lib/Support/StringExtras.cpp

   1 //===-- StringExtras.cpp - Implement the StringExtras header --------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file implements the StringExtras.h header
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/ADT/StringExtras.h"
  15 #include "llvm/ADT/SmallVector.h"
  16 #include "llvm/Support/raw_ostream.h"
  17 using namespace llvm;
  18
  19 /// StrInStrNoCase - Portable version of strcasestr.  Locates the first
  20 /// occurrence of string 's1' in string 's2', ignoring case.  Returns
  21 /// the offset of s2 in s1 or npos if s2 cannot be found.
  22 StringRef::size_type llvm::StrInStrNoCase(StringRef s1, StringRef s2) {
  23   size_t N = s2.size(), M = s1.size();
  24   if (N > M)
  25     return StringRef::npos;
  26   for (size_t i = 0, e = M - N + 1; i != e; ++i)
  27     if (s1.substr(i, N).equals_lower(s2))
  28       return i;
  29   return StringRef::npos;
  30 }
  31
  32 /// getToken - This function extracts one token from source, ignoring any
  33 /// leading characters that appear in the Delimiters string, and ending the
  34 /// token at any of the characters that appear in the Delimiters string.  If
  35 /// there are no tokens in the source string, an empty string is returned.
  36 /// The function returns a pair containing the extracted token and the
  37 /// remaining tail string.
  38 std::pair<StringRef, StringRef> llvm::getToken(StringRef Source,
  39                                                StringRef Delimiters) {
  40   // Figure out where the token starts.
  41   StringRef::size_type Start = Source.find_first_not_of(Delimiters);
  42
  43   // Find the next occurrence of the delimiter.
  44   StringRef::size_type End = Source.find_first_of(Delimiters, Start);
  45
  46   return std::make_pair(Source.slice(Start, End), Source.substr(End));
  47 }
  48
  49 /// SplitString - Split up the specified string according to the specified
  50 /// delimiters, appending the result fragments to the output list.
  51 void llvm::SplitString(StringRef Source,
  52                        SmallVectorImpl<StringRef> &OutFragments,
  53                        StringRef Delimiters) {
  54   std::pair<StringRef, StringRef> S = getToken(Source, Delimiters);
  55   while (!S.first.empty()) {
  56     OutFragments.push_back(S.first);
  57     S = getToken(S.second, Delimiters);
  58   }
  59 }
  60
  61 void llvm::printEscapedString(StringRef Name, raw_ostream &Out) {
  62   for (unsigned i = 0, e = Name.size(); i != e; ++i) {
  63     unsigned char C = Name[i];
  64     if (isPrint(C) && C != '\\' && C != '"')
  65       Out << C;
  66     else
  67       Out << '\\' << hexdigit(C >> 4) << hexdigit(C & 0x0F);
  68   }
  69 }
  70
  71 void llvm::printHTMLEscaped(StringRef String, raw_ostream &Out) {
  72   for (char C : String) {
  73     if (C == '&')
  74       Out << "&amp;";
  75     else if (C == '<')
  76       Out << "&lt;";
  77     else if (C == '>')
  78       Out << "&gt;";
  79     else if (C == '\"')
  80       Out << "&quot;";
  81     else if (C == '\'')
  82       Out << "&apos;";
  83     else
  84       Out << C;
  85   }
  86 }
  87
  88 void llvm::printLowerCase(StringRef String, raw_ostream &Out) {
  89   for (const char C : String)
  90     Out << toLower(C);
  91 }