aboutsummaryrefslogtreecommitdiffstats
path: root/crypto/openssl/crypto/comp/c_rle.c
blob: efd366fa2239aa08594f50c3d3fe4a266164be55 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <openssl/objects.h>
#include <openssl/comp.h>

static int rle_compress_block(COMP_CTX *ctx, unsigned char *out,
	unsigned int olen, unsigned char *in, unsigned int ilen);
static int rle_expand_block(COMP_CTX *ctx, unsigned char *out,
	unsigned int olen, unsigned char *in, unsigned int ilen);

static COMP_METHOD rle_method={
	NID_rle_compression,
	LN_rle_compression,
	NULL,
	NULL,
	rle_compress_block,
	rle_expand_block,
	NULL,
	NULL,
	};

COMP_METHOD *COMP_rle(void)
	{
	return(&rle_method);
	}

static int rle_compress_block(COMP_CTX *ctx, unsigned char *out,
	     unsigned int olen, unsigned char *in, unsigned int ilen)
	{
	/* int i; */

	if (olen < (ilen+1))
		{
		/* ZZZZZZZZZZZZZZZZZZZZZZ */
		return(-1);
		}

	*(out++)=0;
	memcpy(out,in,ilen);
	return(ilen+1);
	}

static int rle_expand_block(COMP_CTX *ctx, unsigned char *out,
	     unsigned int olen, unsigned char *in, unsigned int ilen)
	{
	int i;

	if (olen < (ilen-1))
		{
		/* ZZZZZZZZZZZZZZZZZZZZZZ */
		return(-1);
		}

	i= *(in++);
	if (i == 0)
		{
		memcpy(out,in,ilen-1);
		}
	return(ilen-1);
	}