libgloss/arc/hl/hl_write.c

   1 /*
   2  * hl_write.c -- provide _write().
   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 <unistd.h>
  22
  23 #include "hl_toolchain.h"
  24 #include "hl_api.h"
  25
  26
  27 /* Write one chunk to the host file.  Implements HL_SYSCALL_WRITE.  */
  28 static ssize_t
  29 _hl_write (int fd, const char *buf, size_t nbyte)
  30 {
  31   ssize_t ret;
  32   int32_t n;
  33   uint32_t host_errno;
  34   volatile __uncached char *p;
  35
  36   p = _hl_message (HL_SYSCALL_WRITE, "ipi:ii",
  37                    (uint32_t) fd,               /* i */
  38                    buf, (uint32_t) nbyte,       /* p */
  39                    (uint32_t) nbyte,            /* i */
  40                    (uint32_t *) &n,             /* :i */
  41                    (uint32_t *) &host_errno     /* :i */);
  42
  43   if (p == NULL)
  44     {
  45       errno = ETIMEDOUT;
  46       ret = -1;
  47     }
  48   else if (n < 0)
  49     {
  50       errno = host_errno;
  51       ret = -1;
  52     }
  53   else
  54     {
  55       ret = n;
  56     }
  57
  58   _hl_delete ();
  59
  60   return ret;
  61 }
  62
  63 ssize_t
  64 _write (int fd, const char *buf, size_t nbyte)
  65 {
  66   const uint32_t hl_iochunk = _hl_iochunk_size ();
  67   size_t to_write = nbyte;
  68   size_t offset = 0;
  69   ssize_t ret = 0;
  70
  71   while (to_write > hl_iochunk)
  72     {
  73       ret = _hl_write (fd, buf + offset, hl_iochunk);
  74
  75       if (ret < 0)
  76         return ret;
  77
  78       offset += ret;
  79
  80       if (ret != (ssize_t) hl_iochunk)
  81         return offset;
  82
  83       to_write -= hl_iochunk;
  84     }
  85
  86   if (to_write)
  87     {
  88       ret = _hl_write (fd, buf + offset, to_write);
  89
  90       if (ret < 0)
  91         return ret;
  92
  93       ret += offset;
  94     }
  95
  96   return ret;
  97 }