std-ext-lib.txt

   1 Common Trace Format - Standards, Extensions and Libraries
   2 Mathieu Desnoyers
   3 September 26, 2010
   4
   5 This document describes the CTF library dependencies on standards, extensions
   6 and libraries.
   7
   8
   9 ** Standards
  10
  11 * C99
  12
  13 This library is C99 compliant. A non-documented non-compliance should be
  14 reported as a bug. See the ISO/IEC 9899:TC2 publication:
  15
  16   http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1124.pdf
  17
  18
  19 * IEEE 754-2008
  20
  21 The IEEE 754-2008 standard is used for binary floating point arithmetic
  22 representation. See:
  23
  24   http://grouper.ieee.org/groups/754/
  25
  26
  27 * GNU/C extensions
  28
  29 This library uses some widely GNU/C extensions widely adopted by compilers.
  30 For detail, see:
  31
  32   http://gcc.gnu.org/onlinedocs/gcc/C-Extensions.html#C-Extensions
  33
  34
  35
  36 ** Non-standard Dependencies
  37
  38 In some cases, standards do not provide the required primitives to write
  39 portable code; these are listed here.
  40
  41
  42 * Non-standard endian.h
  43
  44 endian.h is used to provide the following definitions:
  45
  46 #define LITTLE_ENDIAN   1234
  47 #define BIG_ENDIAN      4321
  48 #define BYTE_ORDER      /* Your architecture: BIG_ENDIAN or LITTLE_ENDIAN */
  49
  50
  51 * Bitfields
  52
  53 The ISO/IEC 9899 standard leaves bitfields implementation defined, which is
  54 unacceptable for portability of this library. Section 6.7.2.1 - "Structure and
  55 union specifiers", Semantic 10 specifically indicates that padding and order of
  56 bit-fields allocation within a unit is implementation-defined.
  57
  58 This is why this library provides the bitfield.h header (under the MIT license),
  59 which specifies bitfields write primitives that uses the same field order as the
  60 GNU/C compiler, but does not require any padding for fields spreading across
  61 units. This is therefore a superset of the GNU/C bitfields, which can be dealt
  62 with by detecting C structure padding manually given the bit offset and
  63 bit-field size as well as the unit size.
  64
  65
  66 ** Libraries
  67
  68 * The GLib library of C routines
  69
  70 The library glib 2 is used for its basic data structures. See
  71
  72   http://library.gnome.org/devel/glib/2.24/glib-data-types.html