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haproxy/include/import/cebtree-prv.h

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/*
* Compact Elastic Binary Trees - internal functions and types
*
* Copyright (C) 2014-2024 Willy Tarreau - w@1wt.eu
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
/* This file MUST NOT be included by public code, it contains macros, enums
* with short names and function definitions that may clash with user code.
* It may only be included by the respective types' C files.
*/
/*
* These trees are optimized for adding the minimalest overhead to the stored
* data. This version uses the node's pointer as the key, for the purpose of
* quickly finding its neighbours.
*
* A few properties :
* - the xor between two branches of a node cannot be zero unless the two
* branches are duplicate keys
* - the xor between two nodes has *at least* the split bit set, possibly more
* - the split bit is always strictly smaller for a node than for its parent,
* which implies that the xor between the keys of the lowest level node is
* always smaller than the xor between a higher level node. Hence the xor
* between the branches of a regular leaf is always strictly larger than the
* xor of its parent node's branches if this node is different, since the
* leaf is associated with a higher level node which has at least one higher
* level branch. The first leaf doesn't validate this but is handled by the
* rules below.
* - during the descent, the node corresponding to a leaf is always visited
* before the leaf, unless it's the first inserted, nodeless leaf.
* - the first key is the only one without any node, and it has both its
* branches pointing to itself during insertion to detect it (i.e. xor==0).
* - a leaf is always present as a node on the path from the root, except for
* the inserted first key which has no node, and is recognizable by its two
* branches pointing to itself.
* - a consequence of the rules above is that a non-first leaf appearing below
* a node will necessarily have an associated node with a split bit equal to
* or greater than the node's split bit.
* - another consequence is that below a node, the split bits are different for
* each branches since both of them are already present above the node, thus
* at different levels, so their respective XOR values will be different.
* - since all nodes in a given path have a different split bit, if a leaf has
* the same split bit as its parent node, it is necessary its associated leaf
*
* When descending along the tree, it is possible to know that a search key is
* not present, because its XOR with both of the branches is stricly higher
* than the inter-branch XOR. The reason is simple : the inter-branch XOR will
* have its highest bit set indicating the split bit. Since it's the bit that
* differs between the two branches, the key cannot have it both set and
* cleared when comparing to the branch values. So xoring the key with both
* branches will emit a higher bit only when the key's bit differs from both
* branches' similar bit. Thus, the following equation :
* (XOR(key, L) > XOR(L, R)) && (XOR(key, R) > XOR(L, R))
* is only true when the key should be placed above that node. Since the key
* has a higher bit which differs from the node, either it has it set and the
* node has it clear (same for both branches), or it has it clear and the node
* has it set for both branches. For this reason it's enough to compare the key
* with any node when the equation above is true, to know if it ought to be
* present on the left or on the right side. This is useful for insertion and
* for range lookups.
*/
#ifndef _CEBTREE_PRV_H
#define _CEBTREE_PRV_H
#include <inttypes.h>
#include <string.h>
#include "cebtree.h"
/* If DEBUG is set, we'll print additional debugging info during the descent */
#ifdef DEBUG
#define CEBDBG(x, ...) fprintf(stderr, x, ##__VA_ARGS__)
#else
#define CEBDBG(x, ...) do { } while (0)
#endif
/* These macros are used by upper level files to create two variants of their
* exported functions:
* - one which uses sizeof(struct ceb_node) as the key offset, for nodes with
* adjacent keys ; these ones are named <pfx><sfx>(root, ...)
* - one with an explicit key offset passed by the caller right after the
* root.
* Both rely on a forced inline version with a body that immediately follows
* the declaration, so that the declaration looks like a single decorated
* function while 2 are built in practice. There are variants for the basic one
* with 0, 1 and 2 extra arguments after the root. The root and the key offset
* are always the first two arguments, and the key offset never appears in the
* first variant, it's always replaced by sizeof(struct ceb_node) in the calls
* to the inline version.
*/
#define CEB_FDECL2(type, pfx, sfx, type1, arg1, type2, arg2) \
static inline __attribute__((always_inline)) \
type _##pfx##sfx(type1 arg1, type2 arg2); \
type pfx##sfx(type1 arg1) { \
return _##pfx##sfx(arg1, sizeof(struct ceb_node)); \
} \
type pfx##_ofs##sfx(type1 arg1, type2 arg2) { \
return _##pfx##sfx(arg1, arg2); \
} \
static inline __attribute__((always_inline)) \
type _##pfx##sfx(type1 arg1, type2 arg2)
/* function body follows */
#define CEB_FDECL3(type, pfx, sfx, type1, arg1, type2, arg2, type3, arg3) \
static inline __attribute__((always_inline)) \
type _##pfx##sfx(type1 arg1, type2 arg2, type3 arg3); \
type pfx##sfx(type1 arg1, type3 arg3) { \
return _##pfx##sfx(arg1, sizeof(struct ceb_node), arg3); \
} \
type pfx##_ofs##sfx(type1 arg1, type2 arg2, type3 arg3) { \
return _##pfx##sfx(arg1, arg2, arg3); \
} \
static inline __attribute__((always_inline)) \
type _##pfx##sfx(type1 arg1, type2 arg2, type3 arg3)
/* function body follows */
#define CEB_FDECL4(type, pfx, sfx, type1, arg1, type2, arg2, type3, arg3, type4, arg4) \
static inline __attribute__((always_inline)) \
type _##pfx##sfx(type1 arg1, type2 arg2, type3 arg3, type4 arg4); \
type pfx##sfx(type1 arg1, type3 arg3, type4 arg4) { \
return _##pfx##sfx(arg1, sizeof(struct ceb_node), arg3, arg4); \
} \
type pfx##_ofs##sfx(type1 arg1, type2 arg2, type3 arg3, type4 arg4) { \
return _##pfx##sfx(arg1, arg2, arg3, arg4); \
} \
static inline __attribute__((always_inline)) \
type _##pfx##sfx(type1 arg1, type2 arg2, type3 arg3, type4 arg4)
/* function body follows */
/* tree walk method: key, left, right */
enum ceb_walk_meth {
CEB_WM_FST, /* look up "first" (walk left only) */
CEB_WM_NXT, /* look up "next" (walk right once then left) */
CEB_WM_PRV, /* look up "prev" (walk left once then right) */
CEB_WM_LST, /* look up "last" (walk right only) */
/* all methods from CEB_WM_KEQ and above do have a key */
CEB_WM_KEQ, /* look up the node equal to the key */
CEB_WM_KGE, /* look up the node greater than or equal to the key */
CEB_WM_KGT, /* look up the node greater than the key */
CEB_WM_KLE, /* look up the node lower than or equal to the key */
CEB_WM_KLT, /* look up the node lower than the key */
CEB_WM_KNX, /* look up the node's key first, then find the next */
CEB_WM_KPR, /* look up the node's key first, then find the prev */
};
enum ceb_key_type {
CEB_KT_ADDR, /* the key is the node's address */
CEB_KT_U32, /* 32-bit unsigned word in key_u32 */
CEB_KT_U64, /* 64-bit unsigned word in key_u64 */
CEB_KT_MB, /* fixed size memory block in (key_u64,key_ptr), direct storage */
CEB_KT_IM, /* fixed size memory block in (key_u64,key_ptr), indirect storage */
CEB_KT_ST, /* NUL-terminated string in key_ptr, direct storage */
CEB_KT_IS, /* NUL-terminated string in key_ptr, indirect storage */
};
union ceb_key_storage {
uint32_t u32;
uint64_t u64;
unsigned long ul;
unsigned char mb[0];
unsigned char str[0];
unsigned char *ptr; /* for CEB_KT_IS */
};
/* returns the ceb_key_storage pointer for node <n> and offset <o> */
#define NODEK(n, o) ((union ceb_key_storage*)(((char *)(n)) + (o)))
/* Returns the xor (or common length) between the two sides <l> and <r> if both
* are non-null, otherwise between the first non-null one and the value in the
* associate key. As a reminder, memory blocks place their length in key_u64.
* This is only intended for internal use, essentially for debugging.
*
* <kofs> contains the offset between the key and the node's base. When simply
* adjacent, this would just be sizeof(ceb_node).
*/
__attribute__((unused))
static inline uint64_t _xor_branches(ptrdiff_t kofs, enum ceb_key_type key_type, uint32_t key_u32,
uint64_t key_u64, const void *key_ptr,
const struct ceb_node *l,
const struct ceb_node *r)
{
if (l && r) {
if (key_type == CEB_KT_MB)
return equal_bits(NODEK(l, kofs)->mb, NODEK(r, kofs)->mb, 0, key_u64 << 3);
else if (key_type == CEB_KT_IM)
return equal_bits(NODEK(l, kofs)->mb, NODEK(r, kofs)->ptr, 0, key_u64 << 3);
else if (key_type == CEB_KT_ST)
return string_equal_bits(NODEK(l, kofs)->str, NODEK(r, kofs)->str, 0);
else if (key_type == CEB_KT_IS)
return string_equal_bits(NODEK(l, kofs)->ptr, NODEK(r, kofs)->ptr, 0);
else if (key_type == CEB_KT_U64)
return NODEK(l, kofs)->u64 ^ NODEK(r, kofs)->u64;
else if (key_type == CEB_KT_U32)
return NODEK(l, kofs)->u32 ^ NODEK(r, kofs)->u32;
else if (key_type == CEB_KT_ADDR)
return ((uintptr_t)l ^ (uintptr_t)r);
else
return 0;
}
if (!l)
l = r;
if (key_type == CEB_KT_MB)
return equal_bits(key_ptr, NODEK(l, kofs)->mb, 0, key_u64 << 3);
else if (key_type == CEB_KT_IM)
return equal_bits(key_ptr, NODEK(l, kofs)->ptr, 0, key_u64 << 3);
else if (key_type == CEB_KT_ST)
return string_equal_bits(key_ptr, NODEK(l, kofs)->str, 0);
else if (key_type == CEB_KT_IS)
return string_equal_bits(key_ptr, NODEK(l, kofs)->ptr, 0);
else if (key_type == CEB_KT_U64)
return key_u64 ^ NODEK(l, kofs)->u64;
else if (key_type == CEB_KT_U32)
return key_u32 ^ NODEK(l, kofs)->u32;
else if (key_type == CEB_KT_ADDR)
return ((uintptr_t)key_ptr ^ (uintptr_t)r);
else
return 0;
}
#ifdef DEBUG
__attribute__((unused))
static void dbg(int line,
const char *pfx,
enum ceb_walk_meth meth,
ptrdiff_t kofs,
enum ceb_key_type key_type,
struct ceb_node * const *root,
const struct ceb_node *p,
uint32_t key_u32,
uint64_t key_u64,
const void *key_ptr,
uint32_t px32,
uint64_t px64,
size_t plen)
{
const char *meths[] = {
[CEB_WM_FST] = "FST",
[CEB_WM_NXT] = "NXT",
[CEB_WM_PRV] = "PRV",
[CEB_WM_LST] = "LST",
[CEB_WM_KEQ] = "KEQ",
[CEB_WM_KGE] = "KGE",
[CEB_WM_KGT] = "KGT",
[CEB_WM_KLE] = "KLE",
[CEB_WM_KLT] = "KLT",
[CEB_WM_KNX] = "KNX",
[CEB_WM_KPR] = "KPR",
};
const char *ktypes[] = {
[CEB_KT_ADDR] = "ADDR",
[CEB_KT_U32] = "U32",
[CEB_KT_U64] = "U64",
[CEB_KT_MB] = "MB",
[CEB_KT_IM] = "IM",
[CEB_KT_ST] = "ST",
[CEB_KT_IS] = "IS",
};
const char *kstr __attribute__((unused)) = ktypes[key_type];
const char *mstr __attribute__((unused)) = meths[meth];
long long nlen __attribute__((unused)) = 0;
long long llen __attribute__((unused)) = 0;
long long rlen __attribute__((unused)) = 0;
long long xlen __attribute__((unused)) = 0;
if (p)
nlen = _xor_branches(kofs, key_type, key_u32, key_u64, key_ptr, p, NULL);
if (p && p->b[0])
llen = _xor_branches(kofs, key_type, key_u32, key_u64, key_ptr, p->b[0], NULL);
if (p && p->b[1])
rlen = _xor_branches(kofs, key_type, key_u32, key_u64, key_ptr, NULL, p->b[1]);
if (p && p->b[0] && p->b[1])
xlen = _xor_branches(kofs, key_type, key_u32, key_u64, key_ptr, p->b[0], p->b[1]);
switch (key_type) {
case CEB_KT_U32:
CEBDBG("%04d (%8s) m=%s.%s key=%#x root=%p pxor=%#x p=%p,%#x(^%#llx) l=%p,%#x(^%#llx) r=%p,%#x(^%#llx) l^r=%#llx\n",
line, pfx, kstr, mstr, key_u32, root, px32,
p, p ? NODEK(p, kofs)->u32 : 0, nlen,
p ? p->b[0] : NULL, p ? NODEK(p->b[0], kofs)->u32 : 0, llen,
p ? p->b[1] : NULL, p ? NODEK(p->b[1], kofs)->u32 : 0, rlen,
xlen);
break;
case CEB_KT_U64:
CEBDBG("%04d (%8s) m=%s.%s key=%#llx root=%p pxor=%#llx p=%p,%#llx(^%#llx) l=%p,%#llx(^%#llx) r=%p,%#llx(^%#llx) l^r=%#llx\n",
line, pfx, kstr, mstr, (long long)key_u64, root, (long long)px64,
p, (long long)(p ? NODEK(p, kofs)->u64 : 0), nlen,
p ? p->b[0] : NULL, (long long)(p ? NODEK(p->b[0], kofs)->u64 : 0), llen,
p ? p->b[1] : NULL, (long long)(p ? NODEK(p->b[1], kofs)->u64 : 0), rlen,
xlen);
break;
case CEB_KT_MB:
CEBDBG("%04d (%8s) m=%s.%s key=%p root=%p plen=%ld p=%p,%p(^%llu) l=%p,%p(^%llu) r=%p,%p(^%llu) l^r=%llu\n",
line, pfx, kstr, mstr, key_ptr, root, (long)plen,
p, p ? NODEK(p, kofs)->mb : 0, nlen,
p ? p->b[0] : NULL, p ? NODEK(p->b[0], kofs)->mb : 0, llen,
p ? p->b[1] : NULL, p ? NODEK(p->b[1], kofs)->mb : 0, rlen,
xlen);
break;
case CEB_KT_IM:
CEBDBG("%04d (%8s) m=%s.%s key=%p root=%p plen=%ld p=%p,%p(^%llu) l=%p,%p(^%llu) r=%p,%p(^%llu) l^r=%llu\n",
line, pfx, kstr, mstr, key_ptr, root, (long)plen,
p, p ? NODEK(p, kofs)->ptr : 0, nlen,
p ? p->b[0] : NULL, p ? NODEK(p->b[0], kofs)->ptr : 0, llen,
p ? p->b[1] : NULL, p ? NODEK(p->b[1], kofs)->ptr : 0, rlen,
xlen);
break;
case CEB_KT_ST:
CEBDBG("%04d (%8s) m=%s.%s key='%s' root=%p plen=%ld p=%p,%s(^%llu) l=%p,%s(^%llu) r=%p,%s(^%llu) l^r=%llu\n",
line, pfx, kstr, mstr, key_ptr ? (const char *)key_ptr : "", root, (long)plen,
p, p ? (const char *)NODEK(p, kofs)->str : "-", nlen,
p ? p->b[0] : NULL, p ? (const char *)NODEK(p->b[0], kofs)->str : "-", llen,
p ? p->b[1] : NULL, p ? (const char *)NODEK(p->b[1], kofs)->str : "-", rlen,
xlen);
break;
case CEB_KT_IS:
CEBDBG("%04d (%8s) m=%s.%s key='%s' root=%p plen=%ld p=%p,%s(^%llu) l=%p,%s(^%llu) r=%p,%s(^%llu) l^r=%llu\n",
line, pfx, kstr, mstr, key_ptr ? (const char *)key_ptr : "", root, (long)plen,
p, p ? (const char *)NODEK(p, kofs)->ptr : "-", nlen,
p ? p->b[0] : NULL, p ? (const char *)NODEK(p->b[0], kofs)->ptr : "-", llen,
p ? p->b[1] : NULL, p ? (const char *)NODEK(p->b[1], kofs)->ptr : "-", rlen,
xlen);
break;
case CEB_KT_ADDR:
/* key type is the node's address */
CEBDBG("%04d (%8s) m=%s.%s key=%#llx root=%p pxor=%#llx p=%p,%#llx(^%#llx) l=%p,%#llx(^%#llx) r=%p,%#llx(^%#llx) l^r=%#llx\n",
line, pfx, kstr, mstr, (long long)(uintptr_t)key_ptr, root, (long long)px64,
p, (long long)(uintptr_t)p, nlen,
p ? p->b[0] : NULL, p ? (long long)(uintptr_t)p->b[0] : 0, llen,
p ? p->b[1] : NULL, p ? (long long)(uintptr_t)p->b[1] : 0, rlen,
xlen);
}
}
#else
#define dbg(...) do { } while (0)
#endif
/* Generic tree descent function. It must absolutely be inlined so that the
* compiler can eliminate the tests related to the various return pointers,
* which must either point to a local variable in the caller, or be NULL.
* It must not be called with an empty tree, it's the caller business to
* deal with this special case. It returns in ret_root the location of the
* pointer to the leaf (i.e. where we have to insert ourselves). The integer
* pointed to by ret_nside will contain the side the leaf should occupy at
* its own node, with the sibling being *ret_root. Note that keys for fixed-
* size arrays are passed in key_ptr with their length in key_u64. For keyless
* nodes whose address serves as the key, the pointer needs to be passed in
* key_ptr, and pxor64 will be used internally.
*/
static inline __attribute__((always_inline))
struct ceb_node *_cebu_descend(struct ceb_node **root,
enum ceb_walk_meth meth,
ptrdiff_t kofs,
enum ceb_key_type key_type,
uint32_t key_u32,
uint64_t key_u64,
const void *key_ptr,
int *ret_nside,
struct ceb_node ***ret_root,
struct ceb_node **ret_lparent,
int *ret_lpside,
struct ceb_node **ret_nparent,
int *ret_npside,
struct ceb_node **ret_gparent,
int *ret_gpside,
struct ceb_node **ret_back)
{
#if !defined(__OPTIMIZE__) && __GNUC_PREREQ__(12, 0)
/* Avoid a bogus warning with gcc 12 and above: it warns about negative
* memcmp() length in non-existing code paths at -O0, as reported here:
* https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114622
*/
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wstringop-overread"
#endif
struct ceb_node *p;
union ceb_key_storage *l, *r, *k;
struct ceb_node *gparent = NULL;
struct ceb_node *nparent = NULL;
struct ceb_node *bnode = NULL;
struct ceb_node *lparent;
uint32_t pxor32 = ~0U; // previous xor between branches
uint64_t pxor64 = ~0ULL; // previous xor between branches
int gpside = 0; // side on the grand parent
int npside = 0; // side on the node's parent
long lpside = 0; // side on the leaf's parent
long brside = 0; // branch side when descending
size_t llen = 0; // left vs key matching length
size_t rlen = 0; // right vs key matching length
size_t plen = 0; // previous common len between branches
int found = 0; // key was found (saves an extra strcmp for arrays)
dbg(__LINE__, "_enter__", meth, kofs, key_type, root, NULL, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
/* the parent will be the (possibly virtual) node so that
* &lparent->l == root.
*/
lparent = container_of(root, struct ceb_node, b[0]);
gparent = nparent = lparent;
/* for key-less descents we need to set the initial branch to take */
switch (meth) {
case CEB_WM_NXT:
case CEB_WM_LST:
brside = 1; // start right for next/last
break;
case CEB_WM_FST:
case CEB_WM_PRV:
default:
brside = 0; // start left for first/prev
break;
}
/* the previous xor is initialized to the largest possible inter-branch
* value so that it can never match on the first test as we want to use
* it to detect a leaf vs node. That's achieved with plen==0 for arrays
* and pxorXX==~0 for scalars.
*/
while (1) {
p = *root;
/* Tests have shown that for write-intensive workloads (many
* insertions/deletion), prefetching for reads is counter
* productive (-10% perf) but that prefetching only the next
* nodes for writes when deleting can yield around 3% extra
* boost.
*/
if (ret_lpside) {
/* this is a deletion, prefetch for writes */
__builtin_prefetch(p->b[0], 1);
__builtin_prefetch(p->b[1], 1);
}
/* neither pointer is tagged */
k = NODEK(p, kofs);
l = NODEK(p->b[0], kofs);
r = NODEK(p->b[1], kofs);
dbg(__LINE__, "newp", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
/* two equal pointers identifies the nodeless leaf. */
if (l == r) {
dbg(__LINE__, "l==r", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
/* In the following block, we're dealing with type-specific
* operations which follow the same construct for each type:
* 1) calculate the new side for key lookups (otherwise keep
* the current side, e.g. for first/last). Doing it early
* allows the CPU to more easily predict next branches and
* is faster by ~10%. For complex bits we keep the length
* of identical bits instead of xor. We can also xor lkey
* and rkey with key and use it everywhere later but it
* doesn't seem to bring anything.
*
* 2) calculate the xor between the two sides to figure the
* split bit position. If the new split bit is before the
* previous one, we've reached a leaf: each leaf we visit
* had its node part already visited. The only way to
* distinguish them is that the inter-branch xor of the
* leaf will be the node's one, and will necessarily be
* larger than the previous node's xor if the node is
* above (we've already checked for direct descendent
* below). Said differently, if an inter-branch xor is
* strictly larger than the previous one, it necessarily
* is the one of an upper node, so what we're seeing
* cannot be the node, hence it's the leaf. The case where
* they're equal was already dealt with by the test at the
* end of the loop (node points to self). For scalar keys,
* we directly store the last xor value in pxorXX. For
* arrays and strings, instead we store the previous equal
* length.
*
* 3) for lookups, check if the looked key still has a chance
* to be below: if it has a xor with both branches that is
* larger than the xor between them, it cannot be there,
* since it means that it differs from these branches by
* at least one bit that's higher than the split bit,
* hence not common to these branches. In such cases:
* - if we're just doing a lookup, the key is not found
* and we fail.
* - if we are inserting, we must stop here and we have
* the guarantee to be above a node.
* - if we're deleting, it could be the key we were
* looking for so we have to check for it as long as
* it's still possible to keep a copy of the node's
* parent. <found> is set int this case for expensive
* types.
*/
if (key_type == CEB_KT_U32) {
uint32_t xor32; // left vs right branch xor
uint32_t kl, kr;
kl = l->u32; kr = r->u32;
xor32 = kl ^ kr;
if (xor32 > pxor32) { // test using 2 4 6 4
dbg(__LINE__, "xor>", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
if (meth >= CEB_WM_KEQ) {
/* "found" is not used here */
kl ^= key_u32; kr ^= key_u32;
brside = kl >= kr;
/* let's stop if our key is not there */
if (kl > xor32 && kr > xor32) {
dbg(__LINE__, "mismatch", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
if (ret_npside || ret_nparent) {
if (key_u32 == k->u32) {
dbg(__LINE__, "equal", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
nparent = lparent;
npside = lpside;
}
}
}
pxor32 = xor32;
}
else if (key_type == CEB_KT_U64) {
uint64_t xor64; // left vs right branch xor
uint64_t kl, kr;
kl = l->u64; kr = r->u64;
xor64 = kl ^ kr;
if (xor64 > pxor64) { // test using 2 4 6 4
dbg(__LINE__, "xor>", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
if (meth >= CEB_WM_KEQ) {
/* "found" is not used here */
kl ^= key_u64; kr ^= key_u64;
brside = kl >= kr;
/* let's stop if our key is not there */
if (kl > xor64 && kr > xor64) {
dbg(__LINE__, "mismatch", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
if (ret_npside || ret_nparent) {
if (key_u64 == k->u64) {
dbg(__LINE__, "equal", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
nparent = lparent;
npside = lpside;
}
}
}
pxor64 = xor64;
}
else if (key_type == CEB_KT_MB) {
size_t xlen = 0; // left vs right matching length
if (meth >= CEB_WM_KEQ) {
/* measure identical lengths */
llen = equal_bits(key_ptr, l->mb, 0, key_u64 << 3);
rlen = equal_bits(key_ptr, r->mb, 0, key_u64 << 3);
brside = llen <= rlen;
if (llen == rlen && (uint64_t)llen == key_u64 << 3)
found = 1;
}
xlen = equal_bits(l->mb, r->mb, 0, key_u64 << 3);
if (xlen < plen) {
/* this is a leaf. E.g. triggered using 2 4 6 4 */
dbg(__LINE__, "xor>", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
if (meth >= CEB_WM_KEQ) {
/* let's stop if our key is not there */
if (llen < xlen && rlen < xlen) {
dbg(__LINE__, "mismatch", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
if (ret_npside || ret_nparent) { // delete ?
size_t mlen = llen > rlen ? llen : rlen;
if (mlen > xlen)
mlen = xlen;
if ((uint64_t)xlen / 8 == key_u64 || memcmp(key_ptr + mlen / 8, k->mb + mlen / 8, key_u64 - mlen / 8) == 0) {
dbg(__LINE__, "equal", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
nparent = lparent;
npside = lpside;
found = 1;
}
}
}
plen = xlen;
}
else if (key_type == CEB_KT_IM) {
size_t xlen = 0; // left vs right matching length
if (meth >= CEB_WM_KEQ) {
/* measure identical lengths */
llen = equal_bits(key_ptr, l->ptr, 0, key_u64 << 3);
rlen = equal_bits(key_ptr, r->ptr, 0, key_u64 << 3);
brside = llen <= rlen;
if (llen == rlen && (uint64_t)llen == key_u64 << 3)
found = 1;
}
xlen = equal_bits(l->ptr, r->ptr, 0, key_u64 << 3);
if (xlen < plen) {
/* this is a leaf. E.g. triggered using 2 4 6 4 */
dbg(__LINE__, "xor>", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
if (meth >= CEB_WM_KEQ) {
/* let's stop if our key is not there */
if (llen < xlen && rlen < xlen) {
dbg(__LINE__, "mismatch", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
if (ret_npside || ret_nparent) { // delete ?
size_t mlen = llen > rlen ? llen : rlen;
if (mlen > xlen)
mlen = xlen;
if ((uint64_t)xlen / 8 == key_u64 || memcmp(key_ptr + mlen / 8, k->ptr + mlen / 8, key_u64 - mlen / 8) == 0) {
dbg(__LINE__, "equal", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
nparent = lparent;
npside = lpside;
found = 1;
}
}
}
plen = xlen;
}
else if (key_type == CEB_KT_ST) {
size_t xlen = 0; // left vs right matching length
if (meth >= CEB_WM_KEQ) {
/* Note that a negative length indicates an
* equal value with the final zero reached, but
* it is still needed to descend to find the
* leaf. We take that negative length for an
* infinite one, hence the uint cast.
*/
llen = string_equal_bits(key_ptr, l->str, 0);
rlen = string_equal_bits(key_ptr, r->str, 0);
brside = (size_t)llen <= (size_t)rlen;
if ((ssize_t)llen < 0 || (ssize_t)rlen < 0)
found = 1;
}
xlen = string_equal_bits(l->str, r->str, 0);
if (xlen < plen) {
/* this is a leaf. E.g. triggered using 2 4 6 4 */
dbg(__LINE__, "xor>", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
if (meth >= CEB_WM_KEQ) {
/* let's stop if our key is not there */
if ((unsigned)llen < (unsigned)xlen && (unsigned)rlen < (unsigned)xlen) {
dbg(__LINE__, "mismatch", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
if (ret_npside || ret_nparent) { // delete ?
size_t mlen = llen > rlen ? llen : rlen;
if (mlen > xlen)
mlen = xlen;
if (strcmp(key_ptr + mlen / 8, (const void *)k->str + mlen / 8) == 0) {
/* strcmp() still needed. E.g. 1 2 3 4 10 11 4 3 2 1 10 11 fails otherwise */
dbg(__LINE__, "equal", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
nparent = lparent;
npside = lpside;
found = 1;
}
}
}
plen = xlen;
}
else if (key_type == CEB_KT_IS) {
size_t xlen = 0; // left vs right matching length
if (meth >= CEB_WM_KEQ) {
/* Note that a negative length indicates an
* equal value with the final zero reached, but
* it is still needed to descend to find the
* leaf. We take that negative length for an
* infinite one, hence the uint cast.
*/
llen = string_equal_bits(key_ptr, l->ptr, 0);
rlen = string_equal_bits(key_ptr, r->ptr, 0);
brside = (size_t)llen <= (size_t)rlen;
if ((ssize_t)llen < 0 || (ssize_t)rlen < 0)
found = 1;
}
xlen = string_equal_bits(l->ptr, r->ptr, 0);
if (xlen < plen) {
/* this is a leaf. E.g. triggered using 2 4 6 4 */
dbg(__LINE__, "xor>", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
if (meth >= CEB_WM_KEQ) {
/* let's stop if our key is not there */
if ((unsigned)llen < (unsigned)xlen && (unsigned)rlen < (unsigned)xlen) {
dbg(__LINE__, "mismatch", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
if (ret_npside || ret_nparent) { // delete ?
size_t mlen = llen > rlen ? llen : rlen;
if (mlen > xlen)
mlen = xlen;
if (strcmp(key_ptr + mlen / 8, (const void *)k->ptr + mlen / 8) == 0) {
/* strcmp() still needed. E.g. 1 2 3 4 10 11 4 3 2 1 10 11 fails otherwise */
dbg(__LINE__, "equal", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
nparent = lparent;
npside = lpside;
found = 1;
}
}
}
plen = xlen;
}
else if (key_type == CEB_KT_ADDR) {
uintptr_t xoraddr; // left vs right branch xor
uintptr_t kl, kr;
kl = (uintptr_t)l; kr = (uintptr_t)r;
xoraddr = kl ^ kr;
if (xoraddr > (uintptr_t)pxor64) { // test using 2 4 6 4
dbg(__LINE__, "xor>", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
if (meth >= CEB_WM_KEQ) {
/* "found" is not used here */
kl ^= (uintptr_t)key_ptr; kr ^= (uintptr_t)key_ptr;
brside = kl >= kr;
/* let's stop if our key is not there */
if (kl > xoraddr && kr > xoraddr) {
dbg(__LINE__, "mismatch", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
if (ret_npside || ret_nparent) {
if ((uintptr_t)key_ptr == (uintptr_t)p) {
dbg(__LINE__, "equal", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
nparent = lparent;
npside = lpside;
}
}
}
pxor64 = xoraddr;
}
/* shift all copies by one */
gparent = lparent;
gpside = lpside;
lparent = p;
lpside = brside;
if (brside) {
if (meth == CEB_WM_KPR || meth == CEB_WM_KLE || meth == CEB_WM_KLT)
bnode = p;
root = &p->b[1];
/* change branch for key-less walks */
if (meth == CEB_WM_NXT)
brside = 0;
dbg(__LINE__, "side1", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
}
else {
if (meth == CEB_WM_KNX || meth == CEB_WM_KGE || meth == CEB_WM_KGT)
bnode = p;
root = &p->b[0];
/* change branch for key-less walks */
if (meth == CEB_WM_PRV)
brside = 1;
dbg(__LINE__, "side0", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
}
if (p == *root) {
/* loops over itself, it's a leaf */
dbg(__LINE__, "loop", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
break;
}
}
/* here we're on the closest node from the requested value. It may be
* slightly lower (has a zero where we expected a one) or slightly
* larger has a one where we expected a zero). Thus another check is
* still deserved, depending on the matching method.
*/
/* if we've exited on an exact match after visiting a regular node
* (i.e. not the nodeless leaf), we'll avoid checking the string again.
* However if it doesn't match, we must make sure to compare from
* within the key (which can be shorter than the ones already there),
* so we restart the check from the longest of the two lengths, which
* guarantees these bits exist. Test with "100", "10", "1" to see where
* this is needed.
*/
if ((key_type == CEB_KT_ST || key_type == CEB_KT_IS) && meth >= CEB_WM_KEQ && !found)
plen = (llen > rlen) ? llen : rlen;
/* update the pointers needed for modifications (insert, delete) */
if (ret_nside && meth >= CEB_WM_KEQ) {
switch (key_type) {
case CEB_KT_U32:
*ret_nside = key_u32 >= k->u32;
break;
case CEB_KT_U64:
*ret_nside = key_u64 >= k->u64;
break;
case CEB_KT_MB:
*ret_nside = (uint64_t)plen / 8 == key_u64 || memcmp(key_ptr + plen / 8, k->mb + plen / 8, key_u64 - plen / 8) >= 0;
break;
case CEB_KT_IM:
*ret_nside = (uint64_t)plen / 8 == key_u64 || memcmp(key_ptr + plen / 8, k->ptr + plen / 8, key_u64 - plen / 8) >= 0;
break;
case CEB_KT_ST:
*ret_nside = found || strcmp(key_ptr + plen / 8, (const void *)k->str + plen / 8) >= 0;
break;
case CEB_KT_IS:
*ret_nside = found || strcmp(key_ptr + plen / 8, (const void *)k->ptr + plen / 8) >= 0;
break;
case CEB_KT_ADDR:
*ret_nside = (uintptr_t)key_ptr >= (uintptr_t)p;
break;
}
}
if (ret_root)
*ret_root = root;
/* info needed by delete */
if (ret_lpside)
*ret_lpside = lpside;
if (ret_lparent)
*ret_lparent = lparent;
if (ret_npside)
*ret_npside = npside;
if (ret_nparent)
*ret_nparent = nparent;
if (ret_gpside)
*ret_gpside = gpside;
if (ret_gparent)
*ret_gparent = gparent;
if (ret_back)
*ret_back = bnode;
dbg(__LINE__, "_ret____", meth, kofs, key_type, root, p, key_u32, key_u64, key_ptr, pxor32, pxor64, plen);
if (meth >= CEB_WM_KEQ) {
/* For lookups, an equal value means an instant return. For insertions,
* it is the same, we want to return the previously existing value so
* that the caller can decide what to do. For deletion, we also want to
* return the pointer that's about to be deleted.
*/
if (key_type == CEB_KT_U32) {
if ((meth == CEB_WM_KEQ && k->u32 == key_u32) ||
(meth == CEB_WM_KNX && k->u32 == key_u32) ||
(meth == CEB_WM_KPR && k->u32 == key_u32) ||
(meth == CEB_WM_KGE && k->u32 >= key_u32) ||
(meth == CEB_WM_KGT && k->u32 > key_u32) ||
(meth == CEB_WM_KLE && k->u32 <= key_u32) ||
(meth == CEB_WM_KLT && k->u32 < key_u32))
return p;
}
else if (key_type == CEB_KT_U64) {
if ((meth == CEB_WM_KEQ && k->u64 == key_u64) ||
(meth == CEB_WM_KNX && k->u64 == key_u64) ||
(meth == CEB_WM_KPR && k->u64 == key_u64) ||
(meth == CEB_WM_KGE && k->u64 >= key_u64) ||
(meth == CEB_WM_KGT && k->u64 > key_u64) ||
(meth == CEB_WM_KLE && k->u64 <= key_u64) ||
(meth == CEB_WM_KLT && k->u64 < key_u64))
return p;
}
else if (key_type == CEB_KT_MB) {
int diff;
if ((uint64_t)plen / 8 == key_u64)
diff = 0;
else
diff = memcmp(k->mb + plen / 8, key_ptr + plen / 8, key_u64 - plen / 8);
if ((meth == CEB_WM_KEQ && diff == 0) ||
(meth == CEB_WM_KNX && diff == 0) ||
(meth == CEB_WM_KPR && diff == 0) ||
(meth == CEB_WM_KGE && diff >= 0) ||
(meth == CEB_WM_KGT && diff > 0) ||
(meth == CEB_WM_KLE && diff <= 0) ||
(meth == CEB_WM_KLT && diff < 0))
return p;
}
else if (key_type == CEB_KT_IM) {
int diff;
if ((uint64_t)plen / 8 == key_u64)
diff = 0;
else
diff = memcmp(k->ptr + plen / 8, key_ptr + plen / 8, key_u64 - plen / 8);
if ((meth == CEB_WM_KEQ && diff == 0) ||
(meth == CEB_WM_KNX && diff == 0) ||
(meth == CEB_WM_KPR && diff == 0) ||
(meth == CEB_WM_KGE && diff >= 0) ||
(meth == CEB_WM_KGT && diff > 0) ||
(meth == CEB_WM_KLE && diff <= 0) ||
(meth == CEB_WM_KLT && diff < 0))
return p;
}
else if (key_type == CEB_KT_ST) {
int diff;
if (found)
diff = 0;
else
diff = strcmp((const void *)k->str + plen / 8, key_ptr + plen / 8);
if ((meth == CEB_WM_KEQ && diff == 0) ||
(meth == CEB_WM_KNX && diff == 0) ||
(meth == CEB_WM_KPR && diff == 0) ||
(meth == CEB_WM_KGE && diff >= 0) ||
(meth == CEB_WM_KGT && diff > 0) ||
(meth == CEB_WM_KLE && diff <= 0) ||
(meth == CEB_WM_KLT && diff < 0))
return p;
}
else if (key_type == CEB_KT_IS) {
int diff;
if (found)
diff = 0;
else
diff = strcmp((const void *)k->ptr + plen / 8, key_ptr + plen / 8);
if ((meth == CEB_WM_KEQ && diff == 0) ||
(meth == CEB_WM_KNX && diff == 0) ||
(meth == CEB_WM_KPR && diff == 0) ||
(meth == CEB_WM_KGE && diff >= 0) ||
(meth == CEB_WM_KGT && diff > 0) ||
(meth == CEB_WM_KLE && diff <= 0) ||
(meth == CEB_WM_KLT && diff < 0))
return p;
}
else if (key_type == CEB_KT_ADDR) {
if ((meth == CEB_WM_KEQ && (uintptr_t)p == (uintptr_t)key_ptr) ||
(meth == CEB_WM_KNX && (uintptr_t)p == (uintptr_t)key_ptr) ||
(meth == CEB_WM_KPR && (uintptr_t)p == (uintptr_t)key_ptr) ||
(meth == CEB_WM_KGE && (uintptr_t)p >= (uintptr_t)key_ptr) ||
(meth == CEB_WM_KGT && (uintptr_t)p > (uintptr_t)key_ptr) ||
(meth == CEB_WM_KLE && (uintptr_t)p <= (uintptr_t)key_ptr) ||
(meth == CEB_WM_KLT && (uintptr_t)p < (uintptr_t)key_ptr))
return p;
}
} else if (meth == CEB_WM_FST || meth == CEB_WM_LST) {
return p;
} else if (meth == CEB_WM_PRV || meth == CEB_WM_NXT) {
return p;
}
/* lookups and deletes fail here */
/* let's return NULL to indicate the key was not found. For a lookup or
* a delete, it's a failure. For an insert, it's an invitation to the
* caller to proceed since the element is not there.
*/
return NULL;
#if __GNUC_PREREQ__(12, 0)
#pragma GCC diagnostic pop
#endif
}
/* Generic tree insertion function for trees with unique keys. Inserts node
* <node> into tree <tree>, with key type <key_type> and key <key_*>.
* Returns the inserted node or the one that already contains the same key.
*/
static inline __attribute__((always_inline))
struct ceb_node *_cebu_insert(struct ceb_node **root,
struct ceb_node *node,
ptrdiff_t kofs,
enum ceb_key_type key_type,
uint32_t key_u32,
uint64_t key_u64,
const void *key_ptr)
{
struct ceb_node **parent;
struct ceb_node *ret;
int nside;
if (!*root) {
/* empty tree, insert a leaf only */
node->b[0] = node->b[1] = node;
*root = node;
return node;
}
ret = _cebu_descend(root, CEB_WM_KEQ, kofs, key_type, key_u32, key_u64, key_ptr, &nside, &parent, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
if (!ret) {
/* The key was not in the tree, we can insert it. Better use an
* "if" like this because the inline function above already has
* quite identifiable code paths. This reduces the code and
* optimizes it a bit.
*/
if (nside) {
node->b[1] = node;
node->b[0] = *parent;
} else {
node->b[0] = node;
node->b[1] = *parent;
}
*parent = node;
ret = node;
}
return ret;
}
/* Returns the first node or NULL if not found, assuming a tree made of keys of
* type <key_type>.
*/
static inline __attribute__((always_inline))
struct ceb_node *_cebu_first(struct ceb_node **root,
ptrdiff_t kofs,
enum ceb_key_type key_type)
{
if (!*root)
return NULL;
return _cebu_descend(root, CEB_WM_FST, kofs, key_type, 0, 0, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
}
/* Returns the last node or NULL if not found, assuming a tree made of keys of
* type <key_type>.
*/
static inline __attribute__((always_inline))
struct ceb_node *_cebu_last(struct ceb_node **root,
ptrdiff_t kofs,
enum ceb_key_type key_type)
{
if (!*root)
return NULL;
return _cebu_descend(root, CEB_WM_LST, kofs, key_type, 0, 0, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
}
/* Searches in the tree <root> made of keys of type <key_type>, for the next
* node after the one containing the key <key_*>. Returns NULL if not found.
* It's up to the caller to pass the current node's key in <key_*>. The
* approach consists in looking up that node first, recalling the last time a
* left turn was made, and returning the first node along the right branch at
* that fork.
*/
static inline __attribute__((always_inline))
struct ceb_node *_cebu_next(struct ceb_node **root,
ptrdiff_t kofs,
enum ceb_key_type key_type,
uint32_t key_u32,
uint64_t key_u64,
const void *key_ptr)
{
struct ceb_node *restart;
if (!*root)
return NULL;
if (!_cebu_descend(root, CEB_WM_KNX, kofs, key_type, key_u32, key_u64, key_ptr, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, &restart))
return NULL;
if (!restart)
return NULL;
return _cebu_descend(&restart, CEB_WM_NXT, kofs, key_type, 0, 0, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
}
/* Searches in the tree <root> made of keys of type <key_type>, for the prev
* node before the one containing the key <key_*>. Returns NULL if not found.
* It's up to the caller to pass the current node's key in <key_*>. The
* approach consists in looking up that node first, recalling the last time a
* right turn was made, and returning the last node along the left branch at
* that fork.
*/
static inline __attribute__((always_inline))
struct ceb_node *_cebu_prev(struct ceb_node **root,
ptrdiff_t kofs,
enum ceb_key_type key_type,
uint32_t key_u32,
uint64_t key_u64,
const void *key_ptr)
{
struct ceb_node *restart;
if (!*root)
return NULL;
if (!_cebu_descend(root, CEB_WM_KPR, kofs, key_type, key_u32, key_u64, key_ptr, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, &restart))
return NULL;
if (!restart)
return NULL;
return _cebu_descend(&restart, CEB_WM_PRV, kofs, key_type, 0, 0, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
}
/* Searches in the tree <root> made of keys of type <key_type>, for the node
* containing the key <key_*>. Returns NULL if not found.
*/
static inline __attribute__((always_inline))
struct ceb_node *_cebu_lookup(struct ceb_node **root,
ptrdiff_t kofs,
enum ceb_key_type key_type,
uint32_t key_u32,
uint64_t key_u64,
const void *key_ptr)
{
if (!*root)
return NULL;
return _cebu_descend(root, CEB_WM_KEQ, kofs, key_type, key_u32, key_u64, key_ptr, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
}
/* Searches in the tree <root> made of keys of type <key_type>, for the node
* containing the key <key_*> or the highest one that's lower than it. Returns
* NULL if not found.
*/
static inline __attribute__((always_inline))
struct ceb_node *_cebu_lookup_le(struct ceb_node **root,
ptrdiff_t kofs,
enum ceb_key_type key_type,
uint32_t key_u32,
uint64_t key_u64,
const void *key_ptr)
{
struct ceb_node *ret = NULL;
struct ceb_node *restart;
if (!*root)
return NULL;
ret = _cebu_descend(root, CEB_WM_KLE, kofs, key_type, key_u32, key_u64, key_ptr, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, &restart);
if (ret)
return ret;
if (!restart)
return NULL;
return _cebu_descend(&restart, CEB_WM_PRV, kofs, key_type, 0, 0, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
}
/* Searches in the tree <root> made of keys of type <key_type>, for the node
* containing the greatest key that is strictly lower than <key_*>. Returns
* NULL if not found. It's very similar to next() except that the looked up
* value doesn't need to exist.
*/
static inline __attribute__((always_inline))
struct ceb_node *_cebu_lookup_lt(struct ceb_node **root,
ptrdiff_t kofs,
enum ceb_key_type key_type,
uint32_t key_u32,
uint64_t key_u64,
const void *key_ptr)
{
struct ceb_node *ret = NULL;
struct ceb_node *restart;
if (!*root)
return NULL;
ret = _cebu_descend(root, CEB_WM_KLT, kofs, key_type, key_u32, key_u64, key_ptr, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, &restart);
if (ret)
return ret;
if (!restart)
return NULL;
return _cebu_descend(&restart, CEB_WM_PRV, kofs, key_type, 0, 0, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
}
/* Searches in the tree <root> made of keys of type <key_type>, for the node
* containing the key <key_*> or the smallest one that's greater than it.
* Returns NULL if not found.
*/
static inline __attribute__((always_inline))
struct ceb_node *_cebu_lookup_ge(struct ceb_node **root,
ptrdiff_t kofs,
enum ceb_key_type key_type,
uint32_t key_u32,
uint64_t key_u64,
const void *key_ptr)
{
struct ceb_node *ret = NULL;
struct ceb_node *restart;
if (!*root)
return NULL;
ret = _cebu_descend(root, CEB_WM_KGE, kofs, key_type, key_u32, key_u64, key_ptr, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, &restart);
if (ret)
return ret;
if (!restart)
return NULL;
return _cebu_descend(&restart, CEB_WM_NXT, kofs, key_type, 0, 0, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
}
/* Searches in the tree <root> made of keys of type <key_type>, for the node
* containing the lowest key that is strictly greater than <key_*>. Returns
* NULL if not found. It's very similar to prev() except that the looked up
* value doesn't need to exist.
*/
static inline __attribute__((always_inline))
struct ceb_node *_cebu_lookup_gt(struct ceb_node **root,
ptrdiff_t kofs,
enum ceb_key_type key_type,
uint32_t key_u32,
uint64_t key_u64,
const void *key_ptr)
{
struct ceb_node *ret = NULL;
struct ceb_node *restart;
if (!*root)
return NULL;
ret = _cebu_descend(root, CEB_WM_KGT, kofs, key_type, key_u32, key_u64, key_ptr, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, &restart);
if (ret)
return ret;
if (!restart)
return NULL;
return _cebu_descend(&restart, CEB_WM_NXT, kofs, key_type, 0, 0, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
}
/* Searches in the tree <root> made of keys of type <key_type>, for the node
* that contains the key <key_*>, and deletes it. If <node> is non-NULL, a
* check is performed and the node found is deleted only if it matches. The
* found node is returned in any case, otherwise NULL if not found. A deleted
* node is detected since it has b[0]==NULL, which this functions also clears
* after operation. The function is idempotent, so it's safe to attempt to
* delete an already deleted node (NULL is returned in this case since the node
* was not in the tree).
*/
static inline __attribute__((always_inline))
struct ceb_node *_cebu_delete(struct ceb_node **root,
struct ceb_node *node,
ptrdiff_t kofs,
enum ceb_key_type key_type,
uint32_t key_u32,
uint64_t key_u64,
const void *key_ptr)
{
struct ceb_node *lparent, *nparent, *gparent;
int lpside, npside, gpside;
struct ceb_node *ret = NULL;
if (node && !node->b[0]) {
/* NULL on a branch means the node is not in the tree */
return NULL;
}
if (!*root) {
/* empty tree, the node cannot be there */
goto done;
}
ret = _cebu_descend(root, CEB_WM_KEQ, kofs, key_type, key_u32, key_u64, key_ptr, NULL, NULL,
&lparent, &lpside, &nparent, &npside, &gparent, &gpside, NULL);
if (!ret) {
/* key not found */
goto done;
}
if (ret == node || !node) {
if (&lparent->b[0] == root) {
/* there was a single entry, this one, so we're just
* deleting the nodeless leaf.
*/
*root = NULL;
goto mark_and_leave;
}
/* then we necessarily have a gparent */
gparent->b[gpside] = lparent->b[!lpside];
if (lparent == ret) {
/* we're removing the leaf and node together, nothing
* more to do.
*/
goto mark_and_leave;
}
if (ret->b[0] == ret->b[1]) {
/* we're removing the node-less item, the parent will
* take this role.
*/
lparent->b[0] = lparent->b[1] = lparent;
goto mark_and_leave;
}
/* more complicated, the node was split from the leaf, we have
* to find a spare one to switch it. The parent node is not
* needed anymore so we can reuse it.
*/
lparent->b[0] = ret->b[0];
lparent->b[1] = ret->b[1];
nparent->b[npside] = lparent;
mark_and_leave:
/* now mark the node as deleted */
ret->b[0] = NULL;
}
done:
return ret;
}
/*
* Functions used to dump trees in Dot format.
*/
/* dump the root and its link to the first node or leaf */
__attribute__((unused))
static void cebu_default_dump_root(ptrdiff_t kofs, enum ceb_key_type key_type, struct ceb_node *const *root, const void *ctx)
{
const struct ceb_node *node;
printf(" \"%lx_n\" [label=\"root\\n%lx\"]\n", (long)root, (long)root);
node = *root;
if (node) {
/* under the root we've either a node or the first leaf */
printf(" \"%lx_n\" -> \"%lx_%c\" [label=\"B\" arrowsize=0.66];\n",
(long)root, (long)node,
(node->b[0] == node->b[1]) ? 'l' : 'n');
}
}
/* dump a node */
__attribute__((unused))
static void cebu_default_dump_node(ptrdiff_t kofs, enum ceb_key_type key_type, const struct ceb_node *node, int level, const void *ctx)
{
unsigned long long int_key = 0;
uint64_t pxor, lxor, rxor;
switch (key_type) {
case CEB_KT_ADDR:
int_key = (uintptr_t)node;
break;
case CEB_KT_U32:
int_key = NODEK(node, kofs)->u32;
break;
case CEB_KT_U64:
int_key = NODEK(node, kofs)->u64;
break;
default:
break;
}
/* xor of the keys of the two lower branches */
pxor = _xor_branches(kofs, key_type, 0, 0, NULL,
node->b[0], node->b[1]);
/* xor of the keys of the left branch's lower branches */
lxor = _xor_branches(kofs, key_type, 0, 0, NULL,
(((struct ceb_node*)node->b[0])->b[0]),
(((struct ceb_node*)node->b[0])->b[1]));
/* xor of the keys of the right branch's lower branches */
rxor = _xor_branches(kofs, key_type, 0, 0, NULL,
(((struct ceb_node*)node->b[1])->b[0]),
(((struct ceb_node*)node->b[1])->b[1]));
switch (key_type) {
case CEB_KT_ADDR:
case CEB_KT_U32:
case CEB_KT_U64:
printf(" \"%lx_n\" [label=\"%lx\\nlev=%d bit=%d\\nkey=%llu\" fillcolor=\"lightskyblue1\"%s];\n",
(long)node, (long)node, level, flsnz(pxor) - 1, int_key, (ctx == node) ? " color=red" : "");
printf(" \"%lx_n\" -> \"%lx_%c\" [label=\"L\" arrowsize=0.66 %s];\n",
(long)node, (long)node->b[0],
(lxor < pxor && ((struct ceb_node*)node->b[0])->b[0] != ((struct ceb_node*)node->b[0])->b[1]) ? 'n' : 'l',
(node == node->b[0]) ? " dir=both" : "");
printf(" \"%lx_n\" -> \"%lx_%c\" [label=\"R\" arrowsize=0.66 %s];\n",
(long)node, (long)node->b[1],
(rxor < pxor && ((struct ceb_node*)node->b[1])->b[0] != ((struct ceb_node*)node->b[1])->b[1]) ? 'n' : 'l',
(node == node->b[1]) ? " dir=both" : "");
break;
case CEB_KT_MB:
break;
case CEB_KT_IM:
break;
case CEB_KT_ST:
printf(" \"%lx_n\" [label=\"%lx\\nlev=%d bit=%ld\\nkey=\\\"%s\\\"\" fillcolor=\"lightskyblue1\"%s];\n",
(long)node, (long)node, level, (long)pxor, NODEK(node, kofs)->str, (ctx == node) ? " color=red" : "");
printf(" \"%lx_n\" -> \"%lx_%c\" [label=\"L\" arrowsize=0.66 %s];\n",
(long)node, (long)node->b[0],
(lxor > pxor && ((struct ceb_node*)node->b[0])->b[0] != ((struct ceb_node*)node->b[0])->b[1]) ? 'n' : 'l',
(node == node->b[0]) ? " dir=both" : "");
printf(" \"%lx_n\" -> \"%lx_%c\" [label=\"R\" arrowsize=0.66 %s];\n",
(long)node, (long)node->b[1],
(rxor > pxor && ((struct ceb_node*)node->b[1])->b[0] != ((struct ceb_node*)node->b[1])->b[1]) ? 'n' : 'l',
(node == node->b[1]) ? " dir=both" : "");
break;
case CEB_KT_IS:
printf(" \"%lx_n\" [label=\"%lx\\nlev=%d bit=%ld\\nkey=\\\"%s\\\"\" fillcolor=\"lightskyblue1\"%s];\n",
(long)node, (long)node, level, (long)pxor, NODEK(node, kofs)->ptr, (ctx == node) ? " color=red" : "");
printf(" \"%lx_n\" -> \"%lx_%c\" [label=\"L\" arrowsize=0.66 %s];\n",
(long)node, (long)node->b[0],
(lxor > pxor && ((struct ceb_node*)node->b[0])->b[0] != ((struct ceb_node*)node->b[0])->b[1]) ? 'n' : 'l',
(node == node->b[0]) ? " dir=both" : "");
printf(" \"%lx_n\" -> \"%lx_%c\" [label=\"R\" arrowsize=0.66 %s];\n",
(long)node, (long)node->b[1],
(rxor > pxor && ((struct ceb_node*)node->b[1])->b[0] != ((struct ceb_node*)node->b[1])->b[1]) ? 'n' : 'l',
(node == node->b[1]) ? " dir=both" : "");
break;
}
}
/* dump a leaf */
__attribute__((unused))
static void cebu_default_dump_leaf(ptrdiff_t kofs, enum ceb_key_type key_type, const struct ceb_node *node, int level, const void *ctx)
{
unsigned long long int_key = 0;
uint64_t pxor;
switch (key_type) {
case CEB_KT_ADDR:
int_key = (uintptr_t)node;
break;
case CEB_KT_U32:
int_key = NODEK(node, kofs)->u32;
break;
case CEB_KT_U64:
int_key = NODEK(node, kofs)->u64;
break;
default:
break;
}
/* xor of the keys of the two lower branches */
pxor = _xor_branches(kofs, key_type, 0, 0, NULL,
node->b[0], node->b[1]);
switch (key_type) {
case CEB_KT_ADDR:
case CEB_KT_U32:
case CEB_KT_U64:
if (node->b[0] == node->b[1])
printf(" \"%lx_l\" [label=\"%lx\\nlev=%d\\nkey=%llu\\n\" fillcolor=\"green\"%s];\n",
(long)node, (long)node, level, int_key, (ctx == node) ? " color=red" : "");
else
printf(" \"%lx_l\" [label=\"%lx\\nlev=%d bit=%d\\nkey=%llu\\n\" fillcolor=\"yellow\"%s];\n",
(long)node, (long)node, level, flsnz(pxor) - 1, int_key, (ctx == node) ? " color=red" : "");
break;
case CEB_KT_MB:
break;
case CEB_KT_IM:
break;
case CEB_KT_ST:
if (node->b[0] == node->b[1])
printf(" \"%lx_l\" [label=\"%lx\\nlev=%d\\nkey=\\\"%s\\\"\\n\" fillcolor=\"green\"%s];\n",
(long)node, (long)node, level, NODEK(node, kofs)->str, (ctx == node) ? " color=red" : "");
else
printf(" \"%lx_l\" [label=\"%lx\\nlev=%d bit=%ld\\nkey=\\\"%s\\\"\\n\" fillcolor=\"yellow\"%s];\n",
(long)node, (long)node, level, (long)pxor, NODEK(node, kofs)->str, (ctx == node) ? " color=red" : "");
break;
case CEB_KT_IS:
if (node->b[0] == node->b[1])
printf(" \"%lx_l\" [label=\"%lx\\nlev=%d\\nkey=\\\"%s\\\"\\n\" fillcolor=\"green\"%s];\n",
(long)node, (long)node, level, NODEK(node, kofs)->ptr, (ctx == node) ? " color=red" : "");
else
printf(" \"%lx_l\" [label=\"%lx\\nlev=%d bit=%ld\\nkey=\\\"%s\\\"\\n\" fillcolor=\"yellow\"%s];\n",
(long)node, (long)node, level, (long)pxor, NODEK(node, kofs)->ptr, (ctx == node) ? " color=red" : "");
break;
}
}
/* Dumps a tree through the specified callbacks, falling back to the default
* callbacks above if left NULL.
*/
__attribute__((unused))
static const struct ceb_node *cebu_default_dump_tree(ptrdiff_t kofs, enum ceb_key_type key_type, struct ceb_node *const *root,
uint64_t pxor, const void *last, int level, const void *ctx,
void (*root_dump)(ptrdiff_t kofs, enum ceb_key_type key_type, struct ceb_node *const *root, const void *ctx),
void (*node_dump)(ptrdiff_t kofs, enum ceb_key_type key_type, const struct ceb_node *node, int level, const void *ctx),
void (*leaf_dump)(ptrdiff_t kofs, enum ceb_key_type key_type, const struct ceb_node *node, int level, const void *ctx))
{
const struct ceb_node *node = *root;
uint64_t xor;
if (!node) /* empty tree */
return node;
if (!root_dump)
root_dump = cebu_default_dump_root;
if (!node_dump)
node_dump = cebu_default_dump_node;
if (!leaf_dump)
leaf_dump = cebu_default_dump_leaf;
if (!level) {
/* dump the first arrow */
root_dump(kofs, key_type, root, ctx);
}
/* regular nodes, all branches are canonical */
if (node->b[0] == node->b[1]) {
/* first inserted leaf */
leaf_dump(kofs, key_type, node, level, ctx);
return node;
}
xor = _xor_branches(kofs, key_type, 0, 0, NULL,
node->b[0], node->b[1]);
switch (key_type) {
case CEB_KT_ADDR:
case CEB_KT_U32:
case CEB_KT_U64:
if (pxor && xor >= pxor) {
/* that's a leaf for a scalar type */
leaf_dump(kofs, key_type, node, level, ctx);
return node;
}
break;
default:
if (pxor && xor <= pxor) {
/* that's a leaf for a non-scalar type */
leaf_dump(kofs, key_type, node, level, ctx);
return node;
}
break;
}
/* that's a regular node */
node_dump(kofs, key_type, node, level, ctx);
last = cebu_default_dump_tree(kofs, key_type, &node->b[0], xor, last, level + 1, ctx, root_dump, node_dump, leaf_dump);
return cebu_default_dump_tree(kofs, key_type, &node->b[1], xor, last, level + 1, ctx, root_dump, node_dump, leaf_dump);
}
#endif /* _CEBTREE_PRV_H */
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