ctfser/ctfser.c

   1 /*
   2  * Copyright 2019 Philippe Proulx <pproulx@efficios.com>
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a copy
   5  * of this software and associated documentation files (the "Software"), to deal
   6  * in the Software without restriction, including without limitation the rights
   7  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   8  * copies of the Software, and to permit persons to whom the Software is
   9  * furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  17  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  19  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  20  * SOFTWARE.
  21  */
  22
  23 #define BT_LOG_TAG "CTFSER"
  24 #include "logging.h"
  25
  26 #include <unistd.h>
  27 #include <string.h>
  28 #include <inttypes.h>
  29 #include <sys/types.h>
  30 #include <sys/stat.h>
  31 #include <unistd.h>
  32 #include <babeltrace/assert-internal.h>
  33 #include <stdarg.h>
  34 #include <ctype.h>
  35 #include <glib.h>
  36 #include <stdlib.h>
  37 #include <stdio.h>
  38 #include <wchar.h>
  39 #include <stdbool.h>
  40 #include <babeltrace/babeltrace-internal.h>
  41 #include <babeltrace/common-internal.h>
  42 #include <babeltrace/ctfser-internal.h>
  43 #include <babeltrace/compat/unistd-internal.h>
  44 #include <babeltrace/compat/fcntl-internal.h>
  45
  46 static inline
  47 uint64_t get_packet_size_increment_bytes(void)
  48 {
  49         return bt_common_get_page_size() * 8;
  50 }
  51
  52 static inline
  53 void mmap_align_ctfser(struct bt_ctfser *ctfser)
  54 {
  55         ctfser->base_mma = mmap_align(ctfser->cur_packet_size_bytes, PROT_WRITE,
  56                 MAP_SHARED, ctfser->fd, ctfser->mmap_offset);
  57 }
  58
  59 BT_HIDDEN
  60 int _bt_ctfser_increase_cur_packet_size(struct bt_ctfser *ctfser)
  61 {
  62         int ret;
  63
  64         BT_ASSERT(ctfser);
  65         BT_LOGV("Increasing stream file's current packet size: "
  66                 "path=\"%s\", fd=%d, "
  67                 "offset-in-cur-packet-bits=%" PRIu64 ", "
  68                 "cur-packet-size-bytes=%" PRIu64,
  69                 ctfser->path->str, ctfser->fd,
  70                 ctfser->offset_in_cur_packet_bits,
  71                 ctfser->cur_packet_size_bytes);
  72         ret = munmap_align(ctfser->base_mma);
  73         if (ret) {
  74                 BT_LOGE_ERRNO("Failed to perform an aligned memory unmapping",
  75                         ": ret=%d", ret);
  76                 goto end;
  77         }
  78
  79         ctfser->cur_packet_size_bytes += get_packet_size_increment_bytes();
  80
  81         do {
  82                 ret = bt_posix_fallocate(ctfser->fd, ctfser->mmap_offset,
  83                         ctfser->cur_packet_size_bytes);
  84         } while (ret == EINTR);
  85
  86         if (ret) {
  87                 BT_LOGE("Failed to preallocate memory space: ret=%d", ret);
  88                 goto end;
  89         }
  90
  91         mmap_align_ctfser(ctfser);
  92         if (ctfser->base_mma == MAP_FAILED) {
  93                 BT_LOGE_ERRNO("Failed to perform an aligned memory mapping",
  94                         ": ret=%d", ret);
  95                 ret = -1;
  96                 goto end;
  97         }
  98
  99         BT_LOGV("Increased packet size: "
 100                 "path=\"%s\", fd=%d, "
 101                 "offset-in-cur-packet-bits=%" PRIu64 ", "
 102                 "new-packet-size-bytes=%" PRIu64,
 103                 ctfser->path->str, ctfser->fd,
 104                 ctfser->offset_in_cur_packet_bits,
 105                 ctfser->cur_packet_size_bytes);
 106
 107 end:
 108         return ret;
 109 }
 110
 111 BT_HIDDEN
 112 int bt_ctfser_init(struct bt_ctfser *ctfser, const char *path)
 113 {
 114         int ret = 0;
 115
 116         BT_ASSERT(ctfser);
 117         memset(ctfser, 0, sizeof(*ctfser));
 118         ctfser->fd = open(path, O_RDWR | O_CREAT | O_TRUNC,
 119                 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
 120         if (ctfser->fd < 0) {
 121                 BT_LOGW_ERRNO("Failed to open stream file for writing",
 122                         ": path=\"%s\", ret=%d",
 123                         path, ctfser->fd);
 124                 ret = -1;
 125                 goto end;
 126         }
 127
 128         ctfser->path = g_string_new(path);
 129
 130 end:
 131         return ret;
 132 }
 133
 134 BT_HIDDEN
 135 int bt_ctfser_fini(struct bt_ctfser *ctfser)
 136 {
 137         int ret = 0;
 138
 139         if (ctfser->fd == -1) {
 140                 goto free_path;
 141         }
 142
 143         /*
 144          * Truncate the stream file's size to the minimum required to
 145          * fit the last packet as we might have grown it too much during
 146          * the last memory map.
 147          */
 148         do {
 149                 ret = ftruncate(ctfser->fd, ctfser->stream_size_bytes);
 150         } while (ret == -1 && errno == EINTR);
 151
 152         if (ret) {
 153                 BT_LOGE_ERRNO("Failed to truncate stream file",
 154                         ": ret=%d, size-bytes=%" PRIu64,
 155                         ret, ctfser->stream_size_bytes);
 156                 goto end;
 157         }
 158
 159         if (ctfser->base_mma) {
 160                 /* Unmap old base */
 161                 ret = munmap_align(ctfser->base_mma);
 162                 if (ret) {
 163                         BT_LOGE_ERRNO("Failed to unmap stream file",
 164                                 ": ret=%d, size-bytes=%" PRIu64,
 165                                 ret, ctfser->stream_size_bytes);
 166                         goto end;
 167                 }
 168
 169                 ctfser->base_mma = NULL;
 170         }
 171
 172         ret = close(ctfser->fd);
 173         if (ret) {
 174                 BT_LOGE_ERRNO("Failed to close stream file",
 175                         ": ret=%d", ret);
 176                 goto end;
 177         }
 178
 179         ctfser->fd = -1;
 180
 181 free_path:
 182         if (ctfser->path) {
 183                 g_string_free(ctfser->path, TRUE);
 184                 ctfser->path = NULL;
 185         }
 186
 187 end:
 188         return ret;
 189 }
 190
 191 BT_HIDDEN
 192 int bt_ctfser_open_packet(struct bt_ctfser *ctfser)
 193 {
 194         int ret = 0;
 195
 196         BT_LOGV("Opening packet: path=\"%s\", fd=%d, "
 197                 "prev-packet-size-bytes=%" PRIu64,
 198                 ctfser->path->str, ctfser->fd,
 199                 ctfser->prev_packet_size_bytes);
 200
 201         if (ctfser->base_mma) {
 202                 /* Unmap old base (previous packet) */
 203                 ret = munmap_align(ctfser->base_mma);
 204                 if (ret) {
 205                         BT_LOGE_ERRNO("Failed to unmap stream file",
 206                                 ": ret=%d, size-bytes=%" PRIu64,
 207                                 ret, ctfser->stream_size_bytes);
 208                         goto end;
 209                 }
 210
 211                 ctfser->base_mma = NULL;
 212         }
 213
 214         /*
 215          * Add the previous packet's size to the memory map address
 216          * offset to start writing immediately after it.
 217          */
 218         ctfser->mmap_offset += ctfser->prev_packet_size_bytes;
 219         ctfser->prev_packet_size_bytes = 0;
 220
 221         /* Make initial space for the current packet */
 222         ctfser->cur_packet_size_bytes = get_packet_size_increment_bytes();
 223
 224         do {
 225                 ret = bt_posix_fallocate(ctfser->fd, ctfser->mmap_offset,
 226                         ctfser->cur_packet_size_bytes);
 227         } while (ret == EINTR);
 228
 229         if (ret) {
 230                 BT_LOGE("Failed to preallocate memory space: ret=%d", ret);
 231                 goto end;
 232         }
 233
 234         /* Start writing at the beginning of the current packet */
 235         ctfser->offset_in_cur_packet_bits = 0;
 236
 237         /* Get new base address */
 238         mmap_align_ctfser(ctfser);
 239         if (ctfser->base_mma == MAP_FAILED) {
 240                 BT_LOGE_ERRNO("Failed to perform an aligned memory mapping",
 241                         ": ret=%d", ret);
 242                 ret = -1;
 243                 goto end;
 244         }
 245
 246         BT_LOGV("Opened packet: path=\"%s\", fd=%d, "
 247                 "cur-packet-size-bytes=%" PRIu64,
 248                 ctfser->path->str, ctfser->fd,
 249                 ctfser->cur_packet_size_bytes);
 250
 251 end:
 252         return ret;
 253 }
 254
 255 BT_HIDDEN
 256 void bt_ctfser_close_current_packet(struct bt_ctfser *ctfser,
 257                 uint64_t packet_size_bytes)
 258 {
 259         BT_LOGV("Closing packet: path=\"%s\", fd=%d, "
 260                 "offset-in-cur-packet-bits=%" PRIu64
 261                 "cur-packet-size-bytes=%" PRIu64,
 262                 ctfser->path->str, ctfser->fd,
 263                 ctfser->offset_in_cur_packet_bits,
 264                 ctfser->cur_packet_size_bytes);
 265
 266         /*
 267          * This will be used during the next call to
 268          * bt_ctfser_open_packet(): we add
 269          * `ctfser->prev_packet_size_bytes` to the current memory map
 270          * address offset (first byte of _this_ packet), effectively
 271          * making _this_ packet the required size.
 272          */
 273         ctfser->prev_packet_size_bytes = packet_size_bytes;
 274         ctfser->stream_size_bytes += packet_size_bytes;
 275         BT_LOGV("Closed packet: path=\"%s\", fd=%d, "
 276                 "stream-file-size-bytes=%" PRIu64,
 277                 ctfser->path->str, ctfser->fd,
 278                 ctfser->stream_size_bytes);
 279 }