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 
41 namespace ceres {
42 namespace internal {
43 
44 #ifdef _MSC_VER
45 enum { IS_COMPILER_MSVC = 1 };
46 #if _MSC_VER < 1800
47 #define va_copy(d, s) ((d) = (s))
48 #endif
49 #else
50 enum { IS_COMPILER_MSVC = 0 };
51 #endif
52 
StringAppendV(string * dst,const char * format,va_list ap)53 void StringAppendV(string* dst, const char* format, va_list ap) {
54   // First try with a small fixed size buffer
55   char space[1024];
56 
57   // It's possible for methods that use a va_list to invalidate
58   // the data in it upon use.  The fix is to make a copy
59   // of the structure before using it and use that copy instead.
60   va_list backup_ap;
61   va_copy(backup_ap, ap);
62   int result = vsnprintf(space, sizeof(space), format, backup_ap);
63   va_end(backup_ap);
64 
65   if (result < sizeof(space)) {
66     if (result >= 0) {
67       // Normal case -- everything fit.
68       dst->append(space, result);
69       return;
70     }
71 
72     if (IS_COMPILER_MSVC) {
73       // Error or MSVC running out of space.  MSVC 8.0 and higher
74       // can be asked about space needed with the special idiom below:
75       va_copy(backup_ap, ap);
76       result = vsnprintf(NULL, 0, format, backup_ap);
77       va_end(backup_ap);
78     }
79 
80     if (result < 0) {
81       // Just an error.
82       return;
83     }
84   }
85 
86   // Increase the buffer size to the size requested by vsnprintf,
87   // plus one for the closing \0.
88   int length = result+1;
89   char* buf = new char[length];
90 
91   // Restore the va_list before we use it again
92   va_copy(backup_ap, ap);
93   result = vsnprintf(buf, length, format, backup_ap);
94   va_end(backup_ap);
95 
96   if (result >= 0 && result < length) {
97     // It fit
98     dst->append(buf, result);
99   }
100   delete[] buf;
101 }
102 
103 
StringPrintf(const char * format,...)104 string StringPrintf(const char* format, ...) {
105   va_list ap;
106   va_start(ap, format);
107   string result;
108   StringAppendV(&result, format, ap);
109   va_end(ap);
110   return result;
111 }
112 
SStringPrintf(string * dst,const char * format,...)113 const string& SStringPrintf(string* dst, const char* format, ...) {
114   va_list ap;
115   va_start(ap, format);
116   dst->clear();
117   StringAppendV(dst, format, ap);
118   va_end(ap);
119   return *dst;
120 }
121 
StringAppendF(string * dst,const char * format,...)122 void StringAppendF(string* dst, const char* format, ...) {
123   va_list ap;
124   va_start(ap, format);
125   StringAppendV(dst, format, ap);
126   va_end(ap);
127 }
128 
129 }  // namespace internal
130 }  // namespace ceres
131