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Diffstat (limited to 'contrib/bind9/lib/isc/backtrace.c')
| -rw-r--r-- | contrib/bind9/lib/isc/backtrace.c | 285 |
1 files changed, 0 insertions, 285 deletions
diff --git a/contrib/bind9/lib/isc/backtrace.c b/contrib/bind9/lib/isc/backtrace.c deleted file mode 100644 index d2f044c..0000000 --- a/contrib/bind9/lib/isc/backtrace.c +++ /dev/null @@ -1,285 +0,0 @@ -/* - * Copyright (C) 2009 Internet Systems Consortium, Inc. ("ISC") - * - * Permission to use, copy, modify, and/or distribute this software for any - * purpose with or without fee is hereby granted, provided that the above - * copyright notice and this permission notice appear in all copies. - * - * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH - * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY - * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, - * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM - * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE - * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR - * PERFORMANCE OF THIS SOFTWARE. - */ - -/* $Id: backtrace.c,v 1.3 2009/09/02 23:48:02 tbox Exp $ */ - -/*! \file */ - -#include "config.h" - -#include <string.h> -#include <stdlib.h> -#ifdef HAVE_LIBCTRACE -#include <execinfo.h> -#endif - -#include <isc/backtrace.h> -#include <isc/result.h> -#include <isc/util.h> - -#ifdef ISC_PLATFORM_USEBACKTRACE -/* - * Getting a back trace of a running process is tricky and highly platform - * dependent. Our current approach is as follows: - * 1. If the system library supports the "backtrace()" function, use it. - * 2. Otherwise, if the compiler is gcc and the architecture is x86_64 or IA64, - * then use gcc's (hidden) Unwind_Backtrace() function. Note that this - * function doesn't work for C programs on many other architectures. - * 3. Otherwise, if the architecture x86 or x86_64, try to unwind the stack - * frame following frame pointers. This assumes the executable binary - * compiled with frame pointers; this is not always true for x86_64 (rather, - * compiler optimizations often disable frame pointers). The validation - * checks in getnextframeptr() hopefully rejects bogus values stored in - * the RBP register in such a case. If the backtrace function itself crashes - * due to this problem, the whole package should be rebuilt with - * --disable-backtrace. - */ -#ifdef HAVE_LIBCTRACE -#define BACKTRACE_LIBC -#elif defined(__GNUC__) && (defined(__x86_64__) || defined(__ia64__)) -#define BACKTRACE_GCC -#elif defined(__x86_64__) || defined(__i386__) -#define BACKTRACE_X86STACK -#else -#define BACKTRACE_DISABLED -#endif /* HAVE_LIBCTRACE */ -#else /* !ISC_PLATFORM_USEBACKTRACE */ -#define BACKTRACE_DISABLED -#endif /* ISC_PLATFORM_USEBACKTRACE */ - -#ifdef BACKTRACE_LIBC -isc_result_t -isc_backtrace_gettrace(void **addrs, int maxaddrs, int *nframes) { - int n; - - /* - * Validate the arguments: intentionally avoid using REQUIRE(). - * See notes in backtrace.h. - */ - if (addrs == NULL || nframes == NULL) - return (ISC_R_FAILURE); - - /* - * backtrace(3) includes this function itself in the address array, - * which should be eliminated from the returned sequence. - */ - n = backtrace(addrs, maxaddrs); - if (n < 2) - return (ISC_R_NOTFOUND); - n--; - memmove(addrs, &addrs[1], sizeof(void *) * n); - *nframes = n; - return (ISC_R_SUCCESS); -} -#elif defined(BACKTRACE_GCC) -extern int _Unwind_Backtrace(void* fn, void* a); -extern void* _Unwind_GetIP(void* ctx); - -typedef struct { - void **result; - int max_depth; - int skip_count; - int count; -} trace_arg_t; - -static int -btcallback(void *uc, void *opq) { - trace_arg_t *arg = (trace_arg_t *)opq; - - if (arg->skip_count > 0) - arg->skip_count--; - else - arg->result[arg->count++] = (void *)_Unwind_GetIP(uc); - if (arg->count == arg->max_depth) - return (5); /* _URC_END_OF_STACK */ - - return (0); /* _URC_NO_REASON */ -} - -isc_result_t -isc_backtrace_gettrace(void **addrs, int maxaddrs, int *nframes) { - trace_arg_t arg; - - /* Argument validation: see above. */ - if (addrs == NULL || nframes == NULL) - return (ISC_R_FAILURE); - - arg.skip_count = 1; - arg.result = addrs; - arg.max_depth = maxaddrs; - arg.count = 0; - _Unwind_Backtrace(btcallback, &arg); - - *nframes = arg.count; - - return (ISC_R_SUCCESS); -} -#elif defined(BACKTRACE_X86STACK) -#ifdef __x86_64__ -static unsigned long -getrbp() { - __asm("movq %rbp, %rax\n"); -} -#endif - -static void ** -getnextframeptr(void **sp) { - void **newsp = (void **)*sp; - - /* - * Perform sanity check for the new frame pointer, derived from - * google glog. This can actually be bogus depending on compiler. - */ - - /* prohibit the stack frames from growing downwards */ - if (newsp <= sp) - return (NULL); - - /* A heuristics to reject "too large" frame: this actually happened. */ - if ((char *)newsp - (char *)sp > 100000) - return (NULL); - - /* - * Not sure if other checks used in glog are needed at this moment. - * For our purposes we don't have to consider non-contiguous frames, - * for example. - */ - - return (newsp); -} - -isc_result_t -isc_backtrace_gettrace(void **addrs, int maxaddrs, int *nframes) { - int i = 0; - void **sp; - - /* Argument validation: see above. */ - if (addrs == NULL || nframes == NULL) - return (ISC_R_FAILURE); - -#ifdef __x86_64__ - sp = (void **)getrbp(); - if (sp == NULL) - return (ISC_R_NOTFOUND); - /* - * sp is the frame ptr of this function itself due to the call to - * getrbp(), so need to unwind one frame for consistency. - */ - sp = getnextframeptr(sp); -#else - /* - * i386: the frame pointer is stored 2 words below the address for the - * first argument. Note that the body of this function cannot be - * inlined since it depends on the address of the function argument. - */ - sp = (void **)&addrs - 2; -#endif - - while (sp != NULL && i < maxaddrs) { - addrs[i++] = *(sp + 1); - sp = getnextframeptr(sp); - } - - *nframes = i; - - return (ISC_R_SUCCESS); -} -#elif defined(BACKTRACE_DISABLED) -isc_result_t -isc_backtrace_gettrace(void **addrs, int maxaddrs, int *nframes) { - /* Argument validation: see above. */ - if (addrs == NULL || nframes == NULL) - return (ISC_R_FAILURE); - - UNUSED(maxaddrs); - - return (ISC_R_NOTIMPLEMENTED); -} -#endif - -isc_result_t -isc_backtrace_getsymbolfromindex(int index, const void **addrp, - const char **symbolp) -{ - REQUIRE(addrp != NULL && *addrp == NULL); - REQUIRE(symbolp != NULL && *symbolp == NULL); - - if (index < 0 || index >= isc__backtrace_nsymbols) - return (ISC_R_RANGE); - - *addrp = isc__backtrace_symtable[index].addr; - *symbolp = isc__backtrace_symtable[index].symbol; - return (ISC_R_SUCCESS); -} - -static int -symtbl_compare(const void *addr, const void *entryarg) { - const isc_backtrace_symmap_t *entry = entryarg; - const isc_backtrace_symmap_t *end = - &isc__backtrace_symtable[isc__backtrace_nsymbols - 1]; - - if (isc__backtrace_nsymbols == 1 || entry == end) { - if (addr >= entry->addr) { - /* - * If addr is equal to or larger than that of the last - * entry of the table, we cannot be sure if this is - * within a valid range so we consider it valid. - */ - return (0); - } - return (-1); - } - - /* entry + 1 is a valid entry from now on. */ - if (addr < entry->addr) - return (-1); - else if (addr >= (entry + 1)->addr) - return (1); - return (0); -} - -isc_result_t -isc_backtrace_getsymbol(const void *addr, const char **symbolp, - unsigned long *offsetp) -{ - isc_result_t result = ISC_R_SUCCESS; - isc_backtrace_symmap_t *found; - - /* - * Validate the arguments: intentionally avoid using REQUIRE(). - * See notes in backtrace.h. - */ - if (symbolp == NULL || *symbolp != NULL || offsetp == NULL) - return (ISC_R_FAILURE); - - if (isc__backtrace_nsymbols < 1) - return (ISC_R_NOTFOUND); - - /* - * Search the table for the entry that meets: - * entry.addr <= addr < next_entry.addr. - */ - found = bsearch(addr, isc__backtrace_symtable, isc__backtrace_nsymbols, - sizeof(isc__backtrace_symtable[0]), symtbl_compare); - if (found == NULL) - result = ISC_R_NOTFOUND; - else { - *symbolp = found->symbol; - *offsetp = (const char *)addr - (char *)found->addr; - } - - return (result); -} |
