Ada: handle char literal

The test case is taken from #2914 submitted by @koenmeersman.

Signed-off-by: Masatake YAMATO <[email protected]>

Author: masatake

Units/parser-ada.r/ada-char-literal.d/expected.tags-e

@@ -0,0 +1,5 @@
+
+input.adb,158
+package body System.Val_Util isSystem.Val_Util/b
4,69
+  procedure Bad_Value (S : String) isBad_Value/p
6,102
+  procedure Not_Tagged  isNot_Tagged/p
11,236

Units/parser-ada.r/ada-char-literal.d/input.adb

@@ -0,0 +1,15 @@
+--- file: s-valuti.adb
+with System.Case_Util; use System.Case_Util;
+
+package body System.Val_Util is
+
+  procedure Bad_Value (S : String) is
+  begin
+    raise Constraint_Error with "bad input for 'Value: """ & S & '"';
+  end Bad_Value;
+
+  procedure Not_Tagged  is
+  begin
+    null;
+  end Not_Tagged;
+end System.Val_Util;

parsers/ada.c

@@ -642,6 +642,10 @@ static void movePos(int amount)
    strncasecmp(&(buf)[(pos)], "--", strlen("--")) == 0)
 #define isAdaStringLiteral(buf, pos, len) \
   (((pos) < (len)) && ((buf)[(pos)] == '"'))
+#define isAdaCharLiteral(buf, pos, len) \
+  (((pos) < (len - 2)) && ((buf)[(pos)] == '\'') \
+   && ((buf)[(pos + 2)] == '\''))
+
 
 static bool cmp(const char *buf, int len, const char *match)
 {
@@ -789,8 +793,8 @@ static void skipComments(void)
   }
 }
 
-/* Return true if skipped over a string literal.
- * Return false if no string literal is found. */
+/* Return true if skipped over a string literal (or char literal).
+ * Return false if no string literal (nor char literal) is found. */
 static bool skipStringLiteral(void)
 {
   if (exception != EXCEPTION_EOF && isAdaStringLiteral(line, pos, lineLen))
@@ -802,6 +806,9 @@ static bool skipStringLiteral(void)
     /* Go to the next char of " */
     movePos(1);
 
+    return true;
+  } else if (exception != EXCEPTION_EOF && isAdaCharLiteral(line, pos, lineLen)) {
+    movePos(3);
     return true;
   }
   return false;