BSD 4_4_Lite2 development

[unix-history] / usr / src / contrib / nvi.1.43 / PORT / isc.3 / local / mmap.c

#include <sys/types.h>

#include <stdlib.h>

#include "compat.h"

/*
* This function emulates mmap() by reading `len' bytes from the file
* descriptor `fd' and returning a pointer to that memory.  The "mapped"
* region can later be deallocated with munmap().
*
* Note: ONLY reading is supported and only reading of the exact size
* of the file will work.
*/
char *
mmap_hack(addr, len, prot, flags, fd, off)
       char *addr;
       size_t len;
       int prot;
       int flags;
       int fd;
       off_t off;
{
       char *ptr;

       if ((ptr = (char *)malloc(len)) == 0)
               return (-1);
       if (read(fd, ptr, len) < 0) {
               free(ptr);
               return (-1);
       }
       return (ptr);
}

int
munmap_hack(addr, len)
       char *addr;
       size_t len;
{
       free(addr);
       return (0);
}