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      1 // Copyright 2007, 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.
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     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
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     21 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     22 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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     24 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     25 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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     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 // Author: wan (at) google.com (Zhanyong Wan)
     31 
     32 // Google Test - The Google C++ Testing Framework
     33 //
     34 // This file implements a universal value printer that can print a
     35 // value of any type T:
     36 //
     37 //   void ::testing::internal::UniversalPrinter<T>::Print(value, ostream_ptr);
     38 //
     39 // It uses the << operator when possible, and prints the bytes in the
     40 // object otherwise.  A user can override its behavior for a class
     41 // type Foo by defining either operator<<(::std::ostream&, const Foo&)
     42 // or void PrintTo(const Foo&, ::std::ostream*) in the namespace that
     43 // defines Foo.
     44 
     45 #include "gtest/gtest-printers.h"
     46 #include <ctype.h>
     47 #include <stdio.h>
     48 #include <ostream>  // NOLINT
     49 #include <string>
     50 #include "gtest/internal/gtest-port.h"
     51 
     52 namespace testing {
     53 
     54 namespace {
     55 
     56 using ::std::ostream;
     57 
     58 #if GTEST_OS_WINDOWS_MOBILE  // Windows CE does not define _snprintf_s.
     59 # define snprintf _snprintf
     60 #elif _MSC_VER >= 1400  // VC 8.0 and later deprecate snprintf and _snprintf.
     61 # define snprintf _snprintf_s
     62 #elif _MSC_VER
     63 # define snprintf _snprintf
     64 #endif  // GTEST_OS_WINDOWS_MOBILE
     65 
     66 // Prints a segment of bytes in the given object.
     67 void PrintByteSegmentInObjectTo(const unsigned char* obj_bytes, size_t start,
     68                                 size_t count, ostream* os) {
     69   char text[5] = "";
     70   for (size_t i = 0; i != count; i++) {
     71     const size_t j = start + i;
     72     if (i != 0) {
     73       // Organizes the bytes into groups of 2 for easy parsing by
     74       // human.
     75       if ((j % 2) == 0)
     76         *os << ' ';
     77       else
     78         *os << '-';
     79     }
     80     snprintf(text, sizeof(text), "%02X", obj_bytes[j]);
     81     *os << text;
     82   }
     83 }
     84 
     85 // Prints the bytes in the given value to the given ostream.
     86 void PrintBytesInObjectToImpl(const unsigned char* obj_bytes, size_t count,
     87                               ostream* os) {
     88   // Tells the user how big the object is.
     89   *os << count << "-byte object <";
     90 
     91   const size_t kThreshold = 132;
     92   const size_t kChunkSize = 64;
     93   // If the object size is bigger than kThreshold, we'll have to omit
     94   // some details by printing only the first and the last kChunkSize
     95   // bytes.
     96   // TODO(wan): let the user control the threshold using a flag.
     97   if (count < kThreshold) {
     98     PrintByteSegmentInObjectTo(obj_bytes, 0, count, os);
     99   } else {
    100     PrintByteSegmentInObjectTo(obj_bytes, 0, kChunkSize, os);
    101     *os << " ... ";
    102     // Rounds up to 2-byte boundary.
    103     const size_t resume_pos = (count - kChunkSize + 1)/2*2;
    104     PrintByteSegmentInObjectTo(obj_bytes, resume_pos, count - resume_pos, os);
    105   }
    106   *os << ">";
    107 }
    108 
    109 }  // namespace
    110 
    111 namespace internal2 {
    112 
    113 // Delegates to PrintBytesInObjectToImpl() to print the bytes in the
    114 // given object.  The delegation simplifies the implementation, which
    115 // uses the << operator and thus is easier done outside of the
    116 // ::testing::internal namespace, which contains a << operator that
    117 // sometimes conflicts with the one in STL.
    118 void PrintBytesInObjectTo(const unsigned char* obj_bytes, size_t count,
    119                           ostream* os) {
    120   PrintBytesInObjectToImpl(obj_bytes, count, os);
    121 }
    122 
    123 }  // namespace internal2
    124 
    125 namespace internal {
    126 
    127 // Depending on the value of a char (or wchar_t), we print it in one
    128 // of three formats:
    129 //   - as is if it's a printable ASCII (e.g. 'a', '2', ' '),
    130 //   - as a hexidecimal escape sequence (e.g. '\x7F'), or
    131 //   - as a special escape sequence (e.g. '\r', '\n').
    132 enum CharFormat {
    133   kAsIs,
    134   kHexEscape,
    135   kSpecialEscape
    136 };
    137 
    138 // Returns true if c is a printable ASCII character.  We test the
    139 // value of c directly instead of calling isprint(), which is buggy on
    140 // Windows Mobile.
    141 static inline bool IsPrintableAscii(wchar_t c) {
    142   return 0x20 <= c && c <= 0x7E;
    143 }
    144 
    145 // Prints a wide or narrow char c as a character literal without the
    146 // quotes, escaping it when necessary; returns how c was formatted.
    147 // The template argument UnsignedChar is the unsigned version of Char,
    148 // which is the type of c.
    149 template <typename UnsignedChar, typename Char>
    150 static CharFormat PrintAsCharLiteralTo(Char c, ostream* os) {
    151   switch (static_cast<wchar_t>(c)) {
    152     case L'\0':
    153       *os << "\\0";
    154       break;
    155     case L'\'':
    156       *os << "\\'";
    157       break;
    158     case L'\\':
    159       *os << "\\\\";
    160       break;
    161     case L'\a':
    162       *os << "\\a";
    163       break;
    164     case L'\b':
    165       *os << "\\b";
    166       break;
    167     case L'\f':
    168       *os << "\\f";
    169       break;
    170     case L'\n':
    171       *os << "\\n";
    172       break;
    173     case L'\r':
    174       *os << "\\r";
    175       break;
    176     case L'\t':
    177       *os << "\\t";
    178       break;
    179     case L'\v':
    180       *os << "\\v";
    181       break;
    182     default:
    183       if (IsPrintableAscii(c)) {
    184         *os << static_cast<char>(c);
    185         return kAsIs;
    186       } else {
    187         *os << String::Format("\\x%X", static_cast<UnsignedChar>(c));
    188         return kHexEscape;
    189       }
    190   }
    191   return kSpecialEscape;
    192 }
    193 
    194 // Prints a char c as if it's part of a string literal, escaping it when
    195 // necessary; returns how c was formatted.
    196 static CharFormat PrintAsWideStringLiteralTo(wchar_t c, ostream* os) {
    197   switch (c) {
    198     case L'\'':
    199       *os << "'";
    200       return kAsIs;
    201     case L'"':
    202       *os << "\\\"";
    203       return kSpecialEscape;
    204     default:
    205       return PrintAsCharLiteralTo<wchar_t>(c, os);
    206   }
    207 }
    208 
    209 // Prints a char c as if it's part of a string literal, escaping it when
    210 // necessary; returns how c was formatted.
    211 static CharFormat PrintAsNarrowStringLiteralTo(char c, ostream* os) {
    212   return PrintAsWideStringLiteralTo(static_cast<unsigned char>(c), os);
    213 }
    214 
    215 // Prints a wide or narrow character c and its code.  '\0' is printed
    216 // as "'\\0'", other unprintable characters are also properly escaped
    217 // using the standard C++ escape sequence.  The template argument
    218 // UnsignedChar is the unsigned version of Char, which is the type of c.
    219 template <typename UnsignedChar, typename Char>
    220 void PrintCharAndCodeTo(Char c, ostream* os) {
    221   // First, print c as a literal in the most readable form we can find.
    222   *os << ((sizeof(c) > 1) ? "L'" : "'");
    223   const CharFormat format = PrintAsCharLiteralTo<UnsignedChar>(c, os);
    224   *os << "'";
    225 
    226   // To aid user debugging, we also print c's code in decimal, unless
    227   // it's 0 (in which case c was printed as '\\0', making the code
    228   // obvious).
    229   if (c == 0)
    230     return;
    231   *os << " (" << String::Format("%d", c).c_str();
    232 
    233   // For more convenience, we print c's code again in hexidecimal,
    234   // unless c was already printed in the form '\x##' or the code is in
    235   // [1, 9].
    236   if (format == kHexEscape || (1 <= c && c <= 9)) {
    237     // Do nothing.
    238   } else {
    239     *os << String::Format(", 0x%X",
    240                           static_cast<UnsignedChar>(c)).c_str();
    241   }
    242   *os << ")";
    243 }
    244 
    245 void PrintTo(unsigned char c, ::std::ostream* os) {
    246   PrintCharAndCodeTo<unsigned char>(c, os);
    247 }
    248 void PrintTo(signed char c, ::std::ostream* os) {
    249   PrintCharAndCodeTo<unsigned char>(c, os);
    250 }
    251 
    252 // Prints a wchar_t as a symbol if it is printable or as its internal
    253 // code otherwise and also as its code.  L'\0' is printed as "L'\\0'".
    254 void PrintTo(wchar_t wc, ostream* os) {
    255   PrintCharAndCodeTo<wchar_t>(wc, os);
    256 }
    257 
    258 // Prints the given array of characters to the ostream.
    259 // The array starts at *begin, the length is len, it may include '\0' characters
    260 // and may not be null-terminated.
    261 static void PrintCharsAsStringTo(const char* begin, size_t len, ostream* os) {
    262   *os << "\"";
    263   bool is_previous_hex = false;
    264   for (size_t index = 0; index < len; ++index) {
    265     const char cur = begin[index];
    266     if (is_previous_hex && IsXDigit(cur)) {
    267       // Previous character is of '\x..' form and this character can be
    268       // interpreted as another hexadecimal digit in its number. Break string to
    269       // disambiguate.
    270       *os << "\" \"";
    271     }
    272     is_previous_hex = PrintAsNarrowStringLiteralTo(cur, os) == kHexEscape;
    273   }
    274   *os << "\"";
    275 }
    276 
    277 // Prints a (const) char array of 'len' elements, starting at address 'begin'.
    278 void UniversalPrintArray(const char* begin, size_t len, ostream* os) {
    279   PrintCharsAsStringTo(begin, len, os);
    280 }
    281 
    282 // Prints the given array of wide characters to the ostream.
    283 // The array starts at *begin, the length is len, it may include L'\0'
    284 // characters and may not be null-terminated.
    285 static void PrintWideCharsAsStringTo(const wchar_t* begin, size_t len,
    286                                      ostream* os) {
    287   *os << "L\"";
    288   bool is_previous_hex = false;
    289   for (size_t index = 0; index < len; ++index) {
    290     const wchar_t cur = begin[index];
    291     if (is_previous_hex && 0 <= cur && cur < 128 &&
    292         IsXDigit(static_cast<char>(cur))) {
    293       // Previous character is of '\x..' form and this character can be
    294       // interpreted as another hexadecimal digit in its number. Break string to
    295       // disambiguate.
    296       *os << "\" L\"";
    297     }
    298     is_previous_hex = PrintAsWideStringLiteralTo(cur, os) == kHexEscape;
    299   }
    300   *os << "\"";
    301 }
    302 
    303 // Prints the given C string to the ostream.
    304 void PrintTo(const char* s, ostream* os) {
    305   if (s == NULL) {
    306     *os << "NULL";
    307   } else {
    308     *os << ImplicitCast_<const void*>(s) << " pointing to ";
    309     PrintCharsAsStringTo(s, strlen(s), os);
    310   }
    311 }
    312 
    313 // MSVC compiler can be configured to define whar_t as a typedef
    314 // of unsigned short. Defining an overload for const wchar_t* in that case
    315 // would cause pointers to unsigned shorts be printed as wide strings,
    316 // possibly accessing more memory than intended and causing invalid
    317 // memory accesses. MSVC defines _NATIVE_WCHAR_T_DEFINED symbol when
    318 // wchar_t is implemented as a native type.
    319 #if !defined(_MSC_VER) || defined(_NATIVE_WCHAR_T_DEFINED)
    320 // Prints the given wide C string to the ostream.
    321 void PrintTo(const wchar_t* s, ostream* os) {
    322   if (s == NULL) {
    323     *os << "NULL";
    324   } else {
    325     *os << ImplicitCast_<const void*>(s) << " pointing to ";
    326     PrintWideCharsAsStringTo(s, wcslen(s), os);
    327   }
    328 }
    329 #endif  // wchar_t is native
    330 
    331 // Prints a ::string object.
    332 #if GTEST_HAS_GLOBAL_STRING
    333 void PrintStringTo(const ::string& s, ostream* os) {
    334   PrintCharsAsStringTo(s.data(), s.size(), os);
    335 }
    336 #endif  // GTEST_HAS_GLOBAL_STRING
    337 
    338 void PrintStringTo(const ::std::string& s, ostream* os) {
    339   PrintCharsAsStringTo(s.data(), s.size(), os);
    340 }
    341 
    342 // Prints a ::wstring object.
    343 #if GTEST_HAS_GLOBAL_WSTRING
    344 void PrintWideStringTo(const ::wstring& s, ostream* os) {
    345   PrintWideCharsAsStringTo(s.data(), s.size(), os);
    346 }
    347 #endif  // GTEST_HAS_GLOBAL_WSTRING
    348 
    349 #if GTEST_HAS_STD_WSTRING
    350 void PrintWideStringTo(const ::std::wstring& s, ostream* os) {
    351   PrintWideCharsAsStringTo(s.data(), s.size(), os);
    352 }
    353 #endif  // GTEST_HAS_STD_WSTRING
    354 
    355 }  // namespace internal
    356 
    357 }  // namespace testing
    358