sysdeps/nacl/open.c

   1
   2 #include <errno.h>
   3 #include <fcntl.h>
   4 #include <stdarg.h>
   5 #include <string.h>
   6 #include <sysdep.h>
   7 #include <unistd.h>
   8
   9 #include <nacl_rpc.h>
  10 #include <nacl_syscalls.h>
  11
  12
  13 static int nacl_open_rpc(const char *filename)
  14 {
  15   struct NaClImcMsgIoVec iov;
  16   struct NaClImcMsgHdr msg;
  17   int filename_len = strlen(filename);
  18   char *msg_data = alloca(4 + filename_len);
  19   memcpy(msg_data, "Open", 4);
  20   memcpy(msg_data + 4, filename, filename_len);
  21   iov.base = msg_data;
  22   iov.length = 4 + filename_len;
  23   msg.iov = &iov;
  24   msg.iov_length = 1;
  25   msg.descv = NULL;
  26   msg.desc_length = 0;
  27   if(imc_sendmsg(NACL_COMMS_FD, &msg, 0) < 0)
  28     return -1;
  29
  30   char buf[4];
  31   int fd;
  32   iov.base = buf;
  33   iov.length = sizeof(buf);
  34   msg.descv = &fd;
  35   msg.desc_length = 1;
  36   int got = imc_recvmsg(NACL_COMMS_FD, &msg, 0);
  37   if(got >= 0 && msg.desc_length == 1)
  38     return fd;
  39   else {
  40     errno = ENOENT;
  41     return -1;
  42   }
  43 }
  44
  45 int __open(const char *filename, int flags, ...)
  46 {
  47   int (*nacl_open)(char const *pathname, int flags, int mode) =
  48     NACL_SYSCALL_ADDR(NACL_sys_open);
  49   int mode = 0;
  50   if(flags & O_CREAT) {
  51     va_list arg;
  52     va_start(arg, flags);
  53     mode = va_arg(arg, int);
  54     va_end(arg);
  55   }
  56
  57   if(nacl_should_use_rpc())
  58     return nacl_open_rpc(filename);
  59
  60   int result = nacl_open(filename, flags, mode);
  61   if (result < 0) {
  62     errno = -result;
  63     return -1;
  64   }
  65   return result;
  66 }
  67 libc_hidden_def (__open)
  68 weak_alias (__open, open)
  69 strong_alias (__open, __libc_open)
  70 strong_alias (__open, __open_nocancel)