Make db_create work under c++. Addresses #197.

git-svn-id: file:///svn/tokudb@1194 c7de825b-a66e-492c-adef-691d508d4ae1

buildheader/db.h_4_4

@@ -43,6 +43,7 @@ typedef enum {
 #define DB_ARCH_ABS 1
 #define DB_ARCH_LOG 4
 #define DB_CREATE 1
+#define DB_CXX_NO_EXCEPTIONS 1
 #define DB_EXCL 8192
 #define DB_PRIVATE 1048576
 #define DB_RDONLY 16

buildheader/make_db_h.c

@@ -44,6 +44,7 @@ void print_defines (void) {
     dodefine(DB_ARCH_LOG);
 
     dodefine(DB_CREATE);
+    dodefine(DB_CXX_NO_EXCEPTIONS);
     dodefine(DB_EXCL);
     dodefine(DB_PRIVATE);
     dodefine(DB_RDONLY);

cxx/Makefile

 CPPFLAGS = -I../include
 CC = c++
-test1: test1.o dbt.o db.o
+LDFLAGS = -lz
+test1: test1.o dbt.o db.o dbenv.o ../lib/libdb.a
 

cxx/db.cpp

+#include <assert.h>
+#include <db.h>
+#include <errno.h>
 #include "db_cxx.h"
 
+Db::Db(DbEnv *env, u_int32_t flags) {
+    the_db   = 0;
+    the_Env = env;
+    if (the_Env == 0) {
+	is_private_env = 1;
+    }
+    DB *tmp_db;
+    int ret = db_create(&tmp_db, the_Env->get_DB_ENV(), flags & !(DB_CXX_NO_EXCEPTIONS));
+    if (ret!=0) {
+	assert(0); // make an error
+    }
+    the_db = tmp_db; 
+    tmp_db->api_internal = this;
+    if (is_private_env) {
+	the_Env = new DbEnv(tmp_db->dbenv, flags & DB_CXX_NO_EXCEPTIONS);
+    }
+}
+
 Db::~Db() {
     if (!the_db) {
 	close(0); // the user should have called close, but we do it here if not done.
@@ -10,13 +31,24 @@ int Db::close (u_int32_t flags) {
     if (!the_db) {
 	return EINVAL;
     }
-    the_db->toku_internal = 0;
+    the_db->api_internal = 0;
 
-    int ret = the_db->close(flags);
+    int ret = the_db->close(the_db, flags);
 
     the_db = 0;
     // Do we need to clean up "private environments"?
-    // What about cursors?  They should be cleaned up already.
+    // What about cursors?  They should be cleaned up already, but who did it?
+
+    return ret;
+}
+
+int Db::open(DbTxn *txn, const char *filename, const char *subname, DBTYPE typ, u_int32_t flags, int mode) {
+    int ret = the_db->open(the_db, txn->get_DB_TXN(), filename, subname, typ, flags, mode);
+    return ret;
+}
 
+int Db::put(DbTxn *txn, Dbt *key, Dbt *data, u_int32_t flags) {
+    int ret = the_db->put(the_db, txn->get_DB_TXN(), key->get_DBT(), data->get_DBT(), flags);
     return ret;
 }
+

cxx/db_cxx.h

@@ -2,6 +2,9 @@
 #include <string.h>
 
 class Dbt;
+class DbEnv;
+class DbTxn;
+class Dbc;
 
 // DBT and Dbt objects are the same pointers.  So watch out if you use Dbt to make other classes (e.g., with subclassing).
 class Dbt : private DBT
@@ -16,6 +19,7 @@ class Dbt : private DBT
 		       
     DBT *get_DBT(void)                 { return (DBT*)this; }
 
+    Dbt(void */*data*/, u_int32_t /*size*/);
     Dbt(void);
     ~Dbt();
 
@@ -29,17 +33,17 @@ class Db {
     Db(DbEnv *dbenv, u_int32_t flags);
     ~Db();
 
-    DB *Db::get_DB(void) {
+    DB *get_DB(void) {
 	return the_db;
     }
-    const DB *Db::get_const_DB() const {
+    const DB *get_const_DB() const {
 	return the_db;
     }
-    static Db *Db::get_Db(DB *db) {
-	return (Db*)db->toku_internal;
+    static Db *get_Db(DB *db) {
+	return (Db*)db->api_internal;
     }
-    static const Db *Db::get_const_Db(const DB *db) {
-	return (Db*)db->toku_internal;
+    static const Db *get_const_Db(const DB *db) {
+	return (Db*)db->api_internal;
     }
 
     /* C++ analogues of the C functions. */
@@ -55,5 +59,36 @@ class Db {
 
  private:
     DB *the_db;
+    DbEnv *the_Env;
+    int is_private_env;
+};
+
+class DbEnv {
+    friend class Db;
+ public:
+    DbEnv(u_int32_t flags);
+
+    DB_ENV *get_DB_ENV(void) {
+	return the_env;
+    }
+
+    /* C++ analogues of the C functions. */
+    int close(u_int32_t);
+
+ private:
+    DB_ENV *the_env;
+
+    DbEnv(DB_ENV *, u_int32_t flags);
+};
+
 	
+class DbTxn {
+ public:
+    DB_TXN *get_DB_TXN()
+	{
+	    return the_txn;
+	}
+ private:
+    DB_TXN *the_txn;
 };
+

cxx/dbt.cpp

@@ -5,6 +5,13 @@ Dbt::Dbt(void) {
     memset(dbt, 0, sizeof(*dbt));
 }
 
+Dbt::Dbt(void *data, u_int32_t size) {
+    DBT *dbt = this;
+    memset(dbt, 0, sizeof(*dbt));
+    set_data(data);
+    set_size(size);
+}
+
 Dbt::~Dbt(void)
 {
 }

cxx/tests/Makefile

+SRCS = $(wildcard *.cpp)
+TARGETS = $(patsubst %.cpp,%,$(SRCS))
+
+DBCXX = ../dbt.o ../db.o ../dbenv.o ../dbt.o
+CPPFLAGS = -I../ -I../../include
+CXXFLAGS = -Wall -g
+LDFLAGS = -L../lib -ldb
+
+$(TARGETS): $(DBCXX)
+
+all: $(TARGETS)
+
+clean:
+	rm -rf $(TARGETS)

cxx/tests/db_create.cpp

+#include <assert.h>
+#include <db_cxx.h>
+
+int dbcreate(char *dbfile, char *dbname, int argc, char *argv[]) {
+    int r;
+#if USE_ENV
+    DbEnv *env = new DbEnv(DB_CXX_NO_EXCEPTIONS);
+    r = env->open(".", DB_INIT_MPOOL + DB_CREATE + DB_PRIVATE, 0777); assert(r == 0);
+#else
+    DbEnv *env = 0;
+#endif
+    Db *db = new Db(env, DB_CXX_NO_EXCEPTIONS);
+    r = db->open(0, dbfile, dbname, DB_BTREE, DB_CREATE, 0777);
+    assert(r == 0);
+
+    int i = 0;
+    while (i < argc) {
+        char *k = argv[i++];
+        if (i < argc) {
+            char *v = argv[i++];
+            Dbt key(k, strlen(k)); Dbt val(v, strlen(v));
+            r = db->put(0, &key, &val, 0); assert(r == 0);
+        }
+    }
+            
+    r = db->close(0); assert(r == 0);
+    if (env) {
+        r = env->close(0); assert(r == 0);
+        delete env;
+    }
+    return 0;
+}
+
+int usage() {
+    printf("db_create [-s DBNAME] DBFILE [KEY VAL]*\n");
+    return 1;
+}
+
+int main(int argc, char *argv[]) {
+    char *dbname = 0;
+
+    int i;
+    for (i=1; i<argc; i++) {
+        char *arg = argv[i];
+        if (0 == strcmp(arg, "-h") || 0 == strcmp(arg, "--help"))
+            return usage();
+        if (0 == strcmp(arg, "-s")) {
+            i++;
+            if (i >= argc)
+                return usage();
+            dbname = argv[i];
+            continue;
+        }
+        break;
+    }
+
+    if (i >= argc)
+        return usage();
+    char *dbfile = argv[i++];
+    return dbcreate(dbfile, dbname, argc-i, &argv[i]);
+}
+

include/db.h

@@ -43,6 +43,7 @@ typedef enum {
 #define DB_ARCH_ABS 1
 #define DB_ARCH_LOG 4
 #define DB_CREATE 1
+#define DB_CXX_NO_EXCEPTIONS 1
 #define DB_EXCL 8192
 #define DB_PRIVATE 1048576
 #define DB_RDONLY 16