log/logd.c

   1 /*
   2  * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License version 2.1
   6  * as published by the Free Software Foundation
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <stdio.h>
  15 #include <unistd.h>
  16 #include <syslog.h>
  17 #include <unistd.h>
  18
  19 #include <linux/types.h>
  20
  21 #include <libubox/uloop.h>
  22 #include <libubox/blobmsg.h>
  23 #include <libubox/list.h>
  24 #include <libubox/ustream.h>
  25 #include <libubus.h>
  26
  27 #include "syslog.h"
  28
  29 int debug = 0;
  30 static struct blob_buf b;
  31 static struct ubus_auto_conn conn;
  32 static LIST_HEAD(clients);
  33
  34 enum {
  35         READ_LINES,
  36         READ_STREAM,
  37         __READ_MAX
  38 };
  39
  40 static const struct blobmsg_policy read_policy[__READ_MAX] = {
  41         [READ_LINES] = { .name = "lines", .type = BLOBMSG_TYPE_INT32 },
  42         [READ_STREAM] = { .name = "stream", .type = BLOBMSG_TYPE_BOOL },
  43 };
  44
  45 static const struct blobmsg_policy write_policy =
  46         { .name = "event", .type = BLOBMSG_TYPE_STRING };
  47
  48 struct client {
  49         struct list_head list;
  50
  51         struct ustream_fd s;
  52         int fd;
  53 };
  54
  55 static void
  56 client_close(struct ustream *s)
  57 {
  58         struct client *cl = container_of(s, struct client, s.stream);
  59
  60         list_del(&cl->list);
  61         ustream_free(s);
  62         close(cl->fd);
  63         free(cl);
  64 }
  65
  66 static void client_notify_state(struct ustream *s)
  67 {
  68         client_close(s);
  69 }
  70
  71 static void
  72 log_fill_msg(struct blob_buf *b, struct log_head *l)
  73 {
  74         blob_buf_init(b, 0);
  75         blobmsg_add_string(b, "msg", l->data);
  76         blobmsg_add_u32(b, "id", l->id);
  77         blobmsg_add_u32(b, "priority", l->priority);
  78         blobmsg_add_u32(b, "source", l->source);
  79         blobmsg_add_u64(b, "time", l->ts.tv_sec * 1000LL);
  80 }
  81
  82 static int
  83 read_log(struct ubus_context *ctx, struct ubus_object *obj,
  84                 struct ubus_request_data *req, const char *method,
  85                 struct blob_attr *msg)
  86 {
  87         struct client *cl;
  88         struct blob_attr *tb[__READ_MAX];
  89         struct log_head *l;
  90         int count = 0;
  91         int fds[2];
  92         int ret;
  93         bool stream = true;
  94
  95         if (msg) {
  96                 blobmsg_parse(read_policy, __READ_MAX, tb, blob_data(msg), blob_len(msg));
  97                 if (tb[READ_LINES])
  98                         count = blobmsg_get_u32(tb[READ_LINES]);
  99                 if (tb[READ_STREAM])
 100                         stream = blobmsg_get_bool(tb[READ_STREAM]);
 101         }
 102         if (!stream)
 103                 count = 100;
 104
 105         if (pipe(fds) == -1) {
 106                 fprintf(stderr, "logd: failed to create pipe: %s\n", strerror(errno));
 107                 return -1;
 108         }
 109
 110         l = log_list(count, NULL);
 111         if (stream) {
 112                 ubus_request_set_fd(ctx, req, fds[0]);
 113                 cl = calloc(1, sizeof(*cl));
 114                 cl->s.stream.notify_state = client_notify_state;
 115                 cl->fd = fds[1];
 116                 ustream_fd_init(&cl->s, cl->fd);
 117                 list_add(&cl->list, &clients);
 118                 while ((!tb[READ_LINES] || count) && l) {
 119                         log_fill_msg(&b, l);
 120                         l = log_list(count, l);
 121                         ret = ustream_write(&cl->s.stream, (void *) b.head, blob_len(b.head) + sizeof(struct blob_attr), false);
 122                         if (ret < 0)
 123                                 break;
 124                 }
 125         } else {
 126                 while ((!tb[READ_LINES] || count) && l) {
 127                         log_fill_msg(&b, l);
 128                         ubus_send_reply(ctx, req, b.head);
 129                         l = log_list(count, l);
 130                 }
 131         }
 132         blob_buf_free(&b);
 133         return 0;
 134 }
 135
 136 static int
 137 write_log(struct ubus_context *ctx, struct ubus_object *obj,
 138                 struct ubus_request_data *req, const char *method,
 139                 struct blob_attr *msg)
 140 {
 141         struct blob_attr *tb;
 142         char *event;
 143
 144         if (msg) {
 145                 blobmsg_parse(&write_policy, 1, &tb, blob_data(msg), blob_len(msg));
 146                 if (tb) {
 147                         event = blobmsg_get_string(tb);
 148                         log_add(event, strlen(event) + 1, SOURCE_SYSLOG);
 149                 }
 150         }
 151
 152         return 0;
 153 }
 154
 155 static const struct ubus_method log_methods[] = {
 156         UBUS_METHOD("read", read_log, read_policy),
 157         { .name = "write", .handler = write_log, .policy = &write_policy, .n_policy = 1 },
 158 };
 159
 160 static struct ubus_object_type log_object_type =
 161         UBUS_OBJECT_TYPE("log", log_methods);
 162
 163 static struct ubus_object log_object = {
 164         .name = "log",
 165         .type = &log_object_type,
 166         .methods = log_methods,
 167         .n_methods = ARRAY_SIZE(log_methods),
 168 };
 169
 170 void
 171 ubus_notify_log(struct log_head *l)
 172 {
 173         struct client *c;
 174
 175         if (list_empty(&clients))
 176                 return;
 177
 178         blob_buf_init(&b, 0);
 179         blobmsg_add_string(&b, "msg", l->data);
 180         blobmsg_add_u32(&b, "id", l->id);
 181         blobmsg_add_u32(&b, "priority", l->priority);
 182         blobmsg_add_u32(&b, "source", l->source);
 183         blobmsg_add_u64(&b, "time", (((__u64) l->ts.tv_sec) * 1000) + (l->ts.tv_nsec / 1000000));
 184
 185         list_for_each_entry(c, &clients, list)
 186                 ustream_write(&c->s.stream, (void *) b.head, blob_len(b.head) + sizeof(struct blob_attr), false);
 187
 188         blob_buf_free(&b);
 189 }
 190
 191 static void
 192 ubus_connect_handler(struct ubus_context *ctx)
 193 {
 194         int ret;
 195
 196         ret = ubus_add_object(ctx, &log_object);
 197         if (ret) {
 198                 fprintf(stderr, "Failed to add object: %s\n", ubus_strerror(ret));
 199                 exit(1);
 200         }
 201         fprintf(stderr, "log: connected to ubus\n");
 202 }
 203
 204 int
 205 main(int argc, char **argv)
 206 {
 207         int ch, log_size = 16;
 208
 209         signal(SIGPIPE, SIG_IGN);
 210         while ((ch = getopt(argc, argv, "S:")) != -1) {
 211                 switch (ch) {
 212                 case 'S':
 213                         log_size = atoi(optarg);
 214                         if (log_size < 1)
 215                                 log_size = 16;
 216                         break;
 217                 }
 218         }
 219         log_size *= 1024;
 220
 221         uloop_init();
 222         log_init(log_size);
 223         conn.cb = ubus_connect_handler;
 224         ubus_auto_connect(&conn);
 225         uloop_run();
 226         log_shutdown();
 227         uloop_done();
 228
 229         return 0;
 230 }