lib/rle.c File Reference

#include "common.h"
#include "rle.h"

Include dependency graph for rle.c:

Go to the source code of this file.

Functions
static int	countSameAsStart (signed char *s, int max)
int	rleCompress (void *vIn, int inSize, signed char *out)
void	rleUncompress (signed char *in, int inSize, void *vOut, int outSize)
Variables
static char const	rcsid [] = "$Id: rle.c,v 1.6 2005/05/10 00:50:16 markd Exp $"

---

Function Documentation

static int countSameAsStart	(	signed char *	s,
		int	max
	)			[static]

Definition at line 11 of file rle.c.

Referenced by rleCompress().

{
signed char v = *s;
int i;
if (max > 127)
    max = 127;
for (i=1; i<max; ++i)
   if (s[i] != v)
       break;
return i;
}

Here is the caller graph for this function:

int rleCompress	(	void *	vIn,
		int	inSize,
		signed char *	out
	)

Definition at line 24 of file rle.c.

References countSameAsStart().

{
signed char *in = vIn;
signed char *endIn = in + inSize;
signed char *s = in, *d = out;
signed char *uncStart = in;
int uncSize, sameCount;
int sizeLeft;

while ((sizeLeft = (endIn - s)) != 0)
    {
    sameCount = countSameAsStart(s, sizeLeft);
    uncSize = s - uncStart;
    if (sameCount >= 3)
        {
        int uncSize = s - uncStart;
        while (uncSize > 0)
            {
            int size = uncSize;
            if (size > 127) size = 127;
            *d++ = size;
            memcpy(d, uncStart, size);
            d += size;
            uncSize -= size;
            uncStart += size;
            }
        *d++ = -sameCount;
        *d++ = *s;
        s += sameCount;
        uncStart = s;
        }
    else
        s += sameCount;
    }  
uncSize = s - uncStart;
while (uncSize > 0)
    {
    int size = uncSize;
    if (size > 127) size = 127;
    *d++ = size;
    memcpy(d, uncStart, size);
    d += size;
    uncSize -= size;
    uncStart += size;
    }
return d - out;
}

Here is the call graph for this function:

void rleUncompress	(	signed char *	in,
		int	inSize,
		void *	vOut,
		int	outSize
	)

Definition at line 74 of file rle.c.

{
int count;
signed char *out = vOut;
signed char *endOut = out + outSize;
#ifndef NDEBUG
signed char *endIn = in + inSize;
#endif

while (out < endOut)
     {
     count = *in++;
     if (count > 0)
          {
          memcpy(out, in, count);
          in += count;
          out += count;
          }
    else
          {
          count = -count;
          memset(out, *in++, count);
          out += count;
          }
          
    }
assert(out == endOut && in == endIn);
}

---

Variable Documentation

char const rcsid[] = "$Id: rle.c,v 1.6 2005/05/10 00:50:16 markd Exp $" [static]

Definition at line 9 of file rle.c.

---