toolchain/gcc/libgloss/xstormy16/eva_app.c

   1 /* eva_app.c -- Glue code for linking apps to run under GDB debugger control.
   2  *
   3  * Copyright (c) 2001 Red Hat, Inc.
   4  *
   5  * The authors hereby grant permission to use, copy, modify, distribute,
   6  * and license this software and its documentation for any purpose, provided
   7  * that existing copyright notices are retained in all copies and that this
   8  * notice is included verbatim in any distributions. No written agreement,
   9  * license, or royalty fee is required for any of the authorized uses.
  10  * Modifications to this software may be copyrighted by their authors
  11  * and need not follow the licensing terms described here, provided that
  12  * the new terms are clearly indicated on the first page of each file where
  13  * they apply.
  14  */
  15 #include "glue.h"
  16
  17 typedef void (*write_proc_t)(char *buf, int nbytes);
  18 typedef int  (*read_proc_t)(char *buf, int nbytes);
  19
  20 /* There is no "syscall", so we just call directly into the stub code
  21    at fixed addresses. */
  22 #define STUB_WRITE(p,n) ((write_proc_t)0x8084)((p),(n))
  23 #define STUB_READ(p,n)  ((read_proc_t)0x8088)((p),(n))
  24
  25 /*
  26  * print -- do a raw print of a string
  27  */
  28 void
  29 print(char *ptr)
  30 {
  31   STUB_WRITE(ptr, strlen(ptr));
  32 }
  33
  34 /*
  35  * write -- write bytes to the serial port. Ignore fd, since
  36  *          stdout and stderr are the same. Since we have no filesystem,
  37  *          open will only return an error.
  38  */
  39 int
  40 _write (int fd, char *buf, int nbytes)
  41 {
  42   STUB_WRITE(buf, nbytes);
  43   return (nbytes);
  44 }
  45
  46 int
  47 _read (int fd, char *buf, int nbytes)
  48 {
  49   return STUB_READ(buf, nbytes);
  50 }
  51
  52 extern char _end[];
  53 #define HEAP_LIMIT ((char *)0xffff)
  54
  55 void *
  56 _sbrk(int inc)
  57 {
  58   static char *heap_ptr = _end;
  59   void *base;
  60
  61   if (inc > (HEAP_LIMIT - heap_ptr))
  62     return (void *)-1;
  63
  64   base = heap_ptr;
  65   heap_ptr += inc;
  66
  67   return base;
  68 }
  69
  70 void
  71 _exit(int n)
  72 {
  73   while (1)
  74    {
  75      asm volatile ("nop");
  76      asm volatile (".hword 0x0006");  /* breakpoint (special illegal insn) */
  77    }
  78 }