Squashed 'third_party/gperftools/' content from commit 54505f1

Change-Id: Id02e833828732b0efe7dac722b8485279e67c5fa
git-subtree-dir: third_party/gperftools
git-subtree-split: 54505f1d50c2d1f4676f5e87090b64a117fd980e
diff --git a/src/symbolize.cc b/src/symbolize.cc
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+++ b/src/symbolize.cc
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+// -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*-
+// Copyright (c) 2009, Google Inc.
+// All rights reserved.
+// 
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+// 
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+// 
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// ---
+// Author: Craig Silverstein
+//
+// This forks out to pprof to do the actual symbolizing.  We might
+// be better off writing our own in C++.
+
+#include "config.h"
+#include "symbolize.h"
+#include <stdlib.h>
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>   // for write()
+#endif
+#ifdef HAVE_SYS_SOCKET_H
+#include <sys/socket.h>   // for socketpair() -- needed by Symbolize
+#endif
+#ifdef HAVE_SYS_WAIT_H
+#include <sys/wait.h>   // for wait() -- needed by Symbolize
+#endif
+#ifdef HAVE_POLL_H
+#include <poll.h>
+#endif
+#ifdef __MACH__
+#include <mach-o/dyld.h>   // for GetProgramInvocationName()
+#include <limits.h>        // for PATH_MAX
+#endif
+#if defined(__CYGWIN__) || defined(__CYGWIN32__)
+#include <io.h>            // for get_osfhandle()
+#endif
+#include <string>
+#include "base/commandlineflags.h"
+#include "base/logging.h"
+#include "base/sysinfo.h"
+
+using std::string;
+using tcmalloc::DumpProcSelfMaps;   // from sysinfo.h
+
+
+DEFINE_string(symbolize_pprof,
+              EnvToString("PPROF_PATH", "pprof"),
+              "Path to pprof to call for reporting function names.");
+
+// heap_profile_table_pprof may be referenced after destructors are
+// called (since that's when leak-checking is done), so we make
+// a more-permanent copy that won't ever get destroyed.
+static string* g_pprof_path = new string(FLAGS_symbolize_pprof);
+
+// Returns NULL if we're on an OS where we can't get the invocation name.
+// Using a static var is ok because we're not called from a thread.
+static const char* GetProgramInvocationName() {
+#if defined(HAVE_PROGRAM_INVOCATION_NAME)
+#ifdef __UCLIBC__
+  extern const char* program_invocation_name; // uclibc provides this
+#else
+  extern char* program_invocation_name;  // gcc provides this
+#endif
+  return program_invocation_name;
+#elif defined(__MACH__)
+  // We don't want to allocate memory for this since we may be
+  // calculating it when memory is corrupted.
+  static char program_invocation_name[PATH_MAX];
+  if (program_invocation_name[0] == '\0') {  // first time calculating
+    uint32_t length = sizeof(program_invocation_name);
+    if (_NSGetExecutablePath(program_invocation_name, &length))
+      return NULL;
+  }
+  return program_invocation_name;
+#else
+  return NULL;   // figure out a way to get argv[0]
+#endif
+}
+
+// Prints an error message when you can't run Symbolize().
+static void PrintError(const char* reason) {
+  RAW_LOG(ERROR,
+          "*** WARNING: Cannot convert addresses to symbols in output below.\n"
+          "*** Reason: %s\n"
+          "*** If you cannot fix this, try running pprof directly.\n",
+          reason);
+}
+
+void SymbolTable::Add(const void* addr) {
+  symbolization_table_[addr] = "";
+}
+
+const char* SymbolTable::GetSymbol(const void* addr) {
+  return symbolization_table_[addr];
+}
+
+// Updates symbolization_table with the pointers to symbol names corresponding
+// to its keys. The symbol names are stored in out, which is allocated and
+// freed by the caller of this routine.
+// Note that the forking/etc is not thread-safe or re-entrant.  That's
+// ok for the purpose we need -- reporting leaks detected by heap-checker
+// -- but be careful if you decide to use this routine for other purposes.
+// Returns number of symbols read on error.  If can't symbolize, returns 0
+// and emits an error message about why.
+int SymbolTable::Symbolize() {
+#if !defined(HAVE_UNISTD_H)  || !defined(HAVE_SYS_SOCKET_H) || !defined(HAVE_SYS_WAIT_H)
+  PrintError("Perftools does not know how to call a sub-process on this O/S");
+  return 0;
+#else
+  const char* argv0 = GetProgramInvocationName();
+  if (argv0 == NULL) {  // can't call symbolize if we can't figure out our name
+    PrintError("Cannot figure out the name of this executable (argv0)");
+    return 0;
+  }
+  if (access(g_pprof_path->c_str(), R_OK) != 0) {
+    PrintError("Cannot find 'pprof' (is PPROF_PATH set correctly?)");
+    return 0;
+  }
+
+  // All this work is to do two-way communication.  ugh.
+  int *child_in = NULL;   // file descriptors
+  int *child_out = NULL;  // for now, we don't worry about child_err
+  int child_fds[5][2];    // socketpair may be called up to five times below
+
+  // The client program may close its stdin and/or stdout and/or stderr
+  // thus allowing socketpair to reuse file descriptors 0, 1 or 2.
+  // In this case the communication between the forked processes may be broken
+  // if either the parent or the child tries to close or duplicate these
+  // descriptors. The loop below produces two pairs of file descriptors, each
+  // greater than 2 (stderr).
+  for (int i = 0; i < 5; i++) {
+    if (socketpair(AF_UNIX, SOCK_STREAM, 0, child_fds[i]) == -1) {
+      for (int j = 0; j < i; j++) {
+        close(child_fds[j][0]);
+        close(child_fds[j][1]);
+        PrintError("Cannot create a socket pair");
+      }
+      return 0;
+    } else {
+      if ((child_fds[i][0] > 2) && (child_fds[i][1] > 2)) {
+        if (child_in == NULL) {
+          child_in = child_fds[i];
+        } else {
+          child_out = child_fds[i];
+          for (int j = 0; j < i; j++) {
+            if (child_fds[j] == child_in) continue;
+            close(child_fds[j][0]);
+            close(child_fds[j][1]);
+          }
+          break;
+        }
+      }
+    }
+  }
+
+  switch (fork()) {
+    case -1: {  // error
+      close(child_in[0]);
+      close(child_in[1]);
+      close(child_out[0]);
+      close(child_out[1]);
+      PrintError("Unknown error calling fork()");
+      return 0;
+    }
+    case 0: {  // child
+      close(child_in[1]);   // child uses the 0's, parent uses the 1's
+      close(child_out[1]);  // child uses the 0's, parent uses the 1's
+      close(0);
+      close(1);
+      if (dup2(child_in[0], 0) == -1) _exit(1);
+      if (dup2(child_out[0], 1) == -1) _exit(2);
+      // Unset vars that might cause trouble when we fork
+      unsetenv("CPUPROFILE");
+      unsetenv("HEAPPROFILE");
+      unsetenv("HEAPCHECK");
+      unsetenv("PERFTOOLS_VERBOSE");
+      execlp(g_pprof_path->c_str(), g_pprof_path->c_str(),
+             "--symbols", argv0, NULL);
+      _exit(3);  // if execvp fails, it's bad news for us
+    }
+    default: {  // parent
+      close(child_in[0]);   // child uses the 0's, parent uses the 1's
+      close(child_out[0]);  // child uses the 0's, parent uses the 1's
+#ifdef HAVE_POLL_H
+      // Waiting for 1ms seems to give the OS time to notice any errors.
+      poll(0, 0, 1);
+      // For maximum safety, we check to make sure the execlp
+      // succeeded before trying to write.  (Otherwise we'll get a
+      // SIGPIPE.)  For systems without poll.h, we'll just skip this
+      // check, and trust that the user set PPROF_PATH correctly!
+      struct pollfd pfd = { child_in[1], POLLOUT, 0 };
+      if (!poll(&pfd, 1, 0) || !(pfd.revents & POLLOUT) ||
+          (pfd.revents & (POLLHUP|POLLERR))) {
+        PrintError("Cannot run 'pprof' (is PPROF_PATH set correctly?)");
+        return 0;
+      }
+#endif
+#if defined(__CYGWIN__) || defined(__CYGWIN32__)
+      // On cygwin, DumpProcSelfMaps() takes a HANDLE, not an fd.  Convert.
+      const HANDLE symbols_handle = (HANDLE) get_osfhandle(child_in[1]);
+      DumpProcSelfMaps(symbols_handle);
+#else
+      DumpProcSelfMaps(child_in[1]);  // what pprof expects on stdin
+#endif
+
+      // Allocate 24 bytes = ("0x" + 8 bytes + "\n" + overhead) for each
+      // address to feed to pprof.
+      const int kOutBufSize = 24 * symbolization_table_.size();
+      char *pprof_buffer = new char[kOutBufSize];
+      int written = 0;
+      for (SymbolMap::const_iterator iter = symbolization_table_.begin();
+           iter != symbolization_table_.end(); ++iter) {
+        written += snprintf(pprof_buffer + written, kOutBufSize - written,
+                 // pprof expects format to be 0xXXXXXX
+                 "0x%" PRIxPTR "\n", reinterpret_cast<uintptr_t>(iter->first));
+      }
+      write(child_in[1], pprof_buffer, strlen(pprof_buffer));
+      close(child_in[1]);             // that's all we need to write
+
+      const int kSymbolBufferSize = kSymbolSize * symbolization_table_.size();
+      int total_bytes_read = 0;
+      delete[] symbol_buffer_;
+      symbol_buffer_ = new char[kSymbolBufferSize];
+      memset(symbol_buffer_, '\0', kSymbolBufferSize);
+      while (1) {
+        int bytes_read = read(child_out[1], symbol_buffer_ + total_bytes_read,
+                              kSymbolBufferSize - total_bytes_read);
+        if (bytes_read < 0) {
+          close(child_out[1]);
+          PrintError("Cannot read data from pprof");
+          return 0;
+        } else if (bytes_read == 0) {
+          close(child_out[1]);
+          wait(NULL);
+          break;
+        } else {
+          total_bytes_read += bytes_read;
+        }
+      }
+      // We have successfully read the output of pprof into out.  Make sure
+      // the last symbol is full (we can tell because it ends with a \n).
+      if (total_bytes_read == 0 || symbol_buffer_[total_bytes_read - 1] != '\n')
+        return 0;
+      // make the symbolization_table_ values point to the output vector
+      SymbolMap::iterator fill = symbolization_table_.begin();
+      int num_symbols = 0;
+      const char *current_name = symbol_buffer_;
+      for (int i = 0; i < total_bytes_read; i++) {
+        if (symbol_buffer_[i] == '\n') {
+          fill->second = current_name;
+          symbol_buffer_[i] = '\0';
+          current_name = symbol_buffer_ + i + 1;
+          fill++;
+          num_symbols++;
+        }
+      }
+      return num_symbols;
+    }
+  }
+  PrintError("Unkown error (should never occur!)");
+  return 0;  // shouldn't be reachable
+#endif
+}