1 /*********************************************************************** 2 * * 3 * This software is part of the ast package * 4 * Copyright (c) 1985-2011 AT&T Intellectual Property * 5 * and is licensed under the * 6 * Eclipse Public License, Version 1.0 * 7 * by AT&T Intellectual Property * 8 * * 9 * A copy of the License is available at * 10 * http://www.eclipse.org/org/documents/epl-v10.html * 11 * (with md5 checksum b35adb5213ca9657e911e9befb180842) * 12 * * 13 * Information and Software Systems Research * 14 * AT&T Research * 15 * Florham Park NJ * 16 * * 17 * Glenn Fowler <gsf@research.att.com> * 18 * David Korn <dgk@research.att.com> * 19 * Phong Vo <kpv@research.att.com> * 20 * * 21 ***********************************************************************/ 22 #pragma prototyped 23 /* 24 * standalone mini vmalloc implementation 25 * no resize, no free, no disciplines, no methods 26 */ 27 28 #include <ast.h> 29 #include <vmalloc.h> 30 31 Vmalloc_t* Vmregion; 32 33 Vmalloc_t* 34 _vm_open(void) 35 { 36 Vmalloc_t* vp; 37 38 if (vp = newof(0, Vmalloc_t, 1, 0)) 39 { 40 vp->current = &vp->base; 41 vp->data = vp->current->data; 42 vp->size = sizeof(vp->current->data); 43 } 44 return vp; 45 } 46 47 int 48 _vm_close(register Vmalloc_t* vp) 49 { 50 register Vmchunk_t* cp; 51 register Vmchunk_t* np; 52 53 if (!vp) 54 return -1; 55 np = vp->base.next; 56 while (cp = np) 57 { 58 np = cp->next; 59 free(cp); 60 } 61 free(vp); 62 return 0; 63 } 64 65 void* 66 _vm_resize(register Vmalloc_t* vp, void* o, unsigned long size) 67 { 68 char* p; 69 unsigned long n; 70 unsigned long z; 71 72 z = vp->last; 73 vp->last = size; 74 if (o && size < z) 75 return o; 76 if ((o ? (size - z) : size) > vp->size) 77 { 78 n = (size > sizeof(vp->current->data)) ? (size - sizeof(vp->current->data)) : 0; 79 if (!(vp->current->next = newof(0, Vmchunk_t, 1, n))) 80 return 0; 81 vp->current = vp->current->next; 82 vp->data = vp->current->data; 83 vp->size = n ? 0 : sizeof(vp->current->data); 84 if (o) 85 { 86 memcpy(vp->data, o, z); 87 o = (void*)vp->data; 88 } 89 } 90 else if (o) 91 size -= z; 92 p = vp->data; 93 size = roundof(size, VM_ALIGN); 94 if (size >= vp->size) 95 vp->size = 0; 96 else 97 { 98 vp->size -= size; 99 vp->data += size; 100 } 101 return p; 102 } 103