c - BZip2 解压非文件数据时不会出现错误？

Question

所以我有这段代码，它生成一系列字节，然后用 bzip2 对其进行压缩。我怎样才能解压它们？普通(右键单击)解压缩会导致损坏，可能是因为没有文件开头或结尾。它需要用某种编程语言来完成，最好是 C#、C、C++、Java 或 Python。另外，我需要读取解压缩流中的二进制数据。我将不胜感激任何帮助。

这是代码，它填充一个数组并在最后使用 BZ2_bzBuffToBuffCompress 对其进行压缩:

void *build_save(int *size, int x0, int y0, int w, int h,
         unsigned char bmap[YRES/CELL][XRES/CELL], 
         float fvx[YRES/CELL][XRES/CELL], 
         float fvy[YRES/CELL][XRES/CELL], sign signs[MAXSIGNS],
         void* partsptr)
{
  unsigned char *d=calloc(1,3*(XRES/CELL)*(YRES/CELL)+(XRES*YRES)*15+MAXSIGNS*262), *c;
  int i,j,x,y,p=0,*m=calloc(XRES*YRES, sizeof(int));
  int bx0=x0/CELL, by0=y0/CELL, bw=(w+CELL-1)/CELL, bh=(h+CELL-1)/CELL;
  particle *parts = partsptr;

  // normalize coordinates
  x0 = bx0*CELL;
  y0 = by0*CELL;
  w = bw *CELL;
  h = bh *CELL;

  // save the required air state
  for (y=by0; y<by0+bh; y++)
    for (x=bx0; x<bx0+bw; x++)
      d[p++] = bmap[y][x];
  for (y=by0; y<by0+bh; y++)
    for (x=bx0; x<bx0+bw; x++)
      if (bmap[y][x]==WL_FAN||bmap[y][x]==4){
    i = (int)(fvx[y][x]*64.0f+127.5f);
      if (i<0) i=0;
      if (i>255) i=255;
      d[p++] = i;
      }
  for (y=by0; y<by0+bh; y++)
    for (x=bx0; x<bx0+bw; x++)
      if (bmap[y][x]==WL_FAN||bmap[y][x]==4){
    i = (int)(fvy[y][x]*64.0f+127.5f);
    if (i<0) i=0;
    if (i>255) i=255;
    d[p++] = i;
      }

  // save the particle map
  for (i=0; i<NPART; i++)
    if (parts[i].type) {
    x = (int)(parts[i].x+0.5f);
    y = (int)(parts[i].y+0.5f);
    if (x>=x0 && x<x0+w && y>=y0 && y<y0+h) {
      if (!m[(x-x0)+(y-y0)*w] ||
          parts[m[(x-x0)+(y-y0)*w]-1].type == PT_PHOT ||
          parts[m[(x-x0)+(y-y0)*w]-1].type == PT_NEUT)
        m[(x-x0)+(y-y0)*w] = i+1;
    }
    }
  for (j=0; j<w*h; j++) {
    i = m[j];
    if (i)
      d[p++] = parts[i-1].type;
    else
      d[p++] = 0;
  }

  // save particle properties
  for (j=0; j<w*h; j++){
    i = m[j];
    if (i)
      {
    i--;
    x = (int)(parts[i].vx*16.0f+127.5f);
    y = (int)(parts[i].vy*16.0f+127.5f);
    if (x<0) x=0;
    if (x>255) x=255;
    if (y<0) y=0;
    if (y>255) y=255;
    d[p++] = x;
    d[p++] = y;
      }
  }
  for (j=0; j<w*h; j++){
    i = m[j];
    if (i) {
      //Everybody loves a 16bit int
      //d[p++] = (parts[i-1].life+3)/4;
      int ttlife = (int)parts[i-1].life;
      d[p++] = ((ttlife&0xFF00)>>8);
      d[p++] = (ttlife&0x00FF);
    }
  }
  for (j=0; j<w*h; j++){
    i = m[j];
    if (i) {
      //Now saving tmp!
      //d[p++] = (parts[i-1].life+3)/4;
      int tttmp = (int)parts[i-1].tmp;
      d[p++] = ((tttmp&0xFF00)>>8);
      d[p++] = (tttmp&0x00FF);
        }
  }
  for (j=0; j<w*h; j++){
    i = m[j];
    if (i) {
      //Save colour (ALPHA)
      d[p++] = (parts[i-1].dcolour&0xFF000000)>>24;
    }
  }
  for (j=0; j<w*h; j++){
    i = m[j];
    if (i) {
      //Save colour (RED)
      d[p++] = (parts[i-1].dcolour&0x00FF0000)>>16;
    }
  }
  for (j=0; j<w*h; j++){
    i = m[j];
    if (i) {
      //Save colour (GREEN)
      d[p++] = (parts[i-1].dcolour&0x0000FF00)>>8;
    }
  }
  for (j=0; j<w*h; j++){
    i = m[j];
    if (i) {
      //Save colour (BLUE)
          d[p++] = (parts[i-1].dcolour&0x000000FF);
    }
  }
  for (j=0; j<w*h; j++){
    i = m[j];
    if (i){
      // New Temperature saving uses a 16bit unsigned int for
      // temperatures, giving a precision of 1 degree versus 36 for the old
      // format
      int tttemp = (int)parts[i-1].temp;
      d[p++] = ((tttemp&0xFF00)>>8);
      d[p++] = (tttemp&0x00FF);
    }
  }
  for (j=0; j<w*h; j++) {
    i = m[j];
    if (i && (parts[i-1].type==PT_CLNE || parts[i-1].type==PT_PCLN || 
          parts[i-1].type==PT_BCLN || parts[i-1].type==PT_SPRK || 
          parts[i-1].type==PT_LAVA || parts[i-1].type==PT_PIPE))
      d[p++] = parts[i-1].ctype;
  }

  j = 0;
  for (i=0; i<MAXSIGNS; i++)
    if (signs[i].text[0] &&
    signs[i].x>=x0 && signs[i].x<x0+w &&
    signs[i].y>=y0 && signs[i].y<y0+h)
      j++;
  d[p++] = j;
  for (i=0; i<MAXSIGNS; i++)
    if (signs[i].text[0] &&
    signs[i].x>=x0 && signs[i].x<x0+w &&
    signs[i].y>=y0 && signs[i].y<y0+h){
      d[p++] = (signs[i].x-x0);
      d[p++] = (signs[i].x-x0)>>8;
          d[p++] = (signs[i].y-y0);
      d[p++] = (signs[i].y-y0)>>8;
      d[p++] = signs[i].ju;
      x = strlen(signs[i].text);
      d[p++] = x;
      memcpy(d+p, signs[i].text, x);
      p+=x;
    }

  i = (p*101+99)/100 + 612;
  c = malloc(i);

  //New file header uses PSv, replacing fuC. This is to detect if the
  //client uses a new save format for temperatures
  //This creates a problem for old clients, that display and "corrupt"
  //error instead of a "newer version" error

  c[0] = 0x50; //0x66;
  c[1] = 0x53; //0x75;
  c[2] = 0x76; //0x43;
  c[3] = legacy_enable|((sys_pause<<1)&0x02)|((gravityMode<<2)&0x0C)|((airMode<<4)&0x70)|((ngrav_enable<<7)&0x80);
  c[4] = SAVE_VERSION;
  c[5] = CELL;
  c[6] = bw;
  c[7] = bh;
  c[8] = p;
  c[9] = p >> 8;
  c[10] = p >> 16;
  c[11] = p >> 24;

  i -= 12;

  if (BZ2_bzBuffToBuffCompress((char *)(c+12), (unsigned *)&i, (char *)d, p, 9, 0, 0) != BZ_OK){
    free(d);
    free(c);
    free(m);
    return NULL;
  }
  free(d);
  free(m);

  *size = i+12;
  return c;
}

Answer 1

您必须从 libbzip2 库调用函数 BZ2_bzBuffToBuffDecompress http://www.bzip.org/1.0.6/bzip2-1.0.6.tar.gz

这里是文档: http://www.bzip.org/1.0.3/html/util-fns.html

您可以像这样调用该代码:

#include <malloc.h>


int size;
void *buf=build_save(&size, ... add all the parameters ... );

enum{DEST=100000};
char*dest=malloc(DEST);
BZ2_bzBuffToBuffDecompress( dest, 
                            DEST, //unsigned int* destLen,
                            buf+12, //char*         source,
                            size-12, //unsigned int  sourceLen,
                            int           small,
                            int           verbosity );

我意识到您没有提供足够的信息。 尝试搜索您的电话来源

BZ2_bzDecompressInit ( bz_stream *strm, int verbosity, int small );

您需要知道解压缩的参数 verbosity 和small。