Support multi-line C++11 strings in Ebrowse

* lib-src/ebrowse.c (yylex): Support C++11 multi-line strings.
(bug#58847)

1 files changed, 62 insertions, 1 deletions

diff --git a/lib-src/ebrowse.c b/lib-src/ebrowse.c
index 641570da02e..d3af926b634 100644
--- a/lib-src/ebrowse.c
+++ b/lib-src/ebrowse.c
@@ -1574,6 +1574,67 @@ yylex (void)
 
         end_string:
           return end_char == '\'' ? CCHAR : CSTRING;
+        case 'R':
+          if (GET (c) == '"')
+            {
+              /* C++11 rstrings.  */
+
+#define RSTRING_EOF_CHECK                                               \
+              do {                                                      \
+                if (c == '\0')                                          \
+                  {                                                     \
+                    yyerror ("unterminated c++11 rstring", NULL);       \
+                    UNGET ();                                           \
+                    return CSTRING;                                     \
+                  }                                                     \
+              } while (0)
+
+            char *rstring_prefix_start = in;
+
+            while (GET (c) != '(')
+              {
+                RSTRING_EOF_CHECK;
+                if (c == '"')
+                  {
+                    yyerror ("malformed c++11 rstring", NULL);
+                    return CSTRING;
+                  }
+              }
+            char *rstring_prefix_end = in - 1;
+            while (TRUE)
+              {
+                switch (GET (c))
+                  {
+                  default:
+                    RSTRING_EOF_CHECK;
+                    break;
+                  case '\n':
+                    INCREMENT_LINENO;
+                    break;
+                  case ')':
+                    {
+                      char *in_saved = in;
+                      char *prefix = rstring_prefix_start;
+                      while (prefix != rstring_prefix_end && GET (c) == *prefix)
+                        {
+                          RSTRING_EOF_CHECK;
+                          prefix++;
+                        }
+                      if (prefix == rstring_prefix_end)
+                        {
+                          if (GET (c) == '"')
+                            return CSTRING;
+                          RSTRING_EOF_CHECK;
+                        }
+                      in = in_saved;
+                    }
+                  }
+              }
+            }
+
+          UNGET ();
+          /* Fall through to identifiers and keywords.  */
+          FALLTHROUGH;
 
         case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': case 'g':
         case 'h': case 'i': case 'j': case 'k': case 'l': case 'm': case 'n':
@@ -1581,7 +1642,7 @@ yylex (void)
         case 'v': case 'w': case 'x': case 'y': case 'z':
         case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': case 'G':
         case 'H': case 'I': case 'J': case 'K': case 'L': case 'M': case 'N':
-        case 'O': case 'P': case 'Q': case 'R': case 'S': case 'T': case 'U':
+        case 'O': case 'P': case 'Q': case 'S': case 'T': case 'U':
         case 'V': case 'W': case 'X': case 'Y': case 'Z': case '_':
           {
             /* Identifier and keywords.  */