diff options
Diffstat (limited to 'ext/rpatricia/patricia.c')
| -rw-r--r-- | ext/rpatricia/patricia.c | 1038 |
1 files changed, 1038 insertions, 0 deletions
diff --git a/ext/rpatricia/patricia.c b/ext/rpatricia/patricia.c new file mode 100644 index 0000000..d211a34 --- /dev/null +++ b/ext/rpatricia/patricia.c @@ -0,0 +1,1038 @@ +/* + * $Id: patricia.c,v 1.7 2005/12/07 20:46:41 dplonka Exp $ + * Dave Plonka <plonka@doit.wisc.edu> + * + * This product includes software developed by the University of Michigan, + * Merit Network, Inc., and their contributors. + * + * This file had been called "radix.c" in the MRT sources. + * + * I renamed it to "patricia.c" since it's not an implementation of a general + * radix trie. Also I pulled in various requirements from "prefix.c" and + * "demo.c" so that it could be used as a standalone API. + */ + +static char copyright[] = +"This product includes software developed by the University of Michigan, Merit" +"Network, Inc., and their contributors."; + +#include <assert.h> /* assert */ +#include <ctype.h> /* isdigit */ +#include <errno.h> /* errno */ +#include <math.h> /* sin */ +#include <stddef.h> /* NULL */ +#include <stdio.h> /* sprintf, fprintf, stderr */ +#include <stdlib.h> /* free, atol, calloc */ +#include <string.h> /* memcpy, strchr, strlen */ +#include <sys/types.h> /* BSD: for inet_addr */ +#include <sys/socket.h> /* BSD, Linux: for inet_addr */ +#include <netinet/in.h> /* BSD, Linux: for inet_addr */ +#include <arpa/inet.h> /* BSD, Linux, Solaris: for inet_addr */ + +#include "patricia.h" + +#define Delete free + +/* { from prefix.c */ + +/* prefix_tochar + * convert prefix information to bytes + */ +u_char * +prefix_tochar (prefix_t * prefix) +{ + if (prefix == NULL) + return (NULL); + + return ((u_char *) & prefix->add.sin); +} + +int +comp_with_mask (void *addr, void *dest, u_int mask) +{ + + if ( /* mask/8 == 0 || */ memcmp (addr, dest, mask / 8) == 0) { + int n = mask / 8; + int m = ((-1) << (8 - (mask % 8))); + + if (mask % 8 == 0 || (((u_char *)addr)[n] & m) == (((u_char *)dest)[n] & m)) + return (1); + } + return (0); +} + +/* inet_pton substitute implementation + * Uses inet_addr to convert an IP address in dotted decimal notation into + * unsigned long and copies the result to dst. + * Only supports AF_INET. Follows standard error return conventions of + * inet_pton. + */ +int +inet_pton (int af, const char *src, void *dst) +{ + u_long result; + + if (af == AF_INET) { + result = inet_addr(src); + if (result == -1) + return 0; + else { + memcpy (dst, &result, 4); + return 1; + } + } +#ifdef NT +#ifdef HAVE_IPV6 + else if (af == AF_INET6) { + struct in6_addr Address; + return (inet6_addr(src, &Address)); + } +#endif /* HAVE_IPV6 */ +#endif /* NT */ +#ifndef NT + else { + + errno = EAFNOSUPPORT; + return -1; + } +#endif /* NT */ +} + +/* this allows imcomplete prefix */ +int +my_inet_pton (int af, const char *src, void *dst) +{ + if (af == AF_INET) { + int i, c, val; + u_char xp[4] = {0, 0, 0, 0}; + + for (i = 0; ; i++) { + c = *src++; + if (!isdigit (c)) + return (-1); + val = 0; + do { + val = val * 10 + c - '0'; + if (val > 255) + return (0); + c = *src++; + } while (c && isdigit (c)); + xp[i] = val; + if (c == '\0') + break; + if (c != '.') + return (0); + if (i >= 3) + return (0); + } + memcpy (dst, xp, 4); + return (1); +#ifdef HAVE_IPV6 + } else if (af == AF_INET6) { + return (inet_pton (af, src, dst)); +#endif /* HAVE_IPV6 */ + } else { +#ifndef NT + errno = EAFNOSUPPORT; +#endif /* NT */ + return -1; + } +} + +/* + * convert prefix information to ascii string with length + * thread safe and (almost) re-entrant implementation + */ +char * +prefix_toa2x (prefix_t *prefix, char *buff, int with_len) +{ + if (prefix == NULL) + return ("(Null)"); + assert (prefix->ref_count >= 0); + if (buff == NULL) { + + struct buffer { + char buffs[16][48+5]; + u_int i; + } *buffp; + +# if 0 + THREAD_SPECIFIC_DATA (struct buffer, buffp, 1); +# else + { /* for scope only */ + static struct buffer local_buff; + buffp = &local_buff; + } +# endif + if (buffp == NULL) { + /* XXX should we report an error? */ + return (NULL); + } + + buff = buffp->buffs[buffp->i++%16]; + } + if (prefix->family == AF_INET) { + u_char *a; + assert (prefix->bitlen <= 32); + a = prefix_touchar (prefix); + if (with_len) { + sprintf (buff, "%d.%d.%d.%d/%d", a[0], a[1], a[2], a[3], + prefix->bitlen); + } + else { + sprintf (buff, "%d.%d.%d.%d", a[0], a[1], a[2], a[3]); + } + return (buff); + } +#ifdef HAVE_IPV6 + else if (prefix->family == AF_INET6) { + char *r; + r = (char *) inet_ntop (AF_INET6, &prefix->add.sin6, buff, 48 /* a guess value */ ); + if (r && with_len) { + assert (prefix->bitlen <= 128); + sprintf (buff + strlen (buff), "/%d", prefix->bitlen); + } + return (buff); + } +#endif /* HAVE_IPV6 */ + else + return (NULL); +} + +/* prefix_toa2 + * convert prefix information to ascii string + */ +char * +prefix_toa2 (prefix_t *prefix, char *buff) +{ + return (prefix_toa2x (prefix, buff, 0)); +} + +/* prefix_toa + */ +char * +prefix_toa (prefix_t * prefix) +{ + return (prefix_toa2 (prefix, (char *) NULL)); +} + +prefix_t * +New_Prefix2 (int family, void *dest, int bitlen, prefix_t *prefix) +{ + int dynamic_allocated = 0; + int default_bitlen = 32; + +#ifdef HAVE_IPV6 + if (family == AF_INET6) { + default_bitlen = 128; + if (prefix == NULL) { + prefix = calloc(1, sizeof (prefix6_t)); + dynamic_allocated++; + } + memcpy (&prefix->add.sin6, dest, 16); + } + else +#endif /* HAVE_IPV6 */ + if (family == AF_INET) { + if (prefix == NULL) { +#ifndef NT + prefix = calloc(1, sizeof (prefix4_t)); +#else + //for some reason, compiler is getting + //prefix4_t size incorrect on NT + prefix = calloc(1, sizeof (prefix_t)); +#endif /* NT */ + + dynamic_allocated++; + } + memcpy (&prefix->add.sin, dest, 4); + } + else { + return (NULL); + } + + prefix->bitlen = (bitlen >= 0)? bitlen: default_bitlen; + prefix->family = family; + prefix->ref_count = 0; + if (dynamic_allocated) { + prefix->ref_count++; + } +/* fprintf(stderr, "[C %s, %d]\n", prefix_toa (prefix), prefix->ref_count); */ + return (prefix); +} + +prefix_t * +New_Prefix (int family, void *dest, int bitlen) +{ + return (New_Prefix2 (family, dest, bitlen, NULL)); +} + +/* ascii2prefix + */ +prefix_t * +ascii2prefix (int family, char *string) +{ + u_long bitlen, maxbitlen = 0; + char *cp; + struct in_addr sin; +#ifdef HAVE_IPV6 + struct in6_addr sin6; +#endif /* HAVE_IPV6 */ + int result; + char save[MAXLINE]; + + if (string == NULL) + return (NULL); + + /* easy way to handle both families */ + if (family == 0) { + family = AF_INET; +#ifdef HAVE_IPV6 + if (strchr (string, ':')) family = AF_INET6; +#endif /* HAVE_IPV6 */ + } + + if (family == AF_INET) { + maxbitlen = 32; + } +#ifdef HAVE_IPV6 + else if (family == AF_INET6) { + maxbitlen = 128; + } +#endif /* HAVE_IPV6 */ + + if ((cp = strchr (string, '/')) != NULL) { + bitlen = atol (cp + 1); + /* *cp = '\0'; */ + /* copy the string to save. Avoid destroying the string */ + assert (cp - string < MAXLINE); + memcpy (save, string, cp - string); + save[cp - string] = '\0'; + string = save; + if (bitlen < 0 || bitlen > maxbitlen) + bitlen = maxbitlen; + } + else { + bitlen = maxbitlen; + } + + if (family == AF_INET) { + if ((result = my_inet_pton (AF_INET, string, &sin)) <= 0) + return (NULL); + return (New_Prefix (AF_INET, &sin, bitlen)); + } + +#ifdef HAVE_IPV6 + else if (family == AF_INET6) { +// Get rid of this with next IPv6 upgrade +#if defined(NT) && !defined(HAVE_INET_NTOP) + inet6_addr(string, &sin6); + return (New_Prefix (AF_INET6, &sin6, bitlen)); +#else + if ((result = inet_pton (AF_INET6, string, &sin6)) <= 0) + return (NULL); +#endif /* NT */ + return (New_Prefix (AF_INET6, &sin6, bitlen)); + } +#endif /* HAVE_IPV6 */ + else + return (NULL); +} + +prefix_t * +Ref_Prefix (prefix_t * prefix) +{ + if (prefix == NULL) + return (NULL); + if (prefix->ref_count == 0) { + /* make a copy in case of a static prefix */ + return (New_Prefix2 (prefix->family, &prefix->add, prefix->bitlen, NULL)); + } + prefix->ref_count++; +/* fprintf(stderr, "[A %s, %d]\n", prefix_toa (prefix), prefix->ref_count); */ + return (prefix); +} + +void +Deref_Prefix (prefix_t * prefix) +{ + if (prefix == NULL) + return; + /* for secure programming, raise an assert. no static prefix can call this */ + assert (prefix->ref_count > 0); + + prefix->ref_count--; + assert (prefix->ref_count >= 0); + if (prefix->ref_count <= 0) { + Delete (prefix); + return; + } +} + +/* } */ + +/* #define PATRICIA_DEBUG 1 */ + +static int num_active_patricia = 0; + +/* these routines support continuous mask only */ + +patricia_tree_t * +New_Patricia (int maxbits) +{ + patricia_tree_t *patricia = calloc(1, sizeof *patricia); + + patricia->maxbits = maxbits; + patricia->head = NULL; + patricia->num_active_node = 0; + assert (maxbits <= PATRICIA_MAXBITS); /* XXX */ + num_active_patricia++; + return (patricia); +} + + +/* + * if func is supplied, it will be called as func(node->data) + * before deleting the node + */ + +void +Clear_Patricia (patricia_tree_t *patricia, void_fn_t func) +{ + assert (patricia); + if (patricia->head) { + + patricia_node_t *Xstack[PATRICIA_MAXBITS+1]; + patricia_node_t **Xsp = Xstack; + patricia_node_t *Xrn = patricia->head; + + while (Xrn) { + patricia_node_t *l = Xrn->l; + patricia_node_t *r = Xrn->r; + + if (Xrn->prefix) { + Deref_Prefix (Xrn->prefix); + if (Xrn->data && func) + func (Xrn->data); + } + else { + assert (Xrn->data == NULL); + } + Delete (Xrn); + patricia->num_active_node--; + + if (l) { + if (r) { + *Xsp++ = r; + } + Xrn = l; + } else if (r) { + Xrn = r; + } else if (Xsp != Xstack) { + Xrn = *(--Xsp); + } else { + Xrn = (patricia_node_t *) 0; + } + } + } + assert (patricia->num_active_node == 0); + /* Delete (patricia); */ +} + + +void +Destroy_Patricia (patricia_tree_t *patricia, void_fn_t func) +{ + Clear_Patricia (patricia, func); + Delete (patricia); + num_active_patricia--; +} + + +/* + * if func is supplied, it will be called as func(node->prefix, node->data) + */ + +void +patricia_process (patricia_tree_t *patricia, void_fn_t func) +{ + patricia_node_t *node; + assert (func); + + PATRICIA_WALK (patricia->head, node) { + func (node->prefix, node->data); + } PATRICIA_WALK_END; +} + +size_t +patricia_walk_inorder(patricia_node_t *node, void_fn_t func) +{ + size_t n = 0; + assert(func); + + if (node->l) { + n += patricia_walk_inorder(node->l, func); + } + + if (node->prefix) { + func(node->prefix, node->data); + n++; + } + + if (node->r) { + n += patricia_walk_inorder(node->r, func); + } + + return n; +} + + +patricia_node_t * +patricia_search_exact (patricia_tree_t *patricia, prefix_t *prefix) +{ + patricia_node_t *node; + u_char *addr; + u_int bitlen; + + assert (patricia); + assert (prefix); + assert (prefix->bitlen <= patricia->maxbits); + + if (patricia->head == NULL) + return (NULL); + + node = patricia->head; + addr = prefix_touchar (prefix); + bitlen = prefix->bitlen; + + while (node->bit < bitlen) { + + if (BIT_TEST (addr[node->bit >> 3], 0x80 >> (node->bit & 0x07))) { +#ifdef PATRICIA_DEBUG + if (node->prefix) + fprintf (stderr, "patricia_search_exact: take right %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); + else + fprintf (stderr, "patricia_search_exact: take right at %d\n", + node->bit); +#endif /* PATRICIA_DEBUG */ + node = node->r; + } + else { +#ifdef PATRICIA_DEBUG + if (node->prefix) + fprintf (stderr, "patricia_search_exact: take left %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); + else + fprintf (stderr, "patricia_search_exact: take left at %d\n", + node->bit); +#endif /* PATRICIA_DEBUG */ + node = node->l; + } + + if (node == NULL) + return (NULL); + } + +#ifdef PATRICIA_DEBUG + if (node->prefix) + fprintf (stderr, "patricia_search_exact: stop at %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); + else + fprintf (stderr, "patricia_search_exact: stop at %d\n", node->bit); +#endif /* PATRICIA_DEBUG */ + if (node->bit > bitlen || node->prefix == NULL) + return (NULL); + assert (node->bit == bitlen); + assert (node->bit == node->prefix->bitlen); + if (comp_with_mask (prefix_tochar (node->prefix), prefix_tochar (prefix), + bitlen)) { +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_search_exact: found %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); +#endif /* PATRICIA_DEBUG */ + return (node); + } + return (NULL); +} + + +/* if inclusive != 0, "best" may be the given prefix itself */ +patricia_node_t * +patricia_search_best2 (patricia_tree_t *patricia, prefix_t *prefix, int inclusive) +{ + patricia_node_t *node; + patricia_node_t *stack[PATRICIA_MAXBITS + 1]; + u_char *addr; + u_int bitlen; + int cnt = 0; + + assert (patricia); + assert (prefix); + assert (prefix->bitlen <= patricia->maxbits); + + if (patricia->head == NULL) + return (NULL); + + node = patricia->head; + addr = prefix_touchar (prefix); + bitlen = prefix->bitlen; + + while (node->bit < bitlen) { + + if (node->prefix) { +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_search_best: push %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); +#endif /* PATRICIA_DEBUG */ + stack[cnt++] = node; + } + + if (BIT_TEST (addr[node->bit >> 3], 0x80 >> (node->bit & 0x07))) { +#ifdef PATRICIA_DEBUG + if (node->prefix) + fprintf (stderr, "patricia_search_best: take right %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); + else + fprintf (stderr, "patricia_search_best: take right at %d\n", + node->bit); +#endif /* PATRICIA_DEBUG */ + node = node->r; + } + else { +#ifdef PATRICIA_DEBUG + if (node->prefix) + fprintf (stderr, "patricia_search_best: take left %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); + else + fprintf (stderr, "patricia_search_best: take left at %d\n", + node->bit); +#endif /* PATRICIA_DEBUG */ + node = node->l; + } + + if (node == NULL) + break; + } + + if (inclusive && node && node->prefix) + stack[cnt++] = node; + +#ifdef PATRICIA_DEBUG + if (node == NULL) + fprintf (stderr, "patricia_search_best: stop at null\n"); + else if (node->prefix) + fprintf (stderr, "patricia_search_best: stop at %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); + else + fprintf (stderr, "patricia_search_best: stop at %d\n", node->bit); +#endif /* PATRICIA_DEBUG */ + + if (cnt <= 0) + return (NULL); + + while (--cnt >= 0) { + node = stack[cnt]; +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_search_best: pop %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); +#endif /* PATRICIA_DEBUG */ + if (comp_with_mask (prefix_tochar (node->prefix), + prefix_tochar (prefix), + node->prefix->bitlen)) { +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_search_best: found %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); +#endif /* PATRICIA_DEBUG */ + return (node); + } + } + return (NULL); +} + + +patricia_node_t * +patricia_search_best (patricia_tree_t *patricia, prefix_t *prefix) +{ + return (patricia_search_best2 (patricia, prefix, 1)); +} + + +patricia_node_t * +patricia_lookup (patricia_tree_t *patricia, prefix_t *prefix) +{ + patricia_node_t *node, *new_node, *parent, *glue; + u_char *addr, *test_addr; + u_int bitlen, check_bit, differ_bit; + int i, j, r; + + assert (patricia); + assert (prefix); + assert (prefix->bitlen <= patricia->maxbits); + + if (patricia->head == NULL) { + node = calloc(1, sizeof *node); + node->bit = prefix->bitlen; + node->prefix = Ref_Prefix (prefix); + node->parent = NULL; + node->l = node->r = NULL; + node->data = NULL; + patricia->head = node; +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_lookup: new_node #0 %s/%d (head)\n", + prefix_toa (prefix), prefix->bitlen); +#endif /* PATRICIA_DEBUG */ + patricia->num_active_node++; + return (node); + } + + addr = prefix_touchar (prefix); + bitlen = prefix->bitlen; + node = patricia->head; + + while (node->bit < bitlen || node->prefix == NULL) { + + if (node->bit < patricia->maxbits && + BIT_TEST (addr[node->bit >> 3], 0x80 >> (node->bit & 0x07))) { + if (node->r == NULL) + break; +#ifdef PATRICIA_DEBUG + if (node->prefix) + fprintf (stderr, "patricia_lookup: take right %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); + else + fprintf (stderr, "patricia_lookup: take right at %d\n", node->bit); +#endif /* PATRICIA_DEBUG */ + node = node->r; + } + else { + if (node->l == NULL) + break; +#ifdef PATRICIA_DEBUG + if (node->prefix) + fprintf (stderr, "patricia_lookup: take left %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); + else + fprintf (stderr, "patricia_lookup: take left at %d\n", node->bit); +#endif /* PATRICIA_DEBUG */ + node = node->l; + } + + assert (node); + } + + assert (node->prefix); +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_lookup: stop at %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); +#endif /* PATRICIA_DEBUG */ + + test_addr = prefix_touchar (node->prefix); + /* find the first bit different */ + check_bit = (node->bit < bitlen)? node->bit: bitlen; + differ_bit = 0; + for (i = 0; i*8 < check_bit; i++) { + if ((r = (addr[i] ^ test_addr[i])) == 0) { + differ_bit = (i + 1) * 8; + continue; + } + /* I know the better way, but for now */ + for (j = 0; j < 8; j++) { + if (BIT_TEST (r, (0x80 >> j))) + break; + } + /* must be found */ + assert (j < 8); + differ_bit = i * 8 + j; + break; + } + if (differ_bit > check_bit) + differ_bit = check_bit; +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_lookup: differ_bit %d\n", differ_bit); +#endif /* PATRICIA_DEBUG */ + + parent = node->parent; + while (parent && parent->bit >= differ_bit) { + node = parent; + parent = node->parent; +#ifdef PATRICIA_DEBUG + if (node->prefix) + fprintf (stderr, "patricia_lookup: up to %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); + else + fprintf (stderr, "patricia_lookup: up to %d\n", node->bit); +#endif /* PATRICIA_DEBUG */ + } + + if (differ_bit == bitlen && node->bit == bitlen) { + if (node->prefix) { +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_lookup: found %s/%d\n", + prefix_toa (node->prefix), node->prefix->bitlen); +#endif /* PATRICIA_DEBUG */ + return (node); + } + node->prefix = Ref_Prefix (prefix); +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_lookup: new node #1 %s/%d (glue mod)\n", + prefix_toa (prefix), prefix->bitlen); +#endif /* PATRICIA_DEBUG */ + assert (node->data == NULL); + return (node); + } + + new_node = calloc(1, sizeof *new_node); + new_node->bit = prefix->bitlen; + new_node->prefix = Ref_Prefix (prefix); + new_node->parent = NULL; + new_node->l = new_node->r = NULL; + new_node->data = NULL; + patricia->num_active_node++; + + if (node->bit == differ_bit) { + new_node->parent = node; + if (node->bit < patricia->maxbits && + BIT_TEST (addr[node->bit >> 3], 0x80 >> (node->bit & 0x07))) { + assert (node->r == NULL); + node->r = new_node; + } + else { + assert (node->l == NULL); + node->l = new_node; + } +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_lookup: new_node #2 %s/%d (child)\n", + prefix_toa (prefix), prefix->bitlen); +#endif /* PATRICIA_DEBUG */ + return (new_node); + } + + if (bitlen == differ_bit) { + if (bitlen < patricia->maxbits && + BIT_TEST (test_addr[bitlen >> 3], 0x80 >> (bitlen & 0x07))) { + new_node->r = node; + } + else { + new_node->l = node; + } + new_node->parent = node->parent; + if (node->parent == NULL) { + assert (patricia->head == node); + patricia->head = new_node; + } + else if (node->parent->r == node) { + node->parent->r = new_node; + } + else { + node->parent->l = new_node; + } + node->parent = new_node; +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_lookup: new_node #3 %s/%d (parent)\n", + prefix_toa (prefix), prefix->bitlen); +#endif /* PATRICIA_DEBUG */ + } + else { + glue = calloc(1, sizeof *glue); + glue->bit = differ_bit; + glue->prefix = NULL; + glue->parent = node->parent; + glue->data = NULL; + patricia->num_active_node++; + if (differ_bit < patricia->maxbits && + BIT_TEST (addr[differ_bit >> 3], 0x80 >> (differ_bit & 0x07))) { + glue->r = new_node; + glue->l = node; + } + else { + glue->r = node; + glue->l = new_node; + } + new_node->parent = glue; + + if (node->parent == NULL) { + assert (patricia->head == node); + patricia->head = glue; + } + else if (node->parent->r == node) { + node->parent->r = glue; + } + else { + node->parent->l = glue; + } + node->parent = glue; +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_lookup: new_node #4 %s/%d (glue+node)\n", + prefix_toa (prefix), prefix->bitlen); +#endif /* PATRICIA_DEBUG */ + } + return (new_node); +} + + +void +patricia_remove (patricia_tree_t *patricia, patricia_node_t *node) +{ + patricia_node_t *parent, *child; + + assert (patricia); + assert (node); + + if (node->r && node->l) { +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_remove: #0 %s/%d (r & l)\n", + prefix_toa (node->prefix), node->prefix->bitlen); +#endif /* PATRICIA_DEBUG */ + + /* this might be a placeholder node -- have to check and make sure + * there is a prefix aossciated with it ! */ + if (node->prefix != NULL) + Deref_Prefix (node->prefix); + node->prefix = NULL; + /* Also I needed to clear data pointer -- masaki */ + node->data = NULL; + return; + } + + if (node->r == NULL && node->l == NULL) { +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_remove: #1 %s/%d (!r & !l)\n", + prefix_toa (node->prefix), node->prefix->bitlen); +#endif /* PATRICIA_DEBUG */ + parent = node->parent; + Deref_Prefix (node->prefix); + Delete (node); + patricia->num_active_node--; + + if (parent == NULL) { + assert (patricia->head == node); + patricia->head = NULL; + return; + } + + if (parent->r == node) { + parent->r = NULL; + child = parent->l; + } + else { + assert (parent->l == node); + parent->l = NULL; + child = parent->r; + } + + if (parent->prefix) + return; + + /* we need to remove parent too */ + + if (parent->parent == NULL) { + assert (patricia->head == parent); + patricia->head = child; + } + else if (parent->parent->r == parent) { + parent->parent->r = child; + } + else { + assert (parent->parent->l == parent); + parent->parent->l = child; + } + child->parent = parent->parent; + Delete (parent); + patricia->num_active_node--; + return; + } + +#ifdef PATRICIA_DEBUG + fprintf (stderr, "patricia_remove: #2 %s/%d (r ^ l)\n", + prefix_toa (node->prefix), node->prefix->bitlen); +#endif /* PATRICIA_DEBUG */ + if (node->r) { + child = node->r; + } + else { + assert (node->l); + child = node->l; + } + parent = node->parent; + child->parent = parent; + + Deref_Prefix (node->prefix); + Delete (node); + patricia->num_active_node--; + + if (parent == NULL) { + assert (patricia->head == node); + patricia->head = child; + return; + } + + if (parent->r == node) { + parent->r = child; + } + else { + assert (parent->l == node); + parent->l = child; + } +} + +/* { from demo.c */ + +patricia_node_t * +make_and_lookup (patricia_tree_t *tree, char *string) +{ + prefix_t *prefix; + patricia_node_t *node; + + prefix = ascii2prefix (AF_INET, string); + printf ("make_and_lookup: %s/%d\n", prefix_toa (prefix), prefix->bitlen); + node = patricia_lookup (tree, prefix); + Deref_Prefix (prefix); + return (node); +} + +patricia_node_t * +try_search_exact (patricia_tree_t *tree, char *string) +{ + prefix_t *prefix; + patricia_node_t *node; + + prefix = ascii2prefix (AF_INET, string); + printf ("try_search_exact: %s/%d\n", prefix_toa (prefix), prefix->bitlen); + if ((node = patricia_search_exact (tree, prefix)) == NULL) { + printf ("try_search_exact: not found\n"); + } + else { + printf ("try_search_exact: %s/%d found\n", + prefix_toa (node->prefix), node->prefix->bitlen); + } + Deref_Prefix (prefix); + return (node); +} + +void +lookup_then_remove (patricia_tree_t *tree, char *string) +{ + patricia_node_t *node; + + if (node = try_search_exact (tree, string)) + patricia_remove (tree, node); +} + +patricia_node_t * +try_search_best (patricia_tree_t *tree, char *string) +{ + prefix_t *prefix; + patricia_node_t *node; + + prefix = ascii2prefix (AF_INET, string); + printf ("try_search_best: %s/%d\n", prefix_toa (prefix), prefix->bitlen); + if ((node = patricia_search_best (tree, prefix)) == NULL) + printf ("try_search_best: not found\n"); + else + printf ("try_search_best: %s/%d found\n", + prefix_toa (node->prefix), node->prefix->bitlen); + Deref_Prefix (prefix); +} + +/* } */ |