[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 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 SIGROKDECODE_ERR_DECODERS_DIR;

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

	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
1c6fa20f UH	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>
5c55017c	23	#include <string.h>
7c24d086	24	#include <dirent.h>
1c6fa20f	25
e6c7a826 UH	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
7c24d086	33	/* The list of protocol decoders. */
871d21e2	34	GSList *list_pds = NULL;
7c24d086	35
1c6fa20f UH	36	/**
	37	* Initialize libsigrokdecode.
	38	*
70e44845	39	* @return SIGROKDECODE_OK upon success, a (negative) error code otherwise.
1c6fa20f UH	40	*/
	41	int sigrokdecode_init(void)
	42	{
7c24d086 UH	43	DIR *dir;
	44	struct dirent *dp;
	45	char *tmp;
	46
1c6fa20f UH	47	/* Py_Initialize() returns void and usually cannot fail. */
	48	Py_Initialize();
	49
0895f56a	50	/* Add search directory for the protocol decoders. */
2454527d	51	/* FIXME: Check error code. */
70e44845	52	/* FIXME: What happens if this function is called multiple times? */
0895f56a	53	PyRun_SimpleString("import sys;"
10426068	54	"sys.path.append(r'" DECODERS_DIR "');");
1c6fa20f	55
7c24d086 UH	56	if (!(dir = opendir(DECODERS_DIR)))
	57	return SIGROKDECODE_ERR_DECODERS_DIR;
	58
	59	while ((dp = readdir(dir)) != NULL) {
276b55eb	60	if (!g_str_has_suffix(dp->d_name, ".py"))
7c24d086	61	continue;
5b05904d UH	62	/* For now use the filename (without .py) as decoder name. */
5b05904d UH	63	if ((tmp = g_strndup(dp->d_name, strlen(dp->d_name) - 3)))
7c24d086 UH	64	list_pds = g_slist_append(list_pds, tmp);
	65	}
	66	closedir(dir);
	67
70e44845	68	return SIGROKDECODE_OK;
1c6fa20f UH	69	}
1c6fa20f UH	70
871d21e2 UH	71	/**
	72	* Returns the list of supported/loaded protocol decoders.
	73	*
	74	* This is a GSList containing the names of the decoders as strings.
	75	*
	76	* @return List of decoders, NULL if none are supported or loaded.
	77	*/
	78	GSList *sigrokdecode_list_decoders(void)
	79	{
	80	return list_pds;
	81	}
	82
5c55017c UH	83	/**
	84	* Helper function to handle Python strings.
	85	*
	86	* TODO: @param entries.
	87	*
70e44845 UH	88	* @return LIBSIGROKDECODE_OK upon success, a (negative) error code otherwise.
70e44845 UH	89	* The 'outstr' argument points to a malloc()ed string upon success.
5c55017c UH	90	*/
	91	static int h_str(PyObject py_res, PyObject py_func, PyObject *py_mod,
	92	const char key, char *outstr)
	93	{
	94	PyObject *py_str;
	95	char *str;
	96
	97	py_str = PyMapping_GetItemString(py_res, (char *)key);
	98	if (!py_str \|\| !PyString_Check(py_str)) {
	99	if (PyErr_Occurred())
	100	PyErr_Print();
	101	Py_DECREF(py_func);
	102	Py_DECREF(py_mod);
	103	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	104	}
	105
	106	if (!(str = PyString_AsString(py_str))) {
	107	if (PyErr_Occurred())
	108	PyErr_Print();
	109	Py_DECREF(py_str);
	110	Py_DECREF(py_func);
	111	Py_DECREF(py_mod);
	112	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	113	}
	114
	115	if (!(*outstr = strdup(str))) {
	116	if (PyErr_Occurred())
	117	PyErr_Print();
	118	Py_DECREF(py_str);
	119	Py_DECREF(py_func);
	120	Py_DECREF(py_mod);
	121	return SIGROKDECODE_ERR_MALLOC;
	122	}
	123
	124	Py_DECREF(py_str);
	125
70e44845	126	return SIGROKDECODE_OK;
5c55017c UH	127	}
5c55017c UH	128
1c6fa20f UH	129	/**
	130	* TODO
	131	*
	132	* @param name TODO
70e44845 UH	133	*
70e44845 UH	134	* @return LIBSIGROKDECODE_OK upon success, a (negative) error code otherwise.
1c6fa20f	135	*/
5c55017c UH	136	int sigrokdecode_load_decoder(const char *name,
5c55017c UH	137	struct sigrokdecode_decoder **dec)
1c6fa20f	138	{
5c55017c UH	139	struct sigrokdecode_decoder *d;
	140	PyObject py_name, py_mod, py_func, py_res /* , py_tuple /;
	141	int r;
	142
	143	/* Get the name of the decoder module as Python string. */
	144	if (!(py_name = PyString_FromString(name))) {
	145	PyErr_Print();
	146	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	147	}
	148
	149	/* "Import" the Python module. */
	150	if (!(py_mod = PyImport_Import(py_name))) {
	151	PyErr_Print();
	152	Py_DECREF(py_name);
	153	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	154	}
	155	Py_DECREF(py_name);
	156
	157	/* Get the 'register' function name as Python callable object. */
	158	py_func = PyObject_GetAttrString(py_mod, "register");
	159	if (!py_func \|\| !PyCallable_Check(py_func)) {
	160	if (PyErr_Occurred())
	161	PyErr_Print();
	162	Py_DECREF(py_mod);
	163	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	164	}
	165
	166	/* Call the 'register' function without arguments, get the result. */
	167	if (!(py_res = PyObject_CallFunction(py_func, NULL))) {
	168	PyErr_Print();
	169	Py_DECREF(py_func);
	170	Py_DECREF(py_mod);
	171	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	172	}
	173
	174	if (!(d = malloc(sizeof(struct sigrokdecode_decoder))))
	175	return SIGROKDECODE_ERR_MALLOC;
	176
	177	if ((r = h_str(py_res, py_func, py_mod, "id", &(d->id))) < 0)
	178	return r;
	179
	180	if ((r = h_str(py_res, py_func, py_mod, "name", &(d->name))) < 0)
	181	return r;
	182
	183	if ((r = h_str(py_res, py_func, py_mod, "desc", &(d->desc))) < 0)
	184	return r;
	185
	186	d->py_mod = py_mod;
	187
	188	Py_DECREF(py_res);
	189	Py_DECREF(py_func);
	190
	191	/* Get the 'decode' function name as Python callable object. */
	192	py_func = PyObject_GetAttrString(py_mod, "decode");
	193	if (!py_func \|\| !PyCallable_Check(py_func)) {
	194	if (PyErr_Occurred())
	195	PyErr_Print();
	196	Py_DECREF(py_mod);
	197	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
	198	}
	199
	200	d->py_func = py_func;
	201
	202	/* TODO: Handle inputformats, outputformats. */
203
204	*dec = d;
910e5fd8	205
70e44845	206	return SIGROKDECODE_OK;
1c6fa20f UH	207	}
	208
	209	/**
	210	* Run the specified decoder function.
	211	*
5c55017c	212	* @param dec TODO
1c6fa20f UH	213	* @param inbuf TODO
	214	* @param inbuflen TODO
	215	* @param outbuf TODO
	216	* @param outbuflen TODO
70e44845 UH	217	*
70e44845 UH	218	* @return LIBSIGROKDECODE_OK upon success, a (negative) error code otherwise.
1c6fa20f	219	*/
5c55017c	220	int sigrokdecode_run_decoder(struct sigrokdecode_decoder *dec,
2b45dd71	221	uint8_t *inbuf, uint64_t inbuflen,
2b45dd71	222	uint8_t *outbuf, uint64_t outbuflen)
1c6fa20f	223	{
5c55017c	224	PyObject py_mod, py_func, py_args, py_value, *py_res;
1c6fa20f UH	225	int ret;
	226
	227	/* TODO: Use #defines for the return codes. */
	228
	229	/* Return an error upon unusable input. */
5c55017c UH	230	if (dec == NULL)
5c55017c UH	231	return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
1c6fa20f	232	if (inbuf == NULL)
5c55017c	233	return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
1c6fa20f	234	if (inbuflen == 0) /* No point in working on empty buffers. */
5c55017c	235	return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
1c6fa20f	236	if (outbuf == NULL)
5c55017c	237	return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
1c6fa20f	238	if (outbuflen == NULL)
5c55017c	239	return SIGROKDECODE_ERR_ARGS; /* TODO: More specific error? */
1c6fa20f	240
5c55017c UH	241	/* TODO: Error handling. */
	242	py_mod = dec->py_mod;
	243	py_func = dec->py_func;
1c6fa20f	244
5c55017c	245	/* TODO: Really run Py_DECREF on py_mod/py_func? */
1c6fa20f UH	246
	247	/* Create a Python tuple of size 1. */
	248	if (!(py_args = PyTuple_New(1))) {
	249	PyErr_Print();
	250	Py_DECREF(py_func);
5c55017c UH	251	Py_DECREF(py_mod);
5c55017c UH	252	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
1c6fa20f UH	253	}
	254
	255	/* Get the input buffer as Python "string" (byte array). */
	256	/* TODO: int vs. uint64_t for 'inbuflen'? */
	257	if (!(py_value = Py_BuildValue("s#", inbuf, inbuflen))) {
	258	PyErr_Print();
	259	Py_DECREF(py_args);
	260	Py_DECREF(py_func);
5c55017c UH	261	Py_DECREF(py_mod);
5c55017c UH	262	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
1c6fa20f UH	263	}
	264
	265	if (PyTuple_SetItem(py_args, 0, py_value) != 0) {
	266	PyErr_Print();
	267	Py_DECREF(py_value);
	268	Py_DECREF(py_args);
	269	Py_DECREF(py_func);
5c55017c UH	270	Py_DECREF(py_mod);
5c55017c UH	271	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
1c6fa20f UH	272	}
1c6fa20f UH	273
5c55017c	274	if (!(py_res = PyObject_CallObject(py_func, py_args))) {
1c6fa20f UH	275	PyErr_Print();
	276	Py_DECREF(py_value);
	277	Py_DECREF(py_args);
	278	Py_DECREF(py_func);
5c55017c UH	279	Py_DECREF(py_mod);
5c55017c UH	280	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
1c6fa20f UH	281	}
1c6fa20f UH	282
5c55017c	283	if ((ret = PyObject_AsCharBuffer(py_res, (const char **)outbuf,
1c6fa20f UH	284	(Py_ssize_t *)outbuflen))) {
1c6fa20f UH	285	PyErr_Print();
5c55017c	286	Py_DECREF(py_res);
1c6fa20f UH	287	Py_DECREF(py_value);
	288	Py_DECREF(py_args);
	289	Py_DECREF(py_func);
5c55017c UH	290	Py_DECREF(py_mod);
5c55017c UH	291	return SIGROKDECODE_ERR_PYTHON; /* TODO: More specific error? */
1c6fa20f UH	292	}
1c6fa20f UH	293
5c55017c	294	Py_DECREF(py_res);
1c6fa20f UH	295	// Py_DECREF(py_value);
	296	Py_DECREF(py_args);
	297	Py_DECREF(py_func);
5c55017c	298	Py_DECREF(py_mod);
1c6fa20f	299
70e44845	300	return SIGROKDECODE_OK;
1c6fa20f UH	301	}
	302
	303	/**
	304	* Shutdown libsigrokdecode.
	305	*
70e44845	306	* @return LIBSIGROKDECODE_OK upon success, a (negative) error code otherwise.
1c6fa20f UH	307	*/
	308	int sigrokdecode_shutdown(void)
	309	{
	310	/* Py_Finalize() returns void, any finalization errors are ignored. */
	311	Py_Finalize();
	312
70e44845	313	return SIGROKDECODE_OK;
1c6fa20f	314	}