kolibrios/programs/fs/Eolite/trunk/lib/IPC.H--

//stuff for loading images via MeView via IPC by Nable. 2008
//Last changed 13.11.2008

inline fastcall void registerIPCbuffer(dword ECX, dword EDX)
//ecx - pointer to buffer, edx - buffer size
{
   EAX=60;
   EBX=1;
   $int 0x40
}

inline fastcall void build_param_string(dword ESI, dword EDI)
//first parameter - pointer to filename string, second - pointer to
//the output area for commandline for MeView
proc_info _p_info;
{
   _p_info.GetInfo(SelfInfo);
   EBX = _p_info.ID;
   EAX = 'NCPI';  //'IPCN' in reversed byte order
   $STOSD
   ECX = 8;

___NEW_SYMBOL_OF_PID:
   $ROL  EBX,4

   EAX =  EBX;
   EAX &= 0xF;
   EAX += '0';

   $CMP  AL,'9'
   $JBE  ___NEW_SYMBOL_OF_PID_PRINT
   $ADD  AL,7			    //('A'-'0'-10)
___NEW_SYMBOL_OF_PID_PRINT:
   $STOSB
   $LOOP ___NEW_SYMBOL_OF_PID

___NEW_SYMBOL_OF_PATH_COPY:
   $LODSB
   $STOSB
   $OR	 AL,AL
   $JNE  ___NEW_SYMBOL_OF_PATH_COPY
}

char _Path2MeView[]="/sys/mv";

inline int RunMV(char* parameters)
f70 _run_struct;
{
   _run_struct.func   = 7;
   _run_struct.param1 = 0;
   _run_struct.param2 = parameters;
   _run_struct.param3 = 
   _run_struct.param4 = 
   _run_struct.rezerv = 0;
   _run_struct.name   = #_Path2MeView;

   EAX=70;
   EBX=#_run_struct;
   $int 0x40
   //EAX (return code) will contain positive PID of new process or negative error code.
}


int loadimage_viaIPC(char* file_name_to_load, int initial_values)
//really it must be IMAGE_INFO* initial_values, but compiler rejected
//this, so I had to use 'int initial_values'
char param_string[255];
unsigned int _FrameCountTemp;
int temp0; //scratch variable
int came_size; //sizeof data that came. It's used to shrink unneeded IPC data
//added by Nable 13.11.2008 3.36am (begin)
int MVsPID; //no comments
int MVsSlot; //no comments
proc_info _p_info; //this structure will be used to test if MV is alive
//added by Nable 13.11.2008 3.36am (end)
{
   int pIPCbuffer = malloc(64); //IPC buffer for the first message can be
			    //rather small but >= 8+8+24

   /*Here you can add error checking code, i.e. if(!pIPCbuffer)
   { ErrorExit("OUT OF MEMORY!"); }; */

   registerIPCbuffer(pIPCbuffer,64);
   DSDWORD[pIPCbuffer+4]=8; //at +4 in IPC buffer is a relative pointer to free place

   build_param_string(file_name_to_load, #param_string);

   DSDWORD[pIPCbuffer]=0; //unlock the buffer

   SetEventMask(01000000b); // 1 << (evIPC-1)
//13.11.2008 3.45am Nable's fixes (begin1)
	MVsPID = RunMV(#param_string); //you can use here your function but don't forget
	//about parameters (param_string).
	MVsSlot = PIDtoSlot(MVsPID);

	WHILE(!(WaitEventTimeout(100))){
		//we have only one event - evIPC so return value may be 0 or evIPC but if received 0 it can mean
		//either MV terminated silently or it just hasn't done the work and we should wait. Test for it
			_p_info.GetInfo(MVsSlot);
			IF((_p_info.status_slot > 2)||(_p_info.ID != MVsPID)) return 0;
	}
//13.11.2008 4.26am Nable's fixes ( end1)  

//else we got the message. Process it.
   DSDWORD[pIPCbuffer] |= -1; //lock the buffer

   //the first dword of the message is frame count
   _FrameCountTemp = DSDWORD[pIPCbuffer+16]; //note that data of the first
   //message is located at offset 16 in IPC buffer;

   IF(_FrameCountTemp <= 1)  //see docs
    {
     ESI = pIPCbuffer+16+12;
     EDI = initial_values; //offset of CurrentImage structure

     //Left and top corner's coords (not used in many cases but who knows?)
     $MOVSD
     //Width and height
     $MOVSD
     //bpp
     $LODSD
     $movzx eax,ax
     CurrentImage.BitsPerPixel = EAX;
    }
   //see docs
   came_size = DSDWORD[pIPCbuffer+24]; //amount of useful data
   temp0 = came_size + 4096; //+4096 - some reserve
   realloc(temp0+4096, pIPCbuffer); //+4096 - some reserve
   registerIPCbuffer(pIPCbuffer, temp0); //re-register IPC buffer with a new size

   DSDWORD[pIPCbuffer+4]=8; //delete first message, at +4 in IPC buffer is a
   //relative pointer to free place

   DSDWORD[pIPCbuffer]=0; //unlock the buffer to receive second msg

//13.11.2008 4.26am Nable's fixes ( begin2)  
	WHILE(!(WaitEventTimeout(100))){
		//we have only one event - evIPC so return value may be 0 or evIPC but if received 0 it can mean
		//either MV terminated silently or it just hasn't done the work and we should wait. Test for it
			_p_info.GetInfo(MVsSlot);
			IF((_p_info.status_slot > 2)||(_p_info.ID != MVsPID)) return 0;
	}
//13.11.2008 4.26am Nable's fixes ( end2)  

//if we are here, then we received the second message. if FrameCount==1 then
//it's a pure image data (if BitsPerPixel==15, 16, 24 or 32) or
//(dword)sizeof(palette[]) then palette[] and then the image.
//Parse it as you like, here's my way:

   registerIPCbuffer(pIPCbuffer, 0); // there are no function 'unregister
   //IPC buffer' in Kolibri - so I have to use 'dark power'

   //shrink unneeded IPC data
   ECX = came_size;
   $SHR ECX,2
   ECX++; //ECX = number of useful dwords
   EDI = pIPCbuffer;
   ESI = EDI + 16;
   $CLD
   $REP $MOVSD

   //now we must interpret second message
   EDI = initial_values;
   IF(_FrameCountTemp <= 1)
    {
     IF(DSDWORD[EDI+24] > 8) //CurrentImage.BitsPerPixel
      {
       DSDWORD[EDI+20] = 0; //CurrentImage.pPalette=0
       DSDWORD[EDI+16] = pIPCbuffer; //CurrentImage.StartOfImage=pIPCbuffer
      }
     ELSE
      {
       EAX = pIPCbuffer + 4;
       DSDWORD[EDI+20] = EAX; //CurrentImage.pPalette=EAX
       EAX += DSDWORD[EAX-4];
       DSDWORD[EDI+16] = EAX; //CurrentImage.StartOfImage = EAX;
      };
    }
   ELSE
    {
     GetNthImageInfo(pIPCbuffer,EDI,0);
    };

   EBX = _FrameCountTemp;
   return pIPCbuffer;
}