logread.c

   1 /*
   2  * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
   3  * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU Lesser General Public License version 2.1
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <sys/types.h>
  16 #include <sys/stat.h>
  17
  18 #include <fcntl.h>
  19 #include <time.h>
  20 #include <stdio.h>
  21 #include <unistd.h>
  22 #include <sys/types.h>
  23 #include <sys/socket.h>
  24
  25 #define SYSLOG_NAMES
  26 #include <syslog.h>
  27
  28 #include <libubox/blobmsg_json.h>
  29 #include <libubox/usock.h>
  30 #include <libubox/uloop.h>
  31 #include "libubus.h"
  32
  33 enum {
  34         LOG_STDOUT,
  35         LOG_FILE,
  36         LOG_NET,
  37 };
  38
  39 enum {
  40         LOG_MSG,
  41         LOG_ID,
  42         LOG_PRIO,
  43         LOG_SOURCE,
  44         LOG_TIME,
  45         __LOG_MAX
  46 };
  47
  48 static const struct blobmsg_policy log_policy[] = {
  49         [LOG_MSG] = { .name = "msg", .type = BLOBMSG_TYPE_STRING },
  50         [LOG_ID] = { .name = "id", .type = BLOBMSG_TYPE_INT32 },
  51         [LOG_PRIO] = { .name = "priority", .type = BLOBMSG_TYPE_INT32 },
  52         [LOG_SOURCE] = { .name = "source", .type = BLOBMSG_TYPE_INT32 },
  53         [LOG_TIME] = { .name = "time", .type = BLOBMSG_TYPE_INT64 },
  54 };
  55
  56 static struct ubus_subscriber log_event;
  57 static struct uloop_timeout retry;
  58 static struct uloop_fd sender;
  59 static const char *log_file, *log_ip, *log_port, *log_prefix, *pid_file;
  60 static int log_type = LOG_STDOUT;
  61 static int log_size, log_udp;
  62
  63 static const char* getcodetext(int value, CODE *codetable) {
  64         CODE *i;
  65
  66         if (value >= 0)
  67                 for (i = codetable; i->c_val != -1; i++)
  68                         if (i->c_val == value)
  69                                 return (i->c_name);
  70         return "<unknown>";
  71 };
  72
  73 static void log_handle_reconnect(struct uloop_timeout *timeout)
  74 {
  75         sender.fd = usock((log_udp) ? (USOCK_UDP) : (USOCK_TCP), log_ip, log_port);
  76         if (sender.fd < 0) {
  77                 fprintf(stderr, "failed to connect: %s\n", strerror(errno));
  78                 uloop_timeout_set(&retry, 1000);
  79         } else {
  80                 uloop_fd_add(&sender, ULOOP_READ);
  81                 syslog(0, "Logread connected to %s:%s\n", log_ip, log_port);
  82         }
  83 }
  84
  85 static void log_handle_remove(struct ubus_context *ctx, struct ubus_subscriber *s,
  86                         uint32_t id)
  87 {
  88         fprintf(stderr, "Object %08x went away\n", id);
  89 }
  90
  91 static void log_handle_fd(struct uloop_fd *u, unsigned int events)
  92 {
  93         if (u->eof) {
  94                 uloop_fd_delete(u);
  95                 close(sender.fd);
  96                 sender.fd = -1;
  97                 uloop_timeout_set(&retry, 1000);
  98         }
  99 }
 100
 101 static int log_notify(struct ubus_context *ctx, struct ubus_object *obj,
 102                         struct ubus_request_data *req, const char *method,
 103                         struct blob_attr *msg)
 104 {
 105         struct blob_attr *tb[__LOG_MAX];
 106         struct stat s;
 107         char buf[512];
 108         uint32_t p;
 109         char *str;
 110         time_t t;
 111         char *c;
 112
 113         if (sender.fd < 0)
 114                 return 0;
 115
 116         blobmsg_parse(log_policy, ARRAY_SIZE(log_policy), tb, blob_data(msg), blob_len(msg));
 117         if (!tb[LOG_ID] || !tb[LOG_PRIO] || !tb[LOG_SOURCE] || !tb[LOG_TIME])
 118                 return 1;
 119
 120         if ((log_type == LOG_FILE) && log_size && (!stat(log_file, &s)) && (s.st_size > log_size)) {
 121                 char *old = malloc(strlen(log_file) + 5);
 122
 123                 close(sender.fd);
 124                 if (old) {
 125                         sprintf(old, "%s.old", log_file);
 126                         rename(log_file, old);
 127                         free(old);
 128                 }
 129                 sender.fd = open(log_file, O_CREAT | O_WRONLY | O_APPEND, 0600);
 130                 if (sender.fd < 0) {
 131 //                      fprintf(stderr, "failed to open %s: %s\n", log_file, strerror(errno));
 132                         exit(-1);
 133                 }
 134         }
 135
 136         t = blobmsg_get_u64(tb[LOG_TIME]) / 1000;
 137         c = ctime(&t);
 138         p = blobmsg_get_u32(tb[LOG_PRIO]);
 139         c[strlen(c) - 1] = '\0';
 140         str = blobmsg_format_json(msg, true);
 141         if (log_type == LOG_NET) {
 142                 int err;
 143                 int len;
 144
 145                 *buf = '\0';
 146                 if (log_prefix)
 147                         snprintf(buf, sizeof(buf), "%s: ", log_prefix);
 148
 149                 len = strlen(buf);
 150
 151                 snprintf(&buf[len], sizeof(buf) - len, "%s%s\n",
 152                         (blobmsg_get_u32(tb[LOG_SOURCE])) ? ("") : ("kernel: "),
 153                         method);
 154                 if (log_udp)
 155                         err = write(sender.fd, buf, strlen(buf));
 156                 else
 157                         err = send(sender.fd, buf, strlen(buf), 0);
 158
 159                 if (err < 0) {
 160                         syslog(0, "failed to send log data to %s:%s via %s\n",
 161                                 log_ip, log_port, (log_udp) ? ("udp") : ("tcp"));
 162                         uloop_fd_delete(&sender);
 163                         close(sender.fd);
 164                         sender.fd = -1;
 165                         uloop_timeout_set(&retry, 1000);
 166                 }
 167         } else {
 168                 snprintf(buf, sizeof(buf), "%s %s.%s%s %s\n",
 169                         c, getcodetext(LOG_FAC(p) << 3, facilitynames), getcodetext(LOG_PRI(p), prioritynames),
 170                         (blobmsg_get_u32(tb[LOG_SOURCE])) ? ("") : (" kernel:"),
 171                         method);
 172                 write(sender.fd, buf, strlen(buf));
 173         }
 174
 175         free(str);
 176         if (log_type == LOG_FILE)
 177                 fsync(sender.fd);
 178
 179         return 0;
 180 }
 181
 182 static void follow_log(struct ubus_context *ctx, int id)
 183 {
 184         FILE *fp;
 185         int ret;
 186
 187         signal(SIGPIPE, SIG_IGN);
 188
 189         if (pid_file) {
 190                 fp = fopen(pid_file, "w+");
 191                 if (fp) {
 192                         fprintf(fp, "%d", getpid());
 193                         fclose(fp);
 194                 }
 195         }
 196
 197         uloop_init();
 198         ubus_add_uloop(ctx);
 199
 200         log_event.remove_cb = log_handle_remove;
 201         log_event.cb = log_notify;
 202         ret = ubus_register_subscriber(ctx, &log_event);
 203         if (ret)
 204                 fprintf(stderr, "Failed to add watch handler: %s\n", ubus_strerror(ret));
 205
 206         ret = ubus_subscribe(ctx, &log_event, id);
 207         if (ret)
 208                 fprintf(stderr, "Failed to add watch handler: %s\n", ubus_strerror(ret));
 209
 210         if (log_ip && log_port) {
 211                 openlog("logread", LOG_PID, LOG_DAEMON);
 212                 log_type = LOG_NET;
 213                 sender.cb = log_handle_fd;
 214                 retry.cb = log_handle_reconnect;
 215                 uloop_timeout_set(&retry, 1000);
 216         } else if (log_file) {
 217                 log_type = LOG_FILE;
 218                 sender.fd = open(log_file, O_CREAT | O_WRONLY| O_APPEND, 0600);
 219                 if (sender.fd < 0) {
 220                         fprintf(stderr, "failed to open %s: %s\n", log_file, strerror(errno));
 221                         exit(-1);
 222                 }
 223         } else {
 224                 sender.fd = STDOUT_FILENO;
 225         }
 226
 227         uloop_run();
 228         ubus_free(ctx);
 229         uloop_done();
 230 }
 231
 232 enum {
 233         READ_LINE,
 234         __READ_MAX
 235 };
 236
 237
 238
 239 static const struct blobmsg_policy read_policy[] = {
 240         [READ_LINE] = { .name = "lines", .type = BLOBMSG_TYPE_ARRAY },
 241 };
 242
 243 static void read_cb(struct ubus_request *req, int type, struct blob_attr *msg)
 244 {
 245         struct blob_attr *cur;
 246         struct blob_attr *_tb[__READ_MAX];
 247         time_t t;
 248         int rem;
 249
 250         if (!msg)
 251                 return;
 252
 253         blobmsg_parse(read_policy, ARRAY_SIZE(read_policy), _tb, blob_data(msg), blob_len(msg));
 254         if (!_tb[READ_LINE])
 255                 return;
 256         blobmsg_for_each_attr(cur, _tb[READ_LINE], rem) {
 257                 struct blob_attr *tb[__LOG_MAX];
 258                 uint32_t p;
 259                 char *c;
 260
 261                 if (blobmsg_type(cur) != BLOBMSG_TYPE_TABLE)
 262                         continue;
 263
 264                 blobmsg_parse(log_policy, ARRAY_SIZE(log_policy), tb, blobmsg_data(cur), blobmsg_data_len(cur));
 265                 if (!tb[LOG_MSG] || !tb[LOG_ID] || !tb[LOG_PRIO] || !tb[LOG_SOURCE] || !tb[LOG_TIME])
 266                         continue;
 267
 268                 t = blobmsg_get_u64(tb[LOG_TIME]);
 269                 p = blobmsg_get_u32(tb[LOG_PRIO]);
 270                 c = ctime(&t);
 271                 c[strlen(c) - 1] = '\0';
 272
 273                 printf("%s %s.%s%s %s\n",
 274                         c, getcodetext(LOG_FAC(p) << 3, facilitynames), getcodetext(LOG_PRI(p), prioritynames),
 275                         (blobmsg_get_u32(tb[LOG_SOURCE])) ? ("") : (" kernel:"),
 276                         blobmsg_get_string(tb[LOG_MSG]));
 277         }
 278 }
 279
 280 static int usage(const char *prog)
 281 {
 282         fprintf(stderr, "Usage: %s [options]\n"
 283                 "Options:\n"
 284                 "    -s <path>          Path to ubus socket\n"
 285                 "    -l <count>         Got only the last 'count' messages\n"
 286                 "    -r <server> <port> Stream message to a server\n"
 287                 "    -F <file>          Log file\n"
 288                 "    -S <bytes>         Log size\n"
 289                 "    -p <file>          PID file\n"
 290                 "    -P <prefix>        Prefix custom text to streamed messages\n"
 291                 "    -f                 Follow log messages\n"
 292                 "    -u                 Use UDP as the protocol\n"
 293                 "\n", prog);
 294         return 1;
 295 }
 296
 297 int main(int argc, char **argv)
 298 {
 299         struct ubus_context *ctx;
 300         uint32_t id;
 301         const char *ubus_socket = NULL;
 302         int ch, ret, subscribe = 0, lines = 0;
 303         static struct blob_buf b;
 304
 305         while ((ch = getopt(argc, argv, "ufcs:l:r:F:p:S:P:")) != -1) {
 306                 switch (ch) {
 307                 case 'u':
 308                         log_udp = 1;
 309                         break;
 310                 case 's':
 311                         ubus_socket = optarg;
 312                         break;
 313                 case 'r':
 314                         log_ip = optarg++;
 315                         log_port = argv[optind++];
 316                         break;
 317                 case 'F':
 318                         log_file = optarg;
 319                         break;
 320                 case 'p':
 321                         pid_file = optarg;
 322                         break;
 323                 case 'P':
 324                         log_prefix = optarg;
 325                         break;
 326                 case 'f':
 327                         subscribe = 1;
 328                         break;
 329                 case 'l':
 330                         lines = atoi(optarg);
 331                         break;
 332                 case 'S':
 333                         log_size = atoi(optarg);
 334                         if (log_size < 1)
 335                                 log_size = 1;
 336                         log_size *= 1024;
 337                         break;
 338                 default:
 339                         return usage(*argv);
 340                 }
 341         }
 342
 343         ctx = ubus_connect(ubus_socket);
 344         if (!ctx) {
 345                 fprintf(stderr, "Failed to connect to ubus\n");
 346                 return -1;
 347         }
 348
 349         ret = ubus_lookup_id(ctx, "log", &id);
 350         if (ret)
 351                 fprintf(stderr, "Failed to find log object: %s\n", ubus_strerror(ret));
 352
 353         if (!subscribe || lines) {
 354                 blob_buf_init(&b, 0);
 355                 if (lines)
 356                         blobmsg_add_u32(&b, "lines", lines);
 357                 ubus_invoke(ctx, id, "read", b.head, read_cb, 0, 3000);
 358         }
 359
 360         if (subscribe)
 361                 follow_log(ctx, id);
 362
 363         return 0;
 364 }