• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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/SmallVector.h"
15 #include "llvm/ADT/StringExtras.h"
16 using namespace llvm;
17 
18 /// StrInStrNoCase - Portable version of strcasestr.  Locates the first
19 /// occurrence of string 's1' in string 's2', ignoring case.  Returns
20 /// the offset of s2 in s1 or npos if s2 cannot be found.
StrInStrNoCase(StringRef s1,StringRef s2)21 StringRef::size_type llvm::StrInStrNoCase(StringRef s1, StringRef s2) {
22   size_t N = s2.size(), M = s1.size();
23   if (N > M)
24     return StringRef::npos;
25   for (size_t i = 0, e = M - N + 1; i != e; ++i)
26     if (s1.substr(i, N).equals_lower(s2))
27       return i;
28   return StringRef::npos;
29 }
30 
31 /// getToken - This function extracts one token from source, ignoring any
32 /// leading characters that appear in the Delimiters string, and ending the
33 /// token at any of the characters that appear in the Delimiters string.  If
34 /// there are no tokens in the source string, an empty string is returned.
35 /// The function returns a pair containing the extracted token and the
36 /// remaining tail string.
getToken(StringRef Source,StringRef Delimiters)37 std::pair<StringRef, StringRef> llvm::getToken(StringRef Source,
38                                                StringRef Delimiters) {
39   // Figure out where the token starts.
40   StringRef::size_type Start = Source.find_first_not_of(Delimiters);
41 
42   // Find the next occurrence of the delimiter.
43   StringRef::size_type End = Source.find_first_of(Delimiters, Start);
44 
45   return std::make_pair(Source.slice(Start, End), Source.substr(End));
46 }
47 
48 /// SplitString - Split up the specified string according to the specified
49 /// delimiters, appending the result fragments to the output list.
SplitString(StringRef Source,SmallVectorImpl<StringRef> & OutFragments,StringRef Delimiters)50 void llvm::SplitString(StringRef Source,
51                        SmallVectorImpl<StringRef> &OutFragments,
52                        StringRef Delimiters) {
53   std::pair<StringRef, StringRef> S = getToken(Source, Delimiters);
54   while (!S.first.empty()) {
55     OutFragments.push_back(S.first);
56     S = getToken(S.second, Delimiters);
57   }
58 }
59