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 <sys/types.h>
  24 #include <sys/stat.h>
  25 #include <fcntl.h>
  26 #include <sys/mman.h>
  27 #include <errno.h>
  28 #include <stdint.h>
  29 #include <unistd.h>
  30 #include <glib.h>
  31 #include <stdio.h>
  32
  33 struct packet_index {
  34         off_t offset;           /* offset of the packet in the file, in bytes */
  35         off_t data_offset;      /* offset of data within the packet */
  36         size_t packet_size;     /* packet size, in bits */
  37         size_t content_size;    /* content size, in bits */
  38 };
  39
  40 /*
  41  * Always update ctf_stream_pos with ctf_move_pos and ctf_init_pos.
  42  */
  43 struct ctf_stream_pos {
  44         struct stream_pos parent;
  45         int fd;                 /* backing file fd. -1 if unset. */
  46         GArray *packet_index;   /* contains struct packet_index */
  47         int prot;               /* mmap protection */
  48         int flags;              /* mmap flags */
  49
  50         /* Current position */
  51         off_t mmap_offset;      /* mmap offset in the file, in bytes */
  52         size_t packet_size;     /* current packet size, in bits */
  53         size_t content_size;    /* current content size, in bits */
  54         uint32_t *content_size_loc; /* pointer to current content size */
  55         char *base;             /* mmap base address */
  56         ssize_t offset;         /* offset from base, in bits. -EOF for end of file. */
  57         size_t cur_index;       /* current index in packet index */
  58
  59         int dummy;              /* dummy position, for length calculation */
  60 };
  61
  62 static inline
  63 struct ctf_stream_pos *ctf_pos(struct stream_pos *pos)
  64 {
  65         return container_of(pos, struct ctf_stream_pos, parent);
  66 }
  67
  68 int ctf_integer_read(struct stream_pos *pos, struct definition *definition);
  69 int ctf_integer_write(struct stream_pos *pos, struct definition *definition);
  70 int ctf_float_read(struct stream_pos *pos, struct definition *definition);
  71 int ctf_float_write(struct stream_pos *pos, struct definition *definition);
  72 int ctf_string_read(struct stream_pos *pos, struct definition *definition);
  73 int ctf_string_write(struct stream_pos *pos, struct definition *definition);
  74 int ctf_enum_read(struct stream_pos *pos, struct definition *definition);
  75 int ctf_enum_write(struct stream_pos *pos, struct definition *definition);
  76 int ctf_struct_rw(struct stream_pos *pos, struct definition *definition);
  77 int ctf_variant_rw(struct stream_pos *pos, struct definition *definition);
  78 int ctf_array_rw(struct stream_pos *pos, struct definition *definition);
  79 int ctf_sequence_rw(struct stream_pos *pos, struct definition *definition);
  80
  81 void ctf_move_pos_slow(struct ctf_stream_pos *pos, size_t offset, int whence);
  82
  83 void ctf_init_pos(struct ctf_stream_pos *pos, int fd, int open_flags);
  84 void ctf_fini_pos(struct ctf_stream_pos *pos);
  85
  86 /*
  87  * move_pos - move position of a relative bit offset
  88  *
  89  * TODO: allow larger files by updating base too.
  90  */
  91 static inline
  92 void ctf_move_pos(struct ctf_stream_pos *pos, size_t bit_offset)
  93 {
  94         if (pos->offset == -EOF)
  95                 return;
  96
  97         if (pos->fd >= 0) {
  98                 if (((pos->prot == PROT_READ)
  99                       && (pos->offset + bit_offset >= pos->content_size))
 100                     || ((pos->prot == PROT_WRITE)
 101                       && (pos->offset + bit_offset >= pos->packet_size))) {
 102                         ctf_move_pos_slow(pos, bit_offset, SEEK_CUR);
 103                         return;
 104                 }
 105         }
 106         pos->offset += bit_offset;
 107 }
 108
 109 /*
 110  * align_pos - align position on a bit offset (> 0)
 111  *
 112  * TODO: allow larger files by updating base too.
 113  */
 114 static inline
 115 void ctf_align_pos(struct ctf_stream_pos *pos, size_t bit_offset)
 116 {
 117         ctf_move_pos(pos, offset_align(pos->offset, bit_offset));
 118 }
 119
 120 static inline
 121 char *ctf_get_pos_addr(struct ctf_stream_pos *pos)
 122 {
 123         /* Only makes sense to get the address after aligning on CHAR_BIT */
 124         assert(!(pos->offset % CHAR_BIT));
 125         return pos->base + (pos->offset / CHAR_BIT);
 126 }
 127
 128 static inline
 129 void ctf_dummy_pos(struct ctf_stream_pos *pos, struct ctf_stream_pos *dummy)
 130 {
 131         memcpy(dummy, pos, sizeof(struct ctf_stream_pos));
 132         dummy->dummy = 1;
 133         dummy->fd = -1;
 134 }
 135
 136 /*
 137  * Check if current packet can hold data.
 138  * Returns 0 for success, negative error otherwise.
 139  */
 140 static inline
 141 int ctf_pos_packet(struct ctf_stream_pos *dummy)
 142 {
 143         if (dummy->offset > dummy->packet_size)
 144                 return -ENOSPC;
 145         return 0;
 146 }
 147
 148 static inline
 149 void ctf_pos_pad_packet(struct ctf_stream_pos *pos)
 150 {
 151         ctf_move_pos(pos, pos->packet_size - pos->offset);
 152 }
 153
 154 static inline
 155 int ctf_pos_access_ok(struct ctf_stream_pos *pos, size_t bit_len)
 156 {
 157         if (pos->offset == -EOF)
 158                 return 0;
 159         if (pos->offset + bit_len > pos->packet_size)
 160                 return 0;
 161         return 1;
 162 }
 163
 164 #endif /* _BABELTRACE_CTF_TYPES_H */