/*
* Copyright © 2011 Red Hat, Inc
*
* SPDX-License-Identifier: LGPL-2.1-or-later
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see .
*
* Author: Matthias Clasen
*/
/* This file collects documentation for macros, typedefs and
* the like, which have no good home in any of the 'real' source
* files.
*/
/* Type conversion {{{1 */
/**
* GINT_TO_POINTER:
* @i: integer to stuff into a pointer
*
* Stuffs an integer into a pointer type.
*
* Remember, you may not store pointers in integers. This is not portable
* in any way, shape or form. These macros only allow storing integers in
* pointers, and only preserve 32 bits of the integer; values outside the
* range of a 32-bit integer will be mangled.
*/
/**
* GPOINTER_TO_INT:
* @p: pointer containing an integer
*
* Extracts an integer from a pointer. The integer must have
* been stored in the pointer with GINT_TO_POINTER().
*
* Remember, you may not store pointers in integers. This is not portable
* in any way, shape or form. These macros only allow storing integers in
* pointers, and only preserve 32 bits of the integer; values outside the
* range of a 32-bit integer will be mangled.
*/
/**
* GUINT_TO_POINTER:
* @u: unsigned integer to stuff into the pointer
*
* Stuffs an unsigned integer into a pointer type.
*/
/**
* GPOINTER_TO_UINT:
* @p: pointer to extract an unsigned integer from
*
* Extracts an unsigned integer from a pointer. The integer must have
* been stored in the pointer with GUINT_TO_POINTER().
*/
/**
* GSIZE_TO_POINTER:
* @s: #gsize to stuff into the pointer
*
* Stuffs a #gsize into a pointer type.
*
* Remember, you may not store pointers in integers. This is not portable
* in any way, shape or form. These macros only allow storing integers in
* pointers, and preserve all bits of a pointer (e.g. on CHERI systems).
* The only types that can store pointers as well as integers are #guintptr
* and #gintptr.
*/
/**
* GPOINTER_TO_SIZE:
* @p: pointer to extract a #gsize from
*
* Extracts a #gsize from a pointer. The #gsize must have
* been stored in the pointer with GSIZE_TO_POINTER().
*
* Remember, you may not store pointers in integers. This is not portable
* in any way, shape or form. These macros only allow storing integers in
* pointers, and preserve all bits of a pointer (e.g. on CHERI systems).
* The only types that can store pointers as well as integers are #guintptr
* and #gintptr.
*
* See also GPOINTER_TO_TYPE() for #GType.
*/
/* Byte order {{{1 */
/**
* G_BYTE_ORDER:
*
* The host byte order.
* This can be either %G_LITTLE_ENDIAN or %G_BIG_ENDIAN (support for
* %G_PDP_ENDIAN may be added in future.)
*/
/**
* G_LITTLE_ENDIAN:
*
* Specifies one of the possible types of byte order.
* See %G_BYTE_ORDER.
*/
/**
* G_BIG_ENDIAN:
*
* Specifies one of the possible types of byte order.
* See %G_BYTE_ORDER.
*/
/**
* G_PDP_ENDIAN:
*
* Specifies one of the possible types of byte order
* (currently unused). See %G_BYTE_ORDER.
*/
/**
* g_htonl:
* @val: a 32-bit integer value in host byte order
*
* Converts a 32-bit integer value from host to network byte order.
*
* Returns: @val converted to network byte order
*/
/**
* g_htons:
* @val: a 16-bit integer value in host byte order
*
* Converts a 16-bit integer value from host to network byte order.
*
* Returns: @val converted to network byte order
*/
/**
* g_ntohl:
* @val: a 32-bit integer value in network byte order
*
* Converts a 32-bit integer value from network to host byte order.
*
* Returns: @val converted to host byte order.
*/
/**
* g_ntohs:
* @val: a 16-bit integer value in network byte order
*
* Converts a 16-bit integer value from network to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GINT_FROM_BE:
* @val: a #gint value in big-endian byte order
*
* Converts a #gint value from big-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GINT_FROM_LE:
* @val: a #gint value in little-endian byte order
*
* Converts a #gint value from little-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GINT_TO_BE:
* @val: a #gint value in host byte order
*
* Converts a #gint value from host byte order to big-endian.
*
* Returns: @val converted to big-endian byte order
*/
/**
* GINT_TO_LE:
* @val: a #gint value in host byte order
*
* Converts a #gint value from host byte order to little-endian.
*
* Returns: @val converted to little-endian byte order
*/
/**
* GUINT_FROM_BE:
* @val: a #guint value in big-endian byte order
*
* Converts a #guint value from big-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GUINT_FROM_LE:
* @val: a #guint value in little-endian byte order
*
* Converts a #guint value from little-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GUINT_TO_BE:
* @val: a #guint value in host byte order
*
* Converts a #guint value from host byte order to big-endian.
*
* Returns: @val converted to big-endian byte order
*/
/**
* GUINT_TO_LE:
* @val: a #guint value in host byte order
*
* Converts a #guint value from host byte order to little-endian.
*
* Returns: @val converted to little-endian byte order.
*/
/**
* GLONG_FROM_BE:
* @val: a #glong value in big-endian byte order
*
* Converts a #glong value from big-endian to the host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GLONG_FROM_LE:
* @val: a #glong value in little-endian byte order
*
* Converts a #glong value from little-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GLONG_TO_BE:
* @val: a #glong value in host byte order
*
* Converts a #glong value from host byte order to big-endian.
*
* Returns: @val converted to big-endian byte order
*/
/**
* GLONG_TO_LE:
* @val: a #glong value in host byte order
*
* Converts a #glong value from host byte order to little-endian.
*
* Returns: @val converted to little-endian
*/
/**
* GULONG_FROM_BE:
* @val: a #gulong value in big-endian byte order
*
* Converts a #gulong value from big-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GULONG_FROM_LE:
* @val: a #gulong value in little-endian byte order
*
* Converts a #gulong value from little-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GULONG_TO_BE:
* @val: a #gulong value in host byte order
*
* Converts a #gulong value from host byte order to big-endian.
*
* Returns: @val converted to big-endian
*/
/**
* GULONG_TO_LE:
* @val: a #gulong value in host byte order
*
* Converts a #gulong value from host byte order to little-endian.
*
* Returns: @val converted to little-endian
*/
/**
* GSIZE_FROM_BE:
* @val: a #gsize value in big-endian byte order
*
* Converts a #gsize value from big-endian to the host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GSIZE_FROM_LE:
* @val: a #gsize value in little-endian byte order
*
* Converts a #gsize value from little-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GSIZE_TO_BE:
* @val: a #gsize value in host byte order
*
* Converts a #gsize value from host byte order to big-endian.
*
* Returns: @val converted to big-endian byte order
*/
/**
* GSIZE_TO_LE:
* @val: a #gsize value in host byte order
*
* Converts a #gsize value from host byte order to little-endian.
*
* Returns: @val converted to little-endian
*/
/**
* GSSIZE_FROM_BE:
* @val: a #gssize value in big-endian byte order
*
* Converts a #gssize value from big-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GSSIZE_FROM_LE:
* @val: a #gssize value in little-endian byte order
*
* Converts a #gssize value from little-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GSSIZE_TO_BE:
* @val: a #gssize value in host byte order
*
* Converts a #gssize value from host byte order to big-endian.
*
* Returns: @val converted to big-endian
*/
/**
* GSSIZE_TO_LE:
* @val: a #gssize value in host byte order
*
* Converts a #gssize value from host byte order to little-endian.
*
* Returns: @val converted to little-endian
*/
/**
* GINT16_FROM_BE:
* @val: a #gint16 value in big-endian byte order
*
* Converts a #gint16 value from big-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GINT16_FROM_LE:
* @val: a #gint16 value in little-endian byte order
*
* Converts a #gint16 value from little-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GINT16_TO_BE:
* @val: a #gint16 value in host byte order
*
* Converts a #gint16 value from host byte order to big-endian.
*
* Returns: @val converted to big-endian
*/
/**
* GINT16_TO_LE:
* @val: a #gint16 value in host byte order
*
* Converts a #gint16 value from host byte order to little-endian.
*
* Returns: @val converted to little-endian
*/
/**
* GUINT16_FROM_BE:
* @val: a #guint16 value in big-endian byte order
*
* Converts a #guint16 value from big-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GUINT16_FROM_LE:
* @val: a #guint16 value in little-endian byte order
*
* Converts a #guint16 value from little-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GUINT16_TO_BE:
* @val: a #guint16 value in host byte order
*
* Converts a #guint16 value from host byte order to big-endian.
*
* Returns: @val converted to big-endian
*/
/**
* GUINT16_TO_LE:
* @val: a #guint16 value in host byte order
*
* Converts a #guint16 value from host byte order to little-endian.
*
* Returns: @val converted to little-endian
*/
/**
* GINT32_FROM_BE:
* @val: a #gint32 value in big-endian byte order
*
* Converts a #gint32 value from big-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GINT32_FROM_LE:
* @val: a #gint32 value in little-endian byte order
*
* Converts a #gint32 value from little-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GINT32_TO_BE:
* @val: a #gint32 value in host byte order
*
* Converts a #gint32 value from host byte order to big-endian.
*
* Returns: @val converted to big-endian
*/
/**
* GINT32_TO_LE:
* @val: a #gint32 value in host byte order
*
* Converts a #gint32 value from host byte order to little-endian.
*
* Returns: @val converted to little-endian
*/
/**
* GUINT32_FROM_BE:
* @val: a #guint32 value in big-endian byte order
*
* Converts a #guint32 value from big-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GUINT32_FROM_LE:
* @val: a #guint32 value in little-endian byte order
*
* Converts a #guint32 value from little-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GUINT32_TO_BE:
* @val: a #guint32 value in host byte order
*
* Converts a #guint32 value from host byte order to big-endian.
*
* Returns: @val converted to big-endian
*/
/**
* GUINT32_TO_LE:
* @val: a #guint32 value in host byte order
*
* Converts a #guint32 value from host byte order to little-endian.
*
* Returns: @val converted to little-endian
*/
/**
* GINT64_FROM_BE:
* @val: a #gint64 value in big-endian byte order
*
* Converts a #gint64 value from big-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GINT64_FROM_LE:
* @val: a #gint64 value in little-endian byte order
*
* Converts a #gint64 value from little-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GINT64_TO_BE:
* @val: a #gint64 value in host byte order
*
* Converts a #gint64 value from host byte order to big-endian.
*
* Returns: @val converted to big-endian
*/
/**
* GINT64_TO_LE:
* @val: a #gint64 value in host byte order
*
* Converts a #gint64 value from host byte order to little-endian.
*
* Returns: @val converted to little-endian
*/
/**
* GUINT64_FROM_BE:
* @val: a #guint64 value in big-endian byte order
*
* Converts a #guint64 value from big-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GUINT64_FROM_LE:
* @val: a #guint64 value in little-endian byte order
*
* Converts a #guint64 value from little-endian to host byte order.
*
* Returns: @val converted to host byte order
*/
/**
* GUINT64_TO_BE:
* @val: a #guint64 value in host byte order
*
* Converts a #guint64 value from host byte order to big-endian.
*
* Returns: @val converted to big-endian
*/
/**
* GUINT64_TO_LE:
* @val: a #guint64 value in host byte order
*
* Converts a #guint64 value from host byte order to little-endian.
*
* Returns: @val converted to little-endian
*/
/**
* GUINT16_SWAP_BE_PDP:
* @val: a #guint16 value in big-endian or pdp-endian byte order
*
* Converts a #guint16 value between big-endian and pdp-endian byte order.
* The conversion is symmetric so it can be used both ways.
*
* Returns: @val converted to the opposite byte order
*/
/**
* GUINT16_SWAP_LE_BE:
* @val: a #guint16 value in little-endian or big-endian byte order
*
* Converts a #guint16 value between little-endian and big-endian byte order.
* The conversion is symmetric so it can be used both ways.
*
* Returns: @val converted to the opposite byte order
*/
/**
* GUINT16_SWAP_LE_PDP:
* @val: a #guint16 value in little-endian or pdp-endian byte order
*
* Converts a #guint16 value between little-endian and pdp-endian byte order.
* The conversion is symmetric so it can be used both ways.
*
* Returns: @val converted to the opposite byte order
*/
/**
* GUINT32_SWAP_BE_PDP:
* @val: a #guint32 value in big-endian or pdp-endian byte order
*
* Converts a #guint32 value between big-endian and pdp-endian byte order.
* The conversion is symmetric so it can be used both ways.
*
* Returns: @val converted to the opposite byte order
*/
/**
* GUINT32_SWAP_LE_BE:
* @val: a #guint32 value in little-endian or big-endian byte order
*
* Converts a #guint32 value between little-endian and big-endian byte order.
* The conversion is symmetric so it can be used both ways.
*
* Returns: @val converted to the opposite byte order
*/
/**
* GUINT32_SWAP_LE_PDP:
* @val: a #guint32 value in little-endian or pdp-endian byte order
*
* Converts a #guint32 value between little-endian and pdp-endian byte order.
* The conversion is symmetric so it can be used both ways.
*
* Returns: @val converted to the opposite byte order
*/
/**
* GUINT64_SWAP_LE_BE:
* @val: a #guint64 value in little-endian or big-endian byte order
*
* Converts a #guint64 value between little-endian and big-endian byte order.
* The conversion is symmetric so it can be used both ways.
*
* Returns: @val converted to the opposite byte order
*/
/* Bounds-checked integer arithmetic {{{1 */
/**
* g_uint_checked_add
* @dest: a pointer to the #guint destination
* @a: the #guint left operand
* @b: the #guint right operand
*
* Performs a checked addition of @a and @b, storing the result in
* @dest.
*
* If the operation is successful, %TRUE is returned. If the operation
* overflows then the state of @dest is undefined and %FALSE is
* returned.
*
* Returns: %TRUE if there was no overflow
* Since: 2.48
*/
/**
* g_uint_checked_mul
* @dest: a pointer to the #guint destination
* @a: the #guint left operand
* @b: the #guint right operand
*
* Performs a checked multiplication of @a and @b, storing the result in
* @dest.
*
* If the operation is successful, %TRUE is returned. If the operation
* overflows then the state of @dest is undefined and %FALSE is
* returned.
*
* Returns: %TRUE if there was no overflow
* Since: 2.48
*/
/**
* g_uint64_checked_add
* @dest: a pointer to the #guint64 destination
* @a: the #guint64 left operand
* @b: the #guint64 right operand
*
* Performs a checked addition of @a and @b, storing the result in
* @dest.
*
* If the operation is successful, %TRUE is returned. If the operation
* overflows then the state of @dest is undefined and %FALSE is
* returned.
*
* Returns: %TRUE if there was no overflow
* Since: 2.48
*/
/**
* g_uint64_checked_mul
* @dest: a pointer to the #guint64 destination
* @a: the #guint64 left operand
* @b: the #guint64 right operand
*
* Performs a checked multiplication of @a and @b, storing the result in
* @dest.
*
* If the operation is successful, %TRUE is returned. If the operation
* overflows then the state of @dest is undefined and %FALSE is
* returned.
*
* Returns: %TRUE if there was no overflow
* Since: 2.48
*/
/**
* g_size_checked_add
* @dest: a pointer to the #gsize destination
* @a: the #gsize left operand
* @b: the #gsize right operand
*
* Performs a checked addition of @a and @b, storing the result in
* @dest.
*
* If the operation is successful, %TRUE is returned. If the operation
* overflows then the state of @dest is undefined and %FALSE is
* returned.
*
* Returns: %TRUE if there was no overflow
* Since: 2.48
*/
/**
* g_size_checked_mul
* @dest: a pointer to the #gsize destination
* @a: the #gsize left operand
* @b: the #gsize right operand
*
* Performs a checked multiplication of @a and @b, storing the result in
* @dest.
*
* If the operation is successful, %TRUE is returned. If the operation
* overflows then the state of @dest is undefined and %FALSE is
* returned.
*
* Returns: %TRUE if there was no overflow
* Since: 2.48
*/
/* Numerical Definitions {{{1 */
/**
* G_IEEE754_FLOAT_BIAS:
*
* The bias by which exponents in single-precision floats are offset.
*/
/**
* G_IEEE754_DOUBLE_BIAS:
*
* The bias by which exponents in double-precision floats are offset.
*/
/**
* GFloatIEEE754:
* @v_float: the double value
*
* The #GFloatIEEE754 and #GDoubleIEEE754 unions are used to access the sign,
* mantissa and exponent of IEEE floats and doubles. These unions are defined
* as appropriate for a given platform. IEEE floats and doubles are supported
* (used for storage) by at least Intel, PPC and Sparc.
*/
/**
* GDoubleIEEE754:
* @v_double: the double value
*
* The #GFloatIEEE754 and #GDoubleIEEE754 unions are used to access the sign,
* mantissa and exponent of IEEE floats and doubles. These unions are defined
* as appropriate for a given platform. IEEE floats and doubles are supported
* (used for storage) by at least Intel, PPC and Sparc.
*/
/**
* G_E:
*
* The base of natural logarithms.
*/
/**
* G_LN2:
*
* The natural logarithm of 2.
*/
/**
* G_LN10:
*
* The natural logarithm of 10.
*/
/**
* G_PI:
*
* The value of pi (ratio of circle's circumference to its diameter).
*/
/**
* G_PI_2:
*
* Pi divided by 2.
*/
/**
* G_PI_4:
*
* Pi divided by 4.
*/
/**
* G_SQRT2:
*
* The square root of two.
*/
/**
* G_LOG_2_BASE_10:
*
* Multiplying the base 2 exponent by this number yields the base 10 exponent.
*/
/* Macros {{{1 */
/**
* G_OS_WIN32:
*
* This macro is defined only on Windows. So you can bracket
* Windows-specific code in `#ifdef G_OS_WIN32`.
*/
/**
* G_OS_UNIX:
*
* This macro is defined only on UNIX. So you can bracket
* UNIX-specific code in `#ifdef G_OS_UNIX`.
*
* To detect whether to compile features that require a specific kernel
* or operating system, check for the appropriate OS-specific predefined
* macros instead, for example:
*
* - Linux kernel (any libc, including glibc, musl or Android): `#ifdef __linux__`
* - Linux kernel and GNU user-space: `#if defined(__linux__) && defined(__GLIBC__)`
* - FreeBSD kernel (any libc, including glibc): `#ifdef __FreeBSD_kernel__`
* - FreeBSD kernel and user-space: `#ifdef __FreeBSD__`
* - Apple operating systems (macOS, iOS, tvOS), regardless of whether
* Cocoa/Carbon toolkits are available: `#ifdef __APPLE__`
*
* See for more.
*/
/**
* G_DIR_SEPARATOR:
*
* The directory separator character.
*
* This is `'/'` on UNIX machines and `'\'` under Windows.
*/
/**
* G_DIR_SEPARATOR_S:
*
* The directory separator as a string.
*
* This is `"/"` on UNIX machines and `"\"` under Windows.
*/
/**
* G_IS_DIR_SEPARATOR:
* @c: a character
*
* Checks whether a character is a directory separator.
*
* It returns true for `'/'` on UNIX machines and for `'\'` or `'/'` under
* Windows.
*
* Since: 2.6
*/
/**
* G_SEARCHPATH_SEPARATOR:
*
* The search path separator character.
* This is ':' on UNIX machines and ';' under Windows.
*/
/**
* G_SEARCHPATH_SEPARATOR_S:
*
* The search path separator as a string.
* This is ":" on UNIX machines and ";" under Windows.
*/
/**
* TRUE:
*
* Defines the %TRUE value for the #gboolean type.
*/
/**
* FALSE:
*
* Defines the %FALSE value for the #gboolean type.
*/
/**
* NULL:
*
* Defines the standard %NULL pointer.
*/
/**
* MIN:
* @a: a numeric value
* @b: a numeric value
*
* Calculates the minimum of @a and @b.
*
* Returns: the minimum of @a and @b.
*/
/**
* MAX:
* @a: a numeric value
* @b: a numeric value
*
* Calculates the maximum of @a and @b.
*
* Returns: the maximum of @a and @b.
*/
/**
* ABS:
* @a: a numeric value
*
* Calculates the absolute value of @a.
* The absolute value is simply the number with any negative sign taken away.
*
* For example,
* - ABS(-10) is 10.
* - ABS(10) is also 10.
*
* Returns: the absolute value of @a.
*/
/**
* CLAMP:
* @x: the value to clamp
* @low: the minimum value allowed
* @high: the maximum value allowed
*
* Ensures that @x is between the limits set by @low and @high. If @low is
* greater than @high the result is undefined.
*
* For example,
* - CLAMP(5, 10, 15) is 10.
* - CLAMP(15, 5, 10) is 10.
* - CLAMP(20, 15, 25) is 20.
*
* Returns: the value of @x clamped to the range between @low and @high
*/
/**
* G_APPROX_VALUE:
* @a: a numeric value
* @b: a numeric value
* @epsilon: a numeric value that expresses the tolerance between @a and @b
*
* Evaluates to a truth value if the absolute difference between @a and @b is
* smaller than @epsilon, and to a false value otherwise.
*
* For example,
* - `G_APPROX_VALUE (5, 6, 2)` evaluates to true
* - `G_APPROX_VALUE (3.14, 3.15, 0.001)` evaluates to false
* - `G_APPROX_VALUE (n, 0.f, FLT_EPSILON)` evaluates to true if `n` is within
* the single precision floating point epsilon from zero
*
* Returns: %TRUE if the two values are within the desired range
*
* Since: 2.58
*/
/**
* G_STRUCT_MEMBER:
* @member_type: the type of the struct field
* @struct_p: a pointer to a struct
* @struct_offset: the offset of the field from the start of the struct,
* in bytes
*
* Returns a member of a structure at a given offset, using the given type.
*
* Returns: the struct member
*/
/**
* G_STRUCT_MEMBER_P:
* @struct_p: a pointer to a struct
* @struct_offset: the offset from the start of the struct, in bytes
*
* Returns an untyped pointer to a given offset of a struct.
*
* Returns: an untyped pointer to @struct_p plus @struct_offset bytes
*/
/**
* G_STRUCT_OFFSET:
* @struct_type: a structure type, e.g. #GtkWidget
* @member: a field in the structure, e.g. @window
*
* Returns the offset, in bytes, of a member of a struct.
*
* Consider using standard C `offsetof()`, available since at least C89
* and C++98, in new code (but note that `offsetof()` returns a `size_t`
* rather than a `long`).
*
* Returns: the offset of @member from the start of @struct_type,
* as a value of type #glong.
*/
/**
* G_N_ELEMENTS:
* @arr: the array
*
* Determines the number of elements in an array. The array must be
* declared so the compiler knows its size at compile-time; this
* macro will not work on an array allocated on the heap, only static
* arrays or arrays on the stack.
*/
/* Miscellaneous Macros {{{1 */
/**
* G_STMT_START:
*
* Used within multi-statement macros so that they can be used in places
* where only one statement is expected by the compiler.
*/
/**
* G_STMT_END:
*
* Used within multi-statement macros so that they can be used in places
* where only one statement is expected by the compiler.
*/
/**
* G_BEGIN_DECLS:
*
* Used (along with %G_END_DECLS) to bracket header files. If the
* compiler in use is a C++ compiler, adds extern "C"
* around the header.
*/
/**
* G_END_DECLS:
*
* Used (along with %G_BEGIN_DECLS) to bracket header files. If the
* compiler in use is a C++ compiler, adds extern "C"
* around the header.
*/
/**
* G_VA_COPY:
* @ap1: the va_list variable to place a copy of @ap2 in
* @ap2: a va_list
*
* Portable way to copy va_list variables.
*
* In order to use this function, you must include string.h yourself,
* because this macro may use memmove() and GLib does not include
* string.h for you.
*
* Each invocation of `G_VA_COPY (ap1, ap2)` must be matched with a
* corresponding `va_end (ap1)` call in the same function.
*
* This is equivalent to standard C `va_copy()`, available since C99
* and C++11, which should be preferred in new code.
*/
/**
* G_STRINGIFY:
* @macro_or_string: a macro or a string
*
* Accepts a macro or a string and converts it into a string after
* preprocessor argument expansion. For example, the following code:
*
* |[
* #define AGE 27
* const gchar *greeting = G_STRINGIFY (AGE) " today!";
* ]|
*
* is transformed by the preprocessor into (code equivalent to):
*
* |[
* const gchar *greeting = "27 today!";
* ]|
*/
/**
* G_PASTE:
* @identifier1: an identifier
* @identifier2: an identifier
*
* Yields a new preprocessor pasted identifier
* @identifier1identifier2 from its expanded
* arguments @identifier1 and @identifier2. For example,
* the following code:
* |[
* #define GET(traveller,method) G_PASTE(traveller_get_, method) (traveller)
* const gchar *name = GET (traveller, name);
* const gchar *quest = GET (traveller, quest);
* GdkColor *favourite = GET (traveller, favourite_colour);
* ]|
*
* is transformed by the preprocessor into:
* |[
* const gchar *name = traveller_get_name (traveller);
* const gchar *quest = traveller_get_quest (traveller);
* GdkColor *favourite = traveller_get_favourite_colour (traveller);
* ]|
*
* Since: 2.20
*/
/**
* G_STATIC_ASSERT:
* @expr: a constant expression
*
* The G_STATIC_ASSERT() macro lets the programmer check
* a condition at compile time, the condition needs to
* be compile time computable. The macro can be used in
* any place where a typedef is valid.
*
* A typedef is generally allowed in exactly the same places that
* a variable declaration is allowed. For this reason, you should
* not use G_STATIC_ASSERT() in the middle of blocks of code.
*
* The macro should only be used once per source code line.
*
* Since: 2.20
*/
/**
* G_STATIC_ASSERT_EXPR:
* @expr: a constant expression
*
* The G_STATIC_ASSERT_EXPR() macro lets the programmer check
* a condition at compile time. The condition needs to be
* compile time computable.
*
* Unlike G_STATIC_ASSERT(), this macro evaluates to an expression
* and, as such, can be used in the middle of other expressions.
* Its value should be ignored. This can be accomplished by placing
* it as the first argument of a comma expression.
*
* |[
* #define ADD_ONE_TO_INT(x) \
* (G_STATIC_ASSERT_EXPR(sizeof (x) == sizeof (int)), ((x) + 1))
* ]|
*
* Since: 2.30
*/
/**
* G_GNUC_EXTENSION:
*
* Expands to __extension__ when gcc is used as the compiler. This simply
* tells gcc not to warn about the following non-standard code when compiling
* with the `-pedantic` option.
*/
/**
* G_GNUC_CHECK_VERSION:
* @major: major version to check against
* @minor: minor version to check against
*
* Expands to a check for a compiler with __GNUC__ defined and a version
* greater than or equal to the major and minor numbers provided. For example,
* the following would only match on compilers such as GCC 4.8 or newer.
*
* |[
* #if G_GNUC_CHECK_VERSION(4, 8)
* #endif
* ]|
*
* Since: 2.42
*/
/**
* G_GNUC_BEGIN_IGNORE_DEPRECATIONS:
*
* Tells gcc (if it is a new enough version) to temporarily stop emitting
* warnings when functions marked with %G_GNUC_DEPRECATED or
* %G_GNUC_DEPRECATED_FOR are called. This is useful for when you have
* one deprecated function calling another one, or when you still have
* regression tests for deprecated functions.
*
* Use %G_GNUC_END_IGNORE_DEPRECATIONS to begin warning again. (If you
* are not compiling with `-Wdeprecated-declarations` then neither macro
* has any effect.)
*
* This macro can be used either inside or outside of a function body,
* but must appear on a line by itself. Both this macro and the corresponding
* %G_GNUC_END_IGNORE_DEPRECATIONS are considered statements, so they
* should not be used around branching or loop conditions; for instance,
* this use is invalid:
*
* |[
* G_GNUC_BEGIN_IGNORE_DEPRECATIONS
* if (check == some_deprecated_function ())
* G_GNUC_END_IGNORE_DEPRECATIONS
* {
* do_something ();
* }
* ]|
*
* and you should move the deprecated section outside the condition
*
* |[
*
* // Solution A
* some_data_t *res;
*
* G_GNUC_BEGIN_IGNORE_DEPRECATIONS
* res = some_deprecated_function ();
* G_GNUC_END_IGNORE_DEPRECATIONS
*
* if (check == res)
* {
* do_something ();
* }
*
* // Solution B
* G_GNUC_BEGIN_IGNORE_DEPRECATIONS
* if (check == some_deprecated_function ())
* {
* do_something ();
* }
* G_GNUC_END_IGNORE_DEPRECATIONS
* ]|
*
* |[
* static void
* test_deprecated_function (void)
* {
* G_GNUC_BEGIN_IGNORE_DEPRECATIONS
* g_assert_cmpint (my_mistake (), ==, 42);
* G_GNUC_END_IGNORE_DEPRECATIONS
* }
* ]|
*
* Since: 2.32
*/
/**
* G_GNUC_END_IGNORE_DEPRECATIONS:
*
* Undoes the effect of %G_GNUC_BEGIN_IGNORE_DEPRECATIONS, telling
* gcc to begin outputting warnings again (assuming those warnings
* had been enabled to begin with).
*
* This macro can be used either inside or outside of a function body,
* but must appear on a line by itself.
*
* Since: 2.32
*/
/**
* G_DEPRECATED:
*
* This macro is similar to %G_GNUC_DEPRECATED, and can be used to mark
* functions declarations as deprecated. Unlike %G_GNUC_DEPRECATED, it is
* meant to be portable across different compilers and must be placed
* before the function declaration.
*
* |[
* G_DEPRECATED
* int my_mistake (void);
* ]|
*
* Since: 2.32
*/
/**
* G_DEPRECATED_FOR:
* @f: the name of the function that this function was deprecated for
*
* This macro is similar to %G_GNUC_DEPRECATED_FOR, and can be used to mark
* functions declarations as deprecated. Unlike %G_GNUC_DEPRECATED_FOR, it
* is meant to be portable across different compilers and must be placed
* before the function declaration.
*
* |[
* G_DEPRECATED_FOR(my_replacement)
* int my_mistake (void);
* ]|
*
* Since: 2.32
*/
/**
* G_UNAVAILABLE:
* @maj: the major version that introduced the symbol
* @min: the minor version that introduced the symbol
*
* This macro can be used to mark a function declaration as unavailable.
* It must be placed before the function declaration. Use of a function
* that has been annotated with this macros will produce a compiler warning.
*
* Since: 2.32
*/
/**
* GLIB_DISABLE_DEPRECATION_WARNINGS:
*
* A macro that should be defined before including the glib.h header.
* If it is defined, no compiler warnings will be produced for uses
* of deprecated GLib APIs.
*/
/**
* G_GNUC_INTERNAL:
*
* This attribute can be used for marking library functions as being used
* internally to the library only, which may allow the compiler to handle
* function calls more efficiently. Note that static functions do not need
* to be marked as internal in this way. See the GNU C documentation for
* details.
*
* When using a compiler that supports the GNU C hidden visibility attribute,
* this macro expands to __attribute__((visibility("hidden"))).
* When using the Sun Studio compiler, it expands to __hidden.
*
* Note that for portability, the attribute should be placed before the
* function declaration. While GCC allows the macro after the declaration,
* Sun Studio does not.
*
* |[
* G_GNUC_INTERNAL
* void _g_log_fallback_handler (const gchar *log_domain,
* GLogLevelFlags log_level,
* const gchar *message,
* gpointer unused_data);
* ]|
*
* Since: 2.6
*/
/**
* G_C_STD_VERSION:
*
* The C standard version the code is compiling against, it's normally
* defined with the same value of `__STDC_VERSION__` for C standard
* compatible compilers, while it uses the lowest standard version
* in pure MSVC, given that in such compiler the definition depends on
* a compilation flag.
*
* This is granted to be undefined when compiling with a C++ compiler.
*
* See also: %G_C_STD_CHECK_VERSION and %G_CXX_STD_VERSION
*
* Since: 2.76
*/
/**
* G_C_STD_CHECK_VERSION:
* @version: The C version to be checked for compatibility
*
* Macro to check if the current compiler supports a specified @version
* of the C standard. Such value must be numeric and can be provided both
* in the short form for the well-known versions (e.g. `90`, `99`...) or in
* the complete form otherwise (e.g. `199000L`, `199901L`, `205503L`...).
*
* When a C++ compiler is used, the macro is defined and returns always %FALSE.
*
* This value is compared against %G_C_STD_VERSION.
*
* |[
* #if G_C_STD_CHECK_VERSION(17)
* #endif
* ]|
*
* See also: %G_CXX_STD_CHECK_VERSION
*
* Returns: %TRUE if @version is supported by the compiler, %FALSE otherwise
*
* Since: 2.76
*/
/**
* G_CXX_STD_VERSION:
*
* The C++ standard version the code is compiling against, it's defined
* with the same value of `__cplusplus` for C++ standard compatible
* compilers, while it uses `_MSVC_LANG` in MSVC, given that the
* standard definition depends on a compilation flag in such compiler.
*
* This is granted to be undefined when not compiling with a C++ compiler.
*
* See also: %G_CXX_STD_CHECK_VERSION and %G_C_STD_VERSION
*
* Since: 2.76
*/
/**
* G_CXX_STD_CHECK_VERSION:
* @version: The C++ version to be checked for compatibility
*
* Macro to check if the current compiler supports a specified @version
* of the C++ standard. Such value must be numeric and can be provided both
* in the short form for the well-known versions (e.g. `11`, `17`...) or in
* the complete form otherwise (e.g. `201103L`, `201703L`, `205503L`...).
*
* When a C compiler is used, the macro is defined and returns always %FALSE.
*
* This value is compared against %G_CXX_STD_VERSION.
*
* |[
* #if G_CXX_STD_CHECK_VERSION(20)
* #endif
* ]|
*
* See also: %G_C_STD_CHECK_VERSION
*
* Returns: %TRUE if @version is supported by the compiler, %FALSE otherwise
*
* Since: 2.76
*/
/**
* G_LIKELY:
* @expr: the expression
*
* Hints the compiler that the expression is likely to evaluate to
* a true value. The compiler may use this information for optimizations.
*
* |[
* if (G_LIKELY (random () != 1))
* g_print ("not one");
* ]|
*
* Returns: the value of @expr
*
* Since: 2.2
*/
/**
* G_UNLIKELY:
* @expr: the expression
*
* Hints the compiler that the expression is unlikely to evaluate to
* a true value. The compiler may use this information for optimizations.
*
* |[
* if (G_UNLIKELY (random () == 1))
* g_print ("a random one");
* ]|
*
* Returns: the value of @expr
*
* Since: 2.2
*/
/**
* G_STRLOC:
*
* Expands to a string identifying the current code position.
*/
/**
* G_STRFUNC:
*
* Expands to a string identifying the current function.
*
* Since: 2.4
*/
/**
* G_HAVE_GNUC_VISIBILITY:
*
* Defined to 1 if gcc-style visibility handling is supported.
*/
/* g_auto(), g_autoptr() and helpers {{{1 */
/**
* g_auto:
* @TypeName: a supported variable type
*
* Helper to declare a variable with automatic cleanup.
*
* The variable is cleaned up in a way appropriate to its type when the
* variable goes out of scope. The type must support this.
* The way to clean up the type must have been defined using one of the macros
* G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC() or G_DEFINE_AUTO_CLEANUP_FREE_FUNC().
*
* This feature is only supported on GCC and clang. This macro is not
* defined on other compilers and should not be used in programs that
* are intended to be portable to those compilers.
*
* This is meant to be used with stack-allocated structures and
* non-pointer types. For the (more commonly used) pointer version, see
* g_autoptr().
*
* This macro can be used to avoid having to do explicit cleanups of
* local variables when exiting functions. It often vastly simplifies
* handling of error conditions, removing the need for various tricks
* such as `goto out` or repeating of cleanup code. It is also helpful
* for non-error cases.
*
* Consider the following example:
*
* |[
* GVariant *
* my_func(void)
* {
* g_auto(GQueue) queue = G_QUEUE_INIT;
* g_auto(GVariantBuilder) builder;
* g_auto(GStrv) strv;
*
* g_variant_builder_init (&builder, G_VARIANT_TYPE_VARDICT);
* strv = g_strsplit("a:b:c", ":", -1);
*
* ...
*
* if (error_condition)
* return NULL;
*
* ...
*
* return g_variant_builder_end (&builder);
* }
* ]|
*
* You must initialize the variable in some way — either by use of an
* initialiser or by ensuring that an `_init` function will be called on
* it unconditionally before it goes out of scope.
*
* Since: 2.44
*/
/**
* g_autoptr:
* @TypeName: a supported variable type
*
* Helper to declare a pointer variable with automatic cleanup.
*
* The variable is cleaned up in a way appropriate to its type when the
* variable goes out of scope. The type must support this.
* The way to clean up the type must have been defined using the macro
* G_DEFINE_AUTOPTR_CLEANUP_FUNC().
*
* This feature is only supported on GCC and clang. This macro is not
* defined on other compilers and should not be used in programs that
* are intended to be portable to those compilers.
*
* This is meant to be used to declare pointers to types with cleanup
* functions. The type of the variable is a pointer to @TypeName. You
* must not add your own `*`.
*
* This macro can be used to avoid having to do explicit cleanups of
* local variables when exiting functions. It often vastly simplifies
* handling of error conditions, removing the need for various tricks
* such as `goto out` or repeating of cleanup code. It is also helpful
* for non-error cases.
*
* Consider the following example:
*
* |[
* gboolean
* check_exists(GVariant *dict)
* {
* g_autoptr(GVariant) dirname, basename = NULL;
* g_autofree gchar *path = NULL;
*
* dirname = g_variant_lookup_value (dict, "dirname", G_VARIANT_TYPE_STRING);
*
* if (dirname == NULL)
* return FALSE;
*
* basename = g_variant_lookup_value (dict, "basename", G_VARIANT_TYPE_STRING);
*
* if (basename == NULL)
* return FALSE;
*
* path = g_build_filename (g_variant_get_string (dirname, NULL),
* g_variant_get_string (basename, NULL),
* NULL);
*
* return g_access (path, R_OK) == 0;
* }
* ]|
*
* You must initialise the variable in some way — either by use of an
* initialiser or by ensuring that it is assigned to unconditionally
* before it goes out of scope.
*
* See also g_auto(), g_autofree() and g_steal_pointer().
*
* Since: 2.44
*/
/**
* g_autofree:
*
* Macro to add an attribute to pointer variable to ensure automatic
* cleanup using g_free().
*
* This macro differs from g_autoptr() in that it is an attribute supplied
* before the type name, rather than wrapping the type definition. Instead
* of using a type-specific lookup, this macro always calls g_free() directly.
*
* This means it's useful for any type that is returned from
* g_malloc().
*
* Otherwise, this macro has similar constraints as g_autoptr(): only
* supported on GCC and clang, the variable must be initialized, etc.
*
* |[
* gboolean
* operate_on_malloc_buf (void)
* {
* g_autofree guint8* membuf = NULL;
*
* membuf = g_malloc (8192);
*
* // Some computation on membuf
*
* // membuf will be automatically freed here
* return TRUE;
* }
* ]|
*
* Since: 2.44
*/
/**
* g_autolist:
* @TypeName: a supported variable type
*
* Helper to declare a list variable with automatic deep cleanup.
*
* The list is deeply freed, in a way appropriate to the specified type, when the
* variable goes out of scope. The type must support this.
*
* This feature is only supported on GCC and clang. This macro is not
* defined on other compilers and should not be used in programs that
* are intended to be portable to those compilers.
*
* This is meant to be used to declare lists of a type with a cleanup
* function. The type of the variable is a `GList *`. You
* must not add your own `*`.
*
* This macro can be used to avoid having to do explicit cleanups of
* local variables when exiting functions. It often vastly simplifies
* handling of error conditions, removing the need for various tricks
* such as `goto out` or repeating of cleanup code. It is also helpful
* for non-error cases.
*
* See also g_autoslist(), g_autoptr() and g_steal_pointer().
*
* Since: 2.56
*/
/**
* g_autoslist:
* @TypeName: a supported variable type
*
* Helper to declare a singly linked list variable with automatic deep cleanup.
*
* The list is deeply freed, in a way appropriate to the specified type, when the
* variable goes out of scope. The type must support this.
*
* This feature is only supported on GCC and clang. This macro is not
* defined on other compilers and should not be used in programs that
* are intended to be portable to those compilers.
*
* This is meant to be used to declare lists of a type with a cleanup
* function. The type of the variable is a `GSList *`. You
* must not add your own `*`.
*
* This macro can be used to avoid having to do explicit cleanups of
* local variables when exiting functions. It often vastly simplifies
* handling of error conditions, removing the need for various tricks
* such as `goto out` or repeating of cleanup code. It is also helpful
* for non-error cases.
*
* See also g_autolist(), g_autoptr() and g_steal_pointer().
*
* Since: 2.56
*/
/**
* g_autoqueue:
* @TypeName: a supported variable type
*
* Helper to declare a double-ended queue variable with automatic deep cleanup.
*
* The queue is deeply freed, in a way appropriate to the specified type, when the
* variable goes out of scope. The type must support this.
*
* This feature is only supported on GCC and clang. This macro is not
* defined on other compilers and should not be used in programs that
* are intended to be portable to those compilers.
*
* This is meant to be used to declare queues of a type with a cleanup
* function. The type of the variable is a `GQueue *`. You
* must not add your own `*`.
*
* This macro can be used to avoid having to do explicit cleanups of
* local variables when exiting functions. It often vastly simplifies
* handling of error conditions, removing the need for various tricks
* such as `goto out` or repeating of cleanup code. It is also helpful
* for non-error cases.
*
* See also g_autolist(), g_autoptr() and g_steal_pointer().
*
* Since: 2.62
*/
/**
* G_DEFINE_AUTOPTR_CLEANUP_FUNC:
* @TypeName: a type name to define a g_autoptr() cleanup function for
* @func: the cleanup function
*
* Defines the appropriate cleanup function for a pointer type.
*
* The function will not be called if the variable to be cleaned up
* contains %NULL.
*
* This will typically be the `_free()` or `_unref()` function for the given
* type.
*
* With this definition, it will be possible to use g_autoptr() with
* @TypeName.
*
* |[
* G_DEFINE_AUTOPTR_CLEANUP_FUNC(GObject, g_object_unref)
* ]|
*
* This macro should be used unconditionally; it is a no-op on compilers
* where cleanup is not supported.
*
* Since: 2.44
*/
/**
* G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC:
* @TypeName: a type name to define a g_auto() cleanup function for
* @func: the clear function
*
* Defines the appropriate cleanup function for a type.
*
* This will typically be the `_clear()` function for the given type.
*
* With this definition, it will be possible to use g_auto() with
* @TypeName.
*
* |[
* G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(GQueue, g_queue_clear)
* ]|
*
* This macro should be used unconditionally; it is a no-op on compilers
* where cleanup is not supported.
*
* Since: 2.44
*/
/**
* G_DEFINE_AUTO_CLEANUP_FREE_FUNC:
* @TypeName: a type name to define a g_auto() cleanup function for
* @func: the free function
* @none: the "none" value for the type
*
* Defines the appropriate cleanup function for a type.
*
* With this definition, it will be possible to use g_auto() with
* @TypeName.
*
* This function will be rarely used. It is used with pointer-based
* typedefs and non-pointer types where the value of the variable
* represents a resource that must be freed. Two examples are #GStrv
* and file descriptors.
*
* @none specifies the "none" value for the type in question. It is
* probably something like %NULL or `-1`. If the variable is found to
* contain this value then the free function will not be called.
*
* |[
* G_DEFINE_AUTO_CLEANUP_FREE_FUNC(GStrv, g_strfreev, NULL)
* ]|
*
* This macro should be used unconditionally; it is a no-op on compilers
* where cleanup is not supported.
*
* Since: 2.44
*/
/* Windows Compatibility Functions {{{1 */
/**
* MAXPATHLEN:
*
* Provided for UNIX emulation on Windows; equivalent to UNIX
* macro %MAXPATHLEN, which is the maximum length of a filename
* (including full path).
*/
/**
* G_WIN32_DLLMAIN_FOR_DLL_NAME:
* @static: empty or "static"
* @dll_name: the name of the (pointer to the) char array where
* the DLL name will be stored. If this is used, you must also
* include `windows.h`. If you need a more complex DLL entry
* point function, you cannot use this
*
* On Windows, this macro defines a DllMain() function that stores
* the actual DLL name that the code being compiled will be included in.
*
* On non-Windows platforms, expands to nothing.
*/
/**
* G_WIN32_HAVE_WIDECHAR_API:
*
* On Windows, this macro defines an expression which evaluates to
* %TRUE if the code is running on a version of Windows where the wide
* character versions of the Win32 API functions, and the wide character
* versions of the C library functions work. (They are always present in
* the DLLs, but don't work on Windows 9x and Me.)
*
* On non-Windows platforms, it is not defined.
*
* Since: 2.6
*/
/**
* G_WIN32_IS_NT_BASED:
*
* On Windows, this macro defines an expression which evaluates to
* %TRUE if the code is running on an NT-based Windows operating system.
*
* On non-Windows platforms, it is not defined.
*
* Since: 2.6
*/
/* Epilogue {{{1 */
/* vim: set foldmethod=marker: */