WINGs/data.c

   1 /*
   2  *  WINGs WMData function library
   3  *
   4  *  Copyright (c) 1999-2000 Dan Pascu
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19  */
  20
  21
  22
  23 #include <string.h>
  24 #include "WUtil.h"
  25
  26
  27 typedef struct W_Data {
  28     unsigned   length;      /* How many bytes we have */
  29     unsigned   capacity;    /* How many bytes it can hold */
  30     unsigned   growth;      /* How much to grow */
  31     void       *bytes;      /* Actual data */
  32     unsigned   retainCount;
  33     WMFreeDataProc *destructor;
  34     int        format;      /* 0, 8, 16 or 32 */
  35 } W_Data;
  36
  37
  38
  39
  40 /* Creating and destroying data objects */
  41
  42 WMData*
  43 WMCreateDataWithCapacity(unsigned capacity)
  44 {
  45     WMData *aData;
  46
  47     aData = (WMData*)wmalloc(sizeof(WMData));
  48
  49     if (capacity>0)
  50         aData->bytes = wmalloc(capacity);
  51     else
  52         aData->bytes = NULL;
  53
  54     aData->capacity = capacity;
  55     aData->growth = capacity/2 > 0 ? capacity/2 : 1;
  56     aData->length = 0;
  57     aData->retainCount = 1;
  58     aData->format = 0;
  59     aData->destructor = wfree;
  60
  61     return aData;
  62 }
  63
  64
  65 WMData*
  66 WMCreateDataWithLength(unsigned length)
  67 {
  68     WMData *aData;
  69
  70     aData = WMCreateDataWithCapacity(length);
  71     if (length>0) {
  72         memset(aData->bytes, 0, length);
  73         aData->length = length;
  74     }
  75
  76     return aData;
  77 }
  78
  79
  80 WMData*
  81 WMCreateDataWithBytes(void *bytes, unsigned length)
  82 {
  83     WMData *aData;
  84
  85     aData = WMCreateDataWithCapacity(length);
  86     aData->length = length;
  87     memcpy(aData->bytes, bytes, length);
  88
  89     return aData;
  90 }
  91
  92
  93 WMData*
  94 WMCreateDataWithBytesNoCopy(void *bytes, unsigned length,
  95                             WMFreeDataProc *destructor)
  96 {
  97     WMData *aData;
  98
  99     aData = (WMData*)wmalloc(sizeof(WMData));
 100     aData->length = length;
 101     aData->capacity = length;
 102     aData->growth = length/2 > 0 ? length/2 : 1;
 103     aData->bytes = bytes;
 104     aData->retainCount = 1;
 105     aData->format = 0;
 106     aData->destructor = destructor;
 107
 108     return aData;
 109 }
 110
 111
 112 WMData*
 113 WMCreateDataWithData(WMData *aData)
 114 {
 115     WMData *newData;
 116
 117     if (aData->length > 0) {
 118         newData = WMCreateDataWithBytes(aData->bytes, aData->length);
 119     } else {
 120         newData = WMCreateDataWithCapacity(0);
 121     }
 122     newData->format = aData->format;
 123
 124     return newData;
 125 }
 126
 127
 128 WMData*
 129 WMRetainData(WMData *aData)
 130 {
 131     aData->retainCount++;
 132     return aData;
 133 }
 134
 135
 136 void
 137 WMReleaseData(WMData *aData)
 138 {
 139     aData->retainCount--;
 140     if (aData->retainCount > 0)
 141         return;
 142     if (aData->bytes!=NULL && aData->destructor!=NULL) {
 143         aData->destructor(aData->bytes);
 144     }
 145     wfree(aData);
 146 }
 147
 148
 149
 150 /* Adjusting capacity */
 151
 152 void
 153 WMSetDataCapacity(WMData *aData, unsigned capacity)
 154 {
 155     if (aData->capacity != capacity) {
 156         aData->bytes = wrealloc(aData->bytes, capacity);
 157         aData->capacity = capacity;
 158         aData->growth = capacity/2 > 0 ? capacity/2 : 1;
 159     }
 160     if (aData->length > capacity) {
 161         aData->length = capacity;
 162     }
 163 }
 164
 165
 166 void
 167 WMSetDataLength(WMData *aData, unsigned length)
 168 {
 169     if (length > aData->capacity) {
 170         WMSetDataCapacity(aData, length);
 171     }
 172     if (length > aData->length) {
 173         memset((unsigned char*)aData->bytes + aData->length, 0,
 174                length - aData->length);
 175     }
 176     aData->length = length;
 177 }
 178
 179
 180 void
 181 WMSetDataFormat(WMData *aData, unsigned format)
 182 {
 183     aData->format = format;
 184 }
 185
 186
 187 void
 188 WMIncreaseDataLengthBy(WMData *aData, unsigned extraLength)
 189 {
 190     WMSetDataLength(aData, aData->length + extraLength);
 191 }
 192
 193
 194 /* Accessing data */
 195
 196 const void*
 197 WMDataBytes(WMData *aData)
 198 {
 199     return aData->bytes;
 200 }
 201
 202
 203 void
 204 WMGetDataBytes(WMData *aData, void *buffer)
 205 {
 206     wassertr(aData->length > 0);
 207
 208     memcpy(buffer, aData->bytes, aData->length);
 209 }
 210
 211
 212 unsigned
 213 WMGetDataFormat(WMData *aData)
 214 {
 215     return aData->format;
 216 }
 217
 218
 219 void
 220 WMGetDataBytesWithLength(WMData *aData, void *buffer, unsigned length)
 221 {
 222     wassertr(aData->length > 0);
 223     wassertr(length <= aData->length);
 224
 225     memcpy(buffer, aData->bytes, length);
 226 }
 227
 228
 229 void
 230 WMGetDataBytesWithRange(WMData *aData, void *buffer, WMRange aRange)
 231 {
 232     wassertr(aRange.position < aData->length);
 233     wassertr(aRange.count <= aData->length-aRange.position);
 234
 235     memcpy(buffer, (unsigned char*)aData->bytes + aRange.position,
 236            aRange.count);
 237 }
 238
 239
 240 WMData*
 241 WMGetSubdataWithRange(WMData *aData, WMRange aRange)
 242 {
 243     void *buffer;
 244     WMData *newData;
 245
 246     if (aRange.count <= 0)
 247         return WMCreateDataWithCapacity(0);
 248
 249     buffer = wmalloc(aRange.count);
 250     WMGetDataBytesWithRange(aData, buffer, aRange);
 251     newData = WMCreateDataWithBytesNoCopy(buffer, aRange.count, wfree);
 252     newData->format = aData->format;
 253
 254     return newData;
 255 }
 256
 257
 258 /* Testing data */
 259
 260 Bool
 261 WMIsDataEqualToData(WMData *aData, WMData *anotherData)
 262 {
 263     if (aData->length != anotherData->length)
 264         return False;
 265     else if (!aData->bytes && !anotherData->bytes) /* both are empty */
 266         return True;
 267     else if (!aData->bytes || !anotherData->bytes) /* one of them is empty */
 268         return False;
 269     return (memcmp(aData->bytes, anotherData->bytes, aData->length)==0);
 270 }
 271
 272
 273 unsigned
 274 WMGetDataLength(WMData *aData)
 275 {
 276     return aData->length;
 277 }
 278
 279
 280 /* Adding data */
 281 void
 282 WMAppendDataBytes(WMData *aData, void *bytes, unsigned length)
 283 {
 284     unsigned oldLength = aData->length;
 285     unsigned newLength = oldLength + length;
 286
 287     if (newLength > aData->capacity) {
 288         unsigned nextCapacity = aData->capacity + aData->growth;
 289         unsigned nextGrowth = aData->capacity ? aData->capacity : 1;
 290
 291         while (nextCapacity < newLength) {
 292             unsigned tmp = nextCapacity + nextGrowth;
 293
 294             nextGrowth = nextCapacity;
 295             nextCapacity = tmp;
 296         }
 297         WMSetDataCapacity(aData, nextCapacity);
 298         aData->growth = nextGrowth;
 299     }
 300     memcpy((unsigned char*)aData->bytes + oldLength, bytes, length);
 301     aData->length = newLength;
 302 }
 303
 304
 305 void
 306 WMAppendData(WMData *aData, WMData *anotherData)
 307 {
 308     if (anotherData->length > 0)
 309         WMAppendDataBytes(aData, anotherData->bytes, anotherData->length);
 310 }
 311
 312
 313
 314 /* Modifying data */
 315
 316 void
 317 WMReplaceDataBytesInRange(WMData *aData, WMRange aRange, void *bytes)
 318 {
 319     wassertr(aRange.position < aData->length);
 320     wassertr(aRange.count <= aData->length-aRange.position);
 321
 322     memcpy((unsigned char*)aData->bytes + aRange.position, bytes, aRange.count);
 323 }
 324
 325
 326 void
 327 WMResetDataBytesInRange(WMData *aData, WMRange aRange)
 328 {
 329     wassertr(aRange.position < aData->length);
 330     wassertr(aRange.count <= aData->length-aRange.position);
 331
 332     memset((unsigned char*)aData->bytes + aRange.position, 0, aRange.count);
 333 }
 334
 335
 336 void
 337 WMSetData(WMData *aData, WMData *anotherData)
 338 {
 339     unsigned length = anotherData->length;
 340
 341     WMSetDataCapacity(aData, length);
 342     if (length > 0)
 343         memcpy(aData->bytes, anotherData->bytes, length);
 344     aData->length = length;
 345 }
 346
 347
 348 /* Storing data */
 349
 350