1// Copyright (c) 2005, Google Inc.
2// All rights reserved.
3//
4// Redistribution and use in source and binary forms, with or without
5// modification, are permitted provided that the following conditions are
6// met:
7//
8//     * Redistributions of source code must retain the above copyright
9// notice, this list of conditions and the following disclaimer.
10//     * Redistributions in binary form must reproduce the above
11// copyright notice, this list of conditions and the following disclaimer
12// in the documentation and/or other materials provided with the
13// distribution.
14//     * Neither the name of Google Inc. nor the names of its
15// contributors may be used to endorse or promote products derived from
16// this software without specific prior written permission.
17//
18// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29
30// ---
31// Sanjay Ghemawat <opensource@google.com>
32
33#include <config.h>
34#include "internal_logging.h"
35#include <stdarg.h>                     // for va_end, va_start
36#include <stdio.h>                      // for vsnprintf, va_list, etc
37#include <stdlib.h>                     // for abort
38#include <string.h>                     // for strlen, memcpy
39#ifdef HAVE_UNISTD_H
40#include <unistd.h>    // for write()
41#endif
42
43#include <gperftools/malloc_extension.h>
44#include "base/logging.h"   // for perftools_vsnprintf
45#include "base/spinlock.h"              // for SpinLockHolder, SpinLock
46
47static const int kLogBufSize = 800;
48
49// Variables for storing crash output.  Allocated statically since we
50// may not be able to heap-allocate while crashing.
51static SpinLock crash_lock(base::LINKER_INITIALIZED);
52static bool crashed = false;
53static const int kStatsBufferSize = 16 << 10;
54static char stats_buffer[kStatsBufferSize] = { 0 };
55
56namespace tcmalloc {
57
58static void WriteMessage(const char* msg, int length) {
59  write(STDERR_FILENO, msg, length);
60}
61
62void (*log_message_writer)(const char* msg, int length) = WriteMessage;
63
64
65class Logger {
66 public:
67  bool Add(const LogItem& item);
68  bool AddStr(const char* str, int n);
69  bool AddNum(uint64_t num, int base);  // base must be 10 or 16.
70
71  static const int kBufSize = 200;
72  char* p_;
73  char* end_;
74  char buf_[kBufSize];
75};
76
77void Log(LogMode mode, const char* filename, int line,
78         LogItem a, LogItem b, LogItem c, LogItem d) {
79  Logger state;
80  state.p_ = state.buf_;
81  state.end_ = state.buf_ + sizeof(state.buf_);
82  state.AddStr(filename, strlen(filename))
83      && state.AddStr(":", 1)
84      && state.AddNum(line, 10)
85      && state.AddStr("]", 1)
86      && state.Add(a)
87      && state.Add(b)
88      && state.Add(c)
89      && state.Add(d);
90
91  // Teminate with newline
92  if (state.p_ >= state.end_) {
93    state.p_ = state.end_ - 1;
94  }
95  *state.p_ = '\n';
96  state.p_++;
97
98  int msglen = state.p_ - state.buf_;
99  if (mode == kLog) {
100    (*log_message_writer)(state.buf_, msglen);
101    return;
102  }
103
104  bool first_crash = false;
105  {
106    SpinLockHolder l(&crash_lock);
107    if (!crashed) {
108      crashed = true;
109      first_crash = true;
110    }
111  }
112
113  (*log_message_writer)(state.buf_, msglen);
114  if (first_crash && mode == kCrashWithStats) {
115    MallocExtension::instance()->GetStats(stats_buffer, kStatsBufferSize);
116    (*log_message_writer)(stats_buffer, strlen(stats_buffer));
117  }
118
119  abort();
120}
121
122bool Logger::Add(const LogItem& item) {
123  // Separate items with spaces
124  if (p_ < end_) {
125    *p_ = ' ';
126    p_++;
127  }
128
129  switch (item.tag_) {
130    case LogItem::kStr:
131      return AddStr(item.u_.str, strlen(item.u_.str));
132    case LogItem::kUnsigned:
133      return AddNum(item.u_.unum, 10);
134    case LogItem::kSigned:
135      if (item.u_.snum < 0) {
136        // The cast to uint64_t is intentionally before the negation
137        // so that we do not attempt to negate -2^63.
138        return AddStr("-", 1)
139            && AddNum(- static_cast<uint64_t>(item.u_.snum), 10);
140      } else {
141        return AddNum(static_cast<uint64_t>(item.u_.snum), 10);
142      }
143    case LogItem::kPtr:
144      return AddStr("0x", 2)
145          && AddNum(reinterpret_cast<uintptr_t>(item.u_.ptr), 16);
146    default:
147      return false;
148  }
149}
150
151bool Logger::AddStr(const char* str, int n) {
152  if (end_ - p_ < n) {
153    return false;
154  } else {
155    memcpy(p_, str, n);
156    p_ += n;
157    return true;
158  }
159}
160
161bool Logger::AddNum(uint64_t num, int base) {
162  static const char kDigits[] = "0123456789abcdef";
163  char space[22];  // more than enough for 2^64 in smallest supported base (10)
164  char* end = space + sizeof(space);
165  char* pos = end;
166  do {
167    pos--;
168    *pos = kDigits[num % base];
169    num /= base;
170  } while (num > 0 && pos > space);
171  return AddStr(pos, end - pos);
172}
173
174}  // end tcmalloc namespace
175
176void TCMalloc_Printer::printf(const char* format, ...) {
177  if (left_ > 0) {
178    va_list ap;
179    va_start(ap, format);
180    const int r = perftools_vsnprintf(buf_, left_, format, ap);
181    va_end(ap);
182    if (r < 0) {
183      // Perhaps an old glibc that returns -1 on truncation?
184      left_ = 0;
185    } else if (r > left_) {
186      // Truncation
187      left_ = 0;
188    } else {
189      left_ -= r;
190      buf_ += r;
191    }
192  }
193}
194