bootx.tproj/libclite.subproj/printf.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  *  printf.c - printf
  24  *
  25  *  Copyright (c) 1998-2002 Apple Computer, Inc.
  26  *
  27  *  DRI: Josh de Cesare
  28  */
  29
  30 #include <libclite.h>
  31
  32 int printf(const char *format, ...)
  33 {
  34     va_list ap;
  35     va_start(ap, format);
  36     prf(format, (unsigned int *)ap, putchar, 0);
  37     va_end(ap);
  38     return 0;
  39 }
  40
  41
  42 #if DEBUG
  43 #include <stdint.h>
  44
  45 #define BTLEN 10
  46 // ctx and id optional
  47 void dump_backtrace(char *ctx, int id)
  48 {
  49         void *bt[BTLEN];
  50         int cnt;
  51
  52         if (ctx)
  53                 printf("%s ", ctx);
  54         if (id)
  55                 printf("(%d)", id);
  56         if (ctx || id)
  57                 printf(":\n");
  58
  59         cnt = OSBacktrace_ppc(bt, BTLEN);
  60         while(cnt <= BTLEN && cnt--)
  61                 printf("bt[%d]: %x\n", cnt, bt[cnt]);
  62 }
  63
  64 // ported from xnu/libkern/gen/OSDebug.cpp
  65 // (non-__ppc__ #if branches and min/maxstackaddr checks omitted)
  66 unsigned OSBacktrace_ppc(void **bt, unsigned maxAddrs)
  67 {
  68     unsigned frame;
  69
  70 #if __ppc__
  71     uint32_t stackptr, stackptr_prev;
  72     const uint32_t * const mem = (uint32_t *) 0;
  73     unsigned i = 0;
  74
  75     __asm__ volatile("mflr %0" : "=r" (stackptr));
  76     bt[i++] = (void *) stackptr;
  77
  78     __asm__ volatile("mr %0,r1" : "=r" (stackptr));
  79     for ( ; i < maxAddrs; i++) {
  80     // Validate we have a reasonable stackptr
  81     if ( /* !(minstackaddr <= stackptr && stackptr < maxstackaddr)
  82                         || */ (stackptr & 3))
  83         break;
  84
  85     stackptr_prev = stackptr;
  86     stackptr = mem[stackptr_prev >> 2];
  87     if ((stackptr_prev ^ stackptr) > 8 * 1024)  // Sanity check
  88         break;
  89
  90     uint32_t addr = mem[(stackptr >> 2) + 2];
  91     if ((addr & 3) || (addr < 0x8000))  // More sanity checks
  92         break;
  93     bt[i] = (void *) addr;
  94     }
  95     frame = i;
  96
  97     for ( ; i < maxAddrs; i++)
  98         bt[i] = (void *) 0;
  99 #else
 100 #warning "BootX's OSBacktrace_ppc() not intended for other architectures"
 101 #endif
 102
 103     return frame;
 104 }
 105 #endif  // DEBUG