src/basic/util.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 #include <alloca.h>
   5 #include <errno.h>
   6 #include <fcntl.h>
   7 #include <inttypes.h>
   8 #include <limits.h>
   9 #include <locale.h>
  10 #include <stdarg.h>
  11 #include <stdbool.h>
  12 #include <stddef.h>
  13 #include <stdint.h>
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <string.h>
  17 #include <sys/inotify.h>
  18 #include <sys/socket.h>
  19 #include <sys/stat.h>
  20 #include <sys/statfs.h>
  21 #include <sys/sysmacros.h>
  22 #include <sys/types.h>
  23 #include <time.h>
  24 #include <unistd.h>
  25
  26 #include "format-util.h"
  27 #include "macro.h"
  28 #include "missing.h"
  29 #include "time-util.h"
  30
  31 size_t page_size(void) _pure_;
  32 #define PAGE_ALIGN(l) ALIGN_TO((l), page_size())
  33
  34 static inline const char* yes_no(bool b) {
  35         return b ? "yes" : "no";
  36 }
  37
  38 static inline const char* true_false(bool b) {
  39         return b ? "true" : "false";
  40 }
  41
  42 static inline const char* one_zero(bool b) {
  43         return b ? "1" : "0";
  44 }
  45
  46 static inline const char* enable_disable(bool b) {
  47         return b ? "enable" : "disable";
  48 }
  49
  50 bool plymouth_running(void);
  51
  52 bool display_is_local(const char *display) _pure_;
  53
  54 #define NULSTR_FOREACH(i, l)                                    \
  55         for ((i) = (l); (i) && *(i); (i) = strchr((i), 0)+1)
  56
  57 #define NULSTR_FOREACH_PAIR(i, j, l)                             \
  58         for ((i) = (l), (j) = strchr((i), 0)+1; (i) && *(i); (i) = strchr((j), 0)+1, (j) = *(i) ? strchr((i), 0)+1 : (i))
  59
  60 extern int saved_argc;
  61 extern char **saved_argv;
  62
  63 bool kexec_loaded(void);
  64
  65 int prot_from_flags(int flags) _const_;
  66
  67 bool in_initrd(void);
  68 void in_initrd_force(bool value);
  69
  70 void *xbsearch_r(const void *key, const void *base, size_t nmemb, size_t size,
  71                  int (*compar) (const void *, const void *, void *),
  72                  void *arg);
  73
  74 /**
  75  * Normal bsearch requires base to be nonnull. Here were require
  76  * that only if nmemb > 0.
  77  */
  78 static inline void* bsearch_safe(const void *key, const void *base,
  79                                  size_t nmemb, size_t size, comparison_fn_t compar) {
  80         if (nmemb <= 0)
  81                 return NULL;
  82
  83         assert(base);
  84         return bsearch(key, base, nmemb, size, compar);
  85 }
  86
  87 /**
  88  * Normal qsort requires base to be nonnull. Here were require
  89  * that only if nmemb > 0.
  90  */
  91 static inline void qsort_safe(void *base, size_t nmemb, size_t size, comparison_fn_t compar) {
  92         if (nmemb <= 1)
  93                 return;
  94
  95         assert(base);
  96         qsort(base, nmemb, size, compar);
  97 }
  98
  99 /* A wrapper around the above, but that adds typesafety: the element size is automatically derived from the type and so
 100  * is the prototype for the comparison function */
 101 #define typesafe_qsort(p, n, func)                                      \
 102         ({                                                              \
 103                 int (*_func_)(const typeof(p[0])*, const typeof(p[0])*) = func; \
 104                 qsort_safe((p), (n), sizeof((p)[0]), (__compar_fn_t) _func_); \
 105         })
 106
 107 static inline void qsort_r_safe(void *base, size_t nmemb, size_t size, int (*compar)(const void*, const void*, void*), void *userdata) {
 108         if (nmemb <= 1)
 109                 return;
 110
 111         assert(base);
 112         qsort_r(base, nmemb, size, compar, userdata);
 113 }
 114
 115 /**
 116  * Normal memcpy requires src to be nonnull. We do nothing if n is 0.
 117  */
 118 static inline void memcpy_safe(void *dst, const void *src, size_t n) {
 119         if (n == 0)
 120                 return;
 121         assert(src);
 122         memcpy(dst, src, n);
 123 }
 124
 125 int on_ac_power(void);
 126
 127 #define memzero(x,l) (memset((x), 0, (l)))
 128 #define zero(x) (memzero(&(x), sizeof(x)))
 129
 130 static inline void *mempset(void *s, int c, size_t n) {
 131         memset(s, c, n);
 132         return (uint8_t*)s + n;
 133 }
 134
 135 static inline void _reset_errno_(int *saved_errno) {
 136         errno = *saved_errno;
 137 }
 138
 139 #define PROTECT_ERRNO _cleanup_(_reset_errno_) __attribute__((unused)) int _saved_errno_ = errno
 140
 141 static inline int negative_errno(void) {
 142         /* This helper should be used to shut up gcc if you know 'errno' is
 143          * negative. Instead of "return -errno;", use "return negative_errno();"
 144          * It will suppress bogus gcc warnings in case it assumes 'errno' might
 145          * be 0 and thus the caller's error-handling might not be triggered. */
 146         assert_return(errno > 0, -EINVAL);
 147         return -errno;
 148 }
 149
 150 static inline unsigned u64log2(uint64_t n) {
 151 #if __SIZEOF_LONG_LONG__ == 8
 152         return (n > 1) ? (unsigned) __builtin_clzll(n) ^ 63U : 0;
 153 #else
 154 #error "Wut?"
 155 #endif
 156 }
 157
 158 static inline unsigned u32ctz(uint32_t n) {
 159 #if __SIZEOF_INT__ == 4
 160         return __builtin_ctz(n);
 161 #else
 162 #error "Wut?"
 163 #endif
 164 }
 165
 166 static inline unsigned log2i(int x) {
 167         assert(x > 0);
 168
 169         return __SIZEOF_INT__ * 8 - __builtin_clz(x) - 1;
 170 }
 171
 172 static inline unsigned log2u(unsigned x) {
 173         assert(x > 0);
 174
 175         return sizeof(unsigned) * 8 - __builtin_clz(x) - 1;
 176 }
 177
 178 static inline unsigned log2u_round_up(unsigned x) {
 179         assert(x > 0);
 180
 181         if (x == 1)
 182                 return 0;
 183
 184         return log2u(x - 1) + 1;
 185 }
 186
 187 int container_get_leader(const char *machine, pid_t *pid);
 188
 189 int namespace_open(pid_t pid, int *pidns_fd, int *mntns_fd, int *netns_fd, int *userns_fd, int *root_fd);
 190 int namespace_enter(int pidns_fd, int mntns_fd, int netns_fd, int userns_fd, int root_fd);
 191
 192 uint64_t physical_memory(void);
 193 uint64_t physical_memory_scale(uint64_t v, uint64_t max);
 194
 195 uint64_t system_tasks_max(void);
 196 uint64_t system_tasks_max_scale(uint64_t v, uint64_t max);
 197
 198 int version(void);
 199
 200 int str_verscmp(const char *s1, const char *s2);
 201
 202 void disable_coredumps(void);