pike.git/src/rbtree.c:401b710e041c53f60569bc784a3b6ea8b229a188

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1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 /* || This file is part of Pike. For copyright information see COPYRIGHT. || Pike is distributed under GPL, LGPL and MPL. See the file COPYING || for more information. || $Id: rbtree.c,v 1.14 2002/12/05 20:13:04 mast Exp $ */ /* An implementation of a threaded red/black balanced binary tree. * * Created 2001-04-27 by Martin Stjernholm <mast@lysator.liu.se> */ #include "global.h" RCSID("$Id: rbtree.c,v 1.14 2002/12/05 20:13:04 mast Exp $"); #include "interpret.h" #include "pike_error.h" #include "rbtree_low.h" #include <assert.h> #include <stdlib.h> #if defined (PIKE_DEBUG) || defined (TEST_MULTISET) DECLSPEC(noreturn) static void debug_rb_fatal ( struct rb_node_hdr *tree, const char *fmt, ...) ATTRIBUTE((noreturn, format (printf, 2, 3))); #define rb_fatal \ (fprintf (stderr, "%s:%d: Fatal in rbtree: ", __FILE__, __LINE__), \ debug_rb_fatal) DECLSPEC(noreturn) static void debug_custom_rb_fatal ( struct rb_node_hdr *tree, dump_data_fn *dump_data, void *extra, const char *fmt, ...) ATTRIBUTE((noreturn, format (printf, 4, 5))); #define custom_rb_fatal \ (fprintf (stderr, "%s:%d: Fatal in rbtree: ", __FILE__, __LINE__), \ debug_custom_rb_fatal) #endif void rbstack_push (struct rbstack_ptr *rbstack, struct rb_node_hdr *node) { struct rbstack_slice *new = ALLOC_STRUCT (rbstack_slice); new->up = rbstack->slice; new->stack[0] = node; #ifdef RB_STATS rbstack_slice_allocs++; new->depth = rbstack->slice->depth; new->maxdepth = rbstack->slice->maxdepth; #endif rbstack->slice = new; rbstack->ssp = 1; } void rbstack_pop (struct rbstack_ptr *rbstack) { struct rbstack_slice *old = rbstack->slice; rbstack->slice = old->up; #ifdef RB_STATS rbstack->slice->maxdepth = old->maxdepth; #endif xfree (old); rbstack->ssp = STACK_SLICE_SIZE; } void rbstack_up (struct rbstack_ptr *rbstack) { rbstack->slice = rbstack->slice->up; rbstack->ssp = STACK_SLICE_SIZE; } void rbstack_up_to_root (struct rbstack_ptr *rbstack) { struct rbstack_slice *up; while ((up = rbstack->slice->up)) rbstack->slice = up; rbstack->ssp = 0; } void rbstack_free (struct rbstack_ptr *rbstack) { struct rbstack_slice *ptr = rbstack->slice; do { struct rbstack_slice *old = ptr; ptr = ptr->up; #ifdef RB_STATS ptr->maxdepth = old->maxdepth; #endif xfree (old); } while (ptr->up); rbstack->slice = ptr; rbstack->ssp = 0; } /* Inserts the given node at *pos and advances *pos. *top is the top * of the stack, which also is advanced to keep track of the top. */ void rbstack_insert (struct rbstack_ptr *top, struct rbstack_ptr *pos, struct rb_node_hdr *node) { struct rbstack_ptr rbp1 = *top, rbp2 = *top, rbpos = *pos; RBSTACK_PUSH (rbp2, NULL); *top = rbp2; while (rbp1.ssp != rbpos.ssp || rbp1.slice != rbpos.slice) { rbp2.slice->stack[--rbp2.ssp] = rbp1.slice->stack[--rbp1.ssp]; if (!rbp2.ssp) rbp2.slice = rbp1.slice, rbp2.ssp = STACK_SLICE_SIZE; if (!rbp1.ssp) { if (rbp1.slice->up) rbstack_up (&rbp1); #ifdef PIKE_DEBUG else if (rbp1.ssp != rbpos.ssp || rbp1.slice != rbpos.slice) Pike_fatal ("Didn't find the given position on the stack.\n"); #endif } } RBSTACK_POKE (rbp2, node); *pos = rbp2; } #if 0 /* Disabled since these aren't tested and not currently used. */ void rbstack_assign (struct rbstack_ptr *target, struct rbstack_ptr *source) { struct rbstack_slice *src_slice = source->slice; struct rbstack_slice *tgt_slice = target->slice; #ifdef PIKE_DEBUG if (target->ssp) Pike_fatal ("target rbstack not empty.\n"); #endif target->ssp = source->ssp; source->ssp = 0; if (src_slice->up) { struct rbstack_slice *prev_slice; target->slice = src_slice; do { prev_slice = src_slice; src_slice = src_slice->up; } while (src_slice->up); MEMCPY ((char *) &tgt_slice->stack, (char *) &src_slice->stack, STACK_SLICE_SIZE * sizeof (struct rb_node_hdr *)); prev_slice->up = tgt_slice; source->slice = src_slice; } else { MEMCPY ((char *) &tgt_slice->stack, (char *) &src_slice->stack, target->ssp * sizeof (struct rb_node_hdr *)); #ifdef RB_STATS tgt_slice->maxdepth = src_slice->maxdepth; tgt_slice->depth = src_slice->depth; #endif } } void rbstack_copy (struct rbstack_ptr *target, struct rbstack_ptr *source) { struct rbstack_slice *src_slice = source->slice; struct rbstack_slice *tgt_stack_slice = target->slice; size_t ssp = source->ssp; #ifdef PIKE_DEBUG if (target->ssp) Pike_fatal ("target rbstack not empty.\n"); #endif target->ssp = ssp; if (src_slice->up) { struct rbstack_slice *tgt_slice = target->slice = ALLOC_STRUCT (rbstack_slice); #ifdef RB_STATS rbstack_slice_allocs++; #endif MEMCPY ((char *) &tgt_slice->stack, (char *) &src_slice->stack, ssp * sizeof (struct rb_node_hdr *)); ssp = STACK_SLICE_SIZE; while ((src_slice = src_slice->up)->up) { tgt_slice->up = ALLOC_STRUCT (rbstack_slice); tgt_slice = tgt_slice->up; #ifdef RB_STATS rbstack_slice_allocs++; #endif MEMCPY ((char *) &tgt_slice->stack, (char *) &src_slice->stack, STACK_SLICE_SIZE * sizeof (struct rb_node_hdr *)); } tgt_slice->up = tgt_stack_slice; } MEMCPY ((char *) &tgt_stack_slice->stack, (char *) &src_slice->stack, ssp * sizeof (struct rb_node_hdr *)); #ifdef RB_STATS target->slice->maxdepth = target->slice->depth = source->slice->depth; #endif } #endif /* Not tested or used. */ /* Offsets all the rb_node_hdr pointers in rbstack from their offsets * relative oldbase to the same relative newbase. Useful if the memory * block containing the tree has been moved. */ void rbstack_shift (struct rbstack_ptr rbstack, struct rb_node_hdr *oldbase, struct rb_node_hdr *newbase) { struct rb_node_hdr *node; while ((node = RBSTACK_PEEK (rbstack))) { rbstack.slice->stack[rbstack.ssp - 1] = (struct rb_node_hdr *) ((char *) node - (char *) oldbase + (char *) newbase); RBSTACK_UP_IGNORE (rbstack); } } /* Each of these step functions is O(log n), but when used to loop * through a tree they still sum up to O(n) since every node is * visited at most twice. */ PMOD_EXPORT inline struct rb_node_hdr *rb_first (struct rb_node_hdr *root) { DO_IF_RB_STATS (rb_num_sidesteps++; rb_num_sidestep_ops++); if (root) while (root->prev) { root = root->prev; DO_IF_RB_STATS (rb_num_sidestep_ops++); } return root; } PMOD_EXPORT inline struct rb_node_hdr *rb_last (struct rb_node_hdr *root) { DO_IF_RB_STATS (rb_num_sidesteps++; rb_num_sidestep_ops++); if (root) while (root->next) { root = root->next; DO_IF_RB_STATS (rb_num_sidestep_ops++); } return root; } PMOD_EXPORT inline struct rb_node_hdr *rb_link_prev (struct rb_node_hdr *node) { node = node->prev; DO_IF_RB_STATS (rb_num_sidestep_ops++); while (!(node->flags & RB_THREAD_NEXT)) { node = node->next; DO_IF_RB_STATS (rb_num_sidestep_ops++); } return node; } PMOD_EXPORT inline struct rb_node_hdr *rb_link_next (struct rb_node_hdr *node) { node = node->next; DO_IF_RB_STATS (rb_num_sidestep_ops++); while (!(node->flags & RB_THREAD_PREV)) { node = node->prev; DO_IF_RB_STATS (rb_num_sidestep_ops++); } return node; } /* Sets the pointer in parent that points to child. */ #define SET_PTR_TO_CHILD(PARENT, CHILD, PREV_VAL, NEXT_VAL) do { \ if (CHILD == PARENT->prev) \ PARENT->prev = PREV_VAL; \ else { \ DO_IF_DEBUG( \ if (CHILD != PARENT->next) \ rb_fatal (PARENT, "Got invalid parent to %p " \ "(stack probably wrong).\n", CHILD); \ ); \ PARENT->next = NEXT_VAL; \ } \ } while (0) /* node ret * / \ / \ * / \ / \ * ret c ==> a node * / \ / \ * / \ / \ * a b b c */ static inline struct rb_node_hdr *rot_right (struct rb_node_hdr *node) { /* Note that we don't need to do anything special to keep the * pointers in a, b and c intact, even if they're thread * pointers pointing back to node and ret. */ struct rb_node_hdr *ret = node->prev; if (ret->flags & RB_THREAD_NEXT) { #ifdef PIKE_DEBUG if (ret->next != node) rb_fatal (node, "Bogus next thread pointer.\n"); #endif ret->flags &= ~RB_THREAD_NEXT; node->flags |= RB_THREAD_PREV; } else { node->prev = ret->next; ret->next = node; } return ret; } /* node ret * / \ / \ * / \ / \ * a ret ==> node c * / \ / \ * / \ / \ * b c a b */ static inline struct rb_node_hdr *rot_left (struct rb_node_hdr *node) { struct rb_node_hdr *ret = node->next; if (ret->flags & RB_THREAD_PREV) { #ifdef PIKE_DEBUG if (ret->prev != node) rb_fatal (node, "Bogus prev thread pointer.\n"); #endif ret->flags &= ~RB_THREAD_PREV; node->flags |= RB_THREAD_NEXT; } else { node->next = ret->prev; ret->prev = node; } return ret; } /* Returns the root node, which might have changed. The passed stack * is freed. */ static struct rb_node_hdr *rebalance_after_add (struct rb_node_hdr *node, struct rbstack_ptr rbstack) { struct rb_node_hdr *parent, *grandparent, *uncle, *top; RBSTACK_POP (rbstack, parent); #ifdef PIKE_DEBUG if (!parent) rb_fatal (node, "No parent on stack.\n"); #endif RBSTACK_POP (rbstack, grandparent); top = grandparent ? grandparent : parent; while (parent->flags & RB_RED) { /* Since the root always is black we know there's a grandparent. */ #ifdef PIKE_DEBUG if (!grandparent) rb_fatal (parent, "No parent for red node.\n"); #endif #ifdef RB_STATS rb_add_rebalance_cnt++; #endif if (parent == grandparent->prev) { uncle = grandparent->next; if (!(grandparent->flags & RB_THREAD_NEXT) && uncle->flags & RB_RED) { /* Case 1: * grandparent(B) *grandparent(R) * / \ / \ * / \ / \ * parent(R) uncle(R) ==> parent(B) uncle(B) * / \ / \ * / \ / \ * *node(R) or *node(R) node(R) or node(R) */ parent->flags &= ~RB_RED; uncle->flags &= ~RB_RED; RBSTACK_POP (rbstack, parent); if (!parent) { /* The grandparent is root - leave it black. */ top = grandparent; break; } grandparent->flags |= RB_RED; node = grandparent; RBSTACK_POP (rbstack, grandparent); top = grandparent ? grandparent : parent; } else { if (node == parent->next) { /* Case 2: * grandparent(B) grandparent(B) * / \ / \ * / \ / \ * parent(R) uncle(B) ==> node(R) uncle(B) * \ / \ * \ / \ * *node(R) *parent(R) (B) */ node = parent; parent = grandparent->prev = rot_left (node); } /* Case 3: * grandparent(B) parent(B) * / \ / \ * / \ / \ * parent(R) uncle(B) ==> node(R) grandparent(R) * / \ / \ * / \ / \ * *node(R) (B) (B) uncle(B) * * => Done. */ rot_right (grandparent); grandparent->flags |= RB_RED; parent->flags &= ~RB_RED; RBSTACK_POP (rbstack, top); if (top) SET_PTR_TO_CHILD (top, grandparent, parent, parent); else top = parent; break; } } else { #ifdef PIKE_DEBUG if (parent != grandparent->next) rb_fatal (grandparent, "Childs parent doesn't know about it (stack probably wrong).\n"); #endif /* The mirrored version of the above. */ uncle = grandparent->prev; if (!(grandparent->flags & RB_THREAD_PREV) && uncle->flags & RB_RED) { /* Case 1 */ parent->flags &= ~RB_RED; uncle->flags &= ~RB_RED; RBSTACK_POP (rbstack, parent); if (!parent) { top = grandparent; break; } grandparent->flags |= RB_RED; node = grandparent; RBSTACK_POP (rbstack, grandparent); top = grandparent ? grandparent : parent; } else { if (node == parent->prev) { /* Case 2 */ node = parent; parent = grandparent->next = rot_right (node); } /* Case 3 */ rot_left (grandparent); grandparent->flags |= RB_RED; parent->flags &= ~RB_RED; RBSTACK_POP (rbstack, top); if (top) SET_PTR_TO_CHILD (top, grandparent, parent, parent); else top = parent; break; } } } RBSTACK_FREE_SET_ROOT (rbstack, top); #ifdef PIKE_DEBUG if (top->flags & RB_RED) rb_fatal (top, "Root node not black.\n"); #endif return top; } /* Returns the root node, which might have changed. The rbstack * pointed to by rbstack_ptr goes down to the parent of the node that * was unlinked. node is the value of the pointer in the parent that * used to point to the unlinked node. * * *rbstack_ptr is freed if keep_rbstack is zero, otherwise it's set * to the new stack down to the parent node. */ static struct rb_node_hdr *rebalance_after_delete (struct rb_node_hdr *node, struct rbstack_ptr *rbstack_ptr, int keep_rbstack) { struct rb_node_hdr *parent, *sibling, *top = node; struct rbstack_ptr rbstack = *rbstack_ptr, rbstack_top; if (keep_rbstack) { rbstack_top = rbstack; RBSTACK_UP (rbstack, parent); } else RBSTACK_POP (rbstack, parent); if (!parent) { if (!node) return NULL; node->flags &= ~RB_RED; } else do { top = parent; #ifdef RB_STATS rb_add_rebalance_cnt++; #endif if (node == parent->prev) { if (!(parent->flags & RB_THREAD_PREV) && node->flags & RB_RED) { node->flags &= ~RB_RED; break; } #ifdef PIKE_DEBUG if (parent->flags & RB_THREAD_NEXT) /* Since the node in the prev subtree is the "concatenation" * of two black nodes, there must be at least two black nodes * in the next subtree too, i.e. at least one non-null * child. */ rb_fatal (parent, "Sibling in next is null; tree was unbalanced.\n"); #endif sibling = parent->next; if (sibling->flags & RB_RED) { /* Case 1: * parent(B) sibling(B) * / \ / \ * / \ / \ * *node(2B) sibling(R) ==> parent(R) (B) * / \ / \ * / \ / \ * (B) (B) *node(2B) (B) */ parent->flags |= RB_RED; sibling->flags &= ~RB_RED; rot_left (parent); top = RBSTACK_PEEK (rbstack); if (top) SET_PTR_TO_CHILD (top, parent, sibling, sibling); else top = sibling; if (keep_rbstack) rbstack_insert (&rbstack_top, &rbstack, sibling); else RBSTACK_PUSH (rbstack, sibling); #ifdef PIKE_DEBUG if (parent->flags & RB_THREAD_NEXT) rb_fatal (parent, "Sibling in next is null; tree was unbalanced.\n"); #endif sibling = parent->next; goto prev_node_red_parent; } else if (!(parent->flags & RB_RED)) { if ((sibling->flags & RB_THREAD_PREV || !(sibling->prev->flags & RB_RED)) && (sibling->flags & RB_THREAD_NEXT || !(sibling->next->flags & RB_RED))) { /* Case 2a: * parent(B) *parent(2B) * / \ / \ * / \ / \ * *node(2B) sibling(B) ==> node(B) sibling(R) * / \ / \ * / \ / \ * (B) (B) (B) (B) */ sibling->flags |= RB_RED; node = parent; if (keep_rbstack) RBSTACK_UP (rbstack, parent); else RBSTACK_POP (rbstack, parent); continue; } } else { prev_node_red_parent: if ((sibling->flags & RB_THREAD_PREV || !(sibling->prev->flags & RB_RED)) && (sibling->flags & RB_THREAD_NEXT || !(sibling->next->flags & RB_RED))) { /* Case 2b: * parent(R) parent(B) * / \ / \ * / \ / \ * *node(2B) sibling(B) ==> node(B) sibling(R) * / \ / \ * / \ / \ * (B) (B) (B) (B) * => Done. */ parent->flags &= ~RB_RED; sibling->flags |= RB_RED; break; } } if (sibling->flags & RB_THREAD_NEXT || !(sibling->next->flags & RB_RED)) { /* Case 3: * parent(?) parent(?) * / \ / \ * / \ / \ * *node(2B) sibling(B) *node(2B) new sibling(B) * / \ / \ * / \ ==> / \ * new sibling(R) (B) (B) sibling(R) * / \ / \ * / \ / \ * (B) (B) (B) (B) */ sibling->flags |= RB_RED; sibling = parent->next = rot_right (sibling); sibling->flags &= ~RB_RED; } /* Case 4: * parent(?) sibling(?) * / \ / \ * / \ / \ * *node(2B) sibling(B) ==> parent(B) (B) * / \ / \ * / \ / \ * (?) (R) node(B) (?) * => Done. */ assert (!(sibling->flags & RB_RED)); rot_left (parent); if (keep_rbstack) top = RBSTACK_PEEK (rbstack); else RBSTACK_POP (rbstack, top); if (top) { SET_PTR_TO_CHILD (top, parent, sibling, sibling); if (parent->flags & RB_RED) { sibling->flags |= RB_RED; parent->flags &= ~RB_RED; } } else { top = sibling; /* parent was the root, which always is black. */ assert (!(parent->flags & RB_RED)); } sibling->next->flags &= ~RB_RED; if (keep_rbstack) { /* Keep rbstack above the inserted element, so that we don't * need to use RBSTACK_UP. */ struct rbstack_ptr tmp = rbstack; rbstack_insert (&rbstack_top, &tmp, sibling); } break; } else { #ifdef PIKE_DEBUG if (node != parent->next) rb_fatal (parent, "Childs parent doesn't know about it (stack probably wrong).\n"); #endif /* The mirrored version of the above. */ if (!(parent->flags & RB_THREAD_NEXT) && node->flags & RB_RED) { node->flags &= ~RB_RED; break; } #ifdef PIKE_DEBUG if (parent->flags & RB_THREAD_PREV) rb_fatal (parent, "Sibling in prev is null; tree was unbalanced.\n"); #endif sibling = parent->prev; if (sibling->flags & RB_RED) { /* Case 1 */ parent->flags |= RB_RED; sibling->flags &= ~RB_RED; rot_right (parent); top = RBSTACK_PEEK (rbstack); if (top) SET_PTR_TO_CHILD (top, parent, sibling, sibling); else top = sibling; if (keep_rbstack) rbstack_insert (&rbstack_top, &rbstack, sibling); else RBSTACK_PUSH (rbstack, sibling); #ifdef PIKE_DEBUG if (parent->flags & RB_THREAD_PREV) rb_fatal (parent, "Sibling in prev is null; tree was unbalanced.\n"); #endif sibling = parent->prev; goto next_node_red_parent; } else if (!(parent->flags & RB_RED)) { if ((sibling->flags & RB_THREAD_PREV || !(sibling->prev->flags & RB_RED)) && (sibling->flags & RB_THREAD_NEXT || !(sibling->next->flags & RB_RED))) { /* Case 2a */ sibling->flags |= RB_RED; node = parent; if (keep_rbstack) RBSTACK_UP (rbstack, parent); else RBSTACK_POP (rbstack, parent); continue; } } else { next_node_red_parent: if ((sibling->flags & RB_THREAD_PREV || !(sibling->prev->flags & RB_RED)) && (sibling->flags & RB_THREAD_NEXT || !(sibling->next->flags & RB_RED))) { /* Case 2b */ parent->flags &= ~RB_RED; sibling->flags |= RB_RED; break; } } if (sibling->flags & RB_THREAD_PREV || !(sibling->prev->flags & RB_RED)) { /* Case 3 */ sibling->flags |= RB_RED; sibling = parent->prev = rot_left (sibling); sibling->flags &= ~RB_RED; } /* Case 4 */ assert (!(sibling->flags & RB_RED)); rot_right (parent); if (keep_rbstack) top = RBSTACK_PEEK (rbstack); else RBSTACK_POP (rbstack, top); if (top) { SET_PTR_TO_CHILD (top, parent, sibling, sibling); if (parent->flags & RB_RED) { sibling->flags |= RB_RED; parent->flags &= ~RB_RED; } } else { top = sibling; assert (!(parent->flags & RB_RED)); } sibling->prev->flags &= ~RB_RED; if (keep_rbstack) { struct rbstack_ptr tmp = rbstack; rbstack_insert (&rbstack_top, &tmp, sibling); } break; } } while (parent); if (keep_rbstack) { RBSTACK_UP_TO_ROOT (rbstack, top); *rbstack_ptr = rbstack_top; } else { RBSTACK_FREE_SET_ROOT (rbstack, top); *rbstack_ptr = rbstack; } #ifdef PIKE_DEBUG if (top->flags & RB_RED) rb_fatal (top, "Root node not black.\n"); #endif return top; } void low_rb_init_root (struct rb_node_hdr *node) { #ifdef PIKE_DEBUG if (!node) Pike_fatal ("New node is null.\n"); #endif #ifdef RB_STATS rb_num_adds++; #endif node->flags = (node->flags & ~RB_RED) | RB_THREAD_PREV | RB_THREAD_NEXT; node->prev = node->next = NULL; } /* The passed stack is freed. */ void low_rb_link_at_prev (struct rb_node_hdr **root, struct rbstack_ptr rbstack, struct rb_node_hdr *new) { struct rb_node_hdr *parent = RBSTACK_PEEK (rbstack); #ifdef PIKE_DEBUG if (!new) Pike_fatal ("New node is null.\n"); if (!parent) Pike_fatal ("Cannot link in root node.\n"); if (!(parent->flags & RB_THREAD_PREV)) Pike_fatal ("Cannot link in node at interior prev link.\n"); #endif #ifdef RB_STATS rb_num_adds++; #endif new->flags |= RB_RED | RB_THREAD_PREV | RB_THREAD_NEXT; new->prev = parent->prev; new->next = parent; parent->flags &= ~RB_THREAD_PREV; parent->prev = new; *root = rebalance_after_add (new, rbstack); } /* The passed stack is freed. */ void low_rb_link_at_next (struct rb_node_hdr **root, struct rbstack_ptr rbstack, struct rb_node_hdr *new) { struct rb_node_hdr *parent = RBSTACK_PEEK (rbstack); #ifdef PIKE_DEBUG if (!new) Pike_fatal ("New node is null.\n"); if (!parent) Pike_fatal ("Cannot link in root node.\n"); if (!(parent->flags & RB_THREAD_NEXT)) Pike_fatal ("Cannot link in node at interior next link.\n"); #endif #ifdef RB_STATS rb_num_adds++; #endif new->flags |= RB_RED | RB_THREAD_PREV | RB_THREAD_NEXT; new->prev = parent; new->next = parent->next; parent->flags &= ~RB_THREAD_NEXT; parent->next = new; *root = rebalance_after_add (new, rbstack); } #define DO_SIMPLE_UNLINK(UNLINK, PARENT, NODE) do { \ PARENT = RBSTACK_PEEK (rbstack); \ \ if (UNLINK->flags & RB_THREAD_PREV) { \ if (UNLINK->flags & RB_THREAD_NEXT) { \ if (PARENT) \ SET_PTR_TO_CHILD ( \ PARENT, UNLINK, \ (PARENT->flags |= RB_THREAD_PREV, NODE = UNLINK->prev), \ (PARENT->flags |= RB_THREAD_NEXT, NODE = UNLINK->next)); \ else \ NODE = NULL; \ goto simple_unlink_done; \ } \ \ else { /* prev is null. */ \ NODE = UNLINK->next; \ DO_IF_DEBUG ( \ /* Since UNLINK->prev is null, UNLINK->next must be red */ \ /* and can't have children, or else the tree is */ \ /* unbalanced. */ \ if (!(NODE->flags & RB_THREAD_PREV)) \ rb_fatal (PARENT, "Expected thread prev pointer in %p; " \ "tree is unbalanced.\n", NODE); \ ); \ NODE->prev = UNLINK->prev; \ } \ } \ \ else { /* next is null. */ \ NODE = UNLINK->prev; \ DO_IF_DEBUG ( \ if (!(NODE->flags & RB_THREAD_NEXT)) \ rb_fatal (PARENT, "Expected thread next pointer in %p; " \ "tree is unbalanced.\n", NODE); \ ); \ NODE->next = UNLINK->next; \ } \ \ if (PARENT) SET_PTR_TO_CHILD (PARENT, UNLINK, NODE, NODE); \ simple_unlink_done:; \ } while (0) #define ADJUST_STACK_TO_NEXT(RBSTACK, NEXT) do { \ struct rb_node_hdr *node = RBSTACK_PEEK (RBSTACK); \ if (NEXT && (!node || \ (!(node->flags & RB_THREAD_PREV) && node->prev == NEXT) || \ (!(node->flags & RB_THREAD_NEXT) && node->next == NEXT))) { \ RBSTACK_PUSH (RBSTACK, NEXT); \ while (!(NEXT->flags & RB_THREAD_PREV)) \ RBSTACK_PUSH (RBSTACK, NEXT = NEXT->prev); \ } \ else \ while (node != NEXT) { \ RBSTACK_POP (RBSTACK, node); \ assert (!NEXT || node != NULL); \ node = RBSTACK_PEEK (RBSTACK); \ } \ } while (0) /* The node to unlink is the one on top of the stack pointed to by * rbstack_ptr. If that node can't be unlinked (i.e. it got two * children), another node that can is found and its contents is * copied to the first one. Returns the node that actually got * unlinked. * * *rbstack_ptr is freed if keep_rbstack is zero, otherwise it's set * to the new stack down to the next node from the one that was * removed. * * See rb_remove_with_move about node_size. */ struct rb_node_hdr *low_rb_unlink_with_move (struct rb_node_hdr **root, struct rbstack_ptr *rbstack_ptr, int keep_rbstack, size_t node_size) { struct rb_node_hdr *node, *parent, *unlink, *next; struct rbstack_ptr rbstack = *rbstack_ptr; RBSTACK_POP (rbstack, node); #ifdef PIKE_DEBUG if (!node) Pike_fatal ("No node to delete on stack.\n"); #endif #ifdef RB_STATS rb_num_deletes++; #endif if (node->flags & (RB_THREAD_PREV|RB_THREAD_NEXT)) { next = node->next; unlink = node; DO_SIMPLE_UNLINK (unlink, parent, node); } else { /* Node has two subtrees, so we can't delete it. Find another one * to replace its data with. */ next = parent = node; RBSTACK_PUSH (rbstack, node); for (unlink = node->next; !(unlink->flags & RB_THREAD_PREV); unlink = unlink->prev) { parent = unlink; RBSTACK_PUSH (rbstack, unlink); } keep_flags (node, MEMCPY ((char *) node + OFFSETOF (rb_node_hdr, flags), (char *) unlink + OFFSETOF (rb_node_hdr, flags), node_size - OFFSETOF (rb_node_hdr, flags))); if (parent == node) { node = unlink->next; if (unlink->flags & RB_THREAD_NEXT) parent->flags |= RB_THREAD_NEXT; else { #ifdef PIKE_DEBUG if (!(node->flags & RB_THREAD_PREV)) rb_fatal (parent, "Expected thread prev pointer in %p; " "tree is unbalanced.\n", node); #endif node->prev = unlink->prev; } parent->next = node; } else if (unlink->flags & RB_THREAD_NEXT) { parent->flags |= RB_THREAD_PREV; parent->prev = node = unlink->prev; } else { node = unlink->next; #ifdef PIKE_DEBUG if (!(node->flags & RB_THREAD_PREV)) rb_fatal (parent, "Expected thread prev pointer in %p; " "tree is unbalanced.\n", node); #endif node->prev = unlink->prev; parent->prev = node; } } if (unlink->flags & RB_RED) { if (!keep_rbstack) RBSTACK_FREE (rbstack); } else *root = rebalance_after_delete (node, &rbstack, keep_rbstack); if (keep_rbstack) ADJUST_STACK_TO_NEXT (rbstack, next); *rbstack_ptr = rbstack; return unlink; } #if 0 struct rb_node_hdr *low_rb_unlink_with_move (struct rb_node_hdr **root, struct rbstack_ptr *rbstack_ptr, int keep_rbstack, size_t node_size) { struct rb_node_hdr *node = RBSTACK_PEEK (*rbstack_ptr), *next = rb_next (node); struct rb_node_hdr *unlink = real_low_rb_unlink_with_move (root, rbstack_ptr, 1, node_size); debug_check_rbstack (*root, *rbstack_ptr); if (node != unlink) next = node; if (RBSTACK_PEEK (*rbstack_ptr) != next) Pike_fatal ("Stack got %p on top, but next node is %p.\n", RBSTACK_PEEK (*rbstack_ptr), next); if (!keep_rbstack) RBSTACK_FREE (*rbstack_ptr); return unlink; } #endif /* Like low_rb_unlink_with_move, but relinks the nodes instead of * moving over the data. Somewhat slower unless the size of the nodes * is large. */ void low_rb_unlink_without_move (struct rb_node_hdr **root, struct rbstack_ptr *rbstack_ptr, int keep_rbstack) { struct rb_node_hdr *node, *parent, *unlink, *next; struct rbstack_ptr rbstack = *rbstack_ptr; int unlink_flags; RBSTACK_POP (rbstack, node); #ifdef PIKE_DEBUG if (!node) Pike_fatal ("No node to delete on stack.\n"); #endif #ifdef RB_STATS rb_num_deletes++; #endif if (node->flags & (RB_THREAD_PREV|RB_THREAD_NEXT)) { next = node->next; unlink = node; DO_SIMPLE_UNLINK (unlink, parent, node); unlink_flags = unlink->flags; } else { /* Node has two subtrees, so we can't delete it. Find another one * to switch places with. */ struct rb_node_hdr *orig_parent = RBSTACK_PEEK (rbstack), *tmp; struct rbstack_ptr pos; parent = unlink = node; RBSTACK_PUSH (rbstack, NULL); pos = rbstack; for (node = node->next; !(node->flags & RB_THREAD_PREV); node = node->prev) { parent = node; RBSTACK_PUSH (rbstack, node); } RBSTACK_POKE (pos, next = node); unlink_flags = node->flags; if (orig_parent) SET_PTR_TO_CHILD (orig_parent, unlink, node, node); else *root = node; for (tmp = unlink->prev; !(tmp->flags & RB_THREAD_NEXT); tmp = tmp->next) {} tmp->next = node; node->prev = unlink->prev; if (parent == unlink) { /* node replaces its parent. */ node->flags = /* Keep the thread next flag. */ (node->flags & ~(RB_FLAG_MASK & ~RB_THREAD_NEXT)) | (unlink->flags & (RB_FLAG_MASK & ~RB_THREAD_NEXT)); parent = node; node = parent->next; } else { if (node->flags & RB_THREAD_NEXT) { parent->flags |= RB_THREAD_PREV; parent->prev = node; } else parent->prev = node->next; node->flags = (node->flags & ~RB_FLAG_MASK) | (unlink->flags & RB_FLAG_MASK); node->next = unlink->next; node = parent->prev; } } if (unlink_flags & RB_RED) { if (!keep_rbstack) RBSTACK_FREE (rbstack); } else *root = rebalance_after_delete (node, &rbstack, keep_rbstack); if (keep_rbstack) ADJUST_STACK_TO_NEXT (rbstack, next); *rbstack_ptr = rbstack; } #if 0 void low_rb_unlink_without_move (struct rb_node_hdr **root, struct rbstack_ptr *rbstack_ptr, int keep_rbstack) { struct rb_node_hdr *node = RBSTACK_PEEK (*rbstack_ptr), *next = rb_next (node); real_low_rb_unlink_without_move (root, rbstack_ptr, 1); debug_check_rbstack (*root, *rbstack_ptr); if (RBSTACK_PEEK (*rbstack_ptr) != next) Pike_fatal ("Stack got %p on top, but next node is %p.\n", RBSTACK_PEEK (*rbstack_ptr), next); if (!keep_rbstack) RBSTACK_FREE (*rbstack_ptr); } #endif #ifdef ENABLE_UNUSED_RB_FUNCTIONS /* These functions are disabled since they aren't used from anywhere. * If you like to use them, just let me know (they are tested). /mast */ /* Does not replace an existing equal node. Returns the node in the * tree. It might not be the passed new node if an equal one was * found. */ struct rb_node_hdr *rb_insert (struct rb_node_hdr **root, rb_find_fn *find_fn, void *key, struct rb_node_hdr *new) { if (*root) { struct rb_node_hdr *node = *root; RBSTACK_INIT (rbstack); LOW_RB_TRACK ( rbstack, node, cmp_res = find_fn (key, node), { /* Got less. */ low_rb_link_at_next (root, rbstack, new); }, { /* Got equal - new not used. */ RBSTACK_FREE (rbstack); return node; }, { /* Got greater. */ low_rb_link_at_prev (root, rbstack, new); }); } else { low_rb_init_root (new); *root = new; } return new; } void rb_add (struct rb_node_hdr **root, rb_find_fn *find_fn, void *key, struct rb_node_hdr *new) { if (*root) { struct rb_node_hdr *node = *root; RBSTACK_INIT (rbstack); LOW_RB_TRACK_NEQ ( rbstack, node, cmp_res = find_fn (key, node) >= 0 ? 1 : -1, low_rb_link_at_next (root, rbstack, new), /* Got less or equal. */ low_rb_link_at_prev (root, rbstack, new) /* Got greater. */ ); } else { low_rb_init_root (new); *root = new; } } void rb_add_after (struct rb_node_hdr **root, rb_find_fn *find_fn, void *key, struct rb_node_hdr *new, struct rb_node_hdr *existing) { if (*root) { struct rb_node_hdr *node = *root; RBSTACK_INIT (rbstack); if (existing) { LOW_RB_TRACK_NEQ ( rbstack, node, cmp_res = find_fn (key, node) >= 0 ? 1 : -1, ;, ;); while (node != existing) { LOW_RB_TRACK_PREV (rbstack, node); #ifdef PIKE_DEBUG if (!node) Pike_fatal ("Tree doesn't contain the existing node.\n"); #endif } if (node->flags & RB_THREAD_NEXT) { low_rb_link_at_next (root, rbstack, new); return; } else node = node->next; } /* Link at lowest position. */ RBSTACK_PUSH (rbstack, node); while (!(node->flags & RB_THREAD_PREV)) { node = node->prev; RBSTACK_PUSH (rbstack, node); } low_rb_link_at_prev (root, rbstack, new); } else { #ifdef PIKE_DEBUG if (existing) Pike_fatal ("Tree doesn't contain the existing node.\n"); #endif low_rb_init_root (new); *root = new; } } /* Returns the node to free, if any. Note that rb_remove_with_move * is usually faster if the node size is small. */ struct rb_node_hdr *rb_remove (struct rb_node_hdr **root, rb_find_fn *find_fn, void *key) { struct rb_node_hdr *node = *root; if (node) { RBSTACK_INIT (rbstack); LOW_RB_TRACK ( rbstack, node, cmp_res = find_fn (key, node), { /* Got less. */ }, { /* Got equal. */ low_rb_unlink_without_move (root, rbstack); return node; }, { /* Got greater. */ }); RBSTACK_FREE (rbstack); } return NULL; } void rb_remove_node (struct rb_node_hdr **root, rb_find_fn *find_fn, void *key, struct rb_node_hdr *to_delete) { struct rb_node_hdr *node = *root; RBSTACK_INIT (rbstack); #ifdef PIKE_DEBUG if (!node) Pike_fatal ("Tree is empty.\n"); #if 0 if (find_fn (key, to_delete)) Pike_fatal ("Given key doesn't match the node to delete.\n"); #endif #endif LOW_RB_TRACK_NEQ (rbstack, node, cmp_res = find_fn (key, node) >= 0 ? 1 : -1, ;, ;); while (node != to_delete) { LOW_RB_TRACK_PREV (rbstack, node); #ifdef PIKE_DEBUG if (!node) Pike_fatal ("Tree doesn't contain the node to delete.\n"); #endif } low_rb_unlink_without_move (root, rbstack); } /* Variant of rb_remove that moves the contents of another node to the * one to be removed if it can't be unlinked. node_size is the size of * the whole node, including rb_node_hdr. If cleanup_fn isn't NULL, * it's called for the node whose contents is removed, while the node * being returned is the one to actually free. */ struct rb_node_hdr *rb_remove_with_move (struct rb_node_hdr **root, rb_find_fn *find_fn, void *key, size_t node_size, rb_free_fn *cleanup_fn, void *cleanup_fn_extra) { struct rb_node_hdr *node = *root; if (node) { RBSTACK_INIT (rbstack); LOW_RB_TRACK ( rbstack, node, cmp_res = find_fn (key, node), { /* Got less. */ }, { /* Got equal. */ if (cleanup_fn) cleanup_fn (node, cleanup_fn_extra); return low_rb_unlink_with_move (root, rbstack, node_size); }, { /* Got greater. */ }); RBSTACK_FREE (rbstack); } return NULL; } /* Returns the node to actually free. See rb_remove about * node_size. */ struct rb_node_hdr *rb_remove_node_with_move (struct rb_node_hdr **root, rb_find_fn *find_fn, void *key, struct rb_node_hdr *to_delete, size_t node_size) { struct rb_node_hdr *node = *root; RBSTACK_INIT (rbstack); #ifdef PIKE_DEBUG if (!node) Pike_fatal ("Tree is empty.\n"); #if 0 if (find_fn (key, to_delete)) Pike_fatal ("Given key doesn't match the node to delete.\n"); #endif #endif LOW_RB_TRACK_NEQ (rbstack, node, cmp_res = find_fn (key, node) >= 0 ? 1 : -1, ;, ;); while (node != to_delete) { LOW_RB_TRACK_PREV (rbstack, node); #ifdef PIKE_DEBUG if (!node) Pike_fatal ("Tree doesn't contain the node to delete.\n"); #endif } return low_rb_unlink_with_move (root, rbstack, node_size); } struct rb_node_hdr *rb_find_eq (struct rb_node_hdr *root, rb_find_fn *find_fn, void *key) { if (root) LOW_RB_FIND (root, cmp_res = find_fn (key, root), ;, return root, ;); return NULL; } struct rb_node_hdr *rb_find_lt (struct rb_node_hdr *root, rb_find_fn *find_fn, void *key) { if (root) LOW_RB_FIND_NEQ (root, cmp_res = find_fn (key, root) <= 0 ? -1 : 1, return root, return root->prev); return NULL; } struct rb_node_hdr *rb_find_gt (struct rb_node_hdr *root, rb_find_fn *find_fn, void *key) { if (root) LOW_RB_FIND_NEQ (root, cmp_res = find_fn (key, root) >= 0 ? 1 : -1, return root->next, return root); return NULL; } struct rb_node_hdr *rb_find_le (struct rb_node_hdr *root, rb_find_fn *find_fn, void *key) { if (root) LOW_RB_FIND_NEQ (root, cmp_res = find_fn (key, root) >= 0 ? 1 : -1, return root, return root->prev); return NULL; } struct rb_node_hdr *rb_find_ge (struct rb_node_hdr *root, rb_find_fn *find_fn, void *key) { if (root) LOW_RB_FIND_NEQ (root, cmp_res = find_fn (key, root) <= 0 ? -1 : 1, return root->next, return root); return NULL; } #endif /* ENABLE_UNUSED_RB_FUNCTIONS */ struct rb_node_hdr *rb_get_nth (struct rb_node_hdr *root, size_t n) { #ifdef PIKE_DEBUG size_t index = n; #endif if ((root = rb_first (root))) { while (n) { n--; root = rb_next (root); #ifdef PIKE_DEBUG if (!root) goto tree_too_small; #endif } return root; } #ifdef PIKE_DEBUG tree_too_small: Pike_fatal ("Tree too small for index %"PRINTSIZET"u.\n", index); #endif return (struct rb_node_hdr *) (ptrdiff_t) -1; } size_t rb_sizeof (struct rb_node_hdr *root) { size_t size = 0; if ((root = rb_first (root))) { do { size++; } while ((root = rb_next (root))); } return size; } #ifdef ENABLE_UNUSED_RB_FUNCTIONS void rb_free (struct rb_node_hdr *root, rb_free_fn *free_node_fn, void *extra) { if ((root = rb_first (root))) { struct rb_node_hdr *next; do { next = rb_next (root); free_node_fn (root, extra); root = next; } while (root); } } int rb_equal (struct rb_node_hdr *a, struct rb_node_hdr *b, rb_equal_fn *node_equal_fn, void *extra) { a = rb_first (a); b = rb_first (b); while (a && b) { if (!node_equal_fn (a, b, extra)) return 0; a = rb_next (a); b = rb_next (b); } return !(a || b); } struct rb_node_hdr *rb_copy (struct rb_node_hdr *source, rb_copy_fn *copy_node_fn, void *extra) { if (source) { struct rb_node_hdr *copy, *target, *new, *t_prev_tgt = NULL, *t_next_src = NULL; RBSTACK_INIT (s_stack); RBSTACK_INIT (t_stack); copy = target = copy_node_fn (source, extra); copy->flags = (copy->flags & ~RB_FLAG_MASK) | (source->flags & RB_FLAG_MASK); LOW_RB_TRAVERSE ( 1, s_stack, source, { /* Push. */ }, { /* prev is leaf. */ target->prev = t_prev_tgt; }, { /* prev is subtree. */ new = target->prev = copy_node_fn (source->prev, extra); new->flags = (new->flags & ~RB_FLAG_MASK) | (source->prev->flags & RB_FLAG_MASK); RBSTACK_PUSH (t_stack, target); target = new; }, { /* Between. */ t_prev_tgt = target; if (t_next_src) { t_next_src->next = target; t_next_src = NULL; } }, { /* next is leaf. */ t_next_src = target; }, { /* next is subtree. */ new = target->next = copy_node_fn (source->next, extra); new->flags = (new->flags & ~RB_FLAG_MASK) | (source->next->flags & RB_FLAG_MASK); RBSTACK_PUSH (t_stack, target); target = new; }, { /* Pop. */ RBSTACK_POP (t_stack, target); }); if (t_next_src) t_next_src->next = NULL; return copy; } else return NULL; } #endif /* ENABLE_UNUSED_RB_FUNCTIONS */ /* Converts a tree to an ordered list of nodes linked by the next * pointers. */ struct rb_node_hdr *rb_make_list (struct rb_node_hdr *tree) { struct rb_node_hdr *list = tree = rb_first (tree); if (tree) while ((tree = tree->next = rb_next (tree))) {} return list; } /* Converts a list of nodes linked by the next pointers to a perfectly * balanced tree (with a minimum of black nodes). Time complexity is * O(length). Returns the tree root. */ struct rb_node_hdr *rb_make_tree (struct rb_node_hdr *list, size_t length) { struct rb_node_hdr *root = NULL; if (length > 1) { unsigned depth, *top_idx; size_t deep_end, count = 0, start = 0, idx = 1; struct rb_node_hdr **stack, *prev_tgt = NULL, *next_src = NULL; int stack_malloced = 0; { unsigned l = 0, h = sizeof (length) * CHAR_BIT; do { depth = (l + h) >> 1; if (1u << depth <= length) l = depth + 1; else h = depth; } while (l < h); if (1u << depth <= length) depth++; } deep_end = (length - (1 << (depth - 1))) << 1; if (!(length & 1)) deep_end |= 1; { size_t stack_size = depth * sizeof (struct rb_node_hdr *) + (depth + 1) * sizeof (unsigned); #ifdef HAVE_ALLOCA stack = alloca (stack_size); if (!stack) #endif { stack = xalloc (stack_size); stack_malloced = 1; } top_idx = (unsigned *) stack + depth; memset (top_idx, 0, (depth + 1) * sizeof (unsigned)); depth--; } while (count < length) { struct rb_node_hdr *next; #ifdef PIKE_DEBUG if (!list) Pike_fatal ("Premature end of list at %"PRINTSIZET"u, " "expected %"PRINTSIZET"u.\n", count, length); #endif next = list->next; if (idx > start) { /* Leaf node. */ idx = start; list->flags |= RB_THREAD_PREV|RB_THREAD_NEXT; next_src = stack[idx] = list; list->prev = prev_tgt; } else { /* Interior node. */ idx = top_idx[idx]; list->flags &= ~(RB_THREAD_PREV|RB_THREAD_NEXT); prev_tgt = next_src->next = stack[idx] = list; list->prev = stack[idx - 1]; if (idx == depth) { assert (!root); root = list; } } if (count++ == deep_end) { if (idx) { /* Interior node is "half a leaf". */ next_src = list; list->flags |= RB_THREAD_NEXT; } start = 1; } if (idx & 1) list->flags &= ~RB_RED; else list->flags |= RB_RED; if (top_idx[idx] == top_idx[idx + 1]) top_idx[idx] = idx + 1; else { top_idx[idx] = top_idx[idx + 1]; stack[idx + 1]->next = list; } list = next; } next_src->next = NULL; root->flags &= ~RB_RED; if (stack_malloced) xfree (stack); } else if (length) { root = list; #ifdef PIKE_DEBUG list = list->next; #endif low_rb_init_root (root); } #ifdef PIKE_DEBUG if (list) Pike_fatal ("List longer than expected %d.\n", length); #endif return root; } #ifdef ENABLE_UNUSED_RB_FUNCTIONS struct linear_merge_cleanup { int operation; struct rb_node_hdr *a, *b, *res; rb_merge_free_fn *free_node_fn; void *extra; }; static void do_linear_merge_cleanup (struct linear_merge_cleanup *s) { struct rb_node_hdr *node, *next; rb_merge_free_fn *free_node_fn = s->free_node_fn; void *extra = s->extra; for (node = s->res; node; node = next) { next = node->next; free_node_fn (node, extra, MERGE_TREE_RES); } if (s->operation & PIKE_MERGE_DESTR_A) for (node = s->a; node; node = next) { next = rb_prev (node); free_node_fn (node, extra, MERGE_TREE_A); } if (s->operation & PIKE_MERGE_DESTR_B) for (node = s->b; node; node = next) { next = rb_prev (node); free_node_fn (node, extra, MERGE_TREE_B); } } /* Merges two trees in linear time (no more, no less). The operation * argument describes the way to merge, like the one given to merge() * in array.c. Two extra bits, PIKE_MERGE_DESTR_A and * PIKE_MERGE_DESTR_B, tells whether or not to be destructive on the * two passed trees. If destructive on a tree, the remaining nodes in * it will be freed with free_node_fn, otherwise copy_node_fn will be * used to copy nodes from it to the result. The two callbacks will * receive either MERGE_TREE_A or MERGE_TREE_B as the third arg, * depending on whether the node argument comes from tree a or tree b, * respectively. free_node_fn might also get MERGE_TREE_RES to clean * up any newly created node copies in the result, in case of * exception. * * The function returns a list linked by the next pointers, and if * length is nonzero it'll write the length of the list there. The * caller can then use these as arguments to rb_make_tree. * * NB: It doesn't handle making duplicates of the same node, i.e. * PIKE_ARRAY_OP_A without PIKE_ARRAY_OP_SKIP_A. Not a problem since * none of the currently defined operations use that. * * NB: It's assumed that a and b aren't part of the same tree. */ struct rb_node_hdr *rb_linear_merge ( struct rb_node_hdr *a, struct rb_node_hdr *b, int operation, rb_cmp_fn *cmp_fn, void *cmp_fn_extra, rb_merge_copy_fn *copy_node_fn, void *copy_fn_extra, rb_merge_free_fn *free_node_fn, void *free_fn_extra, size_t *length) { struct rb_node_hdr *n; size_t len = 0; int cmp_res, op; struct linear_merge_cleanup s; ONERROR uwp; s.operation = operation; s.free_node_fn = free_node_fn; s.extra = free_fn_extra; SET_ONERROR (uwp, do_linear_merge_cleanup, &s); LOW_RB_MERGE ( x, s.a, s.b, s.res, len, operation, ;, ;, { cmp_res = cmp_fn (s.a, s.b, cmp_fn_extra); }, { /* Copy a. */ new_node = operation & PIKE_MERGE_DESTR_A ? s.a : copy_node_fn (s.a, copy_fn_extra, MERGE_TREE_A); }, { /* Free a. */ if (operation & PIKE_MERGE_DESTR_A) free_node_fn (s.a, free_fn_extra, MERGE_TREE_A); }, { /* Copy b. */ new_node = operation & PIKE_MERGE_DESTR_B ? s.b : copy_node_fn (s.b, copy_fn_extra, MERGE_TREE_B); }, { /* Free b. */ if (operation & PIKE_MERGE_DESTR_B) free_node_fn (s.b, free_fn_extra, MERGE_TREE_B); }); UNSET_ONERROR (uwp); if (length) *length = len; return s.res; } #endif /* ENABLE_UNUSED_RB_FUNCTIONS */ #ifdef RB_STATS size_t rb_num_finds = 0, rb_find_depth = 0; size_t rb_num_sidesteps = 0, rb_num_sidestep_ops = 0; size_t rb_num_tracks = 0, rb_track_depth = 0; size_t rb_num_sidetracks = 0, rb_num_sidetrack_ops = 0; size_t rb_max_depth = 0; size_t rb_num_traverses = 0, rb_num_traverse_ops = 0; size_t rbstack_slice_allocs = 0; size_t rb_num_adds = 0, rb_add_rebalance_cnt = 0; size_t rb_num_deletes = 0, rb_del_rebalance_cnt = 0; void reset_rb_stats() { rb_num_sidesteps = rb_num_sidestep_ops = 0; rb_num_finds = rb_find_depth = 0; rb_num_tracks = rb_track_depth = 0; rb_num_sidetracks = rb_num_sidetrack_ops = 0; rb_max_depth = 0; rb_num_traverses = rb_num_traverse_ops = 0; rbstack_slice_allocs = 0; rb_num_adds = rb_add_rebalance_cnt = 0; rb_num_deletes = rb_del_rebalance_cnt = 0; } void print_rb_stats (int reset) { fprintf (stderr, "rbtree stats:\n" " number of finds . . . . . . %10"PRINTSIZET"u\n" " avg find depth . . . . . . . %10.2f\n" " number of sidesteps . . . . %10"PRINTSIZET"u\n" " avg ops per sidestep . . . . %10.2f\n" " number of tracks . . . . . . %10"PRINTSIZET"u\n" " avg track depth . . . . . . %10.2f\n" " number of sidetracks . . . . %10"PRINTSIZET"u\n" " avg ops per sidetrack . . . %10.2f\n" " maximum depth . . . . . . . %10"PRINTSIZET"u\n" " number of traverses . . . . %10"PRINTSIZET"u\n" " avg ops per traverse . . . . %10.2f\n" " allocated stack slices . . . %10"PRINTSIZET"u\n" " number of adds . . . . . . . %10"PRINTSIZET"u\n" " avg add rebalance count . . %10.2f\n" " number of deletes . . . . . %10"PRINTSIZET"u\n" " avg delete rebalance count . %10.2f\n", rb_num_finds, (double) rb_find_depth / rb_num_finds, rb_num_sidesteps, (double) rb_num_sidestep_ops / rb_num_sidesteps, rb_num_tracks, (double) rb_track_depth / rb_num_tracks, rb_num_sidetracks, (double) rb_num_sidetrack_ops / rb_num_sidetracks, rb_max_depth, rb_num_traverses, (double) rb_num_traverse_ops / rb_num_traverses, rbstack_slice_allocs, rb_num_adds, (double) rb_add_rebalance_cnt / rb_num_adds, rb_num_deletes, (double) rb_del_rebalance_cnt / rb_num_deletes); if (reset) reset_rb_stats(); } #endif /* RB_STATS */ #if defined (PIKE_DEBUG) || defined (TEST_MULTISET) void debug_dump_rb_tree (struct rb_node_hdr *root, dump_data_fn *dump_data, void *extra) { if (root) { struct rb_node_hdr *node = root; struct rb_node_hdr *n, *n2; struct rbstack_ptr p; size_t depth = 0; RBSTACK_INIT (rbstack); LOW_RB_TRAVERSE ( 1, rbstack, node, { /* Push. */ depth++; p = rbstack; RBSTACK_UP (p, n); while (n) { if (n == node) { fprintf (stderr, "[Circular %p]", node); goto skip_node; } RBSTACK_UP (p, n); } fputc ('(', stderr); }, { /* prev is leaf. */ p = rbstack; n2 = node; RBSTACK_UP (p, n); while (n && (n->flags & RB_THREAD_NEXT || n->next != n2)) { n2 = n; RBSTACK_UP (p, n); } if (node->prev != n) fprintf (stderr, "[Thread ptr is %p, expected %p] ", node->prev, n); }, { /* prev is subtree. */ if (!node->prev) { fputs ("[Zero subtree]", stderr); goto between_1; } }, { /* Between nodes. */ if (!(node->flags & RB_THREAD_PREV)) fprintf (stderr, "\n%*s", depth, ""); if (node == root) fputs ("root=", stderr); fprintf (stderr, "%p/%c", node, node->flags & RB_RED ? 'R' : 'B'); if (dump_data) { fputs (": ", stderr); dump_data (node, extra); } }, { /* next is leaf. */ p = rbstack; n2 = node; RBSTACK_UP (p, n); while (n && (n->flags & RB_THREAD_PREV || n->prev != n2)) { n2 = n; RBSTACK_UP (p, n); } if (node->next != n) fprintf (stderr, " [Thread ptr is %p, expected %p]", node->next, n); }, { /* next is subtree. */ if (!node->next) { fputs (" [Zero subtree]", stderr); goto leave_1; } fprintf (stderr, "\n%*s", depth, ""); }, { /* Pop. */ fputc (')', stderr); depth--; skip_node: ; }); fputc ('\n', stderr); } else fprintf (stderr, "(empty tree)\n"); } /* If pos isn't zero, it points to a pointer in the stack that will be * marked in the output. */ void debug_dump_rbstack (struct rbstack_ptr rbstack, struct rbstack_ptr *pos) { struct rb_node_hdr *node, *ptr_node = (void *) (ptrdiff_t) -1; RBSTACK_INIT (reversed); while (1) { int here = pos ? pos->ssp == rbstack.ssp && pos->slice == rbstack.slice : 0; RBSTACK_UP (rbstack, node); if (here) ptr_node = node; if (!node) break; RBSTACK_PUSH (reversed, node); } if (pos && !ptr_node) fputs ("* ", stderr); while (1) { RBSTACK_POP (reversed, node); if (!node) break; fprintf (stderr, "%p ", node); if (pos && ptr_node == node) fputs ("* ", stderr); } if (pos && ptr_node == (void *) (ptrdiff_t) -1) fputs ("(pos outside stack)", stderr); fputc ('\n', stderr); } static void debug_rb_fatal (struct rb_node_hdr *tree, const char *fmt, ...) { va_list args; va_start (args, fmt); (void) VFPRINTF (stderr, fmt, args); fputs ("Dumping tree:\n", stderr); debug_dump_rb_tree (tree, NULL, NULL); debug_fatal ("\r"); } static void debug_custom_rb_fatal (struct rb_node_hdr *tree, dump_data_fn *dump_data, void *extra, const char *fmt, ...) { va_list args; va_start (args, fmt); (void) VFPRINTF (stderr, fmt, args); fputs ("Dumping tree:\n", stderr); debug_dump_rb_tree (tree, dump_data, extra); debug_fatal ("\r"); } void debug_check_rb_tree (struct rb_node_hdr *root, dump_data_fn *dump_data, void *extra) { if (root) { struct rb_node_hdr *node = root, *n, *n2; struct rbstack_ptr p; size_t blacks = 1, max_blacks = 0, depth = 0; RBSTACK_INIT (rbstack); if (root->flags & RB_RED) custom_rb_fatal (root, dump_data, extra, "Root node not black.\n"); LOW_RB_TRAVERSE ( 1, rbstack, node, { /* Push. */ depth++; p = rbstack; RBSTACK_UP (p, n); while (n) { if (n == node) custom_rb_fatal (root, dump_data, extra, "Circular subtrees @ %p.\n", node); RBSTACK_UP (p, n); } if (!(node->flags & RB_RED)) blacks++; }, { /* prev is leaf. */ if (max_blacks) { if (blacks != max_blacks) custom_rb_fatal (root, dump_data, extra, "Unbalanced tree - leftmost branch is %d, " "prev @ %p is %d.\n", max_blacks, node, blacks); } else max_blacks = blacks; p = rbstack; n2 = node; RBSTACK_UP (p, n); while (n && (n->flags & RB_THREAD_NEXT || n->next != n2)) { n2 = n; RBSTACK_UP (p, n); } if (node->prev != n) custom_rb_fatal (root, dump_data, extra, "Thread prev pointer @ %p is %p, expected %p.\n", node, node->prev, n); }, { /* prev is subtree. */ if (!node->prev) custom_rb_fatal (root, dump_data, extra, "Subtree prev is null @ %p.\n", node); if (node->flags & RB_RED && node->prev->flags & RB_RED) custom_rb_fatal (root, dump_data, extra, "Red node got red subtree prev node @ %p.\n", node); }, { /* Between nodes. */ }, { /* next is leaf. */ if (blacks != max_blacks) custom_rb_fatal (root, dump_data, extra, "Unbalanced tree - leftmost branch is %d, " "next @ %p is %d.\n", max_blacks, node, blacks); p = rbstack; n2 = node; RBSTACK_UP (p, n); while (n && (n->flags & RB_THREAD_PREV || n->prev != n2)) { n2 = n; RBSTACK_UP (p, n); } if (node->next != n) custom_rb_fatal (root, dump_data, extra, "Thread next pointer @ %p is %p, expected %p.\n", node, node->next, n); }, { /* next is subtree. */ if (!node->next) custom_rb_fatal (root, dump_data, extra, "Subtree next is null @ %p.\n", node); if (node->flags & RB_RED && node->next->flags & RB_RED) custom_rb_fatal (root, dump_data, extra, "Red node got red subtree next node @ %p.\n", node); }, { /* Pop. */ if (!(node->flags & RB_RED)) blacks--; depth--; }); } } void debug_check_rbstack (struct rb_node_hdr *root, struct rbstack_ptr rbstack) { struct rbstack_ptr rbstack_top = rbstack; struct rb_node_hdr *snode, *tnode = root; RBSTACK_INIT (reversed); while (1) { RBSTACK_UP (rbstack, snode); if (!snode) break; RBSTACK_PUSH (reversed, snode); } RBSTACK_POP (reversed, snode); if (!snode) return; if (snode != tnode) { fputs ("rbstack: ", stderr); debug_dump_rbstack (rbstack_top, NULL); rb_fatal (root, "rbstack root %p != tree root.\n", snode); } while (1) { RBSTACK_POP (reversed, snode); if (!snode) break; if (!(tnode->flags & RB_THREAD_PREV) && snode == tnode->prev) {tnode = snode; continue;} if (!(tnode->flags & RB_THREAD_NEXT) && snode == tnode->next) {tnode = snode; continue;} rb_fatal (root, "rbstack differs from tree: Node %p got no child %p.\n", tnode, snode); } } #endif /* PIKE_DEBUG || TEST_MULTISET */

pike.git/ src/ rbtree.c > 401b710e041c53f60569bc784a3b6ea8b229a188 [Annotate]