os: add app to transform kernel/core output to LOG

Issue #2207

repos/os/recipes/src/log_core/content.mk

@@ -0,0 +1,2 @@
+SRC_DIR = src/app/log_core
+include $(GENODE_DIR)/repos/base/recipes/src/content.inc

repos/os/recipes/src/log_core/hash

@@ -0,0 +1 @@
+2017-12-13-b 766edac0917548ff49d04226d07e314b5b05b48a

repos/os/recipes/src/log_core/used_apis

@@ -0,0 +1,3 @@
+base
+os
+timer_session

repos/os/run/log_core.run

@@ -0,0 +1,91 @@
+if {[have_spec linux]} {
+	puts "\n Run script is not supported on this platform. \n";
+	exit 0
+}
+if {[get_cmd_switch --autopilot] && ![have_include "power_on/qemu"]} {
+	puts "\n Run script is not supported on this platform. \n";
+	exit 0
+}
+
+proc log_service { } {
+	if { [get_cmd_switch --autopilot] } { return log }
+	return ram
+}
+
+build "core init drivers/timer server/vfs server/fs_log app/log_core"
+
+create_boot_directory
+
+install_config {
+<config>
+	<parent-provides>
+		<service name="CPU"/>
+		<service name="IO_PORT"/>
+		<service name="IRQ"/>
+		<service name="LOG"/>
+		<service name="PD"/>
+		<service name="RAM"/>
+		<service name="ROM"/>
+	</parent-provides>
+	<default-route>
+		<any-service> <parent/> </any-service>
+	</default-route>
+
+	<default caps="100"/>
+
+	<start name="timer">
+		<resource name="CPU" quantum="10"/>
+		<resource name="RAM" quantum="1M"/>
+		<provides><service name="Timer"/></provides>
+	</start>
+
+	<start name="vfs">
+		<resource name="RAM" quantum="2M"/>
+		<provides><service name="File_system"/></provides>
+		<config>
+			<vfs>
+				<!-- be careful to avoid endless output loop for core.log -->
+				<dir name="log_core"> <} [log_service] { name="log.log"/> </dir>
+			</vfs>
+			<policy label_prefix="fs_log" writeable="yes"/>
+		</config>
+	</start>
+
+	<start name="fs_log">
+		<resource name="RAM" quantum="2M"/>
+		<provides><service name="LOG"/></provides>
+		<config>
+			<policy label="log_core -> log"/>
+		</config>
+		<route>
+			<service name="File_system"> <child name="vfs"/> </service>
+			<any-service> <parent/> </any-service>
+		</route>
+	</start>
+
+	<start name="log_core">
+		<resource name="RAM" quantum="10M"/>
+		<config period_ms="2000"/>
+		<route>
+			<service name="ROM" unscoped_label="log_core"> <parent/> </service>
+			<service name="ROM" unscoped_label="ld.lib.so"> <parent/> </service>
+			<service name="ROM" label="log"> <parent label="core_log"/> </service>
+			<service name="Timer"> <child name="timer"/> </service>
+			<service name="LOG" label="log"> <child name="fs_log"/> </service>
+			<service name="PD"> <parent/> </service>
+			<service name="CPU"> <parent/> </service>
+			<service name="LOG"> <parent/> </service>
+		</route>
+	</start>
+</config>
+}
+
+build_boot_image "core init timer ld.lib.so vfs fs_log log_core"
+
+append qemu_args " -nographic "
+
+if { [get_cmd_switch --autopilot] } {
+	run_genode_until {.*\[init -> vfs] \[.*\n} 20
+} else {
+	run_genode_until forever
+}

repos/os/src/app/log_core/component.cc

@@ -0,0 +1,126 @@
+/*
+ * \brief  Component transforming core and kernel output to Genode LOG output
+ * \author Alexander Boettcher
+ * \date   2016-12-22
+ */
+
+/*
+ * Copyright (C) 2016-2017 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU Affero General Public License version 3.
+ */
+
+/* base includes */
+#include <base/component.h>
+#include <log_session/connection.h>
+
+/* os includes */
+#include <base/attached_rom_dataspace.h>
+#include <timer_session/connection.h>
+
+
+class Log
+{
+	private:
+
+		Genode::Attached_rom_dataspace _rom_ds;
+		Genode::Log_connection         _log;
+
+		char           _buffer [Genode::Log_session::MAX_STRING_LEN + 1];
+		unsigned short _buf_pos { 0 };
+		unsigned       _rom_pos { 0 };
+
+		unsigned log_size() const { return _rom_ds.size() - sizeof(_rom_pos); }
+
+		char const * char_from_rom(unsigned offset = 0) const
+		{
+			return _rom_ds.local_addr<char const>() + sizeof(_rom_pos) +
+			       (_rom_pos + offset) % log_size();
+		}
+
+		unsigned next_pos(unsigned pos) const {
+			return (pos + 1) % log_size(); }
+
+		unsigned end_pos() const {
+			return *_rom_ds.local_addr<unsigned volatile>() % log_size(); }
+
+		void _rom_to_log(unsigned const last_pos)
+		{
+			unsigned up_to_pos = last_pos;
+
+			for (; _rom_pos != next_pos(up_to_pos)
+				 ; _rom_pos = next_pos(_rom_pos), up_to_pos = end_pos()) {
+
+				char const c = *char_from_rom();
+
+				_buffer[_buf_pos++] = c;
+
+				if (_buf_pos + 1U < sizeof(_buffer) && c != '\n')
+					continue;
+
+				_buffer[_buf_pos] = 0;
+				_log.write(Genode::Log_session::String(_buffer));
+				_buf_pos = 0;
+			}
+		}
+
+	public:
+
+		Log (Genode::Env &env, char const * const rom_name,
+		     char const * const log_name)
+		: _rom_ds(env, rom_name), _log(env, log_name)
+		{
+			unsigned const pos = end_pos();
+
+			/* initial check whether already log wrapped at least one time */
+			enum { COUNT_TO_CHECK_FOR_WRAP = 8 };
+			for (unsigned i = 1; i <= COUNT_TO_CHECK_FOR_WRAP; i++) {
+				if (*char_from_rom(pos + i) == 0)
+					continue;
+
+				/* wrap detected, set pos behind last known pos */
+				_rom_pos = next_pos(pos + 1) % log_size();
+				break;
+			}
+
+			_rom_to_log(pos);
+		}
+
+		void log() { _rom_to_log(end_pos()); }
+};
+
+struct Monitor
+{
+	Genode::Env &env;
+
+	Log output { env, "log", "log" };
+
+	Timer::Connection timer { env };
+
+	Genode::Signal_handler<Monitor> interval { env.ep(), *this, &Monitor::check };
+
+	Monitor(Genode::Env &env) : env(env)
+	{
+		timer.sigh(interval);
+
+		Genode::addr_t period_ms = 1000;
+
+		try {
+			Genode::Attached_rom_dataspace config { env, "config" };
+			period_ms = config.xml().attribute_value("period_ms", 1000UL);
+		} catch (...) { }
+
+		Genode::log("update every ", period_ms," ms");
+
+		timer.trigger_periodic(1000UL * period_ms);
+	}
+
+	void check()
+	{
+		output.log();
+	}
+};
+
+
+void Component::construct(Genode::Env &env) { static Monitor output(env); }

repos/os/src/app/log_core/target.mk

@@ -0,0 +1,3 @@
+TARGET = log_core
+SRC_CC = component.cc
+LIBS   = base

tool/autopilot.list

@@ -105,3 +105,4 @@ nic_dump
 slab
 ada
 fs_report
+log_core