src/utils/unixsock.c

   1 /*
   2  * SysDB - 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 #if HAVE_CONFIG_H
  29 #       include "config.h"
  30 #endif /* HAVE_CONFIG_H */
  31
  32 #include "utils/error.h"
  33 #include "utils/unixsock.h"
  34
  35 #include <assert.h>
  36 #include <errno.h>
  37
  38 #include <stdarg.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41
  42 #include <string.h>
  43 #include <strings.h>
  44
  45 #include <unistd.h>
  46
  47 #include <sys/socket.h>
  48 #include <sys/un.h>
  49
  50 /*
  51  * private data types
  52  */
  53
  54 struct sdb_unixsock_client {
  55         char *path;
  56         FILE *fh;
  57
  58         int shutdown;
  59 };
  60
  61 #define SDB_SHUT_RD   (1 << SHUT_RD)
  62 #define SDB_SHUT_WR   (1 << SHUT_WR)
  63 #define SDB_SHUT_RDWR (SDB_SHUT_RD | SDB_SHUT_WR)
  64
  65 /*
  66  * private helper functions
  67  */
  68
  69 static int
  70 sdb_unixsock_get_column_count(const char *string, const char *delim)
  71 {
  72         int count = 1;
  73
  74         assert(string);
  75
  76         if ((! delim) || (*string == '\0'))
  77                 return 1;
  78
  79         if ((delim[0] == '\0') || (delim[1] == '\0')) {
  80                 while ((string = strchr(string, (int)delim[0]))) {
  81                         ++string;
  82                         ++count;
  83                 }
  84         }
  85         else {
  86                 while ((string = strpbrk(string, delim))) {
  87                         ++string;
  88                         ++count;
  89                 }
  90         }
  91         return count;
  92 } /* sdb_unixsock_get_column_count */
  93
  94 static int
  95 sdb_unixsock_client_process_one_line(sdb_unixsock_client_t *client,
  96                 char *line, sdb_unixsock_client_data_cb callback,
  97                 sdb_object_t *user_data, const char *delim,
  98                 int column_count, int *types)
  99 {
 100         sdb_data_t data[column_count];
 101         char *orig_line = line;
 102
 103         int i;
 104
 105         assert(column_count > 0);
 106
 107         for (i = 0; i < column_count; ++i) {
 108                 char *next;
 109
 110                 if (! line) { /* this must no happen */
 111                         sdb_log(SDB_LOG_ERR, "unixsock: Unexpected EOL while "
 112                                         "parsing line (expected %i columns delimited by '%s'; "
 113                                         "got %i): %s", column_count, delim,
 114                                         /* last line number */ i, orig_line);
 115                         return -1;
 116                 }
 117
 118                 if ((delim[0] == '\0') || (delim[1] == '\0'))
 119                         next = strchr(line, (int)delim[0]);
 120                 else
 121                         next = strpbrk(line, delim);
 122
 123                 if (next) {
 124                         *next = '\0';
 125                         ++next;
 126                 }
 127
 128                 if (sdb_data_parse(line,
 129                                         types ? types[i] : SDB_TYPE_STRING, &data[i]))
 130                         return -1;
 131
 132                 line = next;
 133         }
 134
 135         if (callback(client, (size_t)column_count, data, user_data))
 136                 return -1;
 137         return 0;
 138 } /* sdb_unixsock_client_process_one_line */
 139
 140 /*
 141  * public API
 142  */
 143
 144 sdb_unixsock_client_t *
 145 sdb_unixsock_client_create(const char *path)
 146 {
 147         sdb_unixsock_client_t *client;
 148
 149         if (! path)
 150                 return NULL;
 151
 152         client = malloc(sizeof(*client));
 153         if (! client)
 154                 return NULL;
 155         memset(client, 0, sizeof(*client));
 156         client->fh = NULL;
 157
 158         client->path = strdup(path);
 159         if (! client->path) {
 160                 sdb_unixsock_client_destroy(client);
 161                 return NULL;
 162         }
 163
 164         client->shutdown = 0;
 165         return client;
 166 } /* sdb_unixsock_client_create */
 167
 168 int
 169 sdb_unixsock_client_connect(sdb_unixsock_client_t *client)
 170 {
 171         struct sockaddr_un sa;
 172         int fd;
 173
 174         if ((! client) || (! client->path))
 175                 return -1;
 176
 177         memset(&sa, 0, sizeof(sa));
 178
 179         if (client->fh)
 180                 fclose(client->fh);
 181
 182         fd = socket(AF_UNIX, SOCK_STREAM, /* protocol = */ 0);
 183         if (fd < 0) {
 184                 char errbuf[1024];
 185                 sdb_log(SDB_LOG_ERR, "unixsock: Failed to open socket: %s",
 186                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 187                 return -1;
 188         }
 189
 190         sa.sun_family = AF_UNIX;
 191         strncpy(sa.sun_path, client->path, sizeof(sa.sun_path));
 192         sa.sun_path[sizeof(sa.sun_path) - 1] = '\0';
 193
 194         if (connect(fd, (struct sockaddr *)&sa, sizeof(sa))) {
 195                 char errbuf[1024];
 196                 sdb_log(SDB_LOG_ERR, "unixsock: Failed to connect to %s: %s",
 197                                 sa.sun_path, sdb_strerror(errno, errbuf, sizeof(errbuf)));
 198                 close(fd);
 199                 return -1;
 200         }
 201
 202         client->fh = fdopen(fd, "r+");
 203         if (! client->fh) {
 204                 char errbuf[1024];
 205                 sdb_log(SDB_LOG_ERR, "unixsock: Failed to open I/O "
 206                                 "stream for %s: %s", sa.sun_path,
 207                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 208                 close(fd);
 209                 return -1;
 210         }
 211
 212         /* enable line-buffering */
 213         setvbuf(client->fh, NULL, _IOLBF, 0);
 214
 215         client->shutdown = 0;
 216         return 0;
 217 } /* sdb_unixsock_client_connect */
 218
 219 int
 220 sdb_unixsock_client_send(sdb_unixsock_client_t *client,
 221                 const char *msg)
 222 {
 223         int status;
 224
 225         if ((! client) || (! client->fh))
 226                 return -1;
 227
 228         if (client->shutdown & SDB_SHUT_WR) /* reconnect */
 229                 sdb_unixsock_client_connect(client);
 230
 231         status = fprintf(client->fh, "%s\r\n", msg);
 232         if (status < 0) {
 233                 char errbuf[1024];
 234                 sdb_log(SDB_LOG_ERR, "unixsock: Failed to write to "
 235                                 "socket (%s): %s", client->path,
 236                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 237                 return status;
 238         }
 239         return status;
 240 } /* sdb_unixsock_client_send */
 241
 242 char *
 243 sdb_unixsock_client_recv(sdb_unixsock_client_t *client,
 244                 char *buffer, size_t buflen)
 245 {
 246         char *tmp;
 247
 248         if ((! client) || (! client->fh) || (! buffer))
 249                 return NULL;
 250
 251         if (client->shutdown & SDB_SHUT_RD) /* reconnect */
 252                 sdb_unixsock_client_connect(client);
 253
 254         tmp = NULL;
 255         while (tmp == NULL) {
 256                 errno = 0;
 257                 tmp = fgets(buffer, (int)buflen - 1, client->fh);
 258                 if (! tmp) {
 259                         if ((errno == EAGAIN) || (errno == EINTR))
 260                                 continue;
 261
 262                         if (! feof(client->fh)) {
 263                                 char errbuf[1024];
 264                                 sdb_log(SDB_LOG_ERR, "unixsock: Failed to read "
 265                                                 "from socket (%s): %s", client->path,
 266                                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 267                         }
 268                         return NULL;
 269                 }
 270         }
 271         buffer[buflen - 1] = '\0';
 272
 273         buflen = strlen(buffer);
 274         while (buflen && ((buffer[buflen - 1] == '\n') || (buffer[buflen - 1] == '\r'))) {
 275                 buffer[buflen - 1] = '\0';
 276                 --buflen;
 277         }
 278         return buffer;
 279 } /* sdb_unixsock_client_recv */
 280
 281 int
 282 sdb_unixsock_client_process_lines(sdb_unixsock_client_t *client,
 283                 sdb_unixsock_client_data_cb callback, sdb_object_t *user_data,
 284                 long int max_lines, const char *delim, int n_cols, ...)
 285 {
 286         int *types = NULL;
 287         int success = 0;
 288
 289         if ((! client) || (! client->fh) || (! callback))
 290                 return -1;
 291
 292         if (n_cols > 0) {
 293                 va_list ap;
 294                 int i;
 295
 296                 types = calloc((size_t)n_cols, sizeof(*types));
 297                 if (! types)
 298                         return -1;
 299
 300                 va_start(ap, n_cols);
 301
 302                 for (i = 0; i < n_cols; ++i) {
 303                         types[i] = va_arg(ap, int);
 304
 305                         if ((types[i] < 1) || (types[i] > SDB_TYPE_BINARY)) {
 306                                 sdb_log(SDB_LOG_ERR, "unixsock: Unknown column "
 307                                                 "type %i while processing response from the "
 308                                                 "UNIX socket @ %s.", types[i], client->path);
 309                                 va_end(ap);
 310                                 free(types);
 311                                 return -1;
 312                         }
 313                 }
 314
 315                 va_end(ap);
 316         }
 317
 318         while (42) {
 319                 char  buffer[1024];
 320                 char *line;
 321
 322                 int column_count;
 323
 324                 if (! max_lines)
 325                         break;
 326
 327                 if (max_lines > 0)
 328                         --max_lines;
 329
 330                 sdb_unixsock_client_clearerr(client);
 331                 line = sdb_unixsock_client_recv(client, buffer, sizeof(buffer));
 332
 333                 if (! line)
 334                         break;
 335
 336                 column_count = sdb_unixsock_get_column_count(line, delim);
 337
 338                 if ((n_cols >= 0) && (n_cols != column_count)) {
 339                         sdb_log(SDB_LOG_ERR, "unixsock: number of columns (%i) "
 340                                         "does not match the number of requested columns (%i) "
 341                                         "while processing response from the UNIX socket @ %s: %s",
 342                                         column_count, n_cols, client->path, line);
 343                         continue;
 344                 }
 345
 346                 if (column_count <= 0) /* no data */
 347                         continue;
 348
 349                 if (! sdb_unixsock_client_process_one_line(client, line, callback,
 350                                         user_data, delim, column_count, types))
 351                         ++success;
 352         }
 353
 354         free(types);
 355
 356         if ((max_lines > 0)
 357                         || ((max_lines < 0) && (! sdb_unixsock_client_eof(client)))
 358                         || sdb_unixsock_client_error(client)) {
 359                 char errbuf[1024];
 360                 sdb_log(SDB_LOG_ERR, "unixsock: Unexpected end of data while "
 361                                 "reading from socket (%s): %s", client->path,
 362                                 sdb_strerror(errno, errbuf, sizeof(errbuf)));
 363                 return -1;
 364         }
 365         if (! success)
 366                 return -1;
 367         return 0;
 368 } /* sdb_unixsock_client_process_lines */
 369
 370 int
 371 sdb_unixsock_client_shutdown(sdb_unixsock_client_t *client, int how)
 372 {
 373         int status;
 374
 375         if (! client) {
 376                 errno = ENOTSOCK;
 377                 return -1;
 378         }
 379
 380         fflush(client->fh);
 381         status = shutdown(fileno(client->fh), how);
 382
 383         if (! status) {
 384                 if (how == SHUT_RDWR)
 385                         client->shutdown |= SDB_SHUT_RDWR;
 386                 else
 387                         client->shutdown |= 1 << how;
 388         }
 389         return status;
 390 } /* sdb_unixsock_client_shutdown */
 391
 392 void
 393 sdb_unixsock_client_clearerr(sdb_unixsock_client_t *client)
 394 {
 395         if ((! client) || (! client->fh))
 396                 return;
 397         clearerr(client->fh);
 398 } /* sdb_unixsock_client_clearerr */
 399
 400 int
 401 sdb_unixsock_client_eof(sdb_unixsock_client_t *client)
 402 {
 403         if ((! client) || (! client->fh)) {
 404                 errno = EBADF;
 405                 return -1;
 406         }
 407         return feof(client->fh);
 408 } /* sdb_unixsock_client_eof */
 409
 410 int
 411 sdb_unixsock_client_error(sdb_unixsock_client_t *client)
 412 {
 413         if ((! client) || (! client->fh)) {
 414                 errno = EBADF;
 415                 return -1;
 416         }
 417         return ferror(client->fh);
 418 } /* sdb_unixsock_client_error */
 419
 420 void
 421 sdb_unixsock_client_destroy(sdb_unixsock_client_t *client)
 422 {
 423         if (! client)
 424                 return;
 425
 426         if (client->path)
 427                 free(client->path);
 428         client->path = NULL;
 429
 430         if (client->fh)
 431                 fclose(client->fh);
 432         client->fh = NULL;
 433
 434         free(client);
 435 } /* sdb_unixsock_client_destroy */
 436
 437 const char *
 438 sdb_unixsock_client_path(sdb_unixsock_client_t *client)
 439 {
 440         if (! client)
 441                 return NULL;
 442         return client->path;
 443 } /* sdb_unixsock_client_path */
 444
 445 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 446