| /* |
| * Copyright 2008, 2009, 2014 Free Software Foundation, Inc. |
| * Copyright 2014 Range Networks, Inc. |
| * |
| * This program is free software: you can redistribute it and/or modify |
| * it under the terms of the GNU Affero General Public License as published by |
| * the Free Software Foundation, either version 3 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU Affero General Public License for more details. |
| * |
| * You should have received a copy of the GNU Affero General Public License |
| * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| * |
| * This use of this software may be subject to additional restrictions. |
| * See the LEGAL file in the main directory for details. |
| */ |
| |
| #ifndef BITVECTORS_H |
| #define BITVECTORS_H |
| |
| #include "Vector.h" |
| #include <stdint.h> |
| #include <stdio.h> |
| |
| |
| class BitVector; |
| class SoftVector; |
| |
| |
| |
| |
| /** Shift-register (LFSR) generator. */ |
| class Generator { |
| |
| private: |
| |
| uint64_t mCoeff; ///< polynomial coefficients. LSB is zero exponent. |
| uint64_t mState; ///< shift register state. LSB is most recent. |
| uint64_t mMask; ///< mask for reading state |
| unsigned mLen; ///< number of bits used in shift register |
| unsigned mLen_1; ///< mLen - 1 |
| |
| public: |
| |
| Generator(uint64_t wCoeff, unsigned wLen) |
| :mCoeff(wCoeff),mState(0), |
| mMask((1ULL<<wLen)-1), |
| mLen(wLen),mLen_1(wLen-1) |
| { assert(wLen<64); } |
| |
| void clear() { mState=0; } |
| |
| /**@name Accessors */ |
| //@{ |
| uint64_t state() const { return mState & mMask; } |
| unsigned size() const { return mLen; } |
| //@} |
| |
| /** |
| Calculate one bit of a syndrome. |
| This is in the .h for inlining. |
| */ |
| void syndromeShift(unsigned inBit) |
| { |
| const unsigned fb = (mState>>(mLen_1)) & 0x01; |
| mState = (mState<<1) ^ (inBit & 0x01); |
| if (fb) mState ^= mCoeff; |
| } |
| |
| /** |
| Update the generator state by one cycle. |
| This is in the .h for inlining. |
| */ |
| void encoderShift(unsigned inBit) |
| { |
| const unsigned fb = ((mState>>(mLen_1)) ^ inBit) & 0x01; |
| mState <<= 1; |
| if (fb) mState ^= mCoeff; |
| } |
| |
| |
| }; |
| |
| |
| |
| |
| /** Parity (CRC-type) generator and checker based on a Generator. */ |
| class Parity : public Generator { |
| |
| protected: |
| |
| unsigned mCodewordSize; |
| |
| public: |
| |
| Parity(uint64_t wCoefficients, unsigned wParitySize, unsigned wCodewordSize) |
| :Generator(wCoefficients, wParitySize), |
| mCodewordSize(wCodewordSize) |
| { } |
| |
| /** Compute the parity word and write it into the target segment. */ |
| void writeParityWord(const BitVector& data, BitVector& parityWordTarget, bool invert=true); |
| |
| /** Compute the syndrome of a received sequence. */ |
| uint64_t syndrome(const BitVector& receivedCodeword); |
| }; |
| |
| |
| // (pat) Nov 2013. I rationalized the behavior of BitVector and added assertions to core dump code |
| // that relied on the bad aspects of the original behavior. See comments at VectorBase. |
| class BitVector : public VectorBase<char> |
| { |
| public: |
| /**@name Constructors. */ |
| //@{ |
| |
| /**@name Casts of Vector constructors. */ |
| BitVector(VectorDataType wData, char* wStart, char* wEnd) : VectorBase<char>(wData, wStart, wEnd) {} |
| |
| // The one and only copy-constructor. |
| BitVector(const BitVector&other) : VectorBase<char>() { |
| VECTORDEBUG("BitVector(%p)",(void*)&other); |
| if (other.getData()) { |
| this->clone(other); |
| } else { |
| this->makeAlias(other); |
| } |
| } |
| |
| // (pat) Removed default value for len and added 'explicit'. Please do not remove 'explicit'; |
| // it prevents auto-conversion of int to BitVector in constructors. |
| // Previous code was often ambiguous, especially for L3Frame and descendent constructors, leading to latent bugs. |
| explicit BitVector(size_t len) { this->vInit(len); } |
| BitVector() { this->vInit(0); } |
| |
| /** Build a BitVector by concatenation. */ |
| BitVector(const BitVector& other1, const BitVector& other2) : VectorBase<char>() |
| { |
| assert(this->getData() == 0); |
| this->vConcat(other1,other2); |
| } |
| |
| /** Construct from a string of "0" and "1". */ |
| // (pat) Characters that are not '0' or '1' map to '0'. |
| BitVector(const char* valString); |
| //@} |
| |
| /**@name Casts and overrides of Vector operators. */ |
| //@{ |
| // (pat) Please DO NOT add a const anywhere in this method. Use cloneSegment instead. |
| BitVector segment(size_t start, size_t span) |
| { |
| char* wStart = this->begin() + start; |
| char* wEnd = wStart + span; |
| assert(wEnd<=this->end()); |
| #if BITVECTOR_REFCNTS |
| return BitVector(mData,wStart,wEnd); |
| #else |
| return BitVector(NULL,wStart,wEnd); |
| #endif |
| } |
| |
| // (pat) Historically the BitVector segment method had const and non-const versions with different behavior. |
| // I changed the name of the const version to cloneSegment and replaced all uses throughout OpenBTS. |
| const BitVector cloneSegment(size_t start, size_t span) const |
| { |
| BitVector seg = const_cast<BitVector*>(this)->segment(start,span); |
| // (pat) We are depending on the Return Value Optimization not to invoke the copy-constructor on the result, |
| // which would result in its immediate destruction while we are still using it. |
| BitVector result; |
| result.clone(seg); |
| return result; |
| } |
| |
| BitVector alias() const { |
| return const_cast<BitVector*>(this)->segment(0,size()); |
| } |
| |
| BitVector head(size_t span) { return segment(0,span); } |
| BitVector tail(size_t start) { return segment(start,size()-start); } |
| |
| // (pat) Please do NOT put the const version of head and tail back in, because historically they were messed up. |
| // Use cloneSegment instead. |
| //const BitVector head(size_t span) const { return segment(0,span); } |
| //const BitVector tail(size_t start) const { return segment(start,size()-start); } |
| //@} |
| |
| |
| void zero() { fill(0); } |
| |
| /**@name FEC operations. */ |
| //@{ |
| /** Calculate the syndrome of the vector with the given Generator. */ |
| uint64_t syndrome(Generator& gen) const; |
| /** Calculate the parity word for the vector with the given Generator. */ |
| uint64_t parity(Generator& gen) const; |
| //@} |
| |
| |
| /** Invert 0<->1. */ |
| void invert(); |
| |
| /**@name Byte-wise operations. */ |
| //@{ |
| /** Reverse an 8-bit vector. */ |
| void reverse8(); |
| /** Reverse groups of 8 within the vector (byte reversal). */ |
| void LSB8MSB(); |
| //@} |
| |
| /**@name Serialization and deserialization. */ |
| //@{ |
| uint64_t peekField(size_t readIndex, unsigned length) const; |
| uint64_t peekFieldReversed(size_t readIndex, unsigned length) const; |
| uint64_t readField(size_t& readIndex, unsigned length) const; |
| uint64_t readFieldReversed(size_t& readIndex, unsigned length) const; |
| void fillField(size_t writeIndex, uint64_t value, unsigned length); |
| void fillFieldReversed(size_t writeIndex, uint64_t value, unsigned length); |
| void writeField(size_t& writeIndex, uint64_t value, unsigned length); |
| void writeFieldReversed(size_t& writeIndex, uint64_t value, unsigned length); |
| void write0(size_t& writeIndex) { writeField(writeIndex,0,1); } |
| void write1(size_t& writeIndex) { writeField(writeIndex,1,1); } |
| |
| //@} |
| |
| /** Sum of bits. */ |
| unsigned sum() const; |
| |
| /** Reorder bits, dest[i] = this[map[i]]. */ |
| void map(const unsigned *map, size_t mapSize, BitVector& dest) const; |
| |
| /** Reorder bits, dest[map[i]] = this[i]. */ |
| void unmap(const unsigned *map, size_t mapSize, BitVector& dest) const; |
| |
| /** Pack into a char array. */ |
| void pack(unsigned char*) const; |
| |
| /* Roman: This is here for debugging */ |
| void pack2(unsigned char*) const; |
| |
| // Same as pack but return a string. |
| std::string packToString() const; |
| |
| /** Unpack from a char array. */ |
| void unpack(const unsigned char*); |
| |
| /** Make a hexdump string. */ |
| void hex(std::ostream&) const; |
| std::string hexstr() const; |
| |
| /** Unpack from a hexdump string. |
| * @returns true on success, false on error. */ |
| bool unhex(const char*); |
| |
| // For this method, 'other' should have been run through the copy-constructor already |
| // (unless it was newly created, ie foo.dup(L2Frame(...)), in which case we are screwed anyway) |
| // so the call to makeAlias is redundant. |
| // This only works if other is already an alias. |
| void dup(BitVector other) { assert(!this->getData()); makeAlias(other); assert(this->mStart == other.mStart); } |
| void dup(BitVector &other) { makeAlias(other); assert(this->mStart == other.mStart); } |
| |
| #if 0 |
| void operator=(const BitVector& other) { |
| printf("BitVector::operator=\n"); |
| assert(0); |
| //this->dup(other); |
| } |
| #endif |
| |
| bool operator==(const BitVector &other) const; |
| |
| /** Copy to dst, not including those indexed in puncture. */ |
| void copyPunctured(BitVector &dst, const unsigned *puncture, const size_t plth); |
| |
| /** Index a single bit. */ |
| // (pat) Cant have too many ways to do this, I guess. |
| bool bit(size_t index) const |
| { |
| // We put this code in .h for fast inlining. |
| const char *dp = this->begin()+index; |
| assert(dp<this->end()); |
| return (*dp) & 0x01; |
| } |
| |
| char& operator[](size_t index) |
| { |
| assert(this->mStart+index<this->mEnd); |
| return this->mStart[index]; |
| } |
| |
| const char& operator[](size_t index) const |
| { |
| assert(this->mStart+index<this->mEnd); |
| return this->mStart[index]; |
| } |
| |
| /** Set a bit */ |
| void settfb(size_t index, int value) |
| { |
| char *dp = this->mStart+index; |
| assert(dp<this->mEnd); |
| *dp = value; |
| } |
| |
| typedef char* iterator; |
| typedef const char* const_iterator; |
| }; |
| |
| // (pat) BitVector2 was an intermediate step in fixing BitVector but is no longer needed. |
| #define BitVector2 BitVector |
| |
| |
| std::ostream& operator<<(std::ostream&, const BitVector&); |
| |
| |
| |
| |
| |
| |
| /** |
| The SoftVector class is used to represent a soft-decision signal. |
| Values 0..1 represent probabilities that a bit is "true". |
| */ |
| class SoftVector: public Vector<float> { |
| |
| public: |
| |
| /** Build a SoftVector of a given length. */ |
| SoftVector(size_t wSize=0):Vector<float>(wSize) {} |
| |
| /** Construct a SoftVector from a C string of "0", "1", and "X". */ |
| SoftVector(const char* valString); |
| |
| /** Construct a SoftVector from a BitVector. */ |
| SoftVector(const BitVector& source); |
| |
| /** |
| Wrap a SoftVector around a block of floats. |
| The block will be delete[]ed upon desctuction. |
| */ |
| SoftVector(float *wData, unsigned length) |
| :Vector<float>(wData,length) |
| {} |
| |
| SoftVector(float* wData, float* wStart, float* wEnd) |
| :Vector<float>(wData,wStart,wEnd) |
| { } |
| |
| /** |
| Casting from a Vector<float>. |
| Note that this is NOT pass-by-reference. |
| */ |
| SoftVector(Vector<float> source) |
| :Vector<float>(source) |
| {} |
| |
| |
| /**@name Casts and overrides of Vector operators. */ |
| //@{ |
| SoftVector segment(size_t start, size_t span) |
| { |
| float* wStart = mStart + start; |
| float* wEnd = wStart + span; |
| assert(wEnd<=mEnd); |
| return SoftVector(NULL,wStart,wEnd); |
| } |
| |
| SoftVector alias() |
| { return segment(0,size()); } |
| |
| const SoftVector segment(size_t start, size_t span) const |
| { return (SoftVector)(Vector<float>::segment(start,span)); } |
| |
| SoftVector head(size_t span) { return segment(0,span); } |
| const SoftVector head(size_t span) const { return segment(0,span); } |
| SoftVector tail(size_t start) { return segment(start,size()-start); } |
| const SoftVector tail(size_t start) const { return segment(start,size()-start); } |
| //@} |
| |
| // (pat) How good is the SoftVector in the sense of the bits being solid? |
| // Result of 1 is perfect and 0 means all the bits were 0.5 |
| // If plow is non-NULL, also return the lowest energy bit. |
| float getEnergy(float *low=0) const; |
| float getSNR() const; |
| |
| /** Fill with "unknown" values. */ |
| void unknown() { fill(0.5F); } |
| |
| /** Return a hard bit value from a given index by slicing. */ |
| bool bit(size_t index) const |
| { |
| const float *dp = mStart+index; |
| assert(dp<mEnd); |
| return (*dp)>0.5F; |
| } |
| |
| /** Slice the whole signal into bits. */ |
| BitVector sliced() const; |
| |
| /** Copy to dst, adding in 0.5 for those indexed in puncture. */ |
| void copyUnPunctured(SoftVector &dst, const unsigned *puncture, const size_t plth); |
| |
| /** Return a soft bit. */ |
| float softbit(size_t index) const |
| { |
| const float *dp = mStart+index; |
| assert(dp<mEnd); |
| return *dp; |
| } |
| |
| /** Set a soft bit */ |
| void settfb(size_t index, float value) |
| { |
| float *dp = mStart+index; |
| assert(dp<mEnd); |
| *dp = value; |
| } |
| }; |
| |
| |
| |
| std::ostream& operator<<(std::ostream&, const SoftVector&); |
| |
| |
| |
| |
| #endif |
| // vim: ts=4 sw=4 |