[13] | 1 | /* Record manager routines */ |
---|
| 2 | |
---|
| 3 | |
---|
| 4 | #include "memint.h" |
---|
| 5 | |
---|
| 6 | |
---|
| 7 | #define ALLOC_SIZE NICE_BLOCK_SIZE |
---|
| 8 | |
---|
| 9 | |
---|
| 10 | /* #define DEBUG_MEM */ |
---|
| 11 | #define MAGIC_COOKIE 0x34f21ab3l |
---|
| 12 | #define MAGIC_COOKIE1 0x432fa13bl |
---|
| 13 | |
---|
| 14 | |
---|
| 15 | struct list_ |
---|
| 16 | { |
---|
| 17 | struct list_ *next; |
---|
| 18 | }; |
---|
| 19 | |
---|
| 20 | typedef struct list_ *list; |
---|
| 21 | |
---|
| 22 | |
---|
| 23 | struct rec_mgr_ |
---|
| 24 | { |
---|
| 25 | int size; |
---|
| 26 | int recs_per_block; |
---|
| 27 | list free; |
---|
| 28 | list blocks; |
---|
| 29 | }; |
---|
| 30 | |
---|
| 31 | |
---|
| 32 | /* mem_new_rec(mgr) allocates a record from the specified record */ |
---|
| 33 | /* manager. */ |
---|
| 34 | |
---|
| 35 | pointer |
---|
| 36 | #if defined(__STDC__) |
---|
| 37 | mem_new_rec(rec_mgr mgr) |
---|
| 38 | #else |
---|
| 39 | mem_new_rec(mgr) |
---|
| 40 | rec_mgr mgr; |
---|
| 41 | #endif |
---|
| 42 | { |
---|
| 43 | int i; |
---|
| 44 | pointer p; |
---|
| 45 | list new_; |
---|
| 46 | |
---|
| 47 | if (!mgr->free) |
---|
| 48 | { |
---|
| 49 | /* Allocate a new block. */ |
---|
| 50 | new_=(list)mem_get_block(ALLOC_SIZE); |
---|
| 51 | new_->next=mgr->blocks; |
---|
| 52 | mgr->blocks=new_; |
---|
| 53 | mgr->free=(list)((INT_PTR)new_+ROUNDUP(sizeof(struct list_))); |
---|
| 54 | p=(pointer)(mgr->free); |
---|
| 55 | /* Carve the block into pieces. */ |
---|
| 56 | for (i=1; i < mgr->recs_per_block; ++i) |
---|
| 57 | { |
---|
| 58 | ((list)p)->next=(list)((INT_PTR)p+mgr->size); |
---|
| 59 | #if defined(DEBUG_MEM) |
---|
| 60 | if (mgr->size >= sizeof(long)+sizeof(struct list_)) |
---|
| 61 | *(long *)(sizeof(struct list_)+(INT_PTR)p)=MAGIC_COOKIE; |
---|
| 62 | #endif |
---|
| 63 | p=(pointer)((INT_PTR)p+mgr->size); |
---|
| 64 | } |
---|
| 65 | ((list)p)->next=0; |
---|
| 66 | #if defined(DEBUG_MEM) |
---|
| 67 | if (mgr->size >= sizeof(long)+sizeof(struct list_)) |
---|
| 68 | *(long *)(sizeof(struct list_)+(INT_PTR)p)=MAGIC_COOKIE; |
---|
| 69 | #endif |
---|
| 70 | } |
---|
| 71 | new_=mgr->free; |
---|
| 72 | #if defined(DEBUG_MEM) |
---|
| 73 | if (mgr->size >= sizeof(long)+sizeof(struct list_)) |
---|
| 74 | if (*(long *)(sizeof(struct list_)+(INT_PTR)new_) != MAGIC_COOKIE) |
---|
| 75 | fprintf(stderr, "record at 0x%lx may be in use\n", (INT_PTR)new_); |
---|
| 76 | else |
---|
| 77 | *(long *)(sizeof(struct list_)+(INT_PTR)new_)=MAGIC_COOKIE1; |
---|
| 78 | #endif |
---|
| 79 | mgr->free=mgr->free->next; |
---|
| 80 | return ((pointer)new_); |
---|
| 81 | } |
---|
| 82 | |
---|
| 83 | |
---|
| 84 | /* mem_free_rec(mgr, rec) frees a record managed by the indicated */ |
---|
| 85 | /* record manager. */ |
---|
| 86 | |
---|
| 87 | void |
---|
| 88 | #if defined(__STDC__) |
---|
| 89 | mem_free_rec(rec_mgr mgr, pointer rec) |
---|
| 90 | #else |
---|
| 91 | mem_free_rec(mgr, rec) |
---|
| 92 | rec_mgr mgr; |
---|
| 93 | pointer rec; |
---|
| 94 | #endif |
---|
| 95 | { |
---|
| 96 | #if defined(DEBUG_MEM) |
---|
| 97 | if (mgr->size >= sizeof(long)+sizeof(struct list_)) |
---|
| 98 | if (*(long *)(sizeof(struct list_)+(INT_PTR)rec) == MAGIC_COOKIE) |
---|
| 99 | fprintf(stderr, "record at 0x%lx may already be freed\n", (INT_PTR)rec); |
---|
| 100 | #endif |
---|
| 101 | ((list)rec)->next=mgr->free; |
---|
| 102 | #if defined(DEBUG_MEM) |
---|
| 103 | if (mgr->size >= sizeof(long)+sizeof(struct list_)) |
---|
| 104 | *(long *)(sizeof(struct list_)+(INT_PTR)rec)=MAGIC_COOKIE; |
---|
| 105 | #endif |
---|
| 106 | mgr->free=(list)rec; |
---|
| 107 | } |
---|
| 108 | |
---|
| 109 | |
---|
| 110 | /* mem_new_rec_mgr(size) creates a new record manager with the given */ |
---|
| 111 | /* record size. */ |
---|
| 112 | |
---|
| 113 | rec_mgr |
---|
| 114 | #if defined(__STDC__) |
---|
| 115 | mem_new_rec_mgr(int size) |
---|
| 116 | #else |
---|
| 117 | mem_new_rec_mgr(size) |
---|
| 118 | int size; |
---|
| 119 | #endif |
---|
| 120 | { |
---|
| 121 | rec_mgr mgr; |
---|
| 122 | |
---|
| 123 | if (size < sizeof(struct list_)) |
---|
| 124 | size=sizeof(struct list_); |
---|
| 125 | size=ROUNDUP(size); |
---|
| 126 | if (size > ALLOC_SIZE-ROUNDUP(sizeof(struct list_))) |
---|
| 127 | mem_fatal("mem_new_rec_mgr: record size too large"); |
---|
| 128 | mgr=(rec_mgr)mem_get_block((SIZE_T)sizeof(struct rec_mgr_)); |
---|
| 129 | mgr->size=size; |
---|
| 130 | mgr->recs_per_block=(ALLOC_SIZE-ROUNDUP(sizeof(struct list_)))/size; |
---|
| 131 | mgr->free=0; |
---|
| 132 | mgr->blocks=0; |
---|
| 133 | return (mgr); |
---|
| 134 | } |
---|
| 135 | |
---|
| 136 | |
---|
| 137 | /* mem_free_rec_mgr(mgr) frees all the storage associated with the */ |
---|
| 138 | /* specified record manager. */ |
---|
| 139 | |
---|
| 140 | void |
---|
| 141 | #if defined(__STDC__) |
---|
| 142 | mem_free_rec_mgr(rec_mgr mgr) |
---|
| 143 | #else |
---|
| 144 | mem_free_rec_mgr(mgr) |
---|
| 145 | rec_mgr mgr; |
---|
| 146 | #endif |
---|
| 147 | { |
---|
| 148 | list p, q; |
---|
| 149 | |
---|
| 150 | for (p=mgr->blocks; p; p=q) |
---|
| 151 | { |
---|
| 152 | q=p->next; |
---|
| 153 | mem_free_block((pointer)p); |
---|
| 154 | } |
---|
| 155 | mem_free_block((pointer)mgr); |
---|
| 156 | } |
---|