git/git-compat-util.h
Dmitry Potapov adbc0b6b6e cygwin: Use native Win32 API for stat
lstat/stat functions in Cygwin are very slow, because they try to emulate
some *nix things that Git does not actually need. This patch adds Win32
specific implementation of these functions for Cygwin.

This implementation handles most situation directly but in some rare cases
it falls back on the implementation provided for Cygwin. This is necessary
for two reasons:

- Cygwin has its own file hierarchy, so absolute paths used in Cygwin is
  not suitable to be used Win32 API. cygwin_conv_to_win32_path can not be
  used because it automatically dereference Cygwin symbol links, also it
  causes extra syscall. Fortunately Git rarely use absolute paths, so we
  always use Cygwin implementation for absolute paths.

- Support of symbol links. Cygwin stores symbol links as ordinary using
  one of two possible formats. Therefore, the fast implementation falls
  back to Cygwin functions if it detects potential use of symbol links.

The speed of this implementation should be the same as mingw_lstat for
common cases, but it is considerable slower when the specified file name
does not exist.

Despite all efforts to make the fast implementation as robust as possible,
it may not work well for some very rare situations. I am aware only one
situation: use Cygwin mount to bind unrelated paths inside repository
together.  Therefore, the core.ignoreCygwinFSTricks configuration option is
provided, which controls whether native or Cygwin version of stat is used.

Signed-off-by: Dmitry Potapov <dpotapov@gmail.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2008-09-30 14:30:06 -07:00

386 lines
8.9 KiB
C

#ifndef GIT_COMPAT_UTIL_H
#define GIT_COMPAT_UTIL_H
#define _FILE_OFFSET_BITS 64
#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)
#if !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && !defined(_M_UNIX)
#define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
#define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
#endif
#define _ALL_SOURCE 1
#define _GNU_SOURCE 1
#define _BSD_SOURCE 1
#include <unistd.h>
#include <stdio.h>
#include <sys/stat.h>
#include <fcntl.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>
#ifndef __MINGW32__
#include <sys/wait.h>
#include <sys/poll.h>
#include <sys/socket.h>
#include <sys/ioctl.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 <inttypes.h>
#if defined(__CYGWIN__)
#undef _XOPEN_SOURCE
#include <grp.h>
#define _XOPEN_SOURCE 600
#include "compat/cygwin.h"
#else
#undef _ALL_SOURCE /* AIX 5.3L defines a struct list with _ALL_SOURCE. */
#include <grp.h>
#define _ALL_SOURCE 1
#endif
#else /* __MINGW32__ */
/* pull in Windows compatibility stuff */
#include "compat/mingw.h"
#endif /* __MINGW32__ */
#ifndef NO_ICONV
#include <iconv.h>
#endif
#ifndef NO_OPENSSL
#include <openssl/ssl.h>
#include <openssl/err.h>
#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 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)));
extern void set_die_routine(void (*routine)(const char *err, va_list params) NORETURN);
extern int prefixcmp(const char *str, const char *prefix);
extern time_t tm_to_time_t(const struct tm *tm);
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 NO_MMAP
#ifndef PROT_READ
#define PROT_READ 1
#define PROT_WRITE 2
#define MAP_PRIVATE 1
#define MAP_FAILED ((void*)-1)
#endif
#define mmap git_mmap
#define munmap git_munmap
extern void *git_mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
extern int git_munmap(void *start, size_t length);
/* This value must be multiple of (pagesize * 2) */
#define DEFAULT_PACKED_GIT_WINDOW_SIZE (1 * 1024 * 1024)
#else /* NO_MMAP */
#include <sys/mman.h>
/* This value must be multiple of (pagesize * 2) */
#define DEFAULT_PACKED_GIT_WINDOW_SIZE \
(sizeof(void*) >= 8 \
? 1 * 1024 * 1024 * 1024 \
: 32 * 1024 * 1024)
#endif /* NO_MMAP */
#ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
#define on_disk_bytes(st) ((st).st_size)
#else
#define on_disk_bytes(st) ((st).st_blocks * 512)
#endif
#define DEFAULT_PACKED_GIT_LIMIT \
((1024L * 1024L) * (sizeof(void*) >= 8 ? 8192 : 256))
#ifdef NO_PREAD
#define pread git_pread
extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
#endif
/*
* Forward decl that will remind us if its twin in cache.h changes.
* This function is used in compat/pread.c. But we can't include
* cache.h there.
*/
extern ssize_t read_in_full(int fd, void *buf, size_t count);
#ifdef NO_SETENV
#define setenv gitsetenv
extern int gitsetenv(const char *, const char *, int);
#endif
#ifdef NO_MKDTEMP
#define mkdtemp gitmkdtemp
extern char *gitmkdtemp(char *);
#endif
#ifdef NO_UNSETENV
#define unsetenv gitunsetenv
extern void gitunsetenv(const char *);
#endif
#ifdef NO_STRCASESTR
#define strcasestr gitstrcasestr
extern char *gitstrcasestr(const char *haystack, const char *needle);
#endif
#ifdef NO_STRLCPY
#define strlcpy gitstrlcpy
extern size_t gitstrlcpy(char *, const char *, size_t);
#endif
#ifdef NO_STRTOUMAX
#define strtoumax gitstrtoumax
extern uintmax_t gitstrtoumax(const char *, char **, int);
#endif
#ifdef NO_HSTRERROR
#define hstrerror githstrerror
extern 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 FREAD_READS_DIRECTORIES
#ifdef fopen
#undef fopen
#endif
#define fopen(a,b) git_fopen(a,b)
extern FILE *git_fopen(const char*, const char*);
#endif
#ifdef SNPRINTF_RETURNS_BOGUS
#define snprintf git_snprintf
extern int git_snprintf(char *str, size_t maxsize,
const char *format, ...);
#define vsnprintf git_vsnprintf
extern int git_vsnprintf(char *str, size_t maxsize,
const char *format, va_list ap);
#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
extern void release_pack_memory(size_t, int);
extern char *xstrdup(const char *str);
extern void *xmalloc(size_t size);
extern void *xmemdupz(const void *data, size_t len);
extern char *xstrndup(const char *str, size_t len);
extern void *xrealloc(void *ptr, size_t size);
extern void *xcalloc(size_t nmemb, size_t size);
extern void *xmmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
extern ssize_t xread(int fd, void *buf, size_t len);
extern ssize_t xwrite(int fd, const void *buf, size_t len);
extern int xdup(int fd);
extern FILE *xfdopen(int fd, const char *mode);
extern int xmkstemp(char *template);
static inline size_t xsize_t(off_t len)
{
return (size_t)len;
}
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 isspace
#undef isdigit
#undef isalpha
#undef isalnum
#undef tolower
#undef toupper
extern unsigned char sane_ctype[256];
#define GIT_SPACE 0x01
#define GIT_DIGIT 0x02
#define GIT_ALPHA 0x04
#define GIT_SPECIAL 0x08
#define sane_istest(x,mask) ((sane_ctype[(unsigned char)(x)] & (mask)) != 0)
#define isspace(x) sane_istest(x,GIT_SPACE)
#define isdigit(x) sane_istest(x,GIT_DIGIT)
#define isalpha(x) sane_istest(x,GIT_ALPHA)
#define isalnum(x) sane_istest(x,GIT_ALPHA | GIT_DIGIT)
#define isspecial(x) sane_istest(x,GIT_SPECIAL)
#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;
}
static inline int strtoul_ui(char const *s, int base, unsigned int *result)
{
unsigned long ul;
char *p;
errno = 0;
ul = strtoul(s, &p, base);
if (errno || *p || p == s || (unsigned int) ul != ul)
return -1;
*result = ul;
return 0;
}
static inline int strtol_i(char const *s, int base, int *result)
{
long ul;
char *p;
errno = 0;
ul = strtol(s, &p, base);
if (errno || *p || p == s || (int) ul != ul)
return -1;
*result = ul;
return 0;
}
#ifdef INTERNAL_QSORT
void git_qsort(void *base, size_t nmemb, size_t size,
int(*compar)(const void *, const void *));
#define qsort git_qsort
#endif
#ifndef DIR_HAS_BSD_GROUP_SEMANTICS
# define FORCE_DIR_SET_GID S_ISGID
#else
# define FORCE_DIR_SET_GID 0
#endif
#endif