X-Git-Url: https://git.sesse.net/?p=fjl;a=blobdiff_plain;f=input.h;h=b57c814dfcefd0c8d1c68045fc7cc1a7513ea333;hp=34765c25b113b35efff8c77ccf4d3f3e09ae30f0;hb=85cda6b1da31916b0127d1217825dea725619245;hpb=71b4fae2b31acf415c3b07a019ae252f4d128952

diff --git a/input.h b/input.h
index 34765c2..b57c814 100644
--- a/input.h
+++ b/input.h
@@ -1,90 +1,21 @@
 #ifndef _INPUT_H
 #define _INPUT_H 1
 
-#include <assert.h>
-#include <stddef.h>
 #include <stdint.h>
 #include <sys/types.h>
-#include <arpa/inet.h>
-
-// Optimize for 64 bits. We might want to replace this for 32-bit machines
-// (benchmark later).
-typedef uint64_t bitreservoir_t;
-typedef uint32_t bitreservoir_fill_t;
-
-static inline bitreservoir_fill_t read_bitreservoir_fill(uint8_t* source)
-{
-	return ntohl(*(bitreservoir_fill_t*)(source));
-}
-
-static const unsigned bitreservoir_size = 8 * sizeof(bitreservoir_t);
-static const unsigned bitreservoir_fill_size = 8 * sizeof(bitreservoir_fill_t);
-static const unsigned bytereservoir_size = 4096;
 
 // A function to read bytes from some input source. The bytes should be
 // already unstuffed (and thus without markers).
 // A return value of -1 indicates error, a return value of 0 indicates EOF.
 typedef ssize_t (input_func_t)(void*, uint8_t*, size_t);
 
-// A data source for efficient reading of bit-level data.
-struct bit_source {
-	// Short-term bit reservoir; holds up to 64 bits. When it's empty,
-	// it needs to get refilled from the medium-term bit reservoir.
-	bitreservoir_t bits;
-	unsigned bits_available;
-	
-	// Medium-term bit reservoir; holds a few kilobytes of spare data.
-	// When this is empty, it needs to be refilled from the input
-	// stream.
-	uint8_t* bytes;
-	unsigned bytes_available;
-
-	// Data source.
-	input_func_t* input_func;
-	void* userdata;
-};
-
-void init_bit_source(struct bit_source* source, input_func_t* input_func, void* userdata);
-
-// Internal function. Do not use.
-void possibly_refill_slow_path(struct bit_source* source, unsigned num_bits);
-
-// Make sure there's at least NUM_BITS available in the short-term bit reservoir.
-// You usually want to call this before read_bits(). The reason it's separate
-// is that if you want two reads and you know the size of both, it's faster to
-// refill A+B, read A, read B than refill A, read A, refill B, read B.
-static inline void possibly_refill(struct bit_source* source, unsigned num_bits)
-{
-	assert(num_bits <= bitreservoir_fill_size + 1);
-
-	if (source->bits_available >= num_bits) {
-		// Fast path (~90% of invocations?)
-		return;
-	}
-
-	// Slower path (~99% of remaining invocations?)
-	assert(source->bits_available + bitreservoir_fill_size < bitreservoir_size);
-	if (source->bytes_available >= sizeof(bitreservoir_fill_t)) {
-		bitreservoir_fill_t fill = read_bitreservoir_fill(source->bytes);
-		source->bytes += sizeof(bitreservoir_fill_t);
-		source->bytes_available -= sizeof(bitreservoir_fill_t);
-		source->bits |= (bitreservoir_t)fill << (bitreservoir_size - bitreservoir_fill_size - source->bits_available);
-		source->bits_available += bitreservoir_fill_size;
-		return;
-	}
+// Same as input_func_t, although it expects raw bytes, ie. with markers
+// and all.
+typedef ssize_t (raw_input_func_t)(void*, uint8_t*, size_t);
 
-	// Slow path: Refill from data source.
-	// Should not be inlined, so split into a separate function.
-	possibly_refill_slow_path(source, num_bits);
-}
+void reliable_read(raw_input_func_t* input_func, void* userdata, uint8_t* buf, size_t len);
 
-static inline unsigned read_bits(struct bit_source* source, unsigned num_bits)
-{
-	assert(source->bits_available >= num_bits);
-	unsigned ret = (source->bits >> (bitreservoir_size - num_bits));
-	source->bits <<= num_bits;
-	source->bits_available -= num_bits;
-	return ret;
-}
+uint8_t read_uint8(raw_input_func_t* input_func, void* userdata);
+uint16_t read_uint16(raw_input_func_t* input_func, void* userdata);
 
 #endif /* !defined(_INPUT_H) */