diff options
Diffstat (limited to 'compat/cygwin.c')
| -rw-r--r-- | compat/cygwin.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/compat/cygwin.c b/compat/cygwin.c new file mode 100644 index 0000000000..dfe9b3084f --- /dev/null +++ b/compat/cygwin.c @@ -0,0 +1,142 @@ +#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; + |