src/utils/unixsock.c

   1 /*
   2  * syscollector - src/utils/unixsock.c
   3  * Copyright (C) 2012 Sebastian 'tokkee' Harl <sh@tokkee.org>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  16  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  17  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  18  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
  19  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include "utils/unixsock.h"
  29 #include "utils/string.h"
  30
  31 #include <assert.h>
  32 #include <errno.h>
  33
  34 #include <stdarg.h>
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37
  38 #include <string.h>
  39 #include <strings.h>
  40
  41 #include <unistd.h>
  42
  43 #include <sys/socket.h>
  44 #include <sys/un.h>
  45
  46 /*
  47  * private data types
  48  */
  49
  50 struct sc_unixsock_client {
  51         char *path;
  52         FILE *fh;
  53
  54         int shutdown;
  55 };
  56
  57 #define SC_SHUT_RD   (1 << SHUT_RD)
  58 #define SC_SHUT_WR   (1 << SHUT_WR)
  59 #define SC_SHUT_RDWR (SC_SHUT_RD | SC_SHUT_WR)
  60
  61 /*
  62  * private helper functions
  63  */
  64
  65 static int
  66 sc_unixsock_get_column_count(const char *string, const char *delim)
  67 {
  68         int count = 1;
  69
  70         assert(string);
  71
  72         if ((! delim) || (*string == '\0'))
  73                 return 1;
  74
  75         if ((delim[0] == '\0') || (delim[1] == '\0')) {
  76                 while ((string = strchr(string, (int)delim[0]))) {
  77                         ++string;
  78                         ++count;
  79                 }
  80         }
  81         else {
  82                 while ((string = strpbrk(string, delim))) {
  83                         ++string;
  84                         ++count;
  85                 }
  86         }
  87         return count;
  88 } /* sc_unixsock_get_column_count */
  89
  90 static int
  91 sc_unixsock_parse_cell(char *string, int type, sc_data_t *data)
  92 {
  93         char *endptr = NULL;
  94
  95         switch (type) {
  96                 case SC_TYPE_INTEGER:
  97                         errno = 0;
  98                         data->data.integer = strtoll(string, &endptr, 0);
  99                         break;
 100                 case SC_TYPE_DECIMAL:
 101                         errno = 0;
 102                         data->data.decimal = strtod(string, &endptr);
 103                         break;
 104                 case SC_TYPE_STRING:
 105                         data->data.string = string;
 106                         break;
 107                 case SC_TYPE_DATETIME:
 108                         {
 109                                 double datetime = strtod(string, &endptr);
 110                                 data->data.datetime = DOUBLE_TO_SC_TIME(datetime);
 111                         }
 112                         break;
 113                 case SC_TYPE_BINARY:
 114                         /* we don't support any binary information containing 0-bytes */
 115                         data->data.binary.length = strlen(string);
 116                         data->data.binary.datum = (const unsigned char *)string;
 117                         break;
 118                 default:
 119                         fprintf(stderr, "unixsock: Unexpected type %i while "
 120                                         "parsing query result.\n", type);
 121                         return -1;
 122         }
 123
 124         if ((type == SC_TYPE_INTEGER) || (type == SC_TYPE_DECIMAL)
 125                         || (type == SC_TYPE_DATETIME)) {
 126                 if (errno || (string == endptr)) {
 127                         char errbuf[1024];
 128                         fprintf(stderr, "unixsock: Failed to parse string '%s' "
 129                                         "as numeric value (type %i): %s\n", string, type,
 130                                         sc_strerror(errno, errbuf, sizeof(errbuf)));
 131                         return -1;
 132                 }
 133                 else if (endptr && (*endptr != '\0'))
 134                         fprintf(stderr, "unixsock: Ignoring garbage after number "
 135                                         "while parsing numeric value (type %i): %s.\n",
 136                                         type, endptr);
 137         }
 138
 139         data->type = type;
 140         return 0;
 141 } /* sc_unixsock_parse_cell */
 142
 143 static int
 144 sc_unixsock_client_process_one_line(sc_unixsock_client_t *client,
 145                 char *line, sc_unixsock_client_data_cb callback,
 146                 sc_object_t *user_data, const char *delim,
 147                 int column_count, int *types)
 148 {
 149         sc_data_t data[column_count];
 150         char *orig_line = line;
 151
 152         int i;
 153
 154         assert(column_count > 0);
 155
 156         for (i = 0; i < column_count; ++i) {
 157                 char *next;
 158
 159                 if (! line) { /* this must no happen */
 160                         fprintf(stderr, "unixsock: Unexpected EOL while parsing line "
 161                                         "(expected %i columns delimited by '%s'; got %i): %s\n",
 162                                         column_count, delim, /* last line number */ i, orig_line);
 163                         return -1;
 164                 }
 165
 166                 if ((delim[0] == '\0') || (delim[1] == '\0'))
 167                         next = strchr(line, (int)delim[0]);
 168                 else
 169                         next = strpbrk(line, delim);
 170
 171                 if (next) {
 172                         *next = '\0';
 173                         ++next;
 174                 }
 175
 176                 if (sc_unixsock_parse_cell(line,
 177                                         types ? types[i] : SC_TYPE_STRING, &data[i]))
 178                         return -1;
 179
 180                 line = next;
 181         }
 182
 183         if (callback(client, (size_t)column_count, data, user_data))
 184                 return -1;
 185         return 0;
 186 } /* sc_unixsock_client_process_one_line */
 187
 188 /*
 189  * public API
 190  */
 191
 192 sc_unixsock_client_t *
 193 sc_unixsock_client_create(const char *path)
 194 {
 195         sc_unixsock_client_t *client;
 196
 197         if (! path)
 198                 return NULL;
 199
 200         client = malloc(sizeof(*client));
 201         if (! client)
 202                 return NULL;
 203         memset(client, 0, sizeof(*client));
 204         client->fh = NULL;
 205
 206         client->path = strdup(path);
 207         if (! client->path) {
 208                 sc_unixsock_client_destroy(client);
 209                 return NULL;
 210         }
 211
 212         client->shutdown = 0;
 213         return client;
 214 } /* sc_unixsock_client_create */
 215
 216 int
 217 sc_unixsock_client_connect(sc_unixsock_client_t *client)
 218 {
 219         struct sockaddr_un sa;
 220         int fd;
 221
 222         if ((! client) || (! client->path))
 223                 return -1;
 224
 225         memset(&sa, 0, sizeof(sa));
 226
 227         if (client->fh)
 228                 fclose(client->fh);
 229
 230         fd = socket(AF_UNIX, SOCK_STREAM, /* protocol = */ 0);
 231         if (fd < 0) {
 232                 char errbuf[1024];
 233                 fprintf(stderr, "unixsock: Failed to open socket: %s\n",
 234                                 sc_strerror(errno, errbuf, sizeof(errbuf)));
 235                 return -1;
 236         }
 237
 238         sa.sun_family = AF_UNIX;
 239         strncpy(sa.sun_path, client->path, sizeof(sa.sun_path));
 240         sa.sun_path[sizeof(sa.sun_path) - 1] = '\0';
 241
 242         if (connect(fd, (struct sockaddr *)&sa, sizeof(sa))) {
 243                 char errbuf[1024];
 244                 fprintf(stderr, "unixsock: Failed to connect to %s: %s\n",
 245                                 sa.sun_path, sc_strerror(errno, errbuf, sizeof(errbuf)));
 246                 close(fd);
 247                 return -1;
 248         }
 249
 250         client->fh = fdopen(fd, "r+");
 251         if (! client->fh) {
 252                 char errbuf[1024];
 253                 fprintf(stderr, "unixsock: Failed to open I/O stream for %s: %s\n",
 254                                 sa.sun_path, sc_strerror(errno, errbuf, sizeof(errbuf)));
 255                 close(fd);
 256                 return -1;
 257         }
 258
 259         client->shutdown = 0;
 260         return 0;
 261 } /* sc_unixsock_client_connect */
 262
 263 int
 264 sc_unixsock_client_send(sc_unixsock_client_t *client, const char *msg)
 265 {
 266         int status;
 267
 268         if ((! client) || (! client->fh))
 269                 return -1;
 270
 271         if (client->shutdown & SC_SHUT_WR) /* reconnect */
 272                 sc_unixsock_client_connect(client);
 273
 274         status = fprintf(client->fh, "%s\r\n", msg);
 275         if (status < 0) {
 276                 char errbuf[1024];
 277                 fprintf(stderr, "unixsock: Failed to write to socket (%s): %s\n",
 278                                 client->path, sc_strerror(errno, errbuf, sizeof(errbuf)));
 279                 return status;
 280         }
 281         return status;
 282 } /* sc_unixsock_client_send */
 283
 284 char *
 285 sc_unixsock_client_recv(sc_unixsock_client_t *client, char *buffer, size_t buflen)
 286 {
 287         if ((! client) || (! client->fh) || (! buffer))
 288                 return NULL;
 289
 290         if (client->shutdown & SC_SHUT_RD) /* reconnect */
 291                 sc_unixsock_client_connect(client);
 292
 293         buffer = fgets(buffer, (int)buflen - 1, client->fh);
 294         if (! buffer) {
 295                 if (! feof(client->fh)) {
 296                         char errbuf[1024];
 297                         fprintf(stderr, "unixsock: Failed to read from socket (%s): %s\n",
 298                                         client->path, sc_strerror(errno, errbuf, sizeof(errbuf)));
 299                 }
 300                 return buffer;
 301         }
 302         buffer[buflen - 1] = '\0';
 303
 304         buflen = strlen(buffer);
 305         while ((buffer[buflen - 1] == '\n') || (buffer[buflen - 1] == '\r')) {
 306                 buffer[buflen - 1] = '\0';
 307                 --buflen;
 308         }
 309         return buffer;
 310 } /* sc_unixsock_client_recv */
 311
 312 int
 313 sc_unixsock_client_process_lines(sc_unixsock_client_t *client,
 314                 sc_unixsock_client_data_cb callback, sc_object_t *user_data,
 315                 long int max_lines, const char *delim, int n_cols, ...)
 316 {
 317         int *types = NULL;
 318         int success = 0;
 319
 320         if ((! client) || (! client->fh) || (! callback))
 321                 return -1;
 322
 323         if (n_cols > 0) {
 324                 va_list ap;
 325                 int i;
 326
 327                 types = calloc((size_t)n_cols, sizeof(*types));
 328                 if (! types)
 329                         return -1;
 330
 331                 va_start(ap, n_cols);
 332
 333                 for (i = 0; i < n_cols; ++i) {
 334                         types[i] = va_arg(ap, int);
 335
 336                         if ((types[i] < 1) || (types[i] > SC_TYPE_BINARY)) {
 337                                 fprintf(stderr, "unixsock: Unknown column type %i while "
 338                                                 "processing response from the UNIX socket @ %s.\n",
 339                                                 types[i], client->path);
 340                                 va_end(ap);
 341                                 free(types);
 342                                 return -1;
 343                         }
 344                 }
 345
 346                 va_end(ap);
 347         }
 348
 349         while (42) {
 350                 char  buffer[1024];
 351                 char *line;
 352
 353                 int column_count;
 354
 355                 if (! max_lines)
 356                         break;
 357
 358                 if (max_lines > 0)
 359                         --max_lines;
 360
 361                 sc_unixsock_client_clearerr(client);
 362                 line = sc_unixsock_client_recv(client, buffer, sizeof(buffer));
 363
 364                 if (! line)
 365                         break;
 366
 367                 column_count = sc_unixsock_get_column_count(line, delim);
 368
 369                 if ((n_cols >= 0) && (n_cols != column_count)) {
 370                         fprintf(stderr, "unixsock: number of columns (%i) does not "
 371                                         "match the number of requested columns (%i) while "
 372                                         "processing response from the UNIX socket @ %s: %s\n",
 373                                         column_count, n_cols, client->path, line);
 374                         continue;
 375                 }
 376
 377                 if (column_count <= 0) /* no data */
 378                         continue;
 379
 380                 if (! sc_unixsock_client_process_one_line(client, line, callback,
 381                                         user_data, delim, column_count, types))
 382                         ++success;
 383         }
 384
 385         free(types);
 386
 387         if ((max_lines > 0)
 388                         || ((max_lines < 0) && (! sc_unixsock_client_eof(client)))
 389                         || sc_unixsock_client_error(client)) {
 390                 char errbuf[1024];
 391                 fprintf(stderr, "unixsock: Unexpected end of data while reading "
 392                                 "from socket (%s): %s\n", client->path,
 393                                 sc_strerror(errno, errbuf, sizeof(errbuf)));
 394                 return -1;
 395         }
 396         if (! success)
 397                 return -1;
 398         return 0;
 399 } /* sc_unixsock_client_process_lines */
 400
 401 int
 402 sc_unixsock_client_shutdown(sc_unixsock_client_t *client, int how)
 403 {
 404         int status;
 405
 406         if (! client) {
 407                 errno = ENOTSOCK;
 408                 return -1;
 409         }
 410
 411         fflush(client->fh);
 412         status = shutdown(fileno(client->fh), how);
 413
 414         if (! status) {
 415                 if (how == SHUT_RDWR)
 416                         client->shutdown |= SC_SHUT_RDWR;
 417                 else
 418                         client->shutdown |= 1 << how;
 419         }
 420         return status;
 421 } /* sc_unixsock_client_shutdown */
 422
 423 void
 424 sc_unixsock_client_clearerr(sc_unixsock_client_t *client)
 425 {
 426         if ((! client) || (! client->fh))
 427                 return;
 428         clearerr(client->fh);
 429 } /* sc_unixsock_client_clearerr */
 430
 431 int
 432 sc_unixsock_client_eof(sc_unixsock_client_t *client)
 433 {
 434         if ((! client) || (! client->fh)) {
 435                 errno = EBADF;
 436                 return -1;
 437         }
 438         return feof(client->fh);
 439 } /* sc_unixsock_client_eof */
 440
 441 int
 442 sc_unixsock_client_error(sc_unixsock_client_t *client)
 443 {
 444         if ((! client) || (! client->fh)) {
 445                 errno = EBADF;
 446                 return -1;
 447         }
 448         return ferror(client->fh);
 449 } /* sc_unixsock_client_error */
 450
 451 void
 452 sc_unixsock_client_destroy(sc_unixsock_client_t *client)
 453 {
 454         if (! client)
 455                 return;
 456
 457         if (client->path)
 458                 free(client->path);
 459         client->path = NULL;
 460
 461         if (client->fh)
 462                 fclose(client->fh);
 463         client->fh = NULL;
 464
 465         free(client);
 466 } /* sc_unixsock_client_destroy */
 467
 468 const char *
 469 sc_unixsock_client_path(sc_unixsock_client_t *client)
 470 {
 471         if (! client)
 472                 return NULL;
 473         return client->path;
 474 } /* sc_unixsock_client_path */
 475
 476 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 477