luc14n0/glib
1
0
Fork 0
mirror of https://gitlab.gnome.org/GNOME/glib.git synced 2025-08-02 23:43:39 +02:00
Code Issues Packages Projects Releases Wiki Activity

grand: formatting cleanups

Browse Source
This commit is contained in:
Matthias Clasen
2014-02-01 20:50:57 -05:00
parent 3bbd15383f
commit 71d842674f
1 changed files with 120 additions and 102 deletions
Download Patch File Download Diff File Expand all files Collapse all files

222
glib/grand.c
View File

@@ -84,12 +84,13 @@
* *
* If you just need a random number, you simply call the g_random_* * If you just need a random number, you simply call the g_random_*
* functions, which will create a globally used #GRand and use the * functions, which will create a globally used #GRand and use the
* according g_rand_* functions internally. Whenever you * according g_rand_* functions internally. Whenever you need a
* need a stream of reproducible random numbers, you better create a * stream of reproducible random numbers, you better create a
* #GRand yourself and use the g_rand_* functions directly, which will * #GRand yourself and use the g_rand_* functions directly, which
* also be slightly faster. Initializing a #GRand with a certain seed * will also be slightly faster. Initializing a #GRand with a
* will produce exactly the same series of random numbers on all * certain seed will produce exactly the same series of random
* platforms. This can thus be used as a seed for e.g. games. * numbers on all platforms. This can thus be used as a seed for
* e.g. games.
* *
* The g_rand*_range functions will return high quality equally * The g_rand*_range functions will return high quality equally
* distributed random numbers, whereas for example the * distributed random numbers, whereas for example the
@@ -97,23 +98,24 @@
* doesn't yield equally distributed numbers. * doesn't yield equally distributed numbers.
* *
* GLib changed the seeding algorithm for the pseudo-random number * GLib changed the seeding algorithm for the pseudo-random number
* generator Mersenne Twister, as used by #GRand and #GRandom. * generator Mersenne Twister, as used by #GRand. This was necessary,
* This was necessary, because some seeds would yield very bad * because some seeds would yield very bad pseudo-random streams.
* pseudo-random streams. Also the pseudo-random integers generated * Also the pseudo-random integers generated by g_rand*_int_range()
* by g_rand*_int_range() will have a slightly better equal * will have a slightly better equal distribution with the new
* distribution with the new version of GLib. * version of GLib.
* *
* The original seeding and generation algorithms, as found in GLib * The original seeding and generation algorithms, as found in
* 2.0.x, can be used instead of the new ones by setting the * GLib 2.0.x, can be used instead of the new ones by setting the
* environment variable <envar>G_RANDOM_VERSION</envar> to the value of * environment variable <envar>G_RANDOM_VERSION</envar> to the value
* '2.0'. Use the GLib-2.0 algorithms only if you have sequences of * of '2.0'. Use the GLib-2.0 algorithms only if you have sequences
* numbers generated with Glib-2.0 that you need to reproduce exactly. * of numbers generated with Glib-2.0 that you need to reproduce
**/ * exactly.
*/
/** /**
* GRand: * GRand:
* *
* The #GRand struct is an opaque data structure. It should only be * The GRand struct is an opaque data structure. It should only be
* accessed through the g_rand_* functions. * accessed through the g_rand_* functions.
**/ **/
@@ -168,11 +170,11 @@ struct _GRand
/** /**
* g_rand_new_with_seed: * g_rand_new_with_seed:
* @seed: a value to initialize the random number generator. * @seed: a value to initialize the random number generator
* *
* Creates a new random number generator initialized with @seed. * Creates a new random number generator initialized with @seed.
* *
* Return value: the new #GRand. * Return value: the new #GRand
**/ **/
GRand* GRand*
g_rand_new_with_seed (guint32 seed) g_rand_new_with_seed (guint32 seed)
@@ -184,17 +186,19 @@ g_rand_new_with_seed (guint32 seed)
/** /**
* g_rand_new_with_seed_array: * g_rand_new_with_seed_array:
* @seed: an array of seeds to initialize the random number generator. * @seed: an array of seeds to initialize the random number generator
* @seed_length: an array of seeds to initialize the random number generator. * @seed_length: an array of seeds to initialize the random number
* generator
* *
* Creates a new random number generator initialized with @seed. * Creates a new random number generator initialized with @seed.
* *
* Return value: the new #GRand. * Return value: the new #GRand
* *
* Since: 2.4 * Since: 2.4
**/ */
GRand* GRand*
g_rand_new_with_seed_array (const guint32 *seed, guint seed_length) g_rand_new_with_seed_array (const guint32 *seed,
guint seed_length)
{ {
GRand *rand = g_new0 (GRand, 1); GRand *rand = g_new0 (GRand, 1);
g_rand_set_seed_array (rand, seed, seed_length); g_rand_set_seed_array (rand, seed, seed_length);
@@ -206,11 +210,12 @@ g_rand_new_with_seed_array (const guint32 *seed, guint seed_length)
* *
* Creates a new random number generator initialized with a seed taken * Creates a new random number generator initialized with a seed taken
* either from <filename>/dev/urandom</filename> (if existing) or from * either from <filename>/dev/urandom</filename> (if existing) or from
* the current time (as a fallback). On Windows, the seed is taken from * the current time (as a fallback).
* rand_s(). *
* On Windows, the seed is taken from rand_s().
* *
* Return value: the new #GRand. * Return value: the new #GRand
**/ */
GRand* GRand*
g_rand_new (void) g_rand_new (void)
{ {
@@ -270,12 +275,12 @@ g_rand_new (void)
/** /**
* g_rand_free: * g_rand_free:
* @rand_: a #GRand. * @rand_: a #GRand
* *
* Frees the memory allocated for the #GRand. * Frees the memory allocated for the #GRand.
**/ */
void void
g_rand_free (GRand* rand) g_rand_free (GRand *rand)
{ {
g_return_if_fail (rand != NULL); g_return_if_fail (rand != NULL);
@@ -284,18 +289,18 @@ g_rand_free (GRand* rand)
/** /**
* g_rand_copy: * g_rand_copy:
* @rand_: a #GRand. * @rand_: a #GRand
* *
* Copies a #GRand into a new one with the same exact state as before. * Copies a #GRand into a new one with the same exact state as before.
* This way you can take a snapshot of the random number generator for * This way you can take a snapshot of the random number generator for
* replaying later. * replaying later.
* *
* Return value: the new #GRand. * Return value: the new #GRand
* *
* Since: 2.4 * Since: 2.4
**/ */
GRand * GRand*
g_rand_copy (GRand* rand) g_rand_copy (GRand *rand)
{ {
GRand* new_rand; GRand* new_rand;
@@ -309,13 +314,14 @@ g_rand_copy (GRand* rand)
/** /**
* g_rand_set_seed: * g_rand_set_seed:
* @rand_: a #GRand. * @rand_: a #GRand
* @seed: a value to reinitialize the random number generator. * @seed: a value to reinitialize the random number generator
* *
* Sets the seed for the random number generator #GRand to @seed. * Sets the seed for the random number generator #GRand to @seed.
**/ */
void void
g_rand_set_seed (GRand* rand, guint32 seed) g_rand_set_seed (GRand *rand,
guint32 seed)
{ {
g_return_if_fail (rand != NULL); g_return_if_fail (rand != NULL);
@@ -352,20 +358,22 @@ g_rand_set_seed (GRand* rand, guint32 seed)
/** /**
* g_rand_set_seed_array: * g_rand_set_seed_array:
* @rand_: a #GRand. * @rand_: a #GRand
* @seed: array to initialize with * @seed: array to initialize with
* @seed_length: length of array * @seed_length: length of array
* *
* Initializes the random number generator by an array of longs. * Initializes the random number generator by an array of longs.
* Array can be of arbitrary size, though only the * Array can be of arbitrary size, though only the first 624 values
* first 624 values are taken. This function is useful * are taken. This function is useful if you have many low entropy
* if you have many low entropy seeds, or if you require more then * seeds, or if you require more then 32 bits of actual entropy for
* 32 bits of actual entropy for your application. * your application.
* *
* Since: 2.4 * Since: 2.4
**/ */
void void
g_rand_set_seed_array (GRand* rand, const guint32 *seed, guint seed_length) g_rand_set_seed_array (GRand *rand,
const guint32 *seed,
guint seed_length)
{ {
int i, j, k; int i, j, k;
@@ -410,24 +418,24 @@ g_rand_set_seed_array (GRand* rand, const guint32 *seed, guint seed_length)
/** /**
* g_rand_boolean: * g_rand_boolean:
* @rand_: a #GRand. * @rand_: a #GRand
* *
* Returns a random #gboolean from @rand_. This corresponds to a * Returns a random #gboolean from @rand_.
* unbiased coin toss. * This corresponds to a unbiased coin toss.
* *
* Returns: a random #gboolean. * Returns: a random #gboolean
**/ */
/** /**
* g_rand_int: * g_rand_int:
* @rand_: a #GRand. * @rand_: a #GRand
* *
* Returns the next random #guint32 from @rand_ equally distributed over * Returns the next random #guint32 from @rand_ equally distributed over
* the range [0..2^32-1]. * the range [0..2^32-1].
* *
* Return value: A random number. * Return value: a random number
**/ */
guint32 guint32
g_rand_int (GRand* rand) g_rand_int (GRand *rand)
{ {
guint32 y; guint32 y;
static const guint32 mag01[2]={0x0, MATRIX_A}; static const guint32 mag01[2]={0x0, MATRIX_A};
@@ -438,11 +446,11 @@ g_rand_int (GRand* rand)
if (rand->mti >= N) { /* generate N words at one time */ if (rand->mti >= N) { /* generate N words at one time */
int kk; int kk;
for (kk=0;kk<N-M;kk++) { for (kk = 0; kk < N - M; kk++) {
y = (rand->mt[kk]&UPPER_MASK)|(rand->mt[kk+1]&LOWER_MASK); y = (rand->mt[kk]&UPPER_MASK)|(rand->mt[kk+1]&LOWER_MASK);
rand->mt[kk] = rand->mt[kk+M] ^ (y >> 1) ^ mag01[y & 0x1]; rand->mt[kk] = rand->mt[kk+M] ^ (y >> 1) ^ mag01[y & 0x1];
} }
for (;kk<N-1;kk++) { for (; kk < N - 1; kk++) {
y = (rand->mt[kk]&UPPER_MASK)|(rand->mt[kk+1]&LOWER_MASK); y = (rand->mt[kk]&UPPER_MASK)|(rand->mt[kk+1]&LOWER_MASK);
rand->mt[kk] = rand->mt[kk+(M-N)] ^ (y >> 1) ^ mag01[y & 0x1]; rand->mt[kk] = rand->mt[kk+(M-N)] ^ (y >> 1) ^ mag01[y & 0x1];
} }
@@ -466,17 +474,19 @@ g_rand_int (GRand* rand)
/** /**
* g_rand_int_range: * g_rand_int_range:
* @rand_: a #GRand. * @rand_: a #GRand
* @begin: lower closed bound of the interval. * @begin: lower closed bound of the interval
* @end: upper open bound of the interval. * @end: upper open bound of the interval
* *
* Returns the next random #gint32 from @rand_ equally distributed over * Returns the next random #gint32 from @rand_ equally distributed over
* the range [@begin..@end-1]. * the range [@begin..@end-1].
* *
* Return value: A random number. * Return value: a random number
**/ */
gint32 gint32
g_rand_int_range (GRand* rand, gint32 begin, gint32 end) g_rand_int_range (GRand *rand,
gint32 begin,
gint32 end)
{ {
guint32 dist = end - begin; guint32 dist = end - begin;
guint32 random; guint32 random;
@@ -491,9 +501,9 @@ g_rand_int_range (GRand* rand, gint32 begin, gint32 end)
{ {
/* This method, which only calls g_rand_int once is only good /* This method, which only calls g_rand_int once is only good
* for (end - begin) <= 2^16, because we only have 32 bits set * for (end - begin) <= 2^16, because we only have 32 bits set
* from the one call to g_rand_int (). */ * from the one call to g_rand_int ().
*
/* we are using (trans + trans * trans), because g_rand_int only * We are using (trans + trans * trans), because g_rand_int only
* covers [0..2^32-1] and thus g_rand_int * trans only covers * covers [0..2^32-1] and thus g_rand_int * trans only covers
* [0..1-2^-32], but the biggest double < 1 is 1-2^-52. * [0..1-2^-32], but the biggest double < 1 is 1-2^-52.
*/ */
@@ -506,9 +516,10 @@ g_rand_int_range (GRand* rand, gint32 begin, gint32 end)
} }
else else
{ {
/* Now we use g_rand_double_range (), which will set 52 bits for /* Now we use g_rand_double_range (), which will set 52 bits
us, so that it is safe to round and still get a decent * for us, so that it is safe to round and still get a decent
distribution */ * distribution
*/
random = (gint32) g_rand_double_range (rand, 0, dist); random = (gint32) g_rand_double_range (rand, 0, dist);
} }
break; break;
@@ -518,7 +529,8 @@ g_rand_int_range (GRand* rand, gint32 begin, gint32 end)
else else
{ {
/* maxvalue is set to the predecessor of the greatest /* maxvalue is set to the predecessor of the greatest
* multiple of dist less or equal 2^32. */ * multiple of dist less or equal 2^32.
*/
guint32 maxvalue; guint32 maxvalue;
if (dist <= 0x80000000u) /* 2^31 */ if (dist <= 0x80000000u) /* 2^31 */
{ {
@@ -547,15 +559,15 @@ g_rand_int_range (GRand* rand, gint32 begin, gint32 end)
/** /**
* g_rand_double: * g_rand_double:
* @rand_: a #GRand. * @rand_: a #GRand
* *
* Returns the next random #gdouble from @rand_ equally distributed over * Returns the next random #gdouble from @rand_ equally distributed over
* the range [0..1). * the range [0..1).
* *
* Return value: A random number. * Return value: a random number
**/ */
gdouble gdouble
g_rand_double (GRand* rand) g_rand_double (GRand *rand)
{ {
/* We set all 52 bits after the point for this, not only the first /* We set all 52 bits after the point for this, not only the first
32. Thats why we need two calls to g_rand_int */ 32. Thats why we need two calls to g_rand_int */
@@ -572,17 +584,19 @@ g_rand_double (GRand* rand)
/** /**
* g_rand_double_range: * g_rand_double_range:
* @rand_: a #GRand. * @rand_: a #GRand
* @begin: lower closed bound of the interval. * @begin: lower closed bound of the interval
* @end: upper open bound of the interval. * @end: upper open bound of the interval
* *
* Returns the next random #gdouble from @rand_ equally distributed over * Returns the next random #gdouble from @rand_ equally distributed over
* the range [@begin..@end). * the range [@begin..@end).
* *
* Return value: A random number. * Return value: a random number
**/ */
gdouble gdouble
g_rand_double_range (GRand* rand, gdouble begin, gdouble end) g_rand_double_range (GRand *rand,
gdouble begin,
gdouble end)
{ {
gdouble r; gdouble r;
@@ -606,18 +620,19 @@ get_global_random (void)
/** /**
* g_random_boolean: * g_random_boolean:
* *
* Returns a random #gboolean. This corresponds to a unbiased coin toss. * Returns a random #gboolean.
* This corresponds to a unbiased coin toss.
* *
* Returns: a random #gboolean. * Returns: a random #gboolean
**/ */
/** /**
* g_random_int: * g_random_int:
* *
* Return a random #guint32 equally distributed over the range * Return a random #guint32 equally distributed over the range
* [0..2^32-1]. * [0..2^32-1].
* *
* Return value: A random number. * Return value: a random number
**/ */
guint32 guint32
g_random_int (void) g_random_int (void)
{ {
@@ -630,16 +645,17 @@ g_random_int (void)
/** /**
* g_random_int_range: * g_random_int_range:
* @begin: lower closed bound of the interval. * @begin: lower closed bound of the interval
* @end: upper open bound of the interval. * @end: upper open bound of the interval
* *
* Returns a random #gint32 equally distributed over the range * Returns a random #gint32 equally distributed over the range
* [@begin..@end-1]. * [@begin..@end-1].
* *
* Return value: A random number. * Return value: a random number
**/ */
gint32 gint32
g_random_int_range (gint32 begin, gint32 end) g_random_int_range (gint32 begin,
gint32 end)
{ {
gint32 result; gint32 result;
G_LOCK (global_random); G_LOCK (global_random);
@@ -653,8 +669,8 @@ g_random_int_range (gint32 begin, gint32 end)
* *
* Returns a random #gdouble equally distributed over the range [0..1). * Returns a random #gdouble equally distributed over the range [0..1).
* *
* Return value: A random number. * Return value: a random number
**/ */
gdouble gdouble
g_random_double (void) g_random_double (void)
{ {
@@ -667,15 +683,17 @@ g_random_double (void)
/** /**
* g_random_double_range: * g_random_double_range:
* @begin: lower closed bound of the interval. * @begin: lower closed bound of the interval
* @end: upper open bound of the interval. * @end: upper open bound of the interval
* *
* Returns a random #gdouble equally distributed over the range [@begin..@end). * Returns a random #gdouble equally distributed over the range
* [@begin..@end).
* *
* Return value: A random number. * Return value: a random number
**/ */
gdouble gdouble
g_random_double_range (gdouble begin, gdouble end) g_random_double_range (gdouble begin,
gdouble end)
{ {
double result; double result;
G_LOCK (global_random); G_LOCK (global_random);
@@ -686,11 +704,11 @@ g_random_double_range (gdouble begin, gdouble end)
/** /**
* g_random_set_seed: * g_random_set_seed:
* @seed: a value to reinitialize the global random number generator. * @seed: a value to reinitialize the global random number generator
* *
* Sets the seed for the global random number generator, which is used * Sets the seed for the global random number generator, which is used
* by the g_random_* functions, to @seed. * by the g_random_* functions, to @seed.
**/ */
void void
g_random_set_seed (guint32 seed) g_random_set_seed (guint32 seed)
{ {