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 #include "safe_read.h"
  27
  28 /***************************************************************************
  29  * Prototypes
  30  ***************************************************************************/
  31
  32 static Boolean CliReport(void *data, Int32 address);
  33 static Boolean CliReadW(Int32 a, Int32 *v);
  34 static Boolean CliReadH(Int32 a, Int16 *v);
  35 static Boolean CliReadB(Int32 a, Int8  *v);
  36
  37 /***************************************************************************
  38  * Variables
  39  ***************************************************************************/
  40
  41 /* Table of function pointers for passing to the unwinder */
  42 const UnwindCallbacks cliCallbacks =
  43     {
  44         CliReport,
  45         CliReadW,
  46         CliReadH,
  47         CliReadB
  48 #if defined(UNW_DEBUG)
  49        ,printf
  50 #endif
  51     };
  52
  53
  54 /***************************************************************************
  55  * Callbacks
  56  ***************************************************************************/
  57
  58 /***************************************************************************
  59  *
  60  * Function:     CliReport
  61  *
  62  * Parameters:   data    - Pointer to data passed to UnwindStart()
  63  *               address - The return address of a stack frame.
  64  *
  65  * Returns:      TRUE if unwinding should continue, otherwise FALSE to
  66  *                 indicate that unwinding should stop.
  67  *
  68  * Description:  This function is called from the unwinder each time a stack
  69  *                 frame has been unwound.  The LSB of address indicates if
  70  *                 the processor is in ARM mode (LSB clear) or Thumb (LSB
  71  *                 set).
  72  *
  73  ***************************************************************************/
  74 static Boolean CliReport(void *data, Int32 address)
  75 {
  76     /* CliStack *s = (CliStack *)data; */
  77     unsigned *line = (unsigned *)data;
  78
  79
  80     lcd_putsf(0, (*line)++, "    %c: %08x",
  81               (address & 0x1) ? 'T' : 'A',
  82               address & (~0x1));
  83     lcd_update();
  84
  85     return TRUE;
  86 }
  87
  88 static Boolean CliReadW(const Int32 a, Int32 *v)
  89 {
  90     return safe_read32((uint32_t *)a, (uint32_t *)v);
  91 }
  92
  93 static Boolean CliReadH(const Int32 a, Int16 *v)
  94 {
  95     return safe_read16((void *)a, (uint16_t *)v);
  96 }
  97
  98 static Boolean CliReadB(const Int32 a, Int8 *v)
  99 {
 100     return safe_read8((void *)a, (uint8_t *)v);
 101 }
 102
 103 Boolean CliInvalidateW(const Int32 a)
 104 {
 105     *(Int32 *)a = 0xdeadbeef;
 106     return TRUE;
 107 }
 108
 109 void backtrace(int pcAddr, int spAddr, unsigned *line)
 110 {
 111     UnwResult r;
 112
 113     lcd_putsf(0, (*line)++, "bt pc: %08x, sp: %08x", pcAddr, spAddr);
 114     lcd_update();
 115
 116     r = UnwindStart(pcAddr, spAddr, &cliCallbacks, (void *)line);
 117
 118     lcd_puts(0, (*line)++, "bt end");
 119     lcd_update();
 120 }
 121
 122 /* END OF FILE */