[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 <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;

/**
 * Initialize libsigrokdecode.
 *
 * @return SIGROKDECODE_OK upon success, a (negative) error code otherwise.
 */
int sigrokdecode_init(void)
{
	DIR *dir;
	struct dirent *dp;
	char *tmp;

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

	/* Add some more search directories for convenience. */
	/* 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 "');"
		);

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

	while ((dp = readdir(dir)) != NULL) {
		if (!strstr(dp->d_name, ".py"))
			continue;
		if ((tmp = strdup(dp->d_name)))
			list_pds = g_slist_append(list_pds, tmp);
	}
	closedir(dir);

	return SIGROKDECODE_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 *sigrokdecode_list_decoders(void)
{
	return list_pds;
}

/**
 * Helper function to handle Python strings.
 *
 * TODO: @param entries.
 *
 * @return LIBSIGROKDECODE_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;

	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? */
	}

	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? */
	}

	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;
	}

	Py_DECREF(py_str);

	return SIGROKDECODE_OK;
}

/**
 * TODO
 *
 * @param name TODO
 *
 * @return LIBSIGROKDECODE_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 */;
	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);
		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");
	if (!py_func || !PyCallable_Check(py_func)) {
		if (PyErr_Occurred())
			PyErr_Print();
		Py_DECREF(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);
		return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	}

	if (!(d = malloc(sizeof(struct sigrokdecode_decoder))))
		return SIGROKDECODE_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, "desc", &(d->desc))) < 0)
		return r;

	d->py_mod = py_mod;

	Py_DECREF(py_res);
	Py_DECREF(py_func);

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

	d->py_func = py_func;

	/* TODO: Handle inputformats, outputformats. */

	*dec = d;

	return SIGROKDECODE_OK;
}

/**
 * Run the specified decoder function.
 *
 * @param dec TODO
 * @param inbuf TODO
 * @param inbuflen TODO
 * @param outbuf TODO
 * @param outbuflen TODO
 *
 * @return LIBSIGROKDECODE_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;

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

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

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

	/* TODO: Really run Py_DECREF on py_mod/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? */
	}

	/* 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 (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? */
	}

	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 ((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? */
	}

	Py_DECREF(py_res);
	// Py_DECREF(py_value);
	Py_DECREF(py_args);
	Py_DECREF(py_func);
	Py_DECREF(py_mod);

	return SIGROKDECODE_OK;
}

/**
 * Shutdown libsigrokdecode.
 *
 * @return LIBSIGROKDECODE_OK upon success, a (negative) error code otherwise.
 */
int sigrokdecode_shutdown(void)
{
	/* Py_Finalize() returns void, any finalization errors are ignored. */
	Py_Finalize();

	return SIGROKDECODE_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 <sigrokdecode.h> /* First, so we avoid a _POSIX_C_SOURCE warning. */
	22	#include <stdio.h>
	23	#include <string.h>
	24	#include <dirent.h>
	25
	26	/* Re-define some string functions for Python >= 3.0. */
	27	#if PY_VERSION_HEX >= 0x03000000
	28	#define PyString_AsString PyBytes_AsString
	29	#define PyString_FromString PyBytes_FromString
	30	#define PyString_Check PyBytes_Check
	31	#endif
	32
	33	/* The list of protocol decoders. */
	34	GSList *list_pds = NULL;
	35
	36	/**
	37	* Initialize libsigrokdecode.
	38	*
	39	* @return SIGROKDECODE_OK upon success, a (negative) error code otherwise.
	40	*/
	41	int sigrokdecode_init(void)
	42	{
	43	DIR *dir;
	44	struct dirent *dp;
	45	char *tmp;
	46
	47	/* Py_Initialize() returns void and usually cannot fail. */
	48	Py_Initialize();
	49
	50	/* Add some more search directories for convenience. */
	51	/* FIXME: Check error code. */
	52	/* FIXME: What happens if this function is called multiple times? */
	53	PyRun_SimpleString(
	54	"import sys;"
	55	"sys.path.append('libsigrokdecode/decoders');"
	56	"sys.path.append('" DECODERS_DIR "');"
	57	);
	58
	59	if (!(dir = opendir(DECODERS_DIR)))
	60	return SIGROKDECODE_ERR_DECODERS_DIR;
	61
	62	while ((dp = readdir(dir)) != NULL) {
	63	if (!strstr(dp->d_name, ".py"))
	64	continue;
	65	if ((tmp = strdup(dp->d_name)))
	66	list_pds = g_slist_append(list_pds, tmp);
	67	}
	68	closedir(dir);
	69
	70	return SIGROKDECODE_OK;
	71	}
	72
	73	/**
	74	* Returns the list of supported/loaded protocol decoders.
	75	*
	76	* This is a GSList containing the names of the decoders as strings.
	77	*
	78	* @return List of decoders, NULL if none are supported or loaded.
	79	*/
	80	GSList *sigrokdecode_list_decoders(void)
	81	{
	82	return list_pds;
	83	}
	84
	85	/**
	86	* Helper function to handle Python strings.
	87	*
	88	* TODO: @param entries.
	89	*
	90	* @return LIBSIGROKDECODE_OK upon success, a (negative) error code otherwise.
	91	* The 'outstr' argument points to a malloc()ed string upon success.
	92	*/
	93	static int h_str(PyObject py_res, PyObject py_func, PyObject *py_mod,
	94	const char key, char *outstr)
	95	{
	96	PyObject *py_str;
	97	char *str;
	98
	99	py_str = PyMapping_GetItemString(py_res, (char *)key);
	100	if (!py_str \|\| !PyString_Check(py_str)) {
	101	if (PyErr_Occurred())
	102	PyErr_Print();
	103	Py_DECREF(py_func);
	104	Py_DECREF(py_mod);
	105	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	106	}
	107
	108	if (!(str = PyString_AsString(py_str))) {
	109	if (PyErr_Occurred())
	110	PyErr_Print();
	111	Py_DECREF(py_str);
	112	Py_DECREF(py_func);
	113	Py_DECREF(py_mod);
	114	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	115	}
	116
	117	if (!(*outstr = strdup(str))) {
	118	if (PyErr_Occurred())
	119	PyErr_Print();
	120	Py_DECREF(py_str);
	121	Py_DECREF(py_func);
	122	Py_DECREF(py_mod);
	123	return SIGROKDECODE_ERR_MALLOC;
	124	}
	125
	126	Py_DECREF(py_str);
	127
	128	return SIGROKDECODE_OK;
	129	}
	130
	131	/**
	132	* TODO
	133	*
	134	* @param name TODO
	135	*
	136	* @return LIBSIGROKDECODE_OK upon success, a (negative) error code otherwise.
	137	*/
	138	int sigrokdecode_load_decoder(const char *name,
	139	struct sigrokdecode_decoder **dec)
	140	{
	141	struct sigrokdecode_decoder *d;
	142	PyObject py_name, py_mod, py_func, py_res /* , py_tuple /;
	143	int r;
	144
	145	/* Get the name of the decoder module as Python string. */
	146	if (!(py_name = PyString_FromString(name))) {
	147	PyErr_Print();
	148	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	149	}
	150
	151	/* "Import" the Python module. */
	152	if (!(py_mod = PyImport_Import(py_name))) {
	153	PyErr_Print();
	154	Py_DECREF(py_name);
	155	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	156	}
	157	Py_DECREF(py_name);
	158
	159	/* Get the 'register' function name as Python callable object. */
	160	py_func = PyObject_GetAttrString(py_mod, "register");
	161	if (!py_func \|\| !PyCallable_Check(py_func)) {
	162	if (PyErr_Occurred())
	163	PyErr_Print();
	164	Py_DECREF(py_mod);
	165	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	166	}
	167
	168	/* Call the 'register' function without arguments, get the result. */
	169	if (!(py_res = PyObject_CallFunction(py_func, NULL))) {
	170	PyErr_Print();
	171	Py_DECREF(py_func);
	172	Py_DECREF(py_mod);
	173	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	174	}
	175
	176	if (!(d = malloc(sizeof(struct sigrokdecode_decoder))))
	177	return SIGROKDECODE_ERR_MALLOC;
	178
	179	if ((r = h_str(py_res, py_func, py_mod, "id", &(d->id))) < 0)
	180	return r;
	181
	182	if ((r = h_str(py_res, py_func, py_mod, "name", &(d->name))) < 0)
	183	return r;
	184
	185	if ((r = h_str(py_res, py_func, py_mod, "desc", &(d->desc))) < 0)
	186	return r;
	187
	188	d->py_mod = py_mod;
	189
	190	Py_DECREF(py_res);
	191	Py_DECREF(py_func);
	192
	193	/* Get the 'decode' function name as Python callable object. */
	194	py_func = PyObject_GetAttrString(py_mod, "decode");
	195	if (!py_func \|\| !PyCallable_Check(py_func)) {
	196	if (PyErr_Occurred())
	197	PyErr_Print();
	198	Py_DECREF(py_mod);
	199	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	200	}
	201
	202	d->py_func = py_func;
	203
	204	/* TODO: Handle inputformats, outputformats. */
	205
	206	*dec = d;
	207
	208	return SIGROKDECODE_OK;
	209	}
	210
	211	/**
	212	* Run the specified decoder function.
	213	*
	214	* @param dec TODO
	215	* @param inbuf TODO
	216	* @param inbuflen TODO
	217	* @param outbuf TODO
	218	* @param outbuflen TODO
	219	*
	220	* @return LIBSIGROKDECODE_OK upon success, a (negative) error code otherwise.
	221	*/
	222	int sigrokdecode_run_decoder(struct sigrokdecode_decoder *dec,
	223	uint8_t *inbuf, uint64_t inbuflen,
	224	uint8_t *outbuf, uint64_t outbuflen)
	225	{
	226	PyObject py_mod, py_func, py_args, py_value, *py_res;
	227	int ret;
	228
	229	/* TODO: Use #defines for the return codes. */
	230
	231	/* Return an error upon unusable input. */
	232	if (dec == NULL)
	233	return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
	234	if (inbuf == NULL)
	235	return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
	236	if (inbuflen == 0) /* No point in working on empty buffers. */
	237	return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
	238	if (outbuf == NULL)
	239	return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
	240	if (outbuflen == NULL)
	241	return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
	242
	243	/* TODO: Error handling. */
	244	py_mod = dec->py_mod;
	245	py_func = dec->py_func;
	246
	247	/* TODO: Really run Py_DECREF on py_mod/py_func? */
	248
	249	/* Create a Python tuple of size 1. */
	250	if (!(py_args = PyTuple_New(1))) {
	251	PyErr_Print();
	252	Py_DECREF(py_func);
	253	Py_DECREF(py_mod);
	254	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	255	}
	256
	257	/* Get the input buffer as Python "string" (byte array). */
	258	/* TODO: int vs. uint64_t for 'inbuflen'? */
	259	if (!(py_value = Py_BuildValue("s#", inbuf, inbuflen))) {
	260	PyErr_Print();
	261	Py_DECREF(py_args);
	262	Py_DECREF(py_func);
	263	Py_DECREF(py_mod);
	264	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	265	}
	266
	267	if (PyTuple_SetItem(py_args, 0, py_value) != 0) {
	268	PyErr_Print();
	269	Py_DECREF(py_value);
	270	Py_DECREF(py_args);
	271	Py_DECREF(py_func);
	272	Py_DECREF(py_mod);
	273	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	274	}
	275
	276	if (!(py_res = PyObject_CallObject(py_func, py_args))) {
	277	PyErr_Print();
	278	Py_DECREF(py_value);
	279	Py_DECREF(py_args);
	280	Py_DECREF(py_func);
	281	Py_DECREF(py_mod);
	282	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	283	}
	284
	285	if ((ret = PyObject_AsCharBuffer(py_res, (const char **)outbuf,
	286	(Py_ssize_t *)outbuflen))) {
	287	PyErr_Print();
	288	Py_DECREF(py_res);
	289	Py_DECREF(py_value);
	290	Py_DECREF(py_args);
	291	Py_DECREF(py_func);
	292	Py_DECREF(py_mod);
	293	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	294	}
	295
	296	Py_DECREF(py_res);
	297	// Py_DECREF(py_value);
	298	Py_DECREF(py_args);
	299	Py_DECREF(py_func);
	300	Py_DECREF(py_mod);
	301
	302	return SIGROKDECODE_OK;
	303	}
	304
	305	/**
	306	* Shutdown libsigrokdecode.
	307	*
	308	* @return LIBSIGROKDECODE_OK upon success, a (negative) error code otherwise.
	309	*/
	310	int sigrokdecode_shutdown(void)
	311	{
	312	/* Py_Finalize() returns void, any finalization errors are ignored. */
	313	Py_Finalize();
	314
	315	return SIGROKDECODE_OK;
	316	}