Add device handler cleanup

[petitboot] / discover / device-handler.c

diff --git a/discover/device-handler.c b/discover/device-handler.c
index 5d40ebe99642711e6f17d9f4b2d113e94f7bfc4c..90d92968bd024fd5e7dd38ada6c8eb9a2840abab 100644 (file)
--- a/discover/device-handler.c
+++ b/discover/device-handler.c
@@ -7,6 +7,7 @@
 #include <sys/wait.h>
 
 #include <talloc/talloc.h>
+#include <list/list.h>
 #include <pb-protocol/pb-protocol.h>
 
 #include "device-handler.h"
@@ -16,6 +17,8 @@
 
 #define MOUNT_BIN "/bin/mount"
 
+#define UMOUNT_BIN "/bin/umount"
+
 struct device_handler {
        struct discover_server *server;
 
@@ -24,12 +27,15 @@ struct device_handler {
 };
 
 struct discover_context {
+       char *id;
        char *device_path;
        char *mount_path;
        struct udev_event *event;
        struct device *device;
        char **links;
        int n_links;
+
+       struct list_item list;
 };
 
 struct mount_map {
@@ -37,6 +43,7 @@ struct mount_map {
        char *mount_point;
 };
 
+static struct list contexts;
 
 static struct boot_option options[] = {
        {
@@ -110,6 +117,33 @@ static int mkdir_recursive(const char *dir)
        return 0;
 }
 
+static int rmdir_recursive(const char *base, const char *dir)
+{
+       char *cur, *pos;
+
+       /* sanity check: make sure that dir is within base */
+       if (strncmp(base, dir, strlen(base)))
+               return -1;
+
+       cur = talloc_strdup(NULL, dir);
+
+       while (strcmp(base, dir)) {
+
+               rmdir(dir);
+
+               /* null-terminate at the last slash */
+               pos = strrchr(dir, '/');
+               if (!pos)
+                       break;
+
+               *pos = '\0';
+       }
+
+       talloc_free(cur);
+
+       return 0;
+}
+
 static void setup_device_links(struct discover_context *ctx)
 {
        struct link {
@@ -133,7 +167,7 @@ static void setup_device_links(struct discover_context *ctx)
                const char *value;
 
                value = udev_event_param(ctx->event, link->env);
-               if (!value)
+               if (!value || !*value)
                        continue;
 
                enc = encode_label(ctx, value);
@@ -162,10 +196,17 @@ static void setup_device_links(struct discover_context *ctx)
        }
 }
 
+static void remove_device_links(struct discover_context *ctx)
+{
+       int i;
+
+       for (i = 0; i < ctx->n_links; i++)
+               unlink(ctx->links[i]);
+}
+
 static int mount_device(struct discover_context *ctx)
 {
        const char *mountpoint;
-       struct stat statbuf;
        int status;
        pid_t pid;
 
@@ -174,24 +215,14 @@ static int mount_device(struct discover_context *ctx)
                ctx->mount_path = talloc_strdup(ctx, mountpoint);
        }
 
-       if (stat(ctx->mount_path, &statbuf)) {
-               if (mkdir(ctx->mount_path, 0755)) {
-                       pb_log("couldn't create mount directory %s: %s\n",
-                                       ctx->mount_path, strerror(errno));
-                       return -1;
-               }
-       } else {
-               if (!S_ISDIR(statbuf.st_mode)) {
-                       pb_log("mountpoint %s exists, but isn't a directory\n",
-                                       ctx->mount_path);
-                       return -1;
-               }
-       }
+       if (mkdir_recursive(ctx->mount_path))
+               pb_log("couldn't create mount directory %s: %s\n",
+                               ctx->mount_path, strerror(errno));
 
        pid = fork();
        if (pid == -1) {
                pb_log("%s: fork failed: %s\n", __func__, strerror(errno));
-               return -1;
+               goto out_rmdir;
        }
 
        if (pid == 0) {
@@ -200,6 +231,41 @@ static int mount_device(struct discover_context *ctx)
                exit(EXIT_FAILURE);
        }
 
+       if (waitpid(pid, &status, 0) == -1) {
+               pb_log("%s: waitpid failed: %s\n", __func__,
+                               strerror(errno));
+               goto out_rmdir;
+       }
+
+       if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
+               goto out_rmdir;
+
+       setup_device_links(ctx);
+       return 0;
+
+out_rmdir:
+       rmdir_recursive(mount_base(), ctx->mount_path);
+       return -1;
+}
+
+static int umount_device(struct discover_context *ctx)
+{
+       int status;
+       pid_t pid;
+
+       remove_device_links(ctx);
+
+       pid = fork();
+       if (pid == -1) {
+               pb_log("%s: fork failed: %s\n", __func__, strerror(errno));
+               return -1;
+       }
+
+       if (pid == 0) {
+               execl(UMOUNT_BIN, UMOUNT_BIN, ctx->mount_path, NULL);
+               exit(EXIT_FAILURE);
+       }
+
        if (waitpid(pid, &status, 0) == -1) {
                pb_log("%s: waitpid failed: %s\n", __func__,
                                strerror(errno));
@@ -209,7 +275,31 @@ static int mount_device(struct discover_context *ctx)
        if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
                return -1;
 
-       setup_device_links(ctx);
+       rmdir_recursive(mount_base(), ctx->mount_path);
+
+       return 0;
+}
+
+static struct discover_context *find_context(const char *id)
+{
+       struct discover_context *ctx;
+
+       list_for_each_entry(&contexts, ctx, list) {
+               if (!strcmp(ctx->id, id))
+                       return ctx;
+       }
+
+       return NULL;
+}
+
+
+static int destroy_context(void *arg)
+{
+       struct discover_context *ctx = arg;
+
+       list_remove(&ctx->list);
+       umount_device(ctx);
+
        return 0;
 }
 
@@ -227,6 +317,8 @@ static int handle_add_event(struct device_handler *handler,
        ctx->links = NULL;
        ctx->n_links = 0;
 
+       ctx->id = talloc_strdup(ctx, event->device);
+
        devname = udev_event_param(ctx->event, "DEVNAME");
        if (!devname) {
                pb_log("no devname for %s?\n", event->device);
@@ -242,7 +334,9 @@ static int handle_add_event(struct device_handler *handler,
                return 0;
        }
 
-       talloc_free(ctx);
+       list_add(&contexts, &ctx->list);
+
+       talloc_set_destructor(ctx, destroy_context);
 
        return 0;
 }
@@ -250,6 +344,14 @@ static int handle_add_event(struct device_handler *handler,
 static int handle_remove_event(struct device_handler *handler,
                struct udev_event *event)
 {
+       struct discover_context *ctx;
+
+       ctx = find_context(event->device);
+       if (!ctx)
+               return 0;
+
+       talloc_free(ctx);
+
        return 0;
 }
 
@@ -279,6 +381,8 @@ struct device_handler *device_handler_init(struct discover_server *server)
        handler->devices = NULL;
        handler->n_devices = 0;
 
+       list_init(&contexts);
+
        /* set up our mount point base */
        mkdir_recursive(mount_base());
 
@@ -287,6 +391,11 @@ struct device_handler *device_handler_init(struct discover_server *server)
 
 void device_handler_destroy(struct device_handler *devices)
 {
+       struct discover_context *ctx, *n;
+
        talloc_free(devices);
+
+       list_for_each_entry_safe(&contexts, ctx, n, list)
+               talloc_free(ctx);
 }