Initial support for multiple UIs

Move the device discovery code from separate udev helpers to a single
process to listen on two sockets: one SOCK_DGRAM for incoming udev
events, and one SOCK_STREAM for UIs to connect.

Initial support for client/server infrastructure, still need to wire-up
the udev messages.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

22 files changed, 2772 insertions, 0 deletions

diff --git a/discover/discover-server.c b/discover/discover-server.c
new file mode 100644
index 0000000..8358f06
--- /dev/null
+++ b/discover/discover-server.c
@@ -0,0 +1,227 @@
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <errno.h>
+#include <assert.h>
+
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <asm/byteorder.h>
+
+#include <talloc/talloc.h>
+
+#include "ui/common/device.h"
+#include "pb-protocol/pb-protocol.h"
+#include "list/list.h"
+
+#include "log.h"
+#include "waiter.h"
+
+struct discover_server {
+	int socket;
+	struct waiter *waiter;
+	struct list clients;
+};
+
+struct client {
+	struct list_item list;
+	int fd;
+};
+
+
+static int server_destructor(void *arg)
+{
+	struct discover_server *server = arg;
+
+	if (server->waiter)
+		waiter_unregister(server->waiter);
+
+	if (server->socket >= 0)
+		close(server->socket);
+
+	return 0;
+}
+
+static int client_destructor(void *arg)
+{
+	struct client *client = arg;
+
+	if (client->fd >= 0)
+		close(client->fd);
+
+	list_remove(&client->list);
+
+	return 0;
+
+}
+
+static void print_clients(struct discover_server *server)
+	__attribute__((unused));
+
+static void print_clients(struct discover_server *server)
+{
+	struct client *client;
+
+	printf("current clients [%p,%p,%p]:\n",
+			&server->clients.head,
+			server->clients.head.prev,
+			server->clients.head.next);
+	list_for_each_entry(&server->clients, client, list)
+		printf("\t[%p,%p,%p] client: %d\n", &client->list,
+				client->list.prev, client->list.next,
+				client->fd);
+}
+
+static struct boot_option options[] = {
+	{
+		.id = "1.1",
+		.name = "meep one",
+		.description = "meep description one",
+		.icon_file = "meep.one.png",
+		.boot_args = "root=/dev/sda1",
+	},
+};
+
+static struct device device = {
+	.id = "1",
+	.name = "meep",
+	.description = "meep description",
+	.icon_file = "meep.png",
+	.n_options = 1,
+	.options = options,
+};
+
+static int client_write_message(struct discover_server *server,
+		struct client *client, struct pb_protocol_message *message)
+{
+	int rc;
+
+	rc = pb_protocol_write_message(client->fd, message);
+	if (rc)
+		talloc_free(client);
+
+	return rc;
+}
+
+static int write_add_message(struct discover_server *server,
+		struct client *client, struct device *dev)
+{
+	struct pb_protocol_message *message;
+	int len;
+
+	len = pb_protocol_device_len(dev);
+
+	message = pb_protocol_create_message(client,
+			PB_PROTOCOL_ACTION_ADD, len);
+	if (!message)
+		return -1;
+
+	pb_protocol_serialise_device(dev, message->payload, len);
+
+	return client_write_message(server, client, message);
+}
+
+static int write_remove_message(struct discover_server *server,
+		struct client *client, char *dev_id)
+{
+	struct pb_protocol_message *message;
+	int len;
+
+	len = strlen(dev_id) + sizeof(uint32_t);
+
+	message = pb_protocol_create_message(client,
+			PB_PROTOCOL_ACTION_REMOVE, len);
+	if (!message)
+		return -1;
+
+	pb_protocol_serialise_string(message->payload, dev_id);
+
+	return client_write_message(server, client, message);
+}
+
+static int discover_server_process(void *arg)
+{
+	struct discover_server *server = arg;
+	struct client *client;
+	int fd;
+
+
+	len = sizeof(addr);
+
+	/* accept the incoming connection */
+	fd = accept(server->socket, NULL, 0);
+	if (!fd) {
+		pb_log("accept: %s\n", strerror(errno));
+		return 0;
+	}
+
+	/* add to our list of clients */
+	client = talloc(server, struct client);
+	list_add(&server->clients, &client->list);
+
+	talloc_set_destructor(client, client_destructor);
+
+	client->fd = fd;
+
+	/* send existing devices to client */
+	write_add_message(server, client, &device);
+
+	sleep(2);
+
+	write_remove_message(server, client, "1");
+
+	return 0;
+}
+
+struct discover_server *discover_server_init(void)
+{
+	struct discover_server *server;
+	struct sockaddr_un addr;
+
+	server = talloc(NULL, struct discover_server);
+	if (!server)
+		return NULL;
+
+	server->waiter = NULL;
+	list_init(&server->clients);
+
+	unlink(PB_SOCKET_PATH);
+
+	server->socket = socket(AF_UNIX, SOCK_STREAM, 0);
+	if (server->socket < 0) {
+		pb_log("error creating server socket: %s\n", strerror(errno));
+		goto out_err;
+	}
+
+	talloc_set_destructor(server, server_destructor);
+
+	addr.sun_family = AF_UNIX;
+	strcpy(addr.sun_path, PB_SOCKET_PATH);
+
+	if (bind(server->socket, (struct sockaddr *)&addr, sizeof(addr))) {
+		pb_log("error binding server socket: %s\n", strerror(errno));
+		goto out_err;
+	}
+
+	if (listen(server->socket, 8)) {
+		pb_log("server socket listen: %s\n", strerror(errno));
+		goto out_err;
+	}
+
+	server->waiter = waiter_register(server->socket, WAIT_IN,
+			discover_server_process, server);
+
+	return server;
+
+out_err:
+	talloc_free(server);
+	return NULL;
+}
+
+void discover_server_destroy(struct discover_server *server)
+{
+	talloc_free(server);
+}
+
diff --git a/discover/discover-server.h b/discover/discover-server.h
new file mode 100644
index 0000000..ff27f15
--- /dev/null
+++ b/discover/discover-server.h
@@ -0,0 +1,10 @@
+#ifndef _DISCOVER_SERVER_H
+#define _DISCOVER_SERVER_H
+
+struct discover_server;
+
+struct discover_server *discover_server_init(void);
+
+void discover_server_destroy(struct discover_server *server);
+
+#endif /* _DISCOVER_SERVER_H */
diff --git a/discover/kboot-parser.c b/discover/kboot-parser.c
new file mode 100644
index 0000000..df2e762
--- /dev/null
+++ b/discover/kboot-parser.c
@@ -0,0 +1,288 @@
+#define _GNU_SOURCE
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+#include <unistd.h>
+
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include "parser.h"
+#include "params.h"
+
+#define buf_size 1024
+
+static const char *devpath;
+
+static int param_is_ignored(const char *param)
+{
+	static const char *ignored_options[] =
+		{ "message", "timeout", "default", NULL };
+	const char **str;
+
+	for (str = ignored_options; *str; str++)
+		if (streq(*str, param))
+			return 1;
+	return 0;
+}
+
+/**
+ * Splits a name=value pair, with value terminated by @term (or nul). if there
+ * is no '=', then only the value is populated, and *name is set to NULL. The
+ * string is modified in place.
+ *
+ * Returns the next byte to process, or null if we've hit the end of the
+ * string.
+ *
+ * */
+static char *get_param_pair(char *str, char **name_out, char **value_out,
+		char terminator)
+{
+	char *sep, *tmp, *name, *value;
+
+	/* terminate the value */
+	tmp = strchr(str, terminator);
+	if (tmp)
+		*tmp = 0;
+	else
+		tmp = NULL;
+
+	sep = strchr(str, '=');
+	if (!sep) {
+		*name_out = NULL;
+		*value_out = str;
+		return tmp ? tmp + 1 : NULL;
+	}
+
+	/* terminate the name */
+	*sep = 0;
+
+	/* remove leading spaces */
+	for (name = str; isspace(*name); name++);
+	for (value = sep + 1; isspace(*value); value++);
+
+	/* .. and trailing ones.. */
+	for (sep--; isspace(*sep); sep--)
+		*sep = 0;
+	for (sep = value + strlen(value) - 1; isspace(*sep); sep--)
+		*sep = 0;
+
+	*name_out = name;
+	*value_out = value;
+
+	return tmp ? tmp + 1 : NULL;
+}
+
+struct global_option {
+	char *name;
+	char *value;
+};
+
+
+static struct global_option global_options[] = {
+	{ .name = "root" },
+	{ .name = "initrd" },
+	{ .name = "video" },
+	{ .name = NULL }
+};
+
+/*
+ * Check if an option (name=value) is a global option. If so, store it in
+ * the global options table, and return 1. Otherwise, return 0.
+ */
+static int check_for_global_option(const char *name, const char *value)
+{
+	int i;
+
+	for (i = 0; global_options[i].name ;i++) {
+		if (!strcmp(name, global_options[i].name)) {
+			global_options[i].value = strdup(value);
+			return 1;
+		}
+	}
+	return 0;
+}
+
+static char *get_global_option(const char *name)
+{
+	int i;
+
+	for (i = 0; global_options[i].name ;i++)
+		if (!strcmp(name, global_options[i].name))
+			return global_options[i].value;
+
+	return NULL;
+}
+
+static int parse_option(struct boot_option *opt, char *config)
+{
+	char *pos, *name, *value, *root, *initrd, *cmdline, *tmp;
+
+	root = initrd = cmdline = NULL;
+
+	/* remove quotes around the value */
+	while (*config == '"' || *config == '\'')
+		config++;
+
+	pos = config + strlen(config) - 1;
+	while (*pos == '"' || *pos == '\'')
+		*(pos--) = 0;
+
+	if (!strlen(pos))
+		return 0;
+
+	pos = strchr(config, ' ');
+
+	/* if there's no space, it's only a kernel image with no params */
+	if (!pos) {
+		opt->boot_image_file = resolve_path(config, devpath);
+		opt->description = strdup(config);
+		return 1;
+	}
+
+	*pos = 0;
+	opt->boot_image_file = resolve_path(config, devpath);
+
+	cmdline = malloc(buf_size);
+	*cmdline = 0;
+
+	for (pos++; pos;) {
+		pos = get_param_pair(pos, &name, &value, ' ');
+
+		if (!name) {
+			strcat(cmdline, " ");
+			strcat(cmdline, value);
+
+		} else if (streq(name, "initrd")) {
+			initrd = value;
+
+		} else if (streq(name, "root")) {
+			root = value;
+
+		} else {
+			strcat(cmdline, " ");
+			*(value - 1) = '=';
+			strcat(cmdline, name);
+		}
+	}
+
+	if (!root)
+		root = get_global_option("root");
+	if (!initrd)
+		initrd = get_global_option("initrd");
+
+	if (initrd) {
+		asprintf(&tmp, "initrd=%s %s", initrd, cmdline);
+		free(cmdline);
+		cmdline = tmp;
+
+		opt->initrd_file = resolve_path(initrd, devpath);
+	}
+
+	if (root) {
+		asprintf(&tmp, "root=%s %s", root, cmdline);
+		free(cmdline);
+		cmdline = tmp;
+
+	} else if (initrd) {
+		/* if there's an initrd but no root, fake up /dev/ram0 */
+		asprintf(&tmp, "root=/dev/ram0 %s", cmdline);
+		free(cmdline);
+		cmdline = tmp;
+	}
+
+	pb_log("kboot cmdline: %s\n", cmdline);
+	opt->boot_args = cmdline;
+
+	asprintf(&opt->description, "%s %s",
+			config, opt->boot_args);
+
+	return 1;
+}
+
+static void parse_buf(struct device *dev, char *buf)
+{
+	char *pos, *name, *value;
+	int sent_device = 0;
+
+	for (pos = buf; pos;) {
+		struct boot_option opt;
+
+		pos = get_param_pair(pos, &name, &value, '\n');
+
+		pb_log("kboot param: '%s' = '%s'\n", name, value);
+
+		if (name == NULL || param_is_ignored(name))
+			continue;
+
+		if (*name == '#')
+			continue;
+
+		if (check_for_global_option(name, value))
+			continue;
+
+		memset(&opt, 0, sizeof(opt));
+		opt.name = strdup(name);
+
+		if (parse_option(&opt, value))
+			if (!sent_device++)
+				add_device(dev);
+			add_boot_option(&opt);
+
+		free(opt.name);
+	}
+}
+
+static int parse(const char *device)
+{
+	char *filepath, *buf;
+	int fd, len, rc = 0;
+	struct stat stat;
+	struct device *dev;
+
+	devpath = device;
+
+	filepath = resolve_path("/etc/kboot.conf", devpath);
+
+	fd = open(filepath, O_RDONLY);
+	if (fd < 0)
+		goto out_free_path;
+
+	if (fstat(fd, &stat))
+		goto out_close;
+
+	buf = malloc(stat.st_size + 1);
+	if (!buf)
+		goto out_close;;
+
+	len = read(fd, buf, stat.st_size);
+	if (len < 0)
+		goto out_free_buf;
+	buf[len] = 0;
+
+	dev = malloc(sizeof(*dev));
+	memset(dev, 0, sizeof(*dev));
+	dev->id = strdup(device);
+	dev->icon_file = strdup(generic_icon_file(guess_device_type()));
+
+	parse_buf(dev, buf);
+
+	rc = 1;
+
+out_free_buf:
+	free(buf);
+out_close:
+	close(fd);
+out_free_path:
+	free(filepath);
+	return rc;
+}
+
+struct parser kboot_parser = {
+	.name = "kboot.conf parser",
+	.priority = 98,
+	.parse	  = parse
+};
diff --git a/discover/log.c b/discover/log.c
new file mode 100644
index 0000000..189f31e
--- /dev/null
+++ b/discover/log.c
@@ -0,0 +1,24 @@
+
+#include <stdarg.h>
+#include <stdio.h>
+
+#include "log.h"
+
+static FILE *logf;
+
+void pb_log(const char *fmt, ...)
+{
+	va_list ap;
+	FILE *stream;
+
+	stream = logf ? logf : stdout;
+
+	va_start(ap, fmt);
+	vfprintf(stream, fmt, ap);
+	va_end(ap);
+}
+
+void pb_log_set_stream(FILE *stream)
+{
+	logf = stream;
+}
diff --git a/discover/log.h b/discover/log.h
new file mode 100644
index 0000000..7f9b01f
--- /dev/null
+++ b/discover/log.h
@@ -0,0 +1,6 @@
+#ifndef _LOG_H
+#define _LOG_H
+
+void pb_log(const char *fmt, ...);
+
+#endif /* _LOG_H */
diff --git a/discover/message.h b/discover/message.h
new file mode 100644
index 0000000..d0b0e34
--- /dev/null
+++ b/discover/message.h
@@ -0,0 +1,31 @@
+
+#ifndef _MESSAGE_H
+#define _MESSAGE_H
+
+enum device_action {
+	DEV_ACTION_ADD_DEVICE = 0,
+	DEV_ACTION_ADD_OPTION = 1,
+	DEV_ACTION_REMOVE_DEVICE = 2,
+	DEV_ACTION_REMOVE_OPTION = 3
+};
+
+struct device {
+	char *id;
+	char *name;
+	char *description;
+	char *icon_file;
+
+	struct boot_option {
+		char *id;
+		char *name;
+		char *description;
+		char *icon_file;
+		char *boot_image_file;
+		char *initrd_file;
+		char *boot_args;
+	} *options;
+	int n_options;
+};
+
+
+#endif /* _MESSAGE_H */
diff --git a/discover/native-parser.c b/discover/native-parser.c
new file mode 100644
index 0000000..24713b1
--- /dev/null
+++ b/discover/native-parser.c
@@ -0,0 +1,124 @@
+
+#include "parser.h"
+#include "params.h"
+#include "paths.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+const char *conf_filename = "/boot/petitboot.conf";
+
+static struct boot_option *cur_opt;
+static struct device *dev;
+static const char *devpath;
+int device_added;
+
+int check_and_add_device(struct device *dev)
+{
+	if (!dev->icon_file)
+		dev->icon_file = strdup(generic_icon_file(guess_device_type()));
+
+	return !add_device(dev);
+}
+
+static int section(char *section_name)
+{
+	if (!device_added++ && !check_and_add_device(dev))
+		return 0;
+
+	if (cur_opt) {
+		add_boot_option(cur_opt);
+		free_boot_option(cur_opt);
+	}
+
+	cur_opt = malloc(sizeof(*cur_opt));
+	memset(cur_opt, 0, sizeof(*cur_opt));
+	return 1;
+}
+
+
+static void set_boot_option_parameter(struct boot_option *opt,
+		const char *name, const char *value)
+{
+	if (streq(name, "name"))
+		opt->name = strdup(value);
+
+	else if (streq(name, "description"))
+		opt->description = strdup(value);
+
+	else if (streq(name, "image"))
+		opt->boot_image_file = resolve_path(value, devpath);
+
+	else if (streq(name, "icon"))
+		opt->icon_file = resolve_path(value, devpath);
+
+	else if (streq(name, "initrd"))
+		opt->initrd_file =resolve_path(value, devpath);
+
+	else if (streq(name, "args"))
+		opt->boot_args = strdup(value);
+
+	else
+		fprintf(stderr, "Unknown parameter %s\n", name);
+}
+
+static void set_device_parameter(struct device *dev,
+		const char *name, const char *value)
+{
+	if (streq(name, "name"))
+		dev->name = strdup(value);
+
+	else if (streq(name, "description"))
+		dev->description = strdup(value);
+
+	else if (streq(name, "icon"))
+		dev->icon_file = resolve_path(value, devpath);
+}
+
+static int parameter(char *param_name, char *param_value)
+{
+	if (cur_opt)
+		set_boot_option_parameter(cur_opt, param_name, param_value);
+	else
+		set_device_parameter(dev, param_name, param_value);
+	return 1;
+}
+
+
+int parse(const char *device)
+{
+	char *filepath;
+	int rc;
+
+	filepath = resolve_path(conf_filename, device);
+
+	cur_opt = NULL;
+	dev = malloc(sizeof(*dev));
+	memset(dev, 0, sizeof(*dev));
+	dev->id = strdup(device);
+
+	rc = pm_process(filepath, section, parameter);
+	if (!rc)
+		return 0;
+
+	if (cur_opt) {
+		add_boot_option(cur_opt);
+		free_boot_option(cur_opt);
+	}
+
+	cur_opt = NULL;
+
+	free(filepath);
+
+	return 1;
+}
+
+struct parser native_parser = {
+	.name = "native petitboot parser",
+	.priority = 100,
+	.parse	  = parse
+};
+
+
+
diff --git a/discover/params.c b/discover/params.c
new file mode 100644
index 0000000..76a1451
--- /dev/null
+++ b/discover/params.c
@@ -0,0 +1,595 @@
+/* This modules is based on the params.c module from Samba, written by Karl Auer
+   and much modifed by Christopher Hertel. */
+
+/*
+ * 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 Street - Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <ctype.h>
+#include <errno.h>
+
+#include "params.h"
+
+#define new_array(type, num) ((type *)_new_array(sizeof(type), (num)))
+#define realloc_array(ptr, type, num) \
+	((type *)_realloc_array((ptr), sizeof(type), (num)))
+
+#define rprintf(x, ...) do { fprintf(stderr, ##__VA_ARGS__);	\
+				fprintf(stderr, "\n"); } while (0)
+#define rsyserr(x, y, ...) do { fprintf(stderr, ##__VA_ARGS__);	\
+				fprintf(stderr, "\n"); } while (0)
+
+#define MALLOC_MAX 0x40000000
+#define False 0
+#define True 1
+
+void *_new_array(unsigned int size, unsigned long num)
+{
+	if (num >= MALLOC_MAX/size)
+		return NULL;
+	return malloc(size * num);
+}
+
+void *_realloc_array(void *ptr, unsigned int size, unsigned long num)
+{
+	if (num >= MALLOC_MAX/size)
+		return NULL;
+	/* No realloc should need this, but just in case... */
+	if (!ptr)
+		return malloc(size * num);
+	return realloc(ptr, size * num);
+}
+
+
+/* -------------------------------------------------------------------------- **
+ *
+ * Module name: params
+ *
+ * -------------------------------------------------------------------------- **
+ *
+ *  This module performs lexical analysis and initial parsing of a
+ *  Windows-like parameter file.  It recognizes and handles four token
+ *  types:  section-name, parameter-name, parameter-value, and
+ *  end-of-file.  Comments and line continuation are handled
+ *  internally.
+ *
+ *  The entry point to the module is function pm_process().  This
+ *  function opens the source file, calls the Parse() function to parse
+ *  the input, and then closes the file when either the EOF is reached
+ *  or a fatal error is encountered.
+ *
+ *  A sample parameter file might look like this:
+ *
+ *  [section one]
+ *  parameter one = value string
+ *  parameter two = another value
+ *  [section two]
+ *  new parameter = some value or t'other
+ *
+ *  The parameter file is divided into sections by section headers:
+ *  section names enclosed in square brackets (eg. [section one]).
+ *  Each section contains parameter lines, each of which consist of a
+ *  parameter name and value delimited by an equal sign.  Roughly, the
+ *  syntax is:
+ *
+ *    <file>            :==  { <section> } EOF
+ *
+ *    <section>         :==  <section header> { <parameter line> }
+ *
+ *    <section header>  :==  '[' NAME ']'
+ *
+ *    <parameter line>  :==  NAME '=' VALUE '\n'
+ *
+ *  Blank lines and comment lines are ignored.  Comment lines are lines
+ *  beginning with either a semicolon (';') or a pound sign ('#').
+ *
+ *  All whitespace in section names and parameter names is compressed
+ *  to single spaces.  Leading and trailing whitespace is stipped from
+ *  both names and values.
+ *
+ *  Only the first equals sign in a parameter line is significant.
+ *  Parameter values may contain equals signs, square brackets and
+ *  semicolons.  Internal whitespace is retained in parameter values,
+ *  with the exception of the '\r' character, which is stripped for
+ *  historic reasons.  Parameter names may not start with a left square
+ *  bracket, an equal sign, a pound sign, or a semicolon, because these
+ *  are used to identify other tokens.
+ *
+ * -------------------------------------------------------------------------- **
+ */
+
+/* -------------------------------------------------------------------------- **
+ * Constants...
+ */
+
+#define BUFR_INC 1024
+
+
+/* -------------------------------------------------------------------------- **
+ * Variables...
+ *
+ *  bufr        - pointer to a global buffer.  This is probably a kludge,
+ *                but it was the nicest kludge I could think of (for now).
+ *  bSize       - The size of the global buffer <bufr>.
+ */
+
+static char *bufr  = NULL;
+static int   bSize = 0;
+
+/* -------------------------------------------------------------------------- **
+ * Functions...
+ */
+
+static int EatWhitespace( FILE *InFile )
+  /* ------------------------------------------------------------------------ **
+   * Scan past whitespace (see ctype(3C)) and return the first non-whitespace
+   * character, or newline, or EOF.
+   *
+   *  Input:  InFile  - Input source.
+   *
+   *  Output: The next non-whitespace character in the input stream.
+   *
+   *  Notes:  Because the config files use a line-oriented grammar, we
+   *          explicitly exclude the newline character from the list of
+   *          whitespace characters.
+   *        - Note that both EOF (-1) and the nul character ('\0') are
+   *          considered end-of-file markers.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  int c;
+
+  for( c = getc( InFile ); isspace( c ) && ('\n' != c); c = getc( InFile ) )
+    ;
+  return( c );
+  } /* EatWhitespace */
+
+static int EatComment( FILE *InFile )
+  /* ------------------------------------------------------------------------ **
+   * Scan to the end of a comment.
+   *
+   *  Input:  InFile  - Input source.
+   *
+   *  Output: The character that marks the end of the comment.  Normally,
+   *          this will be a newline, but it *might* be an EOF.
+   *
+   *  Notes:  Because the config files use a line-oriented grammar, we
+   *          explicitly exclude the newline character from the list of
+   *          whitespace characters.
+   *        - Note that both EOF (-1) and the nul character ('\0') are
+   *          considered end-of-file markers.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  int c;
+
+  for( c = getc( InFile ); ('\n'!=c) && (EOF!=c) && (c>0); c = getc( InFile ) )
+    ;
+  return( c );
+  } /* EatComment */
+
+static int Continuation( char *line, int pos )
+  /* ------------------------------------------------------------------------ **
+   * Scan backards within a string to discover if the last non-whitespace
+   * character is a line-continuation character ('\\').
+   *
+   *  Input:  line  - A pointer to a buffer containing the string to be
+   *                  scanned.
+   *          pos   - This is taken to be the offset of the end of the
+   *                  string.  This position is *not* scanned.
+   *
+   *  Output: The offset of the '\\' character if it was found, or -1 to
+   *          indicate that it was not.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  pos--;
+  while( (pos >= 0) && isspace(((unsigned char *)line)[pos]) )
+     pos--;
+
+  return( ((pos >= 0) && ('\\' == line[pos])) ? pos : -1 );
+  } /* Continuation */
+
+
+static BOOL Section( FILE *InFile, BOOL (*sfunc)(char *) )
+  /* ------------------------------------------------------------------------ **
+   * Scan a section name, and pass the name to function sfunc().
+   *
+   *  Input:  InFile  - Input source.
+   *          sfunc   - Pointer to the function to be called if the section
+   *                    name is successfully read.
+   *
+   *  Output: True if the section name was read and True was returned from
+   *          <sfunc>.  False if <sfunc> failed or if a lexical error was
+   *          encountered.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  int   c;
+  int   i;
+  int   end;
+  char *func  = "params.c:Section() -";
+
+  i = 0;      /* <i> is the offset of the next free byte in bufr[] and  */
+  end = 0;    /* <end> is the current "end of string" offset.  In most  */
+              /* cases these will be the same, but if the last          */
+              /* character written to bufr[] is a space, then <end>     */
+              /* will be one less than <i>.                             */
+
+  c = EatWhitespace( InFile );    /* We've already got the '['.  Scan */
+                                  /* past initial white space.        */
+
+  while( (EOF != c) && (c > 0) )
+    {
+
+    /* Check that the buffer is big enough for the next character. */
+    if( i > (bSize - 2) )
+      {
+      bSize += BUFR_INC;
+      bufr   = realloc_array( bufr, char, bSize );
+      if( NULL == bufr )
+        {
+        rprintf(FERROR, "%s Memory re-allocation failure.", func);
+        return( False );
+        }
+      }
+
+    /* Handle a single character. */
+    switch( c )
+      {
+      case ']':                       /* Found the closing bracket.         */
+        bufr[end] = '\0';
+        if( 0 == end )                  /* Don't allow an empty name.       */
+          {
+          rprintf(FERROR, "%s Empty section name in configuration file.\n", func );
+          return( False );
+          }
+        if( !sfunc( bufr ) )            /* Got a valid name.  Deal with it. */
+          return( False );
+        (void)EatComment( InFile );     /* Finish off the line.             */
+        return( True );
+
+      case '\n':                      /* Got newline before closing ']'.    */
+        i = Continuation( bufr, i );    /* Check for line continuation.     */
+        if( i < 0 )
+          {
+          bufr[end] = '\0';
+          rprintf(FERROR, "%s Badly formed line in configuration file: %s\n",
+                   func, bufr );
+          return( False );
+          }
+        end = ( (i > 0) && (' ' == bufr[i - 1]) ) ? (i - 1) : (i);
+        c = getc( InFile );             /* Continue with next line.         */
+        break;
+
+      default:                        /* All else are a valid name chars.   */
+        if( isspace( c ) )              /* One space per whitespace region. */
+          {
+          bufr[end] = ' ';
+          i = end + 1;
+          c = EatWhitespace( InFile );
+          }
+        else                            /* All others copy verbatim.        */
+          {
+          bufr[i++] = c;
+          end = i;
+          c = getc( InFile );
+          }
+      }
+    }
+
+  /* We arrive here if we've met the EOF before the closing bracket. */
+  rprintf(FERROR, "%s Unexpected EOF in the configuration file: %s\n", func, bufr );
+  return( False );
+  } /* Section */
+
+static BOOL Parameter( FILE *InFile, BOOL (*pfunc)(char *, char *), int c )
+  /* ------------------------------------------------------------------------ **
+   * Scan a parameter name and value, and pass these two fields to pfunc().
+   *
+   *  Input:  InFile  - The input source.
+   *          pfunc   - A pointer to the function that will be called to
+   *                    process the parameter, once it has been scanned.
+   *          c       - The first character of the parameter name, which
+   *                    would have been read by Parse().  Unlike a comment
+   *                    line or a section header, there is no lead-in
+   *                    character that can be discarded.
+   *
+   *  Output: True if the parameter name and value were scanned and processed
+   *          successfully, else False.
+   *
+   *  Notes:  This function is in two parts.  The first loop scans the
+   *          parameter name.  Internal whitespace is compressed, and an
+   *          equal sign (=) terminates the token.  Leading and trailing
+   *          whitespace is discarded.  The second loop scans the parameter
+   *          value.  When both have been successfully identified, they are
+   *          passed to pfunc() for processing.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  int   i       = 0;    /* Position within bufr. */
+  int   end     = 0;    /* bufr[end] is current end-of-string. */
+  int   vstart  = 0;    /* Starting position of the parameter value. */
+  char *func    = "params.c:Parameter() -";
+
+  /* Read the parameter name. */
+  while( 0 == vstart )  /* Loop until we've found the start of the value. */
+    {
+
+    if( i > (bSize - 2) )       /* Ensure there's space for next char.    */
+      {
+      bSize += BUFR_INC;
+      bufr   = realloc_array( bufr, char, bSize );
+      if( NULL == bufr )
+        {
+        rprintf(FERROR, "%s Memory re-allocation failure.", func) ;
+        return( False );
+        }
+      }
+
+    switch( c )
+      {
+      case '=':                 /* Equal sign marks end of param name. */
+        if( 0 == end )              /* Don't allow an empty name.      */
+          {
+          rprintf(FERROR, "%s Invalid parameter name in config. file.\n", func );
+          return( False );
+          }
+        bufr[end++] = '\0';         /* Mark end of string & advance.   */
+        i       = end;              /* New string starts here.         */
+        vstart  = end;              /* New string is parameter value.  */
+        bufr[i] = '\0';             /* New string is nul, for now.     */
+        break;
+
+      case '\n':                /* Find continuation char, else error. */
+        i = Continuation( bufr, i );
+        if( i < 0 )
+          {
+          bufr[end] = '\0';
+          rprintf(FERROR, "%s Ignoring badly formed line in configuration file: %s\n",
+                   func, bufr );
+          return( True );
+          }
+        end = ( (i > 0) && (' ' == bufr[i - 1]) ) ? (i - 1) : (i);
+        c = getc( InFile );       /* Read past eoln.                   */
+        break;
+
+      case '\0':                /* Shouldn't have EOF within param name. */
+      case EOF:
+        bufr[i] = '\0';
+        rprintf(FERROR, "%s Unexpected end-of-file at: %s\n", func, bufr );
+        return( True );
+
+      default:
+        if( isspace( c ) )     /* One ' ' per whitespace region.       */
+          {
+          bufr[end] = ' ';
+          i = end + 1;
+          c = EatWhitespace( InFile );
+          }
+        else                   /* All others verbatim.                 */
+          {
+          bufr[i++] = c;
+          end = i;
+          c = getc( InFile );
+          }
+      }
+    }
+
+  /* Now parse the value. */
+  c = EatWhitespace( InFile );  /* Again, trim leading whitespace. */
+  while( (EOF !=c) && (c > 0) )
+    {
+
+    if( i > (bSize - 2) )       /* Make sure there's enough room. */
+      {
+      bSize += BUFR_INC;
+      bufr   = realloc_array( bufr, char, bSize );
+      if( NULL == bufr )
+        {
+        rprintf(FERROR, "%s Memory re-allocation failure.", func) ;
+        return( False );
+        }
+      }
+
+    switch( c )
+      {
+      case '\r':              /* Explicitly remove '\r' because the older */
+        c = getc( InFile );   /* version called fgets_slash() which also  */
+        break;                /* removes them.                            */
+
+      case '\n':              /* Marks end of value unless there's a '\'. */
+        i = Continuation( bufr, i );
+        if( i < 0 )
+          c = 0;
+        else
+          {
+          for( end = i; (end >= 0) && isspace(((unsigned char *) bufr)[end]); end-- )
+            ;
+          c = getc( InFile );
+          }
+        break;
+
+      default:               /* All others verbatim.  Note that spaces do */
+        bufr[i++] = c;       /* not advance <end>.  This allows trimming  */
+        if( !isspace( c ) )  /* of whitespace at the end of the line.     */
+          end = i;
+        c = getc( InFile );
+        break;
+      }
+    }
+  bufr[end] = '\0';          /* End of value. */
+
+  return( pfunc( bufr, &bufr[vstart] ) );   /* Pass name & value to pfunc().  */
+  } /* Parameter */
+
+static BOOL Parse( FILE *InFile,
+                   BOOL (*sfunc)(char *),
+                   BOOL (*pfunc)(char *, char *) )
+  /* ------------------------------------------------------------------------ **
+   * Scan & parse the input.
+   *
+   *  Input:  InFile  - Input source.
+   *          sfunc   - Function to be called when a section name is scanned.
+   *                    See Section().
+   *          pfunc   - Function to be called when a parameter is scanned.
+   *                    See Parameter().
+   *
+   *  Output: True if the file was successfully scanned, else False.
+   *
+   *  Notes:  The input can be viewed in terms of 'lines'.  There are four
+   *          types of lines:
+   *            Blank      - May contain whitespace, otherwise empty.
+   *            Comment    - First non-whitespace character is a ';' or '#'.
+   *                         The remainder of the line is ignored.
+   *            Section    - First non-whitespace character is a '['.
+   *            Parameter  - The default case.
+   * 
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  int    c;
+
+  c = EatWhitespace( InFile );
+  while( (EOF != c) && (c > 0) )
+    {
+    switch( c )
+      {
+      case '\n':                        /* Blank line. */
+        c = EatWhitespace( InFile );
+        break;
+
+      case ';':                         /* Comment line. */
+      case '#':
+        c = EatComment( InFile );
+        break;
+
+      case '[':                         /* Section Header. */
+	      if (!sfunc) return True;
+	      if( !Section( InFile, sfunc ) )
+		      return( False );
+	      c = EatWhitespace( InFile );
+	      break;
+
+      case '\\':                        /* Bogus backslash. */
+        c = EatWhitespace( InFile );
+        break;
+
+      default:                          /* Parameter line. */
+        if( !Parameter( InFile, pfunc, c ) )
+          return( False );
+        c = EatWhitespace( InFile );
+        break;
+      }
+    }
+  return( True );
+  } /* Parse */
+
+static FILE *OpenConfFile( char *FileName )
+  /* ------------------------------------------------------------------------ **
+   * Open a configuration file.
+   *
+   *  Input:  FileName  - The pathname of the config file to be opened.
+   *
+   *  Output: A pointer of type (FILE *) to the opened file, or NULL if the
+   *          file could not be opened.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  FILE *OpenedFile;
+  char *func = "params.c:OpenConfFile() -";
+
+  if( NULL == FileName || 0 == *FileName )
+    {
+    rprintf(FERROR,"%s No configuration filename specified.\n", func);
+    return( NULL );
+    }
+
+  OpenedFile = fopen( FileName, "r" );
+  if( NULL == OpenedFile )
+    {
+    rsyserr(FERROR, errno, "unable to open configuration file \"%s\"",
+	    FileName);
+    }
+
+  return( OpenedFile );
+  } /* OpenConfFile */
+
+BOOL pm_process( char *FileName,
+                 BOOL (*sfunc)(char *),
+                 BOOL (*pfunc)(char *, char *) )
+  /* ------------------------------------------------------------------------ **
+   * Process the named parameter file.
+   *
+   *  Input:  FileName  - The pathname of the parameter file to be opened.
+   *          sfunc     - A pointer to a function that will be called when
+   *                      a section name is discovered.
+   *          pfunc     - A pointer to a function that will be called when
+   *                      a parameter name and value are discovered.
+   *
+   *  Output: TRUE if the file was successfully parsed, else FALSE.
+   *
+   * ------------------------------------------------------------------------ **
+   */
+  {
+  int   result;
+  FILE *InFile;
+  char *func = "params.c:pm_process() -";
+
+  InFile = OpenConfFile( FileName );          /* Open the config file. */
+  if( NULL == InFile )
+    return( False );
+
+  if( NULL != bufr )                          /* If we already have a buffer */
+    result = Parse( InFile, sfunc, pfunc );   /* (recursive call), then just */
+                                              /* use it.                     */
+
+  else                                        /* If we don't have a buffer   */
+    {                                         /* allocate one, then parse,   */
+    bSize = BUFR_INC;                         /* then free.                  */
+    bufr = new_array( char, bSize );
+    if( NULL == bufr )
+      {
+      rprintf(FERROR,"%s memory allocation failure.\n", func);
+      fclose(InFile);
+      return( False );
+      }
+    result = Parse( InFile, sfunc, pfunc );
+    free( bufr );
+    bufr  = NULL;
+    bSize = 0;
+    }
+
+  fclose(InFile);
+
+  if( !result )                               /* Generic failure. */
+    {
+    rprintf(FERROR,"%s Failed.  Error returned from params.c:parse().\n", func);
+    return( False );
+    }
+
+  return( True );                             /* Generic success. */
+  } /* pm_process */
+
+/* -------------------------------------------------------------------------- */
+
diff --git a/discover/params.h b/discover/params.h
new file mode 100644
index 0000000..02a39c9
--- /dev/null
+++ b/discover/params.h
@@ -0,0 +1,6 @@
+
+#define BOOL int
+
+BOOL pm_process( char *FileName,
+                 BOOL (*sfunc)(char *),
+                 BOOL (*pfunc)(char *, char *) );
diff --git a/discover/parser.c b/discover/parser.c
new file mode 100644
index 0000000..5e50dcb
--- /dev/null
+++ b/discover/parser.c
@@ -0,0 +1,85 @@
+
+#include <petitboot-paths.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "parser.h"
+
+extern struct parser native_parser;
+extern struct parser yaboot_parser;
+extern struct parser kboot_parser;
+
+/* array of parsers, ordered by priority */
+static struct parser *parsers[] = {
+	&native_parser,
+	&yaboot_parser,
+	&kboot_parser,
+	NULL
+};
+
+void iterate_parsers(const char *devpath, const char *mountpoint)
+{
+	int i;
+
+	pb_log("trying parsers for %s\n", devpath);
+
+	for (i = 0; parsers[i]; i++) {
+		pb_log("\ttrying parser '%s'\n", parsers[i]->name);
+		/* just use a dummy device path for now */
+		if (parsers[i]->parse(devpath))
+			return;
+	}
+	pb_log("\tno boot_options found\n");
+}
+
+/* convenience functions for parsers */
+void free_device(struct device *dev)
+{
+	if (!dev)
+		return;
+	if (dev->id)
+		free(dev->id);
+	if (dev->name)
+		free(dev->name);
+	if (dev->description)
+		free(dev->description);
+	if (dev->icon_file)
+		free(dev->icon_file);
+	free(dev);
+}
+
+void free_boot_option(struct boot_option *opt)
+{
+	if (!opt)
+		return;
+	if (opt->name)
+		free(opt->name);
+	if (opt->description)
+		free(opt->description);
+	if (opt->icon_file)
+		free(opt->icon_file);
+	if (opt->boot_image_file)
+		free(opt->boot_image_file);
+	if (opt->initrd_file)
+		free(opt->initrd_file);
+	if (opt->boot_args)
+		free(opt->boot_args);
+	free(opt);
+}
+
+const char *generic_icon_file(enum generic_icon_type type)
+{
+	switch (type) {
+	case ICON_TYPE_DISK:
+		return artwork_pathname("hdd.png");
+	case ICON_TYPE_USB:
+		return artwork_pathname("usbpen.png");
+	case ICON_TYPE_OPTICAL:
+		return artwork_pathname("cdrom.png");
+	case ICON_TYPE_NETWORK:
+	case ICON_TYPE_UNKNOWN:
+		break;
+	}
+	return artwork_pathname("hdd.png");
+}
+
diff --git a/discover/parser.h b/discover/parser.h
new file mode 100644
index 0000000..9c6fb35
--- /dev/null
+++ b/discover/parser.h
@@ -0,0 +1,46 @@
+
+#ifndef _PARSERS_H
+#define _PARSERS_H
+
+#include <stdarg.h>
+#include "message.h"
+
+struct parser {
+	char *name;
+	int priority;
+	int (*parse)(const char *device);
+	struct parser *next;
+};
+
+enum generic_icon_type {
+	ICON_TYPE_DISK,
+	ICON_TYPE_USB,
+	ICON_TYPE_OPTICAL,
+	ICON_TYPE_NETWORK,
+	ICON_TYPE_UNKNOWN
+};
+
+#define streq(a,b) (!strcasecmp((a),(b)))
+
+/* general functions provided by parsers.c */
+void iterate_parsers(const char *devpath, const char *mountpoint);
+
+void free_device(struct device *dev);
+void free_boot_option(struct boot_option *opt);
+
+const char *generic_icon_file(enum generic_icon_type type);
+
+/* functions provided by udev-helper or the test wrapper */
+void pb_log(const char *fmt, ...);
+
+int mount_device(const char *dev_path);
+
+char *resolve_path(const char *path, const char *current_dev);
+const char *mountpoint_for_device(const char *dev_path);
+
+enum generic_icon_type guess_device_type(void);
+
+int add_device(const struct device *dev);
+int add_boot_option(const struct boot_option *opt);
+
+#endif /* _PARSERS_H */
diff --git a/discover/paths.c b/discover/paths.c
new file mode 100644
index 0000000..2373c28
--- /dev/null
+++ b/discover/paths.c
@@ -0,0 +1,141 @@
+#define _GNU_SOURCE
+
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "paths.h"
+
+static char *mount_base;
+
+struct device_map {
+	char *dev, *mnt;
+};
+
+#define DEVICE_MAP_SIZE 32
+static struct device_map device_map[DEVICE_MAP_SIZE];
+
+char *encode_label(const char *label)
+{
+	char *str, *c;
+	int i;
+
+	/* the label can be expanded by up to four times */
+	str = malloc(strlen(label) * 4 + 1);
+	c = str;
+
+	for (i = 0; i < strlen(label); i++) {
+
+		if (label[i] == '/' || label[i] == '\\') {
+			sprintf(c, "\\x%02x", label[i]);
+			c += 4;
+			continue;
+		}
+
+		*(c++) = label[i];
+	}
+
+	*c = '\0';
+
+	return str;
+}
+
+char *parse_device_path(const char *dev_str, const char *cur_dev)
+{
+	char *dev, tmp[256], *enc;
+
+	if (!strncasecmp(dev_str, "uuid=", 5)) {
+		asprintf(&dev, "/dev/disk/by-uuid/%s", dev_str + 5);
+		return dev;
+	}
+
+	if (!strncasecmp(dev_str, "label=", 6)) {
+		enc = encode_label(dev_str + 6);
+		asprintf(&dev, "/dev/disk/by-label/%s", enc);
+		free(enc);
+		return dev;
+	}
+
+	/* normalise '/dev/foo' to 'foo' for easy comparisons, we'll expand
+	 * back before returning.
+	 */
+	if (!strncmp(dev_str, "/dev/", 5))
+		dev_str += 5;
+
+	/* PS3 hack: if we're reading from a ps3dx device, and we refer to
+	 * a sdx device, remap to ps3dx */
+	if (cur_dev && !strncmp(cur_dev, "/dev/ps3d", 9)
+			&& !strncmp(dev_str, "sd", 2)) {
+		snprintf(tmp, 255, "ps3d%s", dev_str + 2);
+		dev_str = tmp;
+	}
+
+	return join_paths("/dev", dev_str);
+}
+
+const char *mountpoint_for_device(const char *dev)
+{
+	int i;
+
+	if (!strncmp(dev, "/dev/", 5))
+		dev += 5;
+
+	/* check existing entries in the map */
+	for (i = 0; (i < DEVICE_MAP_SIZE) && device_map[i].dev; i++)
+		if (!strcmp(device_map[i].dev, dev))
+			return device_map[i].mnt;
+
+	if (i == DEVICE_MAP_SIZE)
+		return NULL;
+
+	device_map[i].dev = strdup(dev);
+	device_map[i].mnt = join_paths(mount_base, dev);
+	return device_map[i].mnt;
+}
+
+char *resolve_path(const char *path, const char *current_dev)
+{
+	char *ret;
+	const char *devpath, *sep;
+
+	sep = strchr(path, ':');
+	if (!sep) {
+		devpath = mountpoint_for_device(current_dev);
+		ret = join_paths(devpath, path);
+	} else {
+		/* parse just the device name into dev */
+		char *tmp, *dev;
+		tmp = strndup(path, sep - path);
+		dev = parse_device_path(tmp, current_dev);
+
+		devpath = mountpoint_for_device(dev);
+		ret = join_paths(devpath, sep + 1);
+
+		free(dev);
+		free(tmp);
+	}
+
+	return ret;
+}
+
+void set_mount_base(const char *path)
+{
+	if (mount_base)
+		free(mount_base);
+	mount_base = strdup(path);
+}
+
+char *join_paths(const char *a, const char *b)
+{
+	char *full_path;
+
+	full_path = malloc(strlen(a) + strlen(b) + 2);
+
+	strcpy(full_path, a);
+	if (b[0] != '/' && a[strlen(a) - 1] != '/')
+		strcat(full_path, "/");
+	strcat(full_path, b);
+
+	return full_path;
+}
+
diff --git a/discover/paths.h b/discover/paths.h
new file mode 100644
index 0000000..26d4ce4
--- /dev/null
+++ b/discover/paths.h
@@ -0,0 +1,53 @@
+#ifndef PATHS_H
+#define PATHS_H
+
+/**
+ * Given a string (eg /dev/sda1, sda1 or UUID=B8E53381CA9EA0E3), parse the
+ * device path (eg /dev/sda1). Any device descriptions read from config files
+ * should be parsed into the path first.
+ *
+ * The cur_dev is provided for some remapping situations. If NULL is provided,
+ * no remapping will be done.
+ *
+ * Returns a newly-allocated string.
+ */
+char *parse_device_path(const char *dev_str, const char *current_device);
+
+/**
+ * Get the mountpoint for a device.
+ */
+const char *mountpoint_for_device(const char *dev);
+
+/**
+ * Resolve a path given in a config file, to a path in the local filesystem.
+ * Paths may be of the form:
+ *  device:path (eg /dev/sda:/boot/vmlinux)
+ *
+ * or just a path:
+ *  /boot/vmlinux
+ * - in this case, the current mountpoint is used.
+ *
+ * Returns a newly-allocated string containing a full path to the file in path
+ */
+char *resolve_path(const char *path, const char *current_device);
+
+
+/**
+ * Set the base directory for newly-created mountpoints
+ */
+void set_mount_base(const char *path);
+
+/**
+ * Utility function for joining two paths. Adds a / between a and b if
+ * required.
+ *
+ * Returns a newly-allocated string.
+ */
+char *join_paths(const char *a, const char *b);
+
+/**
+ * encode a disk label (or uuid) for use in a symlink.
+ */
+char *encode_label(const char *label);
+
+#endif /* PATHS_H */
diff --git a/discover/pb-discover.c b/discover/pb-discover.c
new file mode 100644
index 0000000..45b6ba1
--- /dev/null
+++ b/discover/pb-discover.c
@@ -0,0 +1,34 @@
+
+#include <stdlib.h>
+#include <signal.h>
+
+#include "udev.h"
+#include "discover-server.h"
+#include "waiter.h"
+#include "log.h"
+
+
+int main(void)
+{
+	struct discover_server *server;
+	struct udev *udev;
+
+	/* we look for closed sockets when we write, so ignore SIGPIPE */
+	signal(SIGPIPE, SIG_IGN);
+
+	udev = udev_init();
+	if (!udev)
+		return EXIT_FAILURE;
+
+	server = discover_server_init();
+	if (!server)
+		return EXIT_FAILURE;
+
+	for (;;) {
+		if (waiter_poll())
+			return EXIT_FAILURE;
+	}
+
+
+	return EXIT_SUCCESS;
+}
diff --git a/discover/pb-discover.h b/discover/pb-discover.h
new file mode 100644
index 0000000..a48557c
--- /dev/null
+++ b/discover/pb-discover.h
@@ -0,0 +1,6 @@
+#ifndef _PB_DISCOVER_H
+#define _PB_DISCOVER_H
+
+int register_waiter(int fd, int *callback(void *), void *arg);
+
+#endif /* _PB_DISCOVER_H */
diff --git a/discover/udev.c b/discover/udev.c
new file mode 100644
index 0000000..9c1b399
--- /dev/null
+++ b/discover/udev.c
@@ -0,0 +1,208 @@
+
+#define _GNU_SOURCE
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+#include <talloc/talloc.h>
+
+#include "udev.h"
+#include "log.h"
+#include "waiter.h"
+#include "pb-discover.h"
+
+#define PBOOT_DEVICE_SOCKET "/tmp/petitboot.udev"
+
+#define max(a, b) ((a) > (b) ? (a) : (b))
+
+struct udev {
+	int socket;
+};
+
+static void parse_event_params(struct udev_event *event, char *buf, int len)
+{
+	int param_len, name_len, value_len;
+	struct param *param;
+	char *sep;
+
+	for (; len > 0; len -= param_len + 1, buf += param_len + 1) {
+
+		/* find the length of the whole parameter */
+		param_len = strnlen(buf, len);
+		if (!param_len) {
+			/* multiple NULs? skip over */
+			param_len = 1;
+			continue;
+		}
+
+		/* find the separator */
+		sep = memchr(buf, '=', param_len);
+		if (!sep)
+			continue;
+
+		name_len = sep - buf;
+		value_len = param_len - name_len - 1;
+
+		/* update the params array */
+		event->params = talloc_realloc(event, event->params,
+					struct param, ++event->n_params);
+		param = &event->params[event->n_params - 1];
+
+		param->name = talloc_strndup(event, buf, name_len);
+		param->value = talloc_strndup(event, sep + 1, value_len);
+	}
+}
+
+static const char *event_param(struct udev_event *event, const char *name)
+{
+	int i;
+
+	for (i = 0; i < event->n_params; i++)
+		if (!strcasecmp(event->params[i].name, name))
+			return event->params[i].value;
+
+	return NULL;
+}
+
+static void print_event(struct udev_event *event)
+{
+	const char *action, *params[] = {
+		"DEVNAME", "ID_TYPE", "ID_BUS", "ID_FS_UUID", "ID_FS_LABEL",
+		NULL,
+	};
+	int i;
+
+	action = event->action == UDEV_ACTION_ADD ? "add" : "remove";
+
+	pb_log("udev %s event:\n", action);
+	printf("\tdevice: %s\n", event->device);
+
+	for (i = 0; params[i]; i++)
+		printf("\t%-12s => %s\n",
+				params[i], event_param(event, params[i]));
+
+}
+
+static void handle_udev_message(struct udev *udev, char *buf, int len)
+{
+	char *sep, *device;
+	enum udev_action action;
+	struct udev_event *event;
+	int device_len;
+
+	/* we should see an <action>@<device>\0 at the head of the buffer */
+	sep = strchr(buf, '@');
+	if (!sep)
+		return;
+
+	/* terminate the action string */
+	*sep = '\0';
+	len -= sep - buf + 1;
+
+	if (!strcmp(buf, "add")) {
+		action = UDEV_ACTION_ADD;
+
+	} else if (!strcmp(buf, "remove")) {
+		action = UDEV_ACTION_REMOVE;
+
+	} else {
+		return;
+	}
+
+	/* initialise the device string */
+	device = sep + 1;
+	device_len = strnlen(device, len);
+	if (!device_len)
+		return;
+
+	/* now we have an action and a device, we can construct an event */
+	event = talloc(udev, struct udev_event);
+	event->action = action;
+	event->device = talloc_strndup(event, device, device_len);
+	event->n_params = 0;
+	event->params = NULL;
+
+	len -= device_len + 1;
+	parse_event_params(event, device + device_len + 1, len);
+
+	print_event(event);
+
+	talloc_free(event);
+
+	return;
+}
+
+static int udev_process(void *arg)
+{
+	struct udev *udev = arg;
+	char buf[4096];
+	int len;
+
+	len = recvfrom(udev->socket, buf, sizeof(buf), 0, NULL, NULL);
+
+	if (len < 0) {
+		pb_log("udev socket read failed: %s", strerror(errno));
+		return -1;
+	}
+
+	if (len == 0)
+		return 0;
+
+	handle_udev_message(udev, buf, len);
+
+	return 0;
+}
+
+static int udev_destructor(void *p)
+{
+	struct udev *udev = p;
+
+	if (udev->socket >= 0)
+		close(udev->socket);
+
+	return 0;
+}
+
+struct udev *udev_init(void)
+{
+	struct sockaddr_un addr;
+	struct udev *udev;
+
+	unlink(PBOOT_DEVICE_SOCKET);
+
+	udev = talloc(NULL, struct udev);
+
+	udev->socket = socket(PF_UNIX, SOCK_DGRAM, 0);
+	if (udev->socket < 0) {
+		pb_log("Error creating udev socket: %s\n", strerror(errno));
+		goto out_err;
+	}
+
+	talloc_set_destructor(udev, udev_destructor);
+
+	addr.sun_family = AF_UNIX;
+	strcpy(addr.sun_path, PBOOT_DEVICE_SOCKET);
+
+	if (bind(udev->socket, (struct sockaddr *)&addr, sizeof(addr))) {
+		pb_log("Error binding udev socket: %s\n", strerror(errno));
+		goto out_err;
+	}
+
+	waiter_register(udev->socket, WAIT_IN, udev_process, udev);
+
+	return udev;
+
+out_err:
+	talloc_free(udev);
+	return NULL;
+}
+
+void udev_destroy(struct udev *udev)
+{
+	talloc_free(udev);
+}
diff --git a/discover/udev.h b/discover/udev.h
new file mode 100644
index 0000000..c30adc9
--- /dev/null
+++ b/discover/udev.h
@@ -0,0 +1,26 @@
+#ifndef _UDEV_H
+#define _UDEV_H
+
+enum udev_action {
+	UDEV_ACTION_ADD,
+	UDEV_ACTION_REMOVE,
+};
+
+struct udev_event {
+	enum udev_action action;
+	char *device;
+
+	struct param {
+		char *name;
+		char *value;
+	} *params;
+	int n_params;
+};
+
+struct udev;
+
+struct udev *udev_init(void);
+
+void udev_destroy(struct udev *udev);
+
+#endif /* _UDEV_H */
diff --git a/discover/waiter.c b/discover/waiter.c
new file mode 100644
index 0000000..21dd4a5
--- /dev/null
+++ b/discover/waiter.c
@@ -0,0 +1,83 @@
+
+#include <poll.h>
+#include <string.h>
+#include <assert.h>
+
+#include <talloc/talloc.h>
+
+#include "waiter.h"
+
+struct waiter {
+	int		fd;
+	int		events;
+	waiter_cb	callback;
+	void		*arg;
+};
+
+static struct waiter *waiters;
+static int n_waiters;
+
+struct waiter *waiter_register(int fd, int events,
+		waiter_cb callback, void *arg)
+{
+	struct waiter *waiter;
+
+	n_waiters++;
+
+	waiters = talloc_realloc(NULL, waiters, struct waiter, n_waiters);
+	waiter = &waiters[n_waiters - 1];
+
+	waiter->fd = fd;
+	waiter->events = events;
+	waiter->callback = callback;
+	waiter->arg = arg;
+
+	return 0;
+}
+
+void waiter_remove(struct waiter *waiter)
+{
+	int i;
+
+	i = waiter - waiters;
+	assert(i >= 0 && i < n_waiters);
+
+	n_waiters--;
+	memmove(&waiters[i], &waiters[i+1], n_waiters - i);
+
+	waiters = talloc_realloc(NULL, waiters, struct waiter, n_waiters);
+}
+
+int waiter_poll(void)
+{
+	static struct pollfd *pollfds;
+	static int n_pollfds;
+	int i, rc;
+
+	if (n_waiters > n_pollfds) {
+		pollfds = talloc_realloc(NULL, pollfds,
+				struct pollfd, n_waiters);
+	}
+
+	for (i = 0; i < n_waiters; i++) {
+		pollfds[i].fd = waiters[i].fd;
+		pollfds[i].events = waiters[i].events;
+		pollfds[i].revents = 0;
+	}
+
+	rc = poll(pollfds, n_waiters, -1);
+
+	if (rc <= 0)
+		return rc;
+
+	for (i = 0; i < n_waiters; i++) {
+		if (pollfds[i].revents) {
+			rc = waiters[i].callback(waiters[i].arg);
+
+			if (rc)
+				waiter_remove(&waiters[i]);
+		}
+	}
+
+	return 0;
+}
diff --git a/discover/waiter.h b/discover/waiter.h
new file mode 100644
index 0000000..ff8a5ff
--- /dev/null
+++ b/discover/waiter.h
@@ -0,0 +1,23 @@
+#ifndef _WAITER_H
+#define _WAITER_H
+
+#include <poll.h>
+
+struct waiter;
+
+enum events {
+	WAIT_IN  = POLLIN,
+	WAIT_OUT = POLLOUT,
+};
+
+typedef int (*waiter_cb)(void *);
+
+struct waiter *waiter_register(int fd, int events,
+		waiter_cb callback, void *arg);
+
+void waiter_remove(struct waiter *waiter);
+
+int waiter_poll(void);
+#endif /* _WAITER_H */
+
+
diff --git a/discover/yaboot-cfg.c b/discover/yaboot-cfg.c
new file mode 100644
index 0000000..6b007e4
--- /dev/null
+++ b/discover/yaboot-cfg.c
@@ -0,0 +1,491 @@
+/*
+ *  cfg.c - Handling and parsing of yaboot.conf
+ *
+ *  Copyright (C) 1995 Werner Almesberger
+ *                1996 Jakub Jelinek
+ *
+ *  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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#include <setjmp.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#define prom_printf printf
+#define prom_putchar putchar
+#define prom_vprintf vprintf
+
+/* Imported functions */
+extern int strcasecmp(const char *s1, const char *s2);
+
+typedef enum {
+     cft_strg, cft_flag, cft_end
+} CONFIG_TYPE;
+
+typedef struct {
+     CONFIG_TYPE type;
+     char *name;
+     void *data;
+} CONFIG;
+
+#define MAX_TOKEN 200
+#define MAX_VAR_NAME MAX_TOKEN
+char *cfg_get_default (void);
+
+CONFIG cf_options[] =
+{
+     {cft_strg, "device", NULL},
+     {cft_strg, "partition", NULL},
+     {cft_strg, "default", NULL},
+     {cft_strg, "timeout", NULL},
+     {cft_strg, "password", NULL},
+     {cft_flag, "restricted", NULL},
+     {cft_strg, "message", NULL},
+     {cft_strg, "root", NULL},
+     {cft_strg, "ramdisk", NULL},
+     {cft_flag, "read-only", NULL},
+     {cft_flag, "read-write", NULL},
+     {cft_strg, "append", NULL},
+     {cft_strg, "initrd", NULL},
+     {cft_flag, "initrd-prompt", NULL},
+     {cft_strg, "initrd-size", NULL},
+     {cft_flag, "pause-after", NULL},
+     {cft_strg, "pause-message", NULL},
+     {cft_strg, "init-code", NULL},
+     {cft_strg, "init-message", NULL},
+     {cft_strg, "fgcolor", NULL},
+     {cft_strg, "bgcolor", NULL},
+     {cft_strg, "ptypewarning", NULL},
+     {cft_end, NULL, NULL}};
+
+CONFIG cf_image[] =
+{
+     {cft_strg, "image", NULL},
+     {cft_strg, "label", NULL},
+     {cft_strg, "alias", NULL},
+     {cft_flag, "single-key", NULL},
+     {cft_flag, "restricted", NULL},
+     {cft_strg, "device", NULL},
+     {cft_strg, "partition", NULL},
+     {cft_strg, "root", NULL},
+     {cft_strg, "ramdisk", NULL},
+     {cft_flag, "read-only", NULL},
+     {cft_flag, "read-write", NULL},
+     {cft_strg, "append", NULL},
+     {cft_strg, "literal", NULL},
+     {cft_strg, "initrd", NULL},
+     {cft_flag, "initrd-prompt", NULL},
+     {cft_strg, "initrd-size", NULL},
+     {cft_flag, "pause-after", NULL},
+     {cft_strg, "pause-message", NULL},
+     {cft_flag, "novideo", NULL},
+     {cft_strg, "sysmap", NULL},
+     {cft_end, NULL, NULL}};
+
+static char flag_set;
+static char *last_token = NULL, *last_item = NULL, *last_value = NULL;
+static int line_num;
+static int back = 0;		/* can go back by one char */
+static char *currp = NULL;
+static char *endp = NULL;
+static char *file_name = NULL;
+static CONFIG *curr_table = cf_options;
+static jmp_buf env;
+
+static struct IMAGES {
+     CONFIG table[sizeof (cf_image) / sizeof (cf_image[0])];
+     struct IMAGES *next;
+} *images = NULL;
+
+void cfg_error (char *msg,...)
+{
+     va_list ap;
+
+     va_start (ap, msg);
+     prom_printf ("Config file error: ");
+     prom_vprintf (msg, ap);
+     va_end (ap);
+     prom_printf (" near line %d in file %s\n", line_num, file_name);
+     longjmp (env, 1);
+}
+
+void cfg_warn (char *msg,...)
+{
+     va_list ap;
+
+     va_start (ap, msg);
+     prom_printf ("Config file warning: ");
+     prom_vprintf (msg, ap);
+     va_end (ap);
+     prom_printf (" near line %d in file %s\n", line_num, file_name);
+}
+
+int cfg_getc ()
+{
+     if (currp == endp)
+	  return EOF;
+     return *currp++;
+}
+
+#define next_raw next
+static int next (void)
+{
+     int ch;
+
+     if (!back)
+	  return cfg_getc ();
+     ch = back;
+     back = 0;
+     return ch;
+}
+
+static void again (int ch)
+{
+     back = ch;
+}
+
+static char *cfg_get_token (void)
+{
+     char buf[MAX_TOKEN + 1];
+     char *here;
+     int ch, escaped;
+
+     if (last_token) {
+	  here = last_token;
+	  last_token = NULL;
+	  return here;
+     }
+     while (1) {
+	  while (ch = next (), ch == ' ' || ch == '\t' || ch == '\n' || ch == '\r')
+	       if (ch == '\n' || ch == '\r')
+		    line_num++;
+	  if (ch == EOF || ch == (int)NULL)
+	       return NULL;
+	  if (ch != '#')
+	       break;
+	  while (ch = next_raw (), (ch != '\n' && ch != '\r'))
+	       if (ch == EOF)
+		    return NULL;
+	  line_num++;
+     }
+     if (ch == '=')
+	  return strdup ("=");
+     if (ch == '"') {
+	  here = buf;
+	  while (here - buf < MAX_TOKEN) {
+	       if ((ch = next ()) == EOF)
+		    cfg_error ("EOF in quoted string");
+	       if (ch == '"') {
+		    *here = 0;
+		    return strdup (buf);
+	       }
+	       if (ch == '\\') {
+		    ch = next ();
+		    switch (ch) {
+		    case '"':
+		    case '\\':
+			 break;
+		    case '\n':
+		    case '\r':
+			 while ((ch = next ()), ch == ' ' || ch == '\t');
+			 if (!ch)
+			      continue;
+			 again (ch);
+			 ch = ' ';
+			 break;
+		    case 'n':
+			 ch = '\n';
+			 break;
+		    default:
+			 cfg_error ("Bad use of \\ in quoted string");
+		    }
+	       } else if ((ch == '\n') || (ch == '\r'))
+		    cfg_error ("newline is not allowed in quoted strings");
+	       *here++ = ch;
+	  }
+	  cfg_error ("Quoted string is too long");
+	  return 0;		/* not reached */
+     }
+     here = buf;
+     escaped = 0;
+     while (here - buf < MAX_TOKEN) {
+	  if (escaped) {
+	       if (ch == EOF)
+		    cfg_error ("\\ precedes EOF");
+	       if (ch == '\n')
+		    line_num++;
+	       else
+		    *here++ = ch == '\t' ? ' ' : ch;
+	       escaped = 0;
+	  } else {
+	       if (ch == ' ' || ch == '\t' || ch == '\n' || ch == '\r' || ch == '#' ||
+		   ch == '=' || ch == EOF) {
+		    again (ch);
+		    *here = 0;
+		    return strdup (buf);
+	       }
+	       if (!(escaped = (ch == '\\')))
+		    *here++ = ch;
+	  }
+	  ch = next ();
+     }
+     cfg_error ("Token is too long");
+     return 0;			/* not reached */
+}
+
+static void cfg_return_token (char *token)
+{
+     last_token = token;
+}
+
+static int cfg_next (char **item, char **value)
+{
+     char *this;
+
+     if (last_item) {
+	  *item = last_item;
+	  *value = last_value;
+	  last_item = NULL;
+	  return 1;
+     }
+     *value = NULL;
+     if (!(*item = cfg_get_token ()))
+	  return 0;
+     if (!strcmp (*item, "="))
+	  cfg_error ("Syntax error");
+     if (!(this = cfg_get_token ()))
+	  return 1;
+     if (strcmp (this, "=")) {
+	  cfg_return_token (this);
+	  return 1;
+     }
+     if (!(*value = cfg_get_token ()))
+	  cfg_error ("Value expected at EOF");
+     if (!strcmp (*value, "="))
+	  cfg_error ("Syntax error after %s", *item);
+     return 1;
+}
+
+#if 0
+// The one and only call to this procedure is commented out
+// below, so we don't need this unless we decide to use it again.
+static void cfg_return (char *item, char *value)
+{
+     last_item = item;
+     last_value = value;
+}
+#endif
+
+static int cfg_set (char *item, char *value)
+{
+     CONFIG *walk;
+
+     if (!strcasecmp (item, "image")) {
+	  struct IMAGES **p = &images;
+
+	  while (*p)
+	       p = &((*p)->next);
+	  *p = (struct IMAGES *)malloc (sizeof (struct IMAGES));
+	  if (*p == NULL) {
+	       prom_printf("malloc error in cfg_set\n");
+	       return -1;
+	  }
+	  (*p)->next = 0;
+	  curr_table = ((*p)->table);
+	  memcpy (curr_table, cf_image, sizeof (cf_image));
+     }
+     for (walk = curr_table; walk->type != cft_end; walk++) {
+	  if (walk->name && !strcasecmp (walk->name, item)) {
+	       if (value && walk->type != cft_strg)
+		    cfg_warn ("'%s' doesn't have a value", walk->name);
+	       else if (!value && walk->type == cft_strg)
+		    cfg_warn ("Value expected for '%s'", walk->name);
+	       else {
+		    if (walk->data)
+			 cfg_warn ("Duplicate entry '%s'", walk->name);
+		    if (walk->type == cft_flag)
+			 walk->data = &flag_set;
+		    else if (walk->type == cft_strg)
+			 walk->data = value;
+	       }
+	       break;
+	  }
+     }
+     if (walk->type != cft_end)
+	  return 1;
+//    cfg_return (item, value);
+     return 0;
+}
+
+int cfg_parse (char *cfg_file, char *buff, int len)
+{
+     char *item, *value;
+
+     file_name = cfg_file;
+     currp = buff;
+     endp = currp + len;
+
+     if (setjmp (env))
+	  return -1;
+     while (1) {
+	  if (!cfg_next (&item, &value))
+	       return 0;
+	  if (!cfg_set (item, value)) {
+#if DEBUG
+	       prom_printf("Can't set item %s to value %s\n", item, value);
+#endif	    
+	  }
+	  free (item);
+     }
+}
+
+static char *cfg_get_strg_i (CONFIG * table, char *item)
+{
+     CONFIG *walk;
+
+     for (walk = table; walk->type != cft_end; walk++)
+	  if (walk->name && !strcasecmp (walk->name, item))
+	       return walk->data;
+     return 0;
+}
+
+char *cfg_get_strg (char *image, char *item)
+{
+     struct IMAGES *p;
+     char *label, *alias;
+     char *ret;
+
+     if (!image)
+	  return cfg_get_strg_i (cf_options, item);
+     for (p = images; p; p = p->next) {
+	  label = cfg_get_strg_i (p->table, "label");
+	  if (!label) {
+	       label = cfg_get_strg_i (p->table, "image");
+	       alias = strrchr (label, '/');
+	       if (alias)
+		    label = alias + 1;
+	  }
+	  alias = cfg_get_strg_i (p->table, "alias");
+	  if (!strcmp (label, image) || (alias && !strcmp (alias, image))) {
+	       ret = cfg_get_strg_i (p->table, item);
+	       if (!ret)
+		    ret = cfg_get_strg_i (cf_options, item);
+	       return ret;
+	  }
+     }
+     return 0;
+}
+
+int cfg_get_flag (char *image, char *item)
+{
+     return !!cfg_get_strg (image, item);
+}
+
+static int printl_count = 0;
+static void printlabel (char *label, int defflag)
+{
+     int len = strlen (label);
+
+     if (!printl_count)
+	  prom_printf ("\n");
+     prom_printf ("%s %s",defflag?"*":" ", label);
+     while (len++ < 25)
+	  prom_putchar (' ');
+     printl_count++;
+     if (printl_count == 3)
+	  printl_count = 0;
+}
+
+void cfg_print_images (void)
+{
+     struct IMAGES *p;
+     char *label, *alias;
+
+     char *ret = cfg_get_default();//strg_i (cf_options, "default");
+     int defflag=0;
+
+     printl_count = 0;
+     for (p = images; p; p = p->next) {
+	  label = cfg_get_strg_i (p->table, "label");
+	  if (!label) {
+	       label = cfg_get_strg_i (p->table, "image");
+	       alias = strrchr (label, '/');
+	       if (alias)
+		    label = alias + 1;
+	  }
+	  if(!strcmp(ret,label))
+	       defflag=1;
+	  else
+	       defflag=0;
+	  alias = cfg_get_strg_i (p->table, "alias");
+	  printlabel (label, defflag);
+	  if (alias)
+	       printlabel (alias, 0);
+     }
+     prom_printf("\n");
+}
+
+char *cfg_get_default (void)
+{
+     char *label;
+     char *ret = cfg_get_strg_i (cf_options, "default");
+
+     if (ret)
+	  return ret;
+     if (!images)
+	  return 0;
+     ret = cfg_get_strg_i (images->table, "label");
+     if (!ret) {
+	  ret = cfg_get_strg_i (images->table, "image");
+	  label = strrchr (ret, '/');
+	  if (label)
+	       ret = label + 1;
+     }
+     return ret;
+}
+
+char *cfg_next_image(char *prev)
+{
+     struct IMAGES *p;
+     char *label, *alias;
+     int wantnext = 0;
+
+     if (!prev)
+	  wantnext = 1;
+
+     for (p = images; p; p = p->next) {
+	  label = cfg_get_strg_i (p->table, "label");
+	  if (!label) {
+	       label = cfg_get_strg_i (p->table, "image");
+	       alias = strrchr (label, '/');
+	       if (alias)
+		    label = alias + 1;
+	  }
+	  if (wantnext)
+	       return label;
+	  if (!strcmp(prev, label))
+	       wantnext = 1;
+     }
+     return NULL;
+}
+/* 
+ * Local variables:
+ * c-file-style: "k&r"
+ * c-basic-offset: 5
+ * End:
+ */
diff --git a/discover/yaboot-cfg.h b/discover/yaboot-cfg.h
new file mode 100644
index 0000000..2ab4fec
--- /dev/null
+++ b/discover/yaboot-cfg.h
@@ -0,0 +1,30 @@
+/*
+ *  cfg.h - config file parsing definitions
+ *
+ *  Copyright (C) 1999 Benjamin Herrenschmidt
+ *
+ *  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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#ifndef CFG_H
+#define CFG_H
+
+extern int	cfg_parse(char *cfg_file, char *buff, int len);
+extern char*	cfg_get_strg(char *image, char *item);
+extern int	cfg_get_flag(char *image, char *item);
+extern void	cfg_print_images(void);
+extern char*	cfg_get_default(void);
+extern char*	cfg_next_image(char *);
+#endif
diff --git a/discover/yaboot-parser.c b/discover/yaboot-parser.c
new file mode 100644
index 0000000..27b4b78
--- /dev/null
+++ b/discover/yaboot-parser.c
@@ -0,0 +1,235 @@
+
+#include "parser.h"
+#include "params.h"
+#include "paths.h"
+#include "yaboot-cfg.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include <sys/param.h>
+
+static struct device *dev;
+static char *devpath;
+static char *defimage;
+
+char *
+make_params(char *label, char *params)
+{
+     char *p, *q;
+     static char buffer[2048];
+
+     q = buffer;
+     *q = 0;
+
+     p = cfg_get_strg(label, "literal");
+     if (p) {
+          strcpy(q, p);
+          q = strchr(q, 0);
+          if (params) {
+               if (*p)
+                    *q++ = ' ';
+               strcpy(q, params);
+          }
+          return buffer;
+     }
+
+     p = cfg_get_strg(label, "root");
+     if (p) {
+          strcpy (q, "root=");
+          strcpy (q + 5, p);
+          q = strchr (q, 0);
+          *q++ = ' ';
+     }
+     if (cfg_get_flag(label, "read-only")) {
+          strcpy (q, "ro ");
+          q += 3;
+     }
+     if (cfg_get_flag(label, "read-write")) {
+          strcpy (q, "rw ");
+          q += 3;
+     }
+     p = cfg_get_strg(label, "ramdisk");
+     if (p) {
+          strcpy (q, "ramdisk=");
+          strcpy (q + 8, p);
+          q = strchr (q, 0);
+          *q++ = ' ';
+     }
+     p = cfg_get_strg(label, "initrd-size");
+     if (p) {
+          strcpy (q, "ramdisk_size=");
+          strcpy (q + 13, p);
+          q = strchr (q, 0);
+          *q++ = ' ';
+     }
+     if (cfg_get_flag(label, "novideo")) {
+          strcpy (q, "video=ofonly");
+          q = strchr (q, 0);
+          *q++ = ' ';
+     }
+     p = cfg_get_strg (label, "append");
+     if (p) {
+          strcpy (q, p);
+          q = strchr (q, 0);
+          *q++ = ' ';
+     }
+     *q = 0;
+     if (params)
+          strcpy(q, params);
+
+     return buffer;
+}
+
+static int check_and_add_device(struct device *dev)
+{
+	if (!dev->icon_file)
+		dev->icon_file = strdup(generic_icon_file(guess_device_type()));
+
+	return !add_device(dev);
+}
+
+void process_image(char *label)
+{
+	struct boot_option opt;
+	char *cfgopt;
+
+	memset(&opt, 0, sizeof(opt));
+
+	opt.name = label;
+	cfgopt = cfg_get_strg(label, "image");
+	opt.boot_image_file = resolve_path(cfgopt, devpath);
+	if (cfgopt == defimage)
+		pb_log("This one is default. What do we do about it?\n");
+
+	cfgopt = cfg_get_strg(label, "initrd");
+	if (cfgopt)
+		opt.initrd_file = resolve_path(cfgopt, devpath);
+
+	opt.boot_args = make_params(label, NULL);
+
+	add_boot_option(&opt);
+
+	if (opt.initrd_file)
+		free(opt.initrd_file);
+}
+
+static int yaboot_parse(const char *device)
+{
+	char *filepath;
+	char *conf_file;
+	char *tmpstr;
+	ssize_t conf_len;
+	int fd;
+	struct stat st;
+	char *label;
+
+	devpath = strdup(device);
+
+	filepath = resolve_path("/etc/yaboot.conf", devpath);
+
+	fd = open(filepath, O_RDONLY);
+	if (fd < 0) {
+		free(filepath);
+		filepath = resolve_path("/yaboot.conf", devpath);
+		fd = open(filepath, O_RDONLY);
+		
+		if (fd < 0)
+			return 0;
+	}
+
+	if (fstat(fd, &st)) {
+		close(fd);
+		return 0;
+	}
+
+	conf_file = malloc(st.st_size+1);
+	if (!conf_file) {
+		close(fd);
+		return 0;
+	}
+	
+	conf_len = read(fd, conf_file, st.st_size);
+	if (conf_len < 0) {
+		close(fd);
+		return 0;
+	}
+	conf_file[conf_len] = 0;
+
+	close(fd);
+	
+	if (cfg_parse(filepath, conf_file, conf_len)) {
+		pb_log("Error parsing yaboot.conf\n");
+		return 0;
+	}
+
+	free(filepath);
+
+	dev = malloc(sizeof(*dev));
+	memset(dev, 0, sizeof(*dev));
+	dev->id = strdup(devpath);
+	if (cfg_get_strg(0, "init-message")) {
+		char *newline;
+		dev->description = strdup(cfg_get_strg(0, "init-message"));
+		newline = strchr(dev->description, '\n');
+		if (newline)
+			*newline = 0;
+	}
+	dev->icon_file = strdup(generic_icon_file(guess_device_type()));
+
+	/* If we have a 'partiton=' directive, update the default devpath
+	 * to use that instead of the current device */
+	tmpstr = cfg_get_strg(0, "partition");
+	if (tmpstr) {
+		char *endp;
+		int partnr = strtol(tmpstr, &endp, 10);
+		if (endp != tmpstr && !*endp) {
+			char *new_dev, *tmp;
+
+			new_dev = malloc(strlen(devpath) + strlen(tmpstr) + 1);
+			if (!new_dev)
+				return 0;
+
+			strcpy(new_dev, devpath);
+
+			/* Strip digits (partition number) from string */
+			endp = new_dev + strlen(devpath) - 1;
+			while (isdigit(*endp))
+				*(endp--) = 0;
+
+			/* and add our own... */
+			sprintf(endp + 1, "%d", partnr);
+
+			tmp = devpath;
+			devpath = parse_device_path(new_dev, devpath);
+			free(tmp);
+			free(new_dev);
+		}
+	}
+
+	defimage = cfg_get_default();
+	if (!defimage)
+		return 0;
+	defimage = cfg_get_strg(defimage, "image");
+
+	label = cfg_next_image(NULL);
+	if (!label || !check_and_add_device(dev))
+		return 0;
+
+	do {
+		process_image(label);
+	} while ((label = cfg_next_image(label)));
+
+	return 1;
+}
+
+struct parser yaboot_parser = {
+	.name = "yaboot.conf parser",
+	.priority = 99,
+	.parse	  = yaboot_parse
+};