The Tor Browser: security/sandbox/chromium/base/strings/string

security/sandbox/chromium/base/strings/string_util.h@141e0f1194b1 (annotated)

security/sandbox/chromium/base/strings/string_util.h

Wed, 31 Dec 2014 07:16:47 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 07:16:47 +0100
branch: TOR_BUG_9701
changeset 3: 141e0f1194b1
permissions: -rw-r--r--

Revert simplistic fix pending revisit of Mozilla integration attempt.

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // This file defines utility functions for working with strings.
 #ifndef BASE_STRINGS_STRING_UTIL_H_
 #define BASE_STRINGS_STRING_UTIL_H_
 #include <ctype.h>
 #include <stdarg.h>   // va_list
 #include <string>
 #include <vector>
 #include "base/base_export.h"
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_piece.h"  // For implicit conversions.
 // Safe standard library wrappers for all platforms.
 namespace base {
 // C standard-library functions like "strncasecmp" and "snprintf" that aren't
 // cross-platform are provided as "base::strncasecmp", and their prototypes
 // are listed below.  These functions are then implemented as inline calls
 // to the platform-specific equivalents in the platform-specific headers.
 // Compares the two strings s1 and s2 without regard to case using
 // the current locale; returns 0 if they are equal, 1 if s1 > s2, and -1 if
 // s2 > s1 according to a lexicographic comparison.
 int strcasecmp(const char* s1, const char* s2);
 // Compares up to count characters of s1 and s2 without regard to case using
 // the current locale; returns 0 if they are equal, 1 if s1 > s2, and -1 if
 // s2 > s1 according to a lexicographic comparison.
 int strncasecmp(const char* s1, const char* s2, size_t count);
 // Same as strncmp but for char16 strings.
 int strncmp16(const char16* s1, const char16* s2, size_t count);
 // Wrapper for vsnprintf that always null-terminates and always returns the
 // number of characters that would be in an untruncated formatted
 // string, even when truncation occurs.
 int vsnprintf(char* buffer, size_t size, const char* format, va_list arguments)
     PRINTF_FORMAT(3, 0);
 // vswprintf always null-terminates, but when truncation occurs, it will either
 // return -1 or the number of characters that would be in an untruncated
 // formatted string.  The actual return value depends on the underlying
 // C library's vswprintf implementation.
 int vswprintf(wchar_t* buffer, size_t size,
               const wchar_t* format, va_list arguments)
     WPRINTF_FORMAT(3, 0);
 // Some of these implementations need to be inlined.
 // We separate the declaration from the implementation of this inline
 // function just so the PRINTF_FORMAT works.
 inline int snprintf(char* buffer, size_t size, const char* format, ...)
     PRINTF_FORMAT(3, 4);
 inline int snprintf(char* buffer, size_t size, const char* format, ...) {
   va_list arguments;
   va_start(arguments, format);
   int result = vsnprintf(buffer, size, format, arguments);
   va_end(arguments);
   return result;
 }
 // We separate the declaration from the implementation of this inline
 // function just so the WPRINTF_FORMAT works.
 inline int swprintf(wchar_t* buffer, size_t size, const wchar_t* format, ...)
     WPRINTF_FORMAT(3, 4);
 inline int swprintf(wchar_t* buffer, size_t size, const wchar_t* format, ...) {
   va_list arguments;
   va_start(arguments, format);
   int result = vswprintf(buffer, size, format, arguments);
   va_end(arguments);
   return result;
 }
 // BSD-style safe and consistent string copy functions.
 // Copies |src| to |dst|, where |dst_size| is the total allocated size of |dst|.
 // Copies at most |dst_size|-1 characters, and always NULL terminates |dst|, as
 // long as |dst_size| is not 0.  Returns the length of |src| in characters.
 // If the return value is >= dst_size, then the output was truncated.
 // NOTE: All sizes are in number of characters, NOT in bytes.
 BASE_EXPORT size_t strlcpy(char* dst, const char* src, size_t dst_size);
 BASE_EXPORT size_t wcslcpy(wchar_t* dst, const wchar_t* src, size_t dst_size);
 // Scan a wprintf format string to determine whether it's portable across a
 // variety of systems.  This function only checks that the conversion
 // specifiers used by the format string are supported and have the same meaning
 // on a variety of systems.  It doesn't check for other errors that might occur
 // within a format string.
 //
 // Nonportable conversion specifiers for wprintf are:
 //  - 's' and 'c' without an 'l' length modifier.  %s and %c operate on char
 //     data on all systems except Windows, which treat them as wchar_t data.
 //     Use %ls and %lc for wchar_t data instead.
 //  - 'S' and 'C', which operate on wchar_t data on all systems except Windows,
 //     which treat them as char data.  Use %ls and %lc for wchar_t data
 //     instead.
 //  - 'F', which is not identified by Windows wprintf documentation.
 //  - 'D', 'O', and 'U', which are deprecated and not available on all systems.
 //     Use %ld, %lo, and %lu instead.
 //
 // Note that there is no portable conversion specifier for char data when
 // working with wprintf.
 //
 // This function is intended to be called from base::vswprintf.
 BASE_EXPORT bool IsWprintfFormatPortable(const wchar_t* format);
 // ASCII-specific tolower.  The standard library's tolower is locale sensitive,
 // so we don't want to use it here.
 template <class Char> inline Char ToLowerASCII(Char c) {
   return (c >= 'A' && c <= 'Z') ? (c + ('a' - 'A')) : c;
 }
 // ASCII-specific toupper.  The standard library's toupper is locale sensitive,
 // so we don't want to use it here.
 template <class Char> inline Char ToUpperASCII(Char c) {
   return (c >= 'a' && c <= 'z') ? (c + ('A' - 'a')) : c;
 }
 // Function objects to aid in comparing/searching strings.
 template<typename Char> struct CaseInsensitiveCompare {
  public:
   bool operator()(Char x, Char y) const {
     // TODO(darin): Do we really want to do locale sensitive comparisons here?
     // See http://crbug.com/24917
     return tolower(x) == tolower(y);
   }
 };
 template<typename Char> struct CaseInsensitiveCompareASCII {
  public:
   bool operator()(Char x, Char y) const {
     return ToLowerASCII(x) == ToLowerASCII(y);
   }
 };
 }  // namespace base
 #if defined(OS_WIN)
 #include "base/strings/string_util_win.h"
 #elif defined(OS_POSIX)
 #include "base/strings/string_util_posix.h"
 #else
 #error Define string operations appropriately for your platform
 #endif
 // These threadsafe functions return references to globally unique empty
 // strings.
 //
 // DO NOT USE THESE AS A GENERAL-PURPOSE SUBSTITUTE FOR DEFAULT CONSTRUCTORS.
 // There is only one case where you should use these: functions which need to
 // return a string by reference (e.g. as a class member accessor), and don't
 // have an empty string to use (e.g. in an error case).  These should not be
 // used as initializers, function arguments, or return values for functions
 // which return by value or outparam.
 BASE_EXPORT const std::string& EmptyString();
 BASE_EXPORT const std::wstring& EmptyWString();
 BASE_EXPORT const string16& EmptyString16();
 BASE_EXPORT extern const wchar_t kWhitespaceWide[];
 BASE_EXPORT extern const char16 kWhitespaceUTF16[];
 BASE_EXPORT extern const char kWhitespaceASCII[];
 BASE_EXPORT extern const char kUtf8ByteOrderMark[];
 // Removes characters in |remove_chars| from anywhere in |input|.  Returns true
 // if any characters were removed.  |remove_chars| must be null-terminated.
 // NOTE: Safe to use the same variable for both |input| and |output|.
 BASE_EXPORT bool RemoveChars(const string16& input,
                              const char16 remove_chars[],
                              string16* output);
 BASE_EXPORT bool RemoveChars(const std::string& input,
                              const char remove_chars[],
                              std::string* output);
 // Replaces characters in |replace_chars| from anywhere in |input| with
 // |replace_with|.  Each character in |replace_chars| will be replaced with
 // the |replace_with| string.  Returns true if any characters were replaced.
 // |replace_chars| must be null-terminated.
 // NOTE: Safe to use the same variable for both |input| and |output|.
 BASE_EXPORT bool ReplaceChars(const string16& input,
                               const char16 replace_chars[],
                               const string16& replace_with,
                               string16* output);
 BASE_EXPORT bool ReplaceChars(const std::string& input,
                               const char replace_chars[],
                               const std::string& replace_with,
                               std::string* output);
 // Removes characters in |trim_chars| from the beginning and end of |input|.
 // |trim_chars| must be null-terminated.
 // NOTE: Safe to use the same variable for both |input| and |output|.
 BASE_EXPORT bool TrimString(const std::wstring& input,
                             const wchar_t trim_chars[],
                             std::wstring* output);
 BASE_EXPORT bool TrimString(const string16& input,
                             const char16 trim_chars[],
                             string16* output);
 BASE_EXPORT bool TrimString(const std::string& input,
                             const char trim_chars[],
                             std::string* output);
 // Truncates a string to the nearest UTF-8 character that will leave
 // the string less than or equal to the specified byte size.
 BASE_EXPORT void TruncateUTF8ToByteSize(const std::string& input,
                                         const size_t byte_size,
                                         std::string* output);
 // Trims any whitespace from either end of the input string.  Returns where
 // whitespace was found.
 // The non-wide version has two functions:
 // * TrimWhitespaceASCII()
 //   This function is for ASCII strings and only looks for ASCII whitespace;
 // Please choose the best one according to your usage.
 // NOTE: Safe to use the same variable for both input and output.
 enum TrimPositions {
   TRIM_NONE     = 0,
   TRIM_LEADING  = 1 << 0,
   TRIM_TRAILING = 1 << 1,
   TRIM_ALL      = TRIM_LEADING | TRIM_TRAILING,
 };
 BASE_EXPORT TrimPositions TrimWhitespace(const string16& input,
                                          TrimPositions positions,
                                          string16* output);
 BASE_EXPORT TrimPositions TrimWhitespaceASCII(const std::string& input,
                                               TrimPositions positions,
                                               std::string* output);
 // Deprecated. This function is only for backward compatibility and calls
 // TrimWhitespaceASCII().
 BASE_EXPORT TrimPositions TrimWhitespace(const std::string& input,
                                          TrimPositions positions,
                                          std::string* output);
 // Searches  for CR or LF characters.  Removes all contiguous whitespace
 // strings that contain them.  This is useful when trying to deal with text
 // copied from terminals.
 // Returns |text|, with the following three transformations:
 // (1) Leading and trailing whitespace is trimmed.
 // (2) If |trim_sequences_with_line_breaks| is true, any other whitespace
 //     sequences containing a CR or LF are trimmed.
 // (3) All other whitespace sequences are converted to single spaces.
 BASE_EXPORT std::wstring CollapseWhitespace(
     const std::wstring& text,
     bool trim_sequences_with_line_breaks);
 BASE_EXPORT string16 CollapseWhitespace(
     const string16& text,
     bool trim_sequences_with_line_breaks);
 BASE_EXPORT std::string CollapseWhitespaceASCII(
     const std::string& text,
     bool trim_sequences_with_line_breaks);
 // Returns true if the passed string is empty or contains only white-space
 // characters.
 BASE_EXPORT bool ContainsOnlyWhitespaceASCII(const std::string& str);
 BASE_EXPORT bool ContainsOnlyWhitespace(const string16& str);
 // Returns true if |input| is empty or contains only characters found in
 // |characters|.
 BASE_EXPORT bool ContainsOnlyChars(const std::wstring& input,
                                    const std::wstring& characters);
 BASE_EXPORT bool ContainsOnlyChars(const string16& input,
                                    const string16& characters);
 BASE_EXPORT bool ContainsOnlyChars(const std::string& input,
                                    const std::string& characters);
 // Converts to 7-bit ASCII by truncating. The result must be known to be ASCII
 // beforehand.
 BASE_EXPORT std::string WideToASCII(const std::wstring& wide);
 BASE_EXPORT std::string UTF16ToASCII(const string16& utf16);
 // Converts the given wide string to the corresponding Latin1. This will fail
 // (return false) if any characters are more than 255.
 BASE_EXPORT bool WideToLatin1(const std::wstring& wide, std::string* latin1);
 // Returns true if the specified string matches the criteria. How can a wide
 // string be 8-bit or UTF8? It contains only characters that are < 256 (in the
 // first case) or characters that use only 8-bits and whose 8-bit
 // representation looks like a UTF-8 string (the second case).
 //
 // Note that IsStringUTF8 checks not only if the input is structurally
 // valid but also if it doesn't contain any non-character codepoint
 // (e.g. U+FFFE). It's done on purpose because all the existing callers want
 // to have the maximum 'discriminating' power from other encodings. If
 // there's a use case for just checking the structural validity, we have to
 // add a new function for that.
 BASE_EXPORT bool IsStringUTF8(const std::string& str);
 BASE_EXPORT bool IsStringASCII(const std::wstring& str);
 BASE_EXPORT bool IsStringASCII(const string16& str);
 // Converts the elements of the given string.  This version uses a pointer to
 // clearly differentiate it from the non-pointer variant.
 template <class str> inline void StringToLowerASCII(str* s) {
   for (typename str::iterator i = s->begin(); i != s->end(); ++i)
     *i = base::ToLowerASCII(*i);
 }
 template <class str> inline str StringToLowerASCII(const str& s) {
   // for std::string and std::wstring
   str output(s);
   StringToLowerASCII(&output);
   return output;
 }
 // Converts the elements of the given string.  This version uses a pointer to
 // clearly differentiate it from the non-pointer variant.
 template <class str> inline void StringToUpperASCII(str* s) {
   for (typename str::iterator i = s->begin(); i != s->end(); ++i)
     *i = base::ToUpperASCII(*i);
 }
 template <class str> inline str StringToUpperASCII(const str& s) {
   // for std::string and std::wstring
   str output(s);
   StringToUpperASCII(&output);
   return output;
 }
 // Compare the lower-case form of the given string against the given ASCII
 // string.  This is useful for doing checking if an input string matches some
 // token, and it is optimized to avoid intermediate string copies.  This API is
 // borrowed from the equivalent APIs in Mozilla.
 BASE_EXPORT bool LowerCaseEqualsASCII(const std::string& a, const char* b);
 BASE_EXPORT bool LowerCaseEqualsASCII(const std::wstring& a, const char* b);
 BASE_EXPORT bool LowerCaseEqualsASCII(const string16& a, const char* b);
 // Same thing, but with string iterators instead.
 BASE_EXPORT bool LowerCaseEqualsASCII(std::string::const_iterator a_begin,
                                       std::string::const_iterator a_end,
                                       const char* b);
 BASE_EXPORT bool LowerCaseEqualsASCII(std::wstring::const_iterator a_begin,
                                       std::wstring::const_iterator a_end,
                                       const char* b);
 BASE_EXPORT bool LowerCaseEqualsASCII(string16::const_iterator a_begin,
                                       string16::const_iterator a_end,
                                       const char* b);
 BASE_EXPORT bool LowerCaseEqualsASCII(const char* a_begin,
                                       const char* a_end,
                                       const char* b);
 BASE_EXPORT bool LowerCaseEqualsASCII(const wchar_t* a_begin,
                                       const wchar_t* a_end,
                                       const char* b);
 BASE_EXPORT bool LowerCaseEqualsASCII(const char16* a_begin,
                                       const char16* a_end,
                                       const char* b);
 // Performs a case-sensitive string compare. The behavior is undefined if both
 // strings are not ASCII.
 BASE_EXPORT bool EqualsASCII(const string16& a, const base::StringPiece& b);
 // Returns true if str starts with search, or false otherwise.
 BASE_EXPORT bool StartsWithASCII(const std::string& str,
                                  const std::string& search,
                                  bool case_sensitive);
 BASE_EXPORT bool StartsWith(const std::wstring& str,
                             const std::wstring& search,
                             bool case_sensitive);
 BASE_EXPORT bool StartsWith(const string16& str,
                             const string16& search,
                             bool case_sensitive);
 // Returns true if str ends with search, or false otherwise.
 BASE_EXPORT bool EndsWith(const std::string& str,
                           const std::string& search,
                           bool case_sensitive);
 BASE_EXPORT bool EndsWith(const std::wstring& str,
                           const std::wstring& search,
                           bool case_sensitive);
 BASE_EXPORT bool EndsWith(const string16& str,
                           const string16& search,
                           bool case_sensitive);
 // Determines the type of ASCII character, independent of locale (the C
 // library versions will change based on locale).
 template <typename Char>
 inline bool IsAsciiWhitespace(Char c) {
   return c == ' ' || c == '\r' || c == '\n' || c == '\t';
 }
 template <typename Char>
 inline bool IsAsciiAlpha(Char c) {
   return ((c >= 'A') && (c <= 'Z')) || ((c >= 'a') && (c <= 'z'));
 }
 template <typename Char>
 inline bool IsAsciiDigit(Char c) {
   return c >= '0' && c <= '9';
 }
 template <typename Char>
 inline bool IsHexDigit(Char c) {
   return (c >= '0' && c <= '9') ||
          (c >= 'A' && c <= 'F') ||
          (c >= 'a' && c <= 'f');
 }
 template <typename Char>
 inline Char HexDigitToInt(Char c) {
   DCHECK(IsHexDigit(c));
   if (c >= '0' && c <= '9')
     return c - '0';
   if (c >= 'A' && c <= 'F')
     return c - 'A' + 10;
   if (c >= 'a' && c <= 'f')
     return c - 'a' + 10;
   return 0;
 }
 // Returns true if it's a whitespace character.
 inline bool IsWhitespace(wchar_t c) {
   return wcschr(kWhitespaceWide, c) != NULL;
 }
 // Return a byte string in human-readable format with a unit suffix. Not
 // appropriate for use in any UI; use of FormatBytes and friends in ui/base is
 // highly recommended instead. TODO(avi): Figure out how to get callers to use
 // FormatBytes instead; remove this.
 BASE_EXPORT string16 FormatBytesUnlocalized(int64 bytes);
 // Starting at |start_offset| (usually 0), replace the first instance of
 // |find_this| with |replace_with|.
 BASE_EXPORT void ReplaceFirstSubstringAfterOffset(
     string16* str,
     string16::size_type start_offset,
     const string16& find_this,
     const string16& replace_with);
 BASE_EXPORT void ReplaceFirstSubstringAfterOffset(
     std::string* str,
     std::string::size_type start_offset,
     const std::string& find_this,
     const std::string& replace_with);
 // Starting at |start_offset| (usually 0), look through |str| and replace all
 // instances of |find_this| with |replace_with|.
 //
 // This does entire substrings; use std::replace in <algorithm> for single
 // characters, for example:
 //   std::replace(str.begin(), str.end(), 'a', 'b');
 BASE_EXPORT void ReplaceSubstringsAfterOffset(
     string16* str,
     string16::size_type start_offset,
     const string16& find_this,
     const string16& replace_with);
 BASE_EXPORT void ReplaceSubstringsAfterOffset(
     std::string* str,
     std::string::size_type start_offset,
     const std::string& find_this,
     const std::string& replace_with);
 // Reserves enough memory in |str| to accommodate |length_with_null| characters,
 // sets the size of |str| to |length_with_null - 1| characters, and returns a
 // pointer to the underlying contiguous array of characters.  This is typically
 // used when calling a function that writes results into a character array, but
 // the caller wants the data to be managed by a string-like object.  It is
 // convenient in that is can be used inline in the call, and fast in that it
 // avoids copying the results of the call from a char* into a string.
 //
 // |length_with_null| must be at least 2, since otherwise the underlying string
 // would have size 0, and trying to access &((*str)[0]) in that case can result
 // in a number of problems.
 //
 // Internally, this takes linear time because the resize() call 0-fills the
 // underlying array for potentially all
 // (|length_with_null - 1| * sizeof(string_type::value_type)) bytes.  Ideally we
 // could avoid this aspect of the resize() call, as we expect the caller to
 // immediately write over this memory, but there is no other way to set the size
 // of the string, and not doing that will mean people who access |str| rather
 // than str.c_str() will get back a string of whatever size |str| had on entry
 // to this function (probably 0).
 template <class string_type>
 inline typename string_type::value_type* WriteInto(string_type* str,
                                                    size_t length_with_null) {
   DCHECK_GT(length_with_null, 1u);
   str->reserve(length_with_null);
   str->resize(length_with_null - 1);
   return &((*str)[0]);
 }
 //-----------------------------------------------------------------------------
 // Splits a string into its fields delimited by any of the characters in
 // |delimiters|.  Each field is added to the |tokens| vector.  Returns the
 // number of tokens found.
 BASE_EXPORT size_t Tokenize(const std::wstring& str,
                             const std::wstring& delimiters,
                             std::vector<std::wstring>* tokens);
 BASE_EXPORT size_t Tokenize(const string16& str,
                             const string16& delimiters,
                             std::vector<string16>* tokens);
 BASE_EXPORT size_t Tokenize(const std::string& str,
                             const std::string& delimiters,
                             std::vector<std::string>* tokens);
 BASE_EXPORT size_t Tokenize(const base::StringPiece& str,
                             const base::StringPiece& delimiters,
                             std::vector<base::StringPiece>* tokens);
 // Does the opposite of SplitString().
 BASE_EXPORT string16 JoinString(const std::vector<string16>& parts, char16 s);
 BASE_EXPORT std::string JoinString(
     const std::vector<std::string>& parts, char s);
 // Join |parts| using |separator|.
 BASE_EXPORT std::string JoinString(
     const std::vector<std::string>& parts,
     const std::string& separator);
 BASE_EXPORT string16 JoinString(
     const std::vector<string16>& parts,
     const string16& separator);
 // Replace $1-$2-$3..$9 in the format string with |a|-|b|-|c|..|i| respectively.
 // Additionally, any number of consecutive '$' characters is replaced by that
 // number less one. Eg $$->$, $$$->$$, etc. The offsets parameter here can be
 // NULL. This only allows you to use up to nine replacements.
 BASE_EXPORT string16 ReplaceStringPlaceholders(
     const string16& format_string,
     const std::vector<string16>& subst,
     std::vector<size_t>* offsets);
 BASE_EXPORT std::string ReplaceStringPlaceholders(
     const base::StringPiece& format_string,
     const std::vector<std::string>& subst,
     std::vector<size_t>* offsets);
 // Single-string shortcut for ReplaceStringHolders. |offset| may be NULL.
 BASE_EXPORT string16 ReplaceStringPlaceholders(const string16& format_string,
                                                const string16& a,
                                                size_t* offset);
 // Returns true if the string passed in matches the pattern. The pattern
 // string can contain wildcards like * and ?
 // The backslash character (\) is an escape character for * and ?
 // We limit the patterns to having a max of 16 * or ? characters.
 // ? matches 0 or 1 character, while * matches 0 or more characters.
 BASE_EXPORT bool MatchPattern(const base::StringPiece& string,
                               const base::StringPiece& pattern);
 BASE_EXPORT bool MatchPattern(const string16& string, const string16& pattern);
 // Hack to convert any char-like type to its unsigned counterpart.
 // For example, it will convert char, signed char and unsigned char to unsigned
 // char.
 template<typename T>
 struct ToUnsigned {
   typedef T Unsigned;
 };
 template<>
 struct ToUnsigned<char> {
   typedef unsigned char Unsigned;
 };
 template<>
 struct ToUnsigned<signed char> {
   typedef unsigned char Unsigned;
 };
 template<>
 struct ToUnsigned<wchar_t> {
 #if defined(WCHAR_T_IS_UTF16)
   typedef unsigned short Unsigned;
 #elif defined(WCHAR_T_IS_UTF32)
   typedef uint32 Unsigned;
 #endif
 };
 template<>
 struct ToUnsigned<short> {
   typedef unsigned short Unsigned;
 };
 #endif  // BASE_STRINGS_STRING_UTIL_H_

The Tor Browser / annotate

security/sandbox/chromium/base/strings/string_util.h@141e0f1194b1 (annotated)

security/sandbox/chromium/base/strings/string_util.h