X-Git-Url: https://sigrok.org/gitweb/?p=libsigrokdecode.git;a=blobdiff_plain;f=decoder.c;h=83735a7ec3442ae30a199393b376db0b5a1d6836;hp=957d3a2417560e2b7a13db99bef8a81e35cf8e51;hb=fa12a21e3c779df4e33dcfe394e2ded3f96028ce;hpb=64c29e28e0efa184319f7831b3eca18c7f73f7d0

diff --git a/decoder.c b/decoder.c
index 957d3a2..83735a7 100644
--- a/decoder.c
+++ b/decoder.c
@@ -2,7 +2,7 @@
  * 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>
+ * Copyright (C) 2012 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
@@ -18,10 +18,10 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <glib.h>
 #include "config.h"
 #include "sigrokdecode.h" /* First, so we avoid a _POSIX_C_SOURCE warning. */
 #include "sigrokdecode-internal.h"
+#include <glib.h>
 
 /* The list of protocol decoders. */
 GSList *pd_list = NULL;
@@ -65,6 +65,63 @@ struct srd_decoder *srd_get_decoder_by_id(const char *id)
 }
 
 
+static int get_probes(struct srd_decoder *d, char *attr, GSList **pl)
+{
+	PyObject *py_probelist, *py_entry;
+	struct srd_probe *p;
+	int ret, num_probes, i;
+
+	if (!PyObject_HasAttrString(d->py_dec, attr))
+		/* No probes of this type specified. */
+		return SRD_OK;
+
+	ret = SRD_ERR_PYTHON;
+	py_probelist = py_entry = NULL;
+
+	py_probelist = PyObject_GetAttrString(d->py_dec, attr);
+	if (!PyList_Check(py_probelist)) {
+		srd_err("Protocol decoder %s %s attribute is not "
+				"a list.", d->name, attr);
+		goto err_out;
+	}
+
+	num_probes = PyList_Size(py_probelist);
+	if (num_probes == 0)
+		/* Empty probelist. */
+		return SRD_OK;
+
+	for (i = 0; i < num_probes; i++) {
+		py_entry = PyList_GetItem(py_probelist, i);
+		if (!PyDict_Check(py_entry)) {
+			srd_err("Protocol decoder %s %s attribute is not "
+					"a list with dict elements.", d->name, attr);
+			goto err_out;
+		}
+
+		if (!(p = g_try_malloc(sizeof(struct srd_probe)))) {
+			ret = SRD_ERR_MALLOC;
+			goto err_out;
+		}
+
+		if ((py_dictitem_as_str(py_entry, "id", &p->id)) != SRD_OK)
+			goto err_out;
+		if ((py_dictitem_as_str(py_entry, "name", &p->name)) != SRD_OK)
+			goto err_out;
+		if ((py_dictitem_as_str(py_entry, "desc", &p->desc)) != SRD_OK)
+			goto err_out;
+		p->order = i;
+
+		*pl = g_slist_append(*pl, p);
+	}
+	ret = SRD_OK;
+
+err_out:
+	Py_DecRef(py_entry);
+	Py_DecRef(py_probelist);
+
+	return ret;
+}
+
 /**
  * Load a protocol decoder module into the embedded Python interpreter.
  *
@@ -75,80 +132,112 @@ struct srd_decoder *srd_get_decoder_by_id(const char *id)
  */
 int srd_load_decoder(const char *name, struct srd_decoder **dec)
 {
-	PyObject *py_basedec, *py_annlist, *py_ann;
+	PyObject *py_basedec, *py_method, *py_attr, *py_annlist, *py_ann;
 	struct srd_decoder *d;
 	int alen, ret, i;
 	char **ann;
 
-	py_basedec = NULL;
-	ret = SRD_ERR;
+	srd_dbg("Loading module '%s'.", name);
 
-	srd_dbg("decoder: %s: loading module '%s'", __func__, name);
+	py_basedec = py_method = py_attr = NULL;
 
 	if (!(d = g_try_malloc0(sizeof(struct srd_decoder)))) {
-		srd_err("decoder: %s: d malloc failed", __func__);
+		srd_dbg("Failed to malloc struct srd_decoder.");
 		ret = SRD_ERR_MALLOC;
 		goto err_out;
 	}
 
+	ret = SRD_ERR_PYTHON;
+
 	/* Import the Python module. */
 	if (!(d->py_mod = PyImport_ImportModule(name))) {
-		/* TODO: Report exception message/traceback to err/dbg. */
-		srd_warn("decoder: %s: import of '%s' failed", __func__, name);
-		PyErr_Print();
-		PyErr_Clear();
-		ret = SRD_ERR_PYTHON;
+		catch_exception("import of '%s' failed.", name);
 		goto err_out;
 	}
 
 	/* Get the 'Decoder' class as Python object. */
 	if (!(d->py_dec = PyObject_GetAttrString(d->py_mod, "Decoder"))) {
 		/* This generated an AttributeError exception. */
-		PyErr_Print();
 		PyErr_Clear();
-		srd_err("Decoder class not found in protocol decoder module %s", name);
-		ret = SRD_ERR_PYTHON;
+		srd_err("Decoder class not found in protocol decoder %s.", name);
 		goto err_out;
 	}
 
 	if (!(py_basedec = PyObject_GetAttrString(mod_sigrokdecode, "Decoder"))) {
-		srd_dbg("sigrokdecode module not loaded");
-		ret = SRD_ERR_PYTHON;
+		srd_dbg("sigrokdecode module not loaded.");
 		goto err_out;
 	}
 
 	if (!PyObject_IsSubclass(d->py_dec, py_basedec)) {
 		srd_err("Decoder class in protocol decoder module %s is not "
-				"a subclass of sigrokdecode.Decoder", name);
-		ret = SRD_ERR_PYTHON;
+				"a subclass of sigrokdecode.Decoder.", name);
 		goto err_out;
 	}
-	Py_DecRef(py_basedec);
+	Py_CLEAR(py_basedec);
 
-	if (py_attr_as_str(d->py_dec, "id", &(d->id)) != SRD_OK) {
-		return SRD_ERR_PYTHON;
+	/* Check for a proper start() method. */
+	if (!PyObject_HasAttrString(d->py_dec, "start")) {
+		srd_err("Protocol decoder %s has no start() method Decoder "
+				"class.", name);
 		goto err_out;
 	}
-
-	if (py_attr_as_str(d->py_dec, "name", &(d->name)) != SRD_OK) {
-		return SRD_ERR_PYTHON;
+	py_method = PyObject_GetAttrString(d->py_dec, "start");
+	if (!PyFunction_Check(py_method)) {
+		srd_err("Protocol decoder %s Decoder class attribute 'start' "
+				"is not a method.", name);
 		goto err_out;
 	}
+	Py_CLEAR(py_method);
 
-	if (py_attr_as_str(d->py_dec, "longname", &(d->longname)) != SRD_OK) {
-		return SRD_ERR_PYTHON;
+	/* Check for a proper decode() method. */
+	if (!PyObject_HasAttrString(d->py_dec, "decode")) {
+		srd_err("Protocol decoder %s has no decode() method Decoder "
+				"class.", name);
 		goto err_out;
 	}
-
-	if (py_attr_as_str(d->py_dec, "desc", &(d->desc)) != SRD_OK) {
-		return SRD_ERR_PYTHON;
+	py_method = PyObject_GetAttrString(d->py_dec, "decode");
+	if (!PyFunction_Check(py_method)) {
+		srd_err("Protocol decoder %s Decoder class attribute 'decode' "
+				"is not a method.", name);
 		goto err_out;
 	}
+	Py_CLEAR(py_method);
+
+	/* If present, options must be a dictionary. */
+	if (PyObject_HasAttrString(d->py_dec, "options")) {
+		py_attr = PyObject_GetAttrString(d->py_dec, "options");
+		if (!PyDict_Check(py_attr)) {
+			srd_err("Protocol decoder %s options attribute is not "
+					"a dictionary.", d->name);
+			Py_DecRef(py_attr);
+			goto err_out;
+		}
+		Py_DecRef(py_attr);
+	}
 
-	if (py_attr_as_str(d->py_dec, "license", &(d->license)) != SRD_OK) {
-		return SRD_ERR_PYTHON;
+	/* Check and import required probes. */
+	if (get_probes(d, "probes", &d->probes) != SRD_OK)
+		goto err_out;
+
+	/* Check and import optional probes. */
+	if (get_probes(d, "extra_probes", &d->extra_probes) != SRD_OK)
+		goto err_out;
+
+	/* Store required fields in newly allocated strings. */
+	if (py_attr_as_str(d->py_dec, "id", &(d->id)) != SRD_OK)
+		goto err_out;
+
+	if (py_attr_as_str(d->py_dec, "name", &(d->name)) != SRD_OK)
+		goto err_out;
+
+	if (py_attr_as_str(d->py_dec, "longname", &(d->longname)) != SRD_OK)
+		goto err_out;
+
+	if (py_attr_as_str(d->py_dec, "desc", &(d->desc)) != SRD_OK)
+		goto err_out;
+
+	if (py_attr_as_str(d->py_dec, "license", &(d->license)) != SRD_OK)
 		goto err_out;
-	}
 
 	/* TODO: Handle inputformats, outputformats. */
 	d->inputformats = NULL;
@@ -159,22 +248,19 @@ int srd_load_decoder(const char *name, struct srd_decoder **dec)
 	if (PyObject_HasAttrString(d->py_dec, "annotations")) {
 		py_annlist = PyObject_GetAttrString(d->py_dec, "annotations");
 		if (!PyList_Check(py_annlist)) {
-			srd_err("Protocol decoder module %s annotations should be a list", name);
-			ret = SRD_ERR_PYTHON;
+			srd_err("Protocol decoder module %s annotations should be a list.", name);
 			goto err_out;
 		}
 		alen = PyList_Size(py_annlist);
 		for (i = 0; i < alen; i++) {
 			py_ann = PyList_GetItem(py_annlist, i);
 			if (!PyList_Check(py_ann) || PyList_Size(py_ann) != 2) {
-				srd_err("Protocol decoder module %s annotation %d should be a list with two elements",
-						name, i+1);
-				ret = SRD_ERR_PYTHON;
+				srd_err("Protocol decoder module %s annotation %d should "
+						"be a list with two elements.", name, i+1);
 				goto err_out;
 			}
 
 			if (py_strlist_to_char(py_ann, &ann) != SRD_OK) {
-				ret = SRD_ERR_PYTHON;
 				goto err_out;
 			}
 			d->annotations = g_slist_append(d->annotations, ann);
@@ -186,6 +272,7 @@ int srd_load_decoder(const char *name, struct srd_decoder **dec)
 
 err_out:
 	if (ret != SRD_OK) {
+		Py_XDECREF(py_method);
 		Py_XDECREF(py_basedec);
 		Py_XDECREF(d->py_dec);
 		Py_XDECREF(d->py_mod);
@@ -204,7 +291,7 @@ char *srd_decoder_doc(struct srd_decoder *dec)
 		return NULL;
 
 	if (!(py_str = PyObject_GetAttrString(dec->py_mod, "__doc__"))) {
-		PyErr_Clear();
+		catch_exception("");
 		return NULL;
 	}
 
@@ -217,16 +304,45 @@ char *srd_decoder_doc(struct srd_decoder *dec)
 }
 
 
+static void free_probes(GSList *probelist)
+{
+	GSList *l;
+	struct srd_probe *p;
+
+	if (probelist == NULL)
+		return;
+
+	for (l = probelist; l; l = l->next) {
+		p = l->data;
+		g_free(p->id);
+		g_free(p->name);
+		g_free(p->desc);
+		g_free(p);
+	}
+	g_slist_free(probelist);
+
+}
+
 /**
  * Unload decoder module.
  *
- * @param dec The decoder struct to be unloaded.
+ * @param dec The struct srd_decoder to be unloaded.
  *
  * @return SRD_OK upon success, a (negative) error code otherwise.
  */
 int srd_unload_decoder(struct srd_decoder *dec)
 {
 
+	srd_dbg("unloading decoder %s", dec->name);
+
+	/* Since any instances of this decoder need to be released as well,
+	 * but they could be anywhere in the stack, just free the entire
+	 * stack. A frontend reloading a decoder thus has to restart all
+	 * instances, and rebuild the stack. */
+	srd_instance_free_all(NULL);
+
+	free_probes(dec->probes);
+	free_probes(dec->extra_probes);
 	g_free(dec->id);
 	g_free(dec->name);
 	g_free(dec->longname);
@@ -239,7 +355,9 @@ int srd_unload_decoder(struct srd_decoder *dec)
 	if (dec->outputformats != NULL)
 		g_slist_free(dec->outputformats);
 
+	/* The module's Decoder class. */
 	Py_XDECREF(dec->py_dec);
+	/* The module itself. */
 	Py_XDECREF(dec->py_mod);
 
 	/* TODO: (g_)free dec itself? */
@@ -247,126 +365,23 @@ int srd_unload_decoder(struct srd_decoder *dec)
 	return SRD_OK;
 }
 
-/**
- * Check if the directory in the specified search path is a valid PD dir.
- *
- * A valid sigrok protocol decoder consists of a directory, which contains
- * at least two .py files (the special __init__.py and at least one additional
- * .py file which contains the actual PD code).
- *
- * TODO: We should also check that this is not a random other Python module,
- * but really a sigrok PD module by some means.
- *
- * @param search_path A string containing the (absolute) path to the directory
- *                    where 'entry' resides in.
- * @param entry A string containing the (relative) directory name of the
- *              sigrok PD module. E.g. "i2c" for the I2C protocol decoder.
- * @return SRD_OK, if the directory is a valid sigrok PD, a negative error
- *         code, such as SRD_ERR, otherwise.
- */
-int srd_is_valid_pd_dir(const gchar *search_path, const gchar *entry)
-{
-	GDir *dir;
-	int py_files = 0, has_init_py = 0;
-	gchar *path1, *path2, *file;
-	GError *error;
-
-	/* TODO: Error handling. */
-	path1 = g_build_filename(search_path, entry, NULL);
-
-	/* Check that it is a directory (and exists). */
-	if (!g_file_test(path1, G_FILE_TEST_IS_DIR)) {
-		srd_dbg("decoder: %s: '%s' not a directory or doesn't exist",
-			__func__, entry);
-		return SRD_ERR;
-	}
-
-	if (!(dir = g_dir_open(path1, 0, &error))) { /* TODO: flags? */
-		srd_dbg("decoder: %s: '%s' failed to open directory",
-			__func__, entry);
-		return SRD_ERR;
-	}
-
-	/* Check the contents of the directory. */
-	while ((file = g_dir_read_name(dir)) != NULL) {
-		/* TODO: Error handling. */
-		path2 = g_build_filename(path1, file, NULL);
-
-		/* Ignore non-files. */
-		if (!g_file_test(path2, G_FILE_TEST_IS_REGULAR)) {
-			srd_spew("decoder: %s: '%s' not a file, ignoring",
-				 __func__, file);
-			continue;
-		}
-
-		/* Count number of .py files. */
-		if (g_str_has_suffix(path2, ".py")) {
-			srd_spew("decoder: %s: found .py file: '%s'",
-				 __func__, file);
-			py_files++;
-		}
-
-		/* Check if it's an __init__.py file. */
-		if (g_str_has_suffix(path2, "__init__.py")) {
-			srd_spew("decoder: %s: found __init__.py file: '%s'",
-				 __func__, path2);
-			has_init_py = 1;
-		}
-	}
-	g_dir_close(dir);
-
-	/* Check if the directory contains >= 2 *.py files. */
-	if (py_files < 2) {
-		srd_dbg("decoder: %s: '%s' is not a valid PD dir, it doesn't "
-			"contain >= 2 .py files", __func__, entry);
-		return SRD_ERR;
-	}
-
-	/* Check if the directory contains an __init__.py file. */
-	if (!has_init_py) {
-		srd_dbg("decoder: %s: '%s' is not a valid PD dir, it doesn't "
-			"contain an __init__.py file", __func__, entry);
-		return SRD_ERR;
-	}
-
-	/* TODO: Check if it's a PD, not a random other Python module. */
-
-	return SRD_OK;
-}
-
 int srd_load_all_decoders(void)
 {
 	GDir *dir;
-	gchar *direntry;
+	GError *error;
+	struct srd_decoder *dec;
 	int ret;
+	const gchar *direntry;
 	char *decodername;
-	struct srd_decoder *dec;
-	GError *error;
 
-	if (!(dir = g_dir_open(DECODERS_DIR, 0, &error))) { /* TODO: flags? */
-		Py_Finalize(); /* Returns void. */
+	if (!(dir = g_dir_open(DECODERS_DIR, 0, &error))) {
 		return SRD_ERR_DECODERS_DIR;
 	}
 
 	while ((direntry = g_dir_read_name(dir)) != NULL) {
-		/* Ignore directory entries which are not valid PDs. */
-		if (srd_is_valid_pd_dir(DECODERS_DIR, direntry) != SRD_OK) {
-			srd_dbg("decoder: %s: '%s' not a valid PD dir, "
-				"ignoring it", __func__, direntry);
-			continue;
-		}
-
 		/* The decoder name is the PD directory name (e.g. "i2c"). */
 		decodername = g_strdup(direntry);
 
-		/* TODO: Error handling. Use g_try_malloc(). */
-		if (!(dec = malloc(sizeof(struct srd_decoder)))) {
-			Py_Finalize(); /* Returns void. */
-			return SRD_ERR_MALLOC;
-		}
-
-		/* Load the decoder. */
-		/* TODO: Warning if loading fails for a decoder. */
 		if ((ret = srd_load_decoder(decodername, &dec)) == SRD_OK) {
 			/* Append it to the list of supported/loaded decoders. */
 			pd_list = g_slist_append(pd_list, dec);
@@ -387,7 +402,6 @@ int srd_unload_all_decoders(void)
 
 	for (l = srd_list_decoders(); l; l = l->next) {
 		dec = l->data;
-		/* TODO: Error handling. */
 		srd_unload_decoder(dec);
 	}