X-Git-Url: http://git.ozlabs.org/?p=petitboot;a=blobdiff_plain;f=discover%2Fdevice-handler.c;h=1f8938f295b322e68b2df19fb7eeadd8146b1ca1;hp=0e902df6b86ed4c1805868617cf7db85abb08bf7;hb=b118597194815910897ccf86d77b8b5a066adf5a;hpb=94af239b00f547fb5daef88b16fecdfb0146691b diff --git a/discover/device-handler.c b/discover/device-handler.c index 0e902df..1f8938f 100644 --- a/discover/device-handler.c +++ b/discover/device-handler.c @@ -1,31 +1,50 @@ +#include +#include +#include +#include +#include +#include + #include +#include #include #include "device-handler.h" +#include "udev.h" +#include "log.h" +#include "paths.h" + +#define MOUNT_BIN "/bin/mount" + +#define UMOUNT_BIN "/bin/umount" struct device_handler { struct discover_server *server; struct device *devices; int n_devices; + + struct list contexts; }; -struct device_handler *device_handler_init(struct discover_server *server) -{ - struct device_handler *handler; +struct discover_context { + char *id; + char *device_path; + char *mount_path; + struct udev_event *event; + struct device *device; + char **links; + int n_links; - handler = talloc(NULL, struct device_handler); - handler->devices = NULL; - handler->n_devices = 0; + struct list_item list; +}; - return handler; -} +struct mount_map { + char *device_path; + char *mount_point; +}; -void device_handler_destroy(struct device_handler *devices) -{ - talloc_free(devices); -} static struct boot_option options[] = { { @@ -42,8 +61,6 @@ static struct device device = { .name = "meep", .description = "meep description", .icon_file = "meep.png", - .n_options = 1, - .options = options, }; int device_handler_get_current_devices(struct device_handler *handler, @@ -54,9 +71,333 @@ int device_handler_get_current_devices(struct device_handler *handler, return 1; } +static int mkdir_recursive(const char *dir) +{ + struct stat statbuf; + char *str, *sep; + int mode = 0755; + + if (!*dir) + return 0; + + if (!stat(dir, &statbuf)) { + if (!S_ISDIR(statbuf.st_mode)) { + pb_log("%s: %s exists, but isn't a directory\n", + __func__, dir); + return -1; + } + return 0; + } + + str = talloc_strdup(NULL, dir); + sep = strchr(*str == '/' ? str + 1 : str, '/'); + + while (1) { + + /* terminate the path at sep */ + if (sep) + *sep = '\0'; + + if (mkdir(str, mode) && errno != EEXIST) { + pb_log("mkdir(%s): %s\n", str, strerror(errno)); + return -1; + } + + if (!sep) + break; + + /* reset dir to the full path */ + strcpy(str, dir); + sep = strchr(sep + 1, '/'); + } + + talloc_free(str); + + return 0; +} + +static int rmdir_recursive(const char *base, const char *dir) +{ + char *cur, *pos; -int device_handler_event(struct device_handler *handler, + /* 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 { + char *env, *dir; + } *link, links[] = { + { + .env = "ID_FS_UUID", + .dir = "disk/by-uuid" + }, + { + .env = "ID_FS_LABEL", + .dir = "disk/by-label" + }, + { + .env = NULL + } + }; + + for (link = links; link->env; link++) { + char *enc, *dir, *path; + const char *value; + + value = udev_event_param(ctx->event, link->env); + if (!value || !*value) + continue; + + enc = encode_label(ctx, value); + dir = join_paths(ctx, mount_base(), link->dir); + path = join_paths(ctx, dir, value); + + if (!mkdir_recursive(dir)) { + unlink(path); + if (symlink(ctx->mount_path, path)) { + pb_log("symlink(%s,%s): %s\n", + ctx->mount_path, path, + strerror(errno)); + talloc_free(path); + } else { + int i = ctx->n_links++; + ctx->links = talloc_realloc(ctx, + ctx->links, char *, + ctx->n_links); + ctx->links[i] = path; + } + + } + + talloc_free(dir); + talloc_free(enc); + } +} + +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; + int status; + pid_t pid; + + if (!ctx->mount_path) { + mountpoint = mountpoint_for_device(ctx->device_path); + ctx->mount_path = talloc_strdup(ctx, mountpoint); + } + + 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)); + goto out_rmdir; + } + + if (pid == 0) { + execl(MOUNT_BIN, MOUNT_BIN, ctx->device_path, ctx->mount_path, + "-o", "ro", NULL); + 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)); + return -1; + } + + if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) + return -1; + + rmdir_recursive(mount_base(), ctx->mount_path); + + return 0; +} + +static struct discover_context *find_context(struct device_handler *handler, + const char *id) +{ + struct discover_context *ctx; + + list_for_each_entry(&handler->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; +} + +static int handle_add_event(struct device_handler *handler, + struct udev_event *event) +{ + struct discover_context *ctx; + const char *devname; + int rc; + + /* create our context */ + ctx = talloc(handler, struct discover_context); + ctx->event = event; + ctx->mount_path = NULL; + 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); + return 0; + } + + ctx->device_path = talloc_strdup(ctx, devname); + + rc = mount_device(ctx); + if (rc) { + pb_log("mount_device failed for %s\n", event->device); + talloc_free(ctx); + return 0; + } + + list_add(&handler->contexts, &ctx->list); + + talloc_set_destructor(ctx, destroy_context); + + return 0; +} + +static int handle_remove_event(struct device_handler *handler, struct udev_event *event) { + struct discover_context *ctx; + + ctx = find_context(handler, event->device); + if (!ctx) + return 0; + + talloc_free(ctx); + return 0; } + +int device_handler_event(struct device_handler *handler, + struct udev_event *event) +{ + int rc; + + switch (event->action) { + case UDEV_ACTION_ADD: + rc = handle_add_event(handler, event); + break; + + case UDEV_ACTION_REMOVE: + rc = handle_remove_event(handler, event); + break; + } + + return rc; +} + +struct device_handler *device_handler_init(struct discover_server *server) +{ + struct device_handler *handler; + int i; + + handler = talloc(NULL, struct device_handler); + handler->devices = NULL; + handler->n_devices = 0; + + list_init(&handler->contexts); + + /* set up our mount point base */ + mkdir_recursive(mount_base()); + + /* setup out test objects */ + list_init(&device.boot_options); + + for (i = 0; i < sizeof(options) / sizeof(options[0]); i++) + list_add(&device.boot_options, &options[i].list); + + return handler; +} + +void device_handler_destroy(struct device_handler *handler) +{ + talloc_free(handler); +} +