Initial Contribution
diff --git a/libs/utils/CallStack.cpp b/libs/utils/CallStack.cpp
new file mode 100644
index 0000000..4968666
--- /dev/null
+++ b/libs/utils/CallStack.cpp
@@ -0,0 +1,335 @@
+/*
+ * Copyright (C) 2007 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#define LOG_TAG "CallStack"
+
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#if HAVE_DLADDR
+#include <dlfcn.h>
+#endif
+
+#if HAVE_CXXABI
+#include <cxxabi.h>
+#endif
+
+#include <unwind.h>
+
+#include <utils/Log.h>
+#include <utils/Errors.h>
+#include <utils/CallStack.h>
+#include <utils/threads.h>
+
+
+/*****************************************************************************/
+namespace android {
+
+
+typedef struct {
+ size_t count;
+ size_t ignore;
+ const void** addrs;
+} stack_crawl_state_t;
+
+static
+_Unwind_Reason_Code trace_function(_Unwind_Context *context, void *arg)
+{
+ stack_crawl_state_t* state = (stack_crawl_state_t*)arg;
+ if (state->count) {
+ void* ip = (void*)_Unwind_GetIP(context);
+ if (ip) {
+ if (state->ignore) {
+ state->ignore--;
+ } else {
+ state->addrs[0] = ip;
+ state->addrs++;
+ state->count--;
+ }
+ }
+ }
+ return _URC_NO_REASON;
+}
+
+static
+int backtrace(const void** addrs, size_t ignore, size_t size)
+{
+ stack_crawl_state_t state;
+ state.count = size;
+ state.ignore = ignore;
+ state.addrs = addrs;
+ _Unwind_Backtrace(trace_function, (void*)&state);
+ return size - state.count;
+}
+
+/*****************************************************************************/
+
+static
+const char *lookup_symbol(const void* addr, uint32_t *offset, char* name, size_t bufSize)
+{
+#if HAVE_DLADDR
+ Dl_info info;
+ if (dladdr(addr, &info)) {
+ *offset = (uint32_t)info.dli_saddr;
+ return info.dli_sname;
+ }
+#endif
+ return NULL;
+}
+
+static
+int32_t linux_gcc_demangler(const char *mangled_name, char *unmangled_name, size_t buffersize)
+{
+ size_t out_len = 0;
+#if HAVE_CXXABI
+ int status = 0;
+ char *demangled = abi::__cxa_demangle(mangled_name, 0, &out_len, &status);
+ if (status == 0) {
+ // OK
+ if (out_len < buffersize) memcpy(unmangled_name, demangled, out_len);
+ else out_len = 0;
+ free(demangled);
+ } else {
+ out_len = 0;
+ }
+#endif
+ return out_len;
+}
+
+/*****************************************************************************/
+
+class MapInfo {
+ struct mapinfo {
+ struct mapinfo *next;
+ unsigned start;
+ unsigned end;
+ char name[];
+ };
+
+ const char *map_to_name(unsigned pc, const char* def) {
+ mapinfo* mi = getMapInfoList();
+ while(mi) {
+ if ((pc >= mi->start) && (pc < mi->end))
+ return mi->name;
+ mi = mi->next;
+ }
+ return def;
+ }
+
+ mapinfo *parse_maps_line(char *line) {
+ mapinfo *mi;
+ int len = strlen(line);
+ if (len < 1) return 0;
+ line[--len] = 0;
+ if (len < 50) return 0;
+ if (line[20] != 'x') return 0;
+ mi = (mapinfo*)malloc(sizeof(mapinfo) + (len - 47));
+ if (mi == 0) return 0;
+ mi->start = strtoul(line, 0, 16);
+ mi->end = strtoul(line + 9, 0, 16);
+ mi->next = 0;
+ strcpy(mi->name, line + 49);
+ return mi;
+ }
+
+ mapinfo* getMapInfoList() {
+ Mutex::Autolock _l(mLock);
+ if (milist == 0) {
+ char data[1024];
+ FILE *fp;
+ sprintf(data, "/proc/%d/maps", getpid());
+ fp = fopen(data, "r");
+ if (fp) {
+ while(fgets(data, 1024, fp)) {
+ mapinfo *mi = parse_maps_line(data);
+ if(mi) {
+ mi->next = milist;
+ milist = mi;
+ }
+ }
+ fclose(fp);
+ }
+ }
+ return milist;
+ }
+ mapinfo* milist;
+ Mutex mLock;
+ static MapInfo sMapInfo;
+
+public:
+ MapInfo()
+ : milist(0) {
+ }
+
+ ~MapInfo() {
+ while (milist) {
+ mapinfo *next = milist->next;
+ free(milist);
+ milist = next;
+ }
+ }
+
+ static const char *mapAddressToName(const void* pc, const char* def) {
+ return sMapInfo.map_to_name((unsigned)pc, def);
+ }
+
+};
+
+/*****************************************************************************/
+
+MapInfo MapInfo::sMapInfo;
+
+/*****************************************************************************/
+
+CallStack::CallStack()
+ : mCount(0)
+{
+}
+
+CallStack::CallStack(const CallStack& rhs)
+ : mCount(rhs.mCount)
+{
+ if (mCount) {
+ memcpy(mStack, rhs.mStack, mCount*sizeof(void*));
+ }
+}
+
+CallStack::~CallStack()
+{
+}
+
+CallStack& CallStack::operator = (const CallStack& rhs)
+{
+ mCount = rhs.mCount;
+ if (mCount) {
+ memcpy(mStack, rhs.mStack, mCount*sizeof(void*));
+ }
+ return *this;
+}
+
+bool CallStack::operator == (const CallStack& rhs) const {
+ if (mCount != rhs.mCount)
+ return false;
+ return !mCount || (memcmp(mStack, rhs.mStack, mCount*sizeof(void*)) == 0);
+}
+
+bool CallStack::operator != (const CallStack& rhs) const {
+ return !operator == (rhs);
+}
+
+bool CallStack::operator < (const CallStack& rhs) const {
+ if (mCount != rhs.mCount)
+ return mCount < rhs.mCount;
+ return memcmp(mStack, rhs.mStack, mCount*sizeof(void*)) < 0;
+}
+
+bool CallStack::operator >= (const CallStack& rhs) const {
+ return !operator < (rhs);
+}
+
+bool CallStack::operator > (const CallStack& rhs) const {
+ if (mCount != rhs.mCount)
+ return mCount > rhs.mCount;
+ return memcmp(mStack, rhs.mStack, mCount*sizeof(void*)) > 0;
+}
+
+bool CallStack::operator <= (const CallStack& rhs) const {
+ return !operator > (rhs);
+}
+
+const void* CallStack::operator [] (int index) const {
+ if (index >= int(mCount))
+ return 0;
+ return mStack[index];
+}
+
+
+void CallStack::clear()
+{
+ mCount = 0;
+}
+
+void CallStack::update(int32_t ignoreDepth, int32_t maxDepth)
+{
+ if (maxDepth > MAX_DEPTH)
+ maxDepth = MAX_DEPTH;
+ mCount = backtrace(mStack, ignoreDepth, maxDepth);
+}
+
+// Return the stack frame name on the designated level
+String8 CallStack::toStringSingleLevel(const char* prefix, int32_t level) const
+{
+ String8 res;
+ char namebuf[1024];
+ char tmp[256];
+ char tmp1[32];
+ char tmp2[32];
+ uint32_t offs;
+
+ const void* ip = mStack[level];
+ if (!ip) return res;
+
+ if (prefix) res.append(prefix);
+ snprintf(tmp1, 32, "#%02d ", level);
+ res.append(tmp1);
+
+ const char* name = lookup_symbol(ip, &offs, namebuf, sizeof(namebuf));
+ if (name) {
+ if (linux_gcc_demangler(name, tmp, 256) != 0)
+ name = tmp;
+ snprintf(tmp1, 32, "0x%08x: <", (size_t)ip);
+ snprintf(tmp2, 32, ">+0x%08x", offs);
+ res.append(tmp1);
+ res.append(name);
+ res.append(tmp2);
+ } else {
+ name = MapInfo::mapAddressToName(ip, "<unknown>");
+ snprintf(tmp, 256, "pc %08x %s", (size_t)ip, name);
+ res.append(tmp);
+ }
+ res.append("\n");
+
+ return res;
+}
+
+// Dump a stack trace to the log
+void CallStack::dump(const char* prefix) const
+{
+ /*
+ * Sending a single long log may be truncated since the stack levels can
+ * get very deep. So we request function names of each frame individually.
+ */
+ for (int i=0; i<int(mCount); i++) {
+ LOGD("%s", toStringSingleLevel(prefix, i).string());
+ }
+}
+
+// Return a string (possibly very long) containing the complete stack trace
+String8 CallStack::toString(const char* prefix) const
+{
+ String8 res;
+
+ for (int i=0; i<int(mCount); i++) {
+ res.append(toStringSingleLevel(prefix, i).string());
+ }
+
+ return res;
+}
+
+/*****************************************************************************/
+
+}; // namespace android