git/compat/cygwin.c

143 строки
4.8 KiB
C

#define WIN32_LEAN_AND_MEAN
#include "../git-compat-util.h"
#include "win32.h"
#include "../cache.h" /* to read configuration */
static inline void filetime_to_timespec(const FILETIME *ft, struct timespec *ts)
{
long long winTime = ((long long)ft->dwHighDateTime << 32) +
ft->dwLowDateTime;
winTime -= 116444736000000000LL; /* Windows to Unix Epoch conversion */
/* convert 100-nsecond interval to seconds and nanoseconds */
ts->tv_sec = (time_t)(winTime/10000000);
ts->tv_nsec = (long)(winTime - ts->tv_sec*10000000LL) * 100;
}
#define size_to_blocks(s) (((s)+511)/512)
/* do_stat is a common implementation for cygwin_lstat and cygwin_stat.
*
* To simplify its logic, in the case of cygwin symlinks, this implementation
* falls back to the cygwin version of stat/lstat, which is provided as the
* last argument.
*/
static int do_stat(const char *file_name, struct stat *buf, stat_fn_t cygstat)
{
WIN32_FILE_ATTRIBUTE_DATA fdata;
if (file_name[0] == '/')
return cygstat (file_name, buf);
if (!(errno = get_file_attr(file_name, &fdata))) {
/*
* If the system attribute is set and it is not a directory then
* it could be a symbol link created in the nowinsymlinks mode.
* Normally, Cygwin works in the winsymlinks mode, so this situation
* is very unlikely. For the sake of simplicity of our code, let's
* Cygwin to handle it.
*/
if ((fdata.dwFileAttributes & FILE_ATTRIBUTE_SYSTEM) &&
!(fdata.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY))
return cygstat(file_name, buf);
/* fill out the stat structure */
buf->st_dev = buf->st_rdev = 0; /* not used by Git */
buf->st_ino = 0;
buf->st_mode = file_attr_to_st_mode(fdata.dwFileAttributes);
buf->st_nlink = 1;
buf->st_uid = buf->st_gid = 0;
#ifdef __CYGWIN_USE_BIG_TYPES__
buf->st_size = ((_off64_t)fdata.nFileSizeHigh << 32) +
fdata.nFileSizeLow;
#else
buf->st_size = (off_t)fdata.nFileSizeLow;
#endif
buf->st_blocks = size_to_blocks(buf->st_size);
filetime_to_timespec(&fdata.ftLastAccessTime, &buf->st_atim);
filetime_to_timespec(&fdata.ftLastWriteTime, &buf->st_mtim);
filetime_to_timespec(&fdata.ftCreationTime, &buf->st_ctim);
return 0;
} else if (errno == ENOENT) {
/*
* In the winsymlinks mode (which is the default), Cygwin
* emulates symbol links using Windows shortcut files. These
* files are formed by adding .lnk extension. So, if we have
* not found the specified file name, it could be that it is
* a symbol link. Let's Cygwin to deal with that.
*/
return cygstat(file_name, buf);
}
return -1;
}
/* We provide our own lstat/stat functions, since the provided Cygwin versions
* of these functions are too slow. These stat functions are tailored for Git's
* usage, and therefore they are not meant to be complete and correct emulation
* of lstat/stat functionality.
*/
static int cygwin_lstat(const char *path, struct stat *buf)
{
return do_stat(path, buf, lstat);
}
static int cygwin_stat(const char *path, struct stat *buf)
{
return do_stat(path, buf, stat);
}
/*
* At start up, we are trying to determine whether Win32 API or cygwin stat
* functions should be used. The choice is determined by core.ignorecygwinfstricks.
* Reading this option is not always possible immediately as git_dir may
* not be set yet. So until it is set, use cygwin lstat/stat functions.
* However, if core.filemode is set, we must use the Cygwin posix
* stat/lstat as the Windows stat functions do not determine posix filemode.
*
* Note that git_cygwin_config() does NOT call git_default_config() and this
* is deliberate. Many commands read from config to establish initial
* values in variables and later tweak them from elsewhere (e.g. command line).
* init_stat() is called lazily on demand, typically much late in the program,
* and calling git_default_config() from here would break such variables.
*/
static int native_stat = 1;
static int core_filemode = 1; /* matches trust_executable_bit default */
static int git_cygwin_config(const char *var, const char *value, void *cb)
{
if (!strcmp(var, "core.ignorecygwinfstricks"))
native_stat = git_config_bool(var, value);
else if (!strcmp(var, "core.filemode"))
core_filemode = git_config_bool(var, value);
return 0;
}
static int init_stat(void)
{
if (have_git_dir() && git_config(git_cygwin_config,NULL)) {
if (!core_filemode && native_stat) {
cygwin_stat_fn = cygwin_stat;
cygwin_lstat_fn = cygwin_lstat;
} else {
cygwin_stat_fn = stat;
cygwin_lstat_fn = lstat;
}
return 0;
}
return 1;
}
static int cygwin_stat_stub(const char *file_name, struct stat *buf)
{
return (init_stat() ? stat : *cygwin_stat_fn)(file_name, buf);
}
static int cygwin_lstat_stub(const char *file_name, struct stat *buf)
{
return (init_stat() ? lstat : *cygwin_lstat_fn)(file_name, buf);
}
stat_fn_t cygwin_stat_fn = cygwin_stat_stub;
stat_fn_t cygwin_lstat_fn = cygwin_lstat_stub;