mpdm_a.c

   1 /*
   2
   3     MPDM - Minimum Profit Data Manager
   4     Copyright (C) 2003/2010 Angel Ortega <angel@triptico.com>
   5
   6     mpdm_a.c - Array management
   7
   8     This program is free software; you can redistribute it and/or
   9     modify it under the terms of the GNU General Public License
  10     as published by the Free Software Foundation; either version 2
  11     of the License, or (at your option) any later version.
  12
  13     This program is distributed in the hope that it will be useful,
  14     but WITHOUT ANY WARRANTY; without even the implied warranty of
  15     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16     GNU General Public License for more details.
  17
  18     You should have received a copy of the GNU General Public License
  19     along with this program; if not, write to the Free Software
  20     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  21
  22     http://www.triptico.com
  23
  24 */
  25
  26 #include "config.h"
  27
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <string.h>
  31 #include <wchar.h>
  32
  33 #include "mpdm.h"
  34
  35
  36 /** data **/
  37
  38 /* sorting callback code */
  39 static mpdm_t sort_cb = NULL;
  40
  41
  42 /** code **/
  43
  44 mpdm_t mpdm_new_a(int flags, int size)
  45 /* creates a new array value */
  46 {
  47         mpdm_t v;
  48
  49         /* creates and expands */
  50         if ((v = mpdm_new(flags | MPDM_MULTIPLE, NULL, 0)) != NULL)
  51                 mpdm_expand(v, 0, size);
  52
  53         return v;
  54 }
  55
  56
  57 static int wrap_offset(const mpdm_t a, int offset)
  58 /* manages negative offsets */
  59 {
  60         if (offset < 0)
  61                 offset = mpdm_size(a) + offset;
  62
  63         return offset;
  64 }
  65
  66
  67 mpdm_t mpdm_aclone(const mpdm_t v)
  68 /* clones a multiple value */
  69 {
  70         mpdm_t w;
  71         int n;
  72
  73         /* creates a similar value */
  74         w = mpdm_new_a(v->flags, v->size);
  75
  76         /* fills each element with duplicates of the original */
  77         for (n = 0; n < w->size; n++)
  78                 mpdm_aset(w, mpdm_clone(mpdm_aget(v, n)), n);
  79
  80         return w;
  81 }
  82
  83
  84 /* interface */
  85
  86 /**
  87  * mpdm_expand - Expands an array.
  88  * @a: the array
  89  * @offset: insertion offset
  90  * @num: number of elements to insert
  91  *
  92  * Expands an array value, inserting @num elements (initialized
  93  * to NULL) at the specified @offset.
  94  * [Arrays]
  95  */
  96 mpdm_t mpdm_expand(mpdm_t a, int offset, int num)
  97 {
  98         int n;
  99         mpdm_t *p;
 100
 101         /* sanity checks */
 102         if (num <= 0)
 103                 return a;
 104
 105         /* add size */
 106         a->size += num;
 107
 108         /* expand, or fail */
 109         if ((p = (mpdm_t *) realloc((mpdm_t *)a->data, a->size * sizeof(mpdm_t))) == NULL)
 110                 return NULL;
 111
 112         /* moves up from top of the array */
 113         for (n = a->size - 1; n >= offset + num; n--)
 114                 p[n] = p[n - num];
 115
 116         /* fills the new space with blanks */
 117         for (; n >= offset; n--)
 118                 p[n] = NULL;
 119
 120         a->data = p;
 121
 122         return a;
 123 }
 124
 125
 126 /**
 127  * mpdm_collapse - Collapses an array.
 128  * @a: the array
 129  * @offset: deletion offset
 130  * @num: number of elements to collapse
 131  *
 132  * Collapses an array value, deleting @num elements at
 133  * the specified @offset.
 134  * [Arrays]
 135  */
 136 mpdm_t mpdm_collapse(mpdm_t a, int offset, int num)
 137 {
 138         int n;
 139         mpdm_t *p;
 140
 141         /* sanity checks */
 142         if (num <= 0)
 143                 return a;
 144
 145         /* don't try to delete beyond the limit */
 146         if (offset + num > a->size)
 147                 num = a->size - offset;
 148
 149         p = (mpdm_t *) a->data;
 150
 151         /* unrefs the about-to-be-deleted elements */
 152         for (n = offset; n < offset + num; n++)
 153                 mpdm_unref(p[n]);
 154
 155         /* array is now shorter */
 156         a->size -= num;
 157
 158         /* moves down the elements */
 159         for (n = offset; n < a->size; n++)
 160                 p[n] = p[n + num];
 161
 162         /* finally shrinks the memory block */
 163         if ((a->data = realloc(p, a->size * sizeof(mpdm_t))) == NULL)
 164                 return NULL;
 165
 166         return a;
 167 }
 168
 169
 170 /**
 171  * mpdm_aset - Sets the value of an array's element.
 172  * @a: the array
 173  * @e: the element to be assigned
 174  * @offset: the subscript of the element
 175  *
 176  * Sets the element of the array @a at @offset to be the @e value.
 177  * Returns the previous element.
 178  * [Arrays]
 179  */
 180 mpdm_t mpdm_aset(mpdm_t a, mpdm_t e, int offset)
 181 {
 182         mpdm_t v;
 183         mpdm_t *p;
 184
 185         offset = wrap_offset(a, offset);
 186
 187         /* boundary checks */
 188         if (offset < 0)
 189                 return NULL;
 190
 191         /* if the array is shorter than offset, expand to make room for it */
 192         if (offset >= mpdm_size(a))
 193                 if (mpdm_expand(a, mpdm_size(a), offset - mpdm_size(a) + 1) == NULL)
 194                         return NULL;
 195
 196         p = (mpdm_t *) a->data;
 197
 198         /* assigns and references */
 199         mpdm_ref(e);
 200         v = mpdm_unref(p[offset]);
 201         p[offset] = e;
 202
 203         return v;
 204 }
 205
 206
 207 /**
 208  * mpdm_aget - Gets an element of an array.
 209  * @a: the array
 210  * @offset: the subscript of the element
 211  *
 212  * Returns the element at @offset of the array @a.
 213  * [Arrays]
 214  */
 215 mpdm_t mpdm_aget(const mpdm_t a, int offset)
 216 {
 217         mpdm_t *p;
 218
 219         offset = wrap_offset(a, offset);
 220
 221         /* boundary checks */
 222         if (offset < 0 || offset >= mpdm_size(a))
 223                 return NULL;
 224
 225         p = (mpdm_t *) a->data;
 226
 227         return p[offset];
 228 }
 229
 230
 231 /**
 232  * mpdm_ins - Insert an element in an array.
 233  * @a: the array
 234  * @e: the element to be inserted
 235  * @offset: subscript where the element is going to be inserted
 236  *
 237  * Inserts the @e value in the @a array at @offset.
 238  * Further elements are pushed up, so the array increases its size
 239  * by one. Returns the inserted element.
 240  * [Arrays]
 241  */
 242 mpdm_t mpdm_ins(mpdm_t a, mpdm_t e, int offset)
 243 {
 244         offset = wrap_offset(a, offset);
 245
 246         /* open room and set value */
 247         if (mpdm_expand(a, offset, 1))
 248                 mpdm_aset(a, e, offset);
 249
 250         return e;
 251 }
 252
 253
 254 /**
 255  * mpdm_adel - Deletes an element of an array.
 256  * @a: the array
 257  * @offset: subscript of the element to be deleted
 258  *
 259  * Deletes the element at @offset of the @a array. The array
 260  * is shrinked by one. If @offset is negative, is counted from
 261  * the end of the array (so a value of -1 means delete the
 262  * last element of the array).
 263  *
 264  * Returns the deleted element.
 265  * [Arrays]
 266  */
 267 mpdm_t mpdm_adel(mpdm_t a, int offset)
 268 {
 269         mpdm_t v;
 270
 271         if (a == NULL || mpdm_size(a) == 0)
 272                 return NULL;
 273
 274         offset = wrap_offset(a, offset);
 275
 276         /* gets current value */
 277         v = mpdm_aget(a, offset);
 278
 279         /* shrinks the array */
 280         mpdm_collapse(a, offset, 1);
 281
 282         return v;
 283 }
 284
 285
 286 /**
 287  * mpdm_shift - Extracts the first element of an array.
 288  * @a: the array
 289  *
 290  * Extracts the first element of the array. The array
 291  * is shrinked by one.
 292  *
 293  * Returns the deleted element.
 294  * [Arrays]
 295  */
 296 mpdm_t mpdm_shift(mpdm_t a)
 297 {
 298         return mpdm_adel(a, 0);
 299 }
 300
 301
 302 /**
 303  * mpdm_push - Pushes a value into an array.
 304  * @a: the array
 305  * @e: the value
 306  *
 307  * Pushes a value into an array (i.e. inserts at the end).
 308  * [Arrays]
 309  */
 310 mpdm_t mpdm_push(mpdm_t a, mpdm_t e)
 311 {
 312         /* inserts at the end */
 313         return mpdm_ins(a, e, mpdm_size(a));
 314 }
 315
 316
 317 /**
 318  * mpdm_pop - Pops a value from an array.
 319  * @a: the array
 320  *
 321  * Pops a value from the array (i.e. deletes from the end
 322  * and returns it).
 323  * [Arrays]
 324  */
 325 mpdm_t mpdm_pop(mpdm_t a)
 326 {
 327         /* deletes from the end */
 328         return mpdm_adel(a, -1);
 329 }
 330
 331
 332 /**
 333  * mpdm_queue - Implements a queue in an array.
 334  * @a: the array
 335  * @e: the element to be pushed
 336  * @size: maximum size of array
 337  *
 338  * Pushes the @e element into the @a array. If the array already has
 339  * @size elements, the first (oldest) element is deleted from the
 340  * queue and returned.
 341  *
 342  * Returns the deleted element, or NULL if the array doesn't have
 343  * @size elements yet.
 344  * [Arrays]
 345  */
 346 mpdm_t mpdm_queue(mpdm_t a, mpdm_t e, int size)
 347 {
 348         mpdm_t v = NULL;
 349
 350         /* zero size is nonsense */
 351         if (size == 0)
 352                 return NULL;
 353
 354         /* loop until a has the desired size */
 355         while (mpdm_size(a) > size - 1)
 356                 v = mpdm_shift(a);
 357
 358         mpdm_push(a, e);
 359         return v;
 360 }
 361
 362
 363 static int seek(const mpdm_t a, const mpdm_t k, const wchar_t *ks, int step)
 364 {
 365         int n;
 366
 367         /* avoid stupid steps */
 368         if (step <= 0)
 369                 step = 1;
 370
 371         for (n = 0; n < mpdm_size(a); n += step) {
 372                 int r;
 373
 374                 mpdm_t v = mpdm_aget(a, n);
 375
 376                 r = ks ? mpdm_cmp_s(v, ks) : mpdm_cmp(v, k);
 377
 378                 if (r == 0)
 379                         return n;
 380         }
 381
 382         return -1;
 383 }
 384
 385
 386 /**
 387  * mpdm_seek - Seeks a value in an array (sequential).
 388  * @a: the array
 389  * @k: the key
 390  * @step: number of elements to step
 391  *
 392  * Seeks sequentially the value @k in the @a array in
 393  * increments of @step. A complete search should use a step of 1.
 394  * Returns the offset of the element if found, or -1 otherwise.
 395  * [Arrays]
 396  */
 397 int mpdm_seek(const mpdm_t a, const mpdm_t k, int step)
 398 {
 399         return seek(a, k, NULL, step);
 400 }
 401
 402
 403 /**
 404  * mpdm_seek_s - Seeks a value in an array (sequential, string version).
 405  * @a: the array
 406  * @k: the key
 407  * @step: number of elements to step
 408  *
 409  * Seeks sequentially the value @k in the @a array in
 410  * increments of @step. A complete search should use a step of 1.
 411  * Returns the offset of the element if found, or -1 otherwise.
 412  * [Arrays]
 413  */
 414 int mpdm_seek_s(const mpdm_t a, const wchar_t *k, int step)
 415 {
 416         return seek(a, NULL, k, step);
 417 }
 418
 419
 420 static int bseek(const mpdm_t a, const mpdm_t k, const wchar_t *ks, int step, int *pos)
 421 {
 422         int b, t, n, c;
 423
 424         /* avoid stupid steps */
 425         if (step <= 0)
 426                 step = 1;
 427
 428         b = 0;
 429         t = (mpdm_size(a) - 1) / step;
 430
 431         while (t >= b) {
 432                 mpdm_t v;
 433
 434                 n = (b + t) / 2;
 435                 if ((v = mpdm_aget(a, n * step)) == NULL)
 436                         break;
 437
 438                 c = ks ? mpdm_cmp_s(v, ks) : mpdm_cmp(v, k);
 439
 440                 if (c == 0)
 441                         return n * step;
 442                 else
 443                 if (c > 0)
 444                         t = n - 1;
 445                 else
 446                         b = n + 1;
 447         }
 448
 449         if (pos != NULL)
 450                 *pos = b * step;
 451
 452         return -1;
 453 }
 454
 455
 456 /**
 457  * mpdm_bseek - Seeks a value in an array (binary).
 458  * @a: the ordered array
 459  * @k: the key
 460  * @step: number of elements to step
 461  * @pos: the position where the element should be, if it's not found
 462  *
 463  * Seeks the value @k in the @a array in increments of @step.
 464  * The array should be sorted to work correctly. A complete search
 465  * should use a step of 1.
 466  *
 467  * If the element is found, returns the offset of the element
 468  * as a positive number; otherwise, -1 is returned and the position
 469  * where the element should be is stored in @pos. You can set @pos
 470  * to NULL if you don't mind.
 471  * [Arrays]
 472  */
 473 int mpdm_bseek(const mpdm_t a, const mpdm_t k, int step, int *pos)
 474 {
 475         return bseek(a, k, NULL, step, pos);
 476 }
 477
 478
 479 /**
 480  * mpdm_bseek_s - Seeks a value in an array (binary, string version).
 481  * @a: the ordered array
 482  * @k: the key
 483  * @step: number of elements to step
 484  * @pos: the position where the element should be, if it's not found
 485  *
 486  * Seeks the value @k in the @a array in increments of @step.
 487  * The array should be sorted to work correctly. A complete search
 488  * should use a step of 1.
 489  *
 490  * If the element is found, returns the offset of the element
 491  * as a positive number; otherwise, -1 is returned and the position
 492  * where the element should be is stored in @pos. You can set @pos
 493  * to NULL if you don't mind.
 494  * [Arrays]
 495  */
 496 int mpdm_bseek_s(const mpdm_t a, const wchar_t *k, int step, int *pos)
 497 {
 498         return bseek(a, NULL, k, step, pos);
 499 }
 500
 501
 502 static int sort_cmp(const void *s1, const void *s2)
 503 /* qsort help function */
 504 {
 505         int ret = 0;
 506
 507         /* if callback is NULL, use basic value comparisons */
 508         if (sort_cb == NULL)
 509                 ret = mpdm_cmp(*(mpdm_t *) s1, *(mpdm_t *) s2);
 510         else {
 511                 /* executes the callback and converts to integer */
 512                 ret = mpdm_ival(mpdm_exec_2(sort_cb,
 513                                             (mpdm_t) * ((mpdm_t *) s1),
 514                                             (mpdm_t) * ((mpdm_t *) s2)));
 515         }
 516
 517         return ret;
 518 }
 519
 520
 521 /**
 522  * mpdm_sort - Sorts an array.
 523  * @a: the array
 524  * @step: increment step
 525  *
 526  * Sorts the array. @step is the number of elements to group together.
 527  *
 528  * Returns the sorted array (the original one is left untouched).
 529  * [Arrays]
 530  */
 531 mpdm_t mpdm_sort(const mpdm_t a, int step)
 532 {
 533         return mpdm_sort_cb(a, step, NULL);
 534 }
 535
 536
 537 /**
 538  * mpdm_sort_cb - Sorts an array with a special sorting function.
 539  * @a: the array
 540  * @step: increment step
 541  * @asort_cb: sorting function
 542  *
 543  * Sorts the array. @step is the number of elements to group together.
 544  * For each pair of elements being sorted, the executable mpdm_t value
 545  * @sort_cb is called with an array containing the two elements as
 546  * argument. It must return a signed numerical mpdm_t value indicating
 547  * the sorting order.
 548  *
 549  * Returns the sorted array (the original one is left untouched).
 550  * [Arrays]
 551  */
 552 mpdm_t mpdm_sort_cb(const mpdm_t a, int step, mpdm_t cb)
 553 {
 554         mpdm_t n;
 555
 556         if (a == NULL)
 557                 return NULL;
 558
 559         /* creates a copy to be sorted */
 560         n = mpdm_clone(a);
 561
 562         sort_cb = cb;
 563
 564         /* references the array and the code, as the latter
 565            can include anything (including sweeping) */
 566         mpdm_ref(n);
 567         mpdm_ref(sort_cb);
 568
 569         qsort((mpdm_t *)n->data, mpdm_size(n) / step, sizeof(mpdm_t) * step, sort_cmp);
 570
 571         /* unreferences */
 572         mpdm_unref(sort_cb);
 573         mpdm_unref(n);
 574
 575         sort_cb = NULL;
 576
 577         return n;
 578 }
 579
 580
 581 /**
 582  * mpdm_split_s - Separates a string into an array of pieces (string version).
 583  * @s: the separator
 584  * @v: the value to be separated
 585  *
 586  * Separates the @v string value into an array of pieces, using @s
 587  * as a separator.
 588  *
 589  * If the separator is NULL, the string is splitted by characters.
 590  *
 591  * If the string does not contain the separator, an array holding
 592  * the complete string is returned.
 593  * [Arrays]
 594  * [Strings]
 595  */
 596 mpdm_t mpdm_split_s(const wchar_t *s, const mpdm_t v)
 597 {
 598         mpdm_t w;
 599         const wchar_t *ptr;
 600         wchar_t *sptr;
 601         int ss;
 602
 603         /* nothing to split? */
 604         if (v == NULL)
 605                 return NULL;
 606
 607         w = MPDM_A(0);
 608
 609         /* NULL separator? special case: split string in characters */
 610         if (s == NULL) {
 611                 for (ptr = mpdm_string(v); ptr && *ptr != '\0'; ptr++)
 612                         mpdm_push(w, MPDM_NS(ptr, 1));
 613
 614                 return w;
 615         }
 616
 617         ss = wcslen(s);
 618
 619         /* travels the string finding separators and creating new values */
 620         for (ptr = v->data;
 621                      *ptr != L'\0' && (sptr = wcsstr(ptr, s)) != NULL;
 622                      ptr = sptr + ss)
 623                 mpdm_push(w, MPDM_NS(ptr, sptr - ptr));
 624
 625         /* add last part */
 626         mpdm_push(w, MPDM_S(ptr));
 627
 628         return w;
 629 }
 630
 631
 632 /**
 633  * mpdm_split - Separates a string into an array of pieces.
 634  * @s: the separator
 635  * @v: the value to be separated
 636  *
 637  * Separates the @v string value into an array of pieces, using @s
 638  * as a separator.
 639  *
 640  * If the separator is NULL, the string is splitted by characters.
 641  *
 642  * If the string does not contain the separator, an array holding
 643  * the complete string is returned.
 644  * [Arrays]
 645  * [Strings]
 646  */
 647 mpdm_t mpdm_split(const mpdm_t s, const mpdm_t v)
 648 {
 649         wchar_t *ss = NULL;
 650
 651         if (s != NULL)
 652                 ss = (wchar_t *)s->data;
 653
 654         return mpdm_split_s(ss, v);
 655 }
 656
 657
 658 /**
 659  * mpdm_join_s - Joins all elements of an array into one (string version).
 660  * @s: joiner string
 661  * @a: array to be joined
 662  *
 663  * Joins all elements from @a into one string, using @s as a glue.
 664  * [Arrays]
 665  * [Strings]
 666  */
 667 mpdm_t mpdm_join_s(const wchar_t *s, const mpdm_t a)
 668 {
 669         int n;
 670         wchar_t *ptr = NULL;
 671         int l = 0;
 672         int ss;
 673
 674         /* if a is not an array, return it as is */
 675         if (!MPDM_IS_ARRAY(a))
 676                 return a;
 677
 678         /* adds the first string */
 679         ptr = mpdm_pokev(ptr, &l, mpdm_aget(a, 0));
 680
 681         ss = s ? wcslen(s) : 0;
 682
 683         for (n = 1; n < mpdm_size(a); n++) {
 684                 /* add separator */
 685                 ptr = mpdm_pokewsn(ptr, &l, s, ss);
 686
 687                 /* add element */
 688                 ptr = mpdm_pokev(ptr, &l, mpdm_aget(a, n));
 689         }
 690
 691         if (ptr == NULL)
 692                 return NULL;
 693
 694         ptr = mpdm_poke(ptr, &l, L"", 1, sizeof(wchar_t));
 695         return MPDM_ENS(ptr, l - 1);
 696 }
 697
 698
 699 /**
 700  * mpdm_join - Joins all elements of an array into one.
 701  * @s: joiner string
 702  * @a: array to be joined
 703  *
 704  * Joins all elements from @a into one string, using @s as a glue.
 705  * [Arrays]
 706  * [Strings]
 707  */
 708 mpdm_t mpdm_join(const mpdm_t s, const mpdm_t a)
 709 {
 710         return mpdm_join_s(s ? mpdm_string(s) : NULL, a);
 711 }