discover: Change parsers to emit resources rather than filenames
[petitboot] / discover / device-handler.c
index 0e902df6b86ed4c1805868617cf7db85abb08bf7..950e730b995b89af52073b0ba8eaf0906d4147a9 100644 (file)
 
+#include <assert.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+
 #include <talloc/talloc.h>
-#include <pb-protocol/pb-protocol.h>
+#include <list/list.h>
+#include <log/log.h>
+#include <types/types.h>
+#include <system/system.h>
 
 #include "device-handler.h"
+#include "discover-server.h"
+#include "event.h"
+#include "parser.h"
+#include "udev.h"
+#include "paths.h"
+#include "boot.h"
 
 struct device_handler {
-       struct discover_server *server;
+       struct discover_server  *server;
+       int                     dry_run;
+
+       struct discover_device  **devices;
+       unsigned int            n_devices;
+};
+
+/**
+ * context_commit - Commit a temporary discovery context to the handler,
+ * and notify the clients about any new options / devices
+ */
+static void context_commit(struct device_handler *handler,
+               struct discover_context *ctx)
+{
+       struct discover_device *dev = ctx->device;
+       struct discover_boot_option *opt, *tmp;
+       unsigned int i, existing_device;
+
+       /* do we already have this device? */
+       for (i = 0; i < handler->n_devices; i++) {
+               if (ctx->device == handler->devices[i]) {
+                       existing_device = 1;
+                       break;
+               }
+       }
+
+       /* if not already present, add the device to the handler's array */
+       if (!existing_device) {
+               handler->n_devices++;
+               handler->devices = talloc_realloc(handler, handler->devices,
+                       struct discover_device *, handler->n_devices);
+               handler->devices[handler->n_devices - 1] = dev;
+               talloc_steal(handler, dev);
+
+               discover_server_notify_device_add(handler->server, dev->device);
+       }
+
+
+       /* move boot options from the context to the device */
+       list_for_each_entry_safe(&ctx->boot_options, opt, tmp, list) {
+               list_remove(&opt->list);
+               list_add(&dev->boot_options, &opt->list);
+               talloc_steal(dev, opt);
+               discover_server_notify_boot_option_add(handler->server,
+                                                       opt->option);
+       }
+}
+
+void discover_context_add_boot_option(struct discover_context *ctx,
+               struct discover_boot_option *boot_option)
+{
+       list_add(&ctx->boot_options, &boot_option->list);
+       talloc_steal(ctx, boot_option);
+}
+
+/**
+ * device_handler_remove - Remove a device from the handler device array.
+ */
+
+static void device_handler_remove(struct device_handler *handler,
+       struct discover_device *device)
+{
+       unsigned int i;
+
+       for (i = 0; i < handler->n_devices; i++)
+               if (handler->devices[i] == device)
+                       break;
+
+       if (i == handler->n_devices) {
+               assert(0 && "unknown device");
+               return;
+       }
+
+       handler->n_devices--;
+       memmove(&handler->devices[i], &handler->devices[i + 1],
+               (handler->n_devices - i) * sizeof(handler->devices[0]));
+       handler->devices = talloc_realloc(handler, handler->devices,
+               struct discover_device *, handler->n_devices);
+
+       discover_server_notify_device_remove(handler->server, device->device);
+
+       talloc_free(device);
+}
+
+/**
+ * device_handler_get_device_count - Get the count of current handler devices.
+ */
+
+int device_handler_get_device_count(const struct device_handler *handler)
+{
+       return handler->n_devices;
+}
+
+/**
+ * device_handler_get_device - Get a handler device by index.
+ */
+
+const struct discover_device *device_handler_get_device(
+       const struct device_handler *handler, unsigned int index)
+{
+       if (index >= handler->n_devices) {
+               assert(0 && "bad index");
+               return NULL;
+       }
+
+       return handler->devices[index];
+}
+
+static int mount_device(struct discover_device *dev)
+{
+       const char *argv[6];
+
+       if (!dev->mount_path)
+               dev->mount_path = join_paths(dev, mount_base(),
+                                               dev->device_path);
+
+       if (pb_mkdir_recursive(dev->mount_path))
+               pb_log("couldn't create mount directory %s: %s\n",
+                               dev->mount_path, strerror(errno));
+
+       argv[0] = pb_system_apps.mount;
+       argv[1] = dev->device_path;
+       argv[2] = dev->mount_path;
+       argv[3] = "-o";
+       argv[4] = "ro";
+       argv[5] = NULL;
+
+       if (pb_run_cmd(argv, 1, 0)) {
+
+               /* Retry mount without ro option. */
+
+               argv[0] = pb_system_apps.mount;
+               argv[1] = dev->device_path;
+               argv[2] = dev->mount_path;
+               argv[3] = NULL;
+
+               if (pb_run_cmd(argv, 1, 0))
+                       goto out_rmdir;
+       }
+
+       return 0;
+
+out_rmdir:
+       pb_rmdir_recursive(mount_base(), dev->mount_path);
+       return -1;
+}
+
+static int umount_device(struct discover_device *dev)
+{
+       int status;
+       pid_t pid;
+
+       if (!dev->mount_path)
+               return 0;
+
+       pid = fork();
+       if (pid == -1) {
+               pb_log("%s: fork failed: %s\n", __func__, strerror(errno));
+               return -1;
+       }
+
+       if (pid == 0) {
+               execl(pb_system_apps.umount, pb_system_apps.umount,
+                                               dev->mount_path, NULL);
+               exit(EXIT_FAILURE);
+       }
+
+       if (waitpid(pid, &status, 0) == -1) {
+               pb_log("%s: waitpid failed: %s\n", __func__,
+                               strerror(errno));
+               return -1;
+       }
+
+       if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
+               return -1;
+
+       pb_rmdir_recursive(mount_base(), dev->mount_path);
+
+       return 0;
+}
+
+static struct discover_device *find_device(struct device_handler *handler,
+               const char *id)
+{
+       struct discover_device *dev;
+       unsigned int i;
+
+       for (i = 0; i < handler->n_devices; i++) {
+               dev = handler->devices[i];
+               if (!strcmp(dev->device->id, id))
+                       return dev;
+       }
+
+       return NULL;
+}
+
+static int destroy_device(void *arg)
+{
+       struct discover_device *dev = arg;
+
+       umount_device(dev);
+
+       return 0;
+}
+
+static struct discover_device *discover_device_create(
+               struct device_handler *handler,
+               struct discover_context *ctx,
+               struct event *event)
+{
+       struct discover_device *dev;
+       const char *devname;
+
+       dev = find_device(handler, event->device);
+       if (dev)
+               return dev;
+
+       dev = talloc_zero(ctx, struct discover_device);
+       dev->device = talloc_zero(dev, struct device);
+       list_init(&dev->boot_options);
+
+       devname = event_get_param(ctx->event, "DEVNAME");
+       if (devname)
+               dev->device_path = talloc_strdup(dev, devname);
+
+       dev->device->id = talloc_strdup(dev, event->device);
+
+       talloc_set_destructor(dev, destroy_device);
+
+       return dev;
+}
+
+struct discover_boot_option *discover_boot_option_create(
+               struct discover_context *ctx,
+               struct discover_device *device)
+{
+       struct discover_boot_option *opt;
+
+       opt = talloc_zero(ctx, struct discover_boot_option);
+       opt->option = talloc_zero(opt, struct boot_option);
+       opt->device = device;
+
+       return opt;
+}
+
+
+static int handle_add_udev_event(struct device_handler *handler,
+               struct event *event)
+{
+       struct discover_context *ctx;
+       struct discover_device *dev;
+       const char *param;
+       int rc;
+
+       /* create our context */
+       ctx = talloc(handler, struct discover_context);
+       ctx->event = event;
+       list_init(&ctx->boot_options);
+
+       /* create our top-level device */
+       dev = discover_device_create(handler, ctx, event);
 
-       struct device *devices;
-       int n_devices;
+       ctx->device = dev;
+
+       /* try to parse UUID and labels */
+       param = event_get_param(ctx->event, "ID_FS_UUID");
+       if (param)
+               dev->uuid = talloc_strdup(dev, param);
+
+       param = event_get_param(ctx->event, "ID_FS_LABEL");
+       if (param)
+               dev->label = talloc_strdup(dev, param);
+
+       rc = mount_device(dev);
+       if (rc) {
+               talloc_free(ctx);
+               return 0;
+       }
+
+       /* run the parsers. This will populate the ctx's boot_option list. */
+       iterate_parsers(ctx);
+
+       /* add discovered stuff to the handler */
+       context_commit(handler, ctx);
+
+       talloc_free(ctx);
+
+       return 0;
+}
+
+static int handle_remove_udev_event(struct device_handler *handler,
+               struct event *event)
+{
+       struct discover_device *dev;
+
+       dev = find_device(handler, event->device);
+       if (!dev)
+               return 0;
+
+       /* remove device from handler device array */
+       device_handler_remove(handler, dev);
+
+       return 0;
+}
+
+static int handle_add_user_event(struct device_handler *handler,
+               struct event *event)
+{
+       struct discover_context *ctx;
+       struct discover_device *dev;
+       int rc;
+
+       assert(event->device);
+
+       ctx = talloc(handler, struct discover_context);
+       ctx->event = event;
+       list_init(&ctx->boot_options);
+
+       dev = discover_device_create(handler, ctx, event);
+       ctx->device = dev;
+
+       rc = parse_user_event(ctx, event);
+
+       if (!rc)
+               context_commit(handler, ctx);
+
+       return rc;
+}
+
+static int handle_remove_user_event(struct device_handler *handler,
+               struct event *event)
+{
+       struct discover_device *dev = find_device(handler, event->device);
+
+       if (!dev)
+               return 0;
+
+       /* remove device from handler device array */
+       device_handler_remove(handler, dev);
+
+       return 0;
+}
+
+typedef int (*event_handler)(struct device_handler *, struct event *);
+
+static event_handler handlers[EVENT_TYPE_MAX][EVENT_ACTION_MAX] = {
+       [EVENT_TYPE_UDEV] = {
+               [EVENT_ACTION_ADD]      = handle_add_udev_event,
+               [EVENT_ACTION_REMOVE]   = handle_remove_udev_event,
+       },
+       [EVENT_TYPE_USER] = {
+               [EVENT_ACTION_ADD]      = handle_add_user_event,
+               [EVENT_ACTION_REMOVE]   = handle_remove_user_event,
+       }
 };
 
-struct device_handler *device_handler_init(struct discover_server *server)
+int device_handler_event(struct device_handler *handler,
+               struct event *event)
+{
+       if (event->type >= EVENT_TYPE_MAX ||
+                       event->action >= EVENT_ACTION_MAX ||
+                       !handlers[event->type][event->action]) {
+               pb_log("%s unknown type/action: %d/%d\n", __func__,
+                               event->type, event->action);
+               return 0;
+       }
+
+       return handlers[event->type][event->action](handler, event);
+}
+
+struct device_handler *device_handler_init(struct discover_server *server,
+               int dry_run)
 {
        struct device_handler *handler;
 
        handler = talloc(NULL, struct device_handler);
        handler->devices = NULL;
        handler->n_devices = 0;
+       handler->server = server;
+       handler->dry_run = dry_run;
+
+       /* set up our mount point base */
+       pb_mkdir_recursive(mount_base());
+
+       parser_init();
 
        return handler;
 }
 
-void device_handler_destroy(struct device_handler *devices)
+void device_handler_destroy(struct device_handler *handler)
 {
-       talloc_free(devices);
+       talloc_free(handler);
 }
 
-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 int device_match_path(struct discover_device *dev, const char *path)
+{
+       return !strcmp(dev->device_path, path);
+}
 
-static struct device device = {
-       .id = "1",
-       .name = "meep",
-       .description = "meep description",
-       .icon_file = "meep.png",
-       .n_options = 1,
-       .options = options,
-};
+static int device_match_uuid(struct discover_device *dev, const char *uuid)
+{
+       return dev->uuid && !strcmp(dev->uuid, uuid);
+}
 
-int device_handler_get_current_devices(struct device_handler *handler,
-               struct device **devices)
+static int device_match_label(struct discover_device *dev, const char *label)
+{
+       return dev->label && !strcmp(dev->label, label);
+}
 
+static int device_match_id(struct discover_device *dev, const char *id)
 {
-       *devices = &device;
-       return 1;
+       return !strcmp(dev->device->id, id);
 }
 
+static struct discover_device *device_lookup(
+               struct device_handler *device_handler,
+               int (match_fn)(struct discover_device *, const char *),
+               const char *str)
+{
+       struct discover_device *dev;
+       unsigned int i;
 
-int device_handler_event(struct device_handler *handler,
-               struct udev_event *event)
+       if (!str)
+               return NULL;
+
+       for (i = 0; i < device_handler->n_devices; i++) {
+               dev = device_handler->devices[i];
+
+               if (match_fn(dev, str))
+                       return dev;
+       }
+
+       return NULL;
+}
+
+struct discover_device *device_lookup_by_name(struct device_handler *handler,
+               const char *name)
 {
-       return 0;
+       struct discover_device *dev;
+       char *path;
+
+       if (strncmp(name, "/dev/", strlen("/dev/")))
+               path = talloc_asprintf(NULL, "/dev/%s", name);
+       else
+               path = talloc_strdup(NULL, name);
+
+       dev = device_lookup_by_path(handler, path);
+
+       talloc_free(path);
+
+       return dev;
+}
+
+struct discover_device *device_lookup_by_path(
+               struct device_handler *device_handler,
+               const char *path)
+{
+       return device_lookup(device_handler, device_match_path, path);
+}
+
+struct discover_device *device_lookup_by_uuid(
+               struct device_handler *device_handler,
+               const char *uuid)
+{
+       return device_lookup(device_handler, device_match_uuid, uuid);
+}
+
+struct discover_device *device_lookup_by_label(
+               struct device_handler *device_handler,
+               const char *label)
+{
+       return device_lookup(device_handler, device_match_label, label);
+}
+
+struct discover_device *device_lookup_by_id(
+               struct device_handler *device_handler,
+               const char *id)
+{
+       return device_lookup(device_handler, device_match_id, id);
+}
+
+static struct discover_boot_option *find_boot_option_by_id(
+               struct device_handler *handler, const char *id)
+{
+       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)
+                       if (!strcmp(opt->option->id, id))
+                               return opt;
+       }
+
+       return NULL;
+}
+
+void device_handler_boot(struct device_handler *handler,
+               struct boot_command *cmd)
+{
+       struct discover_boot_option *opt;
+
+       opt = find_boot_option_by_id(handler, cmd->option_id);
+
+       boot(handler, opt, cmd, handler->dry_run);
 }