[libsigrokdecode.git] / decode.c

/*
 * This file is part of the sigrok project.
 *
 * Copyright (C) 2010 Uwe Hermann <uwe@hermann-uwe.de>
 *
 * 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 2 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, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 */

#include "config.h"
#include <sigrokdecode.h> /* First, so we avoid a _POSIX_C_SOURCE warning. */
#include <stdio.h>
#include <string.h>
#include <dirent.h>

/* Re-define some string functions for Python >= 3.0. */
#if PY_VERSION_HEX >= 0x03000000
#define PyString_AsString PyBytes_AsString
#define PyString_FromString PyBytes_FromString
#define PyString_Check PyBytes_Check
#endif

/* 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).
 */

static int srd_load_decoder(const char *name, struct srd_decoder **dec);

/**
 * Initialize libsigrokdecode.
 *
 * @return SRD_OK upon success, a (negative) error code otherwise.
 */
int srd_init(void)
{
	DIR *dir;
	struct dirent *dp;
	char *decodername;
	struct srd_decoder *dec;
	int ret;

	/* Py_Initialize() returns void and usually cannot fail. */
	Py_Initialize();

	/* 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(r'" DECODERS_DIR "');");

	if (!(dir = opendir(DECODERS_DIR)))
		return SRD_ERR_DECODERS_DIR;

	while ((dp = readdir(dir)) != NULL) {
		if (!g_str_has_suffix(dp->d_name, ".py"))
			continue;

		/* Decoder name == filename (without .py suffix). */
		decodername = g_strndup(dp->d_name, strlen(dp->d_name) - 3);

		/* TODO: Error handling. */
		dec = malloc(sizeof(struct srd_decoder));

		/* Load the decoder. */
		ret = srd_load_decoder(decodername, &dec);

		/* Append it to the list of supported/loaded decoders. */
		list_pds = g_slist_append(list_pds, dec);
	}
	closedir(dir);

	return SRD_OK;
}

/**
 * Returns the list of supported/loaded protocol decoders.
 *
 * This is a GSList containing the names of the decoders as strings.
 *
 * @return List of decoders, NULL if none are supported or loaded.
 */
GSList *srd_list_decoders(void)
{
	return list_pds;
}

/**
 * Get the decoder with the specified ID.
 *
 * @param id The ID string of the decoder to return.
 * @return The decoder with the specified ID, or NULL if not found.
 */
struct srd_decoder *srd_get_decoder_by_id(const char *id)
{
	GSList *l;
	struct srd_decoder *dec;

	for (l = srd_list_decoders(); l; l = l->next) {
		dec = l->data;
		if (!strcmp(dec->id, id))
			return dec;
	}

	return NULL;
}

/**
 * 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.
 */
static int h_str(PyObject *py_res, PyObject *py_func, PyObject *py_mod,
		 const char *key, char **outstr)
{
	PyObject *py_str;
	char *str;
	int ret;

	py_str = PyMapping_GetItemString(py_res, (char *)key);
	if (!py_str || !PyString_Check(py_str)) {
		ret = SRD_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))) {
		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_func:
	Py_XDECREF(py_func);
	Py_XDECREF(py_mod);

	if (PyErr_Occurred())
		PyErr_Print(); /* Returns void. */

	return ret;
}

/**
 * TODO
 *
 * @param name TODO
 *
 * @return SRD_OK upon success, a (negative) error code otherwise.
 */
static int srd_load_decoder(const char *name,
			      struct srd_decoder **dec)
{
	struct srd_decoder *d;
	PyObject *py_mod, *py_func, *py_res /* , *py_tuple */;
	int r;

	/* "Import" the Python module. */
	if (!(py_mod = PyImport_ImportModule(name))) { /* NEWREF */
		PyErr_Print(); /* Returns void. */
		return SRD_ERR_PYTHON; /* TODO: More specific error? */
	}

	/* Get the 'register' function name as Python callable object. */
	py_func = PyObject_GetAttrString(py_mod, "register"); /* NEWREF */
	if (!py_func || !PyCallable_Check(py_func)) {
		if (PyErr_Occurred())
			PyErr_Print(); /* Returns void. */
		Py_XDECREF(py_mod);
		return SRD_ERR_PYTHON; /* TODO: More specific error? */
	}

	/* Call the 'register' function without arguments, get the result. */
	if (!(py_res = PyObject_CallFunction(py_func, NULL))) { /* NEWREF */
		PyErr_Print(); /* Returns void. */
		Py_XDECREF(py_func);
		Py_XDECREF(py_mod);
		return SRD_ERR_PYTHON; /* TODO: More specific error? */
	}

	if (!(d = malloc(sizeof(struct srd_decoder))))
		return SRD_ERR_MALLOC;

	if ((r = h_str(py_res, py_func, py_mod, "id", &(d->id))) < 0)
		return r;

	if ((r = h_str(py_res, py_func, py_mod, "name", &(d->name))) < 0)
		return r;

	if ((r = h_str(py_res, py_func, py_mod, "longname",
		       &(d->longname))) < 0)
		return r;

	if ((r = h_str(py_res, py_func, py_mod, "desc", &(d->desc))) < 0)
		return r;

	if ((r = h_str(py_res, py_func, py_mod, "longdesc",
		       &(d->longdesc))) < 0)
		return r;

	if ((r = h_str(py_res, py_func, py_mod, "author", &(d->author))) < 0)
		return r;

	if ((r = h_str(py_res, py_func, py_mod, "email", &(d->email))) < 0)
		return r;

	if ((r = h_str(py_res, py_func, py_mod, "license", &(d->license))) < 0)
		return r;

	d->py_mod = py_mod;

	Py_XDECREF(py_res);
	Py_XDECREF(py_func);

	/* Get the 'decode' function name as Python callable object. */
	py_func = PyObject_GetAttrString(py_mod, "decode"); /* NEWREF */
	if (!py_func || !PyCallable_Check(py_func)) {
		if (PyErr_Occurred())
			PyErr_Print(); /* Returns void. */
		Py_XDECREF(py_mod);
		return SRD_ERR_PYTHON; /* TODO: More specific error? */
	}

	d->py_func = py_func;

	/* TODO: Handle func, inputformats, outputformats. */
	/* Note: They must at least be set to NULL, will segfault otherwise. */
	d->func = NULL;
	d->inputformats = NULL;
	d->outputformats = NULL;

	*dec = d;

	return SRD_OK;
}

/**
 * Run the specified decoder function.
 *
 * @param dec TODO
 * @param inbuf TODO
 * @param inbuflen TODO
 * @param outbuf TODO
 * @param outbuflen TODO
 *
 * @return SRD_OK upon success, a (negative) error code otherwise.
 */
int srd_run_decoder(struct srd_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 r, ret;

	/* TODO: Use #defines for the return codes. */

	/* Return an error upon unusable input. */
	if (dec == NULL)
		return SRD_ERR_ARGS; /* TODO: More specific error? */
	if (inbuf == NULL)
		return SRD_ERR_ARGS; /* TODO: More specific error? */
	if (inbuflen == 0) /* No point in working on empty buffers. */
		return SRD_ERR_ARGS; /* TODO: More specific error? */
	if (outbuf == NULL)
		return SRD_ERR_ARGS; /* TODO: More specific error? */
	if (outbuflen == NULL)
		return SRD_ERR_ARGS; /* TODO: More specific error? */

	/* TODO: Error handling. */
	py_mod = dec->py_mod;
	Py_XINCREF(py_mod);
	py_func = dec->py_func;
	Py_XINCREF(py_func);

	/* Create a Python tuple of size 1. */
	if (!(py_args = PyTuple_New(1))) { /* NEWREF */
		ret = SRD_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))) { /* NEWREF */
		ret = SRD_ERR_PYTHON; /* TODO: More specific error? */
		goto err_run_decref_args;
	}

	/*
	 * 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 = SRD_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))) { /* NEWREF */
		ret = SRD_ERR_PYTHON; /* TODO: More specific error? */
		goto err_run_decref_args;
	}

	if ((r = PyObject_AsCharBuffer(py_res, (const char **)outbuf,
				      (Py_ssize_t *)outbuflen))) {
		ret = SRD_ERR_PYTHON; /* TODO: More specific error? */
		Py_XDECREF(py_res);
		goto err_run_decref_args;
	}

	ret = SRD_OK;

	Py_XDECREF(py_res);

err_run_decref_args:
	Py_XDECREF(py_args);
err_run_decref_func:
	Py_XDECREF(py_func);
	Py_XDECREF(py_mod);

	if (PyErr_Occurred())
		PyErr_Print(); /* Returns void. */

	return ret;
}

/**
 * TODO
 */
static int srd_unload_decoder(struct srd_decoder *dec)
{
	g_free(dec->id);
	g_free(dec->name);
	g_free(dec->desc);
	g_free(dec->func);

	/* TODO: Free everything in inputformats and outputformats. */

	if (dec->inputformats != NULL)
		g_slist_free(dec->inputformats);
	if (dec->outputformats != NULL)
		g_slist_free(dec->outputformats);

	Py_XDECREF(dec->py_func);
	Py_XDECREF(dec->py_mod);

	return SRD_OK;
}

/**
 * TODO
 */
static int srd_unload_all_decoders(void)
{
	GSList *l;
	struct srd_decoder *dec;

	for (l = srd_list_decoders(); l; l = l->next) {
		dec = l->data;
		/* TODO: Error handling. */
		srd_unload_decoder(dec);
	}

	return SRD_OK;
}

/**
 * Shutdown libsigrokdecode.
 *
 * @return SRD_OK upon success, a (negative) error code otherwise.
 */
int srd_exit(void)
{
	/* Unload/free all decoders, and then the list of decoders itself. */
	/* TODO: Error handling. */
	srd_unload_all_decoders();
	g_slist_free(list_pds);

	/* Py_Finalize() returns void, any finalization errors are ignored. */
	Py_Finalize();

	return SRD_OK;
}
Commit	Line	Data
	1	/*
	2	* This file is part of the sigrok project.
	3	*
	4	* Copyright (C) 2010 Uwe Hermann <uwe@hermann-uwe.de>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	19	*/
	20
	21	#include "config.h"
	22	#include <sigrokdecode.h> /* First, so we avoid a _POSIX_C_SOURCE warning. */
	23	#include <stdio.h>
	24	#include <string.h>
	25	#include <dirent.h>
	26
	27	/* Re-define some string functions for Python >= 3.0. */
	28	#if PY_VERSION_HEX >= 0x03000000
	29	#define PyString_AsString PyBytes_AsString
	30	#define PyString_FromString PyBytes_FromString
	31	#define PyString_Check PyBytes_Check
	32	#endif
	33
	34	/* The list of protocol decoders. */
	35	GSList *list_pds = NULL;
	36
	37	/*
	38	* Here's a quick overview of Python/C API reference counting.
	39	*
	40	* Check the Python/C API docs for what type of reference a function returns.
	41	*
	42	* - If it returns a "new reference", you're responsible to Py_XDECREF() it.
	43	*
	44	* - If it returns a "borrowed reference", you MUST NOT Py_XDECREF() it.
	45	*
	46	* - If a function "steals" a reference, you no longer are responsible for
	47	* Py_XDECREF()ing it (someone else will do it for you at some point).
	48	*/
	49
	50	static int srd_load_decoder(const char name, struct srd_decoder *dec);
	51
	52	/**
	53	* Initialize libsigrokdecode.
	54	*
	55	* @return SRD_OK upon success, a (negative) error code otherwise.
	56	*/
	57	int srd_init(void)
	58	{
	59	DIR *dir;
	60	struct dirent *dp;
	61	char *decodername;
	62	struct srd_decoder *dec;
	63	int ret;
	64
	65	/* Py_Initialize() returns void and usually cannot fail. */
	66	Py_Initialize();
	67
	68	/* Add search directory for the protocol decoders. */
	69	/* FIXME: Check error code. */
	70	/* FIXME: What happens if this function is called multiple times? */
	71	PyRun_SimpleString("import sys;"
	72	"sys.path.append(r'" DECODERS_DIR "');");
	73
	74	if (!(dir = opendir(DECODERS_DIR)))
	75	return SRD_ERR_DECODERS_DIR;
	76
	77	while ((dp = readdir(dir)) != NULL) {
	78	if (!g_str_has_suffix(dp->d_name, ".py"))
	79	continue;
	80
	81	/* Decoder name == filename (without .py suffix). */
	82	decodername = g_strndup(dp->d_name, strlen(dp->d_name) - 3);
	83
	84	/* TODO: Error handling. */
	85	dec = malloc(sizeof(struct srd_decoder));
	86
	87	/* Load the decoder. */
	88	ret = srd_load_decoder(decodername, &dec);
	89
	90	/* Append it to the list of supported/loaded decoders. */
	91	list_pds = g_slist_append(list_pds, dec);
	92	}
	93	closedir(dir);
	94
	95	return SRD_OK;
	96	}
	97
	98	/**
	99	* Returns the list of supported/loaded protocol decoders.
	100	*
	101	* This is a GSList containing the names of the decoders as strings.
	102	*
	103	* @return List of decoders, NULL if none are supported or loaded.
	104	*/
	105	GSList *srd_list_decoders(void)
	106	{
	107	return list_pds;
	108	}
	109
	110	/**
	111	* Get the decoder with the specified ID.
	112	*
	113	* @param id The ID string of the decoder to return.
	114	* @return The decoder with the specified ID, or NULL if not found.
	115	*/
	116	struct srd_decoder srd_get_decoder_by_id(const char id)
	117	{
	118	GSList *l;
	119	struct srd_decoder *dec;
	120
	121	for (l = srd_list_decoders(); l; l = l->next) {
	122	dec = l->data;
	123	if (!strcmp(dec->id, id))
	124	return dec;
	125	}
	126
	127	return NULL;
	128	}
	129
	130	/**
	131	* Helper function to handle Python strings.
	132	*
	133	* TODO: @param entries.
	134	*
	135	* @return SRD_OK upon success, a (negative) error code otherwise.
	136	* The 'outstr' argument points to a malloc()ed string upon success.
	137	*/
	138	static int h_str(PyObject py_res, PyObject py_func, PyObject *py_mod,
	139	const char key, char *outstr)
	140	{
	141	PyObject *py_str;
	142	char *str;
	143	int ret;
	144
	145	py_str = PyMapping_GetItemString(py_res, (char *)key);
	146	if (!py_str \|\| !PyString_Check(py_str)) {
	147	ret = SRD_ERR_PYTHON; /* TODO: More specific error? */
	148	goto err_h_decref_func;
	149	}
	150
	151	/*
	152	* PyString_AsString()'s returned string refers to an internal buffer
	153	* (not a copy), i.e. the data must not be modified, and the memory
	154	* must not be free()'d.
	155	*/
	156	if (!(str = PyString_AsString(py_str))) {
	157	ret = SRD_ERR_PYTHON; /* TODO: More specific error? */
	158	goto err_h_decref_str;
	159	}
	160
	161	if (!(*outstr = g_strdup(str))) {
	162	ret = SRD_ERR_MALLOC;
	163	goto err_h_decref_str;
	164	}
	165
	166	Py_XDECREF(py_str);
	167
	168	return SRD_OK;
	169
	170	err_h_decref_str:
	171	Py_XDECREF(py_str);
	172	err_h_decref_func:
	173	Py_XDECREF(py_func);
	174	Py_XDECREF(py_mod);
	175
	176	if (PyErr_Occurred())
	177	PyErr_Print(); /* Returns void. */
	178
	179	return ret;
	180	}
	181
	182	/**
	183	* TODO
	184	*
	185	* @param name TODO
	186	*
	187	* @return SRD_OK upon success, a (negative) error code otherwise.
	188	*/
	189	static int srd_load_decoder(const char *name,
	190	struct srd_decoder **dec)
	191	{
	192	struct srd_decoder *d;
	193	PyObject py_mod, py_func, py_res / , py_tuple /;
	194	int r;
	195
	196	/* "Import" the Python module. */
	197	if (!(py_mod = PyImport_ImportModule(name))) { /* NEWREF */
	198	PyErr_Print(); /* Returns void. */
	199	return SRD_ERR_PYTHON; /* TODO: More specific error? */
	200	}
	201
	202	/* Get the 'register' function name as Python callable object. */
	203	py_func = PyObject_GetAttrString(py_mod, "register"); /* NEWREF */
	204	if (!py_func \|\| !PyCallable_Check(py_func)) {
	205	if (PyErr_Occurred())
	206	PyErr_Print(); /* Returns void. */
	207	Py_XDECREF(py_mod);
	208	return SRD_ERR_PYTHON; /* TODO: More specific error? */
	209	}
	210
	211	/* Call the 'register' function without arguments, get the result. */
	212	if (!(py_res = PyObject_CallFunction(py_func, NULL))) { /* NEWREF */
	213	PyErr_Print(); /* Returns void. */
	214	Py_XDECREF(py_func);
	215	Py_XDECREF(py_mod);
	216	return SRD_ERR_PYTHON; /* TODO: More specific error? */
	217	}
	218
	219	if (!(d = malloc(sizeof(struct srd_decoder))))
	220	return SRD_ERR_MALLOC;
	221
	222	if ((r = h_str(py_res, py_func, py_mod, "id", &(d->id))) < 0)
	223	return r;
	224
	225	if ((r = h_str(py_res, py_func, py_mod, "name", &(d->name))) < 0)
	226	return r;
	227
	228	if ((r = h_str(py_res, py_func, py_mod, "longname",
	229	&(d->longname))) < 0)
	230	return r;
	231
	232	if ((r = h_str(py_res, py_func, py_mod, "desc", &(d->desc))) < 0)
	233	return r;
	234
	235	if ((r = h_str(py_res, py_func, py_mod, "longdesc",
	236	&(d->longdesc))) < 0)
	237	return r;
	238
	239	if ((r = h_str(py_res, py_func, py_mod, "author", &(d->author))) < 0)
	240	return r;
	241
	242	if ((r = h_str(py_res, py_func, py_mod, "email", &(d->email))) < 0)
	243	return r;
	244
	245	if ((r = h_str(py_res, py_func, py_mod, "license", &(d->license))) < 0)
	246	return r;
	247
	248	d->py_mod = py_mod;
	249
	250	Py_XDECREF(py_res);
	251	Py_XDECREF(py_func);
	252
	253	/* Get the 'decode' function name as Python callable object. */
	254	py_func = PyObject_GetAttrString(py_mod, "decode"); /* NEWREF */
	255	if (!py_func \|\| !PyCallable_Check(py_func)) {
	256	if (PyErr_Occurred())
	257	PyErr_Print(); /* Returns void. */
	258	Py_XDECREF(py_mod);
	259	return SRD_ERR_PYTHON; /* TODO: More specific error? */
	260	}
	261
	262	d->py_func = py_func;
	263
	264	/* TODO: Handle func, inputformats, outputformats. */
	265	/* Note: They must at least be set to NULL, will segfault otherwise. */
	266	d->func = NULL;
	267	d->inputformats = NULL;
	268	d->outputformats = NULL;
	269
	270	*dec = d;
	271
	272	return SRD_OK;
	273	}
	274
	275	/**
	276	* Run the specified decoder function.
	277	*
	278	* @param dec TODO
	279	* @param inbuf TODO
	280	* @param inbuflen TODO
	281	* @param outbuf TODO
	282	* @param outbuflen TODO
	283	*
	284	* @return SRD_OK upon success, a (negative) error code otherwise.
	285	*/
	286	int srd_run_decoder(struct srd_decoder *dec,
	287	uint8_t *inbuf, uint64_t inbuflen,
	288	uint8_t *outbuf, uint64_t outbuflen)
	289	{
	290	PyObject py_mod, py_func, py_args, py_value, *py_res;
	291	int r, ret;
	292
	293	/* TODO: Use #defines for the return codes. */
	294
	295	/* Return an error upon unusable input. */
	296	if (dec == NULL)
	297	return SRD_ERR_ARGS; /* TODO: More specific error? */
	298	if (inbuf == NULL)
	299	return SRD_ERR_ARGS; /* TODO: More specific error? */
	300	if (inbuflen == 0) /* No point in working on empty buffers. */
	301	return SRD_ERR_ARGS; /* TODO: More specific error? */
	302	if (outbuf == NULL)
	303	return SRD_ERR_ARGS; /* TODO: More specific error? */
	304	if (outbuflen == NULL)
	305	return SRD_ERR_ARGS; /* TODO: More specific error? */
	306
	307	/* TODO: Error handling. */
	308	py_mod = dec->py_mod;
	309	Py_XINCREF(py_mod);
	310	py_func = dec->py_func;
	311	Py_XINCREF(py_func);
	312
	313	/* Create a Python tuple of size 1. */
	314	if (!(py_args = PyTuple_New(1))) { /* NEWREF */
	315	ret = SRD_ERR_PYTHON; /* TODO: More specific error? */
	316	goto err_run_decref_func;
	317	}
	318
	319	/* Get the input buffer as Python "string" (byte array). */
	320	/* TODO: int vs. uint64_t for 'inbuflen'? */
	321	if (!(py_value = Py_BuildValue("s#", inbuf, inbuflen))) { /* NEWREF */
	322	ret = SRD_ERR_PYTHON; /* TODO: More specific error? */
	323	goto err_run_decref_args;
	324	}
	325
	326	/*
	327	* IMPORTANT: PyTuple_SetItem() "steals" a reference to py_value!
	328	* That means we are no longer responsible for Py_XDECREF()'ing it.
	329	* It will automatically be free'd when the 'py_args' tuple is free'd.
	330	*/
	331	if (PyTuple_SetItem(py_args, 0, py_value) != 0) { /* STEAL */
	332	ret = SRD_ERR_PYTHON; /* TODO: More specific error? */
	333	Py_XDECREF(py_value); /* TODO: Ref. stolen upon error? */
	334	goto err_run_decref_args;
	335	}
	336
	337	if (!(py_res = PyObject_CallObject(py_func, py_args))) { /* NEWREF */
	338	ret = SRD_ERR_PYTHON; /* TODO: More specific error? */
	339	goto err_run_decref_args;
	340	}
	341
	342	if ((r = PyObject_AsCharBuffer(py_res, (const char **)outbuf,
	343	(Py_ssize_t *)outbuflen))) {
	344	ret = SRD_ERR_PYTHON; /* TODO: More specific error? */
	345	Py_XDECREF(py_res);
	346	goto err_run_decref_args;
	347	}
	348
	349	ret = SRD_OK;
	350
	351	Py_XDECREF(py_res);
	352
	353	err_run_decref_args:
	354	Py_XDECREF(py_args);
	355	err_run_decref_func:
	356	Py_XDECREF(py_func);
	357	Py_XDECREF(py_mod);
	358
	359	if (PyErr_Occurred())
	360	PyErr_Print(); /* Returns void. */
	361
	362	return ret;
	363	}
	364
	365	/**
	366	* TODO
	367	*/
	368	static int srd_unload_decoder(struct srd_decoder *dec)
	369	{
	370	g_free(dec->id);
	371	g_free(dec->name);
	372	g_free(dec->desc);
	373	g_free(dec->func);
	374
	375	/* TODO: Free everything in inputformats and outputformats. */
	376
	377	if (dec->inputformats != NULL)
	378	g_slist_free(dec->inputformats);
	379	if (dec->outputformats != NULL)
	380	g_slist_free(dec->outputformats);
	381
	382	Py_XDECREF(dec->py_func);
	383	Py_XDECREF(dec->py_mod);
	384
	385	return SRD_OK;
	386	}
	387
	388	/**
	389	* TODO
	390	*/
	391	static int srd_unload_all_decoders(void)
	392	{
	393	GSList *l;
	394	struct srd_decoder *dec;
	395
	396	for (l = srd_list_decoders(); l; l = l->next) {
	397	dec = l->data;
	398	/* TODO: Error handling. */
	399	srd_unload_decoder(dec);
	400	}
	401
	402	return SRD_OK;
	403	}
	404
	405	/**
	406	* Shutdown libsigrokdecode.
	407	*
	408	* @return SRD_OK upon success, a (negative) error code otherwise.
	409	*/
	410	int srd_exit(void)
	411	{
	412	/* Unload/free all decoders, and then the list of decoders itself. */
	413	/* TODO: Error handling. */
	414	srd_unload_all_decoders();
	415	g_slist_free(list_pds);
	416
	417	/* Py_Finalize() returns void, any finalization errors are ignored. */
	418	Py_Finalize();
	419
	420	return SRD_OK;
	421	}