1 /* Copyright (c) 2000, 2018 Oracle and/or its affiliates. All rights reserved.
2 
3    This program is free software; you can redistribute it and/or modify
4    it under the terms of the GNU General Public License, version 2.0,
5    as published by the Free Software Foundation.
6 
7    This program is also distributed with certain software (including
8    but not limited to OpenSSL) that is licensed under separate terms,
9    as designated in a particular file or component or in included license
10    documentation.  The authors of MySQL hereby grant you an additional
11    permission to link the program and your derivative works with the
12    separately licensed software that they have included with MySQL.
13 
14    Without limiting anything contained in the foregoing, this file,
15    which is part of C Driver for MySQL (Connector/C), is also subject to the
16    Universal FOSS Exception, version 1.0, a copy of which can be found at
17    http://oss.oracle.com/licenses/universal-foss-exception.
18 
19    This program is distributed in the hope that it will be useful,
20    but WITHOUT ANY WARRANTY; without even the implied warranty of
21    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22    GNU General Public License, version 2.0, for more details.
23 
24    You should have received a copy of the GNU General Public License
25    along with this program; if not, write to the Free Software
26    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA */
27 
28 #include <my_global.h>
29 #include <mysql_com.h>
30 #include <mysql.h>
31 
32 /* Get the length of next field. Change parameter to point at fieldstart */
net_field_length(uchar ** packet)33 ulong STDCALL net_field_length(uchar **packet)
34 {
35   reg1 uchar *pos= (uchar *)*packet;
36   if (*pos < 251)
37   {
38     (*packet)++;
39     return (ulong) *pos;
40   }
41   if (*pos == 251)
42   {
43     (*packet)++;
44     return NULL_LENGTH;
45   }
46   if (*pos == 252)
47   {
48     (*packet)+=3;
49     return (ulong) uint2korr(pos+1);
50   }
51   if (*pos == 253)
52   {
53     (*packet)+=4;
54     return (ulong) uint3korr(pos+1);
55   }
56   (*packet)+=9;					/* Must be 254 when here */
57   return (ulong) uint4korr(pos+1);
58 }
59 
60 /* The same as above but with max length check */
net_field_length_checked(uchar ** packet,ulong max_length)61 ulong STDCALL net_field_length_checked(uchar **packet, ulong max_length)
62 {
63   ulong len;
64   uchar *pos= (uchar *)*packet;
65 
66   if (*pos < 251)
67   {
68     (*packet)++;
69     len= (ulong) *pos;
70     return (len > max_length) ? max_length : len;
71   }
72   if (*pos == 251)
73   {
74     (*packet)++;
75     return NULL_LENGTH;
76   }
77   if (*pos == 252)
78   {
79     (*packet)+=3;
80     len= (ulong) uint2korr(pos+1);
81     return (len > max_length) ? max_length : len;
82   }
83   if (*pos == 253)
84   {
85     (*packet)+=4;
86     len= (ulong) uint3korr(pos+1);
87     return (len > max_length) ? max_length : len;
88   }
89   (*packet)+=9;                                 /* Must be 254 when here */
90   len= (ulong) uint4korr(pos+1);
91   return (len > max_length) ? max_length : len;
92 }
93 
94 /* The same as above but returns longlong */
net_field_length_ll(uchar ** packet)95 my_ulonglong net_field_length_ll(uchar **packet)
96 {
97   reg1 uchar *pos= *packet;
98   if (*pos < 251)
99   {
100     (*packet)++;
101     return (my_ulonglong) *pos;
102   }
103   if (*pos == 251)
104   {
105     (*packet)++;
106     return (my_ulonglong) NULL_LENGTH;
107   }
108   if (*pos == 252)
109   {
110     (*packet)+=3;
111     return (my_ulonglong) uint2korr(pos+1);
112   }
113   if (*pos == 253)
114   {
115     (*packet)+=4;
116     return (my_ulonglong) uint3korr(pos+1);
117   }
118   (*packet)+=9;					/* Must be 254 when here */
119 #ifdef NO_CLIENT_LONGLONG
120   return (my_ulonglong) uint4korr(pos+1);
121 #else
122   return (my_ulonglong) uint8korr(pos+1);
123 #endif
124 }
125 
126 /*
127   Store an integer with simple packing into a output package
128 
129   SYNOPSIS
130     net_store_length()
131     pkg			Store the packed integer here
132     length		integers to store
133 
134   NOTES
135     This is mostly used to store lengths of strings.
136     We have to cast the result for the LL() becasue of a bug in Forte CC
137     compiler.
138 
139   RETURN
140    Position in 'pkg' after the packed length
141 */
142 
net_store_length(uchar * packet,ulonglong length)143 uchar *net_store_length(uchar *packet, ulonglong length)
144 {
145   if (length < (ulonglong) LL(251))
146   {
147     *packet=(uchar) length;
148     return packet+1;
149   }
150   /* 251 is reserved for NULL */
151   if (length < (ulonglong) LL(65536))
152   {
153     *packet++=252;
154     int2store(packet,(uint) length);
155     return packet+2;
156   }
157   if (length < (ulonglong) LL(16777216))
158   {
159     *packet++=253;
160     int3store(packet,(ulong) length);
161     return packet+3;
162   }
163   *packet++=254;
164   int8store(packet,length);
165   return packet+8;
166 }
167 
168