[PATCH] discover: Let 'boot' user-event boot by name

[Samuel Mendoza-Jonas]

If a 'name' parameter is used for a boot user event, search existing
boot options for one that matches that name on the given device.
This allows a pb-event user to boot based on name rather than having to
specify the exact boot arguments.

Signed-off-by: Samuel Mendoza-Jonas <sam at mendozajonas.com>
---
 discover/device-handler.c | 22 ++++++++++++++++++++++
 discover/device-handler.h |  3 +++
 discover/user-event.c     | 29 +++++++++++++++++++++++------
 3 files changed, 48 insertions(+), 6 deletions(-)

diff --git a/discover/device-handler.c b/discover/device-handler.c
index 9c050293..cf379e78 100644
--- a/discover/device-handler.c
+++ b/discover/device-handler.c
@@ -1404,6 +1404,28 @@ int device_handler_dhcp(struct device_handler *handler,
 	return 0;
 }
 
+struct discover_boot_option *device_handler_find_option_by_name(
+		struct device_handler *handler, const char *device,
+		const char *name)
+{
+	size_t len = strlen(name);
+	unsigned int i;
+
+	for (i = 0; i < handler->n_devices; i++) {
+		struct discover_device *dev = handler->devices[i];
+		struct discover_boot_option *opt;
+
+		list_for_each_entry(&dev->boot_options, opt, list)
+			/* Match exactly, partial matches can be quite common */
+			if (strlen(opt->option->name) == len &&
+					!strcmp(opt->option->name, name))
+				if (!dev || !strcmp(opt->option->device_id, device))
+					return opt;
+	}
+
+	return NULL;
+}
+
 static struct discover_boot_option *find_boot_option_by_id(
 		struct device_handler *handler, const char *id)
 {
diff --git a/discover/device-handler.h b/discover/device-handler.h
index 3ca88e4e..9696ec06 100644
--- a/discover/device-handler.h
+++ b/discover/device-handler.h
@@ -157,6 +157,9 @@ void discover_device_set_param(struct discover_device *device,
 const char *discover_device_get_param(struct discover_device *device,
 		const char *name);
 
+struct discover_boot_option *device_handler_find_option_by_name(
+		struct device_handler *handler, const char *device,
+		const char *name);
 void device_handler_boot(struct device_handler *handler,
 		struct boot_command *cmd);
 void device_handler_cancel_default(struct device_handler *handler);
diff --git a/discover/user-event.c b/discover/user-event.c
index 12577964..734f77b3 100644
--- a/discover/user-event.c
+++ b/discover/user-event.c
@@ -482,13 +482,30 @@ static int user_event_url(struct user_event *uev, struct event *event)
 static int user_event_boot(struct user_event *uev, struct event *event)
 {
 	struct device_handler *handler = uev->handler;
-	struct boot_command *cmd = talloc(handler, struct boot_command);
+	struct boot_command *cmd = talloc_zero(handler, struct boot_command);
+	struct discover_boot_option *opt;
+	const char *name;
+
+	name = event_get_param(event, "name");
+	if (name) {
+		pb_log("Finding boot option %s @ %s\n", name, event->device);
+		opt = device_handler_find_option_by_name(handler,
+				event->device, name);
+		if (!opt) {
+			pb_log("No option with name %s\n", name);
+			return -1;
+		}
 
-	cmd->option_id = talloc_strdup(cmd, event_get_param(event, "id"));
-	cmd->boot_image_file = talloc_strdup(cmd, event_get_param(event, "image"));
-	cmd->initrd_file = talloc_strdup(cmd, event_get_param(event, "initrd"));
-	cmd->dtb_file = talloc_strdup(cmd, event_get_param(event, "dtb"));
-	cmd->boot_args = talloc_strdup(cmd, event_get_param(event, "args"));
+		pb_log("Found option with id %s!\n", opt->option->id);
+		cmd->option_id = talloc_strdup(cmd, opt->option->id);
+	} else {
+		pb_log("Booting based on full boot command\n");
+		cmd->option_id = talloc_strdup(cmd, event_get_param(event, "id"));
+		cmd->boot_image_file = talloc_strdup(cmd, event_get_param(event, "image"));
+		cmd->initrd_file = talloc_strdup(cmd, event_get_param(event, "initrd"));
+		cmd->dtb_file = talloc_strdup(cmd, event_get_param(event, "dtb"));
+		cmd->boot_args = talloc_strdup(cmd, event_get_param(event, "args"));
+	}
 
 	device_handler_boot(handler, cmd);
 
-- 
2.18.0