git/compat/posix.h
Johannes Schindelin 7775181e07 mimalloc: offer a build-time option to enable it
By defining `USE_MIMALLOC`, Git can now be compiled with that
nicely-fast and small allocator.

Note that we have to disable a couple `DEVELOPER` options to build
mimalloc's source code, as it makes heavy use of declarations after
statements, among other things that disagree with Git's conventions.

We even have to silence some GCC warnings in non-DEVELOPER mode. For
example, the `-Wno-array-bounds` flag is needed because in `-O2` builds,
trying to call `NtCurrentTeb()` (which `_mi_thread_id()` does on
Windows) causes the bogus warning about a system header, likely related
to https://sourceforge.net/p/mingw-w64/mailman/message/37674519/ and to
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99578:

C:/git-sdk-64-minimal/mingw64/include/psdk_inc/intrin-impl.h:838:1:
        error: array subscript 0 is outside array bounds of 'long long unsigned int[0]' [-Werror=array-bounds]
  838 | __buildreadseg(__readgsqword, unsigned __int64, "gs", "q")
      | ^~~~~~~~~~~~~~

Also: The `mimalloc` library uses C11-style atomics, therefore we must
require that standard when compiling with GCC if we want to use
`mimalloc` (instead of requiring "only" C99). This is what we do in the
CMake definition already, therefore this commit does not need to touch
`contrib/buildsystems/`.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2025-08-07 19:15:34 +02:00

554 lines
12 KiB
C

#ifndef COMPAT_POSIX_H
#define COMPAT_POSIX_H
#define _FILE_OFFSET_BITS 64
/*
* Derived from Linux "Features Test Macro" header
* Convenience macros to test the versions of gcc (or
* a compatible compiler).
* Use them like this:
* #if GIT_GNUC_PREREQ (2,8)
* ... code requiring gcc 2.8 or later ...
* #endif
*
* This macro of course is not part of POSIX, but we need it for the UNUSED
* macro which is used by some of our POSIX compatibility wrappers.
*/
#if defined(__GNUC__) && defined(__GNUC_MINOR__)
# define GIT_GNUC_PREREQ(maj, min) \
((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
#else
#define GIT_GNUC_PREREQ(maj, min) 0
#endif
/*
* UNUSED marks a function parameter that is always unused. It also
* can be used to annotate a function, a variable, or a type that is
* always unused.
*
* A callback interface may dictate that a function accepts a
* parameter at that position, but the implementation of the function
* may not need to use the parameter. In such a case, mark the parameter
* with UNUSED.
*
* When a parameter may be used or unused, depending on conditional
* compilation, consider using MAYBE_UNUSED instead.
*/
#if GIT_GNUC_PREREQ(4, 5)
#define UNUSED __attribute__((unused)) \
__attribute__((deprecated ("parameter declared as UNUSED")))
#elif defined(__GNUC__)
#define UNUSED __attribute__((unused)) \
__attribute__((deprecated))
#else
#define UNUSED
#endif
#ifdef __MINGW64__
#define _POSIX_C_SOURCE 1
#elif defined(__sun__)
/*
* On Solaris, when _XOPEN_EXTENDED is set, its header file
* forces the programs to be XPG4v2, defeating any _XOPEN_SOURCE
* setting to say we are XPG5 or XPG6. Also on Solaris,
* XPG6 programs must be compiled with a c99 compiler, while
* non XPG6 programs must be compiled with a pre-c99 compiler.
*/
# if __STDC_VERSION__ - 0 >= 199901L
# define _XOPEN_SOURCE 600
# else
# define _XOPEN_SOURCE 500
# endif
#elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__NetBSD__) && \
!defined(__OpenBSD__) && !defined(__DragonFly__) && !defined(__MirBSD__) && \
!defined(__USLC__) && !defined(_M_UNIX) && !defined(__sgi) && \
!defined(__TANDEM) && !defined(__QNX__) && !defined(__CYGWIN__)
#define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500 */
#define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
#endif
#define _ALL_SOURCE 1
#define _GNU_SOURCE 1
#define _BSD_SOURCE 1
#ifndef _DEFAULT_SOURCE
#define _DEFAULT_SOURCE 1
#endif
#define _NETBSD_SOURCE 1
#define _SGI_SOURCE 1
#if defined(WIN32) && !defined(__CYGWIN__) /* Both MinGW and MSVC */
# if !defined(_WIN32_WINNT)
# define _WIN32_WINNT 0x0600
# endif
#define WIN32_LEAN_AND_MEAN /* stops windows.h including winsock.h */
#include <winsock2.h>
#ifndef NO_UNIX_SOCKETS
#include <afunix.h>
#endif
#include <windows.h>
#define GIT_WINDOWS_NATIVE
#endif
#include <unistd.h>
#include <stdio.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stddef.h>
#include <stdlib.h>
#include <stdarg.h>
#include <stdbool.h>
#include <string.h>
#ifdef HAVE_STRINGS_H
#include <strings.h> /* for strcasecmp() */
#endif
#include <errno.h>
#include <limits.h>
#include <locale.h>
#ifdef NEEDS_SYS_PARAM_H
#include <sys/param.h>
#endif
#include <sys/types.h>
#include <dirent.h>
#include <sys/time.h>
#include <time.h>
#include <signal.h>
#include <assert.h>
#include <regex.h>
#include <utime.h>
#include <syslog.h>
#if !defined(NO_POLL_H)
#include <poll.h>
#elif !defined(NO_SYS_POLL_H)
#include <sys/poll.h>
#else
/* Pull the compat stuff */
#include <poll.h>
#endif
#ifdef HAVE_BSD_SYSCTL
#include <sys/sysctl.h>
#endif
#if defined(__MINGW32__)
#include "mingw-posix.h"
#elif defined(_MSC_VER)
#include "msvc-posix.h"
#else
#include <sys/utsname.h>
#include <sys/wait.h>
#include <sys/resource.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/statvfs.h>
#include <termios.h>
#ifndef NO_SYS_SELECT_H
#include <sys/select.h>
#endif
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <pwd.h>
#include <sys/un.h>
#ifndef NO_INTTYPES_H
#include <inttypes.h>
#else
#include <stdint.h>
#endif
#ifdef HAVE_ARC4RANDOM_LIBBSD
#include <bsd/stdlib.h>
#endif
#ifdef HAVE_GETRANDOM
#include <sys/random.h>
#endif
#ifdef NO_INTPTR_T
/*
* On I16LP32, ILP32 and LP64 "long" is the safe bet, however
* on LLP86, IL33LLP64 and P64 it needs to be "long long",
* while on IP16 and IP16L32 it is "int" (resp. "short")
* Size needs to match (or exceed) 'sizeof(void *)'.
* We can't take "long long" here as not everybody has it.
*/
typedef long intptr_t;
typedef unsigned long uintptr_t;
#endif
#undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
#include <grp.h>
#define _ALL_SOURCE 1
#endif
#ifdef USE_MIMALLOC
#include "mimalloc.h"
#define malloc mi_malloc
#define calloc mi_calloc
#define realloc mi_realloc
#define free mi_free
#define strdup mi_strdup
#define strndup mi_strndup
#endif
#ifdef MKDIR_WO_TRAILING_SLASH
#define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
int compat_mkdir_wo_trailing_slash(const char*, mode_t);
#endif
#ifdef time
#undef time
#endif
static inline time_t git_time(time_t *tloc)
{
struct timeval tv;
/*
* Avoid time(NULL), which can disagree with gettimeofday(2)
* and filesystem timestamps.
*/
gettimeofday(&tv, NULL);
if (tloc)
*tloc = tv.tv_sec;
return tv.tv_sec;
}
#define time git_time
#ifdef NO_STRUCT_ITIMERVAL
struct itimerval {
struct timeval it_interval;
struct timeval it_value;
};
#endif
#ifdef NO_SETITIMER
static inline int git_setitimer(int which UNUSED,
const struct itimerval *value UNUSED,
struct itimerval *newvalue UNUSED) {
return 0; /* pretend success */
}
#undef setitimer
#define setitimer(which,value,ovalue) git_setitimer(which,value,ovalue)
#endif
#ifndef NO_LIBGEN_H
#include <libgen.h>
#else
#define basename gitbasename
char *gitbasename(char *);
#define dirname gitdirname
char *gitdirname(char *);
#endif
#ifndef NO_ICONV
#include <iconv.h>
#endif
/* On most systems <netdb.h> would have given us this, but
* not on some systems (e.g. z/OS).
*/
#ifndef NI_MAXHOST
#define NI_MAXHOST 1025
#endif
#ifndef NI_MAXSERV
#define NI_MAXSERV 32
#endif
/* 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 NAME_MAX
#define NAME_MAX 255
#endif
typedef uintmax_t timestamp_t;
#define PRItime PRIuMAX
#define parse_timestamp strtoumax
#define TIME_MAX UINTMAX_MAX
#define TIME_MIN 0
int lstat_cache_aware_rmdir(const char *path);
#if !defined(__MINGW32__) && !defined(_MSC_VER)
#define rmdir lstat_cache_aware_rmdir
#endif
#if defined(NO_MMAP) || defined(USE_WIN32_MMAP)
#ifndef PROT_READ
#define PROT_READ 1
#define PROT_WRITE 2
#define MAP_PRIVATE 1
#endif
#define mmap git_mmap
#define munmap git_munmap
void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
int git_munmap(void *start, size_t length);
#else /* NO_MMAP || USE_WIN32_MMAP */
#include <sys/mman.h>
#endif /* NO_MMAP || USE_WIN32_MMAP */
#ifndef MAP_FAILED
#define MAP_FAILED ((void *)-1)
#endif
#ifdef NEEDS_MODE_TRANSLATION
#undef S_IFMT
#undef S_IFREG
#undef S_IFDIR
#undef S_IFLNK
#undef S_IFBLK
#undef S_IFCHR
#undef S_IFIFO
#undef S_IFSOCK
#define S_IFMT 0170000
#define S_IFREG 0100000
#define S_IFDIR 0040000
#define S_IFLNK 0120000
#define S_IFBLK 0060000
#define S_IFCHR 0020000
#define S_IFIFO 0010000
#define S_IFSOCK 0140000
#ifdef stat
#undef stat
#endif
#define stat(path, buf) git_stat(path, buf)
int git_stat(const char *, struct stat *);
#ifdef fstat
#undef fstat
#endif
#define fstat(fd, buf) git_fstat(fd, buf)
int git_fstat(int, struct stat *);
#ifdef lstat
#undef lstat
#endif
#define lstat(path, buf) git_lstat(path, buf)
int git_lstat(const char *, struct stat *);
#endif
#ifdef NO_PREAD
#define pread git_pread
ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
#endif
#ifdef NO_SETENV
#define setenv gitsetenv
int gitsetenv(const char *, const char *, int);
#endif
#ifdef NO_MKDTEMP
#define mkdtemp gitmkdtemp
char *gitmkdtemp(char *);
#endif
#ifdef NO_UNSETENV
#define unsetenv gitunsetenv
int gitunsetenv(const char *);
#endif
#ifdef NO_STRCASESTR
#define strcasestr gitstrcasestr
char *gitstrcasestr(const char *haystack, const char *needle);
#endif
#ifdef NO_STRLCPY
#define strlcpy gitstrlcpy
size_t gitstrlcpy(char *, const char *, size_t);
#endif
#ifdef NO_STRTOUMAX
#define strtoumax gitstrtoumax
uintmax_t gitstrtoumax(const char *, char **, int);
#define strtoimax gitstrtoimax
intmax_t gitstrtoimax(const char *, char **, int);
#endif
#ifdef NO_HSTRERROR
#define hstrerror githstrerror
const char *githstrerror(int herror);
#endif
#ifdef NO_MEMMEM
#define memmem gitmemmem
void *gitmemmem(const void *haystack, size_t haystacklen,
const void *needle, size_t needlelen);
#endif
#ifdef OVERRIDE_STRDUP
#ifdef strdup
#undef strdup
#endif
#define strdup gitstrdup
char *gitstrdup(const char *s);
#endif
#ifdef NO_GETPAGESIZE
#define getpagesize() sysconf(_SC_PAGESIZE)
#endif
#ifndef O_CLOEXEC
#define O_CLOEXEC 0
#endif
#ifdef FREAD_READS_DIRECTORIES
# if !defined(SUPPRESS_FOPEN_REDEFINITION)
# ifdef fopen
# undef fopen
# endif
# define fopen(a,b) git_fopen(a,b)
# endif
FILE *git_fopen(const char*, const char*);
#endif
#ifdef SNPRINTF_RETURNS_BOGUS
#ifdef snprintf
#undef snprintf
#endif
#define snprintf git_snprintf
int git_snprintf(char *str, size_t maxsize,
const char *format, ...);
#ifdef vsnprintf
#undef vsnprintf
#endif
#define vsnprintf git_vsnprintf
int git_vsnprintf(char *str, size_t maxsize,
const char *format, va_list ap);
#endif
#ifdef OPEN_RETURNS_EINTR
#undef open
#define open git_open_with_retry
int git_open_with_retry(const char *path, int flag, ...);
#endif
#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
#ifdef NO_INET_PTON
int inet_pton(int af, const char *src, void *dst);
#endif
#ifdef NO_INET_NTOP
const char *inet_ntop(int af, const void *src, char *dst, size_t size);
#endif
#ifdef NO_PTHREADS
#define atexit git_atexit
int git_atexit(void (*handler)(void));
#endif
#ifndef HOST_NAME_MAX
#define HOST_NAME_MAX 256
#endif
#include "../sane-ctype.h"
void git_stable_qsort(void *base, size_t nmemb, size_t size,
int(*compar)(const void *, const void *));
#ifdef INTERNAL_QSORT
#define qsort git_stable_qsort
#endif
#define QSORT(base, n, compar) sane_qsort((base), (n), sizeof(*(base)), compar)
static inline void sane_qsort(void *base, size_t nmemb, size_t size,
int(*compar)(const void *, const void *))
{
if (nmemb > 1)
qsort(base, nmemb, size, compar);
}
#define STABLE_QSORT(base, n, compar) \
git_stable_qsort((base), (n), sizeof(*(base)), compar)
#ifndef HAVE_ISO_QSORT_S
int git_qsort_s(void *base, size_t nmemb, size_t size,
int (*compar)(const void *, const void *, void *), void *ctx);
#define qsort_s git_qsort_s
#endif
#define QSORT_S(base, n, compar, ctx) do { \
if (qsort_s((base), (n), sizeof(*(base)), compar, ctx)) \
BUG("qsort_s() failed"); \
} while (0)
#ifdef NO_NSEC
#undef USE_NSEC
#define ST_CTIME_NSEC(st) 0
#define ST_MTIME_NSEC(st) 0
#else
#ifdef USE_ST_TIMESPEC
#define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctimespec.tv_nsec))
#define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtimespec.tv_nsec))
#else
#define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
#define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
#endif
#endif
#ifndef va_copy
/*
* Since an obvious implementation of va_list would be to make it a
* pointer into the stack frame, a simple assignment will work on
* many systems. But let's try to be more portable.
*/
#ifdef __va_copy
#define va_copy(dst, src) __va_copy(dst, src)
#else
#define va_copy(dst, src) ((dst) = (src))
#endif
#endif
#ifndef _POSIX_THREAD_SAFE_FUNCTIONS
static inline void git_flockfile(FILE *fh UNUSED)
{
; /* nothing */
}
static inline void git_funlockfile(FILE *fh UNUSED)
{
; /* nothing */
}
#undef flockfile
#undef funlockfile
#undef getc_unlocked
#define flockfile(fh) git_flockfile(fh)
#define funlockfile(fh) git_funlockfile(fh)
#define getc_unlocked(fh) getc(fh)
#endif
#ifdef FILENO_IS_A_MACRO
int git_fileno(FILE *stream);
# ifndef COMPAT_CODE_FILENO
# undef fileno
# define fileno(p) git_fileno(p)
# endif
#endif
#ifdef NEED_ACCESS_ROOT_HANDLER
int git_access(const char *path, int mode);
# ifndef COMPAT_CODE_ACCESS
# ifdef access
# undef access
# endif
# define access(path, mode) git_access(path, mode)
# endif
#endif
#endif /* COMPAT_POSIX_H */