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 <babeltrace2/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 <babeltrace2/babeltrace-internal.h>
  41 #include <babeltrace2/common-internal.h>
  42 #include <babeltrace2/ctfser-internal.h>
  43 #include <babeltrace2/compat/unistd-internal.h>
  44 #include <babeltrace2/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,
  56                 PROT_READ | PROT_WRITE,
  57                 MAP_SHARED, ctfser->fd, ctfser->mmap_offset);
  58 }
  59
  60 BT_HIDDEN
  61 int _bt_ctfser_increase_cur_packet_size(struct bt_ctfser *ctfser)
  62 {
  63         int ret;
  64
  65         BT_ASSERT(ctfser);
  66         BT_LOGV("Increasing stream file's current packet size: "
  67                 "path=\"%s\", fd=%d, "
  68                 "offset-in-cur-packet-bits=%" PRIu64 ", "
  69                 "cur-packet-size-bytes=%" PRIu64,
  70                 ctfser->path->str, ctfser->fd,
  71                 ctfser->offset_in_cur_packet_bits,
  72                 ctfser->cur_packet_size_bytes);
  73         ret = munmap_align(ctfser->base_mma);
  74         if (ret) {
  75                 BT_LOGE_ERRNO("Failed to perform an aligned memory unmapping",
  76                         ": ret=%d", ret);
  77                 goto end;
  78         }
  79
  80         ctfser->cur_packet_size_bytes += get_packet_size_increment_bytes();
  81
  82         do {
  83                 ret = bt_posix_fallocate(ctfser->fd, ctfser->mmap_offset,
  84                         ctfser->cur_packet_size_bytes);
  85         } while (ret == EINTR);
  86
  87         if (ret) {
  88                 BT_LOGE("Failed to preallocate memory space: ret=%d", ret);
  89                 goto end;
  90         }
  91
  92         mmap_align_ctfser(ctfser);
  93         if (ctfser->base_mma == MAP_FAILED) {
  94                 BT_LOGE_ERRNO("Failed to perform an aligned memory mapping",
  95                         ": ret=%d", ret);
  96                 ret = -1;
  97                 goto end;
  98         }
  99
 100         BT_LOGV("Increased packet size: "
 101                 "path=\"%s\", fd=%d, "
 102                 "offset-in-cur-packet-bits=%" PRIu64 ", "
 103                 "new-packet-size-bytes=%" PRIu64,
 104                 ctfser->path->str, ctfser->fd,
 105                 ctfser->offset_in_cur_packet_bits,
 106                 ctfser->cur_packet_size_bytes);
 107
 108 end:
 109         return ret;
 110 }
 111
 112 BT_HIDDEN
 113 int bt_ctfser_init(struct bt_ctfser *ctfser, const char *path)
 114 {
 115         int ret = 0;
 116
 117         BT_ASSERT(ctfser);
 118         memset(ctfser, 0, sizeof(*ctfser));
 119         ctfser->fd = open(path, O_RDWR | O_CREAT | O_TRUNC,
 120                 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
 121         if (ctfser->fd < 0) {
 122                 BT_LOGW_ERRNO("Failed to open stream file for writing",
 123                         ": path=\"%s\", ret=%d",
 124                         path, ctfser->fd);
 125                 ret = -1;
 126                 goto end;
 127         }
 128
 129         ctfser->path = g_string_new(path);
 130
 131 end:
 132         return ret;
 133 }
 134
 135 BT_HIDDEN
 136 int bt_ctfser_fini(struct bt_ctfser *ctfser)
 137 {
 138         int ret = 0;
 139
 140         if (ctfser->fd == -1) {
 141                 goto free_path;
 142         }
 143
 144         /*
 145          * Truncate the stream file's size to the minimum required to
 146          * fit the last packet as we might have grown it too much during
 147          * the last memory map.
 148          */
 149         do {
 150                 ret = ftruncate(ctfser->fd, ctfser->stream_size_bytes);
 151         } while (ret == -1 && errno == EINTR);
 152
 153         if (ret) {
 154                 BT_LOGE_ERRNO("Failed to truncate stream file",
 155                         ": ret=%d, size-bytes=%" PRIu64,
 156                         ret, ctfser->stream_size_bytes);
 157                 goto end;
 158         }
 159
 160         if (ctfser->base_mma) {
 161                 /* Unmap old base */
 162                 ret = munmap_align(ctfser->base_mma);
 163                 if (ret) {
 164                         BT_LOGE_ERRNO("Failed to unmap stream file",
 165                                 ": ret=%d, size-bytes=%" PRIu64,
 166                                 ret, ctfser->stream_size_bytes);
 167                         goto end;
 168                 }
 169
 170                 ctfser->base_mma = NULL;
 171         }
 172
 173         ret = close(ctfser->fd);
 174         if (ret) {
 175                 BT_LOGE_ERRNO("Failed to close stream file",
 176                         ": ret=%d", ret);
 177                 goto end;
 178         }
 179
 180         ctfser->fd = -1;
 181
 182 free_path:
 183         if (ctfser->path) {
 184                 g_string_free(ctfser->path, TRUE);
 185                 ctfser->path = NULL;
 186         }
 187
 188 end:
 189         return ret;
 190 }
 191
 192 BT_HIDDEN
 193 int bt_ctfser_open_packet(struct bt_ctfser *ctfser)
 194 {
 195         int ret = 0;
 196
 197         BT_LOGV("Opening packet: path=\"%s\", fd=%d, "
 198                 "prev-packet-size-bytes=%" PRIu64,
 199                 ctfser->path->str, ctfser->fd,
 200                 ctfser->prev_packet_size_bytes);
 201
 202         if (ctfser->base_mma) {
 203                 /* Unmap old base (previous packet) */
 204                 ret = munmap_align(ctfser->base_mma);
 205                 if (ret) {
 206                         BT_LOGE_ERRNO("Failed to unmap stream file",
 207                                 ": ret=%d, size-bytes=%" PRIu64,
 208                                 ret, ctfser->stream_size_bytes);
 209                         goto end;
 210                 }
 211
 212                 ctfser->base_mma = NULL;
 213         }
 214
 215         /*
 216          * Add the previous packet's size to the memory map address
 217          * offset to start writing immediately after it.
 218          */
 219         ctfser->mmap_offset += ctfser->prev_packet_size_bytes;
 220         ctfser->prev_packet_size_bytes = 0;
 221
 222         /* Make initial space for the current packet */
 223         ctfser->cur_packet_size_bytes = get_packet_size_increment_bytes();
 224
 225         do {
 226                 ret = bt_posix_fallocate(ctfser->fd, ctfser->mmap_offset,
 227                         ctfser->cur_packet_size_bytes);
 228         } while (ret == EINTR);
 229
 230         if (ret) {
 231                 BT_LOGE("Failed to preallocate memory space: ret=%d", ret);
 232                 goto end;
 233         }
 234
 235         /* Start writing at the beginning of the current packet */
 236         ctfser->offset_in_cur_packet_bits = 0;
 237
 238         /* Get new base address */
 239         mmap_align_ctfser(ctfser);
 240         if (ctfser->base_mma == MAP_FAILED) {
 241                 BT_LOGE_ERRNO("Failed to perform an aligned memory mapping",
 242                         ": ret=%d", ret);
 243                 ret = -1;
 244                 goto end;
 245         }
 246
 247         BT_LOGV("Opened packet: path=\"%s\", fd=%d, "
 248                 "cur-packet-size-bytes=%" PRIu64,
 249                 ctfser->path->str, ctfser->fd,
 250                 ctfser->cur_packet_size_bytes);
 251
 252 end:
 253         return ret;
 254 }
 255
 256 BT_HIDDEN
 257 void bt_ctfser_close_current_packet(struct bt_ctfser *ctfser,
 258                 uint64_t packet_size_bytes)
 259 {
 260         BT_LOGV("Closing packet: path=\"%s\", fd=%d, "
 261                 "offset-in-cur-packet-bits=%" PRIu64
 262                 "cur-packet-size-bytes=%" PRIu64,
 263                 ctfser->path->str, ctfser->fd,
 264                 ctfser->offset_in_cur_packet_bits,
 265                 ctfser->cur_packet_size_bytes);
 266
 267         /*
 268          * This will be used during the next call to
 269          * bt_ctfser_open_packet(): we add
 270          * `ctfser->prev_packet_size_bytes` to the current memory map
 271          * address offset (first byte of _this_ packet), effectively
 272          * making _this_ packet the required size.
 273          */
 274         ctfser->prev_packet_size_bytes = packet_size_bytes;
 275         ctfser->stream_size_bytes += packet_size_bytes;
 276         BT_LOGV("Closed packet: path=\"%s\", fd=%d, "
 277                 "stream-file-size-bytes=%" PRIu64,
 278                 ctfser->path->str, ctfser->fd,
 279                 ctfser->stream_size_bytes);
 280 }