tcl_server: switch to ctrl-z
[fw/openocd] / src / server / tcl_server.c
1 /***************************************************************************
2  *   Copyright (C) 2010 Ã˜yvind Harboe                                      *
3  *   oyvind.harboe@zylin.com                                               *
4  *                                                                         *
5  *   This program is free software; you can redistribute it and/or modify  *
6  *   it under the terms of the GNU General Public License as published by  *
7  *   the Free Software Foundation; either version 2 of the License, or     *
8  *   (at your option) any later version.                                   *
9  *                                                                         *
10  *   This program is distributed in the hope that it will be useful,       *
11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
13  *   GNU General Public License for more details.                          *
14  *                                                                         *
15  *   You should have received a copy of the GNU General Public License     *
16  *   along with this program; if not, write to the                         *
17  *   Free Software Foundation, Inc.,                                       *
18  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
19  ***************************************************************************/
20
21 #ifdef HAVE_CONFIG_H
22 #include "config.h"
23 #endif
24
25 #include "tcl_server.h"
26
27
28 #define TCL_SERVER_VERSION      "TCL Server 0.1"
29 #define TCL_MAX_LINE            (4096)
30
31 struct tcl_connection {
32         int tc_linedrop;
33         int tc_lineoffset;
34         char tc_line[TCL_MAX_LINE];
35         int tc_outerror; /* flag an output error */
36 };
37
38 static unsigned short tcl_port = 6666;
39
40 /* handlers */
41 static int tcl_new_connection(struct connection *connection);
42 static int tcl_input(struct connection *connection);
43 static int tcl_output(struct connection *connection, const void *buf, ssize_t len);
44 static int tcl_closed(struct connection *connection);
45
46 /* write data out to a socket.
47  *
48  * this is a blocking write, so the return value must equal the length, if
49  * that is not the case then flag the connection with an output error.
50  */
51 int tcl_output(struct connection *connection, const void *data, ssize_t len)
52 {
53         ssize_t wlen;
54         struct tcl_connection *tclc;
55
56         tclc = connection->priv;
57         if (tclc->tc_outerror)
58                 return ERROR_SERVER_REMOTE_CLOSED;
59
60         wlen = write_socket(connection->fd, data, len);
61         if (wlen == len)
62                 return ERROR_OK;
63
64         LOG_ERROR("error during write: %d != %d", (int)wlen, (int)len);
65         tclc->tc_outerror = 1;
66         return ERROR_SERVER_REMOTE_CLOSED;
67 }
68
69 /* connections */
70 static int tcl_new_connection(struct connection *connection)
71 {
72         struct tcl_connection *tclc;
73
74         tclc = malloc(sizeof(struct tcl_connection));
75         if (tclc == NULL)
76                 return ERROR_CONNECTION_REJECTED;
77
78         memset(tclc, 0, sizeof(struct tcl_connection));
79         connection->priv = tclc;
80         return ERROR_OK;
81 }
82
83 static int tcl_input(struct connection *connection)
84 {
85         Jim_Interp *interp = (Jim_Interp *)connection->cmd_ctx->interp;
86         int retval;
87         int i;
88         ssize_t rlen;
89         const char *result;
90         int reslen;
91         struct tcl_connection *tclc;
92         unsigned char in[256];
93
94         rlen = read_socket(connection->fd, &in, sizeof(in));
95         if (rlen <= 0) {
96                 if (rlen < 0)
97                         LOG_ERROR("error during read: %s", strerror(errno));
98                 return ERROR_SERVER_REMOTE_CLOSED;
99         }
100
101         tclc = connection->priv;
102         if (tclc == NULL)
103                 return ERROR_CONNECTION_REJECTED;
104
105         /* push as much data into the line as possible */
106         for (i = 0; i < rlen; i++)
107         {
108                 /* buffer the data */
109                 tclc->tc_line[tclc->tc_lineoffset] = in[i];
110                 if (tclc->tc_lineoffset < TCL_MAX_LINE)
111                         tclc->tc_lineoffset++;
112                 else
113                         tclc->tc_linedrop = 1;
114
115                 /* ctrl-z is end of command. When testing from telnet, just
116                  * press ctrl-z a couple of times first to put telnet into the
117                  * mode where it will send 0x1a in response to pressing ctrl-z
118                  */
119                 if (in[i] != '\x1a')
120                         continue;
121
122                 /* process the line */
123                 if (tclc->tc_linedrop) {
124 #define ESTR "line too long\n"
125                         retval = tcl_output(connection, ESTR, sizeof(ESTR));
126                         if (retval != ERROR_OK)
127                                 return retval;
128 #undef ESTR
129                 }
130                 else {
131                         tclc->tc_line[tclc->tc_lineoffset-1] = '\0';
132                         LOG_DEBUG("Executing script:\n %s", tclc->tc_line);
133                         retval = Jim_Eval_Named(interp, tclc->tc_line, "remote:connection",1);
134                         LOG_DEBUG("Result: %d\n %s", retval, Jim_GetString(Jim_GetResult(interp), &reslen));
135                         result = Jim_GetString(Jim_GetResult(interp), &reslen);
136                         retval = tcl_output(connection, result, reslen);
137                         if (retval != ERROR_OK)
138                                 return retval;
139                         /* Always output ctrl-d as end of line to allow multiline results */
140                         tcl_output(connection, "\x1a", 1);
141                 }
142
143                 tclc->tc_lineoffset = 0;
144                 tclc->tc_linedrop = 0;
145         }
146
147         return ERROR_OK;
148 }
149
150 static int tcl_closed(struct connection *connection)
151 {
152         /* cleanup connection context */
153         if (connection->priv) {
154                 free(connection->priv);
155                 connection->priv = NULL;
156         }
157         return ERROR_OK;
158 }
159
160 int tcl_init(void)
161 {
162         int retval;
163
164         if (tcl_port == 0)
165         {
166                 LOG_INFO("tcl port disabled");
167                 return ERROR_OK;
168         }
169
170         retval = add_service("tcl", CONNECTION_TCP, tcl_port, 1,
171                         &tcl_new_connection, &tcl_input,
172                         &tcl_closed, NULL);
173         return retval;
174 }
175
176 COMMAND_HANDLER(handle_tcl_port_command)
177 {
178         return CALL_COMMAND_HANDLER(server_port_command, &tcl_port);
179 }
180
181 static const struct command_registration tcl_command_handlers[] = {
182         {
183                 .name = "tcl_port",
184                 .handler = handle_tcl_port_command,
185                 .mode = COMMAND_CONFIG,
186                 .help = "Specify port on which to listen "
187                         "for incoming Tcl syntax.  "
188                         "No arguments reports Tcl port; zero disables.",
189                 .usage = "[port_num]",
190         },
191         COMMAND_REGISTRATION_DONE
192 };
193
194 int tcl_register_commands(struct command_context *cmd_ctx)
195 {
196         return register_commands(cmd_ctx, NULL, tcl_command_handlers);
197 }