granicus.if.org Git - strace/blob - retval.c

   1 /*
   2  * Copyright (c) 2018 The strace developers.
   3  * All rights reserved.
   4  *
   5  * SPDX-License-Identifier: LGPL-2.1-or-later
   6  */
   7
   8 #include "defs.h"
   9 #include "retval.h"
  10
  11 static kernel_long_t *retval_vec;
  12 static size_t retval_vec_capacity; /* size of the arena */
  13 static size_t retval_vec_size;     /* size of the used arena */
  14
  15 static void
  16 expand_retval_vec(void)
  17 {
  18         const size_t old_capacity = retval_vec_capacity;
  19         retval_vec = xgrowarray(retval_vec, &retval_vec_capacity,
  20                                 sizeof(*retval_vec));
  21         memset(retval_vec + old_capacity, 0,
  22                (retval_vec_capacity - old_capacity)
  23                * sizeof(*retval_vec));
  24 }
  25
  26 uint16_t
  27 retval_new(const kernel_long_t rval)
  28 {
  29         const uint16_t idx = retval_vec_size;
  30
  31         if (idx < retval_vec_size)
  32                 error_func_msg_and_die("retval index overflow");
  33
  34         if (retval_vec_size == retval_vec_capacity)
  35                 expand_retval_vec();
  36
  37         retval_vec[idx] = rval;
  38         ++retval_vec_size;
  39
  40         return idx;
  41 }
  42
  43 kernel_long_t
  44 retval_get(const uint16_t rval_idx)
  45 {
  46         if (rval_idx >= retval_vec_size)
  47                 error_func_msg_and_die("rval_idx >= retval_vec_size");
  48
  49         return retval_vec[rval_idx];
  50 }