unarray.d

   1 /*
   2  * coded by Ketmar // Invisible Vector <ketmar@ketmar.no-ip.org>
   3  * Understanding is not required. Only obedience.
   4  *
   5  * This program is free software: you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation, version 3 of the License ONLY.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  16  */
  17 // some "unsafe" array operations
  18 // such arrays should be always anchored to first element
  19 module iv.unarray /*is aliced*/;
  20 import iv.alice;
  21
  22
  23 // ////////////////////////////////////////////////////////////////////////// //
  24 public void unsafeArrayReserve(T) (ref T[] arr, usize newlen) /*nothrow*/ {
  25   if (/*newlen < 0 ||*/ newlen >= int.max/2) assert(0, "invalid number of elements in array");
  26   if (arr.length < newlen) {
  27     auto optr = arr.ptr;
  28     arr.reserve(newlen);
  29     if (arr.ptr !is optr) {
  30       import core.memory : GC;
  31       optr = arr.ptr;
  32       if (optr is GC.addrOf(optr)) GC.setAttr(optr, GC.BlkAttr.NO_INTERIOR);
  33     }
  34   }
  35 }
  36
  37
  38 public void unsafeArraySetLength(T) (ref T[] arr, usize newlen) /*nothrow*/ {
  39   if (/*newlen < 0 ||*/ newlen >= int.max/2) assert(0, "invalid number of elements in array");
  40   if (arr.length > newlen) {
  41     arr.length = newlen;
  42     arr.assumeSafeAppend;
  43   } else if (arr.length < newlen) {
  44     auto optr = arr.ptr;
  45     arr.length = newlen;
  46     if (arr.ptr !is optr) {
  47       import core.memory : GC;
  48       optr = arr.ptr;
  49       if (optr is GC.addrOf(optr)) GC.setAttr(optr, GC.BlkAttr.NO_INTERIOR);
  50     }
  51   }
  52 }
  53
  54
  55 public void unsafeArrayAppend(T) (ref T[] arr, auto ref T v) /*nothrow*/ {
  56   if (arr.length >= int.max/2) assert(0, "too many elements in array");
  57   auto optr = arr.ptr;
  58   arr ~= v;
  59   if (arr.ptr !is optr) {
  60     import core.memory : GC;
  61     optr = arr.ptr;
  62     if (optr is GC.addrOf(optr)) GC.setAttr(optr, GC.BlkAttr.NO_INTERIOR);
  63   }
  64 }
  65
  66
  67 public void unsafeArrayClear(T) (ref T[] arr) /*nothrow*/ {
  68   if (arr.length) {
  69     import core.stdc.string : memset;
  70     static if (is(T == class)) arr[] = null; /*else arr[] = T.init;*/
  71     memset(arr.ptr, 0, arr.length*T.sizeof);
  72     arr.length = 0;
  73     arr.assumeSafeAppend;
  74   }
  75 }
  76
  77
  78 public void unsafeArrayRemove(T) (ref T[] arr, usize idx) /*nothrow*/ {
  79   if (/*idx < 0 ||*/ idx >= arr.length) assert(0, "invalid index in `unsafeArrayRemove()`");
  80   static if (is(T == class)) arr[idx] = null; else arr[idx] = T.init;
  81   if (arr.length-idx > 1) {
  82     import core.stdc.string : memset, memmove;
  83     memmove(arr.ptr+idx, arr.ptr+idx+1, (arr.length-idx-1)*T.sizeof);
  84     memset(arr.ptr+arr.length-1, 0, T.sizeof);
  85   }
  86   arr.length -= 1;
  87   arr.assumeSafeAppend;
  88 }
  89
  90
  91 public void unsafeArrayInsertBefore(T) (ref T[] arr, usize idx, auto ref T v) /*nothrow*/ {
  92   if (/*idx < 0 ||*/ idx > arr.length) assert(0, "invalid index in `unsafeArrayRemove()`");
  93   auto olen = cast(int)arr.length;
  94   if (olen >= int.max/2) assert(0, "too many elements in array");
  95   auto optr = arr.ptr;
  96   arr.length += 1;
  97   if (arr.ptr != optr) {
  98     import core.memory : GC;
  99     optr = arr.ptr;
 100     if (optr is GC.addrOf(optr)) GC.setAttr(optr, GC.BlkAttr.NO_INTERIOR);
 101   }
 102   // move elements down
 103   if (idx < olen) {
 104     import core.stdc.string : memset, memmove;
 105     memmove(arr.ptr+idx+1, arr.ptr+idx, (olen-idx)*T.sizeof);
 106     memset(arr.ptr+idx, 0, T.sizeof);
 107   }
 108   arr[idx] = v;
 109 }