Listing 3
/// VANYDEVDc.c
// -------------------------------------------- // Dynamically loadable VxD for ANYDEV board // -------------------------------------------- #define WIN32_LEAN_AND_MEAN // Excludes un-needed parts of windows.h #include "windows.h" #include <e:\ddk95\inc32\vmm.h> #include <e:\ddk95\inc32\vwin32.h> #include <e:\ddk95\inc32\debug.h> #include "VANYDEVD.H" // ------------------------------------- // Externs defined in assembly module // ------------------------------------- // These defined in assembly for the VMM.INC or VPICD.INC file inclusion extern DWORD GET_BD_MEM(void); extern DWORD Virt_IRQ(void); extern DWORD Get_IRQ_Status(void); extern void UNVirt_IRQ(DWORD IRQhandle); extern void End_ISR(DWORD IRQhandle); extern void Physically_Mask_IRQ(DWORD IRQhandle); extern void Physically_UNMask_IRQ(DWORD IRQhandle); // ------------------------ // PRAGMA for this DATA // ------------------------ // Establish segment #pragma data_seg ( "_LDATA","_LCODE") // ------------------------------------ // Data structures MUST be INITIALIZED // ------------------------------------ ADEV ANYDEVX = {0}; // Main structure for ANYDEV -- shared by app // ------------------------ // PRAGMAS for this CODE // ------------------------ // Establish segment #pragma code_seg ( "_LTEXT", "_LCODE" ) //No stack checking for routines in this module #pragma check_stack(off) // ---------------- // Disable hardware // ---------------- void Disable_AnyDev(void) { //This would likely be a port WRITE to DISABLE the board's interrupt } // ---------------- // Enable hardware // ---------------- void Enable_AnyDev(void) { //This would likely be a port WRITE to ENABLE the board's interrupt } // -------------------------- // ISR Processing for ANYDEV // -------------------------- void Process_ISR(void) { //This is where the user might SET FLAGS and indicators in the ANYDEVX structure //in order to notify the application that data is available below 1MB } // ----------------- // ISR for ANYDEV // ----------------- void _declspec(naked)ISR_ANYDEV(void) { // Save registers _asm sti _asm pushad _asm pushfd //Process the ISR Process_ISR(); //End ISR _asm clc End_ISR(ANYDEVX.IRQhandle); //Set GOOD return code _asm clc //Restore saved registers _asm popfd _asm popad _asm ret; } // ------------------- // Virtualize the IRQ // ------------------- DWORD CVirt_IRQ(void) { // If in use by an instance of this program, RETURN with BAD code if (ANYDEVX.IRQcount) return (BOGUSADDRESS); // If in use by another program, RETURN with BAD code ANYDEVX.IRQstatus = Get_IRQ_Status(); if (ANYDEVX.IRQstatus) return (BOGUSADDRESS); // If IRQ NOT in use this point is reached // Set BAD return code ANYDEVX.IRQhandle = BOGUSADDRESS; // Disable ANYDEV hardware Disable_AnyDev(); // Get global memory address below 1mb ANYDEVX.Global_addr_1MB = GET_BD_MEM(); if (ANYDEVX.Global_addr_1MB != BOGUSADDRESS) { // Virtualize the IRQ ANYDEVX.IRQhandle = Virt_IRQ(); if (ANYDEVX.IRQhandle != BOGUSADDRESS) { // unmask the IRQ, set OK flag & increment IRQ count Physically_UNMask_IRQ(ANYDEVX.IRQhandle); ANYDEVX.IRQflags |= IRQ_VIRT_OK; ++(ANYDEVX.IRQcount); } } return(ANYDEVX.IRQhandle); } // ---------------------- // UN Virtualize the IRQ // ---------------------- void CUNVirt_IRQ(DWORD IRQhandle) { // if IRQ has been successfully virtualized if ((ANYDEVX.IRQhandle != 0) && (ANYDEVX.IRQhandle != BOGUSADDRESS)) { // Physically mask the IRQ and UN virtualized it Physically_Mask_IRQ(ANYDEVX.IRQhandle); UNVirt_IRQ(ANYDEVX.IRQhandle); } // Set UNvirtualized flags and indicators ANYDEVX.IRQhandle = BOGUSADDRESS; ANYDEVX.IRQflags &= ~IRQ_VIRT_OK; return; } // --------------------------------------- // Set Good Return code for DIOC requests // --------------------------------------- void _declspec(naked)GoodReturnDIOC(void) { // Clear eax and carry flag for GOOD return _asm xor eax,eax _asm clc _asm ret; } // --------------------------------------- // Set Bad Return code for DIOC requests // --------------------------------------- void _declspec(naked) BadReturnDIOC(void) { // NOTE: 50 is a FCN NOT SUPPORTED code -- ok to use // SET carry flag for BAD return _asm mov eax,50 _asm stc _asm ret; } // ------------------------------ // Routine for ANYDEV Device UNINIT // ------------------------------ void CVANYDEVD_Device_UNInit() { // Disable ANYDEV, Unvirtualize IRQ, set GOOD return code Disable_AnyDev(); CUNVirt_IRQ(ANYDEVX.IRQhandle); GoodReturnDIOC(); return; } // ------------------------------ // Routine for ANYDEV Device INIT // ------------------------------ void CVANYDEVD_Device_Init() { DWORD retcode; // Try to virtualize the IRQ retcode = CVirt_IRQ(); // Set GOOD or BAD return code based on success if (retcode == BOGUSADDRESS) BadReturnDIOC(); else GoodReturnDIOC(); return; } // -------------------------------- // Routine for ANYDEV Device IO ctrl // -------------------------------- void CVANYDEVD_Device_IOctrl(PDIOCPARAMETERS ptr) { DWORD *obuf1; // Field the DEV IO requests from VMM switch(ptr->dwIoControlCode) { case(VANYDEVD_INIT_ADEV_HARDWARE): ANYDEVX.flags = 0; //User likely to require other initialization here break; case(VANYDEVD_GRAB_ADDRESSES): // Point to Output buffer obuf1 = (DWORD *) ptr->lpvOutBuffer; // Return GLOBAL 1MB addr, addr of data structure // and return indicators of IRQ virtuaization request *obuf1 = ANYDEVX.Global_addr_1MB; *(obuf1+1) = (DWORD) &ANYDEVX; *(obuf1+2) = (DWORD) ANYDEVX.IRQhandle; *(obuf1+3) = (DWORD) ANYDEVX.IRQflags; //User might want to return other/different values here break; case(VANYDEVD_ENABLE_ANYDEV_HDWR): //Call routine to enable interrupt Enable_AnyDev(); break; case(VANYDEVD_DISABLE_ANYDEV_HWR): //Call routine to disable interrupt Disable_AnyDev(); break; //The below DIOC_GETVERSION is a part of the dynamic load protocol //It MUST return a GOOD code (all codes here use GoodReturnDIOC() case(DIOC_GETVERSION): case(DIOC_CLOSEHANDLE): default: break; } GoodReturnDIOC(); return; }
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