text: #ifndef GIT_COMPAT_UTIL_H
  #define GIT_COMPAT_UTIL_H
  
  #ifndef FLEX_ARRAY
  /*
   * See if our compiler is known to support flexible array members.
   */
  #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)
  # define FLEX_ARRAY /* empty */
  #elif defined(__GNUC__)
  # if (__GNUC__ >= 3)
  #  define FLEX_ARRAY /* empty */
  # else
  #  define FLEX_ARRAY 0 /* older GNU extension */
  # endif
  #endif
  
  /*
   * Otherwise, default to safer but a bit wasteful traditional style
   */
  #ifndef FLEX_ARRAY
  # define FLEX_ARRAY 1
  #endif
  #endif
  
  #define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
  
  #ifdef __GNUC__
  #define TYPEOF(x) (__typeof__(x))
  #else
  #define TYPEOF(x)
  #endif
  
  #define MSB(x, bits) ((x) & TYPEOF(x)(~0ULL << (sizeof(x) * 8 - (bits))))
  #define HAS_MULTI_BITS(i)  ((i) & ((i) - 1))  /* checks if an integer has more than 1 bit set */
  
  /* Approximation of the length of the decimal representation of this type. */
  #define decimal_length(x)	((int)(sizeof(x) * 2.56 + 0.5) + 1)
  
  #define _ALL_SOURCE 1
  #define _BSD_SOURCE 1
  #define HAS_BOOL
  
  #include <unistd.h>
  #include <stdio.h>
  #include <sys/stat.h>
  #include <sys/statfs.h>
  #include <fcntl.h>
  #include <stdbool.h>
  #include <stddef.h>
  #include <stdlib.h>
  #include <stdarg.h>
  #include <string.h>
  #include <errno.h>
  #include <limits.h>
  #include <sys/param.h>
  #include <sys/types.h>
  #include <dirent.h>
  #include <sys/time.h>
  #include <time.h>
  #include <signal.h>
  #include <fnmatch.h>
  #include <assert.h>
  #include <regex.h>
  #include <utime.h>
  #include <sys/wait.h>
  #include <sys/poll.h>
  #include <sys/socket.h>
  #include <sys/ioctl.h>
  #include <inttypes.h>
  #include <linux/magic.h>
  #include "types.h"
  #include <sys/ttydefaults.h>
  #include <lk/debugfs.h>
  #include <termios.h>
  
  extern const char *graph_line;
  extern const char *graph_dotted_line;
  extern char buildid_dir[];
  extern char tracing_events_path[];
  extern void perf_debugfs_set_path(const char *mountpoint);
  const char *perf_debugfs_mount(const char *mountpoint);
  
  /* On most systems <limits.h> would have given us this, but
   * not on some systems (e.g. GNU/Hurd).
   */
  #ifndef PATH_MAX
  #define PATH_MAX 4096
  #endif
  
  #ifndef PRIuMAX
  #define PRIuMAX "llu"
  #endif
  
  #ifndef PRIu32
  #define PRIu32 "u"
  #endif
  
  #ifndef PRIx32
  #define PRIx32 "x"
  #endif
  
  #ifndef PATH_SEP
  #define PATH_SEP ':'
  #endif
  
  #ifndef STRIP_EXTENSION
  #define STRIP_EXTENSION ""
  #endif
  
  #ifndef has_dos_drive_prefix
  #define has_dos_drive_prefix(path) 0
  #endif
  
  #ifndef is_dir_sep
  #define is_dir_sep(c) ((c) == '/')
  #endif
  
  #ifdef __GNUC__
  #define NORETURN __attribute__((__noreturn__))
  #else
  #define NORETURN
  #ifndef __attribute__
  #define __attribute__(x)
  #endif
  #endif
  
  /* General helper functions */
  extern void usage(const char *err) NORETURN;
  extern void die(const char *err, ...) NORETURN __attribute__((format (printf, 1, 2)));
  extern int error(const char *err, ...) __attribute__((format (printf, 1, 2)));
  extern void warning(const char *err, ...) __attribute__((format (printf, 1, 2)));
  
  #include "../../../include/linux/stringify.h"
  
  #define DIE_IF(cnd)	\
  	do { if (cnd)	\
  		die(" at (" __FILE__ ":" __stringify(__LINE__) "): "	\
  		    __stringify(cnd) "\n");				\
  	} while (0)
  
  
  extern void set_die_routine(void (*routine)(const char *err, va_list params) NORETURN);
  
  extern int prefixcmp(const char *str, const char *prefix);
  extern void set_buildid_dir(void);
  extern void disable_buildid_cache(void);
  
  static inline const char *skip_prefix(const char *str, const char *prefix)
  {
  	size_t len = strlen(prefix);
  	return strncmp(str, prefix, len) ? NULL : str + len;
  }
  
  #ifdef __GLIBC_PREREQ
  #if __GLIBC_PREREQ(2, 1)
  #define HAVE_STRCHRNUL
  #endif
  #endif
  
  #ifndef HAVE_STRCHRNUL
  #define strchrnul gitstrchrnul
  static inline char *gitstrchrnul(const char *s, int c)
  {
  	while (*s && *s != c)
  		s++;
  	return (char *)s;
  }
  #endif
  
  /*
   * Wrappers:
   */
  extern char *xstrdup(const char *str);
  extern void *xrealloc(void *ptr, size_t size) __attribute__((weak));
  
  
  static inline void *zalloc(size_t size)
  {
  	return calloc(1, size);
  }
  
  static inline int has_extension(const char *filename, const char *ext)
  {
  	size_t len = strlen(filename);
  	size_t extlen = strlen(ext);
  
  	return len > extlen && !memcmp(filename + len - extlen, ext, extlen);
  }
  
  /* Sane ctype - no locale, and works with signed chars */
  #undef isascii
  #undef isspace
  #undef isdigit
  #undef isxdigit
  #undef isalpha
  #undef isprint
  #undef isalnum
  #undef islower
  #undef isupper
  #undef tolower
  #undef toupper
  
  #ifndef NSEC_PER_MSEC
  #define NSEC_PER_MSEC	1000000L
  #endif
  
  extern unsigned char sane_ctype[256];
  #define GIT_SPACE		0x01
  #define GIT_DIGIT		0x02
  #define GIT_ALPHA		0x04
  #define GIT_GLOB_SPECIAL	0x08
  #define GIT_REGEX_SPECIAL	0x10
  #define GIT_PRINT_EXTRA		0x20
  #define GIT_PRINT		0x3E
  #define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
  #define isascii(x) (((x) & ~0x7f) == 0)
  #define isspace(x) sane_istest(x,GIT_SPACE)
  #define isdigit(x) sane_istest(x,GIT_DIGIT)
  #define isxdigit(x)	\
  	(sane_istest(toupper(x), GIT_ALPHA | GIT_DIGIT) && toupper(x) < 'G')
  #define isalpha(x) sane_istest(x,GIT_ALPHA)
  #define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
  #define isprint(x) sane_istest(x,GIT_PRINT)
  #define islower(x) (sane_istest(x,GIT_ALPHA) && (x & 0x20))
  #define isupper(x) (sane_istest(x,GIT_ALPHA) && !(x & 0x20))
  #define tolower(x) sane_case((unsigned char)(x), 0x20)
  #define toupper(x) sane_case((unsigned char)(x), 0)
  
  static inline int sane_case(int x, int high)
  {
  	if (sane_istest(x, GIT_ALPHA))
  		x = (x & ~0x20) | high;
  	return x;
  }
  
  int mkdir_p(char *path, mode_t mode);
  int copyfile(const char *from, const char *to);
  
  s64 perf_atoll(const char *str);
  char **argv_split(const char *str, int *argcp);
  void argv_free(char **argv);
  bool strglobmatch(const char *str, const char *pat);
  bool strlazymatch(const char *str, const char *pat);
  int strtailcmp(const char *s1, const char *s2);
  char *strxfrchar(char *s, char from, char to);
  unsigned long convert_unit(unsigned long value, char *unit);
  int readn(int fd, void *buf, size_t size);
  
  struct perf_event_attr;
  
  void event_attr_init(struct perf_event_attr *attr);
  
  #define _STR(x) #x
  #define STR(x) _STR(x)
  
  /*
   *  Determine whether some value is a power of two, where zero is
   * *not* considered a power of two.
   */
  
  static inline __attribute__((const))
  bool is_power_of_2(unsigned long n)
  {
  	return (n != 0 && ((n & (n - 1)) == 0));
  }
  
  size_t hex_width(u64 v);
  int hex2u64(const char *ptr, u64 *val);
  
  char *ltrim(char *s);
  char *rtrim(char *s);
  
  void dump_stack(void);
  
  extern unsigned int page_size;
  
  void get_term_dimensions(struct winsize *ws);
  #endif /* GIT_COMPAT_UTIL_H */
  