grayscreenshotlib.c

#include "grayscreenshotlib.h"

int file_handle, time, n_screen;

void gsl_init(int n_screenshot)
{
    unsigned short filename[] = {'\\','\\','c','r','d','0','\\','M','O','V','I','E','.','g','s','l',0};
    gsl_CreateFile(filename, 2048*n_screenshot);
    file_handle = gsl_OpenFile(filename, 2);
    n_screen = n_screenshot;
    time = 0;
}

void gsl_quit()
{
    gsl_CloseFile(file_handle);
    n_screen = 0;
}

void gsl_screenshot(const unsigned char* light_buffer, const unsigned char* dark_buffer)
{
    if(n_screen) {
        if(gsl_GetTicks()-time > 6) {
            time = gsl_GetTicks();
            gsl_WriteFile(file_handle, light_buffer, 1024);
            gsl_WriteFile(file_handle, dark_buffer, 1024);
            n_screen--;
        }
    }
}

/* syscalls */

const int SysCallCode[] = {0xD201422B,0x60F20000,0x80010070};
static int (*SysCall)( int R4, int R5, int R6, int R7, int FNo ) = (void*)&SysCallCode;

static int gsl_CreateFile(const unsigned short *filename, int size) {
    return (int)((*SysCall)( (int)filename, 1, (int)&size, 0, 0x0434 ));
}

static int gsl_WriteFile(int handle, void* buffer, int size) {
    if (handle & 0xF000000) { return (int)((*SysCall)( handle, (int)buffer, size, 0, 0x0435 )); }
    else { return -1; }
}

static int gsl_OpenFile(const unsigned short *filename, int mode) {
    return (int)((*SysCall)( (int)filename, mode, 0, 0, 0x042C ));
}

static int gsl_CloseFile(int handle) {
    if (handle & 0xF000000) { return (int)((*SysCall)( handle, 0, 0, 0, 0x042D )); }
    else { return -1; }
}

static int gsl_GetTicks(void) {
    return (int)((*SysCall)( 0, 0, 0, 0, 0x003B ));
}