From 19f4f86bfed21c5326ed2acebe1163f3a83e832b Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 04:25:50 +0200 Subject: Adding upstream version 241. Signed-off-by: Daniel Baumann --- src/shared/os-util.c | 117 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 117 insertions(+) create mode 100644 src/shared/os-util.c (limited to 'src/shared/os-util.c') diff --git a/src/shared/os-util.c b/src/shared/os-util.c new file mode 100644 index 0000000..b2d5ce3 --- /dev/null +++ b/src/shared/os-util.c @@ -0,0 +1,117 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +#include "alloc-util.h" +#include "env-file.h" +#include "fd-util.h" +#include "fs-util.h" +#include "macro.h" +#include "os-util.h" +#include "string-util.h" +#include "strv.h" + +int path_is_os_tree(const char *path) { + int r; + + assert(path); + + /* Does the path exist at all? If not, generate an error immediately. This is useful so that a missing root dir + * always results in -ENOENT, and we can properly distuingish the case where the whole root doesn't exist from + * the case where just the os-release file is missing. */ + if (laccess(path, F_OK) < 0) + return -errno; + + /* We use {/etc|/usr/lib}/os-release as flag file if something is an OS */ + r = open_os_release(path, NULL, NULL); + if (r == -ENOENT) /* We got nothing */ + return 0; + if (r < 0) + return r; + + return 1; +} + +int open_os_release(const char *root, char **ret_path, int *ret_fd) { + _cleanup_free_ char *q = NULL; + const char *p; + int k; + + FOREACH_STRING(p, "/etc/os-release", "/usr/lib/os-release") { + k = chase_symlinks(p, root, CHASE_PREFIX_ROOT|(ret_fd ? CHASE_OPEN : 0), (ret_path ? &q : NULL)); + if (k != -ENOENT) + break; + } + if (k < 0) + return k; + + if (ret_fd) { + int real_fd; + + /* Convert the O_PATH fd into a proper, readable one */ + real_fd = fd_reopen(k, O_RDONLY|O_CLOEXEC|O_NOCTTY); + safe_close(k); + if (real_fd < 0) + return real_fd; + + *ret_fd = real_fd; + } + + if (ret_path) + *ret_path = TAKE_PTR(q); + + return 0; +} + +int fopen_os_release(const char *root, char **ret_path, FILE **ret_file) { + _cleanup_free_ char *p = NULL; + _cleanup_close_ int fd = -1; + FILE *f; + int r; + + if (!ret_file) + return open_os_release(root, ret_path, NULL); + + r = open_os_release(root, ret_path ? &p : NULL, &fd); + if (r < 0) + return r; + + f = fdopen(fd, "r"); + if (!f) + return -errno; + fd = -1; + + *ret_file = f; + + if (ret_path) + *ret_path = TAKE_PTR(p); + + return 0; +} + +int parse_os_release(const char *root, ...) { + _cleanup_fclose_ FILE *f = NULL; + _cleanup_free_ char *p = NULL; + va_list ap; + int r; + + r = fopen_os_release(root, &p, &f); + if (r < 0) + return r; + + va_start(ap, root); + r = parse_env_filev(f, p, ap); + va_end(ap); + + return r; +} + +int load_os_release_pairs(const char *root, char ***ret) { + _cleanup_fclose_ FILE *f = NULL; + _cleanup_free_ char *p = NULL; + int r; + + r = fopen_os_release(root, &p, &f); + if (r < 0) + return r; + + return load_env_file_pairs(f, p, ret); +} -- cgit v1.2.3