1a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// Protocol Buffers - Google's data interchange format
2a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// Copyright 2012 Google Inc.  All rights reserved.
3afb4b72037e3f13db208590fc782c4bc8e27f862Jeff Davidson// https://developers.google.com/protocol-buffers/
4a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson//
5a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// Redistribution and use in source and binary forms, with or without
6a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// modification, are permitted provided that the following conditions are
7a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// met:
8a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson//
9a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson//     * Redistributions of source code must retain the above copyright
10a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// notice, this list of conditions and the following disclaimer.
11a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson//     * Redistributions in binary form must reproduce the above
12a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// copyright notice, this list of conditions and the following disclaimer
13a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// in the documentation and/or other materials provided with the
14a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// distribution.
15a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson//     * Neither the name of Google Inc. nor the names of its
16a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// contributors may be used to endorse or promote products derived from
17a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// this software without specific prior written permission.
18a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson//
19a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
31a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// from google3/base/stringprintf.cc
32a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
33a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson#include <google/protobuf/stubs/stringprintf.h>
34a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
35a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson#include <errno.h>
36a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson#include <stdarg.h> // For va_list and related operations
37a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson#include <stdio.h> // MSVC requires this for _vsnprintf
38a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson#include <vector>
39a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson#include <google/protobuf/stubs/common.h>
40a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson#include <google/protobuf/testing/googletest.h>
41a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
42a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidsonnamespace google {
43a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidsonnamespace protobuf {
44a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
45a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson#ifdef _MSC_VER
46a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidsonenum { IS_COMPILER_MSVC = 1 };
47a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson#ifndef va_copy
48a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// Define va_copy for MSVC. This is a hack, assuming va_list is simply a
49a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// pointer into the stack and is safe to copy.
50a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson#define va_copy(dest, src) ((dest) = (src))
51a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson#endif
52a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson#else
53a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidsonenum { IS_COMPILER_MSVC = 0 };
54a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson#endif
55a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
56a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidsonvoid StringAppendV(string* dst, const char* format, va_list ap) {
57a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  // First try with a small fixed size buffer
58a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  static const int kSpaceLength = 1024;
59a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  char space[kSpaceLength];
60a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
61a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  // It's possible for methods that use a va_list to invalidate
62a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  // the data in it upon use.  The fix is to make a copy
63a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  // of the structure before using it and use that copy instead.
64a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  va_list backup_ap;
65a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  va_copy(backup_ap, ap);
66a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  int result = vsnprintf(space, kSpaceLength, format, backup_ap);
67a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  va_end(backup_ap);
68a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
69a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  if (result < kSpaceLength) {
70a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson    if (result >= 0) {
71a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson      // Normal case -- everything fit.
72a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson      dst->append(space, result);
73a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson      return;
74a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson    }
75a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
76a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson    if (IS_COMPILER_MSVC) {
77a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson      // Error or MSVC running out of space.  MSVC 8.0 and higher
78a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson      // can be asked about space needed with the special idiom below:
79a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson      va_copy(backup_ap, ap);
80a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson      result = vsnprintf(NULL, 0, format, backup_ap);
81a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson      va_end(backup_ap);
82a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson    }
83a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
84a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson    if (result < 0) {
85a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson      // Just an error.
86a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson      return;
87a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson    }
88a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  }
89a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
90a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  // Increase the buffer size to the size requested by vsnprintf,
91a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  // plus one for the closing \0.
92a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  int length = result+1;
93a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  char* buf = new char[length];
94a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
95a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  // Restore the va_list before we use it again
96a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  va_copy(backup_ap, ap);
97a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  result = vsnprintf(buf, length, format, backup_ap);
98a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  va_end(backup_ap);
99a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
100a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  if (result >= 0 && result < length) {
101a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson    // It fit
102a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson    dst->append(buf, result);
103a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  }
104a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  delete[] buf;
105a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson}
106a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
107a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
108a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidsonstring StringPrintf(const char* format, ...) {
109a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  va_list ap;
110a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  va_start(ap, format);
111a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  string result;
112a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  StringAppendV(&result, format, ap);
113a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  va_end(ap);
114a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  return result;
115a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson}
116a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
117a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidsonconst string& SStringPrintf(string* dst, const char* format, ...) {
118a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  va_list ap;
119a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  va_start(ap, format);
120a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  dst->clear();
121a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  StringAppendV(dst, format, ap);
122a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  va_end(ap);
123a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  return *dst;
124a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson}
125a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
126a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidsonvoid StringAppendF(string* dst, const char* format, ...) {
127a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  va_list ap;
128a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  va_start(ap, format);
129a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  StringAppendV(dst, format, ap);
130a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  va_end(ap);
131a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson}
132a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
133a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// Max arguments supported by StringPrintVector
134a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidsonconst int kStringPrintfVectorMaxArgs = 32;
135a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
136a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// An empty block of zero for filler arguments.  This is const so that if
137a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// printf tries to write to it (via %n) then the program gets a SIGSEGV
138a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson// and we can fix the problem or protect against an attack.
139a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidsonstatic const char string_printf_empty_block[256] = { '\0' };
140a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
141a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidsonstring StringPrintfVector(const char* format, const vector<string>& v) {
142a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  GOOGLE_CHECK_LE(v.size(), kStringPrintfVectorMaxArgs)
143a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson      << "StringPrintfVector currently only supports up to "
144a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson      << kStringPrintfVectorMaxArgs << " arguments. "
145a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson      << "Feel free to add support for more if you need it.";
146a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
147a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  // Add filler arguments so that bogus format+args have a harder time
148a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  // crashing the program, corrupting the program (%n),
149a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  // or displaying random chunks of memory to users.
150a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
151a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  const char* cstr[kStringPrintfVectorMaxArgs];
152a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  for (int i = 0; i < v.size(); ++i) {
153a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson    cstr[i] = v[i].c_str();
154a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  }
155a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  for (int i = v.size(); i < GOOGLE_ARRAYSIZE(cstr); ++i) {
156a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson    cstr[i] = &string_printf_empty_block[0];
157a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  }
158a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
159a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  // I do not know any way to pass kStringPrintfVectorMaxArgs arguments,
160a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  // or any way to build a va_list by hand, or any API for printf
161a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  // that accepts an array of arguments.  The best I can do is stick
162a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  // this COMPILE_ASSERT right next to the actual statement.
163a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson
164a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  GOOGLE_COMPILE_ASSERT(kStringPrintfVectorMaxArgs == 32, arg_count_mismatch);
165a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson  return StringPrintf(format,
166a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson                      cstr[0], cstr[1], cstr[2], cstr[3], cstr[4],
167a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson                      cstr[5], cstr[6], cstr[7], cstr[8], cstr[9],
168a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson                      cstr[10], cstr[11], cstr[12], cstr[13], cstr[14],
169a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson                      cstr[15], cstr[16], cstr[17], cstr[18], cstr[19],
170a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson                      cstr[20], cstr[21], cstr[22], cstr[23], cstr[24],
171a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson                      cstr[25], cstr[26], cstr[27], cstr[28], cstr[29],
172a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson                      cstr[30], cstr[31]);
173a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson}
174a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson}  // namespace protobuf
175a3b2a6da25a76f17c73d31def3952feb0fd2296eJeff Davidson}  // namespace google
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