
#include "angelscript_c.h"

void MessageCallback(asSMessageInfo *msg, void *);
void PrintSomething();

int main(int argc, char **argv)
{
  int r = 0;

  // Create and initialize the script engine
  asIScriptEngine *engine = asCreateScriptEngine(ANGELSCRIPT_VERSION);
  r = asEngine_SetMessageCallback(engine, (asFUNCTION_t)MessageCallback, 0, asCALL_CDECL); assert( r >= 0 );
  r = asEngine_RegisterGlobalFunction(engine, "void print()", (asFUNCTION_t)PrintSomething, asCALL_CDECL); assert( r >= 0 );

  // Execute a simple script
  r = asEngine_ExecuteString(engine, 0, "print()", 0, 0);
  if( r != asEXECUTION_FINISHED )
  {
      printf("Something wen't wrong with the execution\n");
  }
  else
  {
      printf("The script was executed successfully\n");
  }

  // Release the script engine
  asEngine_Release(engine);
  
  return r;
}

void MessageCallback(asSMessageInfo *msg, void *)
{
  const char *msgType = 0;
  if( msg->type == 0 ) msgType = "Error  ";
  if( msg->type == 1 ) msgType = "Warning";
  if( msg->type == 2 ) msgType = "Info   ";

  printf("%s (%d, %d) : %s : %s\n", msg->section, msg->row, msg->col, msgType, msg->message);
}

void PrintSomething()
{
  printf("Called from the script\n");
}