static void PMAPI lockPMHandlers(void) { static int locked = 0; int stat; PM_lockHandle lh; /* Unused in DOS */ /* Lock all of the code and data used by our protected mode interrupt * handling routines, so that it will continue to work correctly * under real mode. */ if (!locked) { PM_saveDS(); stat = !PM_lockDataPages(&globalDataStart-2048,4096,&lh); stat |= !PM_lockDataPages(&_PM_pmdosDataStart,(int)&_PM_pmdosDataEnd - (int)&_PM_pmdosDataStart,&lh); stat |= !PM_lockCodePages((__codePtr)_PM_pmdosCodeStart,(int)_PM_pmdosCodeEnd-(int)_PM_pmdosCodeStart,&lh); stat |= !PM_lockDataPages(&_PM_DMADataStart,(int)&_PM_DMADataEnd - (int)&_PM_DMADataStart,&lh); stat |= !PM_lockCodePages((__codePtr)_PM_DMACodeStart,(int)_PM_DMACodeEnd-(int)_PM_DMACodeStart,&lh); if (stat) { printf("Page locking services failed - interrupt handling not safe!\n"); exit(1); } locked = 1; } }
int main(void) { long oldCount; PM_lockHandle lh; printf("Program running in "); switch (PM_getModeType()) { case PM_realMode: printf("real mode.\n\n"); break; case PM_286: printf("16 bit protected mode.\n\n"); break; case PM_386: printf("32 bit protected mode.\n\n"); break; } /* Install our timer handler and lock handler pages in memory. It is * difficult to get the size of a function in C, but we know our * function is well less than 100 bytes (and an entire 4k page will * need to be locked by the server anyway). */ PM_lockCodePages((__codePtr)RTCHandler,100,&lh); PM_lockDataPages((void*)&count,sizeof(count),&lh); PM_installBreakHandler(); /* We *DONT* want Ctrl-Breaks! */ PM_setRealTimeClockHandler(RTCHandler,128); printf("RealTimeClock interrupt handler installed - Hit ESC to exit\n"); oldCount = count; while (1) { if (PM_kbhit() && (PM_getch() == 0x1B)) break; if (count != oldCount) { printf("Tick, Tock: %ld\n", count); oldCount = count; } } PM_restoreRealTimeClockHandler(); PM_restoreBreakHandler(); PM_unlockDataPages((void*)&count,sizeof(count),&lh); PM_unlockCodePages((__codePtr)RTCHandler,100,&lh); printf("RealTimeClock handler was called %ld times\n", count); return 0; }
int main(void) { int ch; PM_lockHandle lh; printf("Program running in "); switch (PM_getModeType()) { case PM_realMode: printf("real mode.\n\n"); break; case PM_286: printf("16 bit protected mode.\n\n"); break; case PM_386: printf("32 bit protected mode.\n\n"); break; } /* Install our timer handler and lock handler pages in memory. It is * difficult to get the size of a function in C, but we know our * function is well less than 100 bytes (and an entire 4k page will * need to be locked by the server anyway). */ PM_lockCodePages((__codePtr)keyHandler,100,&lh); PM_lockDataPages((void*)&count,sizeof(count),&lh); PM_installBreakHandler(); /* We *DONT* want Ctrl-Breaks! */ PM_setKeyHandler(keyHandler); printf("Keyboard interrupt handler installed - Type some characters and\n"); printf("hit ESC to exit\n"); while ((ch = PM_getch()) != 0x1B) { printf("%c", ch); fflush(stdout); } PM_restoreKeyHandler(); PM_restoreBreakHandler(); PM_unlockDataPages((void*)&count,sizeof(count),&lh); PM_unlockCodePages((__codePtr)keyHandler,100,&lh); printf("\n\nKeyboard handler was called %ld times\n", count); return 0; }
/**************************************************************************** REMARKS: Allocates a page aligned and page sized block of memory ****************************************************************************/ void * PMAPI PM_allocPage( ibool locked) { pageblock *block; void *p; PM_lockHandle lh; /* Scan the block list looking for any free blocks. Allocate a new * page block if no free blocks are found. */ for (block = pageBlocks; block != NULL; block = block->next) { if (block->freeCount) break; } if (block == NULL && (block = PM_addNewPageBlock()) == NULL) return NULL; block->freeCount--; p = block->freeList; block->freeList = FREELIST_NEXT(p); if (locked) PM_lockDataPages(p,PM_PAGE_SIZE,&lh); return p; }