refactored PD framework, now using new sigrok.Decoder object

This uses the new python unified type/class object API to construct
an object for PDs to subclass. The sigrok.Decoder class has a method
put() which is implemented as a C function, and receives the PD's
object instance as its first parameter.

1 files changed, 74 insertions, 0 deletions

diff --git a/util.c b/util.c
new file mode 100644
index 0000000..3aa0fd9
--- /dev/null
+++ b/util.c
@@ -0,0 +1,74 @@
+/*
+ * This file is part of the sigrok project.
+ *
+ * Copyright (C) 2010 Uwe Hermann <uwe@hermann-uwe.de>
+ * Copyright (C) 2011 Bert Vermeulen <bert@biot.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+#include <sigrokdecode.h> /* First, so we avoid a _POSIX_C_SOURCE warning. */
+
+
+/**
+ * Helper function to handle Python strings.
+ *
+ * TODO: @param entries.
+ *
+ * @return SRD_OK upon success, a (negative) error code otherwise.
+ *         The 'outstr' argument points to a malloc()ed string upon success.
+ */
+int h_str(PyObject *py_res, PyObject *py_mod, const char *key, char **outstr)
+{
+	PyObject *py_str;
+	char *str;
+	int ret;
+
+	py_str = PyObject_GetAttrString(py_res, (char *)key); /* NEWREF */
+	if (!py_str || !PyString_Check(py_str)) {
+		ret = SRD_ERR_PYTHON; /* TODO: More specific error? */
+		goto err_h_decref_mod;
+	}
+
+	/*
+	 * PyString_AsString()'s returned string refers to an internal buffer
+	 * (not a copy), i.e. the data must not be modified, and the memory
+	 * must not be free()'d.
+	 */
+	if (!(str = PyString_AsString(py_str))) {
+		ret = SRD_ERR_PYTHON; /* TODO: More specific error? */
+		goto err_h_decref_str;
+	}
+
+	if (!(*outstr = g_strdup(str))) {
+		ret = SRD_ERR_MALLOC;
+		goto err_h_decref_str;
+	}
+
+	Py_XDECREF(py_str);
+
+	return SRD_OK;
+
+err_h_decref_str:
+	Py_XDECREF(py_str);
+err_h_decref_mod:
+	Py_XDECREF(py_mod);
+
+	if (PyErr_Occurred())
+		PyErr_Print(); /* Returns void. */
+
+	return ret;
+}
+