Turn udeflate into a proper library

2 files changed, 10 insertions, 351 deletions

diff --git a/src/app/deflatetest/Makefile.inc b/src/app/deflatetest/Makefile.inc
index b8ed566..84a6aff 100644
--- a/src/app/deflatetest/Makefile.inc
+++ b/src/app/deflatetest/Makefile.inc
@@ -7,4 +7,7 @@
 ifdef app
 	override timer_s = 0
 	override loop = 0
+	override arch_drivers += ,counter
 endif
+
+CXX_TARGETS += src/lib/udeflate.cc
diff --git a/src/app/deflatetest/main.cc b/src/app/deflatetest/main.cc
index db8e4a5..516a6a0 100644
--- a/src/app/deflatetest/main.cc
+++ b/src/app/deflatetest/main.cc
@@ -7,6 +7,9 @@
 #include "driver/gpio.h"
 #include "driver/stdout.h"
 #include "driver/uptime.h"
+#include "driver/counter.h"
+
+#include "lib/udeflate.h"
 
 #define UDEFLATE_ERR_LENGTH (-1)
 #define UDEFLATE_ERR_METHOD (-2)
@@ -43,357 +46,7 @@ unsigned char const deflate_input[] = {
 };
 */
 
-
-unsigned char* udeflate_input_end;
-unsigned char* udeflate_input_now;
-uint8_t udeflate_bit_offset = 0;
-
 unsigned char deflate_output[1024];
-uint16_t deflate_output_pos;
-
-uint16_t const udeflate_length_offsets[] = {
-	3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 35, 43, 51, 59, 67,
-	83, 99, 115, 131, 163, 195, 227, 258
-};
-
-// TODO (index < 4 || index == 28) ? 0 : (index-4) >> 2
-uint8_t const udeflate_length_bits[] = {
-	0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5,
-	5, 5, 5, 0
-};
-
-uint16_t const udeflate_distance_offsets[] = {
-	1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385, 513,
-	769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577
-};
-
-// TODO index < 2 ? 0 : (index-2) >> 1
-uint8_t const udeflate_distance_bits[] = {
-	0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10,
-	11, 11, 12, 12, 13, 13
-};
-
-uint8_t const udeflate_hclen_index[] = {
-	16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15
-};
-
-uint8_t udeflate_hc_lengths[19];
-uint8_t udeflate_lld_lengths[318];
-
-static uint16_t udeflate_rev_word(uint16_t word, uint8_t bits)
-{
-	uint16_t ret = 0;
-	uint16_t mask = 1;
-	for (uint16_t rmask = 1 << (bits-1); rmask > 0; rmask >>= 1) {
-		if (word & rmask) {
-			ret |= mask;
-		}
-		mask <<= 1;
-	}
-	return ret;
-}
-
-static uint8_t udeflate_bitmask(uint8_t bit_count)
-{
-	return (1 << bit_count) - 1;
-}
-
-static uint16_t udeflate_get_word()
-{
-	uint16_t ret = 0;
-	ret |= (udeflate_input_now[0] >> udeflate_bit_offset);
-	ret |= (uint16_t)udeflate_input_now[1] << (8 - udeflate_bit_offset);
-	if (udeflate_bit_offset) {
-		ret |= (uint16_t)(udeflate_input_now[2] & udeflate_bitmask(udeflate_bit_offset)) << (16 - udeflate_bit_offset);
-	}
-#ifdef UDEFLATE_DEBUG
-	kout << "get_word = " << bin << ret << dec << endl;
-#endif
-	return ret;
-}
-
-static uint16_t udeflate_get_bits(uint8_t num_bits)
-{
-	uint16_t ret = udeflate_get_word();
-	udeflate_bit_offset += num_bits;
-	while (udeflate_bit_offset >= 8) {
-		udeflate_input_now++;
-		udeflate_bit_offset -= 8;
-	}
-	return ret & udeflate_bitmask(num_bits);
-}
-
-/*
- * Assumptions:
- * * huffman code length is limited to 11 bits
- * * there are no more than 255 huffman codes with the same length
- *
- * Rationale: longer huffman codes might appear when handling large data
- * sets. We don't do that; instead, we expect the uncompressed source to
- * be no more than a few kB of data.
- */
-
-// used for huffman alphabet in type 2 and literal/length alphabet in type 1&2
-uint8_t udeflate_bl_count_ll[12];
-uint16_t udeflate_next_code_ll[12];
-
-// used for distance alphabet in types 1&2
-uint8_t udeflate_bl_count_d[12];
-uint16_t udeflate_next_code_d[12];
-
-static void udeflate_build_alphabet(uint8_t* lengths, uint16_t size, uint8_t* bl_count, uint16_t* next_code)
-{
-	uint16_t i;
-	uint16_t code = 0;
-	uint16_t max_len = 0;
-	for (i = 0; i < 12; i++) {
-		bl_count[i] = 0;
-	}
-
-	for (i = 0; i < size; i++) {
-		if (lengths[i]) {
-			bl_count[lengths[i]]++;
-		}
-		if (lengths[i] > max_len) {
-			max_len = lengths[i];
-		}
-	}
-
-	for (i = 1; i < max_len+1; i++) {
-		code = (code + bl_count[i-1]) << 1;
-		next_code[i] = code;
-	}
-
-#ifdef UDEFLATE_DEBUG
-	for (i = 0; i < 12; i++) {
-		kout << "bl_count[" << i << "] = " << bl_count[i] << endl;
-	}
-	for (i = 0; i < 12; i++) {
-		kout << "next_code[" << i << "] = " << next_code[i] << endl;
-	}
-#endif
-}
-
-static uint16_t udeflate_huff(uint8_t* lengths, uint16_t size, uint8_t* bl_count, uint16_t* next_code)
-{
-	uint16_t next_word = udeflate_get_word();
-	for (uint8_t num_bits = 1; num_bits < 12; num_bits++) {
-		uint16_t next_bits = udeflate_rev_word(next_word, num_bits);
-		if (bl_count[num_bits] && next_bits >= next_code[num_bits] && next_bits < next_code[num_bits] + bl_count[num_bits] ) {
-#ifdef UDEFLATE_DEBUG
-			kout << "found huffman code, length = " << num_bits << endl;
-#endif
-			udeflate_bit_offset += num_bits;
-			while (udeflate_bit_offset >= 8) {
-				udeflate_input_now++;
-				udeflate_bit_offset -= 8;
-			}
-			uint8_t len_pos = next_bits;
-			uint8_t cur_pos = next_code[num_bits];
-			for (uint16_t i = 0; i < size; i++) {
-				if (lengths[i] == num_bits) {
-					if (cur_pos == len_pos) {
-						return i;
-					}
-					cur_pos++;
-				}
-			}
-		}
-	}
-	return 65535;
-}
-
-static int8_t udeflate_huffman(uint8_t* ll_lengths, uint16_t ll_size, uint8_t* d_lengths, uint8_t d_size)
-{
-	uint16_t code;
-	uint16_t dcode;
-	deflate_output_pos = 0;
-	while (1) {
-		code = udeflate_huff(ll_lengths, ll_size, udeflate_bl_count_ll, udeflate_next_code_ll);
-#ifdef UDEFLATE_DEBUG
-		kout << "code " << code << endl;
-#endif
-		if (code < 256) {
-			deflate_output[deflate_output_pos] = code;
-			deflate_output_pos++;
-		} else if (code == 256) {
-			return 0;
-		} else {
-			uint16_t len_val = udeflate_length_offsets[code - 257];
-			uint8_t extra_bits = udeflate_length_bits[code - 257];
-			if (extra_bits) {
-				len_val += udeflate_get_bits(extra_bits);
-			}
-			dcode = udeflate_huff(d_lengths, d_size, udeflate_bl_count_d, udeflate_next_code_d);
-			uint16_t dist_val = udeflate_distance_offsets[dcode];
-			extra_bits = udeflate_distance_bits[dcode];
-			if (extra_bits) {
-				dist_val += udeflate_get_bits(extra_bits);
-			}
-			while (len_val--) {
-				deflate_output[deflate_output_pos] = deflate_output[deflate_output_pos-dist_val];
-				deflate_output_pos++;
-			}
-		}
-	}
-}
-
-static int8_t udeflate_static_huffman()
-{
-	uint16_t i;
-	for (i = 0; i <= 143; i++) {
-		udeflate_lld_lengths[i] = 8;
-	}
-	for (i = 144; i <= 255; i++) {
-		udeflate_lld_lengths[i] = 9;
-	}
-	for (i = 256; i <= 279; i++) {
-		udeflate_lld_lengths[i] = 7;
-	}
-	for (i = 280; i <= 284; i++) {
-		udeflate_lld_lengths[i] = 8;
-	}
-	for (i = 285; i <= 285+29; i++) {
-		udeflate_lld_lengths[i] = 5;
-	}
-
-	udeflate_build_alphabet(udeflate_lld_lengths, 285, udeflate_bl_count_ll, udeflate_next_code_ll);
-	udeflate_build_alphabet(udeflate_lld_lengths + 285, 29, udeflate_bl_count_d, udeflate_next_code_d);
-	return udeflate_huffman(udeflate_lld_lengths, 285, udeflate_lld_lengths + 285, 29);
-}
-
-static int8_t udeflate_dynamic_huffman()
-{
-	uint8_t i;
-	uint16_t hlit = 257 + udeflate_get_bits(5);
-	uint8_t hdist = 1 + udeflate_get_bits(5);
-	uint8_t hclen = 4 + udeflate_get_bits(4);
-
-#ifdef UDEFLATE_DEBUG
-	kout << "hlit=" << hlit << endl;
-	kout << "hdist=" << hdist << endl;
-	kout << "hclen=" << hclen << endl;
-#endif
-
-	for (i = 0; i < hclen; i++) {
-		udeflate_hc_lengths[udeflate_hclen_index[i]] = udeflate_get_bits(3);
-	}
-	for (i = hclen; i < sizeof(udeflate_hc_lengths); i++) {
-		udeflate_hc_lengths[udeflate_hclen_index[i]] = 0;
-	}
-
-	udeflate_build_alphabet(udeflate_hc_lengths, sizeof(udeflate_hc_lengths), udeflate_bl_count_ll, udeflate_next_code_ll);
-
-	uint16_t items_processed = 0;
-	while (items_processed < hlit + hdist) {
-		uint8_t code = udeflate_huff(udeflate_hc_lengths, 19, udeflate_bl_count_ll, udeflate_next_code_ll);
-#ifdef UDEFLATE_DEBUG
-		kout << "code = " << code << endl;
-#endif
-		if (code == 16) {
-			uint8_t copy_count = 3 + udeflate_get_bits(2);
-			for (uint8_t i = 0; i < copy_count; i++) {
-				udeflate_lld_lengths[items_processed] = udeflate_lld_lengths[items_processed-1];
-				items_processed++;
-			}
-		}
-		else if (code == 17) {
-			uint8_t null_count = 3 + udeflate_get_bits(3);
-			for (uint8_t i = 0; i < null_count; i++) {
-				udeflate_lld_lengths[items_processed] = 0;
-				items_processed++;
-			}
-		}
-		else if (code == 18) {
-			uint8_t null_count = 11 + udeflate_get_bits(7);
-			for (uint8_t i = 0; i < null_count; i++) {
-				udeflate_lld_lengths[items_processed] = 0;
-				items_processed++;
-			}
-		}
-		else {
-			udeflate_lld_lengths[items_processed] = code;
-			items_processed++;
-		}
-	}
-
-	udeflate_build_alphabet(udeflate_lld_lengths, hlit, udeflate_bl_count_ll, udeflate_next_code_ll);
-	udeflate_build_alphabet(udeflate_lld_lengths + hlit, hdist, udeflate_bl_count_d, udeflate_next_code_d);
-
-	return udeflate_huffman(udeflate_lld_lengths, hlit, udeflate_lld_lengths + hlit, hdist);
-
-	return 0;
-}
-
-int8_t udeflate(unsigned char* buf, uint16_t buf_len)
-{
-	uint8_t is_final = buf[0] & 0x01;
-	uint8_t block_type = (buf[0] & 0x06) >> 1;
-#ifdef UDEFLATE_DEBUG
-	kout << "is_final=" << is_final << " block_type=" << block_type << endl;
-#endif
-
-	udeflate_input_now = buf;
-	udeflate_input_end = buf + buf_len;
-	udeflate_bit_offset = 3;
-
-	if (block_type == 1) {
-		return udeflate_static_huffman();
-	}
-	if (block_type == 2) {
-		return udeflate_dynamic_huffman();
-	}
-
-	return UDEFLATE_ERR_BLOCK;
-}
-
-int8_t udeflate_zlib(unsigned char* buf, uint16_t buf_len)
-{
-	if (buf_len < 4) {
-		return UDEFLATE_ERR_LENGTH;
-	}
-	uint8_t zlib_method = buf[0] & 0x0f;
-	uint16_t zlib_window_size = 1 << (8 + ((buf[0] & 0xf0) >> 4));
-	uint8_t zlib_flags = buf[1];
-
-#ifdef UDEFLATE_DEBUG
-	kout << "zlib_method=" << zlib_method << endl;
-	kout << "zlib_window_size=" << zlib_window_size << endl;
-#endif
-
-	if (zlib_method != 8) {
-		return UDEFLATE_ERR_METHOD;
-	}
-
-	if (zlib_flags & 0x10) {
-		return UDEFLATE_ERR_FDICT;
-	}
-
-	uint8_t ret = udeflate(buf+2, buf_len-2);
-
-#ifdef UDEFLATE_CHECKSUM
-	if (ret == 0) {
-		uint16_t udeflate_s1 = 1;
-		uint16_t udeflate_s2 = 0;
-
-		for (uint16_t i = 0; i < deflate_output_pos; i++) {
-			udeflate_s1 = ((uint32_t)udeflate_s1 + (uint32_t)deflate_output[i]) % 65521;
-			udeflate_s2 = ((uint32_t)udeflate_s2 + (uint32_t)udeflate_s1) % 65521;
-		}
-
-		if (udeflate_bit_offset) {
-			udeflate_input_now++;
-		}
-
-		if ((udeflate_s2 != (((uint16_t)udeflate_input_now[0] << 8) | (uint16_t)udeflate_input_now[1]))
-				|| (udeflate_s1 != (((uint16_t)udeflate_input_now[2] << 8) | (uint16_t)udeflate_input_now[3]))) {
-			return UDEFLATE_ERR_CHECKSUM;
-		}
-	}
-#endif
-
-	return ret;
-}
 
 int main(void)
 {
@@ -402,9 +55,12 @@ int main(void)
 	kout.setup();
 
 	for (uint8_t i = 0; i < 5; i++) {
-		int8_t ret = udeflate_zlib((unsigned char*)deflate_input, sizeof(deflate_input));
+		counter.start();
+		int8_t ret = udeflate_zlib((unsigned char*)deflate_input, sizeof(deflate_input), deflate_output, sizeof(deflate_output));
+		counter.stop();
 		kout << "udeflate returned " << ret << endl;
 		kout << "Output: " << (char*)deflate_output << endl;
+		kout << "took " << counter.value << "/" << counter.overflow << " cycles" << endl;
 	}
 
 	arch.idle();