src/memory_utils.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #ifndef __LXCFS_MEMORY_UTILS_H
   4 #define __LXCFS_MEMORY_UTILS_H
   5
   6 #include "config.h"
   7
   8 #include <dirent.h>
   9 #include <errno.h>
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <sys/types.h>
  14 #include <unistd.h>
  15
  16 #include "macro.h"
  17
  18 #define define_cleanup_function(type, cleaner)           \
  19         static inline void cleaner##_function(type *ptr) \
  20         {                                                \
  21                 if (*ptr)                                \
  22                         cleaner(*ptr);                   \
  23         }
  24
  25 #define call_cleaner(cleaner) __attribute__((__cleanup__(cleaner##_function)))
  26
  27 #define close_prot_errno_disarm(fd) \
  28         if (fd >= 0) {              \
  29                 int _e_ = errno;    \
  30                 close(fd);          \
  31                 errno = _e_;        \
  32                 fd = -EBADF;        \
  33         }
  34
  35 #define close_prot_errno_replace(fd, new_fd) \
  36         if (fd >= 0) {                       \
  37                 int _e_ = errno;             \
  38                 close(fd);                   \
  39                 errno = _e_;                 \
  40                 fd = new_fd;                 \
  41         }
  42
  43 static inline void close_prot_errno_disarm_function(int *fd)
  44 {
  45        close_prot_errno_disarm(*fd);
  46 }
  47 #define __do_close call_cleaner(close_prot_errno_disarm)
  48
  49 define_cleanup_function(FILE *, fclose);
  50 #define __do_fclose call_cleaner(fclose)
  51
  52 define_cleanup_function(DIR *, closedir);
  53 #define __do_closedir call_cleaner(closedir)
  54
  55 #define free_disarm(ptr)    \
  56         ({                  \
  57                 free(ptr);  \
  58                 ptr = NULL; \
  59         })
  60
  61 static inline void free_disarm_function(void *ptr)
  62 {
  63         free_disarm(*(void **)ptr);
  64 }
  65 #define __do_free call_cleaner(free_disarm)
  66
  67 static inline void free_string_list(char **list)
  68 {
  69         if (list) {
  70                 for (int i = 0; list[i]; i++)
  71                         free(list[i]);
  72                 free_disarm(list);
  73         }
  74 }
  75 define_cleanup_function(char **, free_string_list);
  76 #define __do_free_string_list call_cleaner(free_string_list)
  77
  78 static inline void *memdup(const void *data, size_t len)
  79 {
  80         void *copy = NULL;
  81
  82         copy = len ? malloc(len) : NULL;
  83         return copy ? memcpy(copy, data, len) : NULL;
  84 }
  85
  86 #define zalloc(__size__) (calloc(1, __size__))
  87
  88 #endif /* __LXCFS_MEMORY_UTILS_H */