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authorGravatar Abseil Team <absl-team@google.com>2018-04-18 05:56:39 -0700
committerGravatar Jon Cohen <cohenjon@google.com>2018-04-19 10:19:32 -0400
commit5b535401665cc6aa96d54a5c9b0901153d97210f (patch)
tree8d45863656540c8ec81eb7d2742c9191c33ca935 /absl/debugging/internal
parenta7e522daf1ec9cda69b356472f662142dd0c1215 (diff)
- ed0ba496fe01eb8edfa86beade8a37768e7c12ef Updates the API for Exception Safety testing to use build... by Abseil Team <absl-team@google.com>
- c4b7a4e517c9404932c45f2f9f92eb7dc694e45d Internal change by Abseil Team <absl-team@google.com> - 76c78ed9385f65d881511645446e0bb8ababf6ec Add missing ABSL_PREDICT_FALSE to one of FixedArray::at()... by Abseil Team <absl-team@google.com> - 1204fb1c46f007dd9dfb7d9abf3e96c58835d193 Internal change. by Greg Falcon <gfalcon@google.com> - f1f47c98a026bc5e425ae83ff4a2eb391bbd3d9b Add internal-only functionality to examine the stack, to ... by Derek Mauro <dmauro@google.com> - 30d63097cd268d912f917526f6511005580465c4 fix typo by Abseil Team <absl-team@google.com> - 942d7efa6cf54cd248ca57dcaf3c245188b52a76 Remove unnecessary semicolons from comment examples. by Abseil Team <absl-team@google.com> - 7db0669cf23a06d934d3ed8c76aee4e4e23b7e04 Remove malloc_hook and malloc_extension from our internal... by Greg Falcon <gfalcon@google.com> - 0190f1063d101b1ded355019df2e1d325931f6c7 Make the maximum length of a string view equal difference... by Abseil Team <absl-team@google.com> - c8ae37cbce29449b02115a0ebd435ddc3d7ab062 Add namespace qualification. by Shaindel Schwartz <shaindel@google.com> - ff70afe2e6e3dd39f51ce9829e3e1f18231bf4d7 Fix internal/direct_mmap.h for non-linux builds. by Greg Falcon <gfalcon@google.com> GitOrigin-RevId: ed0ba496fe01eb8edfa86beade8a37768e7c12ef Change-Id: I7595ee3480d1d6724fd3797c15ba9d9be0d17e62
Diffstat (limited to 'absl/debugging/internal')
-rw-r--r--absl/debugging/internal/examine_stack.cc147
-rw-r--r--absl/debugging/internal/examine_stack.h38
2 files changed, 185 insertions, 0 deletions
diff --git a/absl/debugging/internal/examine_stack.cc b/absl/debugging/internal/examine_stack.cc
new file mode 100644
index 00000000..261daae9
--- /dev/null
+++ b/absl/debugging/internal/examine_stack.cc
@@ -0,0 +1,147 @@
+//
+// Copyright 2018 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "absl/debugging/internal/examine_stack.h"
+
+#ifndef _WIN32
+#include <unistd.h>
+#endif
+
+#include <csignal>
+#include <cstdio>
+
+#include "absl/base/attributes.h"
+#include "absl/base/internal/raw_logging.h"
+#include "absl/base/macros.h"
+#include "absl/debugging/stacktrace.h"
+#include "absl/debugging/symbolize.h"
+
+namespace absl {
+namespace debugging_internal {
+
+// Returns the program counter from signal context, nullptr if
+// unknown. vuc is a ucontext_t*. We use void* to avoid the use of
+// ucontext_t on non-POSIX systems.
+void* GetProgramCounter(void* vuc) {
+#ifdef __linux__
+ if (vuc != nullptr) {
+ ucontext_t* context = reinterpret_cast<ucontext_t*>(vuc);
+#if defined(__aarch64__)
+ return reinterpret_cast<void*>(context->uc_mcontext.pc);
+#elif defined(__arm__)
+ return reinterpret_cast<void*>(context->uc_mcontext.arm_pc);
+#elif defined(__i386__)
+ if (14 < ABSL_ARRAYSIZE(context->uc_mcontext.gregs))
+ return reinterpret_cast<void*>(context->uc_mcontext.gregs[14]);
+#elif defined(__powerpc64__)
+ return reinterpret_cast<void*>(context->uc_mcontext.gp_regs[32]);
+#elif defined(__powerpc__)
+ return reinterpret_cast<void*>(context->uc_mcontext.regs->nip);
+#elif defined(__x86_64__)
+ if (16 < ABSL_ARRAYSIZE(context->uc_mcontext.gregs))
+ return reinterpret_cast<void*>(context->uc_mcontext.gregs[16]);
+#else
+#error "Undefined Architecture."
+#endif
+ }
+#elif defined(__akaros__)
+ auto* ctx = reinterpret_cast<struct user_context*>(vuc);
+ return reinterpret_cast<void*>(get_user_ctx_pc(ctx));
+#endif
+ static_cast<void>(vuc);
+ return nullptr;
+}
+
+// The %p field width for printf() functions is two characters per byte,
+// and two extra for the leading "0x".
+static constexpr int kPrintfPointerFieldWidth = 2 + 2 * sizeof(void*);
+
+// Print a program counter, its stack frame size, and its symbol name.
+// Note that there is a separate symbolize_pc argument. Return addresses may be
+// at the end of the function, and this allows the caller to back up from pc if
+// appropriate.
+static void DumpPCAndFrameSizeAndSymbol(void (*writerfn)(const char*, void*),
+ void* writerfn_arg, void* pc,
+ void* symbolize_pc, int framesize,
+ const char* const prefix) {
+ char tmp[1024];
+ const char* symbol = "(unknown)";
+ if (absl::Symbolize(symbolize_pc, tmp, sizeof(tmp))) {
+ symbol = tmp;
+ }
+ char buf[1024];
+ if (framesize <= 0) {
+ snprintf(buf, sizeof(buf), "%s@ %*p (unknown) %s\n", prefix,
+ kPrintfPointerFieldWidth, pc, symbol);
+ } else {
+ snprintf(buf, sizeof(buf), "%s@ %*p %9d %s\n", prefix,
+ kPrintfPointerFieldWidth, pc, framesize, symbol);
+ }
+ writerfn(buf, writerfn_arg);
+}
+
+// Print a program counter and the corresponding stack frame size.
+static void DumpPCAndFrameSize(void (*writerfn)(const char*, void*),
+ void* writerfn_arg, void* pc, int framesize,
+ const char* const prefix) {
+ char buf[100];
+ if (framesize <= 0) {
+ snprintf(buf, sizeof(buf), "%s@ %*p (unknown)\n", prefix,
+ kPrintfPointerFieldWidth, pc);
+ } else {
+ snprintf(buf, sizeof(buf), "%s@ %*p %9d\n", prefix,
+ kPrintfPointerFieldWidth, pc, framesize);
+ }
+ writerfn(buf, writerfn_arg);
+}
+
+void DumpPCAndFrameSizesAndStackTrace(
+ void* pc, void* const stack[], int frame_sizes[], int depth,
+ int min_dropped_frames, bool symbolize_stacktrace,
+ void (*writerfn)(const char*, void*), void* writerfn_arg) {
+ if (pc != nullptr) {
+ // We don't know the stack frame size for PC, use 0.
+ if (symbolize_stacktrace) {
+ DumpPCAndFrameSizeAndSymbol(writerfn, writerfn_arg, pc, pc, 0, "PC: ");
+ } else {
+ DumpPCAndFrameSize(writerfn, writerfn_arg, pc, 0, "PC: ");
+ }
+ }
+ for (int i = 0; i < depth; i++) {
+ if (symbolize_stacktrace) {
+ // Pass the previous address of pc as the symbol address because pc is a
+ // return address, and an overrun may occur when the function ends with a
+ // call to a function annotated noreturn (e.g. CHECK). Note that we don't
+ // do this for pc above, as the adjustment is only correct for return
+ // addresses.
+ DumpPCAndFrameSizeAndSymbol(writerfn, writerfn_arg, stack[i],
+ reinterpret_cast<char*>(stack[i]) - 1,
+ frame_sizes[i], " ");
+ } else {
+ DumpPCAndFrameSize(writerfn, writerfn_arg, stack[i], frame_sizes[i],
+ " ");
+ }
+ }
+ if (min_dropped_frames > 0) {
+ char buf[100];
+ snprintf(buf, sizeof(buf), " @ ... and at least %d more frames\n",
+ min_dropped_frames);
+ writerfn(buf, writerfn_arg);
+ }
+}
+
+} // namespace debugging_internal
+} // namespace absl
diff --git a/absl/debugging/internal/examine_stack.h b/absl/debugging/internal/examine_stack.h
new file mode 100644
index 00000000..a16c03b2
--- /dev/null
+++ b/absl/debugging/internal/examine_stack.h
@@ -0,0 +1,38 @@
+//
+// Copyright 2018 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef ABSL_DEBUGGING_INTERNAL_EXAMINE_STACK_H_
+#define ABSL_DEBUGGING_INTERNAL_EXAMINE_STACK_H_
+
+namespace absl {
+namespace debugging_internal {
+
+// Returns the program counter from signal context, or nullptr if
+// unknown. `vuc` is a ucontext_t*. We use void* to avoid the use of
+// ucontext_t on non-POSIX systems.
+void* GetProgramCounter(void* vuc);
+
+// Uses `writerfn` to dump the program counter, stack trace, and stack
+// frame sizes.
+void DumpPCAndFrameSizesAndStackTrace(
+ void* pc, void* const stack[], int frame_sizes[], int depth,
+ int min_dropped_frames, bool symbolize_stacktrace,
+ void (*writerfn)(const char*, void*), void* writerfn_arg);
+
+} // namespace debugging_internal
+} // namespace absl
+
+#endif // ABSL_DEBUGGING_INTERNAL_EXAMINE_STACK_H_