LLVM  4.0.0
StringExtras.cpp
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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.
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.
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.
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 }
void push_back(const T &Elt)
Definition: SmallVector.h:211
size_t i
LLVM_NODISCARD bool equals_lower(StringRef RHS) const
equals_lower - Check for string equality, ignoring case.
Definition: StringRef.h:173
std::pair< StringRef, StringRef > getToken(StringRef Source, StringRef Delimiters=" \t\n\v\f\r")
getToken - This function extracts one token from source, ignoring any leading characters that appear ...
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE StringRef slice(size_t Start, size_t End) const
Return a reference to the substring from [Start, End).
Definition: StringRef.h:699
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE size_t size() const
size - Get the string size.
Definition: StringRef.h:135
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE StringRef substr(size_t Start, size_t N=npos) const
Return a reference to the substring from [Start, Start + N).
Definition: StringRef.h:587
static const unsigned End
LLVM_NODISCARD size_t find_first_not_of(char C, size_t From=0) const
Find the first character in the string that is not C or npos if not found.
Definition: StringRef.cpp:264
void SplitString(StringRef Source, SmallVectorImpl< StringRef > &OutFragments, StringRef Delimiters=" \t\n\v\f\r")
SplitString - Split up the specified string according to the specified delimiters, appending the result fragments to the output list.
static const size_t npos
Definition: StringRef.h:51
size_t size_type
Definition: StringRef.h:52
#define N
StringRef::size_type StrInStrNoCase(StringRef s1, StringRef s2)
StrInStrNoCase - Portable version of strcasestr.
LLVM_NODISCARD size_t find_first_of(char C, size_t From=0) const
Find the first character in the string that is C, or npos if not found.
Definition: StringRef.h:392
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:47