mapping.h

   1 #include <sys/mman.h>
   2
   3 #include <errno.h>
   4 #include <unistd.h>
   5
   6 #include <sys/types.h>
   7 #include <sys/stat.h>
   8 #include <fcntl.h>
   9
  10 void *map(const char *path, size_t offset, size_t size, size_t *psize, bool ro) {
  11     int fd;
  12     _syscall(fd = open(path, ro ? O_RDONLY : O_RDWR));
  13
  14     if (size == _not(size_t)) {
  15         struct stat stat;
  16         _syscall(fstat(fd, &stat));
  17         size = stat.st_size;
  18     }
  19
  20     if (psize != NULL)
  21         *psize = size;
  22
  23     void *base;
  24     _syscall(base = mmap(NULL, size, ro ? PROT_READ : PROT_READ | PROT_WRITE, MAP_SHARED, fd, offset));
  25
  26     _syscall(close(fd));
  27     return base;
  28 }