--- /dev/null
+/** @file midl.c
+ * @brief ldap bdb back-end ID List functions */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2000-2021 The OpenLDAP Foundation.
+ * Portions Copyright 2001-2021 Howard Chu, Symas Corp.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
+
+#include <limits.h>
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <sys/types.h>
+#include "midl.h"
+
+/** @defgroup internal LMDB Internals
+ * @{
+ */
+/** @defgroup idls ID List Management
+ * @{
+ */
+#define CMP(x,y) ( (x) < (y) ? -1 : (x) > (y) )
+
+unsigned mdb_midl_search( MDB_IDL ids, MDB_ID id )
+{
+ /*
+ * binary search of id in ids
+ * if found, returns position of id
+ * if not found, returns first position greater than id
+ */
+ unsigned base = 0;
+ unsigned cursor = 1;
+ int val = 0;
+ unsigned n = ids[0];
+
+ while( 0 < n ) {
+ unsigned pivot = n >> 1;
+ cursor = base + pivot + 1;
+ val = CMP( ids[cursor], id );
+
+ if( val < 0 ) {
+ n = pivot;
+
+ } else if ( val > 0 ) {
+ base = cursor;
+ n -= pivot + 1;
+
+ } else {
+ return cursor;
+ }
+ }
+
+ if( val > 0 ) {
+ ++cursor;
+ }
+ return cursor;
+}
+
+#if 0 /* superseded by append/sort */
+int mdb_midl_insert( MDB_IDL ids, MDB_ID id )
+{
+ unsigned x, i;
+
+ x = mdb_midl_search( ids, id );
+ assert( x > 0 );
+
+ if( x < 1 ) {
+ /* internal error */
+ return -2;
+ }
+
+ if ( x <= ids[0] && ids[x] == id ) {
+ /* duplicate */
+ assert(0);
+ return -1;
+ }
+
+ if ( ++ids[0] >= MDB_IDL_DB_MAX ) {
+ /* no room */
+ --ids[0];
+ return -2;
+
+ } else {
+ /* insert id */
+ for (i=ids[0]; i>x; i--)
+ ids[i] = ids[i-1];
+ ids[x] = id;
+ }
+
+ return 0;
+}
+#endif
+
+MDB_IDL mdb_midl_alloc(int num)
+{
+ MDB_IDL ids = malloc((num+2) * sizeof(MDB_ID));
+ if (ids) {
+ *ids++ = num;
+ *ids = 0;
+ }
+ return ids;
+}
+
+void mdb_midl_free(MDB_IDL ids)
+{
+ if (ids)
+ free(ids-1);
+}
+
+void mdb_midl_shrink( MDB_IDL *idp )
+{
+ MDB_IDL ids = *idp;
+ if (*(--ids) > MDB_IDL_UM_MAX &&
+ (ids = realloc(ids, (MDB_IDL_UM_MAX+2) * sizeof(MDB_ID))))
+ {
+ *ids++ = MDB_IDL_UM_MAX;
+ *idp = ids;
+ }
+}
+
+static int mdb_midl_grow( MDB_IDL *idp, int num )
+{
+ MDB_IDL idn = *idp-1;
+ /* grow it */
+ idn = realloc(idn, (*idn + num + 2) * sizeof(MDB_ID));
+ if (!idn)
+ return ENOMEM;
+ *idn++ += num;
+ *idp = idn;
+ return 0;
+}
+
+int mdb_midl_need( MDB_IDL *idp, unsigned num )
+{
+ MDB_IDL ids = *idp;
+ num += ids[0];
+ if (num > ids[-1]) {
+ num = (num + num/4 + (256 + 2)) & -256;
+ if (!(ids = realloc(ids-1, num * sizeof(MDB_ID))))
+ return ENOMEM;
+ *ids++ = num - 2;
+ *idp = ids;
+ }
+ return 0;
+}
+
+int mdb_midl_append( MDB_IDL *idp, MDB_ID id )
+{
+ MDB_IDL ids = *idp;
+ /* Too big? */
+ if (ids[0] >= ids[-1]) {
+ if (mdb_midl_grow(idp, MDB_IDL_UM_MAX))
+ return ENOMEM;
+ ids = *idp;
+ }
+ ids[0]++;
+ ids[ids[0]] = id;
+ return 0;
+}
+
+int mdb_midl_append_list( MDB_IDL *idp, MDB_IDL app )
+{
+ MDB_IDL ids = *idp;
+ /* Too big? */
+ if (ids[0] + app[0] >= ids[-1]) {
+ if (mdb_midl_grow(idp, app[0]))
+ return ENOMEM;
+ ids = *idp;
+ }
+ memcpy(&ids[ids[0]+1], &app[1], app[0] * sizeof(MDB_ID));
+ ids[0] += app[0];
+ return 0;
+}
+
+int mdb_midl_append_range( MDB_IDL *idp, MDB_ID id, unsigned n )
+{
+ MDB_ID *ids = *idp, len = ids[0];
+ /* Too big? */
+ if (len + n > ids[-1]) {
+ if (mdb_midl_grow(idp, n | MDB_IDL_UM_MAX))
+ return ENOMEM;
+ ids = *idp;
+ }
+ ids[0] = len + n;
+ ids += len;
+ while (n)
+ ids[n--] = id++;
+ return 0;
+}
+
+void mdb_midl_xmerge( MDB_IDL idl, MDB_IDL merge )
+{
+ MDB_ID old_id, merge_id, i = merge[0], j = idl[0], k = i+j, total = k;
+ idl[0] = (MDB_ID)-1; /* delimiter for idl scan below */
+ old_id = idl[j];
+ while (i) {
+ merge_id = merge[i--];
+ for (; old_id < merge_id; old_id = idl[--j])
+ idl[k--] = old_id;
+ idl[k--] = merge_id;
+ }
+ idl[0] = total;
+}
+
+/* Quicksort + Insertion sort for small arrays */
+
+#define SMALL 8
+#define MIDL_SWAP(a,b) { itmp=(a); (a)=(b); (b)=itmp; }
+
+void
+mdb_midl_sort( MDB_IDL ids )
+{
+ /* Max possible depth of int-indexed tree * 2 items/level */
+ int istack[sizeof(int)*CHAR_BIT * 2];
+ int i,j,k,l,ir,jstack;
+ MDB_ID a, itmp;
+
+ ir = (int)ids[0];
+ l = 1;
+ jstack = 0;
+ for(;;) {
+ if (ir - l < SMALL) { /* Insertion sort */
+ for (j=l+1;j<=ir;j++) {
+ a = ids[j];
+ for (i=j-1;i>=1;i--) {
+ if (ids[i] >= a) break;
+ ids[i+1] = ids[i];
+ }
+ ids[i+1] = a;
+ }
+ if (jstack == 0) break;
+ ir = istack[jstack--];
+ l = istack[jstack--];
+ } else {
+ k = (l + ir) >> 1; /* Choose median of left, center, right */
+ MIDL_SWAP(ids[k], ids[l+1]);
+ if (ids[l] < ids[ir]) {
+ MIDL_SWAP(ids[l], ids[ir]);
+ }
+ if (ids[l+1] < ids[ir]) {
+ MIDL_SWAP(ids[l+1], ids[ir]);
+ }
+ if (ids[l] < ids[l+1]) {
+ MIDL_SWAP(ids[l], ids[l+1]);
+ }
+ i = l+1;
+ j = ir;
+ a = ids[l+1];
+ for(;;) {
+ do i++; while(ids[i] > a);
+ do j--; while(ids[j] < a);
+ if (j < i) break;
+ MIDL_SWAP(ids[i],ids[j]);
+ }
+ ids[l+1] = ids[j];
+ ids[j] = a;
+ jstack += 2;
+ if (ir-i+1 >= j-l) {
+ istack[jstack] = ir;
+ istack[jstack-1] = i;
+ ir = j-1;
+ } else {
+ istack[jstack] = j-1;
+ istack[jstack-1] = l;
+ l = i;
+ }
+ }
+ }
+}
+
+unsigned mdb_mid2l_search( MDB_ID2L ids, MDB_ID id )
+{
+ /*
+ * binary search of id in ids
+ * if found, returns position of id
+ * if not found, returns first position greater than id
+ */
+ unsigned base = 0;
+ unsigned cursor = 1;
+ int val = 0;
+ unsigned n = (unsigned)ids[0].mid;
+
+ while( 0 < n ) {
+ unsigned pivot = n >> 1;
+ cursor = base + pivot + 1;
+ val = CMP( id, ids[cursor].mid );
+
+ if( val < 0 ) {
+ n = pivot;
+
+ } else if ( val > 0 ) {
+ base = cursor;
+ n -= pivot + 1;
+
+ } else {
+ return cursor;
+ }
+ }
+
+ if( val > 0 ) {
+ ++cursor;
+ }
+ return cursor;
+}
+
+int mdb_mid2l_insert( MDB_ID2L ids, MDB_ID2 *id )
+{
+ unsigned x, i;
+
+ x = mdb_mid2l_search( ids, id->mid );
+
+ if( x < 1 ) {
+ /* internal error */
+ return -2;
+ }
+
+ if ( x <= ids[0].mid && ids[x].mid == id->mid ) {
+ /* duplicate */
+ return -1;
+ }
+
+ if ( ids[0].mid >= MDB_IDL_UM_MAX ) {
+ /* too big */
+ return -2;
+
+ } else {
+ /* insert id */
+ ids[0].mid++;
+ for (i=(unsigned)ids[0].mid; i>x; i--)
+ ids[i] = ids[i-1];
+ ids[x] = *id;
+ }
+
+ return 0;
+}
+
+int mdb_mid2l_append( MDB_ID2L ids, MDB_ID2 *id )
+{
+ /* Too big? */
+ if (ids[0].mid >= MDB_IDL_UM_MAX) {
+ return -2;
+ }
+ ids[0].mid++;
+ ids[ids[0].mid] = *id;
+ return 0;
+}
+
+#ifdef MDB_VL32
+unsigned mdb_mid3l_search( MDB_ID3L ids, MDB_ID id )
+{
+ /*
+ * binary search of id in ids
+ * if found, returns position of id
+ * if not found, returns first position greater than id
+ */
+ unsigned base = 0;
+ unsigned cursor = 1;
+ int val = 0;
+ unsigned n = (unsigned)ids[0].mid;
+
+ while( 0 < n ) {
+ unsigned pivot = n >> 1;
+ cursor = base + pivot + 1;
+ val = CMP( id, ids[cursor].mid );
+
+ if( val < 0 ) {
+ n = pivot;
+
+ } else if ( val > 0 ) {
+ base = cursor;
+ n -= pivot + 1;
+
+ } else {
+ return cursor;
+ }
+ }
+
+ if( val > 0 ) {
+ ++cursor;
+ }
+ return cursor;
+}
+
+int mdb_mid3l_insert( MDB_ID3L ids, MDB_ID3 *id )
+{
+ unsigned x, i;
+
+ x = mdb_mid3l_search( ids, id->mid );
+
+ if( x < 1 ) {
+ /* internal error */
+ return -2;
+ }
+
+ if ( x <= ids[0].mid && ids[x].mid == id->mid ) {
+ /* duplicate */
+ return -1;
+ }
+
+ /* insert id */
+ ids[0].mid++;
+ for (i=(unsigned)ids[0].mid; i>x; i--)
+ ids[i] = ids[i-1];
+ ids[x] = *id;
+
+ return 0;
+}
+#endif /* MDB_VL32 */
+
+/** @} */
+/** @} */
projects / ziglmdb / blobdiff