//========================================================================

//

// FoFiBase.cc

//

// Copyright 1999-2003 Glyph & Cog, LLC

//

//========================================================================

#include <aconf.h>

#ifdef USE_GCC_PRAGMAS

#pragma implementation

#endif

#include <stdio.h>

#include <limits.h>

#include "gmem.h"

#include "gmempp.h"

#include "FoFiBase.h"

//------------------------------------------------------------------------

// FoFiBase

//------------------------------------------------------------------------

FoFiBase::FoFiBase(char *fileA, int lenA, GBool freeFileDataA) {

  fileData = file = (Guchar *)fileA;

  len = lenA;

  freeFileData = freeFileDataA;

}

FoFiBase::~FoFiBase() {

  if (freeFileData) {

    gfree(fileData);

  }

}

char *FoFiBase::readFile(char *fileName, int *fileLen) {

  FILE *f;

  char *buf;

  int n;

  if (!(f = fopen(fileName, "rb"))) {

    return NULL;

  }

  fseek(f, 0, SEEK_END);

  n = (int)ftell(f);

  if (n < 0) {

    fclose(f);

    return NULL;

  }

  fseek(f, 0, SEEK_SET);

  buf = (char *)gmalloc(n);

  if ((int)fread(buf, 1, n, f) != n) {

    gfree(buf);

    fclose(f);

    return NULL;

  }

  fclose(f);

  *fileLen = n;

  return buf;

}

int FoFiBase::getS8(int pos, GBool *ok) {

  int x;

  if (pos < 0 || pos >= len) {

    *ok = gFalse;

    return 0;

  }

  x = file[pos];

  if (x & 0x80) {

    x |= ~0xff;

  }

  return x;

}

int FoFiBase::getU8(int pos, GBool *ok) {

  if (pos < 0 || pos >= len) {

    *ok = gFalse;

    return 0;

  }

  return file[pos];

}

int FoFiBase::getS16BE(int pos, GBool *ok) {

  int x;

  if (pos < 0 || pos > INT_MAX - 1 || pos+1 >= len) {

    *ok = gFalse;

    return 0;

  }

  x = file[pos];

  x = (x << 8) + file[pos+1];

  if (x & 0x8000) {

    x |= ~0xffff;

  }

  return x;

}

int FoFiBase::getU16BE(int pos, GBool *ok) {

  int x;

  if (pos < 0 || pos > INT_MAX - 1 || pos+1 >= len) {

    *ok = gFalse;

    return 0;

  }

  x = file[pos];

  x = (x << 8) + file[pos+1];

  return x;

}

int FoFiBase::getS32BE(int pos, GBool *ok) {

  int x;

  if (pos < 0 || pos > INT_MAX - 3 || pos+3 >= len) {

    *ok = gFalse;

    return 0;

  }

  x = file[pos];

  x = (x << 8) + file[pos+1];

  x = (x << 8) + file[pos+2];

  x = (x << 8) + file[pos+3];

  if (x & 0x80000000) {

    x |= ~0xffffffff;

  }

  return x;

}

Guint FoFiBase::getU32BE(int pos, GBool *ok) {

  Guint x;

  if (pos < 0 || pos > INT_MAX - 3 || pos+3 >= len) {

    *ok = gFalse;

    return 0;

  }

  x = file[pos];

  x = (x << 8) + file[pos+1];

  x = (x << 8) + file[pos+2];

  x = (x << 8) + file[pos+3];

  return x;

}

Guint FoFiBase::getU32LE(int pos, GBool *ok) {

  Guint x;

  if (pos < 0 || pos > INT_MAX - 3 || pos+3 >= len) {

    *ok = gFalse;

    return 0;

  }

  x = file[pos+3];

  x = (x << 8) + file[pos+2];

  x = (x << 8) + file[pos+1];

  x = (x << 8) + file[pos];

  return x;

}

Guint FoFiBase::getUVarBE(int pos, int size, GBool *ok) {

  Guint x;

  int i;

  if (pos < 0 || pos > INT_MAX - size || pos + size > len) {

    *ok = gFalse;

    return 0;

  }

  x = 0;

  for (i = 0; i < size; ++i) {

    x = (x << 8) + file[pos + i];

  }

  return x;

}

GBool FoFiBase::checkRegion(int pos, int size) {

  return pos >= 0 &&

         size >= 0 &&

         size <= INT_MAX - pos &&

         pos + size <= len;

}