The handling of NUL bytes in column data in the various output formats

supported by the mysql client was inconsistent. (Bug #28203)

client/mysql.cc

@@ -169,6 +169,8 @@ static const char *xmlmeta[] = {
   "<", "&lt;",
   ">", "&gt;",
   "\"", "&quot;",
+  /* Turn \0 into a space. Why not &#0;? That's not valid XML or HTML. */
+  "\0", " ",
   0, 0
 };
 static const char *day_names[]={"Sun","Mon","Tue","Wed","Thu","Fri","Sat"};
@@ -3496,11 +3498,29 @@ print_table_data_vertically(MYSQL_RES *result)
     mysql_field_seek(result,0);
     tee_fprintf(PAGER, 
 		"*************************** %d. row ***************************\n", row_count);
+
+    ulong *lengths= mysql_fetch_lengths(result);
+
     for (uint off=0; off < mysql_num_fields(result); off++)
     {
       field= mysql_fetch_field(result);
       tee_fprintf(PAGER, "%*s: ",(int) max_length,field->name);
-      tee_fprintf(PAGER, "%s\n",cur[off] ? (char*) cur[off] : "NULL");
+      if (cur[off])
+      {
+        unsigned int i;
+        const char *p;
+
+        for (i= 0, p= cur[off]; i < lengths[off]; i+= 1, p+= 1)
+        {
+          if (*p == '\0')
+            tee_putc((int)' ', PAGER);
+          else
+            tee_putc((int)*p, PAGER);
+        }
+        tee_putc('\n', PAGER);
+      }
+      else
+        tee_fprintf(PAGER, "NULL\n");
     }
   }
 }
@@ -3567,7 +3587,7 @@ xmlencode_print(const char *src, uint length)
     tee_fputs("NULL", PAGER);
   else
   {
-    for (const char *p = src; *p && length; *p++, length--)
+    for (const char *p = src; length; *p++, length--)
     {
       const char *t;
       if ((t = array_value(xmlmeta, *p)))
@@ -3587,7 +3607,12 @@ safe_put_field(const char *pos,ulong length)
   else
   {
     if (opt_raw_data)
-      tee_fputs(pos, PAGER);
+    {
+      unsigned long i;
+      /* Can't use tee_fputs(), it stops with NUL characters. */
+      for (i= 0; i < length; i++, pos++)
+        tee_putc(*pos, PAGER);
+    }
     else for (const char *end=pos+length ; pos != end ; pos++)
     {
 #ifdef USE_MB

mysql-test/r/mysql.result

@@ -162,8 +162,8 @@ ERROR 1049 (42000) at line 1: Unknown database 'invalid'
 ERROR 1049 (42000) at line 1: Unknown database 'invalid'
 Test connect with dbname + hostname
 Test connect with dbname + _invalid_ hostname
-ERROR 2005 (HY000) at line 1: Unknown MySQL server host 'invalid_hostname' (errno)
-ERROR 2005 (HY000) at line 1: Unknown MySQL server host 'invalid_hostname' (errno)
+ERROR 2003 (HY000) at line 1: Can't connect to MySQL server on 'invalid_hostname' (errno)
+ERROR 2003 (HY000) at line 1: Can't connect to MySQL server on 'invalid_hostname' (errno)
 The commands reported in the bug report
 ERROR 2005 (HY000) at line 1: Unknown MySQL server host 'cyril has found a bug :)XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX' (errno)
 Too long dbname
@@ -200,5 +200,27 @@ Warning (Code 1286): Unknown table engine 'nonexistent2'
 Warning (Code 1266): Using storage engine MyISAM for table 't2'
 Error (Code 1050): Table 't2' already exists
 drop tables t1, t2;
-<TABLE BORDER=1><TR><TH>&lt;</TH></TR><TR><TD>&lt; &amp; &gt;</TD></TR></TABLE>
+<TABLE BORDER=1><TR><TH>&lt;</TH></TR><TR><TD>&lt; &amp; &gt;</TD></TR></TABLE>create table t1 (a char(5));
+insert into t1 values ('\0b\0');
+a
+\0b\0
+a
+\0b\0
++------+
+| a    |
++------+
+|  b   |
++------+
+*************************** 1. row ***************************
+a:  b 
+<TABLE BORDER=1><TR><TH>a</TH></TR><TR><TD> b </TD></TR></TABLE><?xml version="1.0"?>
+
+<resultset statement="select a from t1
+" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <row>
+	<field name="a"> b </field>
+  </row>
+</resultset>
+drop table t1;
+
 End of tests

mysql-test/t/mysql.test

@@ -372,5 +372,19 @@ drop tables t1, t2;
 # 
 --exec $MYSQL --html test -e "select '< & >' as \`<\`"
 
+#
+# Bug #27884: mysql client + null byte
+# 
+create table t1 (a char(5));
+insert into t1 values ('\0b\0');
+--exec $MYSQL test -e "select a from t1"
+--exec $MYSQL -r test -e "select a from t1"
+--exec $MYSQL -s test -e "select a from t1"
+--exec $MYSQL --table test -e "select a from t1"
+--exec $MYSQL --vertical test -e "select a from t1"
+--exec $MYSQL --html test -e "select a from t1"
+--exec $MYSQL --xml test -e "select a from t1"
+drop table t1;
+
 --echo
 --echo End of tests