Move string files in base/ to the string subdirectory.

base/string_util.h

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 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_STRING_UTIL_H_
-#define BASE_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/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/string_util_win.h"
-#elif defined(OS_POSIX)
-#include "base/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 base::StringPiece& 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_STRING_UTIL_H_
+// This file has moved, please use the new location.
+// TODO(avi) remove this file when all users have been updated.
+#include "base/strings/string_util.h"