src/server/tcl_server.c

   1 /***************************************************************************
   2  *   Copyright (C) 2010 Øyvind 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, see <http://www.gnu.org/licenses/>. *
  17  ***************************************************************************/
  18
  19 #ifdef HAVE_CONFIG_H
  20 #include "config.h"
  21 #endif
  22
  23 #include "tcl_server.h"
  24 #include <target/target.h>
  25 #include <helper/binarybuffer.h>
  26
  27 #define TCL_SERVER_VERSION              "TCL Server 0.1"
  28 #define TCL_LINE_INITIAL                (4*1024)
  29 #define TCL_LINE_MAX                    (4*1024*1024)
  30
  31 struct tcl_connection {
  32         int tc_linedrop;
  33         int tc_lineoffset;
  34         int tc_line_size;
  35         char *tc_line;
  36         int tc_outerror;/* flag an output error */
  37         enum target_state tc_laststate;
  38         bool tc_notify;
  39         bool tc_trace;
  40 };
  41
  42 static char *tcl_port;
  43
  44 /* handlers */
  45 static int tcl_new_connection(struct connection *connection);
  46 static int tcl_input(struct connection *connection);
  47 static int tcl_output(struct connection *connection, const void *buf, ssize_t len);
  48 static int tcl_closed(struct connection *connection);
  49
  50 static int tcl_target_callback_event_handler(struct target *target,
  51                 enum target_event event, void *priv)
  52 {
  53         struct connection *connection = priv;
  54         struct tcl_connection *tclc;
  55         char buf[256];
  56
  57         tclc = connection->priv;
  58
  59         if (tclc->tc_notify) {
  60                 snprintf(buf, sizeof(buf), "type target_event event %s\r\n\x1a", target_event_name(event));
  61                 tcl_output(connection, buf, strlen(buf));
  62         }
  63
  64         if (tclc->tc_laststate != target->state) {
  65                 tclc->tc_laststate = target->state;
  66                 if (tclc->tc_notify) {
  67                         snprintf(buf, sizeof(buf), "type target_state state %s\r\n\x1a", target_state_name(target));
  68                         tcl_output(connection, buf, strlen(buf));
  69                 }
  70         }
  71
  72         return ERROR_OK;
  73 }
  74
  75 static int tcl_target_callback_reset_handler(struct target *target,
  76                 enum target_reset_mode reset_mode, void *priv)
  77 {
  78         struct connection *connection = priv;
  79         struct tcl_connection *tclc;
  80         char buf[256];
  81
  82         tclc = connection->priv;
  83
  84         if (tclc->tc_notify) {
  85                 snprintf(buf, sizeof(buf), "type target_reset mode %s\r\n\x1a", target_reset_mode_name(reset_mode));
  86                 tcl_output(connection, buf, strlen(buf));
  87         }
  88
  89         return ERROR_OK;
  90 }
  91
  92 static int tcl_target_callback_trace_handler(struct target *target,
  93                 size_t len, uint8_t *data, void *priv)
  94 {
  95         struct connection *connection = priv;
  96         struct tcl_connection *tclc;
  97         char *header = "type target_trace data ";
  98         char *trailer = "\r\n\x1a";
  99         size_t hex_len = len * 2 + 1;
 100         size_t max_len = hex_len + strlen(header) + strlen(trailer);
 101         char *buf, *hex;
 102
 103         tclc = connection->priv;
 104
 105         if (tclc->tc_trace) {
 106                 hex = malloc(hex_len);
 107                 buf = malloc(max_len);
 108                 hexify(hex, data, len, hex_len);
 109                 snprintf(buf, max_len, "%s%s%s", header, hex, trailer);
 110                 tcl_output(connection, buf, strlen(buf));
 111                 free(hex);
 112                 free(buf);
 113         }
 114
 115         return ERROR_OK;
 116 }
 117
 118 /* write data out to a socket.
 119  *
 120  * this is a blocking write, so the return value must equal the length, if
 121  * that is not the case then flag the connection with an output error.
 122  */
 123 int tcl_output(struct connection *connection, const void *data, ssize_t len)
 124 {
 125         ssize_t wlen;
 126         struct tcl_connection *tclc;
 127
 128         tclc = connection->priv;
 129         if (tclc->tc_outerror)
 130                 return ERROR_SERVER_REMOTE_CLOSED;
 131
 132         wlen = connection_write(connection, data, len);
 133
 134         if (wlen == len)
 135                 return ERROR_OK;
 136
 137         LOG_ERROR("error during write: %d != %d", (int)wlen, (int)len);
 138         tclc->tc_outerror = 1;
 139         return ERROR_SERVER_REMOTE_CLOSED;
 140 }
 141
 142 /* connections */
 143 static int tcl_new_connection(struct connection *connection)
 144 {
 145         struct tcl_connection *tclc;
 146
 147         tclc = calloc(1, sizeof(struct tcl_connection));
 148         if (tclc == NULL)
 149                 return ERROR_CONNECTION_REJECTED;
 150
 151         tclc->tc_line_size = TCL_LINE_INITIAL;
 152         tclc->tc_line = malloc(tclc->tc_line_size);
 153         if (tclc->tc_line == NULL) {
 154                 free(tclc);
 155                 return ERROR_CONNECTION_REJECTED;
 156         }
 157
 158         connection->priv = tclc;
 159
 160         struct target *target = get_current_target_or_null(connection->cmd_ctx);
 161         if (target != NULL)
 162                 tclc->tc_laststate = target->state;
 163
 164         /* store the connection object on cmd_ctx so we can access it from command handlers */
 165         connection->cmd_ctx->output_handler_priv = connection;
 166
 167         target_register_event_callback(tcl_target_callback_event_handler, connection);
 168         target_register_reset_callback(tcl_target_callback_reset_handler, connection);
 169         target_register_trace_callback(tcl_target_callback_trace_handler, connection);
 170
 171         return ERROR_OK;
 172 }
 173
 174 static int tcl_input(struct connection *connection)
 175 {
 176         Jim_Interp *interp = (Jim_Interp *)connection->cmd_ctx->interp;
 177         int retval;
 178         int i;
 179         ssize_t rlen;
 180         const char *result;
 181         int reslen;
 182         struct tcl_connection *tclc;
 183         unsigned char in[256];
 184         char *tc_line_new;
 185         int tc_line_size_new;
 186
 187         rlen = connection_read(connection, &in, sizeof(in));
 188         if (rlen <= 0) {
 189                 if (rlen < 0)
 190                         LOG_ERROR("error during read: %s", strerror(errno));
 191                 return ERROR_SERVER_REMOTE_CLOSED;
 192         }
 193
 194         tclc = connection->priv;
 195         if (tclc == NULL)
 196                 return ERROR_CONNECTION_REJECTED;
 197
 198         /* push as much data into the line as possible */
 199         for (i = 0; i < rlen; i++) {
 200                 /* buffer the data */
 201                 tclc->tc_line[tclc->tc_lineoffset] = in[i];
 202                 if (tclc->tc_lineoffset < tclc->tc_line_size) {
 203                         tclc->tc_lineoffset++;
 204                 } else if (tclc->tc_line_size >= TCL_LINE_MAX) {
 205                         /* maximum line size reached, drop line */
 206                         tclc->tc_linedrop = 1;
 207                 } else {
 208                         /* grow line buffer: exponential below 1 MB, linear above */
 209                         if (tclc->tc_line_size <= 1*1024*1024)
 210                                 tc_line_size_new = tclc->tc_line_size * 2;
 211                         else
 212                                 tc_line_size_new = tclc->tc_line_size + 1*1024*1024;
 213
 214                         if (tc_line_size_new > TCL_LINE_MAX)
 215                                 tc_line_size_new = TCL_LINE_MAX;
 216
 217                         tc_line_new = realloc(tclc->tc_line, tc_line_size_new);
 218                         if (tc_line_new == NULL) {
 219                                 tclc->tc_linedrop = 1;
 220                         } else {
 221                                 tclc->tc_line = tc_line_new;
 222                                 tclc->tc_line_size = tc_line_size_new;
 223                                 tclc->tc_lineoffset++;
 224                         }
 225
 226                 }
 227
 228                 /* ctrl-z is end of command. When testing from telnet, just
 229                  * press ctrl-z a couple of times first to put telnet into the
 230                  * mode where it will send 0x1a in response to pressing ctrl-z
 231                  */
 232                 if (in[i] != '\x1a')
 233                         continue;
 234
 235                 /* process the line */
 236                 if (tclc->tc_linedrop) {
 237 #define ESTR "line too long\n"
 238                         retval = tcl_output(connection, ESTR, sizeof(ESTR));
 239                         if (retval != ERROR_OK)
 240                                 return retval;
 241 #undef ESTR
 242                 } else {
 243                         tclc->tc_line[tclc->tc_lineoffset-1] = '\0';
 244                         command_run_line(connection->cmd_ctx, tclc->tc_line);
 245                         result = Jim_GetString(Jim_GetResult(interp), &reslen);
 246                         retval = tcl_output(connection, result, reslen);
 247                         if (retval != ERROR_OK)
 248                                 return retval;
 249                         /* Always output ctrl-z as end of line to allow multiline results */
 250                         tcl_output(connection, "\x1a", 1);
 251                 }
 252
 253                 tclc->tc_lineoffset = 0;
 254                 tclc->tc_linedrop = 0;
 255         }
 256
 257         return ERROR_OK;
 258 }
 259
 260 static int tcl_closed(struct connection *connection)
 261 {
 262         struct tcl_connection *tclc;
 263         tclc = connection->priv;
 264
 265         /* cleanup connection context */
 266         if (tclc) {
 267                 free(tclc->tc_line);
 268                 free(tclc);
 269                 connection->priv = NULL;
 270         }
 271
 272         target_unregister_event_callback(tcl_target_callback_event_handler, connection);
 273         target_unregister_reset_callback(tcl_target_callback_reset_handler, connection);
 274         target_unregister_trace_callback(tcl_target_callback_trace_handler, connection);
 275
 276         return ERROR_OK;
 277 }
 278
 279 int tcl_init(void)
 280 {
 281         if (strcmp(tcl_port, "disabled") == 0) {
 282                 LOG_INFO("tcl server disabled");
 283                 return ERROR_OK;
 284         }
 285
 286         return add_service("tcl", tcl_port, CONNECTION_LIMIT_UNLIMITED,
 287                 &tcl_new_connection, &tcl_input,
 288                 &tcl_closed, NULL);
 289 }
 290
 291 COMMAND_HANDLER(handle_tcl_port_command)
 292 {
 293         return CALL_COMMAND_HANDLER(server_pipe_command, &tcl_port);
 294 }
 295
 296 COMMAND_HANDLER(handle_tcl_notifications_command)
 297 {
 298         struct connection *connection = NULL;
 299         struct tcl_connection *tclc = NULL;
 300
 301         if (CMD_CTX->output_handler_priv != NULL)
 302                 connection = CMD_CTX->output_handler_priv;
 303
 304         if (connection != NULL && !strcmp(connection->service->name, "tcl")) {
 305                 tclc = connection->priv;
 306                 return CALL_COMMAND_HANDLER(handle_command_parse_bool, &tclc->tc_notify, "Target Notification output ");
 307         } else {
 308                 LOG_ERROR("%s: can only be called from the tcl server", CMD_NAME);
 309                 return ERROR_COMMAND_SYNTAX_ERROR;
 310         }
 311 }
 312
 313 COMMAND_HANDLER(handle_tcl_trace_command)
 314 {
 315         struct connection *connection = NULL;
 316         struct tcl_connection *tclc = NULL;
 317
 318         if (CMD_CTX->output_handler_priv != NULL)
 319                 connection = CMD_CTX->output_handler_priv;
 320
 321         if (connection != NULL && !strcmp(connection->service->name, "tcl")) {
 322                 tclc = connection->priv;
 323                 return CALL_COMMAND_HANDLER(handle_command_parse_bool, &tclc->tc_trace, "Target trace output ");
 324         } else {
 325                 LOG_ERROR("%s: can only be called from the tcl server", CMD_NAME);
 326                 return ERROR_COMMAND_SYNTAX_ERROR;
 327         }
 328 }
 329
 330 static const struct command_registration tcl_command_handlers[] = {
 331         {
 332                 .name = "tcl_port",
 333                 .handler = handle_tcl_port_command,
 334                 .mode = COMMAND_ANY,
 335                 .help = "Specify port on which to listen "
 336                         "for incoming Tcl syntax.  "
 337                         "Read help on 'gdb_port'.",
 338                 .usage = "[port_num]",
 339         },
 340         {
 341                 .name = "tcl_notifications",
 342                 .handler = handle_tcl_notifications_command,
 343                 .mode = COMMAND_EXEC,
 344                 .help = "Target Notification output",
 345                 .usage = "[on|off]",
 346         },
 347         {
 348                 .name = "tcl_trace",
 349                 .handler = handle_tcl_trace_command,
 350                 .mode = COMMAND_EXEC,
 351                 .help = "Target trace output",
 352                 .usage = "[on|off]",
 353         },
 354         COMMAND_REGISTRATION_DONE
 355 };
 356
 357 int tcl_register_commands(struct command_context *cmd_ctx)
 358 {
 359         tcl_port = strdup("6666");
 360         return register_commands(cmd_ctx, NULL, tcl_command_handlers);
 361 }
 362
 363 void tcl_service_free(void)
 364 {
 365         free(tcl_port);
 366 }