Re: [PATCH 09/11] sandbox: Add a way to map a file into memory

On Wed, 18 Aug 2021 21:40:31 -0600 Simon Glass sjg@chromium.org wrote:

It is useful to map a file into memory so that it can be accessed using simple pointers. Add a function to support this.

Signed-off-by: Simon Glass sjg@chromium.org

+int os_map_file(const char *pathname, int os_flags, void **bufp, int *sizep) +{

• void *ptr;
• int size;
• int ifd;
• ifd = os_open(pathname, os_flags);
• if (ifd < 0) {

• printf("Cannot open file '%s'\n", pathname);
  

• return -EIO;
  

• }
• size = os_filesize(ifd);
• if (size < 0) {

• printf("Cannot get file size of '%s'\n", pathname);
  

• return -EIO;
  

• }
• ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, ifd, 0);
• if (ptr == MAP_FAILED) {

• printf("Can't map file '%s': %s\n", pathname, strerror(errno));
  

• return -EPERM;
  

• }
• *bufp = ptr;
• *sizep = size;
• return 0;

+}

You need to close the file descriptor after mmapping.

Marek