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--- /dev/null
+++ xnu/xnu-1228/libkern/gen/OSDebug.cpp
@@ -0,0 +1,253 @@
+/*
+ * Copyright (c) 2005 Apple Computer, Inc. All rights reserved.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ */
+
+// NOTE: This file is only c++ so I can get static initialisers going
+#include <libkern/OSDebug.h>
+
+#include <sys/cdefs.h>
+
+#include <stdarg.h>
+#include <mach/mach_types.h>
+#include <mach/kmod.h>
+#include <kern/lock.h>
+
+#include <libkern/libkern.h> // From bsd's libkern directory
+#include <mach/vm_param.h>
+
+#include <sys/kdebug.h>
+extern int etext;
+__BEGIN_DECLS
+// From osmfk/kern/thread.h but considered to be private
+extern vm_offset_t min_valid_stack_address(void);
+extern vm_offset_t max_valid_stack_address(void);
+
+// From osfmk/kmod.c
+extern void kmod_dump_log(vm_offset_t *addr, unsigned int cnt);
+
+extern addr64_t kvtophys(vm_offset_t va);
+#if __arm__
+extern int copyinframe(vm_address_t fp, uint32_t *frame);
+#endif
+
+__END_DECLS
+
+static mutex_t *sOSReportLock = mutex_alloc(0);
+
+/* Use kernel_debug() to log a backtrace */
+void
+trace_backtrace(unsigned int debugid, unsigned int debugid2, int size, int data) {
+ void *bt[16];
+ const unsigned cnt = sizeof(bt) / sizeof(bt[0]);
+ unsigned i;
+ int found = 0;
+
+ OSBacktrace(bt, cnt);
+
+ /* find first non-kernel frame */
+ for (i = 3; i < cnt && bt[i]; i++) {
+ if (bt[i] > (void*)&etext) {
+ found = 1;
+ break;
+ }
+ }
+ /*
+ * if there are non-kernel frames, only log these
+ * otherwise, log everything but the first two
+ */
+ if (!found) i=2;
+
+#define safe_bt(a) (int)(a<cnt ? bt[a] : 0)
+ kernel_debug(debugid, data, size, safe_bt(i), safe_bt(i+1), 0);
+ kernel_debug(debugid2, safe_bt(i+2), safe_bt(i+3), safe_bt(i+4), safe_bt(i+5), 0);
+}
+
+/* Report a message with a 4 entry backtrace - very slow */
+void
+OSReportWithBacktrace(const char *str, ...)
+{
+ char buf[128];
+ void *bt[9];
+ const unsigned cnt = sizeof(bt) / sizeof(bt[0]);
+ va_list listp;
+
+ // Ignore the our and our callers stackframes, skipping frames 0 & 1
+ (void) OSBacktrace(bt, cnt);
+
+ va_start(listp, str);
+ vsnprintf(buf, sizeof(buf), str, listp);
+ va_end(listp);
+
+ mutex_lock(sOSReportLock);
+ {
+ printf("%s\nBacktrace %p %p %p %p %p %p %p\n",
+ buf, bt[2], bt[3], bt[4], bt[5], bt[6], bt[7], bt[8]);
+ kmod_dump_log((vm_offset_t *) &bt[2], cnt - 2);
+ }
+ mutex_unlock(sOSReportLock);
+}
+
+static vm_offset_t minstackaddr = min_valid_stack_address();
+static vm_offset_t maxstackaddr = max_valid_stack_address();
+
+#if __i386__
+#define i386_RETURN_OFFSET 4
+
+static unsigned int
+i386_validate_stackptr(vm_offset_t stackptr)
+{
+ /* Existence and alignment check
+ */
+ if (!stackptr || (stackptr & 0x3))
+ return 0;
+
+ /* Is a virtual->physical translation present?
+ */
+ if (!kvtophys(stackptr))
+ return 0;
+
+ /* Check if the return address lies on the same page;
+ * If not, verify that a translation exists.
+ */
+ if (((PAGE_SIZE - (stackptr & PAGE_MASK)) < i386_RETURN_OFFSET) &&
+ !kvtophys(stackptr + i386_RETURN_OFFSET))
+ return 0;
+ return 1;
+}
+
+static unsigned int
+i386_validate_raddr(vm_offset_t raddr)
+{
+ return ((raddr > VM_MIN_KERNEL_ADDRESS) &&
+ (raddr < VM_MAX_KERNEL_ADDRESS));
+}
+#endif
+
+unsigned OSBacktrace(void **bt, unsigned maxAddrs)
+{
+ unsigned frame;
+
+#if __ppc__
+ vm_offset_t stackptr, stackptr_prev;
+ const vm_offset_t * const mem = (vm_offset_t *) 0;
+ unsigned i = 0;
+
+ __asm__ volatile("mflr %0" : "=r" (stackptr));
+ bt[i++] = (void *) stackptr;
+
+ __asm__ volatile("mr %0,r1" : "=r" (stackptr));
+ for ( ; i < maxAddrs; i++) {
+ // Validate we have a reasonable stackptr
+ if ( !(minstackaddr <= stackptr && stackptr < maxstackaddr)
+ || (stackptr & 3))
+ break;
+
+ stackptr_prev = stackptr;
+ stackptr = mem[stackptr_prev >> 2];
+ if ((stackptr_prev ^ stackptr) > 8 * 1024) // Sanity check
+ break;
+
+ vm_offset_t addr = mem[(stackptr >> 2) + 2];
+ if ((addr & 3) || (addr < 0x8000)) // More sanity checks
+ break;
+ bt[i] = (void *) addr;
+ }
+ frame = i;
+
+ for ( ; i < maxAddrs; i++)
+ bt[i] = (void *) 0;
+#elif __i386__
+#define SANE_i386_FRAME_SIZE 8*1024
+ vm_offset_t stackptr, stackptr_prev, raddr;
+ unsigned frame_index = 0;
+/* Obtain current frame pointer */
+ __asm__ volatile("movl %%ebp, %0" : "=m" (stackptr));
+
+ if (!i386_validate_stackptr(stackptr))
+ goto pad;
+
+ raddr = *((vm_offset_t *) (stackptr + i386_RETURN_OFFSET));
+
+ if (!i386_validate_raddr(raddr))
+ goto pad;
+
+ bt[frame_index++] = (void *) raddr;
+
+ for ( ; frame_index < maxAddrs; frame_index++) {
+ stackptr_prev = stackptr;
+ stackptr = *((vm_offset_t *) stackptr_prev);
+
+ if (!i386_validate_stackptr(stackptr))
+ break;
+ /* Stack grows downwards */
+ if (stackptr < stackptr_prev)
+ break;
+
+ if ((stackptr_prev ^ stackptr) > SANE_i386_FRAME_SIZE)
+ break;
+
+ raddr = *((vm_offset_t *) (stackptr + i386_RETURN_OFFSET));
+
+ if (!i386_validate_raddr(raddr))
+ break;
+
+ bt[frame_index] = (void *) raddr;
+ }
+pad:
+ frame = frame_index;
+
+ for ( ; frame_index < maxAddrs; frame_index++)
+ bt[frame_index] = (void *) 0;
+#elif __arm__
+ uint32_t i= 0;
+ uint32_t frameb[2];
+ uint32_t fp= 0;
+
+ // get the current frame pointer for this thread
+ __asm__ volatile("mov %0,r7" : "=r" (fp));
+
+ // now crawl up the stack recording the link value of each frame
+ do {
+ // check bounds
+ if ((fp == 0) || ((fp & 3) != 0) || (fp > VM_MAX_KERNEL_ADDRESS) || (fp < VM_MIN_KERNEL_ADDRESS)) {
+ break;
+ }
+ // safely read frame
+ if (copyinframe(fp, frameb) != 0) {
+ break;
+ }
+
+ // No need to use copyin as this is always a kernel address, see check above
+ bt[i] = (void*)frameb[1]; // link register
+ fp = frameb[0];
+ } while (++i < maxAddrs);
+ frame= i;
+#else
+#error arch
+#endif
+ return frame;
+}