Refactor \x processing to single function

There are three places that process \x.  These can and did get out of
sync.  This moves all three to use a common static inline function so
that they all do the same thing on the same inputs, and their behaviors
will not drift apart again.

This commit should not change current behavior.  A previous commit
was designed to bring all three to identical behavior.

1 files changed, 67 insertions, 0 deletions

diff --git a/dquote_static.c b/dquote_static.c
index 02e39cfd77..4f839ee542 100644
--- a/dquote_static.c
+++ b/dquote_static.c
@@ -164,6 +164,73 @@ S_grok_bslash_o(pTHX_ const char *s,
     return TRUE;
 }
 
+PERL_STATIC_INLINE bool
+S_grok_bslash_x(pTHX_ const char *s,
+			 UV *uv,
+			 STRLEN *len,
+			 const char** error_msg,
+			 const bool output_warning)
+{
+
+/*  Documentation to be supplied when interface nailed down finally
+ *  This returns FALSE if there is an error which the caller need not recover
+ *  from; , otherwise TRUE.  In either case the caller should look at *len
+ *  On input:
+ *	s   points to a string that begins with 'x', and the previous character
+ *	    was a backslash.
+ *	uv  points to a UV that will hold the output value, valid only if the
+ *	    return from the function is TRUE
+ *	len on success will point to the next character in the string past the
+ *		       end of this construct.
+ *	    on failure, it will point to the failure
+ *      error_msg is a pointer that will be set to an internal buffer giving an
+ *	    error message upon failure (the return is FALSE).  Untouched if
+ *	    function succeeds
+ *	output_warning says whether to output any warning messages, or suppress
+ *	    them
+ */
+    const char* e;
+    STRLEN numbers_len;
+    I32 flags = PERL_SCAN_ALLOW_UNDERSCORES
+		| PERL_SCAN_DISALLOW_PREFIX;
+
+    PERL_ARGS_ASSERT_GROK_BSLASH_X;
+
+
+    assert(*s == 'x');
+    s++;
+
+    if (*s != '{') {
+	I32 flags = PERL_SCAN_DISALLOW_PREFIX;
+	*len = 2;
+	*uv = grok_hex(s, len, &flags, NULL);
+	(*len)++;
+	return TRUE;
+    }
+
+    e = strchr(s, '}');
+    if (!e) {
+	*len = 2;	/* Move past the 'x{' */
+        /* XXX The corresponding message above for \o is just '\\o{'; other
+         * messages for other constructs include the '}', so are inconsistent.
+         */
+	*error_msg = "Missing right brace on \\x{}";
+	return FALSE;
+    }
+
+    /* Return past the '}' no matter what is inside the braces */
+    *len = e - s + 2;	/* 2 = 1 for the 'x' + 1 for the '}' */
+
+    s++;    /* Point to first digit */
+
+    numbers_len = e - s;
+    *uv = grok_hex(s, &numbers_len, &flags, NULL);
+    /* Note that if has non-hex, will ignore everything starting with that up
+     * to the '}' */
+
+    return TRUE;
+}
+
 /*
  * Local variables:
  * c-indentation-style: bsd