mirror of
https://gitlab.gnome.org/GNOME/glib.git
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2634 lines
65 KiB
C
2634 lines
65 KiB
C
/*
|
||
* Copyright © 2011 Red Hat, Inc
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*
|
||
* 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,
|
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* 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 <http://www.gnu.org/licenses/>.
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*
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* Author: Matthias Clasen
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*/
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/* This file collects documentation for macros, typedefs and
|
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* the like, which have no good home in any of the 'real' source
|
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* files.
|
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*/
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||
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/* Basic types {{{1 */
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||
|
||
/**
|
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* SECTION:types
|
||
* @title: Basic Types
|
||
* @short_description: standard GLib types, defined for ease-of-use
|
||
* and portability
|
||
*
|
||
* GLib defines a number of commonly used types, which can be divided
|
||
* into several groups:
|
||
* - New types which are not part of standard C (but are defined in
|
||
* various C standard library header files) — #gboolean, #gssize.
|
||
* - Integer types which are guaranteed to be the same size across
|
||
* all platforms — #gint8, #guint8, #gint16, #guint16, #gint32,
|
||
* #guint32, #gint64, #guint64.
|
||
* - Types which are easier to use than their standard C counterparts -
|
||
* #gpointer, #gconstpointer, #guchar, #guint, #gushort, #gulong.
|
||
* - Types which correspond exactly to standard C types, but are
|
||
* included for completeness — #gchar, #gint, #gshort, #glong,
|
||
* #gfloat, #gdouble.
|
||
* - Types which correspond exactly to standard C99 types, but are available
|
||
* to use even if your compiler does not support C99 — #gsize, #goffset,
|
||
* #gintptr, #guintptr.
|
||
*
|
||
* GLib also defines macros for the limits of some of the standard
|
||
* integer and floating point types, as well as macros for suitable
|
||
* printf() formats for these types.
|
||
*
|
||
* Note that depending on the platform and build configuration, the format
|
||
* macros might not be compatible with the system provided printf() function,
|
||
* because GLib might use a different printf() implementation internally.
|
||
* The format macros will always work with GLib API (like g_print()), and with
|
||
* any C99 compatible printf() implementation.
|
||
*/
|
||
|
||
/**
|
||
* gboolean:
|
||
*
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||
* A standard boolean type.
|
||
* Variables of this type should only contain the value
|
||
* %TRUE or %FALSE.
|
||
*
|
||
* Never directly compare the contents of a #gboolean variable with the values
|
||
* %TRUE or %FALSE. Use `if (condition)` to check a #gboolean is "true", instead
|
||
* of `if (condition == TRUE)`. Likewise use `if (!condition)` to check a
|
||
* #gboolean is "false".
|
||
*
|
||
* There is no validation when assigning to a #gboolean variable and so it could
|
||
* contain any value represented by a #gint. This is why the use of `if
|
||
* (condition)` is recommended. All non-zero values in C evaluate to "true".
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||
*/
|
||
|
||
/**
|
||
* gpointer:
|
||
*
|
||
* An untyped pointer.
|
||
* #gpointer looks better and is easier to use than void*.
|
||
*/
|
||
|
||
/**
|
||
* gconstpointer:
|
||
*
|
||
* An untyped pointer to constant data.
|
||
* The data pointed to should not be changed.
|
||
*
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||
* This is typically used in function prototypes to indicate
|
||
* that the data pointed to will not be altered by the function.
|
||
*/
|
||
|
||
/**
|
||
* gchar:
|
||
*
|
||
* Corresponds to the standard C char type.
|
||
*/
|
||
|
||
/**
|
||
* guchar:
|
||
*
|
||
* Corresponds to the standard C unsigned char type.
|
||
*/
|
||
|
||
/**
|
||
* gint:
|
||
*
|
||
* Corresponds to the standard C int type.
|
||
* Values of this type can range from #G_MININT to #G_MAXINT.
|
||
*/
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||
|
||
/**
|
||
* G_MININT:
|
||
*
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||
* The minimum value which can be held in a #gint.
|
||
*/
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||
|
||
/**
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||
* G_MAXINT:
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||
*
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||
* The maximum value which can be held in a #gint.
|
||
*/
|
||
|
||
/**
|
||
* guint:
|
||
*
|
||
* Corresponds to the standard C unsigned int type.
|
||
* Values of this type can range from 0 to #G_MAXUINT.
|
||
*/
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||
|
||
/**
|
||
* G_MAXUINT:
|
||
*
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||
* The maximum value which can be held in a #guint.
|
||
*/
|
||
|
||
/**
|
||
* gshort:
|
||
*
|
||
* Corresponds to the standard C short type.
|
||
* Values of this type can range from #G_MINSHORT to #G_MAXSHORT.
|
||
*/
|
||
|
||
/**
|
||
* G_MINSHORT:
|
||
*
|
||
* The minimum value which can be held in a #gshort.
|
||
*/
|
||
|
||
/**
|
||
* G_MAXSHORT:
|
||
*
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||
* The maximum value which can be held in a #gshort.
|
||
*/
|
||
|
||
/**
|
||
* gushort:
|
||
*
|
||
* Corresponds to the standard C unsigned short type.
|
||
* Values of this type can range from 0 to #G_MAXUSHORT.
|
||
*/
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||
|
||
/**
|
||
* G_MAXUSHORT:
|
||
*
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||
* The maximum value which can be held in a #gushort.
|
||
*/
|
||
|
||
/**
|
||
* glong:
|
||
*
|
||
* Corresponds to the standard C long type.
|
||
* Values of this type can range from #G_MINLONG to #G_MAXLONG.
|
||
*/
|
||
|
||
/**
|
||
* G_MINLONG:
|
||
*
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||
* The minimum value which can be held in a #glong.
|
||
*/
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||
|
||
/**
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||
* G_MAXLONG:
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||
*
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||
* The maximum value which can be held in a #glong.
|
||
*/
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||
|
||
/**
|
||
* gulong:
|
||
*
|
||
* Corresponds to the standard C unsigned long type.
|
||
* Values of this type can range from 0 to #G_MAXULONG.
|
||
*/
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||
|
||
/**
|
||
* G_MAXULONG:
|
||
*
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||
* The maximum value which can be held in a #gulong.
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||
*/
|
||
|
||
/**
|
||
* gint8:
|
||
*
|
||
* A signed integer guaranteed to be 8 bits on all platforms.
|
||
* Values of this type can range from #G_MININT8 (= -128) to
|
||
* #G_MAXINT8 (= 127).
|
||
*/
|
||
|
||
/**
|
||
* G_MAXINT8:
|
||
*
|
||
* The maximum value which can be held in a #gint8.
|
||
*
|
||
* Since: 2.4
|
||
*/
|
||
|
||
/**
|
||
* guint8:
|
||
*
|
||
* An unsigned integer guaranteed to be 8 bits on all platforms.
|
||
* Values of this type can range from 0 to #G_MAXUINT8 (= 255).
|
||
*/
|
||
|
||
/**
|
||
* G_MAXUINT8:
|
||
*
|
||
* The maximum value which can be held in a #guint8.
|
||
*
|
||
* Since: 2.4
|
||
*/
|
||
|
||
/**
|
||
* gint16:
|
||
*
|
||
* A signed integer guaranteed to be 16 bits on all platforms.
|
||
* Values of this type can range from #G_MININT16 (= -32,768) to
|
||
* #G_MAXINT16 (= 32,767).
|
||
*
|
||
* To print or scan values of this type, use
|
||
* %G_GINT16_MODIFIER and/or %G_GINT16_FORMAT.
|
||
*/
|
||
|
||
/**
|
||
* G_MAXINT16:
|
||
*
|
||
* The maximum value which can be held in a #gint16.
|
||
*
|
||
* Since: 2.4
|
||
*/
|
||
|
||
/**
|
||
* G_GINT16_MODIFIER:
|
||
*
|
||
* The platform dependent length modifier for conversion specifiers
|
||
* for scanning and printing values of type #gint16 or #guint16. It
|
||
* is a string literal, but doesn't include the percent-sign, such
|
||
* that you can add precision and length modifiers between percent-sign
|
||
* and conversion specifier and append a conversion specifier.
|
||
*
|
||
* The following example prints "0x7b";
|
||
* |[<!-- language="C" -->
|
||
* gint16 value = 123;
|
||
* g_print ("%#" G_GINT16_MODIFIER "x", value);
|
||
* ]|
|
||
*
|
||
* Since: 2.4
|
||
*/
|
||
|
||
/**
|
||
* G_GINT16_FORMAT:
|
||
*
|
||
* This is the platform dependent conversion specifier for scanning and
|
||
* printing values of type #gint16. It is a string literal, but doesn't
|
||
* include the percent-sign, such that you can add precision and length
|
||
* modifiers between percent-sign and conversion specifier.
|
||
*
|
||
* |[<!-- language="C" -->
|
||
* gint16 in;
|
||
* gint32 out;
|
||
* sscanf ("42", "%" G_GINT16_FORMAT, &in)
|
||
* out = in * 1000;
|
||
* g_print ("%" G_GINT32_FORMAT, out);
|
||
* ]|
|
||
*/
|
||
|
||
/**
|
||
* guint16:
|
||
*
|
||
* An unsigned integer guaranteed to be 16 bits on all platforms.
|
||
* Values of this type can range from 0 to #G_MAXUINT16 (= 65,535).
|
||
*
|
||
* To print or scan values of this type, use
|
||
* %G_GINT16_MODIFIER and/or %G_GUINT16_FORMAT.
|
||
*/
|
||
|
||
/**
|
||
* G_MAXUINT16:
|
||
*
|
||
* The maximum value which can be held in a #guint16.
|
||
*
|
||
* Since: 2.4
|
||
*/
|
||
|
||
/**
|
||
* G_GUINT16_FORMAT:
|
||
*
|
||
* This is the platform dependent conversion specifier for scanning
|
||
* and printing values of type #guint16. See also #G_GINT16_FORMAT
|
||
*/
|
||
|
||
/**
|
||
* gint32:
|
||
*
|
||
* A signed integer guaranteed to be 32 bits on all platforms.
|
||
* Values of this type can range from #G_MININT32 (= -2,147,483,648)
|
||
* to #G_MAXINT32 (= 2,147,483,647).
|
||
*
|
||
* To print or scan values of this type, use
|
||
* %G_GINT32_MODIFIER and/or %G_GINT32_FORMAT.
|
||
*/
|
||
|
||
/**
|
||
* G_MAXINT32:
|
||
*
|
||
* The maximum value which can be held in a #gint32.
|
||
*
|
||
* Since: 2.4
|
||
*/
|
||
|
||
/**
|
||
* G_GINT32_MODIFIER:
|
||
*
|
||
* The platform dependent length modifier for conversion specifiers
|
||
* for scanning and printing values of type #gint32 or #guint32. It
|
||
* is a string literal. See also #G_GINT16_MODIFIER.
|
||
*
|
||
* Since: 2.4
|
||
*/
|
||
|
||
/**
|
||
* G_GINT32_FORMAT:
|
||
*
|
||
* This is the platform dependent conversion specifier for scanning
|
||
* and printing values of type #gint32. See also #G_GINT16_FORMAT.
|
||
*/
|
||
|
||
/**
|
||
* guint32:
|
||
*
|
||
* An unsigned integer guaranteed to be 32 bits on all platforms.
|
||
* Values of this type can range from 0 to #G_MAXUINT32 (= 4,294,967,295).
|
||
*
|
||
* To print or scan values of this type, use
|
||
* %G_GINT32_MODIFIER and/or %G_GUINT32_FORMAT.
|
||
*/
|
||
|
||
/**
|
||
* G_MAXUINT32:
|
||
*
|
||
* The maximum value which can be held in a #guint32.
|
||
*
|
||
* Since: 2.4
|
||
*/
|
||
|
||
/**
|
||
* G_GUINT32_FORMAT:
|
||
*
|
||
* This is the platform dependent conversion specifier for scanning
|
||
* and printing values of type #guint32. See also #G_GINT16_FORMAT.
|
||
*/
|
||
|
||
/**
|
||
* gint64:
|
||
*
|
||
* A signed integer guaranteed to be 64 bits on all platforms.
|
||
* Values of this type can range from #G_MININT64
|
||
* (= -9,223,372,036,854,775,808) to #G_MAXINT64
|
||
* (= 9,223,372,036,854,775,807).
|
||
*
|
||
* To print or scan values of this type, use
|
||
* %G_GINT64_MODIFIER and/or %G_GINT64_FORMAT.
|
||
*/
|
||
|
||
/**
|
||
* G_MAXINT64:
|
||
*
|
||
* The maximum value which can be held in a #gint64.
|
||
*/
|
||
|
||
/**
|
||
* G_GINT64_MODIFIER:
|
||
*
|
||
* The platform dependent length modifier for conversion specifiers
|
||
* for scanning and printing values of type #gint64 or #guint64.
|
||
* It is a string literal.
|
||
*
|
||
* Some platforms do not support printing 64-bit integers, even
|
||
* though the types are supported. On such platforms %G_GINT64_MODIFIER
|
||
* is not defined.
|
||
*
|
||
* Since: 2.4
|
||
*/
|
||
|
||
/**
|
||
* G_GINT64_FORMAT:
|
||
*
|
||
* This is the platform dependent conversion specifier for scanning
|
||
* and printing values of type #gint64. See also #G_GINT16_FORMAT.
|
||
*
|
||
* Some platforms do not support scanning and printing 64-bit integers,
|
||
* even though the types are supported. On such platforms %G_GINT64_FORMAT
|
||
* is not defined. Note that scanf() may not support 64-bit integers, even
|
||
* if %G_GINT64_FORMAT is defined. Due to its weak error handling, scanf()
|
||
* is not recommended for parsing anyway; consider using g_ascii_strtoull()
|
||
* instead.
|
||
*/
|
||
|
||
/**
|
||
* guint64:
|
||
*
|
||
* An unsigned integer guaranteed to be 64-bits on all platforms.
|
||
* Values of this type can range from 0 to #G_MAXUINT64
|
||
* (= 18,446,744,073,709,551,615).
|
||
*
|
||
* To print or scan values of this type, use
|
||
* %G_GINT64_MODIFIER and/or %G_GUINT64_FORMAT.
|
||
*/
|
||
|
||
/**
|
||
* G_MAXUINT64:
|
||
*
|
||
* The maximum value which can be held in a #guint64.
|
||
*/
|
||
|
||
/**
|
||
* G_GUINT64_FORMAT:
|
||
*
|
||
* This is the platform dependent conversion specifier for scanning
|
||
* and printing values of type #guint64. See also #G_GINT16_FORMAT.
|
||
*
|
||
* Some platforms do not support scanning and printing 64-bit integers,
|
||
* even though the types are supported. On such platforms %G_GUINT64_FORMAT
|
||
* is not defined. Note that scanf() may not support 64-bit integers, even
|
||
* if %G_GINT64_FORMAT is defined. Due to its weak error handling, scanf()
|
||
* is not recommended for parsing anyway; consider using g_ascii_strtoull()
|
||
* instead.
|
||
*/
|
||
|
||
/**
|
||
* G_GINT64_CONSTANT:
|
||
* @val: a literal integer value, e.g. 0x1d636b02300a7aa7
|
||
*
|
||
* This macro is used to insert 64-bit integer literals
|
||
* into the source code.
|
||
*/
|
||
|
||
/**
|
||
* G_GUINT64_CONSTANT:
|
||
* @val: a literal integer value, e.g. 0x1d636b02300a7aa7U
|
||
*
|
||
* This macro is used to insert 64-bit unsigned integer
|
||
* literals into the source code.
|
||
*
|
||
* Since: 2.10
|
||
*/
|
||
|
||
/**
|
||
* gfloat:
|
||
*
|
||
* Corresponds to the standard C float type.
|
||
* Values of this type can range from -#G_MAXFLOAT to #G_MAXFLOAT.
|
||
*/
|
||
|
||
/**
|
||
* G_MINFLOAT:
|
||
*
|
||
* The minimum positive value which can be held in a #gfloat.
|
||
*
|
||
* If you are interested in the smallest value which can be held
|
||
* in a #gfloat, use -%G_MAXFLOAT.
|
||
*/
|
||
|
||
/**
|
||
* G_MAXFLOAT:
|
||
*
|
||
* The maximum value which can be held in a #gfloat.
|
||
*/
|
||
|
||
/**
|
||
* gdouble:
|
||
*
|
||
* Corresponds to the standard C double type.
|
||
* Values of this type can range from -#G_MAXDOUBLE to #G_MAXDOUBLE.
|
||
*/
|
||
|
||
/**
|
||
* G_MINDOUBLE:
|
||
*
|
||
* The minimum positive value which can be held in a #gdouble.
|
||
*
|
||
* If you are interested in the smallest value which can be held
|
||
* in a #gdouble, use -%G_MAXDOUBLE.
|
||
*/
|
||
|
||
/**
|
||
* G_MAXDOUBLE:
|
||
*
|
||
* The maximum value which can be held in a #gdouble.
|
||
*/
|
||
|
||
/**
|
||
* gsize:
|
||
*
|
||
* An unsigned integer type of the result of the sizeof operator,
|
||
* corresponding to the size_t type defined in C99.
|
||
* This type is wide enough to hold the numeric value of a pointer,
|
||
* so it is usually 32 bit wide on a 32-bit platform and 64 bit wide
|
||
* on a 64-bit platform. Values of this type can range from 0 to
|
||
* #G_MAXSIZE.
|
||
*
|
||
* To print or scan values of this type, use
|
||
* %G_GSIZE_MODIFIER and/or %G_GSIZE_FORMAT.
|
||
*/
|
||
|
||
/**
|
||
* G_MAXSIZE:
|
||
*
|
||
* The maximum value which can be held in a #gsize.
|
||
*
|
||
* Since: 2.4
|
||
*/
|
||
|
||
/**
|
||
* G_GSIZE_MODIFIER:
|
||
*
|
||
* The platform dependent length modifier for conversion specifiers
|
||
* for scanning and printing values of type #gsize. It
|
||
* is a string literal.
|
||
*
|
||
* Since: 2.6
|
||
*/
|
||
|
||
/**
|
||
* G_GSIZE_FORMAT:
|
||
*
|
||
* This is the platform dependent conversion specifier for scanning
|
||
* and printing values of type #gsize. See also #G_GINT16_FORMAT.
|
||
*
|
||
* Since: 2.6
|
||
*/
|
||
|
||
/**
|
||
* gssize:
|
||
*
|
||
* A signed variant of #gsize, corresponding to the
|
||
* ssize_t defined on most platforms.
|
||
* Values of this type can range from #G_MINSSIZE
|
||
* to #G_MAXSSIZE.
|
||
*
|
||
* To print or scan values of this type, use
|
||
* %G_GSSIZE_MODIFIER and/or %G_GSSIZE_FORMAT.
|
||
*/
|
||
|
||
/**
|
||
* G_MINSSIZE:
|
||
*
|
||
* The minimum value which can be held in a #gssize.
|
||
*
|
||
* Since: 2.14
|
||
*/
|
||
|
||
/**
|
||
* G_MAXSSIZE:
|
||
*
|
||
* The maximum value which can be held in a #gssize.
|
||
*
|
||
* Since: 2.14
|
||
*/
|
||
|
||
/**
|
||
* G_GSSIZE_FORMAT:
|
||
*
|
||
* This is the platform dependent conversion specifier for scanning
|
||
* and printing values of type #gssize. See also #G_GINT16_FORMAT.
|
||
*
|
||
* Since: 2.6
|
||
*/
|
||
|
||
/**
|
||
* G_GSSIZE_MODIFIER:
|
||
*
|
||
* The platform dependent length modifier for conversion specifiers
|
||
* for scanning and printing values of type #gssize. It
|
||
* is a string literal.
|
||
*
|
||
* Since: 2.6
|
||
*/
|
||
|
||
/**
|
||
* goffset:
|
||
*
|
||
* A signed integer type that is used for file offsets,
|
||
* corresponding to the POSIX type `off_t` as if compiling with
|
||
* `_FILE_OFFSET_BITS` set to 64. #goffset is always 64 bits wide, even on
|
||
* 32-bit architectures.
|
||
* Values of this type can range from #G_MINOFFSET to
|
||
* #G_MAXOFFSET.
|
||
*
|
||
* To print or scan values of this type, use
|
||
* %G_GOFFSET_MODIFIER and/or %G_GOFFSET_FORMAT.
|
||
*
|
||
* Since: 2.14
|
||
*/
|
||
|
||
/**
|
||
* G_MINOFFSET:
|
||
*
|
||
* The minimum value which can be held in a #goffset.
|
||
*/
|
||
|
||
/**
|
||
* G_MAXOFFSET:
|
||
*
|
||
* The maximum value which can be held in a #goffset.
|
||
*/
|
||
|
||
/**
|
||
* G_GOFFSET_MODIFIER:
|
||
*
|
||
* The platform dependent length modifier for conversion specifiers
|
||
* for scanning and printing values of type #goffset. It is a string
|
||
* literal. See also #G_GINT64_MODIFIER.
|
||
*
|
||
* Since: 2.20
|
||
*/
|
||
|
||
/**
|
||
* G_GOFFSET_FORMAT:
|
||
*
|
||
* This is the platform dependent conversion specifier for scanning
|
||
* and printing values of type #goffset. See also #G_GINT64_FORMAT.
|
||
*
|
||
* Since: 2.20
|
||
*/
|
||
|
||
/**
|
||
* G_GOFFSET_CONSTANT:
|
||
* @val: a literal integer value, e.g. 0x1d636b02300a7aa7
|
||
*
|
||
* This macro is used to insert #goffset 64-bit integer literals
|
||
* into the source code.
|
||
*
|
||
* See also #G_GINT64_CONSTANT.
|
||
*
|
||
* Since: 2.20
|
||
*/
|
||
|
||
/**
|
||
* gintptr:
|
||
*
|
||
* Corresponds to the C99 type intptr_t,
|
||
* a signed integer type that can hold any pointer.
|
||
*
|
||
* To print or scan values of this type, use
|
||
* %G_GINTPTR_MODIFIER and/or %G_GINTPTR_FORMAT.
|
||
*
|
||
* Since: 2.18
|
||
*/
|
||
|
||
/**
|
||
* G_GINTPTR_MODIFIER:
|
||
*
|
||
* The platform dependent length modifier for conversion specifiers
|
||
* for scanning and printing values of type #gintptr or #guintptr.
|
||
* It is a string literal.
|
||
*
|
||
* Since: 2.22
|
||
*/
|
||
|
||
/**
|
||
* G_GINTPTR_FORMAT:
|
||
*
|
||
* This is the platform dependent conversion specifier for scanning
|
||
* and printing values of type #gintptr.
|
||
*
|
||
* Since: 2.22
|
||
*/
|
||
|
||
/**
|
||
* guintptr:
|
||
*
|
||
* Corresponds to the C99 type uintptr_t,
|
||
* an unsigned integer type that can hold any pointer.
|
||
*
|
||
* To print or scan values of this type, use
|
||
* %G_GINTPTR_MODIFIER and/or %G_GUINTPTR_FORMAT.
|
||
*
|
||
* Since: 2.18
|
||
*/
|
||
|
||
/**
|
||
* G_GUINTPTR_FORMAT:
|
||
*
|
||
* This is the platform dependent conversion specifier
|
||
* for scanning and printing values of type #guintptr.
|
||
*
|
||
* Since: 2.22
|
||
*/
|
||
|
||
/* Type conversion {{{1 */
|
||
|
||
/**
|
||
* SECTION:type_conversion
|
||
* @title: Type Conversion Macros
|
||
* @short_description: portably storing integers in pointer variables
|
||
*
|
||
* Many times GLib, GTK+, and other libraries allow you to pass "user
|
||
* data" to a callback, in the form of a void pointer. From time to time
|
||
* you want to pass an integer instead of a pointer. You could allocate
|
||
* an integer, with something like:
|
||
* |[<!-- language="C" -->
|
||
* int *ip = g_new (int, 1);
|
||
* *ip = 42;
|
||
* ]|
|
||
* But this is inconvenient, and it's annoying to have to free the
|
||
* memory at some later time.
|
||
*
|
||
* Pointers are always at least 32 bits in size (on all platforms GLib
|
||
* intends to support). Thus you can store at least 32-bit integer values
|
||
* in a pointer value. Naively, you might try this, but it's incorrect:
|
||
* |[<!-- language="C" -->
|
||
* gpointer p;
|
||
* int i;
|
||
* p = (void*) 42;
|
||
* i = (int) p;
|
||
* ]|
|
||
* Again, that example was not correct, don't copy it.
|
||
* The problem is that on some systems you need to do this:
|
||
* |[<!-- language="C" -->
|
||
* gpointer p;
|
||
* int i;
|
||
* p = (void*) (long) 42;
|
||
* i = (int) (long) p;
|
||
* ]|
|
||
* The GLib macros GPOINTER_TO_INT(), GINT_TO_POINTER(), etc. take care
|
||
* to do the right thing on every platform.
|
||
*
|
||
* Warning: 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.
|
||
*/
|
||
|
||
/**
|
||
* 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.
|
||
*/
|
||
|
||
/**
|
||
* 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().
|
||
*/
|
||
|
||
/* Byte order {{{1 */
|
||
|
||
/**
|
||
* SECTION:byte_order
|
||
* @title: Byte Order Macros
|
||
* @short_description: a portable way to convert between different byte orders
|
||
*
|
||
* These macros provide a portable way to determine the host byte order
|
||
* and to convert values between different byte orders.
|
||
*
|
||
* The byte order is the order in which bytes are stored to create larger
|
||
* data types such as the #gint and #glong values.
|
||
* The host byte order is the byte order used on the current machine.
|
||
*
|
||
* Some processors store the most significant bytes (i.e. the bytes that
|
||
* hold the largest part of the value) first. These are known as big-endian
|
||
* processors. Other processors (notably the x86 family) store the most
|
||
* significant byte last. These are known as little-endian processors.
|
||
*
|
||
* Finally, to complicate matters, some other processors store the bytes in
|
||
* a rather curious order known as PDP-endian. For a 4-byte word, the 3rd
|
||
* most significant byte is stored first, then the 4th, then the 1st and
|
||
* finally the 2nd.
|
||
*
|
||
* Obviously there is a problem when these different processors communicate
|
||
* with each other, for example over networks or by using binary file formats.
|
||
* This is where these macros come in. They are typically used to convert
|
||
* values into a byte order which has been agreed on for use when
|
||
* communicating between different processors. The Internet uses what is
|
||
* known as 'network byte order' as the standard byte order (which is in
|
||
* fact the big-endian byte order).
|
||
*
|
||
* Note that the byte order conversion macros may evaluate their arguments
|
||
* multiple times, thus you should not use them with arguments which have
|
||
* side-effects.
|
||
*/
|
||
|
||
/**
|
||
* 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 */
|
||
/**
|
||
* SECTION:checkedmath
|
||
* @title: Bounds-checking integer arithmetic
|
||
* @short_description: a set of helpers for performing checked integer arithmetic
|
||
*
|
||
* GLib offers a set of macros for doing additions and multiplications
|
||
* of unsigned integers, with checks for overflows.
|
||
*
|
||
* The helpers all have three arguments. A pointer to the destination
|
||
* is always the first argument and the operands to the operation are
|
||
* the other two.
|
||
*
|
||
* Following standard GLib convention, the helpers return %TRUE in case
|
||
* of success (ie: no overflow).
|
||
*
|
||
* The helpers may be macros, normal functions or inlines. They may be
|
||
* implemented with inline assembly or compiler intrinsics where
|
||
* available.
|
||
*
|
||
* Since: 2.48
|
||
*/
|
||
|
||
/**
|
||
* 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 */
|
||
|
||
/**
|
||
* SECTION:numerical
|
||
* @title: Numerical Definitions
|
||
* @short_description: mathematical constants, and floating point decomposition
|
||
*
|
||
* GLib offers mathematical constants such as #G_PI for the value of pi;
|
||
* many platforms have these in the C library, but some don't, the GLib
|
||
* versions always exist.
|
||
*
|
||
* 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. See
|
||
* [IEEE 754-2008](http://en.wikipedia.org/wiki/IEEE_float)
|
||
* for more information about IEEE number formats.
|
||
*/
|
||
|
||
/**
|
||
* 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 */
|
||
|
||
/**
|
||
* SECTION:macros
|
||
* @title: Standard Macros
|
||
* @short_description: commonly-used macros
|
||
*
|
||
* These macros provide a few commonly-used features.
|
||
*/
|
||
|
||
/**
|
||
* 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".
|
||
*/
|
||
|
||
/**
|
||
* 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.
|
||
*
|
||
* Returns: the offset of @member from the start of @struct_type
|
||
*/
|
||
|
||
/**
|
||
* 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 */
|
||
|
||
/**
|
||
* SECTION:macros_misc
|
||
* @title: Miscellaneous Macros
|
||
* @short_description: specialized macros which are not used often
|
||
*
|
||
* These macros provide more specialized features which are not
|
||
* needed so often by application programmers.
|
||
*/
|
||
|
||
/**
|
||
* 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.
|
||
*/
|
||
|
||
/**
|
||
* 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:
|
||
*
|
||
* |[<!-- language="C" -->
|
||
* #define AGE 27
|
||
* const gchar *greeting = G_STRINGIFY (AGE) " today!";
|
||
* ]|
|
||
*
|
||
* is transformed by the preprocessor into (code equivalent to):
|
||
*
|
||
* |[<!-- language="C" -->
|
||
* 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:
|
||
* |[<!-- language="C" -->
|
||
* #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:
|
||
* |[<!-- language="C" -->
|
||
* 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.
|
||
*
|
||
* |[<!-- language="C" -->
|
||
* #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.
|
||
*
|
||
* |[<!-- language="C" -->
|
||
* #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:
|
||
*
|
||
* |[<!-- language="C" -->
|
||
* 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
|
||
*
|
||
* |[<!-- language="C" -->
|
||
*
|
||
* // 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
|
||
* ]|
|
||
*
|
||
* |[<!-- language="C" --
|
||
* 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.
|
||
*
|
||
* |[<!-- language="C" --
|
||
* 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.
|
||
*
|
||
* |[<!-- language="C" --
|
||
* 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.
|
||
*
|
||
* |[<!-- language="C" -->
|
||
* 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_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.
|
||
*
|
||
* |[<!-- language="C" -->
|
||
* 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.
|
||
*
|
||
* |[<!-- language="C" -->
|
||
* 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
|
||
*/
|
||
|
||
/* Warnings and Assertions {{{1 */
|
||
|
||
/**
|
||
* SECTION:warnings
|
||
* @title: Warnings and Assertions
|
||
* @short_description: warnings and assertions to use in runtime code
|
||
*
|
||
* GLib defines several warning functions and assertions which can be used to
|
||
* warn of programmer errors when calling functions, and print error messages
|
||
* from command line programs.
|
||
*
|
||
* The g_return_if_fail(), g_return_val_if_fail(), g_return_if_reached() and
|
||
* g_return_val_if_reached() macros are intended as pre-condition assertions, to
|
||
* be used at the top of a public function to check that the function’s
|
||
* arguments are acceptable. Any failure of such a pre-condition assertion is
|
||
* considered a programming error on the part of the caller of the public API,
|
||
* and the program is considered to be in an undefined state afterwards. They
|
||
* are similar to the libc assert() function, but provide more context on
|
||
* failures.
|
||
*
|
||
* For example:
|
||
* |[<!-- language="C" -->
|
||
* gboolean
|
||
* g_dtls_connection_shutdown (GDtlsConnection *conn,
|
||
* gboolean shutdown_read,
|
||
* gboolean shutdown_write,
|
||
* GCancellable *cancellable,
|
||
* GError **error)
|
||
* {
|
||
* // local variable declarations
|
||
*
|
||
* g_return_val_if_fail (G_IS_DTLS_CONNECTION (conn), FALSE);
|
||
* g_return_val_if_fail (cancellable == NULL || G_IS_CANCELLABLE (cancellable), FALSE);
|
||
* g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
|
||
*
|
||
* // function body
|
||
*
|
||
* return return_val;
|
||
* }
|
||
* ]|
|
||
*
|
||
* g_print(), g_printerr() and g_set_print_handler() are intended to be used for
|
||
* output from command line applications, since they output to standard output
|
||
* and standard error by default — whereas functions like g_message() and
|
||
* g_log() may be redirected to special purpose message windows, files, or the
|
||
* system journal.
|
||
*/
|
||
|
||
/* Windows Compatibility Functions {{{1 */
|
||
|
||
/**
|
||
* SECTION:windows
|
||
* @title: Windows Compatibility Functions
|
||
* @short_description: UNIX emulation on Windows
|
||
*
|
||
* These functions provide some level of UNIX emulation on the
|
||
* Windows platform. If your application really needs the POSIX
|
||
* APIs, we suggest you try the Cygwin project.
|
||
*/
|
||
|
||
/**
|
||
* 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: */
|