mirror of
https://github.com/GerbilSoft/zlib-ng.git
synced 2025-06-18 11:35:35 -04:00
3eab3173ac
There is no hardware control for DFLTCC window size, and because of that supporting small windows for deflate is not trivial: one has to make sure that DFLTCC does not emit large distances, which most likely entails somehow trimming the window and/or input in order to make sure that whave + avail_in <= wsize. But inflate is much easier: one only has to allocate enough space. Do that in dfltcc_alloc_window(), and also introduce ZCOPY_WINDOW() in order to copy everything, not just what the software implementation cares about. After this change, software and hardware window formats no longer match: the software will use wbits and wsize, and the hardware will use HB_BITS and HB_SIZE. Unlike deflate, inflate does not switch between software and hardware implementations mid-stream, which leaves only inflateSetDictionary() and inflateGetDictionary() interesting.
68 lines
2.1 KiB
C++
68 lines
2.1 KiB
C++
/* test_small_window.cc - Test deflate() and inflate() with a small window and a preset dictionary */
|
|
|
|
#include "zbuild.h"
|
|
#ifdef ZLIB_COMPAT
|
|
# include "zlib.h"
|
|
#else
|
|
# include "zlib-ng.h"
|
|
#endif
|
|
|
|
#include <gtest/gtest.h>
|
|
|
|
TEST(small_window, basic) {
|
|
PREFIX3(stream) stream;
|
|
int err;
|
|
unsigned char plain[128];
|
|
unsigned char dictionary1[(1 << 9) - sizeof(plain) / 2];
|
|
size_t i;
|
|
unsigned char compr[sizeof(plain)];
|
|
unsigned int compr_len;
|
|
unsigned char plain_again[sizeof(plain)];
|
|
|
|
memset(&stream, 0, sizeof(stream));
|
|
err = PREFIX(deflateInit2)(&stream, Z_BEST_COMPRESSION, Z_DEFLATED, -9, 8, Z_DEFAULT_STRATEGY);
|
|
EXPECT_EQ(err, Z_OK);
|
|
|
|
/* Use a large dictionary that is loaded in two parts */
|
|
memset(dictionary1, 'a', sizeof(dictionary1));
|
|
err = PREFIX(deflateSetDictionary)(&stream, dictionary1, (unsigned int)sizeof(dictionary1));
|
|
EXPECT_EQ(err, Z_OK);
|
|
for (i = 0; i < sizeof(plain); i++)
|
|
plain[i] = (unsigned char)i;
|
|
err = PREFIX(deflateSetDictionary)(&stream, plain, (unsigned int)sizeof(plain));
|
|
EXPECT_EQ(err, Z_OK);
|
|
|
|
stream.next_in = plain;
|
|
stream.avail_in = (uint32_t)sizeof(plain);
|
|
stream.next_out = compr;
|
|
stream.avail_out = (uint32_t)sizeof(compr);
|
|
err = PREFIX(deflate)(&stream, Z_FINISH);
|
|
EXPECT_EQ(err, Z_STREAM_END);
|
|
compr_len = sizeof(compr) - stream.avail_out;
|
|
|
|
err = PREFIX(deflateEnd)(&stream);
|
|
EXPECT_EQ(err, Z_OK);
|
|
|
|
memset(&stream, 0, sizeof(stream));
|
|
err = PREFIX(inflateInit2)(&stream, -9);
|
|
EXPECT_EQ(err, Z_OK);
|
|
|
|
err = PREFIX(inflateSetDictionary)(&stream, dictionary1, (unsigned int)sizeof(dictionary1));
|
|
EXPECT_EQ(err, Z_OK);
|
|
err = PREFIX(inflateSetDictionary)(&stream, plain, (unsigned int)sizeof(plain));
|
|
EXPECT_EQ(err, Z_OK);
|
|
|
|
stream.next_in = compr;
|
|
stream.avail_in = compr_len;
|
|
stream.next_out = plain_again;
|
|
stream.avail_out = (unsigned int)sizeof(plain_again);
|
|
|
|
err = PREFIX(inflate)(&stream, Z_NO_FLUSH);
|
|
EXPECT_EQ(err, Z_STREAM_END);
|
|
|
|
err = PREFIX(inflateEnd)(&stream);
|
|
EXPECT_EQ(err, Z_OK);
|
|
|
|
EXPECT_TRUE(memcmp(plain_again, plain, sizeof(plain)) == 0);
|
|
}
|