From 2cefb09ff69c3595e98c55f0da1bd137c612276c Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Mon, 26 Mar 2018 16:32:40 +0200 Subject: os-util: add helpers for finding /etc/os-release Place this new helpers in a new source file os-util.[ch], and move the existing and related call path_is_os_tree() to it as well. --- src/basic/meson.build | 3 +- src/basic/os-util.c | 117 ++++++++++++++++++++++++++++++++++++++++++++++ src/basic/os-util.h | 12 +++++ src/basic/stat-util.c | 26 ----------- src/basic/stat-util.h | 1 - src/test/meson.build | 11 +++++ src/test/test-os-util.c | 22 +++++++++ src/test/test-stat-util.c | 7 --- 8 files changed, 164 insertions(+), 35 deletions(-) create mode 100644 src/basic/os-util.c create mode 100644 src/basic/os-util.h create mode 100644 src/test/test-os-util.c diff --git a/src/basic/meson.build b/src/basic/meson.build index 5eef906d4..cd823c0f9 100644 --- a/src/basic/meson.build +++ b/src/basic/meson.build @@ -132,6 +132,8 @@ # ordered-set.h # pager.c # pager.h +# os-util.c +# os-util.h # parse-util.c # parse-util.h # path-util.c @@ -164,7 +166,6 @@ # securebits.h # selinux-util.c # selinux-util.h -# set.c # set.h # sigbus.c # sigbus.h diff --git a/src/basic/os-util.c b/src/basic/os-util.c new file mode 100644 index 000000000..a215b631d --- /dev/null +++ b/src/basic/os-util.c @@ -0,0 +1,117 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +//#include "alloc-util.h" +//#include "fd-util.h" +//#include "fs-util.h" +//#include "macro.h" +//#include "os-util.h" +//#include "strv.h" +//#include "fileio.h" +//#include "string-util.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, "re"); + 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, NEWLINE, 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, NEWLINE, ret); +} diff --git a/src/basic/os-util.h b/src/basic/os-util.h new file mode 100644 index 000000000..93eea24eb --- /dev/null +++ b/src/basic/os-util.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ +#pragma once + +//#include + +int path_is_os_tree(const char *path); + +int open_os_release(const char *root, char **ret_path, int *ret_fd); +int fopen_os_release(const char *root, char **ret_path, FILE **ret_file); + +int parse_os_release(const char *root, ...); +int load_os_release_pairs(const char *root, char ***ret); diff --git a/src/basic/stat-util.c b/src/basic/stat-util.c index a1628efd9..d88f97fdf 100644 --- a/src/basic/stat-util.c +++ b/src/basic/stat-util.c @@ -139,33 +139,7 @@ int path_is_read_only_fs(const char *path) { } #if 0 /// UNNEEDED by elogind -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 /usr/lib/os-release as flag file if something is an OS */ - r = chase_symlinks("/usr/lib/os-release", path, CHASE_PREFIX_ROOT, NULL); - if (r == -ENOENT) { - - /* Also check for the old location in /etc, just in case. */ - r = chase_symlinks("/etc/os-release", path, CHASE_PREFIX_ROOT, NULL); - if (r == -ENOENT) - return 0; /* We got nothing */ - } - if (r < 0) - return r; - - return 1; -} #endif // 0 - int files_same(const char *filea, const char *fileb, int flags) { struct stat a, b; diff --git a/src/basic/stat-util.h b/src/basic/stat-util.h index 0a30c510a..325caf445 100644 --- a/src/basic/stat-util.h +++ b/src/basic/stat-util.h @@ -42,7 +42,6 @@ int null_or_empty_fd(int fd); int path_is_read_only_fs(const char *path); #if 0 /// UNNEEDED by elogind -int path_is_os_tree(const char *path); #endif // 0 int files_same(const char *filea, const char *fileb, int flags); diff --git a/src/test/meson.build b/src/test/meson.build index 833634ffa..8d694b379 100644 --- a/src/test/meson.build +++ b/src/test/meson.build @@ -264,6 +264,10 @@ tests += [ [], []], + [['src/test/test-os-util.c'], + [], + []], + [['src/test/test-escape.c'], [], []], @@ -956,6 +960,7 @@ tests += [ # 'src/libsystemd-network/dhcp-internal.h'], # [libshared, # libelogind_network], +# libsystemd_network], # []], # # [['src/libsystemd-network/test-sd-dhcp-lease.c', @@ -970,11 +975,13 @@ tests += [ # 'src/systemd/sd-dhcp-client.h'], # [libshared, # libelogind_network], +# libsystemd_network], # []], # # [['src/libelogind-network/test-dhcp-server.c'], # [libshared, # libelogind_network], +# libsystemd_network], # []], # # [['src/libsystemd-network/test-ipv4ll.c', @@ -982,12 +989,14 @@ tests += [ # 'src/systemd/sd-ipv4ll.h'], # [libshared, # libelogind_network], +# libsystemd_network], # []], # # [['src/libelogind-network/test-ipv4ll-manual.c', # 'src/systemd/sd-ipv4ll.h'], # [libshared, # libelogind_network], +# libsystemd_network], # [], # '', 'manual'], # @@ -1006,6 +1015,7 @@ tests += [ # 'src/systemd/sd-ndisc.h'], # [libshared, # libelogind_network], +# libsystemd_network], # []], # # [['src/libsystemd-network/test-ndisc-ra.c', @@ -1022,6 +1032,7 @@ tests += [ # 'src/systemd/sd-dhcp6-client.h'], # [libshared, # libelogind_network], +# libsystemd_network], # []], # # [['src/libelogind-network/test-lldp.c'], diff --git a/src/test/test-os-util.c b/src/test/test-os-util.c new file mode 100644 index 000000000..1e78f352a --- /dev/null +++ b/src/test/test-os-util.c @@ -0,0 +1,22 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +//#include + +//#include "log.h" +//#include "os-util.h" + +static void test_path_is_os_tree(void) { + assert_se(path_is_os_tree("/") > 0); + assert_se(path_is_os_tree("/etc") == 0); + assert_se(path_is_os_tree("/idontexist") == -ENOENT); +} + +int main(int argc, char *argv[]) { + log_set_max_level(LOG_DEBUG); + log_parse_environment(); + log_open(); + + test_path_is_os_tree(); + + return 0; +} diff --git a/src/test/test-stat-util.c b/src/test/test-stat-util.c index 3d8d911ac..52142a53f 100644 --- a/src/test/test-stat-util.c +++ b/src/test/test-stat-util.c @@ -53,12 +53,6 @@ static void test_is_symlink(void) { unlink(name_link); } -static void test_path_is_os_tree(void) { - assert_se(path_is_os_tree("/") > 0); - assert_se(path_is_os_tree("/etc") == 0); - assert_se(path_is_os_tree("/idontexist") == -ENOENT); -} - static void test_path_is_fs_type(void) { /* run might not be a mount point in build chroots */ if (path_is_mount_point("/run", NULL, AT_SYMLINK_FOLLOW) > 0) { @@ -84,7 +78,6 @@ int main(int argc, char *argv[]) { test_files_same(); #if 0 /// UNNEEDED by elogind test_is_symlink(); - test_path_is_os_tree(); test_path_is_fs_type(); test_path_is_temporary_fs(); #endif // 0 -- cgit v1.2.3