Even better documentation of filters.

This commit is contained in:
Pavel Machek 2000-06-07 14:16:11 +00:00
parent 7aa99d22bc
commit 8dcf254499
3 changed files with 30 additions and 9 deletions

View file

@ -25,7 +25,7 @@
* *
* Filters use structure &f_val for its variables. Each &f_val * Filters use structure &f_val for its variables. Each &f_val
* contains type and value. Types are constants prefixed with %T_. Few * contains type and value. Types are constants prefixed with %T_. Few
* of types are special; %T_RETURN can be or-ed with type to indicate * of types are special; %T_RETURN can be or--ed with type to indicate
* that return from function/from whole filter should be * that return from function/from whole filter should be
* forced. Important thing about &f_val s is that they may be copied * forced. Important thing about &f_val s is that they may be copied
* with simple =. That's fine for all currently defined types: strings * with simple =. That's fine for all currently defined types: strings
@ -71,8 +71,14 @@ pm_path_compare(struct f_path_mask *m1, struct f_path_mask *m2)
} }
} }
/* /**
* val_compare - compare two values, returns -1, 0, 1 on <, =, > and 999 on error * val_compare
* @v1: first value
* @v2: second value
*
* Compares two values and returns -1, 0, 1 on <, =, > or 999 on error.
* Tree module relies on this giving consistent results so that it can
* build balanced trees.
*/ */
int int
val_compare(struct f_val v1, struct f_val v2) val_compare(struct f_val v1, struct f_val v2)
@ -140,8 +146,13 @@ val_simple_in_range(struct f_val v1, struct f_val v2)
return CMP_ERROR; return CMP_ERROR;
} }
/* /**
* val_in_range - check if @v1 ~ @v2 * val_in_range
* @v1: element
* @v2: set
*
* Checks if @v1 is element (|~| operator) of @v2. Sets are internally represented as balanced trees, see
* tree.c module (this is not limited to sets, but for non-set cases, val_simple_in_range() is called early).
*/ */
int int
val_in_range(struct f_val v1, struct f_val v2) val_in_range(struct f_val v1, struct f_val v2)

View file

@ -11,7 +11,7 @@
#include "filter/filter.h" #include "filter/filter.h"
/* /*
* find_nth - finds n-th element in linked list. Don't be confused by tree structures. * find_nth - finds n-th element in linked list. Don't be confused by types, it is really a linked list.
*/ */
static struct f_tree * static struct f_tree *
find_nth(struct f_tree *from, int nth) find_nth(struct f_tree *from, int nth)
@ -44,7 +44,7 @@ find_nth(struct f_tree *from, int nth)
} }
/* /*
* find_median - Gets list linked by left, finds its median, trashes pointers in right * find_median - Gets list linked by @left, finds its median, trashes pointers in @right.
*/ */
static struct f_tree * static struct f_tree *
find_median(struct f_tree *from) find_median(struct f_tree *from)
@ -69,6 +69,9 @@ find_median(struct f_tree *from)
* Search for given value in the tree. I relies on fact that sorted tree is populated * Search for given value in the tree. I relies on fact that sorted tree is populated
* by &f_val structures (that can be compared by val_compare()). In each node of tree, * by &f_val structures (that can be compared by val_compare()). In each node of tree,
* either single value (then t->from==t->to) or range is present. * either single value (then t->from==t->to) or range is present.
*
* Both set matching and switch() { } construction is implemented using this function,
* thus both are as fast as they can be.
*/ */
struct f_tree * struct f_tree *
find_tree(struct f_tree *t, struct f_val val) find_tree(struct f_tree *t, struct f_val val)
@ -86,7 +89,7 @@ find_tree(struct f_tree *t, struct f_val val)
/** /**
* build_tree * build_tree
* @from: degenerated tree (linked by tree->left) to be transformed into form suitable for find_tree() * @from: degenerated tree (linked by @tree->left) to be transformed into form suitable for find_tree()
* *
* Transforms denerated tree into balanced tree. * Transforms denerated tree into balanced tree.
*/ */
@ -130,6 +133,13 @@ f_new_tree(void)
return ret; return ret;
} }
/**
* same_tree
* @t1: first tree to be compared
* @t2: second one
*
* Compares two trees and returns 1 if they are same
*/
int int
same_tree(struct f_tree *t1, struct f_tree *t2) same_tree(struct f_tree *t1, struct f_tree *t2)
{ {