Merge pull request #223 from fe-dagostino/fix_escaping

add \a \b \v for correct escaping

doc/libconfig.texi

@@ -563,7 +563,7 @@ Boolean values may have one of the following values: @samp{true},
 String values consist of arbitrary text delimited by double
 quotes. Literal double quotes can be escaped by preceding them with a
 backslash: @samp{\"}. The escape sequences @samp{\\}, @samp{\f},
-@samp{\n}, @samp{\r}, and @samp{\t} are also recognized, and have the
+@samp{\n}, @samp{\r}, @samp{\a}, @samp{\b}, @samp{\v} and @samp{\t} are also recognized, and have the
 usual meaning.
 
 In addition, the @samp{\x} escape sequence is supported; this sequence

lib/scanner.l

@@ -81,9 +81,12 @@ include_open ^[ \t]*@include[ \t]+\"
 
 \"                { BEGIN STRING; }
 <STRING>[^\"\\]+  { libconfig_scanctx_append_string(yyextra, yytext); }
+<STRING>\\a       { libconfig_scanctx_append_char(yyextra, '\a'); }
+<STRING>\\b       { libconfig_scanctx_append_char(yyextra, '\b'); }
 <STRING>\\n       { libconfig_scanctx_append_char(yyextra, '\n'); }
 <STRING>\\r       { libconfig_scanctx_append_char(yyextra, '\r'); }
 <STRING>\\t       { libconfig_scanctx_append_char(yyextra, '\t'); }
+<STRING>\\v       { libconfig_scanctx_append_char(yyextra, '\v'); }
 <STRING>\\f       { libconfig_scanctx_append_char(yyextra, '\f'); }
 <STRING>\\\\      { libconfig_scanctx_append_char(yyextra, '\\'); }
 <STRING>\\\"      { libconfig_scanctx_append_char(yyextra, '\"'); }
@@ -125,7 +128,7 @@ include_open ^[ \t]*@include[ \t]+\"
   BEGIN INITIAL;
 }
 
-\n|\r|\f          { /* ignore */ }
+\n|\r|\f|\a|\b|\v { /* ignore */ }
 [ \t]+            { /* ignore */ }
 
 \=|\:             { return(TOK_EQUALS); }