Finish {{{DB_ENV->log_archive}}}, honoring the oldest live txn. Addresses #83. Fixes #75, #392.

git-svn-id: file:///svn/tokudb@3005 c7de825b-a66e-492c-adef-691d508d4ae1

src/tests/test_archive2.c

+/* Test log archive. */
+#include <db.h>
+#include <sys/stat.h>
+#include "test.h"
+
+int main (int argc, const char *argv[]) {
+    parse_args(argc, argv);
+    DB_ENV *env;
+    DB *db, *db2;
+    DB_TXN *txn, *txn2;
+    DBT key,data;
+    int r;
+
+    system("rm -rf " ENVDIR);
+    r=mkdir(ENVDIR, 0777);       assert(r==0);
+
+    r=db_env_create(&env, 0); CKERR(r);
+    env->set_errfile(env, stderr);
+    r=env->set_lg_max(env, 16000); CKERR(r);
+    r=env->open(env, ENVDIR, DB_INIT_LOCK|DB_INIT_LOG|DB_INIT_MPOOL|DB_INIT_TXN|DB_CREATE|DB_PRIVATE, 0777); CKERR(r);
+
+    r=db_create(&db, env, 0); CKERR(r);
+    r=env->txn_begin(env, 0, &txn, 0); CKERR(r);
+    r=db->open(db, txn, "foo.db", 0, DB_BTREE, DB_CREATE, 0777); CKERR(r);
+    r=txn->commit(txn, 0);    CKERR(r);
+
+    r=db_create(&db2, env, 0); CKERR(r);
+    r=env->txn_begin(env, 0, &txn, 0); CKERR(r);
+    r=db->open(db2, txn, "foo2.db", 0, DB_BTREE, DB_CREATE, 0777); CKERR(r);
+    r=txn->commit(txn, 0);    CKERR(r);
+
+    r=env->txn_begin(env, 0, &txn2, 0); CKERR(r);
+    r=db->put(db2, txn2, dbt_init(&key, "what", 5), dbt_init(&data, "who", 4), 0);  CKERR(r);
+
+    int i;
+    for (i=0; i<100; i++) {
+	char hello[30],there[30];
+	snprintf(hello, sizeof(hello), "hello%d", i);
+	snprintf(there, sizeof(there), "there%d", i);
+
+	r=env->txn_begin(env, 0, &txn, 0); CKERR(r);
+	r=db->put(db, txn,
+		  dbt_init(&key,  hello, strlen(hello)+1),
+		  dbt_init(&data, there, strlen(there)+1),
+		  0);
+	r=txn->commit(txn, 0);    CKERR(r);
+	r=env->txn_checkpoint(env, 0, 0, 0);
+    }
+
+    {
+	char **list;
+	r=env->log_archive(env, &list, 0);
+	CKERR(r);
+	assert(list==0); // since there is an open txn
+    }
+
+    r=txn2->commit(txn2, 0); CKERR(r);
+
+    r=db->close(db, 0); CKERR(r);
+    r=env->close(env, 0); CKERR(r);
+    return 0;
+}