include/babeltrace/ctf/types.h

   1 #ifndef _BABELTRACE_CTF_TYPES_H
   2 #define _BABELTRACE_CTF_TYPES_H
   3
   4 /*
   5  * Common Trace Format
   6  *
   7  * Type header
   8  *
   9  * Copyright 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  10  *
  11  * Permission is hereby granted, free of charge, to any person obtaining a copy
  12  * of this software and associated documentation files (the "Software"), to deal
  13  * in the Software without restriction, including without limitation the rights
  14  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  15  * copies of the Software, and to permit persons to whom the Software is
  16  * furnished to do so, subject to the following conditions:
  17  *
  18  * The above copyright notice and this permission notice shall be included in
  19  * all copies or substantial portions of the Software.
  20  */
  21
  22 #include <babeltrace/types.h>
  23 #include <babeltrace/babeltrace-internal.h>
  24 #include <sys/types.h>
  25 #include <sys/stat.h>
  26 #include <fcntl.h>
  27 #include <sys/mman.h>
  28 #include <errno.h>
  29 #include <stdint.h>
  30 #include <unistd.h>
  31 #include <glib.h>
  32 #include <stdio.h>
  33
  34 struct bt_stream_callbacks;
  35
  36 struct packet_index {
  37         off_t offset;           /* offset of the packet in the file, in bytes */
  38         off_t data_offset;      /* offset of data within the packet, in bits */
  39         size_t packet_size;     /* packet size, in bits */
  40         size_t content_size;    /* content size, in bits */
  41         uint64_t timestamp_begin;
  42         uint64_t timestamp_end;
  43         uint32_t events_discarded;
  44 };
  45
  46 /*
  47  * Always update ctf_stream_pos with ctf_move_pos and ctf_init_pos.
  48  */
  49 struct ctf_stream_pos {
  50         struct stream_pos parent;
  51         int fd;                 /* backing file fd. -1 if unset. */
  52         GArray *packet_index;   /* contains struct packet_index */
  53         int prot;               /* mmap protection */
  54         int flags;              /* mmap flags */
  55
  56         /* Current position */
  57         off_t mmap_offset;      /* mmap offset in the file, in bytes */
  58         size_t packet_size;     /* current packet size, in bits */
  59         size_t content_size;    /* current content size, in bits */
  60         uint32_t *content_size_loc; /* pointer to current content size */
  61         char *base;             /* mmap base address */
  62         ssize_t offset;         /* offset from base, in bits. EOF for end of file. */
  63         size_t cur_index;       /* current index in packet index */
  64         void (*move_pos_slow)(struct ctf_stream_pos *pos, size_t offset,
  65                         int whence); /* function called to switch packet */
  66
  67         int dummy;              /* dummy position, for length calculation */
  68         struct bt_stream_callbacks *cb; /* Callbacks registered for iterator. */
  69 };
  70
  71 static inline
  72 struct ctf_stream_pos *ctf_pos(struct stream_pos *pos)
  73 {
  74         return container_of(pos, struct ctf_stream_pos, parent);
  75 }
  76
  77 int ctf_integer_read(struct stream_pos *pos, struct definition *definition);
  78 int ctf_integer_write(struct stream_pos *pos, struct definition *definition);
  79 int ctf_float_read(struct stream_pos *pos, struct definition *definition);
  80 int ctf_float_write(struct stream_pos *pos, struct definition *definition);
  81 int ctf_string_read(struct stream_pos *pos, struct definition *definition);
  82 int ctf_string_write(struct stream_pos *pos, struct definition *definition);
  83 int ctf_enum_read(struct stream_pos *pos, struct definition *definition);
  84 int ctf_enum_write(struct stream_pos *pos, struct definition *definition);
  85 int ctf_struct_rw(struct stream_pos *pos, struct definition *definition);
  86 int ctf_variant_rw(struct stream_pos *pos, struct definition *definition);
  87 int ctf_array_read(struct stream_pos *pos, struct definition *definition);
  88 int ctf_array_write(struct stream_pos *pos, struct definition *definition);
  89 int ctf_sequence_read(struct stream_pos *pos, struct definition *definition);
  90 int ctf_sequence_write(struct stream_pos *pos, struct definition *definition);
  91
  92 void ctf_move_pos_slow(struct ctf_stream_pos *pos, size_t offset, int whence);
  93
  94 void ctf_init_pos(struct ctf_stream_pos *pos, int fd, int open_flags);
  95 void ctf_fini_pos(struct ctf_stream_pos *pos);
  96
  97 /*
  98  * move_pos - move position of a relative bit offset
  99  *
 100  * TODO: allow larger files by updating base too.
 101  */
 102 static inline
 103 void ctf_move_pos(struct ctf_stream_pos *pos, size_t bit_offset)
 104 {
 105         printf_debug("ctf_move_pos test EOF: %zd\n", pos->offset);
 106         if (unlikely(pos->offset == EOF))
 107                 return;
 108
 109         if (pos->fd >= 0) {
 110                 /*
 111                  * PROT_READ ctf_move_pos_slow is called from within
 112                  * ctf_pos_get_event so end of packet does not change
 113                  * the packet context on for the last event of the
 114                  * packet.
 115                  */
 116                 if ((pos->prot == PROT_WRITE)
 117                         && (unlikely(pos->offset + bit_offset >= pos->packet_size))) {
 118                         printf_debug("ctf_move_pos_slow (before call): %zd\n",
 119                                      pos->offset);
 120                         ctf_move_pos_slow(pos, bit_offset, SEEK_CUR);
 121                         printf_debug("ctf_move_pos_slow (after call): %zd\n",
 122                                      pos->offset);
 123                         return;
 124                 }
 125         }
 126         pos->offset += bit_offset;
 127         printf_debug("ctf_move_pos after increment: %zd\n", pos->offset);
 128 }
 129
 130 /*
 131  * align_pos - align position on a bit offset (> 0)
 132  *
 133  * TODO: allow larger files by updating base too.
 134  */
 135 static inline
 136 void ctf_align_pos(struct ctf_stream_pos *pos, size_t bit_offset)
 137 {
 138         ctf_move_pos(pos, offset_align(pos->offset, bit_offset));
 139 }
 140
 141 static inline
 142 char *ctf_get_pos_addr(struct ctf_stream_pos *pos)
 143 {
 144         /* Only makes sense to get the address after aligning on CHAR_BIT */
 145         assert(!(pos->offset % CHAR_BIT));
 146         return pos->base + (pos->offset / CHAR_BIT);
 147 }
 148
 149 static inline
 150 void ctf_dummy_pos(struct ctf_stream_pos *pos, struct ctf_stream_pos *dummy)
 151 {
 152         memcpy(dummy, pos, sizeof(struct ctf_stream_pos));
 153         dummy->dummy = 1;
 154         dummy->fd = -1;
 155 }
 156
 157 /*
 158  * Check if current packet can hold data.
 159  * Returns 0 for success, negative error otherwise.
 160  */
 161 static inline
 162 int ctf_pos_packet(struct ctf_stream_pos *dummy)
 163 {
 164         if (unlikely(dummy->offset > dummy->packet_size))
 165                 return -ENOSPC;
 166         return 0;
 167 }
 168
 169 static inline
 170 void ctf_pos_pad_packet(struct ctf_stream_pos *pos)
 171 {
 172         ctf_move_pos(pos, pos->packet_size - pos->offset);
 173 }
 174
 175 static inline
 176 int ctf_pos_access_ok(struct ctf_stream_pos *pos, size_t bit_len)
 177 {
 178         if (unlikely(pos->offset == EOF))
 179                 return 0;
 180         if (unlikely(pos->offset + bit_len > pos->packet_size))
 181                 return 0;
 182         return 1;
 183 }
 184
 185 /*
 186  * Update the stream position for to the current event. This moves to
 187  * the next packet if we are located at the end of the current packet.
 188  */
 189 static inline
 190 void ctf_pos_get_event(struct ctf_stream_pos *pos)
 191 {
 192         assert(pos->offset <= pos->content_size);
 193         if (pos->offset == pos->content_size) {
 194                 printf_debug("ctf_move_pos_slow (before call): %zd\n",
 195                              pos->offset);
 196                 pos->move_pos_slow(pos, 0, SEEK_CUR);
 197                 printf_debug("ctf_move_pos_slow (after call): %zd\n",
 198                              pos->offset);
 199         }
 200 }
 201
 202 #endif /* _BABELTRACE_CTF_TYPES_H */