Create LongStringDictionary and replace SimpleStringDictionary on iOS

This relands fd0a0d2b7ae9dd3d8a02b6a12e7941f7189fbb6c which was reverted
in 5dad29423e62292c6ff468cabfee4422ba55b18b, with a fix for guarding
kMaxSuffixLength which only used in assert()s with macros which breaks
chromium.mac/ios-device.

Change-Id: I5ee21b7f290517d6e7a0ef90b693b97f92392549
Reviewed-on: https://chromium-review.googlesource.com/751922
Reviewed-by: Mark Mentovai <mark@chromium.org>

1 files changed, 87 insertions, 0 deletions

diff --git a/src/common/long_string_dictionary.h b/src/common/long_string_dictionary.h
new file mode 100644
index 00000000..68bf03de
--- /dev/null
+++ b/src/common/long_string_dictionary.h
@@ -0,0 +1,87 @@
+// Copyright (c) 2017, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#ifndef COMMON_LONG_STRING_DICTIONARY_H_
+#define COMMON_LONG_STRING_DICTIONARY_H_
+
+#include <string>
+
+#include "common/simple_string_dictionary.h"
+
+namespace google_breakpad {
+// key_size is the maxium size that |key| can take in
+// SimpleStringDictionary which is defined in simple_string_dictionary.h.
+//
+// value_size is the maxium size that |value| can take in
+// SimpleStringDictionary which is defined in simple_string_dictionary.h.
+//
+// LongStringDictionary is a subclass of SimpleStringDictionary which supports
+// longer values to be stored in the dictionary. The maximum length supported is
+// (value_size - 1) * 10.
+//
+// For example, LongStringDictionary will store long value with key 'abc' into
+// segment values with segment keys 'abc__1', 'abc__2', 'abc__3', ...
+//
+// Clients must avoid using the same suffixes as their key's suffix when
+// LongStringDictionary is used.
+class LongStringDictionary : public SimpleStringDictionary {
+ public:
+  // Stores |value| into |key|, or segment values into segment keys. The maxium
+  // number of segments is 10. If |value| can not be stored in 10 segments, it
+  // will be truncated. Replacing the existing value if |key| is already present
+  // and replacing the existing segment values if segment keys are already
+  // present.
+  //
+  // |key| must not be NULL. If the |value| need to be divided into segments,
+  // the lengh of |key| must be smaller enough so that lengths of segment keys
+  // which are key with suffixes are all samller than (key_size - 1). Currently,
+  // the max length of suffixes are 4.
+  //
+  // If |value| is NULL, the key and its corresponding segment keys are removed
+  // from the map. If there is no more space in the map, then the operation
+  // silently fails.
+  void SetKeyValue(const char* key, const char* value);
+
+  // Given |key|, removes any associated value or associated segment values.
+  // |key| must not be NULL. If the key is not found, searchs its segment keys
+  // and removes corresponding segment values if found.
+  bool RemoveKey(const char* key);
+
+  // Given |key|, returns its corresponding |value|. |key| must not be NULL. If
+  // the key is found, its corresponding |value| is returned.
+  //
+  // If no corresponding |value| is found, segment keys of the given |key| will
+  // be used to search for corresponding segment values. If segment values
+  // exist, assembled value from them is returned. If no segment value exists,
+  // NULL is returned.
+  const std::string GetValueForKey(const char* key) const;
+};
+} // namespace google_breakpad
+
+#endif // COMMON_LONG_STRING_DICTIONARY_H_