Follow bdb behavior more closely

Default to '.' if we use DB_USE_ENVIRON (or root version) and DB_HOME is not set.
closes #59

git-svn-id: file:///svn/tokudb@793 c7de825b-a66e-492c-adef-691d508d4ae1

src/tests/test_db_env_open_dir_priority.c

+/* Do we open directories with same priority as BDB? i.e. with home, without home, with DB_USE_ENVIRON/etc.. */
+#include <limits.h>
+#include <stdio.h>
+#include <assert.h>
+#include <db.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#define CKERR(r) \
+do {                                                                                                        \
+    if (r!=0) fprintf(stderr, "%s:%d error %d %s\n", __FILE__, __LINE__, r, db_strerror(r)); assert(r==0);  \
+} while (0)
+
+// DIR is defined in the Makefile
+
+#define DB_HOME "DB_HOME"
+#define DBNAME "test.db"
+
+int rootfd;
+char* db_dir;
+char db_name[PATH_MAX];
+int extra_flags;
+char* home;
+
+
+void reinit_config(int set_home, int set_DB_ENVIRON, int set_DB_HOME) {
+    int r = 0;
+    //Return to base dir
+    r = fchdir(rootfd);                 assert(r == 0);
+
+    r = system("rm -rf " DIR);          assert(r == 0);
+    r = mkdir(DIR, 0777);               assert(r == 0);
+    r = chdir(DIR);                     assert(r == 0);
+    unsetenv(DB_HOME);
+
+    if (set_home) {
+        db_dir = "home";
+        r = mkdir(db_dir, 0777);        assert(r == 0);
+    }
+    else if (set_DB_ENVIRON && set_DB_HOME) {
+        db_dir = "DB_HOME";
+        r = mkdir(db_dir, 0777);        assert(r == 0);
+    }
+    else db_dir = ".";
+    
+    if (set_home) home = "home"; else home = NULL;
+    if (set_DB_ENVIRON) extra_flags = DB_USE_ENVIRON; else extra_flags = 0;
+    if (set_DB_HOME) {r = setenv(DB_HOME, DB_HOME, 1);assert(r == 0);}
+
+}
+
+int main() {
+    DB_ENV *env;
+    DB_TXN * const null_txn = 0;
+    DB *db;
+    int r;
+    int i;
+    
+    rootfd = open(".", O_RDONLY, 0); assert(rootfd >= 0);
+    
+    for (i = 0; i < 8; i++) {
+        int set_home = i & 0x1;
+        int set_DB_ENVIRON = i & 0x2;
+        int set_DB_HOME = i & 0x4;
+        
+        reinit_config(set_home, set_DB_ENVIRON, set_DB_HOME);
+        r = snprintf(db_name, sizeof(db_name), "%s/%s", db_dir, DBNAME);
+        assert(r < sizeof(db_name));
+        assert(r >= 0);
+        
+        r = db_env_create(&env, 0);
+        CKERR(r);
+        
+        r = env->open(env, home, DB_CREATE|DB_PRIVATE|DB_INIT_MPOOL|extra_flags, 0);
+// BDB does not check for this. TDB does more error checking.
+#ifdef USE_TDB
+        if (set_home && set_DB_ENVIRON) {
+            assert(r == EINVAL);
+            goto cleanup;
+        }
+        else
+#endif
+            CKERR(r);
+        
+        
+        r = db_create(&db, env, 0);
+        CKERR(r);
+
+        r = db->open(db, null_txn, DBNAME, NULL, DB_BTREE, DB_CREATE, 0666);
+        CKERR(r);
+
+        r = db->close(db, 0);
+        CKERR(r);
+
+        //Verify it went in the right directory.
+    	{
+        	struct stat buf;
+        	r = stat(db_name, &buf);
+        	CKERR(r);
+        }
+#ifdef USE_TDB
+cleanup:
+#endif
+        r = env->close(env, 0);
+        CKERR(r);        
+    }
+
+    r = close(rootfd); assert(r == 0);
+    return 0;
+}

src/ydb.c

@@ -225,17 +225,14 @@ int __toku_db_env_open(DB_ENV * env, const char *home, u_int32_t flags, int mode
         return EINVAL;
 
     if ((flags & DB_USE_ENVIRON) && (flags & DB_USE_ENVIRON_ROOT)) return EINVAL;
-    
 
     if (home) {
         if ((flags & DB_USE_ENVIRON) || (flags & DB_USE_ENVIRON_ROOT)) return EINVAL;
     }
     else if ((flags & DB_USE_ENVIRON) ||
-             ((flags & DB_USE_ENVIRON_ROOT) && geteuid() == 0)) {
-        home = getenv("DB_HOME");
-        if (!home) return EINVAL;
-    }
-    else home = ".";
+             ((flags & DB_USE_ENVIRON_ROOT) && geteuid() == 0)) home = getenv("DB_HOME");
+
+    if (!home) home = ".";
 
 	// Verify that the home exists.
 	{