1 // Copyright (c) 2011 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 // This file defines utility functions for escaping strings suitable for JSON. 6 7 #ifndef BASE_JSON_STRING_ESCAPE_H_ 8 #define BASE_JSON_STRING_ESCAPE_H_ 9 10 #include <string> 11 12 #include "base/base_export.h" 13 #include "base/strings/string_piece.h" 14 15 namespace base { 16 17 // Appends to |dest| an escaped version of |str|. Valid UTF-8 code units will 18 // pass through from the input to the output. Invalid code units will be 19 // replaced with the U+FFFD replacement character. This function returns true 20 // if no replacement was necessary and false if there was a lossy replacement. 21 // On return, |dest| will contain a valid UTF-8 JSON string. 22 // 23 // Non-printing control characters will be escaped as \uXXXX sequences for 24 // readability. 25 // 26 // If |put_in_quotes| is true, then a leading and trailing double-quote mark 27 // will be appended to |dest| as well. 28 BASE_EXPORT bool EscapeJSONString(const StringPiece& str, 29 bool put_in_quotes, 30 std::string* dest); 31 32 // Performs a similar function to the UTF-8 StringPiece version above, 33 // converting UTF-16 code units to UTF-8 code units and escaping non-printing 34 // control characters. On return, |dest| will contain a valid UTF-8 JSON string. 35 BASE_EXPORT bool EscapeJSONString(const StringPiece16& str, 36 bool put_in_quotes, 37 std::string* dest); 38 39 // Helper functions that wrap the above two functions but return the value 40 // instead of appending. |put_in_quotes| is always true. 41 BASE_EXPORT std::string GetQuotedJSONString(const StringPiece& str); 42 BASE_EXPORT std::string GetQuotedJSONString(const StringPiece16& str); 43 44 // Given an arbitrary byte string |str|, this will escape all non-ASCII bytes 45 // as \uXXXX escape sequences. This function is *NOT* meant to be used with 46 // Unicode strings and does not validate |str| as one. 47 // 48 // CAVEAT CALLER: The output of this function may not be valid JSON, since 49 // JSON requires escape sequences to be valid UTF-16 code units. This output 50 // will be mangled if passed to to the base::JSONReader, since the reader will 51 // interpret it as UTF-16 and convert it to UTF-8. 52 // 53 // The output of this function takes the *appearance* of JSON but is not in 54 // fact valid according to RFC 4627. 55 BASE_EXPORT std::string EscapeBytesAsInvalidJSONString(const StringPiece& str, 56 bool put_in_quotes); 57 58 } // namespace base 59 60 #endif // BASE_JSON_STRING_ESCAPE_H_ 61