Handle octal escapes in /proc/self/mountinfo

2 files changed, 21 insertions, 0 deletions

diff --git a/src/libutil/util.cc b/src/libutil/util.cc
index 7f95d3981..afb0dc0b2 100644
--- a/src/libutil/util.cc
+++ b/src/libutil/util.cc
@@ -1101,6 +1101,21 @@ bool endOfList(std::istream & str)
 }
 
 
+string decodeOctalEscaped(const string & s)
+{
+    string r;
+    for (string::const_iterator i = s.begin(); i != s.end(); ) {
+        if (*i != '\\') { r += *i++; continue; }
+        unsigned char c = 0;
+        ++i;
+        while (i != s.end() && *i >= '0' && *i < '8')
+            c = c * 8 + (*i++ - '0');
+        r += c;
+    }
+    return r;
+}
+
+
 void ignoreException()
 {
     try {
diff --git a/src/libutil/util.hh b/src/libutil/util.hh
index 408d99a96..d3861f730 100644
--- a/src/libutil/util.hh
+++ b/src/libutil/util.hh
@@ -332,6 +332,12 @@ string parseString(std::istream & str);
 bool endOfList(std::istream & str);
 
 
+/* Escape a string that contains octal-encoded escape codes such as
+   used in /etc/fstab and /proc/mounts (e.g. "foo\040bar" decodes to
+   "foo bar"). */
+string decodeOctalEscaped(const string & s);
+
+
 /* Exception handling in destructors: print an error message, then
    ignore the exception. */
 void ignoreException();