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