1 files changed, 57 insertions, 4 deletions
diff --git a/sql/sql_string.cc b/sql/sql_string.cc
index 62473e082c3..b12f0332035 100644
--- a/sql/sql_string.cc
+++ b/sql/sql_string.cc
@@ -130,6 +130,61 @@ bool String::set_int(longlong num, bool unsigned_flag, CHARSET_INFO *cs)
   return FALSE;
 }
 
+
+// Convert a number into its HEX representation
+bool String::set_hex(ulonglong num)
+{
+  char *n_end;
+  if (alloc(65) || !(n_end= longlong2str(num, Ptr, 16)))
+    return true;
+  length((uint32) (n_end - Ptr));
+  set_charset(&my_charset_latin1);
+  return false;
+}
+
+
+/**
+  Append a hex representation of the byte "value" into "to".
+  Note:
+    "to" is incremented for the caller by two bytes. It's passed by reference!
+    So it resembles a macros, hence capital letters in the name.
+*/
+static inline void APPEND_HEX(char *&to, uchar value)
+{
+  *to++= _dig_vec_upper[((uchar) value) >> 4];
+  *to++= _dig_vec_upper[((uchar) value) & 0x0F];
+}
+
+
+void String::qs_append_hex(const char *str, uint32 len)
+{
+  const char *str_end= str + len;
+  for (char *to= Ptr + str_length ; str < str_end; str++)
+    APPEND_HEX(to, (uchar) *str);
+  str_length+= len * 2;
+}
+
+
+// Convert a string to its HEX representation
+bool String::set_hex(const char *str, uint32 len)
+{
+  /*
+    Safety: cut the source string if "len" is too large.
+    Note, alloc() can allocate some more space than requested, due to:
+    - ALIGN_SIZE
+    - one extra byte for a null terminator
+    So cut the source string to 0x7FFFFFF0 rather than 0x7FFFFFFE.
+  */
+  set_if_smaller(len, 0x7FFFFFF0);
+  if (alloc(len * 2))
+    return true;
+  length(0);
+  qs_append_hex(str, len);
+  set_charset(&my_charset_latin1);
+  return false;
+}
+
+
 bool String::set_real(double num,uint decimals, CHARSET_INFO *cs)
 {
   char buff[FLOATING_POINT_BUFFER];
@@ -960,8 +1015,7 @@ my_copy_with_hex_escaping(CHARSET_INFO *cs,
         break; /* purecov: inspected */
       *dst++= '\\';
       *dst++= 'x';
-      *dst++= _dig_vec_upper[((unsigned char) *src) >> 4];
-      *dst++= _dig_vec_upper[((unsigned char) *src) & 15];
+      APPEND_HEX(dst, (uchar) *src);
       src++;
       dstlen-= 4;
     }
@@ -1146,8 +1200,7 @@ uint convert_to_printable(char *to, size_t to_len,
         break;
       *t++= '\\';
       *t++= 'x';
-      *t++= _dig_vec_upper[((unsigned char) *f) >> 4];
-      *t++= _dig_vec_upper[((unsigned char) *f) & 0x0F];
+      APPEND_HEX(t, *f);
     }
     if (t_end - t >= 3) // '...'
       dots= t;