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-rw-r--r--lib/Support/StringExtras.cpp114
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diff --git a/lib/Support/StringExtras.cpp b/lib/Support/StringExtras.cpp
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+//===-- StringExtras.cpp - Implement the StringExtras header --------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the StringExtras.h header
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/StringExtras.h"
+#include <cstring>
+using namespace llvm;
+
+/// getToken - This function extracts one token from source, ignoring any
+/// leading characters that appear in the Delimiters string, and ending the
+/// token at any of the characters that appear in the Delimiters string. If
+/// there are no tokens in the source string, an empty string is returned.
+/// The Source source string is updated in place to remove the returned string
+/// and any delimiter prefix from it.
+std::string llvm::getToken(std::string &Source, const char *Delimiters) {
+ size_t NumDelimiters = std::strlen(Delimiters);
+
+ // Figure out where the token starts.
+ std::string::size_type Start =
+ Source.find_first_not_of(Delimiters, 0, NumDelimiters);
+ if (Start == std::string::npos) Start = Source.size();
+
+ // Find the next occurance of the delimiter.
+ std::string::size_type End =
+ Source.find_first_of(Delimiters, Start, NumDelimiters);
+ if (End == std::string::npos) End = Source.size();
+
+ // Create the return token.
+ std::string Result = std::string(Source.begin()+Start, Source.begin()+End);
+
+ // Erase the token that we read in.
+ Source.erase(Source.begin(), Source.begin()+End);
+
+ return Result;
+}
+
+/// SplitString - Split up the specified string according to the specified
+/// delimiters, appending the result fragments to the output list.
+void llvm::SplitString(const std::string &Source,
+ std::vector<std::string> &OutFragments,
+ const char *Delimiters) {
+ std::string S = Source;
+
+ std::string S2 = getToken(S, Delimiters);
+ while (!S2.empty()) {
+ OutFragments.push_back(S2);
+ S2 = getToken(S, Delimiters);
+ }
+}
+
+
+
+/// UnescapeString - Modify the argument string, turning two character sequences
+/// @verbatim
+/// like '\\' 'n' into '\n'. This handles: \e \a \b \f \n \r \t \v \' \ and
+/// \num (where num is a 1-3 byte octal value).
+/// @endverbatim
+void llvm::UnescapeString(std::string &Str) {
+ for (unsigned i = 0; i != Str.size(); ++i) {
+ if (Str[i] == '\\' && i != Str.size()-1) {
+ switch (Str[i+1]) {
+ default: continue; // Don't execute the code after the switch.
+ case 'a': Str[i] = '\a'; break;
+ case 'b': Str[i] = '\b'; break;
+ case 'e': Str[i] = 27; break;
+ case 'f': Str[i] = '\f'; break;
+ case 'n': Str[i] = '\n'; break;
+ case 'r': Str[i] = '\r'; break;
+ case 't': Str[i] = '\t'; break;
+ case 'v': Str[i] = '\v'; break;
+ case '"': Str[i] = '\"'; break;
+ case '\'': Str[i] = '\''; break;
+ case '\\': Str[i] = '\\'; break;
+ }
+ // Nuke the second character.
+ Str.erase(Str.begin()+i+1);
+ }
+ }
+}
+
+/// EscapeString - Modify the argument string, turning '\\' and anything that
+/// doesn't satisfy std::isprint into an escape sequence.
+void llvm::EscapeString(std::string &Str) {
+ for (unsigned i = 0; i != Str.size(); ++i) {
+ if (Str[i] == '\\') {
+ ++i;
+ Str.insert(Str.begin()+i, '\\');
+ } else if (Str[i] == '\t') {
+ Str[i++] = '\\';
+ Str.insert(Str.begin()+i, 't');
+ } else if (Str[i] == '"') {
+ Str.insert(Str.begin()+i++, '\\');
+ } else if (Str[i] == '\n') {
+ Str[i++] = '\\';
+ Str.insert(Str.begin()+i, 'n');
+ } else if (!std::isprint(Str[i])) {
+ // Always expand to a 3-digit octal escape.
+ unsigned Char = Str[i];
+ Str[i++] = '\\';
+ Str.insert(Str.begin()+i++, '0'+((Char/64) & 7));
+ Str.insert(Str.begin()+i++, '0'+((Char/8) & 7));
+ Str.insert(Str.begin()+i , '0'+( Char & 7));
+ }
+ }
+}
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