zircon/third_party/ulib/musl/src/time/__map_file.c

#include <fcntl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <unistd.h>

void* __mmap(void*, size_t, int, int, int, off_t);

const char unsigned* __map_file(const char* pathname, size_t* size) {
  struct stat st;
  const unsigned char* map = MAP_FAILED;
  int fd = open(pathname, O_RDONLY | O_CLOEXEC | O_NONBLOCK);
  if (fd < 0)
    return 0;
  if (!fstat(fd, &st)) {
    map = __mmap(0, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
    *size = st.st_size;
  }
  close(fd);
  return map == MAP_FAILED ? 0 : map;
}