Merge pull request #188 from PX4/param_command

Improved param command, show now allows to filter and set allows to set int params

apps/systemcmds/param/param.c

@@ -61,6 +61,7 @@ static void	do_load(const char* param_file_name);
 static void	do_import(const char* param_file_name);
 static void	do_show(const char* search_string);
 static void	do_show_print(void *arg, param_t param);
+static void	do_set(const char* name, const char* val);
 
 int
 param_main(int argc, char *argv[])
@@ -100,7 +101,7 @@ param_main(int argc, char *argv[])
 			exit(0);
 		}
 
-		if (!strcmp(argv[1], "show"))
+		if (!strcmp(argv[1], "show")) {
 			if (argc >= 3) {
 				do_show(argv[2]);
 			} else {
@@ -108,7 +109,16 @@ param_main(int argc, char *argv[])
 			}
 		}
 
-	errx(1, "expected a command, try 'load', 'import', 'show', 'select' or 'save'");
+		if (!strcmp(argv[1], "set")) {
+			if (argc >= 4) {
+				do_set(argv[2], argv[3]);
+			} else {
+				errx(1, "not enough arguments.\nTry 'param set PARAM_NAME 3'");
+			}
+		}
+	}
+	
+	errx(1, "expected a command, try 'load', 'import', 'show', 'set', 'select' or 'save'");
 }
 
 static void
@@ -185,9 +195,11 @@ do_show_print(void *arg, param_t param)
 	float f;
 	const char *search_string = (const char*)arg;
 
-	/* print nothing if search string valid and not matching */
-	if (arg != NULL && (strcmp(search_string, param_name(param) != 0)))
+	/* print nothing if search string is invalid and not matching */
+	if (!(arg == NULL || (!strcmp(search_string, param_name(param))))) {
+		/* param not found */
 		return;
+	}
 
 	printf("%c %s: ",
 	       param_value_unsaved(param) ? '*' : (param_value_is_default(param) ? ' ' : '+'),
@@ -225,3 +237,61 @@ do_show_print(void *arg, param_t param)
 
 	printf("<error fetching parameter %d>\n", param);
 }
+
+static void
+do_set(const char* name, const char* val)
+{
+	int32_t i;
+	float f;
+	param_t param = param_find(name);
+
+	/* set nothing if parameter cannot be found */
+	if (param == PARAM_INVALID) {
+		/* param not found */
+		errx(1, "Error: Parameter %s not found.", name);
+	}
+
+	printf("%c %s: ",
+	       param_value_unsaved(param) ? '*' : (param_value_is_default(param) ? ' ' : '+'),
+	       param_name(param));
+
+	/*
+	 * Set parameter if type is known and conversion from string to value turns out fine
+	 */
+
+	switch (param_type(param)) {
+	case PARAM_TYPE_INT32:
+		if (!param_get(param, &i)) {
+			printf("old: %d", i);
+
+			/* convert string */
+			char* end;
+			i = strtol(val,&end,10);
+			param_set(param, &i);
+			printf(" -> new: %d\n", i);
+
+		}
+
+		break;
+
+	case PARAM_TYPE_FLOAT:
+		if (!param_get(param, &f)) {
+			printf("float values are not yet supported.");
+			// printf("old: %4.4f", (double)f);
+
+			// /* convert string */
+			// char* end;
+			// f = strtof(val,&end);
+			// param_set(param, &f);
+			// printf(" -> new: %4.4f\n", f);
+
+		}
+
+		break;
+
+	default:
+		errx(1, "<unknown / unsupported type %d>\n", 0 + param_type(param));
+	}
+
+	exit(0);
+}