Create the dbm package from PEP 3108. #2881.

1 files changed, 412 insertions, 0 deletions

diff --git a/Modules/_dbmmodule.c b/Modules/_dbmmodule.c
new file mode 100644
index 0000000..1a49e24
--- /dev/null
+++ b/Modules/_dbmmodule.c
@@ -0,0 +1,412 @@
+
+/* DBM module using dictionary interface */
+
+
+#include "Python.h"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+/* Some Linux systems install gdbm/ndbm.h, but not ndbm.h.  This supports
+ * whichever configure was able to locate.
+ */
+#if defined(HAVE_NDBM_H)
+#include <ndbm.h>
+#if defined(PYOS_OS2) && !defined(PYCC_GCC)
+static char *which_dbm = "ndbm";
+#else
+static char *which_dbm = "GNU gdbm";  /* EMX port of GDBM */
+#endif
+#elif defined(HAVE_GDBM_NDBM_H)
+#include <gdbm/ndbm.h>
+static char *which_dbm = "GNU gdbm";
+#elif defined(HAVE_BERKDB_H)
+#include <db.h>
+static char *which_dbm = "Berkeley DB";
+#else
+#error "No ndbm.h available!"
+#endif
+
+typedef struct {
+	PyObject_HEAD
+	int di_size;	/* -1 means recompute */
+	DBM *di_dbm;
+} dbmobject;
+
+static PyTypeObject Dbmtype;
+
+#define is_dbmobject(v) (Py_TYPE(v) == &Dbmtype)
+#define check_dbmobject_open(v) if ((v)->di_dbm == NULL) \
+               { PyErr_SetString(DbmError, "DBM object has already been closed"); \
+                 return NULL; }
+
+static PyObject *DbmError;
+
+static PyObject *
+newdbmobject(char *file, int flags, int mode)
+{
+        dbmobject *dp;
+
+	dp = PyObject_New(dbmobject, &Dbmtype);
+	if (dp == NULL)
+		return NULL;
+	dp->di_size = -1;
+	if ( (dp->di_dbm = dbm_open(file, flags, mode)) == 0 ) {
+		PyErr_SetFromErrno(DbmError);
+		Py_DECREF(dp);
+		return NULL;
+	}
+	return (PyObject *)dp;
+}
+
+/* Methods */
+
+static void
+dbm_dealloc(register dbmobject *dp)
+{
+        if ( dp->di_dbm )
+		dbm_close(dp->di_dbm);
+	PyObject_Del(dp);
+}
+
+static Py_ssize_t
+dbm_length(dbmobject *dp)
+{
+        if (dp->di_dbm == NULL) {
+                 PyErr_SetString(DbmError, "DBM object has already been closed"); 
+                 return -1; 
+        }
+        if ( dp->di_size < 0 ) {
+		datum key;
+		int size;
+
+		size = 0;
+		for ( key=dbm_firstkey(dp->di_dbm); key.dptr;
+		      key = dbm_nextkey(dp->di_dbm))
+			size++;
+		dp->di_size = size;
+	}
+	return dp->di_size;
+}
+
+static PyObject *
+dbm_subscript(dbmobject *dp, register PyObject *key)
+{
+	datum drec, krec;
+	Py_ssize_t tmp_size;
+	
+	if (!PyArg_Parse(key, "s#", &krec.dptr, &tmp_size) )
+		return NULL;
+	
+	krec.dsize = tmp_size;
+        check_dbmobject_open(dp);
+	drec = dbm_fetch(dp->di_dbm, krec);
+	if ( drec.dptr == 0 ) {
+		PyErr_SetObject(PyExc_KeyError, key);
+		return NULL;
+	}
+	if ( dbm_error(dp->di_dbm) ) {
+		dbm_clearerr(dp->di_dbm);
+		PyErr_SetString(DbmError, "");
+		return NULL;
+	}
+	return PyBytes_FromStringAndSize(drec.dptr, drec.dsize);
+}
+
+static int
+dbm_ass_sub(dbmobject *dp, PyObject *v, PyObject *w)
+{
+        datum krec, drec;
+	Py_ssize_t tmp_size;
+	
+        if ( !PyArg_Parse(v, "s#", &krec.dptr, &tmp_size) ) {
+		PyErr_SetString(PyExc_TypeError,
+				"dbm mappings have string keys only");
+		return -1;
+	}
+	krec.dsize = tmp_size;
+        if (dp->di_dbm == NULL) {
+                 PyErr_SetString(DbmError, "DBM object has already been closed"); 
+                 return -1;
+        }
+	dp->di_size = -1;
+	if (w == NULL) {
+		if ( dbm_delete(dp->di_dbm, krec) < 0 ) {
+			dbm_clearerr(dp->di_dbm);
+			PyErr_SetObject(PyExc_KeyError, v);
+			return -1;
+		}
+	} else {
+		if ( !PyArg_Parse(w, "s#", &drec.dptr, &tmp_size) ) {
+			PyErr_SetString(PyExc_TypeError,
+			     "dbm mappings have byte string elements only");
+			return -1;
+		}
+		drec.dsize = tmp_size;
+		if ( dbm_store(dp->di_dbm, krec, drec, DBM_REPLACE) < 0 ) {
+			dbm_clearerr(dp->di_dbm);
+			PyErr_SetString(DbmError,
+					"cannot add item to database");
+			return -1;
+		}
+	}
+	if ( dbm_error(dp->di_dbm) ) {
+		dbm_clearerr(dp->di_dbm);
+		PyErr_SetString(DbmError, "");
+		return -1;
+	}
+	return 0;
+}
+
+static PyMappingMethods dbm_as_mapping = {
+	(lenfunc)dbm_length,		/*mp_length*/
+	(binaryfunc)dbm_subscript,	/*mp_subscript*/
+	(objobjargproc)dbm_ass_sub,	/*mp_ass_subscript*/
+};
+
+static PyObject *
+dbm__close(register dbmobject *dp, PyObject *unused)
+{
+        if (dp->di_dbm)
+		dbm_close(dp->di_dbm);
+	dp->di_dbm = NULL;
+	Py_INCREF(Py_None);
+	return Py_None;
+}
+
+static PyObject *
+dbm_keys(register dbmobject *dp, PyObject *unused)
+{
+	register PyObject *v, *item;
+	datum key;
+	int err;
+
+        check_dbmobject_open(dp);
+	v = PyList_New(0);
+	if (v == NULL)
+		return NULL;
+	for (key = dbm_firstkey(dp->di_dbm); key.dptr;
+	     key = dbm_nextkey(dp->di_dbm)) {
+		item = PyBytes_FromStringAndSize(key.dptr, key.dsize);
+		if (item == NULL) {
+			Py_DECREF(v);
+			return NULL;
+		}
+		err = PyList_Append(v, item);
+		Py_DECREF(item);
+		if (err != 0) {
+			Py_DECREF(v);
+			return NULL;
+		}
+	}
+	return v;
+}
+
+static int
+dbm_contains(PyObject *self, PyObject *arg)
+{
+	dbmobject *dp = (dbmobject *)self;
+	datum key, val;
+
+	if ((dp)->di_dbm == NULL) {
+		PyErr_SetString(DbmError,
+				"DBM object has already been closed");
+                 return -1;
+	}
+	if (PyUnicode_Check(arg)) {
+		arg = _PyUnicode_AsDefaultEncodedString(arg, NULL);
+		if (arg == NULL)
+			return -1;
+	}
+	if (!PyString_Check(arg)) {
+		PyErr_Format(PyExc_TypeError,
+			     "dbm key must be string, not %.100s",
+			     arg->ob_type->tp_name);
+		return -1;
+	}
+	key.dptr = PyString_AS_STRING(arg);
+	key.dsize = PyString_GET_SIZE(arg);
+	val = dbm_fetch(dp->di_dbm, key);
+	return val.dptr != NULL;
+}
+
+static PySequenceMethods dbm_as_sequence = {
+	0,			/* sq_length */
+	0,			/* sq_concat */
+	0,			/* sq_repeat */
+	0,			/* sq_item */
+	0,			/* sq_slice */
+	0,			/* sq_ass_item */
+	0,			/* sq_ass_slice */
+	dbm_contains,		/* sq_contains */
+	0,			/* sq_inplace_concat */
+	0,			/* sq_inplace_repeat */
+};
+
+static PyObject *
+dbm_get(register dbmobject *dp, PyObject *args)
+{
+	datum key, val;
+	PyObject *defvalue = Py_None;
+	char *tmp_ptr;
+	Py_ssize_t tmp_size;
+
+	if (!PyArg_ParseTuple(args, "s#|O:get",
+                              &tmp_ptr, &tmp_size, &defvalue))
+		return NULL;
+	key.dptr = tmp_ptr;
+	key.dsize = tmp_size;
+        check_dbmobject_open(dp);
+	val = dbm_fetch(dp->di_dbm, key);
+	if (val.dptr != NULL)
+		return PyBytes_FromStringAndSize(val.dptr, val.dsize);
+	else {
+		Py_INCREF(defvalue);
+		return defvalue;
+	}
+}
+
+static PyObject *
+dbm_setdefault(register dbmobject *dp, PyObject *args)
+{
+	datum key, val;
+	PyObject *defvalue = NULL;
+	char *tmp_ptr;
+	Py_ssize_t tmp_size;
+
+	if (!PyArg_ParseTuple(args, "s#|O:setdefault",
+                              &tmp_ptr, &tmp_size, &defvalue))
+		return NULL;
+	key.dptr = tmp_ptr;
+	key.dsize = tmp_size;
+        check_dbmobject_open(dp);
+	val = dbm_fetch(dp->di_dbm, key);
+	if (val.dptr != NULL)
+		return PyBytes_FromStringAndSize(val.dptr, val.dsize);
+	if (defvalue == NULL) {
+		defvalue = PyBytes_FromStringAndSize(NULL, 0);
+		if (defvalue == NULL)
+			return NULL;
+		val.dptr = NULL;
+		val.dsize = 0;
+	}
+	else {
+		if ( !PyArg_Parse(defvalue, "s#", &val.dptr, &tmp_size) ) {
+			PyErr_SetString(PyExc_TypeError,
+				"dbm mappings have byte string elements only");
+			return NULL;
+		}
+		val.dsize = tmp_size;
+		Py_INCREF(defvalue);
+	}
+	if (dbm_store(dp->di_dbm, key, val, DBM_INSERT) < 0) {
+		dbm_clearerr(dp->di_dbm);
+		PyErr_SetString(DbmError, "cannot add item to database");
+		Py_DECREF(defvalue);
+		return NULL;
+	}
+	return defvalue;
+}
+
+static PyMethodDef dbm_methods[] = {
+	{"close",	(PyCFunction)dbm__close,	METH_NOARGS,
+	 "close()\nClose the database."},
+	{"keys",	(PyCFunction)dbm_keys,		METH_NOARGS,
+	 "keys() -> list\nReturn a list of all keys in the database."},
+	{"get",		(PyCFunction)dbm_get,		METH_VARARGS,
+	 "get(key[, default]) -> value\n"
+	 "Return the value for key if present, otherwise default."},
+	{"setdefault",	(PyCFunction)dbm_setdefault,	METH_VARARGS,
+	 "setdefault(key[, default]) -> value\n"
+	 "Return the value for key if present, otherwise default.  If key\n"
+	 "is not in the database, it is inserted with default as the value."},
+	{NULL,		NULL}		/* sentinel */
+};
+
+static PyObject *
+dbm_getattr(dbmobject *dp, char *name)
+{
+	return Py_FindMethod(dbm_methods, (PyObject *)dp, name);
+}
+
+static PyTypeObject Dbmtype = {
+	PyVarObject_HEAD_INIT(NULL, 0)
+	"_dbm.dbm",
+	sizeof(dbmobject),
+	0,
+	(destructor)dbm_dealloc,  /*tp_dealloc*/
+	0,			  /*tp_print*/
+	(getattrfunc)dbm_getattr, /*tp_getattr*/
+	0,			  /*tp_setattr*/
+	0,			  /*tp_compare*/
+	0,			  /*tp_repr*/
+	0,			  /*tp_as_number*/
+	&dbm_as_sequence,	  /*tp_as_sequence*/
+	&dbm_as_mapping,	  /*tp_as_mapping*/
+	0,                    /*tp_hash*/
+	0,                    /*tp_call*/
+	0,                    /*tp_str*/
+	0,                    /*tp_getattro*/
+	0,                    /*tp_setattro*/
+	0,                    /*tp_as_buffer*/
+	Py_TPFLAGS_DEFAULT,   /*tp_xxx4*/
+};
+
+/* ----------------------------------------------------------------- */
+
+static PyObject *
+dbmopen(PyObject *self, PyObject *args)
+{
+	char *name;
+	char *flags = "r";
+	int iflags;
+	int mode = 0666;
+
+        if ( !PyArg_ParseTuple(args, "s|si:open", &name, &flags, &mode) )
+		return NULL;
+	if ( strcmp(flags, "r") == 0 )
+		iflags = O_RDONLY;
+	else if ( strcmp(flags, "w") == 0 )
+		iflags = O_RDWR;
+	else if ( strcmp(flags, "rw") == 0 ) /* B/W compat */
+		iflags = O_RDWR|O_CREAT; 
+	else if ( strcmp(flags, "c") == 0 )
+		iflags = O_RDWR|O_CREAT;
+	else if ( strcmp(flags, "n") == 0 )
+		iflags = O_RDWR|O_CREAT|O_TRUNC;
+	else {
+		PyErr_SetString(DbmError,
+				"arg 2 to open should be 'r', 'w', 'c', or 'n'");
+		return NULL;
+	}
+        return newdbmobject(name, iflags, mode);
+}
+
+static PyMethodDef dbmmodule_methods[] = {
+	{ "open", (PyCFunction)dbmopen, METH_VARARGS,
+	  "open(path[, flag[, mode]]) -> mapping\n"
+	  "Return a database object."},
+	{ 0, 0 },
+};
+
+PyMODINIT_FUNC
+init_dbm(void) {
+	PyObject *m, *d, *s;
+
+	if (PyType_Ready(&Dbmtype) < 0)
+		return;
+	m = Py_InitModule("_dbm", dbmmodule_methods);
+	if (m == NULL)
+		return;
+	d = PyModule_GetDict(m);
+	if (DbmError == NULL)
+		DbmError = PyErr_NewException("_dbm.error", NULL, NULL);
+	s = PyUnicode_FromString(which_dbm);
+	if (s != NULL) {
+		PyDict_SetItemString(d, "library", s);
+		Py_DECREF(s);
+	}
+	if (DbmError != NULL)
+		PyDict_SetItemString(d, "error", DbmError);
+}