src/basic/util.h

   1 #pragma once
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <alloca.h>
  23 #include <errno.h>
  24 #include <fcntl.h>
  25 #include <inttypes.h>
  26 #include <limits.h>
  27 #include <locale.h>
  28 #include <stdarg.h>
  29 #include <stdbool.h>
  30 #include <stddef.h>
  31 #include <stdint.h>
  32 #include <stdio.h>
  33 #include <stdlib.h>
  34 #include <string.h>
  35 #include <sys/inotify.h>
  36 #include <sys/socket.h>
  37 #include <sys/stat.h>
  38 #include <sys/statfs.h>
  39 #include <sys/sysmacros.h>
  40 #include <sys/types.h>
  41 #include <time.h>
  42 #include <unistd.h>
  43
  44 #include "formats-util.h"
  45 #include "macro.h"
  46 #include "missing.h"
  47 #include "time-util.h"
  48
  49 size_t page_size(void) _pure_;
  50 #define PAGE_ALIGN(l) ALIGN_TO((l), page_size())
  51
  52 static inline const char* yes_no(bool b) {
  53         return b ? "yes" : "no";
  54 }
  55
  56 static inline const char* true_false(bool b) {
  57         return b ? "true" : "false";
  58 }
  59
  60 static inline const char* one_zero(bool b) {
  61         return b ? "1" : "0";
  62 }
  63
  64 void execute_directories(const char* const* directories, usec_t timeout, char *argv[]);
  65
  66 bool plymouth_running(void);
  67
  68 bool display_is_local(const char *display) _pure_;
  69 int socket_from_display(const char *display, char **path);
  70
  71 int block_get_whole_disk(dev_t d, dev_t *ret);
  72
  73 #define NULSTR_FOREACH(i, l)                                    \
  74         for ((i) = (l); (i) && *(i); (i) = strchr((i), 0)+1)
  75
  76 #define NULSTR_FOREACH_PAIR(i, j, l)                             \
  77         for ((i) = (l), (j) = strchr((i), 0)+1; (i) && *(i); (i) = strchr((j), 0)+1, (j) = *(i) ? strchr((i), 0)+1 : (i))
  78
  79 extern int saved_argc;
  80 extern char **saved_argv;
  81
  82 bool kexec_loaded(void);
  83
  84 int prot_from_flags(int flags) _const_;
  85
  86 int fork_agent(pid_t *pid, const int except[], unsigned n_except, const char *path, ...);
  87
  88 bool in_initrd(void);
  89 void in_initrd_force(bool value);
  90
  91 void *xbsearch_r(const void *key, const void *base, size_t nmemb, size_t size,
  92                  int (*compar) (const void *, const void *, void *),
  93                  void *arg);
  94
  95 /**
  96  * Normal qsort requires base to be nonnull. Here were require
  97  * that only if nmemb > 0.
  98  */
  99 static inline void qsort_safe(void *base, size_t nmemb, size_t size, comparison_fn_t compar) {
 100         if (nmemb <= 1)
 101                 return;
 102
 103         assert(base);
 104         qsort(base, nmemb, size, compar);
 105 }
 106
 107 /**
 108  * Normal memcpy requires src to be nonnull. We do nothing if n is 0.
 109  */
 110 static inline void memcpy_safe(void *dst, const void *src, size_t n) {
 111         if (n == 0)
 112                 return;
 113         assert(src);
 114         memcpy(dst, src, n);
 115 }
 116
 117 int on_ac_power(void);
 118
 119 #define memzero(x,l) (memset((x), 0, (l)))
 120 #define zero(x) (memzero(&(x), sizeof(x)))
 121
 122 static inline void *mempset(void *s, int c, size_t n) {
 123         memset(s, c, n);
 124         return (uint8_t*)s + n;
 125 }
 126
 127 static inline void _reset_errno_(int *saved_errno) {
 128         errno = *saved_errno;
 129 }
 130
 131 #define PROTECT_ERRNO _cleanup_(_reset_errno_) __attribute__((unused)) int _saved_errno_ = errno
 132
 133 static inline int negative_errno(void) {
 134         /* This helper should be used to shut up gcc if you know 'errno' is
 135          * negative. Instead of "return -errno;", use "return negative_errno();"
 136          * It will suppress bogus gcc warnings in case it assumes 'errno' might
 137          * be 0 and thus the caller's error-handling might not be triggered. */
 138         assert_return(errno > 0, -EINVAL);
 139         return -errno;
 140 }
 141
 142 static inline unsigned u64log2(uint64_t n) {
 143 #if __SIZEOF_LONG_LONG__ == 8
 144         return (n > 1) ? (unsigned) __builtin_clzll(n) ^ 63U : 0;
 145 #else
 146 #error "Wut?"
 147 #endif
 148 }
 149
 150 static inline unsigned u32ctz(uint32_t n) {
 151 #if __SIZEOF_INT__ == 4
 152         return __builtin_ctz(n);
 153 #else
 154 #error "Wut?"
 155 #endif
 156 }
 157
 158 static inline unsigned log2i(int x) {
 159         assert(x > 0);
 160
 161         return __SIZEOF_INT__ * 8 - __builtin_clz(x) - 1;
 162 }
 163
 164 static inline unsigned log2u(unsigned x) {
 165         assert(x > 0);
 166
 167         return sizeof(unsigned) * 8 - __builtin_clz(x) - 1;
 168 }
 169
 170 static inline unsigned log2u_round_up(unsigned x) {
 171         assert(x > 0);
 172
 173         if (x == 1)
 174                 return 0;
 175
 176         return log2u(x - 1) + 1;
 177 }
 178
 179 bool id128_is_valid(const char *s) _pure_;
 180
 181 int container_get_leader(const char *machine, pid_t *pid);
 182
 183 int namespace_open(pid_t pid, int *pidns_fd, int *mntns_fd, int *netns_fd, int *userns_fd, int *root_fd);
 184 int namespace_enter(int pidns_fd, int mntns_fd, int netns_fd, int userns_fd, int root_fd);
 185
 186 uint64_t physical_memory(void);
 187 uint64_t physical_memory_scale(uint64_t v, uint64_t max);
 188
 189 int update_reboot_parameter_and_warn(const char *param);
 190
 191 int version(void);