| 1 | # |
| 2 | /* |
| 3 | * C library -- alloc/free |
| 4 | */ |
| 5 | |
| 6 | #define logical int |
| 7 | |
| 8 | struct fb { |
| 9 | logical size; |
| 10 | char *next; |
| 11 | }; |
| 12 | |
| 13 | int freelist[] = { |
| 14 | 0, |
| 15 | -1, |
| 16 | }; |
| 17 | logical slop = 2; |
| 18 | |
| 19 | alloc(asize) |
| 20 | logical asize; |
| 21 | { return ( calloc ( 1 , asize ) ); } |
| 22 | /*{ |
| 23 | register logical size; |
| 24 | register logical np; |
| 25 | register logical cp; |
| 26 | |
| 27 | if ((size = asize) == 0) |
| 28 | return(0); |
| 29 | size += 3; |
| 30 | size &= ~01; |
| 31 | for (;;) { |
| 32 | cp = freelist; |
| 33 | while ((np = cp->next) != -1) { |
| 34 | if (np->size>=size) { |
| 35 | if (size+slop >= np->size) { |
| 36 | cp->next = np->next; |
| 37 | return(&np->next); |
| 38 | } |
| 39 | cp = cp->next = np+size; |
| 40 | cp->size = np->size - size; |
| 41 | cp->next = np->next; |
| 42 | np->size = size; |
| 43 | return(&np->next); |
| 44 | } |
| 45 | cp = np; |
| 46 | } |
| 47 | return ( calloc ( 1 , asize ) ); |
| 48 | |
| 49 | /* asize = size<1024? 1024: size; |
| 50 | if ((cp = sbrk(asize)) == -1) { |
| 51 | error("workspace exceeded"); |
| 52 | |
| 53 | } |
| 54 | cp->size = asize; |
| 55 | free(&cp->next); |
| 56 | } |
| 57 | } */ |
| 58 | |
| 59 | |
| 60 | afree(aptr) |
| 61 | char *aptr; |
| 62 | {if ( aptr == 0 ) return; |
| 63 | cfree ( aptr ); } |
| 64 | /* { |
| 65 | register logical ptr; |
| 66 | register logical cp; |
| 67 | register logical np; |
| 68 | |
| 69 | if (aptr == 0) return; |
| 70 | ptr = aptr-4; |
| 71 | cp = freelist; |
| 72 | while ((np = cp->next) < ptr) |
| 73 | cp = np; |
| 74 | if (ptr+ptr->size == np) { |
| 75 | ptr->size += np->size; |
| 76 | ptr->next = np->next; |
| 77 | np = ptr; |
| 78 | } else |
| 79 | ptr->next = np; |
| 80 | if (cp+cp->size == ptr) { |
| 81 | cp->size += ptr->size; |
| 82 | cp->next = ptr->next; |
| 83 | } else |
| 84 | cp->next = ptr; |
| 85 | } */ |