1 /***********************************************************************
2 * *
3 * This software is part of the ast package *
4 * Copyright (c) 1990-2011 AT&T Intellectual Property *
5 * and is licensed under the *
6 * Eclipse Public License, Version 1.0 *
7 * by AT&T Intellectual Property *
8 * *
9 * A copy of the License is available at *
10 * http://www.eclipse.org/org/documents/epl-v10.html *
11 * (with md5 checksum b35adb5213ca9657e911e9befb180842) *
12 * *
13 * Information and Software Systems Research *
14 * AT&T Research *
15 * Florham Park NJ *
16 * *
17 * Glenn Fowler <glenn.s.fowler@gmail.com> *
18 * *
19 ***********************************************************************/
20 #pragma prototyped
21 /*
22 * Glenn Fowler
23 * AT&T Research
24 *
25 * css - multiplex multiple clients on one filter server
26 */
27
28 static const char usage[] =
29 "[-?\n@(#)$Id: css (AT&T Research) 1998-05-01 $\n]"
30 USAGE_LICENSE
31 "[+NAME?css - multiplex multiple clients on one connect stream server]"
32 "[+DESCRIPTION?\bcss\b multiplexes multiple clients on one filter server."
33 " A filter server is a process that reads lines from the standard input"
34 " and writes result lines to the standard output. \aconnect-stream\a"
35 " is the connect stream path by which the filter service will be known.]"
36
37 "[t:timeout?The service will exit after a \atime\a period of client"
38 " inactivity.]:[time]"
39
40 "\n"
41 "\nconnect-stream command [ arg ... ]\n"
42 "\n"
43
44 "[+PROTOCOL?A filter service must follow a simple line oriented protocol. All"
45 " client lines are split into arguments and a number is inserted in the"
46 " second argument position. This number, followed by a space, must be"
47 " placed at the beginning of each line written by the filter server for"
48 " the given client request.]"
49
50 "[+SEE ALSO?\bcoshell\b(1), \bcs\b(1), \bss\b(1), \bcs\b(3)]"
51 ;
52
53 #include <css.h>
54 #include <ctype.h>
55 #include <error.h>
56 #include <proc.h>
57
58 typedef struct
59 {
60 Csid_t id;
61 int service;
62 } Connection_t;
63
64 typedef struct
65 {
66 Cssdisc_t disc;
67 Proc_t* proc;
68 Sfio_t* tmp;
69 } State_t;
70
71 static char buf[8 * 1024];
72
73 static int
acceptf(Css_t * css,Cssfd_t * fp,Csid_t * ip,char ** av,Cssdisc_t * disc)74 acceptf(Css_t* css, Cssfd_t* fp, Csid_t* ip, char** av, Cssdisc_t* disc)
75 {
76 register Connection_t* con;
77
78 NoP(av);
79 if (!(con = newof(0, Connection_t, 1, 0)))
80 return -1;
81 fp->data = con;
82 con->id = *ip;
83 return fp->fd;
84 }
85
86 static int
actionf(register Css_t * css,register Cssfd_t * fp,Cssdisc_t * disc)87 actionf(register Css_t* css, register Cssfd_t* fp, Cssdisc_t* disc)
88 {
89 register State_t* state = (State_t*)disc;
90 register Connection_t* con;
91 register char* s;
92 register char* t;
93 int n;
94 int i;
95
96 switch (fp->status)
97 {
98 case CS_POLL_CLOSE:
99 if (con = (Connection_t*)fp->data)
100 {
101 if (con->service)
102 error(ERROR_SYSTEM|3, "service termination exit");
103 free(con);
104 }
105 return 0;
106 case CS_POLL_READ:
107 con = (Connection_t*)fp->data;
108 if ((n = csread(css->state, fp->fd, buf, sizeof(buf) - 1, CS_LINE)) <= 0)
109 {
110 if (con->service)
111 error(ERROR_SYSTEM|3, "service termination exit");
112 return -1;
113 }
114 buf[n] = 0;
115 for (s = buf; isspace(*s); s++);
116 if (con->service)
117 {
118 for (i = 0; isdigit(*s); i = i * 10 + *s++ - '0');
119 for (; isspace(*s); s++);
120 if (*s && cssfd(css, i, 0))
121 {
122 n -= s - buf;
123 if (cswrite(css->state, i, s, n) != n)
124 cssfd(css, i, CS_POLL_CLOSE);
125 }
126 }
127 else if (*s == '!')
128 {
129 if ((n -= ++s - buf) > 0 && cswrite(css->state, state->proc->wfd, s, n) != n)
130 return -1;
131 }
132 else
133 {
134 for (t = s; *t && !isspace(*t); t++);
135 for (; isspace(*t); t++);
136 if (*s == 'Q' && !*t)
137 {
138 if (con->id.uid == geteuid())
139 error(3, "service quit exit");
140 }
141 else
142 {
143 n = sfprintf(state->tmp, "%-.*s%d %s", t - s, s, fp->fd, t);
144 if (!(s = sfstruse(state->tmp)))
145 return -1;
146 if (cswrite(css->state, state->proc->wfd, s, n) != n)
147 return -1;
148 }
149 }
150 return 1;
151 }
152 return 0;
153 }
154
155 static int
exceptf(Css_t * css,unsigned long op,unsigned long arg,Cssdisc_t * disc)156 exceptf(Css_t* css, unsigned long op, unsigned long arg, Cssdisc_t* disc)
157 {
158 switch (op)
159 {
160 case CSS_INTERRUPT:
161 error(ERROR_SYSTEM|3, "%s: interrupt exit", fmtsignal(arg));
162 return 0;
163 case CSS_DORMANT:
164 error(2, "service dormant exit");
165 exit(0);
166 }
167 error(ERROR_SYSTEM|3, "poll error op=0x%08x arg=0x%08x", op, arg);
168 return -1;
169 }
170
171
172 int
main(int argc,char ** argv)173 main(int argc, char** argv)
174 {
175 Css_t* css;
176 Cssfd_t* fp;
177 Connection_t* con;
178 char* e;
179 State_t state;
180
181 NoP(argc);
182 error_info.id = "css";
183 memset(&state, 0, sizeof(state));
184 state.disc.version = CSS_VERSION;
185 state.disc.flags = CSS_DAEMON|CSS_ERROR|CSS_INTERRUPT;
186 state.disc.acceptf = acceptf;
187 state.disc.actionf = actionf;
188 state.disc.errorf = errorf;
189 state.disc.exceptf = exceptf;
190 for (;;)
191 {
192 switch (optget(argv, usage))
193 {
194 case 't':
195 state.disc.timeout = strelapsed(opt_info.arg, &e, 1);
196 if (*e)
197 error(3, "%s: invalid timeout value", opt_info.arg);
198 state.disc.flags |= CSS_DORMANT;
199 continue;
200 case '?':
201 error(ERROR_USAGE|4, "%s", opt_info.arg);
202 continue;
203 case ':':
204 error(2, "%s", opt_info.arg);
205 continue;
206 }
207 break;
208 }
209 argv += opt_info.index;
210 if (!argv[0] || !argv[1])
211 error(ERROR_USAGE|4, "%s", optusage(NiL));
212 if (!(state.tmp = sfstropen()))
213 error(ERROR_SYSTEM|3, "out of space [tmp stream]");
214 if (!(state.proc = procopen(argv[1], argv + 1, NiL, NiL, PROC_READ|PROC_WRITE)))
215 error(ERROR_SYSTEM|3, "%s: cannot execute", argv[1]);
216 if (!(css = cssopen(argv[0], &state.disc)))
217 return 1;
218 if (!(fp = cssfd(css, state.proc->rfd, CS_POLL_READ)))
219 error(ERROR_SYSTEM|3, "%s: cannot poll output", argv[1]);
220 if (!(con = newof(0, Connection_t, 1, 0)))
221 error(ERROR_SYSTEM|3, "out of space");
222 fp->data = con;
223 con->service = 1;
224 csspoll(CS_NEVER, 0);
225 return 1;
226 }
227