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/* Copyright (C) 2007 Josh MacDonald */
#include <stdio.h>
#define PAGE_SIZE 4096
#define SPACE_MAX 131072 // how much memory per process
#define OUTPUT_MAX 1024 // max size for output
#define XD3_ALLOCSIZE 256 // internal size for various buffers
#define IOPT_SIZE 128 // instruction buffer
// SPACE_MAX of 32K is sufficient for most inputs with XD3_COMPLEVEL_1
// XD3_COMPLEVEL_9 requires about 4x more space than XD3_COMPLEVEL_1
#include "xdelta3.h"
#include "xdelta3.c"
typedef struct _context {
uint8_t *buffer;
int allocated;
} context_t;
static int max_allocated = 0;
void*
process_alloc (void* opaque, usize_t items, usize_t size)
{
context_t *ctx = (context_t*) opaque;
usize_t t = items * size;
void *ret;
if (ctx->allocated + t > SPACE_MAX)
{
return NULL;
}
ret = ctx->buffer + ctx->allocated;
ctx->allocated += t;
return ret;
}
void
process_free (void* opaque, void *ptr)
{
}
int
process_page (int is_encode,
int (*func) (xd3_stream *),
const uint8_t *input,
usize_t input_size,
const uint8_t *source,
uint8_t *output,
usize_t *output_size,
usize_t output_size_max,
int flags) {
/* On my x86 this is 1072 of objects on the stack */
xd3_stream stream;
xd3_config config;
xd3_source src;
context_t *ctx = calloc(SPACE_MAX, 1);
int ret;
if (ctx == NULL)
{
printf("calloc failed\n");
return -1;
}
ctx->buffer = (uint8_t*)ctx;
ctx->allocated = sizeof(*ctx);
config.flags = flags;
config.winsize = PAGE_SIZE;
config.sprevsz = PAGE_SIZE;
config.srcwin_maxsz = PAGE_SIZE;
config.iopt_size = IOPT_SIZE;
config.alloc = &process_alloc;
config.freef = &process_free;
config.opaque = (void*) ctx;
src.size = PAGE_SIZE;
src.blksize = PAGE_SIZE;
src.onblk = PAGE_SIZE;
src.curblk = source;
src.curblkno = 0;
if ((ret = xd3_config_stream (&stream, &config)) != 0 ||
(ret = xd3_set_source (&stream, &src)) != 0 ||
(ret = xd3_process_stream (is_encode,
&stream,
func, 1,
input, input_size,
output, output_size,
output_size_max)) != 0)
{
if (stream.msg != NULL)
{
fprintf(stderr, "stream message: %s\n", stream.msg);
}
}
xd3_free_stream (&stream);
if (max_allocated < ctx->allocated)
{
max_allocated = ctx->allocated;
fprintf(stderr, "max allocated %d\n", max_allocated);
}
free(ctx);
return ret;
}
int test(int stride, int encode_flags)
{
uint8_t frompg[PAGE_SIZE];
uint8_t topg[PAGE_SIZE];
uint8_t output[OUTPUT_MAX];
uint8_t reout[PAGE_SIZE];
usize_t output_size;
usize_t re_size;
int i, j, ret;
for (i = 0; i < PAGE_SIZE; i++)
{
topg[i] = frompg[i] = (rand() >> 3 ^ rand() >> 6 ^ rand() >> 9);
}
// change 1 byte every stride
if (stride > 0)
{
for (j = stride; j <= PAGE_SIZE; j += stride)
{
topg[j - 1] ^= 0xff;
}
}
if ((ret = process_page (1, xd3_encode_input,
topg, PAGE_SIZE,
frompg, output,
&output_size, OUTPUT_MAX,
encode_flags)) != 0)
{
fprintf (stderr, "encode failed: stride %u flags 0x%x\n", stride, encode_flags);
return ret;
}
if ((ret = process_page (0, xd3_decode_input,
output, output_size,
frompg, reout,
&re_size, PAGE_SIZE,
0)) != 0)
{
fprintf (stderr, "decode failed: stride %u output_size %u flags 0x%x\n",
stride, output_size, encode_flags);
return ret;
}
if (output_size > OUTPUT_MAX || re_size != PAGE_SIZE)
{
fprintf (stderr, "internal error: %u != %u\n", output_size, re_size);
return -1;
}
for (i = 0; i < PAGE_SIZE; i++)
{
if (reout[i] != topg[i])
{
fprintf (stderr, "encode-decode error: position %d\n", i);
return -1;
}
}
fprintf(stderr, "stride %d flags 0x%x size %u ", stride, encode_flags, output_size);
fprintf(stderr, "%s\n", (ret == 0) ? "OK" : "FAIL");
return 0;
}
int main()
{
int stride;
int level;
for (level = 1; level < 10; level = (level == 1 ? 3 : level + 3))
{
int lflag = level << XD3_COMPLEVEL_SHIFT;
for (stride = 2; stride <= PAGE_SIZE; stride += 2)
{
test(stride, lflag);
test(stride, lflag | XD3_SEC_DJW);
}
}
return 0;
}
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