diff options
Diffstat (limited to 'src/basic/util.c')
| -rw-r--r-- | src/basic/util.c | 273 |
1 files changed, 273 insertions, 0 deletions
diff --git a/src/basic/util.c b/src/basic/util.c new file mode 100644 index 0000000..f98ecf3 --- /dev/null +++ b/src/basic/util.c @@ -0,0 +1,273 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <errno.h> +#include <fcntl.h> +#include <sys/mman.h> + +#include "alloc-util.h" +#include "build.h" +#include "dirent-util.h" +#include "env-file.h" +#include "env-util.h" +#include "fd-util.h" +#include "fileio.h" +#include "hostname-util.h" +#include "log.h" +#include "macro.h" +#include "parse-util.h" +#include "stat-util.h" +#include "string-util.h" +#include "util.h" +#include "virt.h" + +int saved_argc = 0; +char **saved_argv = NULL; +static int saved_in_initrd = -1; + +bool kexec_loaded(void) { + _cleanup_free_ char *s = NULL; + + if (read_one_line_file("/sys/kernel/kexec_loaded", &s) < 0) + return false; + + return s[0] == '1'; +} + +int prot_from_flags(int flags) { + + switch (flags & O_ACCMODE) { + + case O_RDONLY: + return PROT_READ; + + case O_WRONLY: + return PROT_WRITE; + + case O_RDWR: + return PROT_READ|PROT_WRITE; + + default: + return -EINVAL; + } +} + +bool in_initrd(void) { + struct statfs s; + int r; + + if (saved_in_initrd >= 0) + return saved_in_initrd; + + /* We make two checks here: + * + * 1. the flag file /etc/initrd-release must exist + * 2. the root file system must be a memory file system + * + * The second check is extra paranoia, since misdetecting an + * initrd can have bad consequences due the initrd + * emptying when transititioning to the main systemd. + */ + + r = getenv_bool_secure("SYSTEMD_IN_INITRD"); + if (r < 0 && r != -ENXIO) + log_debug_errno(r, "Failed to parse $SYSTEMD_IN_INITRD, ignoring: %m"); + + if (r >= 0) + saved_in_initrd = r > 0; + else + saved_in_initrd = access("/etc/initrd-release", F_OK) >= 0 && + statfs("/", &s) >= 0 && + is_temporary_fs(&s); + + return saved_in_initrd; +} + +void in_initrd_force(bool value) { + saved_in_initrd = value; +} + +int on_ac_power(void) { + bool found_offline = false, found_online = false; + _cleanup_closedir_ DIR *d = NULL; + struct dirent *de; + + d = opendir("/sys/class/power_supply"); + if (!d) + return errno == ENOENT ? true : -errno; + + FOREACH_DIRENT(de, d, return -errno) { + _cleanup_close_ int fd = -1, device = -1; + char contents[6]; + ssize_t n; + + device = openat(dirfd(d), de->d_name, O_DIRECTORY|O_RDONLY|O_CLOEXEC|O_NOCTTY); + if (device < 0) { + if (IN_SET(errno, ENOENT, ENOTDIR)) + continue; + + return -errno; + } + + fd = openat(device, "type", O_RDONLY|O_CLOEXEC|O_NOCTTY); + if (fd < 0) { + if (errno == ENOENT) + continue; + + return -errno; + } + + n = read(fd, contents, sizeof(contents)); + if (n < 0) + return -errno; + + if (n != 6 || memcmp(contents, "Mains\n", 6)) + continue; + + safe_close(fd); + fd = openat(device, "online", O_RDONLY|O_CLOEXEC|O_NOCTTY); + if (fd < 0) { + if (errno == ENOENT) + continue; + + return -errno; + } + + n = read(fd, contents, sizeof(contents)); + if (n < 0) + return -errno; + + if (n != 2 || contents[1] != '\n') + return -EIO; + + if (contents[0] == '1') { + found_online = true; + break; + } else if (contents[0] == '0') + found_offline = true; + else + return -EIO; + } + + return found_online || !found_offline; +} + +int container_get_leader(const char *machine, pid_t *pid) { + _cleanup_free_ char *s = NULL, *class = NULL; + const char *p; + pid_t leader; + int r; + + assert(machine); + assert(pid); + + if (streq(machine, ".host")) { + *pid = 1; + return 0; + } + + if (!machine_name_is_valid(machine)) + return -EINVAL; + + p = strjoina("/run/systemd/machines/", machine); + r = parse_env_file(NULL, p, + "LEADER", &s, + "CLASS", &class); + if (r == -ENOENT) + return -EHOSTDOWN; + if (r < 0) + return r; + if (!s) + return -EIO; + + if (!streq_ptr(class, "container")) + return -EIO; + + r = parse_pid(s, &leader); + if (r < 0) + return r; + if (leader <= 1) + return -EIO; + + *pid = leader; + return 0; +} + +int version(void) { + puts("systemd " STRINGIFY(PROJECT_VERSION) " (" GIT_VERSION ")\n" + SYSTEMD_FEATURES); + return 0; +} + +/* This is a direct translation of str_verscmp from boot.c */ +static bool is_digit(int c) { + return c >= '0' && c <= '9'; +} + +static int c_order(int c) { + if (c == 0 || is_digit(c)) + return 0; + + if ((c >= 'a') && (c <= 'z')) + return c; + + return c + 0x10000; +} + +int str_verscmp(const char *s1, const char *s2) { + const char *os1, *os2; + + assert(s1); + assert(s2); + + os1 = s1; + os2 = s2; + + while (*s1 || *s2) { + int first; + + while ((*s1 && !is_digit(*s1)) || (*s2 && !is_digit(*s2))) { + int order; + + order = c_order(*s1) - c_order(*s2); + if (order != 0) + return order; + s1++; + s2++; + } + + while (*s1 == '0') + s1++; + while (*s2 == '0') + s2++; + + first = 0; + while (is_digit(*s1) && is_digit(*s2)) { + if (first == 0) + first = *s1 - *s2; + s1++; + s2++; + } + + if (is_digit(*s1)) + return 1; + if (is_digit(*s2)) + return -1; + + if (first != 0) + return first; + } + + return strcmp(os1, os2); +} + +/* Turn off core dumps but only if we're running outside of a container. */ +void disable_coredumps(void) { + int r; + + if (detect_container() > 0) + return; + + r = write_string_file("/proc/sys/kernel/core_pattern", "|/bin/false", WRITE_STRING_FILE_DISABLE_BUFFER); + if (r < 0) + log_debug_errno(r, "Failed to turn off coredumps, ignoring: %m"); +} |