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/mman.h>
  24 #include <errno.h>
  25 #include <stdint.h>
  26 #include <unistd.h>
  27 #include <glib.h>
  28
  29 struct packet_index {
  30         off_t offset;           /* offset of the packet in the file, in bytes */
  31         size_t packet_size;     /* packet size, in bits */
  32         size_t content_size;    /* content size, in bits */
  33 };
  34
  35 /*
  36  * Always update ctf_stream_pos with ctf_move_pos and ctf_init_pos.
  37  */
  38 struct ctf_stream_pos {
  39         struct stream_pos parent;
  40         int fd;                 /* backing file fd. -1 if unset. */
  41         GArray *packet_index;   /* contains struct packet_index */
  42         int prot;               /* mmap protection */
  43         int flags;              /* mmap flags */
  44
  45         /* Current position */
  46         off_t mmap_offset;      /* mmap offset in the file, in bytes */
  47         size_t packet_size;     /* current packet size, in bits */
  48         size_t content_size;    /* current content size, in bits */
  49         uint32_t *content_size_loc; /* pointer to current content size */
  50         char *base;             /* mmap base address */
  51         size_t offset;          /* offset from base, in bits */
  52         size_t cur_index;       /* current index in packet index */
  53
  54         int dummy;              /* dummy position, for length calculation */
  55 };
  56
  57 static inline
  58 struct ctf_stream_pos *ctf_pos(struct stream_pos *pos)
  59 {
  60         return container_of(pos, struct ctf_stream_pos, parent);
  61 }
  62
  63 /*
  64  * IMPORTANT: All lengths (len) and offsets (start, end) are expressed in bits,
  65  *            *not* in bytes.
  66  *
  67  * All write primitives, as well as read for dynamically sized entities, can
  68  * receive a NULL ptr/dest parameter. In this case, no write is performed, but
  69  * the size is returned.
  70  */
  71
  72 uint64_t ctf_uint_read(struct stream_pos *pos,
  73                 const struct declaration_integer *integer_declaration);
  74 int64_t ctf_int_read(struct stream_pos *pos,
  75                 const struct declaration_integer *integer_declaration);
  76 void ctf_uint_write(struct stream_pos *pos,
  77                 const struct declaration_integer *integer_declaration,
  78                 uint64_t v);
  79 void ctf_int_write(struct stream_pos *pos,
  80                 const struct declaration_integer *integer_declaration,
  81                 int64_t v);
  82
  83 double ctf_double_read(struct stream_pos *pos,
  84                         const struct declaration_float *src);
  85 void ctf_double_write(struct stream_pos *pos,
  86                 const struct declaration_float *dest,
  87                 double v);
  88 long double ctf_ldouble_read(struct stream_pos *pos,
  89                              const struct declaration_float *src);
  90 void ctf_ldouble_write(struct stream_pos *pos,
  91                 const struct declaration_float *dest,
  92                 long double v);
  93 void ctf_float_copy(struct stream_pos *destp,
  94                 struct stream_pos *srcp,
  95                 const struct declaration_float *float_declaration);
  96
  97 void ctf_string_copy(struct stream_pos *dest, struct stream_pos *src,
  98                 const struct declaration_string *string_declaration);
  99 void ctf_string_read(char **dest, struct stream_pos *src,
 100                 const struct declaration_string *string_declaration);
 101 void ctf_string_write(struct stream_pos *dest, const char *src,
 102                 const struct declaration_string *string_declaration);
 103 void ctf_string_free_temp(char *string);
 104
 105 GArray *ctf_enum_read(struct stream_pos *pos,
 106                 const struct declaration_enum *src);
 107 void ctf_enum_write(struct stream_pos *pos,
 108                 const struct declaration_enum *dest,
 109                 GQuark q);
 110 void ctf_struct_begin(struct stream_pos *pos,
 111                 const struct declaration_struct *struct_declaration);
 112 void ctf_struct_end(struct stream_pos *pos,
 113                 const struct declaration_struct *struct_declaration);
 114 void ctf_variant_begin(struct stream_pos *pos,
 115                 const struct declaration_variant *variant_declaration);
 116 void ctf_variant_end(struct stream_pos *pos,
 117                 const struct declaration_variant *variant_declaration);
 118 void ctf_array_begin(struct stream_pos *pos,
 119                 const struct declaration_array *array_declaration);
 120 void ctf_array_end(struct stream_pos *pos,
 121                 const struct declaration_array *array_declaration);
 122 void ctf_sequence_begin(struct stream_pos *pos,
 123                 const struct declaration_sequence *sequence_declaration);
 124 void ctf_sequence_end(struct stream_pos *pos,
 125                 const struct declaration_sequence *sequence_declaration);
 126
 127 void ctf_move_pos_slow(struct ctf_stream_pos *pos, size_t offset);
 128
 129 void ctf_init_pos(struct ctf_stream_pos *pos, int fd);
 130 void ctf_fini_pos(struct ctf_stream_pos *pos);
 131
 132 /*
 133  * move_pos - move position of a relative bit offset
 134  *
 135  * TODO: allow larger files by updating base too.
 136  */
 137 static inline
 138 void ctf_move_pos(struct ctf_stream_pos *pos, size_t bit_offset)
 139 {
 140         if (pos->fd >= 0) {
 141                 if (((pos->prot == PROT_READ)
 142                       && (pos->offset + bit_offset >= pos->content_size))
 143                     || ((pos->prot == PROT_WRITE)
 144                       && (pos->offset + bit_offset >= pos->packet_size))) {
 145                         ctf_move_pos_slow(pos, bit_offset);
 146                         return;
 147                 }
 148         }
 149         pos->offset += bit_offset;
 150 }
 151
 152 /*
 153  * align_pos - align position on a bit offset (> 0)
 154  *
 155  * TODO: allow larger files by updating base too.
 156  */
 157 static inline
 158 void ctf_align_pos(struct ctf_stream_pos *pos, size_t bit_offset)
 159 {
 160         ctf_move_pos(pos, offset_align(pos->offset, bit_offset));
 161 }
 162
 163 static inline
 164 char *ctf_get_pos_addr(struct ctf_stream_pos *pos)
 165 {
 166         /* Only makes sense to get the address after aligning on CHAR_BIT */
 167         assert(!(pos->offset % CHAR_BIT));
 168         return pos->base + (pos->offset / CHAR_BIT);
 169 }
 170
 171 static inline
 172 void ctf_dummy_pos(struct ctf_stream_pos *pos, struct ctf_stream_pos *dummy)
 173 {
 174         memcpy(dummy, pos, sizeof(struct ctf_stream_pos));
 175         dummy->dummy = 1;
 176         dummy->fd = -1;
 177 }
 178
 179 /*
 180  * Check if current packet can hold data.
 181  * Returns 0 for success, negative error otherwise.
 182  */
 183 static inline
 184 int ctf_pos_packet(struct ctf_stream_pos *dummy)
 185 {
 186         if (dummy->offset > dummy->packet_size)
 187                 return -ENOSPC;
 188         return 0;
 189 }
 190
 191 static inline
 192 void ctf_pos_pad_packet(struct ctf_stream_pos *pos)
 193 {
 194         ctf_move_pos(pos, pos->packet_size - pos->offset);
 195 }
 196
 197 #endif /* _BABELTRACE_CTF_TYPES_H */