sim/common/sim-syscall.c

   1 /* Simulator system call support.
   2
   3    Copyright 2002-2021 Free Software Foundation, Inc.
   4
   5    This file is part of simulators.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 /* This must come before any other includes.  */
  21 #include "defs.h"
  22
  23 #include <errno.h>
  24
  25 #include "sim-main.h"
  26 #include "sim-syscall.h"
  27 #include "sim/callback.h"
  28 \f
  29 /* Read/write functions for system call interface.  */
  30
  31 int
  32 sim_syscall_read_mem (host_callback *cb ATTRIBUTE_UNUSED, struct cb_syscall *sc,
  33                       unsigned long taddr, char *buf, int bytes)
  34 {
  35   SIM_DESC sd = (SIM_DESC) sc->p1;
  36   SIM_CPU *cpu = (SIM_CPU *) sc->p2;
  37
  38   TRACE_MEMORY (cpu, "READ (syscall) %i bytes @ 0x%08lx", bytes, taddr);
  39
  40   return sim_core_read_buffer (sd, cpu, read_map, buf, taddr, bytes);
  41 }
  42
  43 int
  44 sim_syscall_write_mem (host_callback *cb ATTRIBUTE_UNUSED, struct cb_syscall *sc,
  45                        unsigned long taddr, const char *buf, int bytes)
  46 {
  47   SIM_DESC sd = (SIM_DESC) sc->p1;
  48   SIM_CPU *cpu = (SIM_CPU *) sc->p2;
  49
  50   TRACE_MEMORY (cpu, "WRITE (syscall) %i bytes @ 0x%08lx", bytes, taddr);
  51
  52   return sim_core_write_buffer (sd, cpu, write_map, buf, taddr, bytes);
  53 }
  54 \f
  55 /* Main syscall callback for simulators.  */
  56
  57 void
  58 sim_syscall_multi (SIM_CPU *cpu, int func, long arg1, long arg2, long arg3,
  59                    long arg4, long *result, long *result2, int *errcode)
  60 {
  61   SIM_DESC sd = CPU_STATE (cpu);
  62   host_callback *cb = STATE_CALLBACK (sd);
  63   CB_SYSCALL sc;
  64   const char unknown_syscall[] = "<UNKNOWN SYSCALL>";
  65   const char *syscall;
  66
  67   CB_SYSCALL_INIT (&sc);
  68
  69   sc.func = func;
  70   sc.arg1 = arg1;
  71   sc.arg2 = arg2;
  72   sc.arg3 = arg3;
  73   sc.arg4 = arg4;
  74
  75   sc.p1 = sd;
  76   sc.p2 = cpu;
  77   sc.read_mem = sim_syscall_read_mem;
  78   sc.write_mem = sim_syscall_write_mem;
  79
  80   if (cb_syscall (cb, &sc) != CB_RC_OK)
  81     {
  82       /* The cb_syscall func never returns an error, so this is more of a
  83          sanity check.  */
  84       sim_engine_abort (sd, cpu, sim_pc_get (cpu), "cb_syscall failed");
  85     }
  86
  87   syscall = cb_target_str_syscall (cb, func);
  88   if (!syscall)
  89     syscall = unknown_syscall;
  90
  91   if (sc.result == -1)
  92     TRACE_SYSCALL (cpu, "%s[%i](%#lx, %#lx, %#lx) = %li (error = %s[%i])",
  93                    syscall, func, arg1, arg2, arg3, sc.result,
  94                    cb_target_str_errno (cb, sc.errcode), sc.errcode);
  95   else
  96     TRACE_SYSCALL (cpu, "%s[%i](%#lx, %#lx, %#lx) = %li",
  97                    syscall, func, arg1, arg2, arg3, sc.result);
  98
  99   /* Handle syscalls that affect engine behavior.  */
 100   switch (cb_target_to_host_syscall (cb, func))
 101     {
 102     case CB_SYS_exit:
 103       sim_engine_halt (sd, cpu, NULL, sim_pc_get (cpu), sim_exited, arg1);
 104       break;
 105
 106     case CB_SYS_kill:
 107       /* TODO: Need to translate target signal to sim signal, but the sim
 108          doesn't yet have such a mapping layer.  */
 109       if (arg1 == (*cb->getpid) (cb))
 110         sim_engine_halt (sd, cpu, NULL, sim_pc_get (cpu), sim_signalled, arg2);
 111       break;
 112     }
 113
 114   *result = sc.result;
 115   *result2 = sc.result2;
 116   *errcode = sc.errcode;
 117 }
 118
 119 long
 120 sim_syscall (SIM_CPU *cpu, int func, long arg1, long arg2, long arg3, long arg4)
 121 {
 122   long result, result2;
 123   int errcode;
 124
 125   sim_syscall_multi (cpu, func, arg1, arg2, arg3, arg4, &result, &result2,
 126                      &errcode);
 127   if (result == -1)
 128     return -errcode;
 129   else
 130     return result;
 131 }