void crunch_backwards(struct membuf *inbuf,
struct membuf *outbuf,
struct crunch_options *options, /* IN */
struct crunch_info *info) /* OUT */
{
static match_ctx ctx;
encode_match_data emd;
search_nodep snp;
int outlen;
int safety;
int copy_used;
if(options == NULL)
{
options = default_options;
}
outlen = membuf_memlen(outbuf);
emd->out = NULL;
optimal_init(emd);
LOG(LOG_NORMAL,
("\nPhase 1: Instrumenting file"
"\n-----------------------------\n"));
LOG(LOG_NORMAL, (" Length of indata: %d bytes.\n", membuf_memlen(inbuf)));
match_ctx_init(ctx, inbuf, options->max_len, options->max_offset,
options->use_imprecise_rle);
LOG(LOG_NORMAL, (" Instrumenting file, done.\n"));
emd->out = NULL;
optimal_init(emd);
LOG(LOG_NORMAL,
("\nPhase 2: Calculating encoding"
"\n-----------------------------\n"));
snp = do_compress(ctx, emd, options->exported_encoding,
options->max_passes, options->use_literal_sequences);
LOG(LOG_NORMAL, (" Calculating encoding, done.\n"));
LOG(LOG_NORMAL,
("\nPhase 3: Generating output file"
"\n------------------------------\n"));
LOG(LOG_NORMAL, (" Encoding: %s\n", optimal_encoding_export(emd)));
safety = do_output(ctx, snp, emd, optimal_encode, outbuf, ©_used);
LOG(LOG_NORMAL, (" Length of crunched data: %d bytes.\n",
membuf_memlen(outbuf) - outlen));
optimal_free(emd);
search_node_free(snp);
match_ctx_free(ctx);
if(info != NULL)
{
info->literal_sequences_used = copy_used;
info->needed_safety_offset = safety;
}
}
int exomizer(unsigned char *srcbuf, int len, int load, int start, unsigned char *destbuf)
{
int destlen;
int max_offset = 65536;
int max_passes = 65536;
static match_ctx ctx;
encode_match_data emd;
encode_match_priv optimal_priv;
search_nodep snp;
match_ctx_init(ctx, srcbuf, len, max_offset);
emd->out = NULL;
emd->priv = optimal_priv;
optimal_init(emd);
snp = do_compress(ctx, emd, max_passes);
destlen = generate_output(ctx, snp, sfx_c64ne, optimal_encode, emd,
load, len, start, destbuf);
optimal_free(emd);
#if 0 /* RH */
search_node_free(snp);
#endif /* RH */
match_ctx_free(ctx);
return destlen;
}
search_nodep
do_compress(match_ctx ctx, encode_match_data emd,
const char *exported_encoding,
int max_passes,
int use_literal_sequences)
{
matchp_cache_enum mpce;
matchp_snp_enum snpe;
search_nodep snp;
search_nodep best_snp;
int pass;
float size;
float old_size;
char prev_enc[100];
const char *curr_enc;
pass = 1;
prev_enc[0] = '\0';
LOG(LOG_NORMAL, (" pass %d: ", pass));
if(exported_encoding != NULL)
{
LOG(LOG_NORMAL, ("importing %s\n", exported_encoding));
optimal_encoding_import(emd, exported_encoding);
}
else
{
LOG(LOG_NORMAL, ("optimizing ..\n"));
matchp_cache_get_enum(ctx, mpce);
optimal_optimize(emd, matchp_cache_enum_get_next, mpce);
}
best_snp = NULL;
old_size = 100000000.0;
for (;;)
{
snp = search_buffer(ctx, optimal_encode, emd,
use_literal_sequences);
if (snp == NULL)
{
LOG(LOG_ERROR, ("error: search_buffer() returned NULL\n"));
exit(-1);
}
size = snp->total_score;
LOG(LOG_NORMAL, (" size %0.1f bits ~%d bytes\n",
size, (((int) size) + 7) >> 3));
if (size >= old_size)
{
search_node_free(snp);
break;
}
if (best_snp != NULL)
{
search_node_free(best_snp);
}
best_snp = snp;
old_size = size;
++pass;
if(pass > max_passes)
{
break;
}
optimal_free(emd);
optimal_init(emd);
LOG(LOG_NORMAL, (" pass %d: optimizing ..\n", pass));
matchp_snp_get_enum(snp, snpe);
optimal_optimize(emd, matchp_snp_enum_get_next, snpe);
curr_enc = optimal_encoding_export(emd);
if (strcmp(curr_enc, prev_enc) == 0)
{
break;
}
strcpy(prev_enc, curr_enc);
}
return best_snp;
}
static
search_nodep
do_compress(match_ctx ctx, encode_match_data emd, int max_passes)
{
matchp_cache_enum mpce;
matchp_snp_enum snpe;
search_nodep snp;
search_nodep best_snp;
int pass;
float old_size;
pass = 1;
matchp_cache_get_enum(ctx, mpce);
optimal_optimize(emd, matchp_cache_enum_get_next, mpce);
best_snp = NULL;
old_size = 1000000.0;
for (;;)
{
snp = search_buffer(ctx, optimal_encode, emd);
if (snp == NULL)
{
fprintf(stderr, "error: search_buffer() returned NULL\n");
exit(-1);
}
float size = snp->total_score;
if (size >= old_size)
{
#if 0 /* RH */
search_node_free(snp);
#endif /* RH */
break;
}
#if 0 /* RH */
if (best_snp != NULL)
{
search_node_free(best_snp);
}
#endif /* RH */
best_snp = snp;
old_size = size;
++pass;
if (pass > max_passes)
{
break;
}
optimal_free(emd);
optimal_init(emd);
matchp_snp_get_enum(snp, snpe);
optimal_optimize(emd, matchp_snp_enum_get_next, snpe);
}
return best_snp;
}
