libgloss/arc/hl/hl_lseek.c

   1 /*
   2  * hl_lseek.c -- provide _lseek().
   3  *
   4  * Copyright (c) 2024 Synopsys Inc.
   5  *
   6  * The authors hereby grant permission to use, copy, modify, distribute,
   7  * and license this software and its documentation for any purpose, provided
   8  * that existing copyright notices are retained in all copies and that this
   9  * notice is included verbatim in any distributions. No written agreement,
  10  * license, or royalty fee is required for any of the authorized uses.
  11  * Modifications to this software may be copyrighted by their authors
  12  * and need not follow the licensing terms described here, provided that
  13  * the new terms are clearly indicated on the first page of each file where
  14  * they apply.
  15  *
  16  */
  17
  18 #include <errno.h>
  19 #include <stdint.h>
  20 #include <stddef.h>
  21 #include <sys/types.h>
  22 #include <unistd.h>
  23
  24 #include "hl_toolchain.h"
  25 #include "hl_api.h"
  26
  27
  28 /* Implements HL_SYSCALL_LSEEK.  */
  29 static __always_inline off_t
  30 _hl_lseek (int fd, off_t offset, int whence)
  31 {
  32   ssize_t ret;
  33   int32_t n;
  34   uint32_t host_errno;
  35   volatile __uncached char *p;
  36
  37   p = _hl_message (HL_SYSCALL_LSEEK, "iii:ii",
  38                    (uint32_t) fd,               /* i */
  39                    (uint32_t) offset,           /* i */
  40                    (int32_t) whence,            /* i */
  41                    (uint32_t *) &n,             /* :i */
  42                    (uint32_t *) &host_errno     /* :i */);
  43
  44   if (p == NULL)
  45     {
  46       errno = ETIMEDOUT;
  47       ret = -1;
  48     }
  49   else if (n < 0)
  50     {
  51       errno = host_errno;
  52       ret = -1;
  53     }
  54   else
  55     {
  56       ret = n;
  57     }
  58
  59   _hl_delete ();
  60
  61   return ret;
  62 }
  63
  64 off_t
  65 _lseek (int fd, off_t offset, int whence)
  66 {
  67   return _hl_lseek (fd, offset, whence);
  68 }