1 /*++
2 /* NAME
3 /* memcache_proto 3
4 /* SUMMARY
5 /* memcache low-level protocol
6 /* SYNOPSIS
7 /* #include <memcache_proto.h>
8 /*
9 /* int memcache_get(fp, buf, len)
10 /* VSTREAM *fp;
11 /* VSTRING *buf;
12 /* ssize_t len;
13 /*
14 /* int memcache_printf(fp, format, ...)
15 /* VSTREAM *fp;
16 /* const char *format;
17 /*
18 /* int memcache_vprintf(fp, format, ap)
19 /* VSTREAM *fp;
20 /* const char *format;
21 /* va_list ap;
22 /*
23 /* int memcache_fread(fp, buf, len)
24 /* VSTREAM *fp;
25 /* VSTRING *buf;
26 /* ssize_t len;
27 /*
28 /* int memcache_fwrite(fp, buf, len)
29 /* VSTREAM *fp;
30 /* const char *buf;
31 /* ssize_t len;
32 /* DESCRIPTION
33 /* This module implements the low-level memcache protocol.
34 /* All functions return -1 on error and 0 on succcess.
35 /* SEE ALSO
36 /* smtp_proto(3) SMTP low-level protocol.
37 /* AUTHOR(S)
38 /* Wietse Venema
39 /* IBM T.J. Watson Research
40 /* P.O. Box 704
41 /* Yorktown Heights, NY 10598, USA
42 /*
43 /* Wietse Venema
44 /* Google, Inc.
45 /* 111 8th Avenue
46 /* New York, NY 10011, USA
47 /*--*/
48
49 #include <sys_defs.h>
50
51 /* Utility library. */
52
53 #include <msg.h>
54 #include <vstream.h>
55 #include <vstring.h>
56 #include <vstring_vstream.h>
57 #include <compat_va_copy.h>
58
59 /* Application-specific. */
60
61 #include <memcache_proto.h>
62
63 #define STR(x) vstring_str(x)
64 #define LEN(x) VSTRING_LEN(x)
65
66 /* memcache_get - read one line from peer */
67
memcache_get(VSTREAM * stream,VSTRING * vp,ssize_t bound)68 int memcache_get(VSTREAM *stream, VSTRING *vp, ssize_t bound)
69 {
70 int last_char;
71 int next_char;
72
73 last_char = (bound == 0 ? vstring_get(vp, stream) :
74 vstring_get_bound(vp, stream, bound));
75
76 switch (last_char) {
77
78 /*
79 * Do some repair in the rare case that we stopped reading in the
80 * middle of the CRLF record terminator.
81 */
82 case '\r':
83 if ((next_char = VSTREAM_GETC(stream)) == '\n') {
84 VSTRING_ADDCH(vp, '\n');
85 /* FALLTRHOUGH */
86 } else {
87 if (next_char != VSTREAM_EOF)
88 vstream_ungetc(stream, next_char);
89
90 /*
91 * Input too long, or EOF
92 */
93 default:
94 if (msg_verbose)
95 msg_info("%s got %s", VSTREAM_PATH(stream),
96 LEN(vp) < bound ? "EOF" : "input too long");
97 return (-1);
98 }
99
100 /*
101 * Strip off the record terminator: either CRLF or just bare LF.
102 */
103 case '\n':
104 vstring_truncate(vp, VSTRING_LEN(vp) - 1);
105 if (VSTRING_LEN(vp) > 0 && vstring_end(vp)[-1] == '\r')
106 vstring_truncate(vp, VSTRING_LEN(vp) - 1);
107 VSTRING_TERMINATE(vp);
108 if (msg_verbose)
109 msg_info("%s got: %s", VSTREAM_PATH(stream), STR(vp));
110 return (0);
111 }
112 }
113
114 /* memcache_fwrite - write one blob to peer */
115
memcache_fwrite(VSTREAM * stream,const char * cp,ssize_t todo)116 int memcache_fwrite(VSTREAM *stream, const char *cp, ssize_t todo)
117 {
118
119 /*
120 * Sanity check.
121 */
122 if (todo < 0)
123 msg_panic("memcache_fwrite: negative todo %ld", (long) todo);
124
125 /*
126 * Do the I/O.
127 */
128 if (msg_verbose)
129 msg_info("%s write: %.*s", VSTREAM_PATH(stream), (int) todo, cp);
130 if (vstream_fwrite(stream, cp, todo) != todo
131 || vstream_fputs("\r\n", stream) == VSTREAM_EOF)
132 return (-1);
133 else
134 return (0);
135 }
136
137 /* memcache_fread - read one blob from peer */
138
memcache_fread(VSTREAM * stream,VSTRING * buf,ssize_t todo)139 int memcache_fread(VSTREAM *stream, VSTRING *buf, ssize_t todo)
140 {
141
142 /*
143 * Sanity check.
144 */
145 if (todo < 0)
146 msg_panic("memcache_fread: negative todo %ld", (long) todo);
147
148 /*
149 * Do the I/O.
150 */
151 if (vstream_fread_buf(stream, buf, todo) != todo
152 || VSTREAM_GETC(stream) != '\r'
153 || VSTREAM_GETC(stream) != '\n') {
154 if (msg_verbose)
155 msg_info("%s read: error", VSTREAM_PATH(stream));
156 return (-1);
157 } else {
158 VSTRING_TERMINATE(buf);
159 if (msg_verbose)
160 msg_info("%s read: %s", VSTREAM_PATH(stream), STR(buf));
161 return (0);
162 }
163 }
164
165 /* memcache_vprintf - write one line to peer */
166
memcache_vprintf(VSTREAM * stream,const char * fmt,va_list ap)167 int memcache_vprintf(VSTREAM *stream, const char *fmt, va_list ap)
168 {
169
170 /*
171 * Do the I/O.
172 */
173 vstream_vfprintf(stream, fmt, ap);
174 vstream_fputs("\r\n", stream);
175 if (vstream_ferror(stream))
176 return (-1);
177 else
178 return (0);
179 }
180
181 /* memcache_printf - write one line to peer */
182
memcache_printf(VSTREAM * stream,const char * fmt,...)183 int memcache_printf(VSTREAM *stream, const char *fmt,...)
184 {
185 va_list ap;
186 int ret;
187
188 va_start(ap, fmt);
189
190 if (msg_verbose) {
191 VSTRING *buf = vstring_alloc(100);
192 va_list ap2;
193
194 VA_COPY(ap2, ap);
195 vstring_vsprintf(buf, fmt, ap2);
196 va_end(ap2);
197 msg_info("%s write: %s", VSTREAM_PATH(stream), STR(buf));
198 vstring_free(buf);
199 }
200
201 /*
202 * Do the I/O.
203 */
204 ret = memcache_vprintf(stream, fmt, ap);
205 va_end(ap);
206 return (ret);
207 }
208