#include <stdio.h>
#include <string.h>
#include <dirent.h>
+#include <config.h>
/* Re-define some string functions for Python >= 3.0. */
#if PY_VERSION_HEX >= 0x03000000
/* The list of protocol decoders. */
GSList *list_pds = NULL;
+/*
+ * Here's a quick overview of Python/C API reference counting.
+ *
+ * Check the Python/C API docs for what type of reference a function returns.
+ *
+ * - If it returns a "new reference", you're responsible to Py_XDECREF() it.
+ *
+ * - If it returns a "borrowed reference", you MUST NOT Py_XDECREF() it.
+ *
+ * - If a function "steals" a reference, you no longer are responsible for
+ * Py_XDECREF()ing it (someone else will do it for you at some point).
+ */
+
/**
* Initialize libsigrokdecode.
*
/* Py_Initialize() returns void and usually cannot fail. */
Py_Initialize();
- /* Add some more search directories for convenience. */
+ /* Add search directory for the protocol decoders. */
/* FIXME: Check error code. */
/* FIXME: What happens if this function is called multiple times? */
- PyRun_SimpleString(
- "import sys;"
- "sys.path.append('libsigrokdecode/decoders');"
- "sys.path.append('" DECODERS_DIR "');"
- );
+ PyRun_SimpleString("import sys;"
+ "sys.path.append(r'" DECODERS_DIR "');");
if (!(dir = opendir(DECODERS_DIR)))
return SIGROKDECODE_ERR_DECODERS_DIR;
while ((dp = readdir(dir)) != NULL) {
- if (!strstr(dp->d_name, ".py"))
+ if (!g_str_has_suffix(dp->d_name, ".py"))
continue;
- if ((tmp = strdup(dp->d_name)))
+ /* For now use the filename (without .py) as decoder name. */
+ if ((tmp = g_strndup(dp->d_name, strlen(dp->d_name) - 3)))
list_pds = g_slist_append(list_pds, tmp);
}
closedir(dir);
*
* TODO: @param entries.
*
- * @return LIBSIGROKDECODE_OK upon success, a (negative) error code otherwise.
+ * @return SIGROKDECODE_OK upon success, a (negative) error code otherwise.
* The 'outstr' argument points to a malloc()ed string upon success.
*/
static int h_str(PyObject *py_res, PyObject *py_func, PyObject *py_mod,
{
PyObject *py_str;
char *str;
+ int ret;
py_str = PyMapping_GetItemString(py_res, (char *)key);
if (!py_str || !PyString_Check(py_str)) {
- if (PyErr_Occurred())
- PyErr_Print();
- Py_DECREF(py_func);
- Py_DECREF(py_mod);
- return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
+ ret = SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
+ goto err_h_decref_func;
}
+ /*
+ * 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))) {
- if (PyErr_Occurred())
- PyErr_Print();
- Py_DECREF(py_str);
- Py_DECREF(py_func);
- Py_DECREF(py_mod);
- return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
+ ret = SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
+ goto err_h_decref_str;
}
if (!(*outstr = strdup(str))) {
- if (PyErr_Occurred())
- PyErr_Print();
- Py_DECREF(py_str);
- Py_DECREF(py_func);
- Py_DECREF(py_mod);
- return SIGROKDECODE_ERR_MALLOC;
+ ret = SIGROKDECODE_ERR_MALLOC;
+ goto err_h_decref_str;
}
- Py_DECREF(py_str);
+ Py_XDECREF(py_str);
return SIGROKDECODE_OK;
+
+err_h_decref_str:
+ Py_XDECREF(py_str);
+err_h_decref_func:
+ Py_XDECREF(py_func);
+err_h_decref_mod:
+ Py_XDECREF(py_mod);
+
+ if (PyErr_Occurred())
+ PyErr_Print(); /* Returns void. */
+
+ return ret;
}
/**
*
* @param name TODO
*
- * @return LIBSIGROKDECODE_OK upon success, a (negative) error code otherwise.
+ * @return SIGROKDECODE_OK upon success, a (negative) error code otherwise.
*/
int sigrokdecode_load_decoder(const char *name,
struct sigrokdecode_decoder **dec)
{
struct sigrokdecode_decoder *d;
- PyObject *py_name, *py_mod, *py_func, *py_res /* , *py_tuple */;
+ PyObject *py_mod, *py_func, *py_res /* , *py_tuple */;
int r;
- /* Get the name of the decoder module as Python string. */
- if (!(py_name = PyString_FromString(name))) {
- PyErr_Print();
- return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
- }
-
/* "Import" the Python module. */
- if (!(py_mod = PyImport_Import(py_name))) {
- PyErr_Print();
- Py_DECREF(py_name);
+ if (!(py_mod = PyImport_ImportModule(name))) { /* NEWREF */
+ PyErr_Print(); /* Returns void. */
return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
}
- Py_DECREF(py_name);
/* Get the 'register' function name as Python callable object. */
- py_func = PyObject_GetAttrString(py_mod, "register");
+ py_func = PyObject_GetAttrString(py_mod, "register"); /* NEWREF */
if (!py_func || !PyCallable_Check(py_func)) {
if (PyErr_Occurred())
- PyErr_Print();
- Py_DECREF(py_mod);
+ PyErr_Print(); /* Returns void. */
+ Py_XDECREF(py_mod);
return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
}
/* Call the 'register' function without arguments, get the result. */
- if (!(py_res = PyObject_CallFunction(py_func, NULL))) {
- PyErr_Print();
- Py_DECREF(py_func);
- Py_DECREF(py_mod);
+ if (!(py_res = PyObject_CallFunction(py_func, NULL))) { /* NEWREF */
+ PyErr_Print(); /* Returns void. */
+ Py_XDECREF(py_func);
+ Py_XDECREF(py_mod);
return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
}
d->py_mod = py_mod;
- Py_DECREF(py_res);
- Py_DECREF(py_func);
+ Py_XDECREF(py_res);
+ Py_XDECREF(py_func);
/* Get the 'decode' function name as Python callable object. */
- py_func = PyObject_GetAttrString(py_mod, "decode");
+ py_func = PyObject_GetAttrString(py_mod, "decode"); /* NEWREF */
if (!py_func || !PyCallable_Check(py_func)) {
if (PyErr_Occurred())
- PyErr_Print();
- Py_DECREF(py_mod);
+ PyErr_Print(); /* Returns void. */
+ Py_XDECREF(py_mod);
return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
}
* @param outbuf TODO
* @param outbuflen TODO
*
- * @return LIBSIGROKDECODE_OK upon success, a (negative) error code otherwise.
+ * @return SIGROKDECODE_OK upon success, a (negative) error code otherwise.
*/
int sigrokdecode_run_decoder(struct sigrokdecode_decoder *dec,
uint8_t *inbuf, uint64_t inbuflen,
uint8_t **outbuf, uint64_t *outbuflen)
{
PyObject *py_mod, *py_func, *py_args, *py_value, *py_res;
- int ret;
+ int r, ret;
/* TODO: Use #defines for the return codes. */
/* TODO: Error handling. */
py_mod = dec->py_mod;
+ Py_XINCREF(py_mod);
py_func = dec->py_func;
-
- /* TODO: Really run Py_DECREF on py_mod/py_func? */
+ Py_XINCREF(py_func);
/* Create a Python tuple of size 1. */
- if (!(py_args = PyTuple_New(1))) {
- PyErr_Print();
- Py_DECREF(py_func);
- Py_DECREF(py_mod);
- return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
+ if (!(py_args = PyTuple_New(1))) { /* NEWREF */
+ ret = SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
+ goto err_run_decref_func;
}
/* Get the input buffer as Python "string" (byte array). */
/* TODO: int vs. uint64_t for 'inbuflen'? */
- if (!(py_value = Py_BuildValue("s#", inbuf, inbuflen))) {
- PyErr_Print();
- Py_DECREF(py_args);
- Py_DECREF(py_func);
- Py_DECREF(py_mod);
- return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
+ if (!(py_value = Py_BuildValue("s#", inbuf, inbuflen))) { /* NEWREF */
+ ret = SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
+ goto err_run_decref_args;
}
- if (PyTuple_SetItem(py_args, 0, py_value) != 0) {
- PyErr_Print();
- Py_DECREF(py_value);
- Py_DECREF(py_args);
- Py_DECREF(py_func);
- Py_DECREF(py_mod);
- return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
+ /*
+ * IMPORTANT: PyTuple_SetItem() "steals" a reference to py_value!
+ * That means we are no longer responsible for Py_XDECREF()'ing it.
+ * It will automatically be free'd when the 'py_args' tuple is free'd.
+ */
+ if (PyTuple_SetItem(py_args, 0, py_value) != 0) { /* STEAL */
+ ret = SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
+ Py_XDECREF(py_value); /* TODO: Ref. stolen upon error? */
+ goto err_run_decref_args;
}
- if (!(py_res = PyObject_CallObject(py_func, py_args))) {
- PyErr_Print();
- Py_DECREF(py_value);
- Py_DECREF(py_args);
- Py_DECREF(py_func);
- Py_DECREF(py_mod);
- return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
+ if (!(py_res = PyObject_CallObject(py_func, py_args))) { /* NEWREF */
+ ret = SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
+ goto err_run_decref_args;
}
- if ((ret = PyObject_AsCharBuffer(py_res, (const char **)outbuf,
- (Py_ssize_t *)outbuflen))) {
- PyErr_Print();
- Py_DECREF(py_res);
- Py_DECREF(py_value);
- Py_DECREF(py_args);
- Py_DECREF(py_func);
- Py_DECREF(py_mod);
- return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
+ if ((r = PyObject_AsCharBuffer(py_res, (const char **)outbuf,
+ (Py_ssize_t *)outbuflen))) {
+ ret = SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
+ Py_XDECREF(py_res);
+ goto err_run_decref_args;
}
- Py_DECREF(py_res);
- // Py_DECREF(py_value);
- Py_DECREF(py_args);
- Py_DECREF(py_func);
- Py_DECREF(py_mod);
+ ret = SIGROKDECODE_OK;
- return SIGROKDECODE_OK;
+ Py_XDECREF(py_res);
+
+err_run_decref_args:
+ Py_XDECREF(py_args);
+err_run_decref_func:
+ Py_XDECREF(py_func);
+err_run_decref_mod:
+ Py_XDECREF(py_mod);
+
+ if (PyErr_Occurred())
+ PyErr_Print(); /* Returns void. */
+
+ return ret;
}
/**
* Shutdown libsigrokdecode.
*
- * @return LIBSIGROKDECODE_OK upon success, a (negative) error code otherwise.
+ * @return SIGROKDECODE_OK upon success, a (negative) error code otherwise.
*/
int sigrokdecode_shutdown(void)
{