Initial import.

1 files changed, 304 insertions, 0 deletions

diff --git a/chromium/base/linux_util.cc b/chromium/base/linux_util.cc
new file mode 100644
index 00000000000..5f9ecd43ab1
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+++ b/chromium/base/linux_util.cc
@@ -0,0 +1,304 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/linux_util.h"
+
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <vector>
+
+#include "base/command_line.h"
+#include "base/file_util.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/singleton.h"
+#include "base/path_service.h"
+#include "base/process/launch.h"
+#include "base/strings/string_util.h"
+#include "base/synchronization/lock.h"
+
+namespace {
+
+// Not needed for OS_CHROMEOS.
+#if defined(OS_LINUX)
+enum LinuxDistroState {
+  STATE_DID_NOT_CHECK  = 0,
+  STATE_CHECK_STARTED  = 1,
+  STATE_CHECK_FINISHED = 2,
+};
+
+// Helper class for GetLinuxDistro().
+class LinuxDistroHelper {
+ public:
+  // Retrieves the Singleton.
+  static LinuxDistroHelper* GetInstance() {
+    return Singleton<LinuxDistroHelper>::get();
+  }
+
+  // The simple state machine goes from:
+  // STATE_DID_NOT_CHECK -> STATE_CHECK_STARTED -> STATE_CHECK_FINISHED.
+  LinuxDistroHelper() : state_(STATE_DID_NOT_CHECK) {}
+  ~LinuxDistroHelper() {}
+
+  // Retrieve the current state, if we're in STATE_DID_NOT_CHECK,
+  // we automatically move to STATE_CHECK_STARTED so nobody else will
+  // do the check.
+  LinuxDistroState State() {
+    base::AutoLock scoped_lock(lock_);
+    if (STATE_DID_NOT_CHECK == state_) {
+      state_ = STATE_CHECK_STARTED;
+      return STATE_DID_NOT_CHECK;
+    }
+    return state_;
+  }
+
+  // Indicate the check finished, move to STATE_CHECK_FINISHED.
+  void CheckFinished() {
+    base::AutoLock scoped_lock(lock_);
+    DCHECK_EQ(STATE_CHECK_STARTED, state_);
+    state_ = STATE_CHECK_FINISHED;
+  }
+
+ private:
+  base::Lock lock_;
+  LinuxDistroState state_;
+};
+#endif  // if defined(OS_LINUX)
+
+// expected prefix of the target of the /proc/self/fd/%d link for a socket
+const char kSocketLinkPrefix[] = "socket:[";
+
+// Parse a symlink in /proc/pid/fd/$x and return the inode number of the
+// socket.
+//   inode_out: (output) set to the inode number on success
+//   path: e.g. /proc/1234/fd/5 (must be a UNIX domain socket descriptor)
+//   log: if true, log messages about failure details
+bool ProcPathGetInode(ino_t* inode_out, const char* path, bool log = false) {
+  DCHECK(inode_out);
+  DCHECK(path);
+
+  char buf[256];
+  const ssize_t n = readlink(path, buf, sizeof(buf) - 1);
+  if (n == -1) {
+    if (log) {
+      DLOG(WARNING) << "Failed to read the inode number for a socket from /proc"
+                      "(" << errno << ")";
+    }
+    return false;
+  }
+  buf[n] = 0;
+
+  if (memcmp(kSocketLinkPrefix, buf, sizeof(kSocketLinkPrefix) - 1)) {
+    if (log) {
+      DLOG(WARNING) << "The descriptor passed from the crashing process wasn't "
+                      " a UNIX domain socket.";
+    }
+    return false;
+  }
+
+  char* endptr;
+  const unsigned long long int inode_ul =
+      strtoull(buf + sizeof(kSocketLinkPrefix) - 1, &endptr, 10);
+  if (*endptr != ']')
+    return false;
+
+  if (inode_ul == ULLONG_MAX) {
+    if (log) {
+      DLOG(WARNING) << "Failed to parse a socket's inode number: the number "
+                       "was too large. Please report this bug: " << buf;
+    }
+    return false;
+  }
+
+  *inode_out = inode_ul;
+  return true;
+}
+
+}  // namespace
+
+namespace base {
+
+const char kFindInodeSwitch[] = "--find-inode";
+
+// Account for the terminating null character.
+static const int kDistroSize = 128 + 1;
+
+// We use this static string to hold the Linux distro info. If we
+// crash, the crash handler code will send this in the crash dump.
+char g_linux_distro[kDistroSize] =
+#if defined(OS_CHROMEOS)
+    "CrOS";
+#elif defined(OS_ANDROID)
+    "Android";
+#else  // if defined(OS_LINUX)
+    "Unknown";
+#endif
+
+std::string GetLinuxDistro() {
+#if defined(OS_CHROMEOS) || defined(OS_ANDROID)
+  return g_linux_distro;
+#elif defined(OS_LINUX)
+  LinuxDistroHelper* distro_state_singleton = LinuxDistroHelper::GetInstance();
+  LinuxDistroState state = distro_state_singleton->State();
+  if (STATE_CHECK_FINISHED == state)
+    return g_linux_distro;
+  if (STATE_CHECK_STARTED == state)
+    return "Unknown"; // Don't wait for other thread to finish.
+  DCHECK_EQ(state, STATE_DID_NOT_CHECK);
+  // We do this check only once per process. If it fails, there's
+  // little reason to believe it will work if we attempt to run
+  // lsb_release again.
+  std::vector<std::string> argv;
+  argv.push_back("lsb_release");
+  argv.push_back("-d");
+  std::string output;
+  base::GetAppOutput(CommandLine(argv), &output);
+  if (output.length() > 0) {
+    // lsb_release -d should return: Description:<tab>Distro Info
+    const char field[] = "Description:\t";
+    if (output.compare(0, strlen(field), field) == 0) {
+      SetLinuxDistro(output.substr(strlen(field)));
+    }
+  }
+  distro_state_singleton->CheckFinished();
+  return g_linux_distro;
+#else
+  NOTIMPLEMENTED();
+  return "Unknown";
+#endif
+}
+
+void SetLinuxDistro(const std::string& distro) {
+  std::string trimmed_distro;
+  TrimWhitespaceASCII(distro, TRIM_ALL, &trimmed_distro);
+  base::strlcpy(g_linux_distro, trimmed_distro.c_str(), kDistroSize);
+}
+
+bool FileDescriptorGetInode(ino_t* inode_out, int fd) {
+  DCHECK(inode_out);
+
+  struct stat buf;
+  if (fstat(fd, &buf) < 0)
+    return false;
+
+  if (!S_ISSOCK(buf.st_mode))
+    return false;
+
+  *inode_out = buf.st_ino;
+  return true;
+}
+
+bool FindProcessHoldingSocket(pid_t* pid_out, ino_t socket_inode) {
+  DCHECK(pid_out);
+  bool already_found = false;
+
+  DIR* proc = opendir("/proc");
+  if (!proc) {
+    DLOG(WARNING) << "Cannot open /proc";
+    return false;
+  }
+
+  std::vector<pid_t> pids;
+
+  struct dirent* dent;
+  while ((dent = readdir(proc))) {
+    char* endptr;
+    const unsigned long int pid_ul = strtoul(dent->d_name, &endptr, 10);
+    if (pid_ul == ULONG_MAX || *endptr)
+      continue;
+    pids.push_back(pid_ul);
+  }
+  closedir(proc);
+
+  for (std::vector<pid_t>::const_iterator
+       i = pids.begin(); i != pids.end(); ++i) {
+    const pid_t current_pid = *i;
+    char buf[256];
+    snprintf(buf, sizeof(buf), "/proc/%d/fd", current_pid);
+    DIR* fd = opendir(buf);
+    if (!fd)
+      continue;
+
+    while ((dent = readdir(fd))) {
+      if (snprintf(buf, sizeof(buf), "/proc/%d/fd/%s", current_pid,
+                   dent->d_name) >= static_cast<int>(sizeof(buf))) {
+        continue;
+      }
+
+      ino_t fd_inode = static_cast<ino_t>(-1);
+      if (ProcPathGetInode(&fd_inode, buf)) {
+        if (fd_inode == socket_inode) {
+          if (already_found) {
+            closedir(fd);
+            return false;
+          }
+
+          already_found = true;
+          *pid_out = current_pid;
+          break;
+        }
+      }
+    }
+
+    closedir(fd);
+  }
+
+  return already_found;
+}
+
+pid_t FindThreadIDWithSyscall(pid_t pid, const std::string& expected_data,
+                              bool* syscall_supported) {
+  char buf[256];
+  snprintf(buf, sizeof(buf), "/proc/%d/task", pid);
+
+  if (syscall_supported != NULL)
+    *syscall_supported = false;
+
+  DIR* task = opendir(buf);
+  if (!task) {
+    DLOG(WARNING) << "Cannot open " << buf;
+    return -1;
+  }
+
+  std::vector<pid_t> tids;
+  struct dirent* dent;
+  while ((dent = readdir(task))) {
+    char* endptr;
+    const unsigned long int tid_ul = strtoul(dent->d_name, &endptr, 10);
+    if (tid_ul == ULONG_MAX || *endptr)
+      continue;
+    tids.push_back(tid_ul);
+  }
+  closedir(task);
+
+  scoped_ptr<char[]> syscall_data(new char[expected_data.length()]);
+  for (std::vector<pid_t>::const_iterator
+       i = tids.begin(); i != tids.end(); ++i) {
+    const pid_t current_tid = *i;
+    snprintf(buf, sizeof(buf), "/proc/%d/task/%d/syscall", pid, current_tid);
+    int fd = open(buf, O_RDONLY);
+    if (fd < 0)
+      continue;
+    if (syscall_supported != NULL)
+      *syscall_supported = true;
+    bool read_ret =
+        file_util::ReadFromFD(fd, syscall_data.get(), expected_data.length());
+    close(fd);
+    if (!read_ret)
+      continue;
+
+    if (0 == strncmp(expected_data.c_str(), syscall_data.get(),
+                     expected_data.length())) {
+      return current_tid;
+    }
+  }
+  return -1;
+}
+
+}  // namespace base