1  // Copyright 2017 Google LLC
  2  //
  3  // Redistribution and use in source and binary forms, with or without
  4  // modification, are permitted provided that the following conditions are
  5  // met:
  6  //
  7  //     * Redistributions of source code must retain the above copyright
  8  // notice, this list of conditions and the following disclaimer.
  9  //     * Redistributions in binary form must reproduce the above
 10  // copyright notice, this list of conditions and the following disclaimer
 11  // in the documentation and/or other materials provided with the
 12  // distribution.
 13  //     * Neither the name of Google LLC nor the names of its
 14  // contributors may be used to endorse or promote products derived from
 15  // this software without specific prior written permission.
 16  //
 17  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 18  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 19  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 20  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 21  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 22  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 23  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 24  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 25  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 26  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 27  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 28  
 29  #ifdef HAVE_CONFIG_H
 30  #include <config.h>  // Must come first
 31  #endif
 32  
 33  #include "common/long_string_dictionary.h"
 34  
 35  #include <assert.h>
 36  #include <string.h>
 37  
 38  #include <algorithm>
 39  #include <string>
 40  
 41  #include "common/simple_string_dictionary.h"
 42  
 43  #define arraysize(f) (sizeof(f) / sizeof(*f))
 44  
 45  namespace {
 46  // Suffixes for segment keys.
 47  const char* const kSuffixes[] = {"__1", "__2", "__3", "__4", "__5", "__6",
 48      "__7", "__8", "__9", "__10"};
 49  #if !defined(NDEBUG)
 50  // The maximum suffix string length.
 51  const size_t kMaxSuffixLength = 4;
 52  #endif
 53  } // namespace
 54  
 55  namespace google_breakpad {
 56  
 57  using std::string;
 58  
 59  void LongStringDictionary::SetKeyValue(const char* key, const char* value) {
 60    assert(key);
 61    if (!key)
 62      return;
 63  
 64    RemoveKey(key);
 65  
 66    if (!value) {
 67      return;
 68    }
 69  
 70    // Key must not be an empty string.
 71    assert(key[0] != '\0');
 72    if (key[0] == '\0')
 73      return;
 74  
 75    // If the value is not valid for segmentation, forwards the key and the value
 76    // to SetKeyValue of SimpleStringDictionary and returns.
 77    size_t value_length = strlen(value);
 78    if (value_length <= (value_size - 1)) {
 79      SimpleStringDictionary::SetKeyValue(key, value);
 80      return;
 81    }
 82  
 83    size_t key_length = strlen(key);
 84    assert(key_length + kMaxSuffixLength <= (key_size - 1));
 85  
 86    char segment_key[key_size];
 87    char segment_value[value_size];
 88  
 89    strcpy(segment_key, key);
 90  
 91    const char* remain_value = value;
 92    size_t remain_value_length = strlen(value);
 93  
 94    for (unsigned long i = 0; i < arraysize(kSuffixes); i++) {
 95      if (remain_value_length == 0) {
 96        return;
 97      }
 98  
 99      strcpy(segment_key + key_length, kSuffixes[i]);
100  
101      size_t segment_value_length =
102          std::min(remain_value_length, value_size - 1);
103  
104      strncpy(segment_value, remain_value, segment_value_length);
105      segment_value[segment_value_length] = '\0';
106  
107      remain_value += segment_value_length;
108      remain_value_length -= segment_value_length;
109  
110      SimpleStringDictionary::SetKeyValue(segment_key, segment_value);
111    }
112  }
113  
114  bool LongStringDictionary::RemoveKey(const char* key) {
115    assert(key);
116    if (!key)
117      return false;
118  
119    if (SimpleStringDictionary::RemoveKey(key)) {
120      return true;
121    }
122  
123    size_t key_length = strlen(key);
124    assert(key_length + kMaxSuffixLength <= (key_size - 1));
125  
126    char segment_key[key_size];
127    strcpy(segment_key, key);
128  
129    unsigned long i = 0;
130    for (; i < arraysize(kSuffixes); i++) {
131      strcpy(segment_key + key_length, kSuffixes[i]);
132      if (!SimpleStringDictionary::RemoveKey(segment_key)) {
133        break;
134      }
135    }
136    return i != 0;
137  }
138  
139  const string LongStringDictionary::GetValueForKey(const char* key) const {
140    assert(key);
141    if (!key)
142      return "";
143  
144    // Key must not be an empty string.
145    assert(key[0] != '\0');
146    if (key[0] == '\0')
147      return "";
148  
149    const char* value = SimpleStringDictionary::GetValueForKey(key);
150    if (value)
151      return string(value);
152  
153    size_t key_length = strlen(key);
154    assert(key_length + kMaxSuffixLength <= (key_size - 1));
155  
156    bool found_segment = false;
157    char segment_key[key_size];
158    string return_value;
159  
160    strcpy(segment_key, key);
161    for (unsigned long i = 0; i < arraysize(kSuffixes); i++) {
162      strcpy(segment_key + key_length, kSuffixes[i]);
163  
164      const char* segment_value =
165          SimpleStringDictionary::GetValueForKey(segment_key);
166  
167      if (segment_value != NULL) {
168        found_segment = true;
169        return_value.append(segment_value);
170      } else {
171        break;
172      }
173    }
174  
175    if (found_segment) {
176      return return_value;
177    }
178    return "";
179  }
180  
181  }  // namespace google_breakpad