bird/nest/a-set.c
Alexander Zubkov 0e1fd7ea6a Filter: Add operators to find minimum and maximum element of sets
Add operators .min and .max to find minumum or maximum element in sets
of types: clist, eclist, lclist. Example usage:

bgp_community.min
bgp_ext_community.max
filter(bgp_large_community, [(as1, as2, *)]).min

Signed-off-by: Alexander Zubkov <green@qrator.net>
2021-12-28 04:07:09 +01:00

695 lines
14 KiB
C

/*
* BIRD -- Set/Community-list Operations
*
* (c) 2000 Martin Mares <mj@ucw.cz>
* (c) 2000 Pavel Machek <pavel@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#include <stdlib.h>
#include "nest/bird.h"
#include "nest/route.h"
#include "nest/attrs.h"
#include "lib/resource.h"
#include "lib/string.h"
/**
* int_set_format - format an &set for printing
* @set: set attribute to be formatted
* @way: style of format (0 for router ID list, 1 for community list)
* @from: starting position in set
* @buf: destination buffer
* @size: size of buffer
*
* This function takes a set attribute and formats it. @way specifies
* the style of format (router ID / community). @from argument can be
* used to specify the first printed value for the purpose of printing
* untruncated sets even with smaller buffers. If the output fits in
* the buffer, 0 is returned, otherwise the position of the first not
* printed item is returned. This value can be used as @from argument
* in subsequent calls. If truncated output suffices, -1 can be
* instead used as @from, in that case " ..." is eventually added at
* the buffer to indicate truncation.
*/
int
int_set_format(const struct adata *set, int way, int from, byte *buf, uint size)
{
u32 *z = (u32 *) set->data;
byte *end = buf + size - 24;
int from2 = MAX(from, 0);
int to = set->length / 4;
int i;
for (i = from2; i < to; i++)
{
if (buf > end)
{
if (from < 0)
strcpy(buf, " ...");
else
*buf = 0;
return i;
}
if (i > from2)
*buf++ = ' ';
if (way)
buf += bsprintf(buf, "(%d,%d)", z[i] >> 16, z[i] & 0xffff);
else
buf += bsprintf(buf, "%R", z[i]);
}
*buf = 0;
return 0;
}
int
ec_format(byte *buf, u64 ec)
{
u32 type, key, val;
char tbuf[16];
const char *kind;
type = ec >> 48;
kind = ec_subtype_str(type & 0xf0ff);
if (!kind) {
bsprintf(tbuf, "unknown 0x%x", type);
kind = tbuf;
}
switch (ec >> 56)
{
/* RFC 4360 3.1. Two-Octet AS Specific Extended Community */
case 0x00:
case 0x40:
key = (ec >> 32) & 0xFFFF;
val = ec;
return bsprintf(buf, "(%s, %u, %u)", kind, key, val);
/* RFC 4360 3.2. IPv4 Address Specific Extended Community */
case 0x01:
case 0x41:
key = ec >> 16;
val = ec & 0xFFFF;
return bsprintf(buf, "(%s, %R, %u)", kind, key, val);
/* RFC 5668 4-Octet AS Specific BGP Extended Community */
case 0x02:
case 0x42:
key = ec >> 16;
val = ec & 0xFFFF;
return bsprintf(buf, "(%s, %u, %u)", kind, key, val);
/* Generic format for unknown kinds of extended communities */
default:
key = ec >> 32;
val = ec;
return bsprintf(buf, "(generic, 0x%x, 0x%x)", key, val);
}
}
int
ec_set_format(const struct adata *set, int from, byte *buf, uint size)
{
u32 *z = int_set_get_data(set);
byte *end = buf + size - 64;
int from2 = MAX(from, 0);
int to = int_set_get_size(set);
int i;
for (i = from2; i < to; i += 2)
{
if (buf > end)
{
if (from < 0)
strcpy(buf, " ...");
else
*buf = 0;
return i;
}
if (i > from2)
*buf++ = ' ';
buf += ec_format(buf, ec_get(z, i));
}
*buf = 0;
return 0;
}
int
lc_format(byte *buf, lcomm lc)
{
return bsprintf(buf, "(%u, %u, %u)", lc.asn, lc.ldp1, lc.ldp2);
}
int
lc_set_format(const struct adata *set, int from, byte *buf, uint bufsize)
{
u32 *d = (u32 *) set->data;
byte *end = buf + bufsize - 64;
int from2 = MAX(from, 0);
int to = set->length / 4;
int i;
for (i = from2; i < to; i += 3)
{
if (buf > end)
{
if (from < 0)
strcpy(buf, "...");
else
buf[-1] = 0;
return i;
}
buf += bsprintf(buf, "(%u, %u, %u)", d[i], d[i+1], d[i+2]);
*buf++ = ' ';
}
if (i != from2)
buf--;
*buf = 0;
return 0;
}
int
int_set_contains(const struct adata *list, u32 val)
{
if (!list)
return 0;
u32 *l = (u32 *) list->data;
int len = int_set_get_size(list);
int i;
for (i = 0; i < len; i++)
if (*l++ == val)
return 1;
return 0;
}
int
ec_set_contains(const struct adata *list, u64 val)
{
if (!list)
return 0;
u32 *l = int_set_get_data(list);
int len = int_set_get_size(list);
u32 eh = ec_hi(val);
u32 el = ec_lo(val);
int i;
for (i=0; i < len; i += 2)
if (l[i] == eh && l[i+1] == el)
return 1;
return 0;
}
int
lc_set_contains(const struct adata *list, lcomm val)
{
if (!list)
return 0;
u32 *l = int_set_get_data(list);
int len = int_set_get_size(list);
int i;
for (i = 0; i < len; i += 3)
if (lc_match(l, i, val))
return 1;
return 0;
}
const struct adata *
int_set_prepend(struct linpool *pool, const struct adata *list, u32 val)
{
struct adata *res;
int len;
if (int_set_contains(list, val))
return list;
len = list ? list->length : 0;
res = lp_alloc(pool, sizeof(struct adata) + len + 4);
res->length = len + 4;
if (list)
memcpy(res->data + 4, list->data, list->length);
* (u32 *) res->data = val;
return res;
}
const struct adata *
int_set_add(struct linpool *pool, const struct adata *list, u32 val)
{
struct adata *res;
int len;
if (int_set_contains(list, val))
return list;
len = list ? list->length : 0;
res = lp_alloc(pool, sizeof(struct adata) + len + 4);
res->length = len + 4;
if (list)
memcpy(res->data, list->data, list->length);
* (u32 *) (res->data + len) = val;
return res;
}
const struct adata *
ec_set_add(struct linpool *pool, const struct adata *list, u64 val)
{
if (ec_set_contains(list, val))
return list;
int olen = list ? list->length : 0;
struct adata *res = lp_alloc(pool, sizeof(struct adata) + olen + 8);
res->length = olen + 8;
if (list)
memcpy(res->data, list->data, list->length);
u32 *l = (u32 *) (res->data + olen);
l[0] = ec_hi(val);
l[1] = ec_lo(val);
return res;
}
const struct adata *
lc_set_add(struct linpool *pool, const struct adata *list, lcomm val)
{
if (lc_set_contains(list, val))
return list;
int olen = list ? list->length : 0;
struct adata *res = lp_alloc(pool, sizeof(struct adata) + olen + LCOMM_LENGTH);
res->length = olen + LCOMM_LENGTH;
if (list)
memcpy(res->data, list->data, list->length);
lc_put((u32 *) (res->data + olen), val);
return res;
}
const struct adata *
int_set_del(struct linpool *pool, const struct adata *list, u32 val)
{
if (!int_set_contains(list, val))
return list;
struct adata *res;
res = lp_alloc(pool, sizeof(struct adata) + list->length - 4);
res->length = list->length - 4;
u32 *l = int_set_get_data(list);
u32 *k = int_set_get_data(res);
int len = int_set_get_size(list);
int i;
for (i = 0; i < len; i++)
if (l[i] != val)
*k++ = l[i];
return res;
}
const struct adata *
ec_set_del(struct linpool *pool, const struct adata *list, u64 val)
{
if (!ec_set_contains(list, val))
return list;
struct adata *res;
res = lp_alloc(pool, sizeof(struct adata) + list->length - 8);
res->length = list->length - 8;
u32 *l = int_set_get_data(list);
u32 *k = int_set_get_data(res);
int len = int_set_get_size(list);
u32 eh = ec_hi(val);
u32 el = ec_lo(val);
int i;
for (i=0; i < len; i += 2)
if (! (l[i] == eh && l[i+1] == el))
{
*k++ = l[i];
*k++ = l[i+1];
}
return res;
}
const struct adata *
lc_set_del(struct linpool *pool, const struct adata *list, lcomm val)
{
if (!lc_set_contains(list, val))
return list;
struct adata *res;
res = lp_alloc(pool, sizeof(struct adata) + list->length - LCOMM_LENGTH);
res->length = list->length - LCOMM_LENGTH;
u32 *l = int_set_get_data(list);
u32 *k = int_set_get_data(res);
int len = int_set_get_size(list);
int i;
for (i=0; i < len; i += 3)
if (! lc_match(l, i, val))
k = lc_copy(k, l+i);
return res;
}
const struct adata *
int_set_union(struct linpool *pool, const struct adata *l1, const struct adata *l2)
{
if (!l1)
return l2;
if (!l2)
return l1;
struct adata *res;
int len = int_set_get_size(l2);
u32 *l = int_set_get_data(l2);
u32 tmp[len];
u32 *k = tmp;
int i;
for (i = 0; i < len; i++)
if (!int_set_contains(l1, l[i]))
*k++ = l[i];
if (k == tmp)
return l1;
len = (k - tmp) * 4;
res = lp_alloc(pool, sizeof(struct adata) + l1->length + len);
res->length = l1->length + len;
memcpy(res->data, l1->data, l1->length);
memcpy(res->data + l1->length, tmp, len);
return res;
}
const struct adata *
ec_set_union(struct linpool *pool, const struct adata *l1, const struct adata *l2)
{
if (!l1)
return l2;
if (!l2)
return l1;
struct adata *res;
int len = int_set_get_size(l2);
u32 *l = int_set_get_data(l2);
u32 tmp[len];
u32 *k = tmp;
int i;
for (i = 0; i < len; i += 2)
if (!ec_set_contains(l1, ec_get(l, i)))
{
*k++ = l[i];
*k++ = l[i+1];
}
if (k == tmp)
return l1;
len = (k - tmp) * 4;
res = lp_alloc(pool, sizeof(struct adata) + l1->length + len);
res->length = l1->length + len;
memcpy(res->data, l1->data, l1->length);
memcpy(res->data + l1->length, tmp, len);
return res;
}
const struct adata *
lc_set_union(struct linpool *pool, const struct adata *l1, const struct adata *l2)
{
if (!l1)
return l2;
if (!l2)
return l1;
struct adata *res;
int len = int_set_get_size(l2);
u32 *l = int_set_get_data(l2);
u32 tmp[len];
u32 *k = tmp;
int i;
for (i = 0; i < len; i += 3)
if (!lc_set_contains(l1, lc_get(l, i)))
k = lc_copy(k, l+i);
if (k == tmp)
return l1;
len = (k - tmp) * 4;
res = lp_alloc(pool, sizeof(struct adata) + l1->length + len);
res->length = l1->length + len;
memcpy(res->data, l1->data, l1->length);
memcpy(res->data + l1->length, tmp, len);
return res;
}
struct adata *
ec_set_del_nontrans(struct linpool *pool, const struct adata *set)
{
adata *res = lp_alloc_adata(pool, set->length);
u32 *src = int_set_get_data(set);
u32 *dst = int_set_get_data(res);
int len = int_set_get_size(set);
int i;
/* Remove non-transitive communities (EC_TBIT set) */
for (i = 0; i < len; i += 2)
{
if (src[i] & EC_TBIT)
continue;
*dst++ = src[i];
*dst++ = src[i+1];
}
res->length = ((byte *) dst) - res->data;
return res;
}
static int
int_set_cmp(const void *X, const void *Y)
{
const u32 *x = X, *y = Y;
return (*x < *y) ? -1 : (*x > *y) ? 1 : 0;
}
struct adata *
int_set_sort(struct linpool *pool, const struct adata *src)
{
struct adata *dst = lp_alloc_adata(pool, src->length);
memcpy(dst->data, src->data, src->length);
qsort(dst->data, dst->length / 4, 4, int_set_cmp);
return dst;
}
int
int_set_min(const struct adata *list, u32 *val)
{
if (!list)
return 0;
u32 *l = (u32 *) list->data;
int len = int_set_get_size(list);
int i;
if (len < 1)
return 0;
*val = *l++;
for (i = 1; i < len; i++, l++)
if (int_set_cmp(val, l) > 0)
*val = *l;
return 1;
}
int
int_set_max(const struct adata *list, u32 *val)
{
if (!list)
return 0;
u32 *l = (u32 *) list->data;
int len = int_set_get_size(list);
int i;
if (len < 1)
return 0;
*val = *l++;
for (i = 1; i < len; i++, l++)
if (int_set_cmp(val, l) < 0)
*val = *l;
return 1;
}
static int
ec_set_cmp(const void *X, const void *Y)
{
u64 x = ec_get(X, 0);
u64 y = ec_get(Y, 0);
return (x < y) ? -1 : (x > y) ? 1 : 0;
}
struct adata *
ec_set_sort(struct linpool *pool, const struct adata *src)
{
struct adata *dst = lp_alloc_adata(pool, src->length);
memcpy(dst->data, src->data, src->length);
qsort(dst->data, dst->length / 8, 8, ec_set_cmp);
return dst;
}
void
ec_set_sort_x(struct adata *set)
{
/* Sort in place */
qsort(set->data, set->length / 8, 8, ec_set_cmp);
}
int
ec_set_min(const struct adata *list, u64 *val)
{
if (!list)
return 0;
u32 *l = int_set_get_data(list);
int len = int_set_get_size(list);
int i;
if (len < 1)
return 0;
u32 *res = l; l += 2;
for (i = 2; i < len; i += 2, l += 2)
if (ec_set_cmp(res, l) > 0)
res = l;
*val = ec_generic(res[0], res[1]);
return 1;
}
int
ec_set_max(const struct adata *list, u64 *val)
{
if (!list)
return 0;
u32 *l = int_set_get_data(list);
int len = int_set_get_size(list);
int i;
if (len < 1)
return 0;
u32 *res = l; l += 2;
for (i = 2; i < len; i += 2, l += 2)
if (ec_set_cmp(res, l) < 0)
res = l;
*val = ec_generic(res[0], res[1]);
return 1;
}
static int
lc_set_cmp(const void *X, const void *Y)
{
const u32 *x = X, *y = Y;
if (x[0] != y[0])
return (x[0] > y[0]) ? 1 : -1;
if (x[1] != y[1])
return (x[1] > y[1]) ? 1 : -1;
if (x[2] != y[2])
return (x[2] > y[2]) ? 1 : -1;
return 0;
}
struct adata *
lc_set_sort(struct linpool *pool, const struct adata *src)
{
struct adata *dst = lp_alloc_adata(pool, src->length);
memcpy(dst->data, src->data, src->length);
qsort(dst->data, dst->length / LCOMM_LENGTH, LCOMM_LENGTH, lc_set_cmp);
return dst;
}
int
lc_set_min(const struct adata *list, lcomm *val)
{
if (!list)
return 0;
u32 *l = int_set_get_data(list);
int len = int_set_get_size(list);
int i;
if (len < 1)
return 0;
u32 *res = l; l += 3;
for (i = 3; i < len; i += 3, l += 3)
if (lc_set_cmp(res, l) > 0)
res = l;
*val = (lcomm) { res[0], res[1], res[2] };
return 1;
}
int
lc_set_max(const struct adata *list, lcomm *val)
{
if (!list)
return 0;
u32 *l = int_set_get_data(list);
int len = int_set_get_size(list);
int i;
if (len < 1)
return 0;
u32 *res = l; l += 3;
for (i = 3; i < len; i += 3, l += 3)
if (lc_set_cmp(res, l) < 0)
res = l;
*val = (lcomm) { res[0], res[1], res[2] };
return 1;
}