bin: better shell quoting for ltlcross and ltldo

* src/bin/common_trans.cc: Use double-quotes when single-quotes
cannot do.
* src/tests/ltlcross3.test: Add a test case.
* NEWS: Mention it.

NEWS

@@ -36,6 +36,8 @@ New in spot 1.99.1a (not yet released)
     - scc_filter() would incorrectly remove Fin marks from
       rejecting SCCs.
     - the libspotltsmin library is installed
+    - ltlcross and ltldo did not properly quote atomic propositions
+      and temporary file names containing a single-quote
 
 
 New in spot 1.99.1 (2015-06-23)

src/bin/common_trans.cc

@@ -146,12 +146,39 @@ translator_spec::~translator_spec()
 
 std::vector<translator_spec> translators;
 
+static void
+quote_shell_string(std::ostream& os, const char* str)
+{
+  // Single quotes are best, unless the string to quote contains one.
+  if (!strchr(str, '\''))
+    {
+      os << '\'' << str << '\'';
+    }
+  else
+    {
+      // In double quotes we have to escape $ ` " or \.
+      os << '"';
+      while (*str)
+	switch (*str)
+	  {
+	  case '$':
+	  case '`':
+	  case '"':
+	  case '\\':
+	    os << '\\';
+	    // fall through
+	  default:
+	    os << *str++;
+	    break;
+	  }
+      os << '"';
+    }
+}
+
 void
-quoted_string::print(std::ostream& os, const char* pos) const
+quoted_string::print(std::ostream& os, const char*) const
 {
-  os << '\'';
-  this->spot::printable_value<std::string>::print(os, pos);
-  os << '\'';
+  quote_shell_string(os, val().c_str());
 }
 
 printable_result_filename::printable_result_filename()
@@ -204,7 +231,7 @@ printable_result_filename::print(std::ostream& os, const char* pos) const
       const_cast<printable_result_filename*>(this)->val_
 	= spot::create_tmpfile(prefix);
     }
-  os << '\'' << val_ << '\'';
+  quote_shell_string(os, val()->name());
 }
 
 

src/tests/ltlcross3.test

@@ -33,6 +33,14 @@ check_csv()
 
 ltl2tgba=../../bin/ltl2tgba
 
+# Make sure ltlcross quotes formulas correctly
+cat >formula <<\EOF
+G"a'-'>'b"
+EOF
+run 0 ../../bin/ltlcross -F formula --csv=out.csv \
+                         "$ltl2tgba -s %f >%N" \
+                         "$ltl2tgba --lenient -s %s >%N"
+
 run 2 ../../bin/ltlcross "$ltl2tgba -s %f >%N" 'foo bar' 2>stderr -f a
 grep 'ltlcross.*no input.*in.*foo bar' stderr