diff --git a/accel-pppd/CMakeLists.txt b/accel-pppd/CMakeLists.txt index d82f8d277c853b83893de702e9daf21a9be760ba..aa13e55038f8c24454359fbe6d42afdf6193aff0 100644 --- a/accel-pppd/CMakeLists.txt +++ b/accel-pppd/CMakeLists.txt @@ -91,6 +91,7 @@ ADD_EXECUTABLE(accel-pppd iprange.c utils.c + rbtree.c log.c main.c diff --git a/accel-pppd/ctrl/ipoe/arp.c b/accel-pppd/ctrl/ipoe/arp.c index ebf05c7b5649068df0218820dfda075c0d58f1f7..6c647f1c674821b5daa0d65db9ffea265d05b76e 100644 --- a/accel-pppd/ctrl/ipoe/arp.c +++ b/accel-pppd/ctrl/ipoe/arp.c @@ -6,6 +6,7 @@ #include #include #include +#include #include #include #include @@ -17,7 +18,9 @@ #include "list.h" #include "triton.h" +#include "mempool.h" #include "log.h" +#include "rbtree.h" #include "ipoe.h" @@ -35,20 +38,34 @@ struct _arphdr { __be32 ar_tpa; } __packed; -static int arp_read(struct triton_md_handler_t *h) +struct arp_node { + struct rb_node node; + struct ipoe_serv *ipoe; +}; + +struct arp_tree { + pthread_mutex_t lock; + struct rb_root root; +}; + +static mempool_t arp_pool; +static mempool_t arp_hdr_pool; + +#define HASH_BITS 0xff +static struct arp_tree *arp_tree; + +static struct triton_md_handler_t arp_hnd; + +static void arp_ctx_read(struct _arphdr *ah) { - struct arp_serv *s = container_of(h, typeof(*s), h); - char buf[128]; - int n; - struct _arphdr *ah = (struct _arphdr *)buf; struct _arphdr ah2; - struct sockaddr_ll src, dst; - socklen_t slen = sizeof(src); - struct ipoe_session *ses, *ses1, *ses2; + struct ipoe_session *ses, *ses1 = NULL, *ses2 = NULL; + struct ipoe_serv *ipoe = container_of(triton_context_self(), typeof(*ipoe), ctx); + struct sockaddr_ll dst; memset(&dst, 0, sizeof(dst)); dst.sll_family = AF_PACKET; - dst.sll_ifindex = s->ipoe->ifindex; + dst.sll_ifindex = ipoe->ifindex; dst.sll_protocol = htons(ETH_P_ARP); ah2.ar_hrd = htons(ARPHRD_ETHER); @@ -57,15 +74,78 @@ static int arp_read(struct triton_md_handler_t *h) ah2.ar_pln = 4; ah2.ar_op = htons(ARPOP_REPLY); + pthread_mutex_lock(&ipoe->lock); + list_for_each_entry(ses, &ipoe->sessions, entry) { + if (ses->yiaddr == ah->ar_spa) { + ses1 = ses; + if (ses->ses.state != AP_STATE_ACTIVE) + break; + } + + if (ses->yiaddr == ah->ar_tpa) { + ses2 = ses; + if (ses->ses.state != AP_STATE_ACTIVE) + break; + } + + if (ses1 && ses2) + break; + } + + if (!ses1 || (ses1->ses.state != AP_STATE_ACTIVE) || + (ses2 && ses2->ses.state != AP_STATE_ACTIVE)) { + pthread_mutex_unlock(&ipoe->lock); + goto out; + } + + if (ses2) { + if (ipoe->opt_arp == 1 || ses1 == ses2) { + pthread_mutex_unlock(&ipoe->lock); + goto out; + } + + if (ipoe->opt_arp == 2) + memcpy(ah2.ar_sha, ses2->hwaddr, ETH_ALEN); + else + memcpy(ah2.ar_sha, ipoe->hwaddr, ETH_ALEN); + } else + memcpy(ah2.ar_sha, ipoe->hwaddr, ETH_ALEN); + + pthread_mutex_unlock(&ipoe->lock); + + memcpy(dst.sll_addr, ah->ar_sha, ETH_ALEN); + memcpy(ah2.ar_tha, ah->ar_sha, ETH_ALEN); + ah2.ar_spa = ah->ar_tpa; + ah2.ar_tpa = ah->ar_spa; + + sendto(arp_hnd.fd, &ah2, sizeof(ah2), MSG_DONTWAIT, (struct sockaddr *)&dst, sizeof(dst)); + +out: + mempool_free(ah); +} + +static int arp_read(struct triton_md_handler_t *h) +{ + int r, i; + struct _arphdr *ah = NULL; + struct sockaddr_ll src; + socklen_t slen = sizeof(src); + struct arp_tree *t; + struct arp_node *n; + struct rb_node **p, *parent; + while (1) { - n = recvfrom(h->fd, buf, sizeof(buf), MSG_DONTWAIT, (struct sockaddr *)&src, &slen); - if (n < 0) { + if (!ah) + ah = mempool_alloc(arp_hdr_pool); + + r = recvfrom(h->fd, ah, sizeof(*ah), MSG_DONTWAIT, (struct sockaddr *)&src, &slen); + if (r < 0) { if (errno == EAGAIN) break; continue; } - if (n < sizeof(*ah)) + if (r < sizeof(*ah)) continue; if (ah->ar_op != htons(ARPOP_REQUEST)) @@ -83,60 +163,44 @@ static int arp_read(struct triton_md_handler_t *h) if (memcmp(ah->ar_sha, src.sll_addr, ETH_ALEN)) continue; - ses1 = ses2 = NULL; - pthread_mutex_lock(&s->ipoe->lock); - list_for_each_entry(ses, &s->ipoe->sessions, entry) { - if (ses->yiaddr == ah->ar_spa) { - ses1 = ses; - if (ses->ses.state != AP_STATE_ACTIVE) - break; - } - if (ses->yiaddr == ah->ar_tpa) { - ses2 = ses; - if (ses->ses.state != AP_STATE_ACTIVE) - break; - } - if (ses1 && ses2) - break; - } + t = &arp_tree[src.sll_ifindex & HASH_BITS]; - if (!ses1 || (ses1->ses.state != AP_STATE_ACTIVE) || - (ses2 && ses2->ses.state != AP_STATE_ACTIVE)) { - pthread_mutex_unlock(&s->ipoe->lock); - continue; - } + parent = NULL; - if (ses2) { - if (s->ipoe->opt_arp == 1 || ses1 == ses2) { - pthread_mutex_unlock(&s->ipoe->lock); - continue; - } - if (s->ipoe->opt_arp == 2) - memcpy(ah2.ar_sha, ses2->hwaddr, ETH_ALEN); - else - memcpy(ah2.ar_sha, s->ipoe->hwaddr, ETH_ALEN); - } else - memcpy(ah2.ar_sha, s->ipoe->hwaddr, ETH_ALEN); + pthread_mutex_lock(&t->lock); + + p = &t->root.rb_node; - pthread_mutex_unlock(&s->ipoe->lock); + while (*p) { + parent = *p; + n = rb_entry(parent, typeof(*n), node); + i = n->ipoe->ifindex; - memcpy(dst.sll_addr, ah->ar_sha, ETH_ALEN); - memcpy(ah2.ar_tha, ah->ar_sha, ETH_ALEN); - ah2.ar_spa = ah->ar_tpa; - ah2.ar_tpa = ah->ar_spa; + if (src.sll_ifindex < i) + p = &(*p)->rb_left; + else if (src.sll_ifindex > i) + p = &(*p)->rb_right; + else { + triton_context_call(&n->ipoe->ctx, (triton_event_func)arp_ctx_read, ah); + ah = NULL; + break; + } + } - sendto(h->fd, &ah2, sizeof(ah2), MSG_DONTWAIT, (struct sockaddr *)&dst, sizeof(dst)); + pthread_mutex_unlock(&t->lock); } + mempool_free(ah); + return 0; } -struct arp_serv *arpd_start(struct ipoe_serv *ipoe) +void *arpd_start(struct ipoe_serv *ipoe) { - int sock; - struct sockaddr_ll addr; - struct arp_serv *s; - int f = 1, fd; + struct rb_node **p, *parent = NULL; + struct arp_node *n; + struct arp_tree *t; + int fd, ifindex = ipoe->ifindex, i; char fname[1024]; sprintf(fname, "/proc/sys/net/ipv4/conf/%s/proxy_arp", ipoe->ifname); @@ -147,46 +211,115 @@ struct arp_serv *arpd_start(struct ipoe_serv *ipoe) close(fd); } + t = &arp_tree[ifindex & HASH_BITS]; + + pthread_mutex_lock(&t->lock); + + p = &t->root.rb_node; + + while (*p) { + parent = *p; + n = rb_entry(parent, typeof(*n), node); + i = n->ipoe->ifindex; + + if (ifindex < i) + p = &(*p)->rb_left; + else if (ifindex > i) + p = &(*p)->rb_right; + else { + pthread_mutex_unlock(&t->lock); + log_ppp_error("arp: attempt to add duplicate ifindex\n"); + return NULL; + } + } + + n = mempool_alloc(arp_pool); + if (!n) { + pthread_mutex_unlock(&t->lock); + log_emerg("out of memory\n"); + return NULL; + } + + n->ipoe = ipoe; + + rb_link_node(&n->node, parent, p); + rb_insert_color(&n->node, &t->root); + + pthread_mutex_unlock(&t->lock); + + return n; +} + +void arpd_stop(void *arg) +{ + struct arp_node *n = arg; + struct arp_tree *t = &arp_tree[n->ipoe->ifindex]; + + pthread_mutex_lock(&t->lock); + rb_erase(&n->node, &t->root); + pthread_mutex_unlock(&t->lock); + + mempool_free(n); +} + +static void arp_close(struct triton_context_t *ctx); + +static struct triton_context_t arp_ctx = { + .close = arp_close, +}; + +static struct triton_md_handler_t arp_hnd = { + .read = arp_read, +}; + +static void arp_close(struct triton_context_t *ctx) +{ + triton_md_unregister_handler(&arp_hnd, 1); + triton_context_unregister(ctx); +} + +static void init() +{ + struct sockaddr_ll addr; + int i, f = 1; + int sock; + + arp_pool = mempool_create(sizeof(struct arp_node)); + arp_hdr_pool = mempool_create(sizeof(struct _arphdr)); + + arp_tree = malloc((HASH_BITS + 1) * sizeof(struct arp_tree)); + for (i = 0; i <= HASH_BITS; i++) { + pthread_mutex_init(&arp_tree[i].lock, NULL); + arp_tree[i].root = RB_ROOT; + } + sock = socket(PF_PACKET, SOCK_DGRAM, 0); if (sock < 0) { - log_error("ipoe: arp: socket: %s\n", strerror(errno)); - return NULL; + log_error("arp: socket: %s\n", strerror(errno)); + return; } memset(&addr, 0, sizeof(addr)); addr.sll_family = AF_PACKET; addr.sll_protocol = htons(ETH_P_ARP); - addr.sll_ifindex = ipoe->ifindex; - if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &f, sizeof(f))) { - log_error("ipoe: setsockopt(SO_BROADCAST): %s\n", strerror(errno)); - close(sock); - return NULL; - } + setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &f, sizeof(f)); if (bind(sock, (struct sockaddr *)&addr, sizeof(addr))) { - log_error("ipoe: arp: bind: %s\n", strerror(errno)); + log_error("arp: bind: %s\n", strerror(errno)); close(sock); - return NULL; + return; } - s = _malloc(sizeof(*s)); - s->ipoe = ipoe; - s->h.fd = sock; - s->h.read = arp_read; - fcntl(sock, F_SETFL, O_NONBLOCK); - fcntl(sock, F_SETFD, fcntl(sock, F_GETFD) | FD_CLOEXEC); + fcntl(sock, F_SETFD, FD_CLOEXEC); - triton_md_register_handler(&ipoe->ctx, &s->h); - triton_md_enable_handler(&s->h, MD_MODE_READ); + arp_hnd.fd = sock; - return s; -} - -void arpd_stop(struct arp_serv *arp) -{ - triton_md_unregister_handler(&arp->h, 1); - _free(arp); + triton_context_register(&arp_ctx, NULL); + triton_md_register_handler(&arp_ctx, &arp_hnd); + triton_md_enable_handler(&arp_hnd, MD_MODE_READ); + triton_context_wakeup(&arp_ctx); } +DEFINE_INIT(1, init); diff --git a/accel-pppd/ctrl/ipoe/ipoe.h b/accel-pppd/ctrl/ipoe/ipoe.h index c27acdd7c5695db42cbf735c2c73de35f39f4b05..f14bb5dc3efb99fb9f2482794816156da1192bab 100644 --- a/accel-pppd/ctrl/ipoe/ipoe.h +++ b/accel-pppd/ctrl/ipoe/ipoe.h @@ -17,8 +17,6 @@ #define ETH_ALEN 6 #endif -struct arp_serv; - struct ipoe_serv { struct list_head entry; struct triton_context_t ctx; @@ -29,7 +27,7 @@ struct ipoe_serv { struct list_head addr_list; struct dhcpv4_serv *dhcpv4; struct dhcpv4_relay *dhcpv4_relay; - struct arp_serv *arp; + void *arp; struct list_head disc_list; struct list_head req_list; struct triton_timer_t disc_timer; @@ -105,11 +103,6 @@ struct ipoe_session_info { uint32_t peer_addr; }; -struct arp_serv { - struct triton_md_handler_t h; - struct ipoe_serv *ipoe; -}; - #ifdef USE_LUA char *ipoe_lua_get_username(struct ipoe_session *, const char *func); #endif @@ -138,8 +131,8 @@ int ipoe_nl_del_vlan_mon(int ifindex); int ipoe_nl_add_exclude(uint32_t addr, int mask); void ipoe_nl_del_exclude(uint32_t addr); -struct arp_serv *arpd_start(struct ipoe_serv *ipoe); -void arpd_stop(struct arp_serv *arp); +void *arpd_start(struct ipoe_serv *ipoe); +void arpd_stop(void *arp); #endif diff --git a/accel-pppd/include/rbtree.h b/accel-pppd/include/rbtree.h new file mode 100644 index 0000000000000000000000000000000000000000..c9fe6b4200707d69c09a67e0184c7400bd1852a8 --- /dev/null +++ b/accel-pppd/include/rbtree.h @@ -0,0 +1,179 @@ +/* + Red Black Trees + (C) 1999 Andrea Arcangeli + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + + linux/include/linux/rbtree.h + + To use rbtrees you'll have to implement your own insert and search cores. + This will avoid us to use callbacks and to drop drammatically performances. + I know it's not the cleaner way, but in C (not in C++) to get + performances and genericity... + + Some example of insert and search follows here. The search is a plain + normal search over an ordered tree. The insert instead must be implemented + int two steps: as first thing the code must insert the element in + order as a red leaf in the tree, then the support library function + rb_insert_color() must be called. Such function will do the + not trivial work to rebalance the rbtree if necessary. + +----------------------------------------------------------------------- +static inline struct page * rb_search_page_cache(struct inode * inode, + unsigned long offset) +{ + struct rb_node * n = inode->i_rb_page_cache.rb_node; + struct page * page; + + while (n) + { + page = rb_entry(n, struct page, rb_page_cache); + + if (offset < page->offset) + n = n->rb_left; + else if (offset > page->offset) + n = n->rb_right; + else + return page; + } + return NULL; +} + +static inline struct page * __rb_insert_page_cache(struct inode * inode, + unsigned long offset, + struct rb_node * node) +{ + struct rb_node ** p = &inode->i_rb_page_cache.rb_node; + struct rb_node * parent = NULL; + struct page * page; + + while (*p) + { + parent = *p; + page = rb_entry(parent, struct page, rb_page_cache); + + if (offset < page->offset) + p = &(*p)->rb_left; + else if (offset > page->offset) + p = &(*p)->rb_right; + else + return page; + } + + rb_link_node(node, parent, p); + + return NULL; +} + +static inline struct page * rb_insert_page_cache(struct inode * inode, + unsigned long offset, + struct rb_node * node) +{ + struct page * ret; + if ((ret = __rb_insert_page_cache(inode, offset, node))) + goto out; + rb_insert_color(node, &inode->i_rb_page_cache); + out: + return ret; +} +----------------------------------------------------------------------- +*/ + +#ifndef _LINUX_RBTREE_H +#define _LINUX_RBTREE_H + +#include + +#undef offsetof +#ifdef __compiler_offsetof +#define offsetof(TYPE,MEMBER) __compiler_offsetof(TYPE,MEMBER) +#else +#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) +#endif + +/** + * container_of - cast a member of a structure out to the containing structure + * @ptr: the pointer to the member. + * @type: the type of the container struct this is embedded in. + * @member: the name of the member within the struct. + * + */ +#define container_of(ptr, type, member) ({ \ + const typeof( ((type *)0)->member ) *__mptr = (ptr); \ + (type *)( (char *)__mptr - offsetof(type,member) );}) + + +struct rb_node +{ + unsigned long rb_parent_color; +#define RB_RED 0 +#define RB_BLACK 1 + struct rb_node *rb_right; + struct rb_node *rb_left; +} __attribute__((aligned(sizeof(long)))); + /* The alignment might seem pointless, but allegedly CRIS needs it */ + +struct rb_root +{ + struct rb_node *rb_node; +}; + + +#define rb_parent(r) ((struct rb_node *)((r)->rb_parent_color & ~3)) +#define rb_color(r) ((r)->rb_parent_color & 1) +#define rb_is_red(r) (!rb_color(r)) +#define rb_is_black(r) rb_color(r) +#define rb_set_red(r) do { (r)->rb_parent_color &= ~1; } while (0) +#define rb_set_black(r) do { (r)->rb_parent_color |= 1; } while (0) + +static inline void rb_set_parent(struct rb_node *rb, struct rb_node *p) +{ + rb->rb_parent_color = (rb->rb_parent_color & 3) | (unsigned long)p; +} +static inline void rb_set_color(struct rb_node *rb, int color) +{ + rb->rb_parent_color = (rb->rb_parent_color & ~1) | color; +} + +#define RB_ROOT (struct rb_root) { NULL, } +#define rb_entry(ptr, type, member) container_of(ptr, type, member) + +#define RB_EMPTY_ROOT(root) ((root)->rb_node == NULL) +#define RB_EMPTY_NODE(node) (rb_parent(node) == node) +#define RB_CLEAR_NODE(node) (rb_set_parent(node, node)) + +extern void rb_insert_color(struct rb_node *, struct rb_root *); +extern void rb_erase(struct rb_node *, struct rb_root *); + +/* Find logical next and previous nodes in a tree */ +extern struct rb_node *rb_next(struct rb_node *); +extern struct rb_node *rb_prev(struct rb_node *); +extern struct rb_node *rb_first(struct rb_root *); +extern struct rb_node *rb_last(struct rb_root *); + +/* Fast replacement of a single node without remove/rebalance/add/rebalance */ +extern void rb_replace_node(struct rb_node *victim, struct rb_node *new, + struct rb_root *root); + +static inline void rb_link_node(struct rb_node * node, struct rb_node * parent, + struct rb_node ** rb_link) +{ + node->rb_parent_color = (unsigned long )parent; + node->rb_left = node->rb_right = NULL; + + *rb_link = node; +} + +#endif /* _LINUX_RBTREE_H */ diff --git a/accel-pppd/rbtree.c b/accel-pppd/rbtree.c new file mode 100644 index 0000000000000000000000000000000000000000..11487fac065b69a1272a0fd8d5d9c5cbe0c1d4d1 --- /dev/null +++ b/accel-pppd/rbtree.c @@ -0,0 +1,392 @@ +/* + Red Black Trees + (C) 1999 Andrea Arcangeli + (C) 2002 David Woodhouse + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + + linux/lib/rbtree.c +*/ + +#include "triton.h" +#include "rbtree.h" + +static void __rb_rotate_left(struct rb_node *node, struct rb_root *root) +{ + struct rb_node *right = node->rb_right; + struct rb_node *parent = rb_parent(node); + + if ((node->rb_right = right->rb_left)) + rb_set_parent(right->rb_left, node); + right->rb_left = node; + + rb_set_parent(right, parent); + + if (parent) + { + if (node == parent->rb_left) + parent->rb_left = right; + else + parent->rb_right = right; + } + else + root->rb_node = right; + rb_set_parent(node, right); +} + +static void __rb_rotate_right(struct rb_node *node, struct rb_root *root) +{ + struct rb_node *left = node->rb_left; + struct rb_node *parent = rb_parent(node); + + if ((node->rb_left = left->rb_right)) + rb_set_parent(left->rb_right, node); + left->rb_right = node; + + rb_set_parent(left, parent); + + if (parent) + { + if (node == parent->rb_right) + parent->rb_right = left; + else + parent->rb_left = left; + } + else + root->rb_node = left; + rb_set_parent(node, left); +} + +void __export rb_insert_color(struct rb_node *node, struct rb_root *root) +{ + struct rb_node *parent, *gparent; + + while ((parent = rb_parent(node)) && rb_is_red(parent)) + { + gparent = rb_parent(parent); + + if (parent == gparent->rb_left) + { + { + register struct rb_node *uncle = gparent->rb_right; + if (uncle && rb_is_red(uncle)) + { + rb_set_black(uncle); + rb_set_black(parent); + rb_set_red(gparent); + node = gparent; + continue; + } + } + + if (parent->rb_right == node) + { + register struct rb_node *tmp; + __rb_rotate_left(parent, root); + tmp = parent; + parent = node; + node = tmp; + } + + rb_set_black(parent); + rb_set_red(gparent); + __rb_rotate_right(gparent, root); + } else { + { + register struct rb_node *uncle = gparent->rb_left; + if (uncle && rb_is_red(uncle)) + { + rb_set_black(uncle); + rb_set_black(parent); + rb_set_red(gparent); + node = gparent; + continue; + } + } + + if (parent->rb_left == node) + { + register struct rb_node *tmp; + __rb_rotate_right(parent, root); + tmp = parent; + parent = node; + node = tmp; + } + + rb_set_black(parent); + rb_set_red(gparent); + __rb_rotate_left(gparent, root); + } + } + + rb_set_black(root->rb_node); +} + +static void __rb_erase_color(struct rb_node *node, struct rb_node *parent, + struct rb_root *root) +{ + struct rb_node *other; + + while ((!node || rb_is_black(node)) && node != root->rb_node) + { + if (parent->rb_left == node) + { + other = parent->rb_right; + if (rb_is_red(other)) + { + rb_set_black(other); + rb_set_red(parent); + __rb_rotate_left(parent, root); + other = parent->rb_right; + } + if ((!other->rb_left || rb_is_black(other->rb_left)) && + (!other->rb_right || rb_is_black(other->rb_right))) + { + rb_set_red(other); + node = parent; + parent = rb_parent(node); + } + else + { + if (!other->rb_right || rb_is_black(other->rb_right)) + { + struct rb_node *o_left; + if ((o_left = other->rb_left)) + rb_set_black(o_left); + rb_set_red(other); + __rb_rotate_right(other, root); + other = parent->rb_right; + } + rb_set_color(other, rb_color(parent)); + rb_set_black(parent); + if (other->rb_right) + rb_set_black(other->rb_right); + __rb_rotate_left(parent, root); + node = root->rb_node; + break; + } + } + else + { + other = parent->rb_left; + if (rb_is_red(other)) + { + rb_set_black(other); + rb_set_red(parent); + __rb_rotate_right(parent, root); + other = parent->rb_left; + } + if ((!other->rb_left || rb_is_black(other->rb_left)) && + (!other->rb_right || rb_is_black(other->rb_right))) + { + rb_set_red(other); + node = parent; + parent = rb_parent(node); + } + else + { + if (!other->rb_left || rb_is_black(other->rb_left)) + { + register struct rb_node *o_right; + if ((o_right = other->rb_right)) + rb_set_black(o_right); + rb_set_red(other); + __rb_rotate_left(other, root); + other = parent->rb_left; + } + rb_set_color(other, rb_color(parent)); + rb_set_black(parent); + if (other->rb_left) + rb_set_black(other->rb_left); + __rb_rotate_right(parent, root); + node = root->rb_node; + break; + } + } + } + if (node) + rb_set_black(node); +} + +void __export rb_erase(struct rb_node *node, struct rb_root *root) +{ + struct rb_node *child, *parent; + int color; + + if (!node->rb_left) + child = node->rb_right; + else if (!node->rb_right) + child = node->rb_left; + else + { + struct rb_node *old = node, *left; + + node = node->rb_right; + while ((left = node->rb_left) != NULL) + node = left; + child = node->rb_right; + parent = rb_parent(node); + color = rb_color(node); + + if (child) + rb_set_parent(child, parent); + if (parent == old) { + parent->rb_right = child; + parent = node; + } else + parent->rb_left = child; + + node->rb_parent_color = old->rb_parent_color; + node->rb_right = old->rb_right; + node->rb_left = old->rb_left; + + if (rb_parent(old)) + { + if (rb_parent(old)->rb_left == old) + rb_parent(old)->rb_left = node; + else + rb_parent(old)->rb_right = node; + } else + root->rb_node = node; + + rb_set_parent(old->rb_left, node); + if (old->rb_right) + rb_set_parent(old->rb_right, node); + goto color; + } + + parent = rb_parent(node); + color = rb_color(node); + + if (child) + rb_set_parent(child, parent); + if (parent) + { + if (parent->rb_left == node) + parent->rb_left = child; + else + parent->rb_right = child; + } + else + root->rb_node = child; + + color: + if (color == RB_BLACK) + __rb_erase_color(child, parent, root); +} + +/* + * This function returns the first node (in sort order) of the tree. + */ +struct rb_node __export *rb_first(struct rb_root *root) +{ + struct rb_node *n; + + n = root->rb_node; + if (!n) + return NULL; + while (n->rb_left) + n = n->rb_left; + return n; +} + +struct rb_node __export *rb_last(struct rb_root *root) +{ + struct rb_node *n; + + n = root->rb_node; + if (!n) + return NULL; + while (n->rb_right) + n = n->rb_right; + return n; +} + +struct rb_node __export *rb_next(struct rb_node *node) +{ + struct rb_node *parent; + + if (rb_parent(node) == node) + return NULL; + + /* If we have a right-hand child, go down and then left as far + as we can. */ + if (node->rb_right) { + node = node->rb_right; + while (node->rb_left) + node=node->rb_left; + return node; + } + + /* No right-hand children. Everything down and left is + smaller than us, so any 'next' node must be in the general + direction of our parent. Go up the tree; any time the + ancestor is a right-hand child of its parent, keep going + up. First time it's a left-hand child of its parent, said + parent is our 'next' node. */ + while ((parent = rb_parent(node)) && node == parent->rb_right) + node = parent; + + return parent; +} + +struct rb_node __export *rb_prev(struct rb_node *node) +{ + struct rb_node *parent; + + if (rb_parent(node) == node) + return NULL; + + /* If we have a left-hand child, go down and then right as far + as we can. */ + if (node->rb_left) { + node = node->rb_left; + while (node->rb_right) + node=node->rb_right; + return node; + } + + /* No left-hand children. Go up till we find an ancestor which + is a right-hand child of its parent */ + while ((parent = rb_parent(node)) && node == parent->rb_left) + node = parent; + + return parent; +} + + +void __export rb_replace_node(struct rb_node *victim, struct rb_node *new, + struct rb_root *root) +{ + struct rb_node *parent = rb_parent(victim); + + /* Set the surrounding nodes to point to the replacement */ + if (parent) { + if (victim == parent->rb_left) + parent->rb_left = new; + else + parent->rb_right = new; + } else { + root->rb_node = new; + } + if (victim->rb_left) + rb_set_parent(victim->rb_left, new); + if (victim->rb_right) + rb_set_parent(victim->rb_right, new); + + /* Copy the pointers/colour from the victim to the replacement */ + *new = *victim; +} +