| 1 | /*************** CSort C Program Source Code File (.CPP) ***************/ |
| 2 | /* PROGRAM NAME: CSORT */ |
| 3 | /* ------------- */ |
| 4 | /* Version 2.2 */ |
| 5 | /* */ |
| 6 | /* COPYRIGHT: */ |
| 7 | /* ---------- */ |
| 8 | /* (C) Copyright to the author Olivier Bertrand 1995-2016 */ |
| 9 | /* */ |
| 10 | /* WHAT THIS PROGRAM DOES: */ |
| 11 | /* ----------------------- */ |
| 12 | /* This program is the C++ sorting routines that use qsort/insert */ |
| 13 | /* algorithm and produces an offset/break table while sorting. */ |
| 14 | /* */ |
| 15 | /* WHAT YOU NEED TO COMPILE THIS PROGRAM: */ |
| 16 | /* -------------------------------------- */ |
| 17 | /* */ |
| 18 | /* REQUIRED FILES: */ |
| 19 | /* --------------- */ |
| 20 | /* csort.cpp - Source code */ |
| 21 | /* */ |
| 22 | /* REQUIRED LIBRARIES: */ |
| 23 | /* ------------------- */ |
| 24 | /* OS2DEF.LIB - OS2 libray definition subset. */ |
| 25 | /* */ |
| 26 | /* REQUIRED PROGRAMS: */ |
| 27 | /* ------------------ */ |
| 28 | /* Microsoft C++ Compiler */ |
| 29 | /* or GNU Compiler/Linker */ |
| 30 | /* or BORLAND 4.5 C++ compiler */ |
| 31 | /* */ |
| 32 | /* NOTE */ |
| 33 | /* ---- */ |
| 34 | /* These functions are not 64-bits ready. */ |
| 35 | /* */ |
| 36 | /***********************************************************************/ |
| 37 | |
| 38 | /***********************************************************************/ |
| 39 | /* Include relevant MariaDB header file. */ |
| 40 | /***********************************************************************/ |
| 41 | #include "my_global.h" |
| 42 | |
| 43 | /***********************************************************************/ |
| 44 | /* Include application header files */ |
| 45 | /***********************************************************************/ |
| 46 | #include <stdlib.h> /* C standard library */ |
| 47 | #include <string.h> /* String manipulation declares */ |
| 48 | #include <stdio.h> /* Required for sprintf declare */ |
| 49 | #if defined(_DEBUG) |
| 50 | #include <assert.h> /* Assertion routine declares */ |
| 51 | #endif |
| 52 | |
| 53 | /***********************************************************************/ |
| 54 | /* Include CSort class header file */ |
| 55 | /***********************************************************************/ |
| 56 | #include "global.h" |
| 57 | #include "plgdbsem.h" /* For MBLOCK type definition */ |
| 58 | #include "csort.h" /* CSort class definition */ |
| 59 | #include "osutil.h" |
| 60 | |
| 61 | #if !defined(BIGSORT) |
| 62 | #define BIGSORT 200000 |
| 63 | #endif // !BIGSORT |
| 64 | |
| 65 | /***********************************************************************/ |
| 66 | /* DB static external variables. */ |
| 67 | /***********************************************************************/ |
| 68 | extern MBLOCK Nmblk; /* Used to initialize MBLOCK's */ |
| 69 | |
| 70 | /***********************************************************************/ |
| 71 | /* Initialize the CSORT static members. */ |
| 72 | /***********************************************************************/ |
| 73 | int CSORT::Limit = 0; |
| 74 | double CSORT::Lg2 = log(2.0); |
| 75 | size_t CSORT::Cpn[1000] = {0}; /* Precalculated cmpnum values */ |
| 76 | |
| 77 | /***********************************************************************/ |
| 78 | /* CSORT constructor. */ |
| 79 | /***********************************************************************/ |
| 80 | CSORT::CSORT(bool cns, int th, int mth) |
| 81 | : Pex((int*&)Index.Memp), Pof((int*&)Offset.Memp) |
| 82 | { |
| 83 | G = NULL; |
| 84 | Dup =NULL; |
| 85 | Cons = cns; |
| 86 | Thresh = th; |
| 87 | Mthresh = mth; |
| 88 | Nitem = 0; |
| 89 | Index = Nmblk; |
| 90 | Offset = Nmblk; |
| 91 | Swix = NULL; |
| 92 | Savmax = 0; |
| 93 | Savcur = 0; |
| 94 | Savstep = NULL; |
| 95 | } // end of CSORT constructor |
| 96 | |
| 97 | /***********************************************************************/ |
| 98 | /* CSORT intialization. */ |
| 99 | /***********************************************************************/ |
| 100 | int CSORT::Qsort(PGLOBAL g, int nb) |
| 101 | { |
| 102 | int rc; |
| 103 | |
| 104 | #if defined(_DEBUG) |
| 105 | assert(Index.Size >= nb * sizeof(int)); |
| 106 | #endif |
| 107 | |
| 108 | if (nb > BIGSORT) { |
| 109 | G = g; |
| 110 | Dup = (PDBUSER)g->Activityp->Aptr; |
| 111 | |
| 112 | if (Dup->Proginfo) { |
| 113 | Savstep = Dup->Step; |
| 114 | Savmax = Dup->ProgMax; |
| 115 | Savcur = Dup->ProgCur; |
| 116 | |
| 117 | // Evaluate the number of comparisons that we will do |
| 118 | Dup->ProgMax = Cmpnum(nb); |
| 119 | Dup->ProgCur = 0; |
| 120 | Dup->Step = (char*)PlugSubAlloc(g, NULL, 32); |
| 121 | sprintf((char*)Dup->Step, MSG(SORTING_VAL), nb); |
| 122 | } else |
| 123 | Dup = NULL; |
| 124 | |
| 125 | } else |
| 126 | Dup = NULL; |
| 127 | |
| 128 | Nitem = nb; |
| 129 | |
| 130 | for (int n = 0; n < Nitem; n++) |
| 131 | Pex[n] = n; |
| 132 | |
| 133 | rc = (Cons) ? Qsortc() : Qsortx(); |
| 134 | |
| 135 | if (Dup) { |
| 136 | // Restore any change in progress info settings |
| 137 | // printf("Progcur=%u\n", Dup->ProgCur); |
| 138 | |
| 139 | Dup->Step = Savstep; |
| 140 | Dup->ProgMax = Savmax; |
| 141 | Dup->ProgCur = Savcur; |
| 142 | } // endif Subcor |
| 143 | |
| 144 | return rc; |
| 145 | } // end of QSort |
| 146 | |
| 147 | #if defined(DEBTRACE) |
| 148 | /***********************************************************************/ |
| 149 | /* Debug routine to be used by sort for specific data (dummy as now) */ |
| 150 | /***********************************************************************/ |
| 151 | void CSORT::DebugSort(int ph, int n, int *base, int *mid, int *tmp) |
| 152 | { |
| 153 | htrc("phase=%d n=%d base=%p mid=%p tmp=%p\n" , |
| 154 | ph, n, base, mid, tmp); |
| 155 | } // end of DebugSort |
| 156 | #endif |
| 157 | |
| 158 | /***********************************************************************/ |
| 159 | /* Qsortx: Version adapted from qsortx.c by O.Bertrand */ |
| 160 | /* This version is specialy adapted for Index sorting, meaning that */ |
| 161 | /* the data is not moved, but the Index only is sorted. */ |
| 162 | /* Index array elements are any 4-byte word (a pointer or a int int */ |
| 163 | /* array index), they are not interpreted except by the user provided */ |
| 164 | /* comparison routine which must works accordingly. */ |
| 165 | /* In addition, this program takes care of data in which there is a */ |
| 166 | /* high rate of repetitions. */ |
| 167 | /* CAUTION: the sort algorithm used here is not conservative. Equal */ |
| 168 | /* values will be internally stored in unpredictable order. */ |
| 169 | /* The THRESHold below is the insertion sort threshold, and also the */ |
| 170 | /* threshold for continuing que quicksort partitioning. */ |
| 171 | /* The MTHREShold is where we stop finding a better median. */ |
| 172 | /* These two quantities should be adjusted dynamically depending upon */ |
| 173 | /* the repetition rate of the data. */ |
| 174 | /* Algorithm used: */ |
| 175 | /* First, set up some global parameters for Qstx to share. Then, */ |
| 176 | /* quicksort with Qstx(), and then a cleanup insertion sort ourselves. */ |
| 177 | /* Sound simple? It's not... */ |
| 178 | /***********************************************************************/ |
| 179 | int CSORT::Qsortx(void) |
| 180 | { |
| 181 | register int c; |
| 182 | register int lo, hi, min; |
| 183 | register int i, j, rc = 0; |
| 184 | // To do: rc should be checked for being used uninitialized |
| 185 | int *top; |
| 186 | #ifdef DEBTRACE |
| 187 | int ncp; |
| 188 | |
| 189 | num_comp = 0; |
| 190 | #endif |
| 191 | |
| 192 | /*********************************************************************/ |
| 193 | /* Prepare the Offset array that will be updated during sorts. */ |
| 194 | /*********************************************************************/ |
| 195 | if (Pof) |
| 196 | for (Pof[Nitem] = Nitem, j = 0; j < Nitem; j++) |
| 197 | Pof[j] = 0; |
| 198 | else |
| 199 | j = Nitem + 1; |
| 200 | |
| 201 | /*********************************************************************/ |
| 202 | /* Sort on one or zero element is obvious. */ |
| 203 | /*********************************************************************/ |
| 204 | if (Nitem <= 1) |
| 205 | return Nitem; |
| 206 | |
| 207 | /*********************************************************************/ |
| 208 | /* Thresh seems to be good as (10 * n / rep). But for testing we */ |
| 209 | /* set it directly as one parameter of the Xset function call. */ |
| 210 | /* Note: this should be final as the rep parameter is no more used. */ |
| 211 | /*********************************************************************/ |
| 212 | top = Pex + Nitem; |
| 213 | |
| 214 | #ifdef DEBTRACE |
| 215 | htrc("Qsortx: nitem=%d thresh=%d mthresh=%d\n" , |
| 216 | Nitem, Thresh, Mthresh); |
| 217 | #endif |
| 218 | |
| 219 | /*********************************************************************/ |
| 220 | /* If applicable, do a rough preliminary quick sort. */ |
| 221 | /*********************************************************************/ |
| 222 | if (Nitem >= Thresh) |
| 223 | Qstx(Pex, top); |
| 224 | |
| 225 | #ifdef DEBTRACE |
| 226 | htrc(" after quick sort num_comp=%d\n" , num_comp); |
| 227 | ncp = num_comp; |
| 228 | num_comp = 0; |
| 229 | #ifdef DEBUG2 |
| 230 | DebugSort((Pof) ? 1 : 4, Nitem, Pex, NULL, NULL); |
| 231 | #endif |
| 232 | #endif |
| 233 | |
| 234 | if (Thresh > 2) { |
| 235 | if (Pof) |
| 236 | /*****************************************************************/ |
| 237 | /* The preliminary search for the smallest element has been */ |
| 238 | /* removed so with no sentinel in place, we must check for x */ |
| 239 | /* going below the Pof pointer. For each remaining element */ |
| 240 | /* group from [1] to [n-1], set hi to the index of the element */ |
| 241 | /* AFTER which this one goes. Then, do the standard insertion */ |
| 242 | /* sort shift on an integer at a time basis for each equal */ |
| 243 | /* element group in the frob. */ |
| 244 | /*****************************************************************/ |
| 245 | for (min = hi = 0; min < Nitem; min = hi) { |
| 246 | if (Pof[hi]) { |
| 247 | hi += Pof[hi]; |
| 248 | continue; |
| 249 | } // endif Pof |
| 250 | |
| 251 | Pof[min] = 1; |
| 252 | |
| 253 | #ifdef DEBUG2 |
| 254 | htrc("insert from min=%d\n" , min); |
| 255 | #endif |
| 256 | |
| 257 | for (lo = hi; !Pof[++hi]; lo = hi) { |
| 258 | while (lo >= min && (rc = Qcompare(Pex + lo, Pex + hi)) > 0) |
| 259 | if (Pof[lo] > 0) |
| 260 | lo -= Pof[lo]; |
| 261 | else |
| 262 | return -2; |
| 263 | |
| 264 | if (++lo != hi) { |
| 265 | c = Pex[hi]; |
| 266 | |
| 267 | for (i = j = hi; i > 0; i = j) |
| 268 | if (Pof[i - 1] <= 0) |
| 269 | return -3; |
| 270 | else if ((j -= Pof[i - 1]) >= lo) { |
| 271 | Pex[i] = Pex[j]; |
| 272 | Pof[j + 1] = Pof[i] = Pof[j]; |
| 273 | } else |
| 274 | break; |
| 275 | |
| 276 | Pex[i] = c; |
| 277 | } // endif lo |
| 278 | |
| 279 | if (rc) |
| 280 | Pof[lo] = 1; |
| 281 | else { |
| 282 | i = lo - Pof[lo - 1]; |
| 283 | Pof[lo] = ++Pof[i]; |
| 284 | } // endelse |
| 285 | |
| 286 | #ifdef DEBUG2 |
| 287 | htrc("rc=%d lo=%d hi=%d trx=%d\n" , rc, lo, hi, Pof[lo]); |
| 288 | #endif |
| 289 | |
| 290 | } // endfor hi |
| 291 | |
| 292 | } // endfor min |
| 293 | |
| 294 | else |
| 295 | /*****************************************************************/ |
| 296 | /* Call conservative insertion sort not using/setting offset. */ |
| 297 | /*****************************************************************/ |
| 298 | Istc(Pex, Pex + MY_MIN(Nitem, Thresh), top); |
| 299 | |
| 300 | } // endif Thresh |
| 301 | |
| 302 | #ifdef DEBTRACE |
| 303 | htrc(" after insert sort num_comp=%d\n" , num_comp); |
| 304 | num_comp += ncp; |
| 305 | #endif |
| 306 | |
| 307 | if (Pof) |
| 308 | /*******************************************************************/ |
| 309 | /* Reduce the Offset array. */ |
| 310 | /*******************************************************************/ |
| 311 | for (i = j = 0; i <= Nitem; j++, i += c) { |
| 312 | #ifdef DEBUG2 |
| 313 | htrc(" trxp(%d)=%d trxp(%d)=%d c=%d\n" , |
| 314 | i, Pof[i], j, Pof[j], c); |
| 315 | #endif |
| 316 | if ((c = Pof[i])) |
| 317 | Pof[j] = i; |
| 318 | else |
| 319 | return -4; |
| 320 | |
| 321 | } // endfor i |
| 322 | |
| 323 | return (j - 1); |
| 324 | } // end of Qsortx |
| 325 | |
| 326 | /***********************************************************************/ |
| 327 | /* Qstx: Do a quicksort on index elements (just one int int). */ |
| 328 | /* First, find the median element, and put that one in the first place */ |
| 329 | /* as the discriminator. (This "median" is just the median of the */ |
| 330 | /* first, last and middle elements). (Using this median instead of */ |
| 331 | /* the first element is a big win). Then, the usual partitioning/ */ |
| 332 | /* swapping, followed by moving the discriminator into the right place.*/ |
| 333 | /* Element equal to the discriminator are placed against it, so the */ |
| 334 | /* mid (discriminator) block grows when equal elements exist. This is */ |
| 335 | /* a huge win in case of repartitions with few different elements. */ |
| 336 | /* The mid block being at its final position, its first and last */ |
| 337 | /* elements are marked in the offset list (used to make break list). */ |
| 338 | /* Then, figure out the sizes of the two partitions, do the smaller */ |
| 339 | /* one recursively and the larger one via a repeat of this code. */ |
| 340 | /* Stopping when there are less than THRESH elements in a partition */ |
| 341 | /* and cleaning up with an insertion sort (in our caller) is a huge */ |
| 342 | /* win(?). All data swaps are done in-line, which is space-losing but */ |
| 343 | /* time-saving. (And there are only three places where this is done). */ |
| 344 | /***********************************************************************/ |
| 345 | void CSORT::Qstx(int *base, int *max) |
| 346 | { |
| 347 | register int *i, *j, *jj, *mid, *him, c; |
| 348 | int *tmp; |
| 349 | int lo, hi, rc; |
| 350 | size_t zlo, zhi, cnm; |
| 351 | |
| 352 | zlo = zhi = cnm = 0; // Avoid warning message |
| 353 | |
| 354 | lo = (int)(max - base); // Number of elements as longs |
| 355 | |
| 356 | if (Dup) |
| 357 | cnm = Cmpnum(lo); |
| 358 | |
| 359 | do { |
| 360 | /*******************************************************************/ |
| 361 | /* At the top here, lo is the number of integers of elements in */ |
| 362 | /* the current partition. (Which should be max - base). */ |
| 363 | /* Find the median of the first, last, and middle element and make */ |
| 364 | /* that the middle element. Set j to largest of first and middle. */ |
| 365 | /* If max is larger than that guy, then it's that guy, else */ |
| 366 | /* compare max with loser of first and take larger. Things are */ |
| 367 | /* set up to prefer the middle, then the first in case of ties. */ |
| 368 | /* In addition, hi and rc are set to comparison results. So if hi */ |
| 369 | /* is null, the two high values are equal and if rc is null, the */ |
| 370 | /* two low values are equal. This was used to set which test will */ |
| 371 | /* be made by LE and which one by LT (does not apply anymore). */ |
| 372 | /*******************************************************************/ |
| 373 | him = mid = i = base + (lo >> 1); |
| 374 | hi = rc = 0; |
| 375 | |
| 376 | #ifdef DEBTRACE |
| 377 | tmp = max - 1; |
| 378 | htrc("--> block base=%d size=%d\n" , base - Pex, lo); |
| 379 | DebugSort(2, 0, base, mid, tmp); |
| 380 | #endif |
| 381 | |
| 382 | if (lo >= Mthresh) { |
| 383 | rc = Qcompare((jj = base), i); |
| 384 | j = (rc > 0) ? jj : i; |
| 385 | hi = Qcompare(j, (tmp = max - 1)); |
| 386 | |
| 387 | if (hi > 0 && rc) { |
| 388 | j = (j == jj) ? i : jj; // switch to first loser |
| 389 | |
| 390 | if ((rc = Qcompare(j, tmp)) < 0) |
| 391 | j = tmp; |
| 392 | |
| 393 | } // endif |
| 394 | |
| 395 | if (j != i) { |
| 396 | c = *i; |
| 397 | *i = *j; |
| 398 | *j = c; |
| 399 | } // endif j |
| 400 | |
| 401 | } else if (lo == 2) { |
| 402 | /*****************************************************************/ |
| 403 | /* Small group. Do special quicker processing. */ |
| 404 | /*****************************************************************/ |
| 405 | if ((rc = Qcompare(base, (him = base + 1))) > 0) |
| 406 | c = *base, *base = *him, *him = c; |
| 407 | |
| 408 | if (Pof) |
| 409 | Pof[base - Pex] = Pof[him - Pex] = (rc) ? 1 : 2; |
| 410 | |
| 411 | break; |
| 412 | } // endif lo |
| 413 | |
| 414 | #ifdef DEBTRACE |
| 415 | DebugSort(3, hi, NULL, mid, &rc); |
| 416 | #endif |
| 417 | |
| 418 | /*******************************************************************/ |
| 419 | /* Semi-standard quicksort partitioning/swapping. Added here is */ |
| 420 | /* a test on equality. All values equal to the mid element are */ |
| 421 | /* placed under or over it. Mid block can be also moved when it */ |
| 422 | /* is necessary because the other partition is full. At the end */ |
| 423 | /* of the for loop the mid block is definitely positionned. */ |
| 424 | /*******************************************************************/ |
| 425 | for (i = base, j = max - 1; ;) { |
| 426 | CONT: |
| 427 | while (i < mid) |
| 428 | if ((rc = Qcompare(i, mid)) < 0) |
| 429 | i++; |
| 430 | else if (!rc) { |
| 431 | c = *i; |
| 432 | *i = *(--mid); |
| 433 | *mid = c; |
| 434 | } else |
| 435 | break; |
| 436 | |
| 437 | while (j > him) |
| 438 | if ((rc = Qcompare(him, j)) < 0) |
| 439 | j--; |
| 440 | else if (!rc) { |
| 441 | c = *j; |
| 442 | *j = *(++him); |
| 443 | *him = c; |
| 444 | } else if (i == mid) { // Triple move: |
| 445 | c = *j; // j goes under mid block |
| 446 | *j = *(++him); // val over mid block -> j |
| 447 | *him = *mid++; // and mid block goes one |
| 448 | *i++ = c; // position higher. |
| 449 | } else { // i <-> j |
| 450 | c = *i; |
| 451 | *i++ = *j; |
| 452 | *j-- = c; |
| 453 | goto CONT; |
| 454 | } // endif's |
| 455 | |
| 456 | if (i == mid) |
| 457 | break; |
| 458 | else { // Triple move: |
| 459 | c = *i; // i goes over mid block |
| 460 | *i = *(--mid); // val under mid block -> i |
| 461 | *mid = *him--; // and mid block goes one |
| 462 | *j-- = c; // position lower. |
| 463 | } // endelse |
| 464 | |
| 465 | } // endfor i |
| 466 | |
| 467 | /*******************************************************************/ |
| 468 | /* The mid block being placed at its final position we can now set */ |
| 469 | /* the offset array values indicating break point and block size. */ |
| 470 | /*******************************************************************/ |
| 471 | j = mid; |
| 472 | i = him + 1; |
| 473 | |
| 474 | if (Pof) |
| 475 | Pof[him - Pex] = Pof[mid - Pex] = (int)(i - j); |
| 476 | |
| 477 | /*******************************************************************/ |
| 478 | /* Look at sizes of the two partitions, do the smaller one first */ |
| 479 | /* by recursion, then do the larger one by making sure lo is its */ |
| 480 | /* size, base and max are update correctly, and branching back. */ |
| 481 | /* But only repeat (recursively or by branching) if the partition */ |
| 482 | /* is of at least size THRESH. */ |
| 483 | /*******************************************************************/ |
| 484 | lo = (int)(j - base); |
| 485 | hi = (int)(max - i); |
| 486 | |
| 487 | if (Dup) { // Update progress information |
| 488 | zlo = Cmpnum(lo); |
| 489 | zhi = Cmpnum(hi); |
| 490 | Dup->ProgCur += cnm - (zlo + zhi); |
| 491 | } // endif Dup |
| 492 | |
| 493 | #ifdef DEBTRACE |
| 494 | htrc(" done lo=%d sep=%d hi=%d\n" , lo, i - j, hi); |
| 495 | #endif |
| 496 | |
| 497 | if (lo <= hi) { |
| 498 | if (lo >= Thresh) |
| 499 | Qstx(base, j); |
| 500 | else if (lo == 1 && Pof) |
| 501 | Pof[base - Pex] = 1; |
| 502 | |
| 503 | base = i; |
| 504 | lo = hi; |
| 505 | cnm = zhi; |
| 506 | } else { |
| 507 | if (hi >= Thresh) |
| 508 | Qstx(i, max); |
| 509 | else if (hi == 1 && Pof) |
| 510 | Pof[i - Pex] = 1; |
| 511 | |
| 512 | max = j; |
| 513 | cnm = zlo; |
| 514 | } // endif |
| 515 | |
| 516 | if (lo == 1 && Pof) |
| 517 | Pof[base - Pex] = 1; |
| 518 | |
| 519 | } while (lo >= Thresh); // enddo |
| 520 | |
| 521 | } // end of Qstx |
| 522 | |
| 523 | /***********************************************************************/ |
| 524 | /* Qsortc.c: Version adapted from qsort.c by O.Bertrand */ |
| 525 | /* This version is specialy adapted for Index sorting, meaning that */ |
| 526 | /* the data is not moved, but the Index only is sorted. */ |
| 527 | /* Index array elements are any 4-byte word (a pointer or a int int */ |
| 528 | /* array index), they are not interpreted except by the user provided */ |
| 529 | /* comparison routine which must works accordingly. */ |
| 530 | /* In addition, this program takes care of data in which there is a */ |
| 531 | /* high rate of repetitions. */ |
| 532 | /* NOTE: the sort algorithm used here is conservative. Equal and */ |
| 533 | /* greater than values are internally stored in additional work area. */ |
| 534 | /* The THRESHold below is the insertion sort threshold, and also the */ |
| 535 | /* threshold for continuing que quicksort partitioning. */ |
| 536 | /* The MTHREShold is where we stop finding a better median. */ |
| 537 | /* These two quantities should be adjusted dynamically depending upon */ |
| 538 | /* the repetition rate of the data. */ |
| 539 | /* Algorithm used: */ |
| 540 | /* First, set up some global parameters for Qstc to share. Then, */ |
| 541 | /* quicksort with Qstc(), and then a cleanup insertion sort ourselves.*/ |
| 542 | /* Sound simple? It's not... */ |
| 543 | /***********************************************************************/ |
| 544 | int CSORT::Qsortc(void) |
| 545 | { |
| 546 | register int c; |
| 547 | register int lo, hi, min; |
| 548 | register int i, j, k, m, rc = 0; |
| 549 | // To do: rc should be checked for being used uninitialized |
| 550 | int *max; |
| 551 | #ifdef DEBTRACE |
| 552 | int ncp; |
| 553 | |
| 554 | num_comp = 0; |
| 555 | #endif |
| 556 | |
| 557 | /*********************************************************************/ |
| 558 | /* Prepare the Offset array that will be updated during sorts. */ |
| 559 | /*********************************************************************/ |
| 560 | if (Pof) |
| 561 | for (Pof[Nitem] = Nitem, j = 0; j < Nitem; j++) |
| 562 | Pof[j] = 0; |
| 563 | else |
| 564 | j = Nitem + 1; |
| 565 | |
| 566 | /*********************************************************************/ |
| 567 | /* Sort on one or zero element is obvious. */ |
| 568 | /*********************************************************************/ |
| 569 | if (Nitem <= 1) |
| 570 | return Nitem; |
| 571 | |
| 572 | /*********************************************************************/ |
| 573 | /* Thresh seems to be good as (10 * n / rep). But for testing we */ |
| 574 | /* set it directly as one parameter of the Xset function call. */ |
| 575 | /* Note: this should be final as the rep parameter is no more used. */ |
| 576 | /*********************************************************************/ |
| 577 | max = Pex + Nitem; |
| 578 | |
| 579 | #ifdef DEBTRACE |
| 580 | htrc("Qsortc: nitem=%d thresh=%d mthresh=%d\n" , |
| 581 | Nitem, Thresh, Mthresh); |
| 582 | #endif |
| 583 | |
| 584 | /*********************************************************************/ |
| 585 | /* If applicable, do a rough preliminary conservative quick sort. */ |
| 586 | /*********************************************************************/ |
| 587 | if (Nitem >= Thresh) { |
| 588 | if (!(Swix = (int *)malloc(Nitem * sizeof(int)))) |
| 589 | return -1; |
| 590 | |
| 591 | Qstc(Pex, max); |
| 592 | |
| 593 | free(Swix); |
| 594 | Swix = NULL; |
| 595 | } // endif n |
| 596 | |
| 597 | #ifdef DEBTRACE |
| 598 | htrc(" after quick sort num_comp=%d\n" , num_comp); |
| 599 | ncp = num_comp; |
| 600 | num_comp = 0; |
| 601 | #ifdef DEBUG2 |
| 602 | DebugSort((Pof) ? 1 : 4, Nitem, Pex, NULL, NULL); |
| 603 | #endif |
| 604 | #endif |
| 605 | |
| 606 | if (Thresh > 2) { |
| 607 | if (Pof) |
| 608 | /*****************************************************************/ |
| 609 | /* The preliminary search for the smallest element has been */ |
| 610 | /* removed so with no sentinel in place, we must check for x */ |
| 611 | /* going below the Pof pointer. For each remaining element */ |
| 612 | /* group from [1] to [n-1], set hi to the index of the element */ |
| 613 | /* AFTER which this one goes. Then, do the standard insertion */ |
| 614 | /* sort shift on an integer at a time basis for each equal */ |
| 615 | /* element group in the frob. */ |
| 616 | /*****************************************************************/ |
| 617 | for (min = hi = 0; min < Nitem; min = hi) { |
| 618 | if (Pof[hi]) { |
| 619 | hi += Pof[hi]; |
| 620 | continue; |
| 621 | } // endif |
| 622 | |
| 623 | Pof[min] = 1; |
| 624 | |
| 625 | #ifdef DEBUG2 |
| 626 | htrc("insert from min=%d\n" , min); |
| 627 | #endif |
| 628 | |
| 629 | for (lo = hi; !Pof[++hi]; lo = hi) { |
| 630 | while (lo >= min && (rc = Qcompare(Pex + lo, Pex + hi)) > 0) |
| 631 | if (Pof[lo] > 0) |
| 632 | lo -= Pof[lo]; |
| 633 | else |
| 634 | return -2; |
| 635 | |
| 636 | if (++lo != hi) { |
| 637 | c = Pex[hi]; |
| 638 | |
| 639 | for (i = j = hi; i > 0; i = j) |
| 640 | if (Pof[i - 1] <= 0) |
| 641 | return -3; |
| 642 | else if ((j -= Pof[i - 1]) >= lo) { |
| 643 | for (k = m = i; --m >= j; k--) // Move intermediate |
| 644 | Pex[k] = Pex[m]; // for conservation. |
| 645 | |
| 646 | Pof[j + 1] = Pof[i] = Pof[j]; |
| 647 | } else |
| 648 | break; |
| 649 | |
| 650 | Pex[i] = c; |
| 651 | } // endif |
| 652 | |
| 653 | if (rc) |
| 654 | Pof[lo] = 1; |
| 655 | else { |
| 656 | i = lo - Pof[lo - 1]; |
| 657 | Pof[lo] = ++Pof[i]; |
| 658 | } // endelse |
| 659 | |
| 660 | #ifdef DEBUG2 |
| 661 | htrc("rc=%d lo=%d hi=%d ofx=%d\n" , rc, lo, hi, Pof[lo]); |
| 662 | #endif |
| 663 | |
| 664 | } // endfor hi |
| 665 | |
| 666 | } // endfor min |
| 667 | |
| 668 | else |
| 669 | /*****************************************************************/ |
| 670 | /* Call conservative insertion sort not using/setting offset. */ |
| 671 | /*****************************************************************/ |
| 672 | Istc(Pex, Pex + MY_MIN(Nitem, Thresh), max); |
| 673 | |
| 674 | } // endif Thresh |
| 675 | |
| 676 | #ifdef DEBTRACE |
| 677 | htrc(" after insert sort num_comp=%d\n" , num_comp); |
| 678 | num_comp += ncp; |
| 679 | #endif |
| 680 | |
| 681 | if (Pof) |
| 682 | /*******************************************************************/ |
| 683 | /* Reduce the Offset array. */ |
| 684 | /*******************************************************************/ |
| 685 | for (i = j = 0; i <= Nitem; j++, i += c) { |
| 686 | #ifdef DEBUG2 |
| 687 | htrc(" Pof(%d)=%d Pof(%d)=%d c=%d\n" , |
| 688 | i, Pof[i], j, Pof[j], c); |
| 689 | #endif |
| 690 | if ((c = Pof[i])) |
| 691 | Pof[j] = i; |
| 692 | else |
| 693 | return -4; |
| 694 | |
| 695 | } // endfor i |
| 696 | |
| 697 | return (j - 1); |
| 698 | } // end of Qsortc |
| 699 | |
| 700 | /***********************************************************************/ |
| 701 | /* Qstc: Do a quicksort on index elements (just one int int). */ |
| 702 | /* First, find the median element, and set it as the discriminator. */ |
| 703 | /* (This "median" is just the median of the first, last and middle */ |
| 704 | /* elements). (Using this median instead of the first element is a */ |
| 705 | /* big win). Then, the special partitioning/swapping, where elements */ |
| 706 | /* smaller than the discriminator are placed in the sorted block, */ |
| 707 | /* elements equal to the discriminator are placed backward from the */ |
| 708 | /* top of the work area and elements greater than *j (discriminator) */ |
| 709 | /* are placed in the work area from its bottom. Then the elements in */ |
| 710 | /* the work area are placed back in the sort area in natural order, */ |
| 711 | /* making the sort conservative. Non equal blocks shrink faster when */ |
| 712 | /* equal elements exist. This is a huge win in case of repartitions */ |
| 713 | /* with few different elements. The mid block being at its final */ |
| 714 | /* position, its first and last elements are marked in the offset */ |
| 715 | /* list (used to make break list). Then, figure out the sizes of the */ |
| 716 | /* two partitions, do the smaller one recursively and the larger one */ |
| 717 | /* via a repeat of this code. Stopping when there are less than */ |
| 718 | /* THRESH elements in a partition and cleaning up with an insertion */ |
| 719 | /* sort (in our caller) is a huge win (yet to be proved?). */ |
| 720 | /***********************************************************************/ |
| 721 | void CSORT::Qstc(int *base, int *max) |
| 722 | { |
| 723 | register int *i, *j, *jj, *lt, *eq, *gt, *mid; |
| 724 | int c = 0, lo, hi, rc; |
| 725 | size_t zlo, zhi, cnm; |
| 726 | |
| 727 | zlo = zhi = cnm = 0; // Avoid warning message |
| 728 | |
| 729 | lo = (int)(max - base); // Number of elements as longs |
| 730 | |
| 731 | if (Dup) |
| 732 | cnm = Cmpnum(lo); |
| 733 | |
| 734 | do { |
| 735 | /*******************************************************************/ |
| 736 | /* At the top here, lo is the number of integers of elements in */ |
| 737 | /* the current partition. (Which should be max - base). Find the */ |
| 738 | /* median of the first, last, and middle element and make that */ |
| 739 | /* the compare element. Set jj to smallest of middle and last. */ |
| 740 | /* If base is smaller or equal than that guy, then it's that guy, */ |
| 741 | /* else compare base with loser of first and take smaller. Things */ |
| 742 | /* are set up to prefer the top, then the middle in case of ties. */ |
| 743 | /*******************************************************************/ |
| 744 | i = base + (lo >> 1); |
| 745 | jj = mid = max - 1; |
| 746 | |
| 747 | #ifdef DEBTRACE |
| 748 | htrc("--> block base=%d size=%d\n" , base - Pex, lo); |
| 749 | DebugSort(2, 0, base, i, mid); |
| 750 | #endif |
| 751 | |
| 752 | if (lo >= Mthresh) { |
| 753 | jj = ((rc = Qcompare(i, mid)) < 0) ? i : mid; |
| 754 | |
| 755 | if (rc && Qcompare(base, jj) > 0) { |
| 756 | jj = (jj == mid) ? i : mid; // switch to first loser |
| 757 | |
| 758 | if (Qcompare(base, jj) < 0) |
| 759 | jj = base; |
| 760 | |
| 761 | } // endif |
| 762 | |
| 763 | if (jj != mid) { |
| 764 | /***************************************************************/ |
| 765 | /* The compare element must be at the top of the block so it */ |
| 766 | /* cannot be overwritten while making the partitioning. So */ |
| 767 | /* save the last block value which will be compared later. */ |
| 768 | /***************************************************************/ |
| 769 | c = *mid; |
| 770 | *mid = *jj; |
| 771 | } // endif |
| 772 | |
| 773 | } else if (lo == 2) { |
| 774 | /*****************************************************************/ |
| 775 | /* Small group. Do special quicker processing. */ |
| 776 | /*****************************************************************/ |
| 777 | if ((rc = Qcompare(base, (i = base + 1))) > 0) { |
| 778 | c = *base; |
| 779 | *base = *i; |
| 780 | *i = c; |
| 781 | } // endif rc |
| 782 | |
| 783 | if (Pof) |
| 784 | Pof[base - Pex] = Pof[i - Pex] = (rc) ? 1 : 2; |
| 785 | |
| 786 | break; |
| 787 | } // endif lo |
| 788 | |
| 789 | #ifdef DEBTRACE |
| 790 | DebugSort(3, lo, NULL, jj, &rc); |
| 791 | #endif |
| 792 | |
| 793 | /*******************************************************************/ |
| 794 | /* Non-standard quicksort partitioning using additional storage */ |
| 795 | /* to store values less than, equal or greater than the middle */ |
| 796 | /* element. This uses more memory but provides conservation of */ |
| 797 | /* the equal elements order. */ |
| 798 | /*******************************************************************/ |
| 799 | lt = base; |
| 800 | eq = Swix + lo; |
| 801 | gt = Swix; |
| 802 | |
| 803 | if (jj == mid) { |
| 804 | /*****************************************************************/ |
| 805 | /* Compare element was last. No problem. */ |
| 806 | /*****************************************************************/ |
| 807 | for (i = base; i < max; i++) |
| 808 | if ((rc = Qcompare(i, mid)) < 0) |
| 809 | *lt++ = *i; |
| 810 | else if (rc > 0) |
| 811 | *gt++ = *i; |
| 812 | else |
| 813 | *--eq = *i; |
| 814 | |
| 815 | } else { |
| 816 | /*****************************************************************/ |
| 817 | /* Compare element was not last and was copied to top of block. */ |
| 818 | /*****************************************************************/ |
| 819 | for (i = base; i < mid; i++) |
| 820 | if ((rc = Qcompare(i, mid)) < 0) |
| 821 | *lt++ = *i; |
| 822 | else if (rc > 0) |
| 823 | *gt++ = *i; |
| 824 | else |
| 825 | *--eq = *i; |
| 826 | |
| 827 | /*****************************************************************/ |
| 828 | /* Restore saved last value and do the comparison from there. */ |
| 829 | /*****************************************************************/ |
| 830 | *--i = c; |
| 831 | |
| 832 | if ((rc = Qcompare(i, mid)) < 0) |
| 833 | *lt++ = *i; |
| 834 | else if (rc > 0) |
| 835 | *gt++ = *i; |
| 836 | else |
| 837 | *--eq = *i; |
| 838 | |
| 839 | } // endif |
| 840 | |
| 841 | /*******************************************************************/ |
| 842 | /* Now copy the equal and greater values back in the main array in */ |
| 843 | /* the same order they have been placed in the work area. */ |
| 844 | /*******************************************************************/ |
| 845 | for (j = Swix + lo, i = lt; j > eq; ) |
| 846 | *i++ = *--j; |
| 847 | |
| 848 | for (j = Swix, jj = i; j < gt; ) |
| 849 | *i++ = *j++; |
| 850 | |
| 851 | /*******************************************************************/ |
| 852 | /* The mid block being placed at its final position we can now set */ |
| 853 | /* the offset array values indicating break point and block size. */ |
| 854 | /*******************************************************************/ |
| 855 | if (Pof) |
| 856 | Pof[lt - Pex] = Pof[(jj - 1) - Pex] = (int)(jj - lt); |
| 857 | |
| 858 | /*******************************************************************/ |
| 859 | /* Look at sizes of the two partitions, do the smaller one first */ |
| 860 | /* by recursion, then do the larger one by making sure lo is its */ |
| 861 | /* size, base and max are update correctly, and branching back. */ |
| 862 | /* But only repeat (recursively or by branching) if the partition */ |
| 863 | /* is of at least size THRESH. */ |
| 864 | /*******************************************************************/ |
| 865 | lo = (int)(lt - base); |
| 866 | hi = (int)(gt - Swix); |
| 867 | |
| 868 | if (Dup) { // Update progress information |
| 869 | zlo = Cmpnum(lo); |
| 870 | zhi = Cmpnum(hi); |
| 871 | Dup->ProgCur += cnm - (zlo + zhi); |
| 872 | } // endif Dup |
| 873 | |
| 874 | #ifdef DEBTRACE |
| 875 | htrc(" done lo=%d hi=%d\n" , |
| 876 | lo, /*Swix + lt - base - eq,*/ hi); |
| 877 | #endif |
| 878 | |
| 879 | if (lo <= hi) { |
| 880 | if (lo >= Thresh) |
| 881 | Qstc(base, lt); |
| 882 | else if (lo == 1 && Pof) |
| 883 | Pof[base - Pex] = 1; |
| 884 | |
| 885 | base = jj; |
| 886 | lo = hi; |
| 887 | cnm = zhi; |
| 888 | } else { |
| 889 | if (hi >= Thresh) |
| 890 | Qstc(jj, max); |
| 891 | else if (hi == 1 && Pof) |
| 892 | Pof[jj - Pex] = 1; |
| 893 | |
| 894 | max = lt; |
| 895 | cnm = zlo; |
| 896 | } // endif |
| 897 | |
| 898 | if (lo == 1 && Pof) |
| 899 | Pof[base - Pex] = 1; |
| 900 | |
| 901 | } while (lo >= Thresh); // enddo |
| 902 | |
| 903 | } // end of Qstc |
| 904 | |
| 905 | /***********************************************************************/ |
| 906 | /* Conservative insertion sort not using/setting offset array. */ |
| 907 | /***********************************************************************/ |
| 908 | void CSORT::Istc(int *base, int *hi, int *max) |
| 909 | { |
| 910 | register int c = 0; |
| 911 | register int *lo; |
| 912 | register int *i, *j; |
| 913 | |
| 914 | /*********************************************************************/ |
| 915 | /* First put smallest element, which must be in the first THRESH, */ |
| 916 | /* in the first position as a sentinel. This is done just by */ |
| 917 | /* searching the 1st THRESH elements (or the 1st n if n < THRESH) */ |
| 918 | /* finding the min, and shifting it into the first position. */ |
| 919 | /*********************************************************************/ |
| 920 | for (j = lo = base; ++lo < hi; ) |
| 921 | if (Qcompare(j, lo) > 0) |
| 922 | j = lo; |
| 923 | |
| 924 | if (j != base) { // shift j into place |
| 925 | c = *j; |
| 926 | |
| 927 | for (i = j; --j >= base; i = j) |
| 928 | *i = *j; |
| 929 | |
| 930 | *base = c; |
| 931 | } // endif j |
| 932 | |
| 933 | #ifdef DEBTRACE |
| 934 | htrc("sentinel %d in place, base=%p hi=%p max=%p\n" , |
| 935 | c, base, hi, max); |
| 936 | #endif |
| 937 | |
| 938 | /*********************************************************************/ |
| 939 | /* With our sentinel in place, we now run the following hyper- */ |
| 940 | /* fast insertion sort. For each remaining element, lo, from [1] */ |
| 941 | /* to [n-1], set hi to the index of the element AFTER which this */ |
| 942 | /* one goes. Then, do the standard insertion sort shift for each */ |
| 943 | /* element in the frob. */ |
| 944 | /*********************************************************************/ |
| 945 | for (lo = base; (hi = ++lo) < max;) { |
| 946 | while (Qcompare(--hi, lo) > 0) ; |
| 947 | |
| 948 | #ifdef DEBUG2 |
| 949 | htrc("after while: hi(%p)=%d lo(%p)=%d\n" , |
| 950 | hi, *hi, lo, *lo); |
| 951 | #endif |
| 952 | |
| 953 | if (++hi != lo) { |
| 954 | c = *lo; |
| 955 | |
| 956 | for (i = j = lo; --j >= hi; i = j) |
| 957 | *i = *j; |
| 958 | |
| 959 | *i = c; |
| 960 | } // endif hi |
| 961 | |
| 962 | } // endfor lo |
| 963 | |
| 964 | } // end of Istc |
| 965 | |
| 966 | /* -------------------------- End of CSort --------------------------- */ |
| 967 | |