lib/unwarminder/backtrace.c

   1 /***************************************************************************
   2  * ARM Stack Unwinder, Michael.McTernan.2001@cs.bris.ac.uk
   3  *
   4  * This program is PUBLIC DOMAIN.
   5  * This means that there is no copyright and anyone is able to take a copy
   6  * for free and use it as they wish, with or without modifications, and in
   7  * any context, commercially or otherwise. The only limitation is that I
   8  * don't guarantee that the software is fit for any purpose or accept any
   9  * liability for it's use or misuse - this software is without warranty.
  10  ***************************************************************************
  11  * File Description: Unwinder client that reads local memory.
  12  *   This client reads from local memory and is designed to run on target
  13  *   along with the unwinder.  Memory read requests are implemented by
  14  *   casting a point to read the memory directly, although checks for
  15  *   alignment should probably also be made if this is to be used in
  16  *   production code, as otherwise the ARM may return the memory in a
  17  *   rotated/rolled format, or the MMU may generate an alignment exception
  18  *   if present and so configured.
  19  **************************************************************************/
  20
  21 /***************************************************************************
  22  * Includes
  23  ***************************************************************************/
  24
  25 #include "backtrace.h"
  26
  27 /***************************************************************************
  28  * Prototypes
  29  ***************************************************************************/
  30
  31 static Boolean CliReport(void *data, Int32 address);
  32 static Boolean CliReadW(Int32 a, Int32 *v);
  33 static Boolean CliReadH(Int32 a, Int16 *v);
  34 static Boolean CliReadB(Int32 a, Int8  *v);
  35
  36 /***************************************************************************
  37  * Variables
  38  ***************************************************************************/
  39
  40 /* Table of function pointers for passing to the unwinder */
  41 const UnwindCallbacks cliCallbacks =
  42     {
  43         CliReport,
  44         CliReadW,
  45         CliReadH,
  46         CliReadB
  47 #if defined(UNW_DEBUG)
  48        ,printf
  49 #endif
  50     };
  51
  52
  53 /***************************************************************************
  54  * Callbacks
  55  ***************************************************************************/
  56
  57 /***************************************************************************
  58  *
  59  * Function:     CliReport
  60  *
  61  * Parameters:   data    - Pointer to data passed to UnwindStart()
  62  *               address - The return address of a stack frame.
  63  *
  64  * Returns:      TRUE if unwinding should continue, otherwise FALSE to
  65  *                 indicate that unwinding should stop.
  66  *
  67  * Description:  This function is called from the unwinder each time a stack
  68  *                 frame has been unwound.  The LSB of address indicates if
  69  *                 the processor is in ARM mode (LSB clear) or Thumb (LSB
  70  *                 set).
  71  *
  72  ***************************************************************************/
  73 static Boolean CliReport(void *data, Int32 address)
  74 {
  75     /* CliStack *s = (CliStack *)data; */
  76     unsigned *line = (unsigned *)data;
  77
  78
  79     lcd_putsf(0, (*line)++, "    %c: 0x%08x",
  80               (address & 0x1) ? 'T' : 'A',
  81               address & (~0x1));
  82     lcd_update();
  83
  84     return TRUE;
  85 }
  86
  87 static Boolean CliReadW(const Int32 a, Int32 *v)
  88 {
  89     *v = *(Int32 *)a;
  90     return TRUE;
  91 }
  92
  93 static Boolean CliReadH(const Int32 a, Int16 *v)
  94 {
  95     *v = *(Int16 *)a;
  96     return TRUE;
  97 }
  98
  99 static Boolean CliReadB(const Int32 a, Int8 *v)
 100 {
 101     *v = *(Int8 *)a;
 102     return TRUE;
 103 }
 104
 105 Boolean CliInvalidateW(const Int32 a)
 106 {
 107     *(Int32 *)a = 0xdeadbeef;
 108     return TRUE;
 109 }
 110
 111 void backtrace(int pcAddr, int spAddr, unsigned *line)
 112 {
 113     UnwResult r;
 114
 115     lcd_putsf(0, (*line)++, "bt pc: 0x%08x, sp: 0x%08x", pcAddr, spAddr);
 116     lcd_update();
 117
 118     r = UnwindStart(pcAddr, spAddr, &cliCallbacks, (void *)line);
 119
 120     lcd_puts(0, (*line)++, "bt end");
 121     lcd_update();
 122 }
 123
 124 /* END OF FILE */