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