1// Ceres Solver - A fast non-linear least squares minimizer
2// Copyright 2010, 2011, 2012 Google Inc. All rights reserved.
3// http://code.google.com/p/ceres-solver/
4//
5// Redistribution and use in source and binary forms, with or without
6// modification, are permitted provided that the following conditions are met:
7//
8// * Redistributions of source code must retain the above copyright notice,
9//   this list of conditions and the following disclaimer.
10// * Redistributions in binary form must reproduce the above copyright notice,
11//   this list of conditions and the following disclaimer in the documentation
12//   and/or other materials provided with the distribution.
13// * Neither the name of Google Inc. nor the names of its contributors may be
14//   used to endorse or promote products derived from this software without
15//   specific prior written permission.
16//
17// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
18// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
21// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27// POSSIBILITY OF SUCH DAMAGE.
28//
29// Author: Sanjay Ghemawat
30
31#include "ceres/stringprintf.h"
32
33#include <cerrno>
34#include <cstdarg>  // For va_list and related operations
35#include <cstdio>   // MSVC requires this for _vsnprintf
36#include <string>
37#include <vector>
38
39#include "ceres/internal/port.h"
40
41namespace ceres {
42namespace internal {
43
44#ifdef _MSC_VER
45enum { IS_COMPILER_MSVC = 1 };
46#define va_copy(d,s) ((d) = (s))
47#else
48enum { IS_COMPILER_MSVC = 0 };
49#endif
50
51void StringAppendV(string* dst, const char* format, va_list ap) {
52  // First try with a small fixed size buffer
53  char space[1024];
54
55  // It's possible for methods that use a va_list to invalidate
56  // the data in it upon use.  The fix is to make a copy
57  // of the structure before using it and use that copy instead.
58  va_list backup_ap;
59  va_copy(backup_ap, ap);
60  int result = vsnprintf(space, sizeof(space), format, backup_ap);
61  va_end(backup_ap);
62
63  if (result < sizeof(space)) {
64    if (result >= 0) {
65      // Normal case -- everything fit.
66      dst->append(space, result);
67      return;
68    }
69
70    if (IS_COMPILER_MSVC) {
71      // Error or MSVC running out of space.  MSVC 8.0 and higher
72      // can be asked about space needed with the special idiom below:
73      va_copy(backup_ap, ap);
74      result = vsnprintf(NULL, 0, format, backup_ap);
75      va_end(backup_ap);
76    }
77
78    if (result < 0) {
79      // Just an error.
80      return;
81    }
82  }
83
84  // Increase the buffer size to the size requested by vsnprintf,
85  // plus one for the closing \0.
86  int length = result+1;
87  char* buf = new char[length];
88
89  // Restore the va_list before we use it again
90  va_copy(backup_ap, ap);
91  result = vsnprintf(buf, length, format, backup_ap);
92  va_end(backup_ap);
93
94  if (result >= 0 && result < length) {
95    // It fit
96    dst->append(buf, result);
97  }
98  delete[] buf;
99}
100
101
102string StringPrintf(const char* format, ...) {
103  va_list ap;
104  va_start(ap, format);
105  string result;
106  StringAppendV(&result, format, ap);
107  va_end(ap);
108  return result;
109}
110
111const string& SStringPrintf(string* dst, const char* format, ...) {
112  va_list ap;
113  va_start(ap, format);
114  dst->clear();
115  StringAppendV(dst, format, ap);
116  va_end(ap);
117  return *dst;
118}
119
120void StringAppendF(string* dst, const char* format, ...) {
121  va_list ap;
122  va_start(ap, format);
123  StringAppendV(dst, format, ap);
124  va_end(ap);
125}
126
127}  // namespace internal
128}  // namespace ceres
129