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