[llvm-commits] CVS: llvm/lib/Support/StringExtras.cpp
Chris Lattner
lattner at cs.uiuc.edu
Fri Jul 14 15:54:51 PDT 2006
Changes in directory llvm/lib/Support:
StringExtras.cpp updated: 1.3 -> 1.4
---
Log message:
Add two helpers for escaping and unescaping strings.
---
Diffs of the changes: (+50 -0)
StringExtras.cpp | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 50 insertions(+)
Index: llvm/lib/Support/StringExtras.cpp
diff -u llvm/lib/Support/StringExtras.cpp:1.3 llvm/lib/Support/StringExtras.cpp:1.4
--- llvm/lib/Support/StringExtras.cpp:1.3 Thu Apr 21 17:52:05 2005
+++ llvm/lib/Support/StringExtras.cpp Fri Jul 14 17:54:39 2006
@@ -41,3 +41,53 @@
return Result;
}
+
+
+/// UnescapeString - Modify the argument string, turning two character sequences
+/// 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).
+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;
+ }
+ // 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] == '\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));
+ }
+ }
+}
More information about the llvm-commits
mailing list