diff options
Diffstat (limited to 'src/bitstring.h')
-rw-r--r-- | src/bitstring.h | 197 |
1 files changed, 106 insertions, 91 deletions
diff --git a/src/bitstring.h b/src/bitstring.h index 8052691..f124d2d 100644 --- a/src/bitstring.h +++ b/src/bitstring.h | |||
@@ -1,6 +1,8 @@ | |||
1 | #ifndef BU_BITSTRING_H | 1 | #ifndef BU_BITSTRING_H |
2 | #define BU_BITSTRING_H | 2 | #define BU_BITSTRING_H |
3 | 3 | ||
4 | #include "bu/util.h" | ||
5 | |||
4 | namespace Bu | 6 | namespace Bu |
5 | { | 7 | { |
6 | /** | 8 | /** |
@@ -18,32 +20,32 @@ namespace Bu | |||
18 | { | 20 | { |
19 | public: | 21 | public: |
20 | /** | 22 | /** |
21 | * Constructs a blank and basic BitString. This is actually useful since | 23 | * Constructs a blank and basic BitString. This is actually useful |
22 | * you can resize BitStrings at will, and even retain the data that was | 24 | * since you can resize BitStrings at will, and even retain the data |
23 | * in them. | 25 | * that was in them. |
24 | */ | 26 | */ |
25 | BitString(); | 27 | BitString(); |
26 | 28 | ||
27 | /** | 29 | /** |
28 | * Constructs a BitString object as a copy of another BitString. This is | 30 | * Constructs a BitString object as a copy of another BitString. This |
29 | * a standard copy constructor and produces an exact duplicate of the | 31 | * is a standard copy constructor and produces an exact duplicate of |
30 | * original BitString object. | 32 | * the original BitString object. |
31 | *@param xSrc Source BitString to copy data from. | 33 | *@param xSrc Source BitString to copy data from. |
32 | */ | 34 | */ |
33 | BitString( const BitString &xSrc ); | 35 | BitString( const BitString &xSrc ); |
34 | 36 | ||
35 | /** | 37 | /** |
36 | * Constructs a BitString with length nBits and optionally fills it with | 38 | * Constructs a BitString with length iBits and optionally fills it with |
37 | * random data. The default setting, to not fill randomly, will produce | 39 | * random data. The default setting, to not fill randomly, will produce |
38 | * a blank (all zeros) string of the specified size. | 40 | * a blank (all zeros) string of the specified size. |
39 | *@param nBits The length of the new BitString in bits. | 41 | *@param iBits The length of the new BitString in bits. |
40 | *@param bFillRandomly Wether or not to randomize this BitString. | 42 | *@param bFillRandomly Wether or not to randomize this BitString. |
41 | */ | 43 | */ |
42 | BitString( long nBits, bool bFillRandomly=false ); | 44 | BitString( long iBits, bool bFillRandomly=false ); |
43 | 45 | ||
44 | /** | 46 | /** |
45 | * Virtual deconstructor for the BitString. Takes care of cleanup for you. | 47 | * Virtual deconstructor for the BitString. Takes care of cleanup for |
46 | * What more do you really want to know? | 48 | * you. What more do you really want to know? |
47 | */ | 49 | */ |
48 | virtual ~BitString(); | 50 | virtual ~BitString(); |
49 | 51 | ||
@@ -52,86 +54,94 @@ namespace Bu | |||
52 | * Sets a bit in the BitString. In it's normal mode it will always turn | 54 | * Sets a bit in the BitString. In it's normal mode it will always turn |
53 | * the given bit on, to clear a bit set bBitState to false instead of | 55 | * the given bit on, to clear a bit set bBitState to false instead of |
54 | * true. This operation runs in O(1). | 56 | * true. This operation runs in O(1). |
55 | *@param nBit The zero-based index of the bit to modify. | 57 | *@param iBit The zero-based index of the bit to modify. |
56 | *@param bBitState Set to true to set the bit to 1, set to false to set | 58 | *@param bBitState Set to true to set the bit to 1, set to false to set |
57 | * the bit to 0. | 59 | * the bit to 0. |
58 | */ | 60 | */ |
59 | void setBit( long nBit, bool bBitState=true ); | 61 | void setBit( long iBit, bool bBitState=true ); |
60 | 62 | ||
61 | /** | 63 | /** |
62 | * Reverses the state of the given bit. This will set the given bit to a | 64 | * Reverses the state of the given bit. This will set the given bit |
63 | * 1 if it was 0, and to 0 if it was 1. This operation runs in O(1), and | 65 | * to a 1 if it was 0, and to 0 if it was 1. This operation runs in |
64 | * it should be noted that using this is marginally faster than doing the | 66 | * O(1), and it should be noted that using this is marginally faster |
65 | * test and flip yourself with getBit and setBit since it uses a bitwise | 67 | * than doing the test and flip yourself with getBit and setBit since |
66 | * not operation and doesn't actually test the bit itself. | 68 | * it uses a bitwise not operation and doesn't actually test the bit |
67 | *@param nBit The index of the bit to flip. | 69 | * itself. |
70 | *@param iBit The index of the bit to flip. | ||
68 | */ | 71 | */ |
69 | void flipBit( long nBit ); | 72 | void flipBit( long iBit ); |
70 | 73 | ||
71 | /** | 74 | /** |
72 | * Gets the state of the given bit. This follows the standard convention | 75 | * Gets the state of the given bit. This follows the standard |
73 | * used so far, a returned value of true means the bit in question is 1, | 76 | * convention used so far, a returned value of true means the bit in |
74 | * and a value of flase means the bit is 0. All bits out of range of the | 77 | * question is 1, and a value of flase means the bit is 0. All bits |
75 | * BitString are treated as off, but are "accessable" in that this does not | 78 | * out of range of the BitString are treated as off, but are |
76 | * produce any kind of error message. This is intentional. This operation | 79 | * "accessable" in that this does not produce any kind of error |
77 | * runs in O(1). | 80 | * message. This is intentional. This operation runs in O(1). |
78 | *@param nBit The index of the bit to test. | 81 | *@param iBit The index of the bit to test. |
79 | *@returns True for a 1, false for a 0. | 82 | *@returns True for a 1, false for a 0. |
80 | */ | 83 | */ |
81 | bool getBit( long nBit ); | 84 | bool getBit( long iBit ); |
82 | 85 | ||
83 | /** | 86 | /** |
84 | * Inverts the entire BitString, in effect this calls flipBit on every bit | 87 | * Inverts the entire BitString, in effect this calls flipBit on every |
85 | * in the string but is faster since it can operate on whole bytes at a | 88 | * bit in the string but is faster since it can operate on whole bytes |
86 | * time instead of individual bits. This operation runs in O(N). | 89 | * at a time instead of individual bits. This operation runs in O(N). |
87 | */ | 90 | */ |
88 | void invert(); | 91 | void invert(); |
89 | 92 | ||
90 | /** | 93 | /** |
91 | * Returns the number of bits allocated in this BitString. This operation | 94 | * Returns the number of bits allocated in this BitString. This |
92 | * runs in O(N) time since this value is cached and not computed. | 95 | * operation runs in O(1) time since this value is cached and not |
96 | * computed. | ||
93 | *@returns The number of bits allocated in this BitString. | 97 | *@returns The number of bits allocated in this BitString. |
94 | */ | 98 | */ |
99 | DEPRECATED | ||
95 | long getBitLength(); | 100 | long getBitLength(); |
96 | 101 | ||
102 | long getSize(); | ||
103 | |||
97 | /** | 104 | /** |
98 | * Sets the entire BitString to zeros, but it does it very quickly. This | 105 | * Sets the entire BitString to zeros, but it does it very quickly. |
99 | * operation runs in O(N). | 106 | * This operation runs in O(N). |
100 | */ | 107 | */ |
101 | void clearString(); | 108 | void clear(); |
102 | 109 | ||
103 | /** | 110 | /** |
104 | * Gets another BitString that is autonomous of the current one (contains | 111 | * Gets another BitString that is autonomous of the current one |
105 | * a copy of the memory, not a pointer) and contains a subset of the data | 112 | * (contains a copy of the memory, not a pointer) and contains a subset |
106 | * in the current BitString. This is an inclusive operation, so grabbing | 113 | * of the data in the current BitString. This is an inclusive |
107 | * bits 0-5 will give you 6 bits. This is based on a very tricky | 114 | * operation, so grabbing bits 0-5 will give you 6 bits. This is based |
108 | * bit-shifting algorithm and runs very quickly, in O(N) time. | 115 | * on a very tricky bit-shifting algorithm and runs very quickly, in |
109 | * Passing in a value of zero for nUpper, or any value for nUpper that is | 116 | * O(N) time. Passing in a value of zero for iUpper, or any value for |
110 | * less than nLower will set nUpper equal to the number of bits in the | 117 | * iUpper that is less than iLower will set iUpper equal to the number |
111 | * BitString. | 118 | * of bits in the BitString. |
112 | *@param nLower The first bit in the current string, will be the first bit | 119 | *@param iLower The first bit in the current string, will be the first |
113 | * (0 index) in the new sub string. | 120 | * bit (0 index) in the new sub string. |
114 | *@param nUpper The last bit in the current string, will be the last bit in | 121 | *@param iUpper The last bit in the current string, will be the last |
115 | * the new sub string. nUpper is included in the sub string. | 122 | * bit in the new sub string. iUpper is included in the sub string. |
116 | *@returns A new BitString object ready to be used. Please note that | 123 | *@returns A new BitString object ready to be used. Please note that |
117 | * managing this new object is up to whomever calls this function. | 124 | * managing this new object is up to whomever calls this function. |
118 | */ | 125 | */ |
119 | class BitString getSubString( long nLower, long nUpper ); | 126 | class BitString getSubString( long iLower, long iUpper ); |
120 | 127 | ||
121 | /** | 128 | /** |
122 | * Sets the number of bits in the BitString, allocating more memory if | 129 | * Sets the number of bits in the BitString, allocating more memory if |
123 | * necesarry, or freeing extra if able. The default operation of this | 130 | * necesarry, or freeing extra if able. The default operation of this |
124 | * function clears all data in the BitString while resizing it. If you | 131 | * function clears all data in the BitString while resizing it. If you |
125 | * would like to keep as much of the data that you had in your BitString | 132 | * would like to keep as much of the data that you had in your BitString |
126 | * as possible, then set bClear to false, and any data that will fit into | 133 | * as possible, then set bClear to false, and any data that will fit |
127 | * the new BitString length will be retained. If increasing the number of | 134 | * into the new BitString length will be retained. If increasing the |
128 | * bits, the new bits will come into existance cleared (set to 0). | 135 | * number of bits, the new bits will come into existance cleared (set |
129 | *@param nLength The number of bits to set the BitString to. | 136 | * to 0). |
130 | *@param bClear When true, all data is eradicated and zeroed, when set to | 137 | *@param iLength The number of bits to set the BitString to. |
131 | * false an effort is made to retain the existing data. | 138 | *@param bClear When true, all data is eradicated and zeroed, when set |
139 | * to false an effort is made to retain the existing data. | ||
132 | *@returns true on success, false on failure. | 140 | *@returns true on success, false on failure. |
133 | */ | 141 | */ |
134 | bool setBitLength( long nLength, bool bClear=true ); | 142 | DEPRECATED |
143 | bool setBitLength( long iLength, bool bClear=true ); | ||
144 | bool setSize( long iLength, bool bClear=true ); | ||
135 | 145 | ||
136 | /** | 146 | /** |
137 | * Randomize the entire BitString, one bit at a time. This is actually | 147 | * Randomize the entire BitString, one bit at a time. This is actually |
@@ -145,55 +155,57 @@ namespace Bu | |||
145 | * Operates exactly like <<. All data in the BitString is shifted to | 155 | * Operates exactly like <<. All data in the BitString is shifted to |
146 | * the left by some number of bits, any data pushed off the edge of the | 156 | * the left by some number of bits, any data pushed off the edge of the |
147 | * BitString is lost, and all new data coming in will be zeroed. | 157 | * BitString is lost, and all new data coming in will be zeroed. |
148 | * Using a negative value in the shiftLeft function will turn it into the | 158 | * Using a negative value in the shiftLeft function will turn it into |
149 | * shiftRight function. | 159 | * the shiftRight function. |
150 | *@param nAmt The number of bit positions to shift all data. | 160 | *@param iAmt The number of bit positions to shift all data. |
151 | */ | 161 | */ |
152 | void shiftLeft( long nAmt ); // just like << | 162 | void shiftLeft( long iAmt ); // just like << |
153 | 163 | ||
154 | /** | 164 | /** |
155 | * Operates exactly like >>. All data in the BitString is shifted to | 165 | * Operates exactly like >>. All data in the BitString is shifted to |
156 | * the right by some number of bits, any data pushed off the edge of the | 166 | * the right by some number of bits, any data pushed off the edge of the |
157 | * BitString is lost, and all new data coming in will be zeroed. | 167 | * BitString is lost, and all new data coming in will be zeroed. |
158 | * Using a negative value in the shiftRight function will turn it into the | 168 | * Using a negative value in the shiftRight function will turn it into |
159 | * shiftLeft function. | 169 | * the shiftLeft function. |
160 | *@param nAmt The number of bit positions to shift all data. | 170 | *@param iAmt The number of bit positions to shift all data. |
161 | */ | 171 | */ |
162 | void shiftRight( long nAmt ); // just like >> | 172 | void shiftRight( long iAmt ); // just like >> |
163 | 173 | ||
164 | /** | 174 | /** |
165 | * Searches through the BitString and returns the index of the highest | 175 | * Searches through the BitString and returns the index of the highest |
166 | * order bit position (the highest index) with an on bit (a bit set to 1). | 176 | * order bit position (the highest index) with an on bit (a bit set to |
167 | * This is a handy helper function and rather faster than calling getBit() | 177 | * 1). This is a handy helper function and rather faster than calling |
168 | * over and over again. | 178 | * getBit() over and over again. |
169 | *@returns The index of the highest indexed on bit. | 179 | *@returns The index of the highest indexed on bit. |
170 | */ | 180 | */ |
171 | long getHighestOrderBitPos(); | 181 | long getHighestOrderBitPos(); |
172 | 182 | ||
173 | // Conversion | 183 | // Conversion |
174 | /** | 184 | /** |
175 | * Convert a block of data (no more than 32 bits) to a primitive long type. | 185 | * Convert a block of data (no more than 32 bits) to a primitive long |
186 | * type. | ||
176 | * This is done in a little bit interesting way, so it may not always be | 187 | * This is done in a little bit interesting way, so it may not always be |
177 | * the fastest way to access the data that you want, although it will | 188 | * the fastest way to access the data that you want, although it will |
178 | * always ensure that the long that is written makes numerical sense, as | 189 | * always ensure that the long that is written makes numerical sense, as |
179 | * we write numbers, regaurdless of platform. | 190 | * we write numbers, regaurdless of platform. |
180 | *@param nStart The first bit in the BitString to include in the long | 191 | *@param iStart The first bit in the BitString to include in the long |
181 | *@param nSize THe number of bits to include, if this value is set over | 192 | *@param iSize THe number of bits to include, if this value is set over |
182 | * 32 it will be automatically truncated to, or however many bits there | 193 | * 32 it will be automatically truncated to, or however many bits there |
183 | * are in a long in your system. | 194 | * are in a long in your system. |
184 | *@returns A long converted from your raw BitString data. | 195 | *@returns A long converted from your raw BitString data. |
185 | */ | 196 | */ |
186 | long toLong( long nStart = 0, long nSize = 32 ); | 197 | long toLong( long iStart = 0, long iSize = 32 ); |
187 | 198 | ||
188 | /** | 199 | /** |
189 | * Converts the data into a human-readable SString object. SString is | 200 | * Converts the data into a human-readable SString object. SString is |
190 | * used to make transport of the string and management very simple. Since | 201 | * used to make transport of the string and management very simple. |
191 | * BitStrings will generally be longer than your average strip of ints a | 202 | * Since BitStrings will generally be longer than your average strip of |
192 | * faculty is included and turned on by default that will insert spacers | 203 | * ints a faculty is included and turned on by default that will insert |
193 | * into the output text every 8 places. For debugging work, this is | 204 | * spacers into the output text every 8 places. For debugging work, |
194 | * definately reccomended. | 205 | * this is definately reccomended. |
195 | *@param bAddSpacers Leave set to true in order to have the output broken | 206 | *@param bAddSpacers Leave set to true in order to have the output |
196 | * into logical groupings of 8 bits per block. Set to off to have a harder | 207 | * broken into logical groupings of 8 bits per block. Set to off to |
208 | * have a harder | ||
197 | * to read solid block of bits. | 209 | * to read solid block of bits. |
198 | *@returns A SString object containing the produced string. | 210 | *@returns A SString object containing the produced string. |
199 | */ | 211 | */ |
@@ -202,24 +214,25 @@ namespace Bu | |||
202 | // Utility | 214 | // Utility |
203 | /** | 215 | /** |
204 | * Converts the given number of bits into the smallest allocatable unit, | 216 | * Converts the given number of bits into the smallest allocatable unit, |
205 | * which is bytes in C and on most systems nowadays. This is the minimum | 217 | * which is bytes in C and on most systems nowadays. This is the |
206 | * number of bytes needed to contain the given number of bits, so there is | 218 | * minimum number of bytes needed to contain the given number of bits, |
207 | * generally some slop if they are not evenly divisible. | 219 | * so there is generally some slop if they are not evenly divisible. |
208 | *@param nBits The number of bits you wish to use. | 220 | *@param iBits The number of bits you wish to use. |
209 | *@returns The number of bytes you will need to contain the given number | 221 | *@returns The number of bytes you will need to contain the given number |
210 | * of bits. | 222 | * of bits. |
211 | */ | 223 | */ |
212 | //static long bitsToBytes( long nBits ); | 224 | //static long bitsToBytes( long iBits ); |
213 | 225 | ||
214 | /** | 226 | /** |
215 | * Writes all data in the BitString, including a small header block | 227 | * Writes all data in the BitString, including a small header block |
216 | * describing the number of bits in the BitString to the file described | 228 | * describing the number of bits in the BitString to the file described |
217 | * by the given file descriptor. The data writen is purely sequential and | 229 | * by the given file descriptor. The data writen is purely sequential |
218 | * probably not too easy to read by other mechanisms, although the | 230 | * and probably not too easy to read by other mechanisms, although the |
219 | * readFromFile function should always be able to do it. This function | 231 | * readFromFile function should always be able to do it. This function |
220 | * does not open nor close the file pointed to by fh. | 232 | * does not open nor close the file pointed to by fh. |
221 | *@param fh The file descriptor of the file to write the data to. | 233 | *@param fh The file descriptor of the file to write the data to. |
222 | *@returns true if the operation completed without error, false otherwise. | 234 | *@returns true if the operation completed without error, false |
235 | * otherwise. | ||
223 | */ | 236 | */ |
224 | //bool writeToFile( FILE *fh ); | 237 | //bool writeToFile( FILE *fh ); |
225 | 238 | ||
@@ -229,21 +242,23 @@ namespace Bu | |||
229 | * original BitString that it may be replacing. This function does not | 242 | * original BitString that it may be replacing. This function does not |
230 | * open nor close the file pointed to by fh. | 243 | * open nor close the file pointed to by fh. |
231 | *@param fh The file descriptor to try to read the data from. | 244 | *@param fh The file descriptor to try to read the data from. |
232 | *@returns true if the operation completed without error, false otherwise. | 245 | *@returns true if the operation completed without error, false |
246 | * otherwise. | ||
233 | */ | 247 | */ |
234 | //bool readFromFile( FILE *fh ); | 248 | //bool readFromFile( FILE *fh ); |
235 | 249 | ||
236 | //operators | 250 | //operators |
237 | BitString &operator=( const BitString &xSrc ); | 251 | BitString &operator=( const BitString &xSrc ); |
238 | BitString operator~(); | 252 | BitString operator~(); |
239 | BitString operator<<( const long nAmt ); | 253 | BitString operator<<( const long iAmt ); |
240 | BitString operator>>( const long nAmt ); | 254 | BitString operator>>( const long iAmt ); |
241 | 255 | ||
242 | private: | 256 | private: |
243 | void fixup(); | 257 | void fixup(); |
258 | void setMask(); | ||
244 | unsigned char *caData; | 259 | unsigned char *caData; |
245 | long nBits; | 260 | long iBits; |
246 | long nBytes; | 261 | long iBytes; |
247 | unsigned char cTopByteMask; | 262 | unsigned char cTopByteMask; |
248 | }; | 263 | }; |
249 | }; | 264 | }; |