From e21b7229ff776891443fe3200ebf4648f3f2940b Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Thu, 11 Oct 2018 10:01:41 +0200 Subject: [PATCH] import: rerrange tarball/fs imports that have a single top-level directory containing the OS tree Let's handle tarball imports nicer that have a single top-level directory containing the OS tree: let's move everything down during import, so that the OS tree is ready to use automatically. Fixes: #2116 --- src/import/import-common.c | 109 +++++++++++++++++++++++++++++++++++++ src/import/import-common.h | 2 + src/import/import-fs.c | 4 ++ src/import/import-tar.c | 4 ++ 4 files changed, 119 insertions(+) diff --git a/src/import/import-common.c b/src/import/import-common.c index e2de2c2dd0..24cab484a2 100644 --- a/src/import/import-common.c +++ b/src/import/import-common.c @@ -5,10 +5,15 @@ #include #include +#include "alloc-util.h" #include "btrfs-util.h" #include "capability-util.h" +#include "dirent-util.h" #include "fd-util.h" +#include "fileio.h" +#include "fs-util.h" #include "import-common.h" +#include "os-util.h" #include "process-util.h" #include "signal-util.h" #include "util.h" @@ -147,3 +152,107 @@ int import_fork_tar_c(const char *path, pid_t *ret) { return TAKE_FD(pipefd[0]); } + +int import_mangle_os_tree(const char *path) { + _cleanup_closedir_ DIR *d = NULL, *cd = NULL; + _cleanup_free_ char *child = NULL, *t = NULL; + const char *joined; + struct dirent *de; + int r; + + assert(path); + + /* Some tarballs contain a single top-level directory that contains the actual OS directory tree. Try to + * recognize this, and move the tree one level up. */ + + r = path_is_os_tree(path); + if (r < 0) + return log_error_errno(r, "Failed to determine whether '%s' is an OS tree: %m", path); + if (r > 0) { + log_debug("Directory tree '%s' is a valid OS tree.", path); + return 0; + } + + log_debug("Directory tree '%s' is not recognizable as OS tree, checking whether to rearrange it.", path); + + d = opendir(path); + if (!d) + return log_error_errno(r, "Failed to open directory '%s': %m", path); + + errno = 0; + de = readdir_no_dot(d); + if (!de) { + if (errno != 0) + return log_error_errno(errno, "Failed to iterate through directory '%s': %m", path); + + log_debug("Directory '%s' is empty, leaving it as it is.", path); + return 0; + } + + child = strdup(de->d_name); + if (!child) + return log_oom(); + + errno = 0; + de = readdir_no_dot(d); + if (de) { + if (errno != 0) + return log_error_errno(errno, "Failed to iterate through directory '%s': %m", path); + + log_debug("Directory '%s' does not look like a directory tree, and has multiple children, leaving as it is.", path); + return 0; + } + + joined = strjoina(path, "/", child); + r = path_is_os_tree(joined); + if (r == -ENOTDIR) { + log_debug("Directory '%s' does not look like a directory tree, and contains a single regular file only, leaving as it is.", path); + return 0; + } + if (r < 0) + return log_error_errno(r, "Failed to determine whether '%s' is an OS tree: %m", joined); + if (r == 0) { + log_debug("Neither '%s' nor '%s' is a valid OS tree, leaving them as they are.", path, joined); + return 0; + } + + /* Nice, we have checked now: + * + * 1. The top-level directory does not qualify as OS tree + * 1. The top-level directory only contains one item + * 2. That item is a directory + * 3. And that directory qualifies as OS tree + * + * Let's now rearrange things, moving everything in the inner directory one level up */ + + cd = xopendirat(dirfd(d), child, O_NOFOLLOW); + if (!cd) + return log_error_errno(errno, "Can't open directory '%s': %m", joined); + + log_info("Rearranging '%s', moving OS tree one directory up.", joined); + + /* Let's rename the child to an unguessable name so that we can be sure all files contained in it can be + * safely moved up and won't collide with the name. */ + r = tempfn_random(child, NULL, &t); + if (r < 0) + return log_oom(); + r = rename_noreplace(dirfd(d), child, dirfd(d), t); + if (r < 0) + return log_error_errno(r, "Unable to rename '%s' to '%s/%s': %m", joined, path, t); + + FOREACH_DIRENT_ALL(de, cd, return log_error_errno(errno, "Failed to iterate through directory '%s': %m", joined)) { + if (dot_or_dot_dot(de->d_name)) + continue; + + r = rename_noreplace(dirfd(cd), de->d_name, dirfd(d), de->d_name); + if (r < 0) + return log_error_errno(r, "Unable to move '%s/%s/%s' to '%s/%s': %m", path, t, de->d_name, path, de->d_name); + } + + if (unlinkat(dirfd(d), t, AT_REMOVEDIR) < 0) + return log_error_errno(errno, "Failed to remove temporary directory '%s/%s': %m", path, t); + + log_info("Successfully rearranged OS tree."); + + return 0; +} diff --git a/src/import/import-common.h b/src/import/import-common.h index 34ed829de0..94d224f412 100644 --- a/src/import/import-common.h +++ b/src/import/import-common.h @@ -8,3 +8,5 @@ int import_make_read_only(const char *path); int import_fork_tar_c(const char *path, pid_t *ret); int import_fork_tar_x(const char *path, pid_t *ret); + +int import_mangle_os_tree(const char *path); diff --git a/src/import/import-fs.c b/src/import/import-fs.c index 3836f87570..bc2e631e7b 100644 --- a/src/import/import-fs.c +++ b/src/import/import-fs.c @@ -192,6 +192,10 @@ static int import_fs(int argc, char *argv[], void *userdata) { goto finish; } + r = import_mangle_os_tree(temp_path); + if (r < 0) + goto finish; + (void) import_assign_pool_quota_and_warn(temp_path); if (arg_read_only) { diff --git a/src/import/import-tar.c b/src/import/import-tar.c index 0399b03747..a164417de0 100644 --- a/src/import/import-tar.c +++ b/src/import/import-tar.c @@ -184,6 +184,10 @@ static int tar_import_finish(TarImport *i) { return r; } + r = import_mangle_os_tree(i->temp_path); + if (r < 0) + return r; + if (i->read_only) { r = import_make_read_only(i->temp_path); if (r < 0)