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);
  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         if (strlen(remain[2]) == 0) {
 109                 printf_verbose("Connecting to hostname : %s, port : %d, "
 110                                 "proto : IPv%d\n",
 111                                 ctx->relay_hostname, ctx->port, proto);
 112                 ret = 0;
 113                 goto end;
 114         }
 115         ret = sscanf(remain[2], "host/%[a-zA-Z.0-9%-]/%s",
 116                         ctx->traced_hostname, ctx->session_name);
 117         if (ret != 2) {
 118                 fprintf(stderr, "[error] Format : "
 119                         "net://<hostname>/host/<traced_hostname>/<session_name>\n");
 120                 goto end;
 121         }
 122
 123         printf_verbose("Connecting to hostname : %s, port : %d, "
 124                         "traced hostname : %s, session name : %s, "
 125                         "proto : IPv%d\n",
 126                         ctx->relay_hostname, ctx->port, ctx->traced_hostname,
 127                         ctx->session_name, proto);
 128         ret = 0;
 129
 130 end:
 131         return ret;
 132 }
 133
 134 static int lttng_live_open_trace_read(const char *path)
 135 {
 136         int ret = 0;
 137         struct lttng_live_ctx *ctx;
 138
 139         ctx = g_new0(struct lttng_live_ctx, 1);
 140         ctx->session = g_new0(struct lttng_live_session, 1);
 141
 142         /* We need a pointer to the context from the packet_seek function. */
 143         ctx->session->ctx = ctx;
 144
 145         /* HT to store the CTF traces. */
 146         ctx->session->ctf_traces = g_hash_table_new(g_direct_hash,
 147                         g_direct_equal);
 148         ctx->port = -1;
 149         ctx->session_ids = g_array_new(FALSE, TRUE, sizeof(uint64_t));
 150
 151         ret = parse_url(path, ctx);
 152         if (ret < 0) {
 153                 goto end_free;
 154         }
 155
 156         ret = lttng_live_connect_viewer(ctx);
 157         if (ret < 0) {
 158                 fprintf(stderr, "[error] Connection failed\n");
 159                 goto end_free;
 160         }
 161         printf_verbose("LTTng-live connected to relayd\n");
 162
 163         ret = lttng_live_establish_connection(ctx);
 164         if (ret < 0) {
 165                 goto end_free;
 166         }
 167
 168         printf_verbose("Listing sessions\n");
 169         ret = lttng_live_list_sessions(ctx, path);
 170         if (ret < 0) {
 171                 fprintf(stderr, "[error] List error\n");
 172                 goto end_free;
 173         }
 174
 175         if (ctx->session_ids->len > 0)
 176                 lttng_live_read(ctx);
 177
 178 end_free:
 179         g_hash_table_destroy(ctx->session->ctf_traces);
 180         g_free(ctx->session);
 181         g_free(ctx->session->streams);
 182         g_free(ctx);
 183         return ret;
 184 }
 185
 186 static
 187 struct bt_trace_descriptor *lttng_live_open_trace(const char *path, int flags,
 188                 void (*packet_seek)(struct bt_stream_pos *pos, size_t index,
 189                         int whence), FILE *metadata_fp)
 190 {
 191         struct ctf_text_stream_pos *pos;
 192
 193         switch (flags & O_ACCMODE) {
 194         case O_RDONLY:
 195                 /* OK */
 196                 break;
 197         case O_RDWR:
 198                 fprintf(stderr, "[error] lttng live plugin cannot be used as output plugin.\n");
 199                 goto error;
 200         default:
 201                 fprintf(stderr, "[error] Incorrect open flags.\n");
 202                 goto error;
 203         }
 204
 205         pos = g_new0(struct ctf_text_stream_pos, 1);
 206         pos->parent.rw_table = NULL;
 207         pos->parent.event_cb = NULL;
 208         pos->parent.trace = &pos->trace_descriptor;
 209         lttng_live_open_trace_read(path);
 210         return &pos->trace_descriptor;
 211
 212 error:
 213         return NULL;
 214 }
 215
 216 static
 217 int lttng_live_close_trace(struct bt_trace_descriptor *td)
 218 {
 219         struct ctf_text_stream_pos *pos =
 220                 container_of(td, struct ctf_text_stream_pos,
 221                         trace_descriptor);
 222         free(pos);
 223         return 0;
 224 }
 225
 226 static
 227 struct bt_format lttng_live_format = {
 228         .open_trace = lttng_live_open_trace,
 229         .close_trace = lttng_live_close_trace,
 230 };
 231
 232 static
 233 void __attribute__((constructor)) lttng_live_init(void)
 234 {
 235         int ret;
 236
 237         lttng_live_format.name = g_quark_from_static_string("lttng-live");
 238         ret = bt_register_format(&lttng_live_format);
 239         assert(!ret);
 240 }
 241
 242 static
 243 void __attribute__((destructor)) lttng_live_exit(void)
 244 {
 245         bt_unregister_format(&lttng_live_format);
 246 }