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
  18 #include <linux/types.h>
  19
  20 #include <libubox/uloop.h>
  21 #include <libubox/blobmsg.h>
  22 #include <libubox/list.h>
  23 #include <libubox/ustream.h>
  24 #include <libubus.h>
  25
  26 #include "syslog.h"
  27
  28 int debug = 0;
  29 static struct blob_buf b;
  30 static struct ubus_auto_conn conn;
  31 static LIST_HEAD(clients);
  32
  33 static const struct blobmsg_policy read_policy =
  34         { .name = "lines", .type = BLOBMSG_TYPE_INT32 };
  35
  36 static const struct blobmsg_policy write_policy =
  37         { .name = "event", .type = BLOBMSG_TYPE_STRING };
  38
  39 struct client {
  40         struct list_head list;
  41
  42         struct ustream_fd s;
  43         int fd;
  44 };
  45
  46 static void
  47 client_close(struct ustream *s)
  48 {
  49         struct client *cl = container_of(s, struct client, s.stream);
  50
  51         list_del(&cl->list);
  52         ustream_free(s);
  53         close(cl->fd);
  54         free(cl);
  55 }
  56
  57 static void
  58 client_notify_write(struct ustream *s, int bytes)
  59 {
  60         if (s->w.data_bytes < 128 && ustream_read_blocked(s))
  61                 ustream_set_read_blocked(s, false);
  62 }
  63
  64 static void client_notify_state(struct ustream *s)
  65 {
  66         if (!s->eof)
  67                 return;
  68
  69         if (!s->w.data_bytes)
  70                 return client_close(s);
  71 }
  72
  73 static int
  74 read_log(struct ubus_context *ctx, struct ubus_object *obj,
  75                 struct ubus_request_data *req, const char *method,
  76                 struct blob_attr *msg)
  77 {
  78         struct client *cl;
  79         struct blob_attr *tb;
  80         struct log_head *l;
  81         int count = 0;
  82         int fds[2];
  83
  84         if (msg) {
  85                 blobmsg_parse(&read_policy, 1, &tb, blob_data(msg), blob_len(msg));
  86                 if (tb)
  87                         count = blobmsg_get_u32(tb);
  88         }
  89
  90         pipe(fds);
  91         ubus_request_set_fd(ctx, req, fds[0]);
  92
  93         cl = calloc(1, sizeof(*cl));
  94         cl->s.stream.notify_write = client_notify_write;
  95         cl->s.stream.notify_state = client_notify_state;
  96         cl->fd = fds[1];
  97         ustream_fd_init(&cl->s, cl->fd);
  98         list_add(&cl->list, &clients);
  99         l = log_list(count, NULL);
 100         while ((!tb || count) && l) {
 101                 blob_buf_init(&b, 0);
 102                 blobmsg_add_string(&b, "msg", l->data);
 103                 blobmsg_add_u32(&b, "id", l->id);
 104                 blobmsg_add_u32(&b, "priority", l->priority);
 105                 blobmsg_add_u32(&b, "source", l->source);
 106                 blobmsg_add_u64(&b, "time", l->ts.tv_sec);
 107                 l = log_list(count, l);
 108                 if (ustream_write(&cl->s.stream, (void *) b.head, blob_len(b.head) + sizeof(struct blob_attr), false) <= 0)
 109                         break;
 110         }
 111         return 0;
 112 }
 113
 114 static int
 115 write_log(struct ubus_context *ctx, struct ubus_object *obj,
 116                 struct ubus_request_data *req, const char *method,
 117                 struct blob_attr *msg)
 118 {
 119         struct blob_attr *tb;
 120         char *event;
 121
 122         if (msg) {
 123                 blobmsg_parse(&write_policy, 1, &tb, blob_data(msg), blob_len(msg));
 124                 if (tb) {
 125                         event = blobmsg_get_string(tb);
 126                         log_add(event, strlen(event) + 1, SOURCE_SYSLOG);
 127                 }
 128         }
 129
 130         return 0;
 131 }
 132
 133 static const struct ubus_method log_methods[] = {
 134         { .name = "read", .handler = read_log, .policy = &read_policy, .n_policy = 1 },
 135         { .name = "write", .handler = write_log, .policy = &write_policy, .n_policy = 1 },
 136 };
 137
 138 static struct ubus_object_type log_object_type =
 139         UBUS_OBJECT_TYPE("log", log_methods);
 140
 141 static struct ubus_object log_object = {
 142         .name = "log",
 143         .type = &log_object_type,
 144         .methods = log_methods,
 145         .n_methods = ARRAY_SIZE(log_methods),
 146 };
 147
 148 void
 149 ubus_notify_log(struct log_head *l)
 150 {
 151         struct client *c;
 152
 153         if (list_empty(&clients))
 154                 return;
 155
 156         list_for_each_entry(c, &clients, list) {
 157                 blob_buf_init(&b, 0);
 158                 blobmsg_add_string(&b, "msg", l->data);
 159                 blobmsg_add_u32(&b, "id", l->id);
 160                 blobmsg_add_u32(&b, "priority", l->priority);
 161                 blobmsg_add_u32(&b, "source", l->source);
 162                 blobmsg_add_u64(&b, "time", (((__u64) l->ts.tv_sec) * 1000) + (l->ts.tv_nsec / 1000000));
 163                 ustream_write(&c->s.stream, (void *) b.head, blob_len(b.head) + sizeof(struct blob_attr), false);
 164         }
 165 }
 166
 167 static void
 168 ubus_connect_handler(struct ubus_context *ctx)
 169 {
 170         int ret;
 171
 172         ret = ubus_add_object(ctx, &log_object);
 173         if (ret)
 174                 fprintf(stderr, "Failed to add object: %s\n", ubus_strerror(ret));
 175         fprintf(stderr, "log: connected to ubus\n");
 176 }
 177
 178 int
 179 main(int argc, char **argv)
 180 {
 181         signal(SIGPIPE, SIG_IGN);
 182
 183         uloop_init();
 184         log_init();
 185         conn.cb = ubus_connect_handler;
 186         ubus_auto_connect(&conn);
 187         uloop_run();
 188         log_shutdown();
 189         uloop_done();
 190
 191         return 0;
 192 }