formats/lttng-live/lttng-live-plugin.c

   1 /*
   2  * BabelTrace - LTTng live Output
   3  *
   4  * Copyright 2013 Julien Desfossez <jdesfossez@efficios.com>
   5  *                Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  20  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  23  * SOFTWARE.
  24  */
  25
  26 #include <babeltrace/ctf-text/types.h>
  27 #include <babeltrace/format.h>
  28 #include <babeltrace/babeltrace-internal.h>
  29 #include <inttypes.h>
  30 #include <sys/mman.h>
  31 #include <errno.h>
  32 #include <sys/types.h>
  33 #include <sys/stat.h>
  34 #include <fcntl.h>
  35 #include <dirent.h>
  36 #include <glib.h>
  37 #include <unistd.h>
  38 #include <stdlib.h>
  39 #include "lttng-live.h"
  40
  41 /*
  42  * hostname parameter needs to hold NAME_MAX chars.
  43  */
  44 static
  45 int parse_url(const char *path, struct lttng_live_ctx *ctx)
  46 {
  47         char remain[3][NAME_MAX];
  48         int ret = -1, proto, proto_offset = 0;
  49         size_t path_len = strlen(path); /* not accounting \0 */
  50
  51         /*
  52          * Since sscanf API does not allow easily checking string length
  53          * against a size defined by a macro. Test it beforehand on the
  54          * input. We know the output is always <= than the input length.
  55          */
  56         if (path_len >= NAME_MAX) {
  57                 goto end;
  58         }
  59         ret = sscanf(path, "net%d://", &proto);
  60         if (ret < 1) {
  61                 proto = 4;
  62                 /* net:// */
  63                 proto_offset = strlen("net://");
  64         } else {
  65                 /* net4:// or net6:// */
  66                 proto_offset = strlen("netX://");
  67         }
  68         if (proto_offset > path_len) {
  69                 goto end;
  70         }
  71         /* TODO : parse for IPv6 as well */
  72         /* Parse the hostname or IP */
  73         ret = sscanf(&path[proto_offset], "%[a-zA-Z.0-9%-]%s",
  74                 ctx->relay_hostname, remain[0]);
  75         if (ret == 2) {
  76                 /* Optional port number */
  77                 switch (remain[0][0]) {
  78                 case ':':
  79                         ret = sscanf(remain[0], ":%d%s", &ctx->port, remain[1]);
  80                         /* Optional session ID with port number */
  81                         if (ret == 2) {
  82                                 ret = sscanf(remain[1], "/%s", remain[2]);
  83                                 /* Accept 0 or 1 (optional) */
  84                                 if (ret < 0) {
  85                                         goto end;
  86                                 }
  87                         }
  88                         break;
  89                 case '/':
  90                         /* Optional session ID */
  91                         ret = sscanf(remain[0], "/%s", remain[2]);
  92                         /* Accept 0 or 1 (optional) */
  93                         if (ret < 0) {
  94                                 goto end;
  95                         }
  96                         break;
  97                 default:
  98                         fprintf(stderr, "[error] wrong delimitor : %c\n",
  99                                 remain[0][0]);
 100                         ret = -1;
 101                         goto end;
 102                 }
 103         }
 104
 105         if (ctx->port < 0) {
 106                 ctx->port = LTTNG_DEFAULT_NETWORK_VIEWER_PORT;
 107         }
 108
 109         if (strlen(remain[2]) == 0) {
 110                 printf_verbose("Connecting to hostname : %s, port : %d, "
 111                                 "proto : IPv%d\n",
 112                                 ctx->relay_hostname, ctx->port, proto);
 113                 ret = 0;
 114                 goto end;
 115         }
 116         ret = sscanf(remain[2], "host/%[a-zA-Z.0-9%-]/%s",
 117                         ctx->traced_hostname, ctx->session_name);
 118         if (ret != 2) {
 119                 fprintf(stderr, "[error] Format : "
 120                         "net://<hostname>/host/<traced_hostname>/<session_name>\n");
 121                 goto end;
 122         }
 123
 124         printf_verbose("Connecting to hostname : %s, port : %d, "
 125                         "traced hostname : %s, session name : %s, "
 126                         "proto : IPv%d\n",
 127                         ctx->relay_hostname, ctx->port, ctx->traced_hostname,
 128                         ctx->session_name, proto);
 129         ret = 0;
 130
 131 end:
 132         return ret;
 133 }
 134
 135 static int lttng_live_open_trace_read(const char *path)
 136 {
 137         int ret = 0;
 138         struct lttng_live_ctx *ctx;
 139
 140         ctx = g_new0(struct lttng_live_ctx, 1);
 141         ctx->session = g_new0(struct lttng_live_session, 1);
 142
 143         /* We need a pointer to the context from the packet_seek function. */
 144         ctx->session->ctx = ctx;
 145
 146         /* HT to store the CTF traces. */
 147         ctx->session->ctf_traces = g_hash_table_new(g_direct_hash,
 148                         g_direct_equal);
 149         ctx->port = -1;
 150         ctx->session_ids = g_array_new(FALSE, TRUE, sizeof(uint64_t));
 151
 152         ret = parse_url(path, ctx);
 153         if (ret < 0) {
 154                 goto end_free;
 155         }
 156
 157         ret = lttng_live_connect_viewer(ctx);
 158         if (ret < 0) {
 159                 fprintf(stderr, "[error] Connection failed\n");
 160                 goto end_free;
 161         }
 162         printf_verbose("LTTng-live connected to relayd\n");
 163
 164         ret = lttng_live_establish_connection(ctx);
 165         if (ret < 0) {
 166                 goto end_free;
 167         }
 168
 169         printf_verbose("Listing sessions\n");
 170         ret = lttng_live_list_sessions(ctx, path);
 171         if (ret < 0) {
 172                 fprintf(stderr, "[error] List error\n");
 173                 goto end_free;
 174         }
 175
 176         if (ctx->session_ids->len > 0) {
 177                 lttng_live_read(ctx);
 178         }
 179
 180 end_free:
 181         g_hash_table_destroy(ctx->session->ctf_traces);
 182         g_free(ctx->session);
 183         g_free(ctx->session->streams);
 184         g_free(ctx);
 185         return ret;
 186 }
 187
 188 static
 189 struct bt_trace_descriptor *lttng_live_open_trace(const char *path, int flags,
 190                 void (*packet_seek)(struct bt_stream_pos *pos, size_t index,
 191                         int whence), FILE *metadata_fp)
 192 {
 193         struct ctf_text_stream_pos *pos;
 194
 195         switch (flags & O_ACCMODE) {
 196         case O_RDONLY:
 197                 /* OK */
 198                 break;
 199         case O_RDWR:
 200                 fprintf(stderr, "[error] lttng live plugin cannot be used as output plugin.\n");
 201                 goto error;
 202         default:
 203                 fprintf(stderr, "[error] Incorrect open flags.\n");
 204                 goto error;
 205         }
 206
 207         pos = g_new0(struct ctf_text_stream_pos, 1);
 208         pos->parent.rw_table = NULL;
 209         pos->parent.event_cb = NULL;
 210         pos->parent.trace = &pos->trace_descriptor;
 211         lttng_live_open_trace_read(path);
 212         return &pos->trace_descriptor;
 213
 214 error:
 215         return NULL;
 216 }
 217
 218 static
 219 int lttng_live_close_trace(struct bt_trace_descriptor *td)
 220 {
 221         struct ctf_text_stream_pos *pos =
 222                 container_of(td, struct ctf_text_stream_pos,
 223                         trace_descriptor);
 224         free(pos);
 225         return 0;
 226 }
 227
 228 static
 229 struct bt_format lttng_live_format = {
 230         .open_trace = lttng_live_open_trace,
 231         .close_trace = lttng_live_close_trace,
 232 };
 233
 234 static
 235 void __attribute__((constructor)) lttng_live_init(void)
 236 {
 237         int ret;
 238
 239         lttng_live_format.name = g_quark_from_static_string("lttng-live");
 240         ret = bt_register_format(&lttng_live_format);
 241         assert(!ret);
 242 }
 243
 244 static
 245 void __attribute__((destructor)) lttng_live_exit(void)
 246 {
 247         bt_unregister_format(&lttng_live_format);
 248 }