include/libc-internal.h

   1 /* This file contains a number of internal prototype declarations that
   2    don't fit anywhere else.  */
   3
   4 #ifndef _LIBC_INTERNAL
   5 # define _LIBC_INTERNAL 1
   6
   7 #include <hp-timing.h>
   8
   9 /* Initialize the `__libc_enable_secure' flag.  */
  10 extern void __libc_init_secure (void);
  11
  12 /* This function will be called from _init in init-first.c.  */
  13 extern void __libc_global_ctors (void);
  14
  15 /* Discover the tick frequency of the machine if something goes wrong,
  16    we return 0, an impossible hertz.  */
  17 extern int __profile_frequency (void);
  18 libc_hidden_proto (__profile_frequency)
  19
  20 /* Hooks for the instrumenting functions.  */
  21 extern void __cyg_profile_func_enter (void *this_fn, void *call_site);
  22 extern void __cyg_profile_func_exit (void *this_fn, void *call_site);
  23
  24 /* Get frequency of the system processor.  */
  25 extern hp_timing_t __get_clockfreq (void);
  26
  27 /* Free all allocated resources.  */
  28 extern void __libc_freeres (void);
  29 libc_hidden_proto (__libc_freeres)
  30
  31 /* Free resources stored in thread-local variables on thread exit.  */
  32 extern void __libc_thread_freeres (void);
  33
  34 /* Define and initialize `__progname' et. al.  */
  35 extern void __init_misc (int, char **, char **);
  36
  37 /* 1 if 'type' is a pointer type, 0 otherwise.  */
  38 # define __pointer_type(type) (__builtin_classify_type ((type) 0) == 5)
  39
  40 /* __intptr_t if P is true, or T if P is false.  */
  41 # define __integer_if_pointer_type_sub(T, P) \
  42   __typeof__ (*(0 ? (__typeof__ (0 ? (T *) 0 : (void *) (P))) 0 \
  43                   : (__typeof__ (0 ? (__intptr_t *) 0 : (void *) (!(P)))) 0))
  44
  45 /* __intptr_t if EXPR has a pointer type, or the type of EXPR otherwise.  */
  46 # define __integer_if_pointer_type(expr) \
  47   __integer_if_pointer_type_sub(__typeof__ ((__typeof__ (expr)) 0), \
  48                                 __pointer_type (__typeof__ (expr)))
  49
  50 /* Cast an integer or a pointer VAL to integer with proper type.  */
  51 # define cast_to_integer(val) ((__integer_if_pointer_type (val)) (val))
  52
  53 /* Align a value by rounding down to closest size.
  54    e.g. Using size of 4096, we get this behavior:
  55         {4095, 4096, 4097} = {0, 4096, 4096}.  */
  56 #define ALIGN_DOWN(base, size)  ((base) & -((__typeof__ (base)) (size)))
  57
  58 /* Align a value by rounding up to closest size.
  59    e.g. Using size of 4096, we get this behavior:
  60         {4095, 4096, 4097} = {4096, 4096, 8192}.
  61
  62   Note: The size argument has side effects (expanded multiple times).  */
  63 #define ALIGN_UP(base, size)    ALIGN_DOWN ((base) + (size) - 1, (size))
  64
  65 /* Same as ALIGN_DOWN(), but automatically casts when base is a pointer.  */
  66 #define PTR_ALIGN_DOWN(base, size) \
  67   ((__typeof__ (base)) ALIGN_DOWN ((uintptr_t) (base), (size)))
  68
  69 /* Same as ALIGN_UP(), but automatically casts when base is a pointer.  */
  70 #define PTR_ALIGN_UP(base, size) \
  71   ((__typeof__ (base)) ALIGN_UP ((uintptr_t) (base), (size)))
  72
  73 /* Ignore the value of an expression when a cast to void does not
  74    suffice (in particular, for a call to a function declared with
  75    attribute warn_unused_result).  */
  76 #define ignore_value(x) \
  77   ({ __typeof__ (x) __ignored_value = (x); (void) __ignored_value; })
  78
  79 /* The macros to control diagnostics are structured like this, rather
  80    than a single macro that both pushes and pops diagnostic state and
  81    takes the affected code as an argument, because the GCC pragmas
  82    work by disabling the diagnostic for a range of source locations
  83    and do not work when all the pragmas and the affected code are in a
  84    single macro expansion.  */
  85
  86 /* Push diagnostic state.  */
  87 #define DIAG_PUSH_NEEDS_COMMENT _Pragma ("GCC diagnostic push")
  88
  89 /* Pop diagnostic state.  */
  90 #define DIAG_POP_NEEDS_COMMENT _Pragma ("GCC diagnostic pop")
  91
  92 #define _DIAG_STR1(s) #s
  93 #define _DIAG_STR(s) _DIAG_STR1(s)
  94
  95 /* Ignore the diagnostic OPTION.  VERSION is the most recent GCC
  96    version for which the diagnostic has been confirmed to appear in
  97    the absence of the pragma (in the form MAJOR.MINOR for GCC 4.x,
  98    just MAJOR for GCC 5 and later).  Uses of this pragma should be
  99    reviewed when the GCC version given is no longer supported for
 100    building glibc; the version number should always be on the same
 101    source line as the macro name, so such uses can be found with grep.
 102    Uses should come with a comment giving more details of the
 103    diagnostic, and an architecture on which it is seen if possibly
 104    optimization-related and not in architecture-specific code.  This
 105    macro should only be used if the diagnostic seems hard to fix (for
 106    example, optimization-related false positives).  */
 107 #define DIAG_IGNORE_NEEDS_COMMENT(version, option)      \
 108   _Pragma (_DIAG_STR (GCC diagnostic ignored option))
 109
 110 /* This mirrors the C11 max_align_t type provided by GCC, but it is
 111    also available in C99 mode.  The aligned attributes are required
 112    because some ABIs have reduced alignment requirements for struct
 113    and union members.  */
 114 typedef struct {
 115   long long ll __attribute__ ((__aligned__ (__alignof__ (long long))));
 116   long double ld __attribute__ ((__aligned__ (__alignof__ (long double))));
 117 } libc_max_align_t;
 118
 119 #endif /* _LIBC_INTERNAL  */