#include "../hd/param.h" #include "../hd/systm.h" /* * Allocate 'size' units from the given * map. Return the base of the allocated * space. * In a map, the addresses are increasing and the * list is terminated by a 0 size. * The core map unit is 64 bytes; the swap map unit * is 512 bytes. * Algorithm is first-fit. */ malloc(mp, size) struct map *mp; { register int a; register struct map *bp; for (bp=mp; bp->m_size; bp++) { if (bp->m_size >= size) { a = bp->m_addr; bp->m_addr =+ size; if ((bp->m_size =- size) == 0) do { bp++; (bp-1)->m_addr = bp->m_addr; } while ((bp-1)->m_size = bp->m_size); return(a); } } return(0); } /* * Free the previously allocated space aa * of size units into the specified map. * Sort aa into map and combine on * one or both ends if possible. */ mfree(mp, size, aa) struct map *mp; char *aa; { register struct map *bp; register int t; register char *a; a = aa; if ((bp = mp)==coremap && runin) { runin = 0; wakeup(&runin); /* Wake scheduler when freeing core */ } for (; bp->m_addr<=a && bp->m_size!=0; bp++); if (bp>mp && (bp-1)->m_addr+(bp-1)->m_size == a) { (bp-1)->m_size =+ size; if (a+size == bp->m_addr) { (bp-1)->m_size =+ bp->m_size; while (bp->m_size) { bp++; (bp-1)->m_addr = bp->m_addr; (bp-1)->m_size = bp->m_size; } } } else { if (a+size == bp->m_addr && bp->m_size) { bp->m_addr =- size; bp->m_size =+ size; } else if (size) do { t = bp->m_addr; bp->m_addr = a; a = t; t = bp->m_size; bp->m_size = size; bp++; } while (size = t); } }