include/babeltrace/ctf-writer/serialize-internal.h

   1 #ifndef BABELTRACE_CTF_WRITER_SERIALIZE_INTERNAL_H
   2 #define BABELTRACE_CTF_WRITER_SERIALIZE_INTERNAL_H
   3
   4 /*
   5  * Copyright 2017 Philippe Proulx <pproulx@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  * The Common Trace Format (CTF) Specification is available at
  26  * http://www.efficios.com/ctf
  27  */
  28
  29 #include <stdlib.h>
  30 #include <stdint.h>
  31 #include <limits.h>
  32 #include <babeltrace/compat/mman-internal.h>
  33 #include <sys/types.h>
  34 #include <sys/stat.h>
  35 #include <fcntl.h>
  36 #include <babeltrace/align-internal.h>
  37 #include <babeltrace/endian-internal.h>
  38 #include <babeltrace/common-internal.h>
  39 #include <babeltrace/mmap-align-internal.h>
  40 #include <babeltrace/types.h>
  41 #include <babeltrace/ctf-writer/field-types.h>
  42 #include <babeltrace/ctf-writer/fields-internal.h>
  43 #include <babeltrace/ctf-writer/fields.h>
  44 #include <babeltrace/assert-internal.h>
  45
  46 #define PACKET_LEN_INCREMENT    (bt_common_get_page_size() * 8 * CHAR_BIT)
  47
  48 #if (BYTE_ORDER == BIG_ENDIAN)
  49 # define BT_CTF_MY_BYTE_ORDER   BT_CTF_BYTE_ORDER_BIG_ENDIAN
  50 #else
  51 # define BT_CTF_MY_BYTE_ORDER   BT_CTF_BYTE_ORDER_LITTLE_ENDIAN
  52 #endif
  53
  54 struct bt_ctf_stream_pos {
  55         int fd;
  56         int prot;               /* mmap protection */
  57         int flags;              /* mmap flags */
  58
  59         /* Current position */
  60         off_t mmap_offset;      /* mmap offset in the file, in bytes */
  61         off_t mmap_base_offset; /* offset of start of packet in mmap, in bytes */
  62         uint64_t packet_size;   /* current packet size, in bits */
  63         int64_t offset;         /* offset from base, in bits. EOF for end of file. */
  64         struct mmap_align *base_mma;/* mmap base address */
  65 };
  66
  67 BT_HIDDEN
  68 int bt_ctf_field_integer_write(struct bt_ctf_field_common *field,
  69                 struct bt_ctf_stream_pos *pos,
  70                 enum bt_ctf_byte_order native_byte_order);
  71
  72 BT_HIDDEN
  73 int bt_ctf_field_floating_point_write(struct bt_ctf_field_common *field,
  74                 struct bt_ctf_stream_pos *pos,
  75                 enum bt_ctf_byte_order native_byte_order);
  76
  77 static inline
  78 int bt_ctf_stream_pos_access_ok(struct bt_ctf_stream_pos *pos, uint64_t bit_len)
  79 {
  80         uint64_t max_len;
  81
  82         if (unlikely(pos->offset == EOF))
  83                 return 0;
  84
  85         if (pos->prot == PROT_READ) {
  86                 /*
  87                  * Reads may only reach up to the "content_size",
  88                  * regardless of the packet_size.
  89                  */
  90                 max_len = pos->offset;
  91         } else {
  92                 /* Writes may take place up to the end of the packet. */
  93                 max_len = pos->packet_size;
  94         }
  95         if (unlikely(pos->offset < 0 || bit_len > INT64_MAX - pos->offset)) {
  96                 return 0;
  97         }
  98         if (unlikely(pos->offset + bit_len > max_len))
  99                 return 0;
 100         return 1;
 101 }
 102
 103 static inline
 104 int bt_ctf_stream_pos_move(struct bt_ctf_stream_pos *pos, uint64_t bit_offset)
 105 {
 106         int ret = 0;
 107
 108         ret = bt_ctf_stream_pos_access_ok(pos, bit_offset);
 109         if (!ret) {
 110                 goto end;
 111         }
 112         pos->offset += bit_offset;
 113 end:
 114         return ret;
 115 }
 116
 117 static inline
 118 int bt_ctf_stream_pos_align(struct bt_ctf_stream_pos *pos, uint64_t bit_offset)
 119 {
 120         return bt_ctf_stream_pos_move(pos,
 121                 offset_align(pos->offset, bit_offset));
 122 }
 123
 124 static inline
 125 char *bt_ctf_stream_pos_get_addr(struct bt_ctf_stream_pos *pos)
 126 {
 127         /* Only makes sense to get the address after aligning on CHAR_BIT */
 128         BT_ASSERT(!(pos->offset % CHAR_BIT));
 129         return ((char *) mmap_align_addr(pos->base_mma)) +
 130                 pos->mmap_base_offset + (pos->offset / CHAR_BIT);
 131 }
 132
 133 static inline
 134 int bt_ctf_stream_pos_init(struct bt_ctf_stream_pos *pos,
 135                 int fd, int open_flags)
 136 {
 137         pos->fd = fd;
 138
 139         switch (open_flags & O_ACCMODE) {
 140         case O_RDONLY:
 141                 pos->prot = PROT_READ;
 142                 pos->flags = MAP_PRIVATE;
 143                 break;
 144         case O_RDWR:
 145                 pos->prot = PROT_READ | PROT_WRITE;
 146                 pos->flags = MAP_SHARED;
 147                 break;
 148         default:
 149                 abort();
 150         }
 151
 152         return 0;
 153 }
 154
 155 static inline
 156 int bt_ctf_stream_pos_fini(struct bt_ctf_stream_pos *pos)
 157 {
 158         if (pos->base_mma) {
 159                 int ret;
 160
 161                 /* unmap old base */
 162                 ret = munmap_align(pos->base_mma);
 163                 if (ret) {
 164                         return -1;
 165                 }
 166         }
 167
 168         return 0;
 169 }
 170
 171 BT_HIDDEN
 172 void bt_ctf_stream_pos_packet_seek(struct bt_ctf_stream_pos *pos, size_t index,
 173         int whence);
 174
 175 #endif /* BABELTRACE_CTF_WRITER_SERIALIZE_INTERNAL_H */