This is a multi-part message in MIME format. --------------010901030100040802060200 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit On Sunday, January 24, 2016 07:44 PM, Howard Chu wrote: Thank you. It now works except for the case when the deleted record is just before the end of the database. In this case the next call to cursor get with MDB_NEXT / MDB_NEXT_DUP will still hang the program, instead of returning not found (or other errors). (It seems to be stuck at some wait state without heavy cpu usage). I attach a version of mtest3.c modified to show the issue. --------------010901030100040802060200 Content-Type: text/x-csrc; name="mtest3.c" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename="mtest3.c" /* mtest3.c - memory-mapped database tester/toy */ /* * Copyright 2011-2015 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>;. */ /* Tests for sorted duplicate DBs with cursor delete */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <time.h> #include "lmdb.h" #define E(expr) CHECK((rc = (expr)) == MDB_SUCCESS, #expr) #define RES(err, expr) ((rc = expr) == (err) || (CHECK(!rc, #expr), 0)) #define CHECK(test, msg) ((test) ? (void)0 : ((void)fprintf(stderr, \ "%s:%d: %s: %s\n", __FILE__, __LINE__, msg, mdb_strerror(rc)), abort())) int main(int argc,char * argv[]) { int i = 0, j = 0, rc; MDB_env *env; MDB_dbi dbi; MDB_val key, data; MDB_txn *txn; MDB_stat mst; MDB_cursor *cursor; int count; int *values; char sval[32]; char kval[sizeof(int)]; srand(time(NULL)); memset(sval, 0, sizeof(sval)); count = 10; values = (int *)malloc(count*sizeof(int)); for(i = 0;i<count;i++) { values[i]= i * 10; } E(mdb_env_create(&env)); E(mdb_env_set_mapsize(env, 10485760)); E(mdb_env_set_maxdbs(env, 4)); E(mdb_env_open(env, "./testdb", MDB_FIXEDMAP|MDB_NOSYNC, 0664)); E(mdb_txn_begin(env, NULL, 0, &txn)); E(mdb_dbi_open(txn, "id2", MDB_CREATE|MDB_DUPSORT, &dbi)); key.mv_size = sizeof(int); key.mv_data = kval; data.mv_size = sizeof(sval); data.mv_data = sval; printf("Adding %d values\n", count); for (i=0;i<count;i++) { if (!(i & 0x07)) sprintf(kval, "%03x", values[i]); sprintf(sval, "%03x %d foo bar", values[i], values[i]); if (RES(MDB_KEYEXIST, mdb_put(txn, dbi, &key, &data, MDB_NODUPDATA))) j++; } if (j) printf("%d duplicates skipped\n", j); E(mdb_txn_commit(txn)); E(mdb_env_stat(env, &mst)); E(mdb_txn_begin(env, NULL, MDB_RDONLY, &txn)); E(mdb_cursor_open(txn, dbi, &cursor)); while ((rc = mdb_cursor_get(cursor, &key, &data, MDB_NEXT)) == 0) { printf("key: %p %.*s, data: %p %.*s\n", key.mv_data, (int) key.mv_size, (char *) key.mv_data, data.mv_data, (int) data.mv_size, (char *) data.mv_data); } CHECK(rc == MDB_NOTFOUND, "mdb_cursor_get"); mdb_cursor_close(cursor); mdb_txn_abort(txn); E(mdb_env_stat(env, &mst)); E(mdb_txn_begin(env, NULL, 0, &txn)); E(mdb_cursor_open(txn, dbi, &cursor)); /* * There are 2 items with key = values[8] at the end of the list */ sprintf(kval, "%03x", values[8]); key.mv_size = sizeof(int); key.mv_data = kval; printf("\nCursor set / first dup\n"); E(mdb_cursor_get(cursor, &key, &data, MDB_SET_KEY)); E(mdb_cursor_get(cursor, &key, &data, MDB_FIRST_DUP)); printf("key: %.*s, data: %.*s\n", (int) key.mv_size, (char *) key.mv_data, (int) data.mv_size, (char *) data.mv_data); printf("Cursor next\n"); j=0; /* * The program will hang at the following mdb_cursor_get * after cursor delete */ while ((rc = mdb_cursor_get(cursor, &key, &data, MDB_NEXT_DUP)) == 0) { printf("key: %.*s, data: %.*s\n", (int) key.mv_size, (char *) key.mv_data, (int) data.mv_size, (char *) data.mv_data); j++; if (j == 1) { printf("delete the above key/data\n"); if (RES(MDB_NOTFOUND, mdb_cursor_del(cursor, 0))) { mdb_cursor_close(cursor); mdb_txn_abort(txn); break; } } if (j > count) { printf("Should not be there\n"); break; } } if (j > 1) { mdb_cursor_close(cursor); E(mdb_txn_commit(txn)); } E(mdb_txn_begin(env, NULL, 0, &txn)); E(mdb_cursor_open(txn, dbi, &cursor)); sprintf(kval, "%03x", values[0]); key.mv_size = sizeof(int); key.mv_data = kval; printf("\nCursor set / last dup\n"); E(mdb_cursor_get(cursor, &key, &data, MDB_SET_KEY)); E(mdb_cursor_get(cursor, &key, &data, MDB_LAST_DUP)); printf("key: %.*s, data: %.*s\n", (int) key.mv_size, (char *) key.mv_data, (int) data.mv_size, (char *) data.mv_data); printf("Cursor prev\n"); j=0; while ((rc = mdb_cursor_get(cursor, &key, &data, MDB_PREV_DUP)) == 0) { printf("key: %.*s, data: %.*s\n", (int) key.mv_size, (char *) key.mv_data, (int) data.mv_size, (char *) data.mv_data); j++; if (j == 1) { printf("Delete the above key/data\n"); if (RES(MDB_NOTFOUND, mdb_cursor_del(cursor, 0))) { mdb_cursor_close(cursor); mdb_txn_abort(txn); break; } } if (j > count) { printf("Should not be there\n"); break; } } if (j > 1) { mdb_cursor_close(cursor); E(mdb_txn_commit(txn)); } mdb_dbi_close(env, dbi); mdb_env_close(env); free (values); return 0; } --------------010901030100040802060200--