main.c

/*
        Hello World example made by Aurelio Mannara for ctrulib
        This code was modified for the last time on: 12/12/2014 21:00 UTC+1

        This wouldn't be possible without the amazing work done by:
        -Smealum
        -fincs
        -WinterMute
        -yellows8
        -plutoo
        -mtheall
        -Many others who worked on 3DS and I'm surely forgetting about
*/

#include <3ds.h>
#include <stdio.h>
#include <stdlib.h>

#define OPENSHiT                                            \
  "ZPSSxUpRddddddddddidp,xEzpSo"                            \
  "ggzzSPSPzzddddda cz"                                     \
  "j\x01rW"                                                 \
  "gzzSPSzzPSPSiiiPdddcrJ\x06WSPWSPWWWWWW"                  \
  "gxtgx_zx,poSPP"                                          \
  "iiiiiiiiiiiiiiiiiiSPdiiiiiiiiiiiiiiiiiii"                \
  "c+J\x01WW"                                               \
  "gc3J\x02WWWizW"                                          \
  "xApAcAcdJ\x05WWWWWWWWidxMdgigdxA"                        \
  "gx\x18gx\x27gdgigx\x18gx\x16gx\x17giczj\x01rWzzz?zzePeP" \
  "caJ\x01WWWixMz"                                          \
  "xjcAJ\x01WWWixMz"                                        \
  "xycAJ\x01WWWixMz"                                        \
  "J\x01WWWiceiJ\x02WWWWWdxMz"                              \
  "WiidWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW"                  \
  "ZcaZcbZcdZcccAJ\x03WWWWWWdxMiz"                          \
  "didididiZcfZckWididcGJ\x04zWWWiiWWWWdxMizdxMxA"          \
  "c J\x02WWWWWxDMizdxMxAzx|"                               \
  "ccJ\x04WWWWWWWWWcoJ\x02WWWWx/iiiiiiiiiiiiiiii"           \
  "x]c\x00J\x01WWWWWWr"

struct node {
  char info;
  struct node* ptr;
}* top, *top1, *temp;

char topelement();
void push(char data);
char pop();
int empty();
void display();
void destroy();
int stack_count();
void create();
int vm(char* code);
char val(char* code, int pc);

int count = 0;
int winner = 0;

int main(int argc, char** argv) {
  gfxInitDefault();

  // Initialize console on top screen. Using NULL as the second argument tells
  // the console library to use the internal console structure as current one
  consoleInit(GFX_TOP, NULL);

  // Move the cursor to row 15 and column 19 and then prints "Hello World!"
  // To move the cursor you have to print "\x1b[r;cH", where r and c are
  // respectively
  // the row and column where you want your cursor to move
  // The top screen has 30 rows and 50 columns
  // The bottom screen has 30 rows and 40 columns
  create();
  vm(OPENSHiT);
  if (winner == 100) {
    printf("\x1b[15;19HWinner, please submit your flag!");
  } else {
    printf("\x1b[15;19HGo adjust your 3d slider and try again!");
  }

  printf("\x1b[29;15HPress Start to exit.");

  // Main loop
  while (aptMainLoop()) {
    // Scan all the inputs. This should be done once for each frame
    hidScanInput();

    // hidKeysDown returns information about which buttons have been just
    // pressed (and they weren't in the previous frame)
    u32 kDown = hidKeysDown();

    if (kDown & KEY_START) break;  // break in order to return to hbmenu

    // Flush and swap framebuffers
    gfxFlushBuffers();
    gfxSwapBuffers();

    // Wait for VBlank
    gspWaitForVBlank();
  }

  gfxExit();
  return 0;
}

int vm(char* code) {
  int pc = 0;
  int eq = 0;
  int zf = 0;
  int num = 0;
  int num2 = 0;
  int ii = 0;
  char str[1024] = {0};
  FILE* pFile;
  for (;;) {
    char instr = val(code, pc);
    ++pc;
    switch (instr) {
      case 'p':  // push
        num = val(code, pc);
        push(num);
        ++pc;
        break;
      case 'P':  // pop
        num = pop();
        break;
      case 'e':  // push "isempty"
        num = empty();
        push(num);
        break;
      case 'S':  // push stack size
        num = stack_count();
        push(num);
        break;
      case 'c':  // cmp <val>, next thing on stack
        num = val(code, pc);
        num2 = pop();
        ++pc;
        if (num == num2) {
          eq = 1;
        } else {
          eq = 0;
        }
        break;
      case 'a':  // add
        num = val(code, pc);
        num2 = pop();
        ++pc;
        push(num2 + num);
        break;
      case 's':  // subtract
        num = val(code, pc);
        num2 = pop();
        ++pc;
        push(num2 - num);
        break;
      case 'g':  // get from file
        num = fgetc(pFile);
        if (num == EOF) {
          return 1;
        }
        push(num);
        break;
      case 'w':  // write to stdout
        num = pop();
        break;
      case 'o':  // open file
        ii = 0;
        do {
          num = pop();
          str[ii] = num;
          ++ii;
        } while (num != '\0');
        pFile = fopen(str, "r");
        for (ii = 0; ii < 1024; ++ii) {
          str[ii] = '\0';
        }
        break;
      case 'r':  // ret
        return 0;
      case 'j':  // jump on equality
        num = val(code, pc);
        ++pc;
        if (eq) {
          pc = pc + num;
        }
        break;
      case 'J':  // jump on not equality
        num = val(code, pc);
        ++pc;
        if (!eq) {
          pc = pc + num;
        }
      case 'x':  // xor
        num = val(code, pc);
        ++pc;
        num2 = pop();
        push(num ^ num2);
        break;
      case 'm':  // multiply
        num = val(code, pc);
        ++pc;
        num2 = pop();
        push(num * num2);
        break;
      case 'z':  // zwap
        num = pop();
        num2 = pop();
        push(num);
        push(num2);
        break;
      case 'i':  // inc
        num = pop();
        ++num;
        push(num);
        break;
      case 'd':  // dec
        num = pop();
        --num;
        push(num);
        break;
      case 'W':  // win
        ++winner;
        break;
      case '?':  // close
        fclose(pFile);
        break;
      case 'Z':  // push zero
        push('\0');
        break;
    }
  }
}

char val(char* code, int pc) { return code[pc]; }

// empty stack
void create() { top = NULL; }
// stack size
int stack_count() { return count; }
// pushes onto stack
void push(char data) {
  if (top == NULL) {
    top = (struct node*)malloc(1 * sizeof(struct node));
    top->ptr = NULL;
    top->info = data;
  } else {
    temp = (struct node*)malloc(1 * sizeof(struct node));
    temp->ptr = top;
    temp->info = data;
    top = temp;
  }
  count++;
}

// prints for debugging
void display() {
  top1 = top;

  if (top1 == NULL) {
    return;
  }

  while (top1 != NULL) {
    top1 = top1->ptr;
  }
}

// stack pop
char pop() {
  char val;
  top1 = top;

  if (top1 == NULL) {
    return;
  } else {
    top1 = top1->ptr;
  }
  val = top->info;
  free(top);
  top = top1;
  count--;
  return val;
}

// peek without popping
char topelement() { return (top->info); }

// isempty?
int empty() { return top == NULL ? 1 : 0; }