projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| d99e8b3c KT |
1 | # |
| 2 | /* | |
| 3 | */ | |
| 4 | ||
| 5 | /* | |
| 6 | * Structure of the coremap and swapmap | |
| 7 | * arrays. Consists of non-zero count | |
| 8 | * and base address of that many | |
| 9 | * contiguous units. | |
| 10 | * (The coremap unit is 64 bytes, | |
| 11 | * the swapmap unit is 512 bytes) | |
| 12 | * The addresses are increasing and | |
| 13 | * the list is terminated with the | |
| 14 | * first zero count. | |
| 15 | */ | |
| 16 | struct map | |
| 17 | { | |
| 18 | char *m_size; | |
| 19 | char *m_addr; | |
| 20 | }; | |
| 21 | ||
| 22 | /* | |
| 23 | * Allocate size units from the given | |
| 24 | * map. Return the base of the allocated | |
| 25 | * space. | |
| 26 | * Algorithm is first fit. | |
| 27 | */ | |
| 28 | malloc(mp, size) | |
| 29 | struct map *mp; | |
| 30 | { | |
| 31 | register int a; | |
| 32 | register struct map *bp; | |
| 33 | ||
| 34 | for (bp = mp; bp->m_size; bp++) { | |
| 35 | if (bp->m_size >= size) { | |
| 36 | a = bp->m_addr; | |
| 37 | bp->m_addr =+ size; | |
| 38 | if ((bp->m_size =- size) == 0) | |
| 39 | do { | |
| 40 | bp++; | |
| 41 | (bp-1)->m_addr = bp->m_addr; | |
| 42 | } while ((bp-1)->m_size = bp->m_size); | |
| 43 | return(a); | |
| 44 | } | |
| 45 | } | |
| 46 | return(0); | |
| 47 | } | |
| 48 | ||
| 49 | /* | |
| 50 | * Free the previously allocated space aa | |
| 51 | * of size units into the specified map. | |
| 52 | * Sort aa into map and combine on | |
| 53 | * one or both ends if possible. | |
| 54 | */ | |
| 55 | mfree(mp, size, aa) | |
| 56 | struct map *mp; | |
| 57 | { | |
| 58 | register struct map *bp; | |
| 59 | register int t; | |
| 60 | register int a; | |
| 61 | ||
| 62 | a = aa; | |
| 63 | for (bp = mp; bp->m_addr<=a && bp->m_size!=0; bp++); | |
| 64 | if (bp>mp && (bp-1)->m_addr+(bp-1)->m_size == a) { | |
| 65 | (bp-1)->m_size =+ size; | |
| 66 | if (a+size == bp->m_addr) { | |
| 67 | (bp-1)->m_size =+ bp->m_size; | |
| 68 | while (bp->m_size) { | |
| 69 | bp++; | |
| 70 | (bp-1)->m_addr = bp->m_addr; | |
| 71 | (bp-1)->m_size = bp->m_size; | |
| 72 | } | |
| 73 | } | |
| 74 | } else { | |
| 75 | if (a+size == bp->m_addr && bp->m_size) { | |
| 76 | bp->m_addr =- size; | |
| 77 | bp->m_size =+ size; | |
| 78 | } else if (size) do { | |
| 79 | t = bp->m_addr; | |
| 80 | bp->m_addr = a; | |
| 81 | a = t; | |
| 82 | t = bp->m_size; | |
| 83 | bp->m_size = size; | |
| 84 | bp++; | |
| 85 | } while (size = t); | |
| 86 | } | |
| 87 | } |