From 61ad94d0b8ec5d83c11511e33de8cc8761339cb8 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Fri, 7 Dec 2018 13:39:30 +0100 Subject: [PATCH 1/2] clean: do not traverse mount points It seems to be not exactly rare on Windows to install NTFS junction points (the equivalent of "bind mounts" on Linux/Unix) in worktrees, e.g. to map some development tools into a subdirectory. In such a scenario, it is pretty horrible if `git clean -dfx` traverses into the mapped directory and starts to "clean up". Let's just not do that. Let's make sure before we traverse into a directory that it is not a mount point (or junction). This addresses https://github.com/git-for-windows/git/issues/607 Signed-off-by: Johannes Schindelin --- builtin/clean.c | 14 ++++++++++++++ cache.h | 1 + compat/mingw.c | 22 ++++++++++++++++++++++ compat/mingw.h | 3 +++ git-compat-util.h | 4 ++++ path.c | 39 +++++++++++++++++++++++++++++++++++++++ t/t7300-clean.sh | 9 +++++++++ 7 files changed, 92 insertions(+) diff --git a/builtin/clean.c b/builtin/clean.c index 5abf087e7c..fbbc55cb7e 100644 --- a/builtin/clean.c +++ b/builtin/clean.c @@ -33,6 +33,8 @@ static const char *msg_remove = N_("Removing %s\n"); static const char *msg_would_remove = N_("Would remove %s\n"); static const char *msg_skip_git_dir = N_("Skipping repository %s\n"); static const char *msg_would_skip_git_dir = N_("Would skip repository %s\n"); +static const char *msg_skip_mount_point = N_("Skipping mount point %s\n"); +static const char *msg_would_skip_mount_point = N_("Would skip mount point %s\n"); static const char *msg_warn_remove_failed = N_("failed to remove %s"); static const char *msg_warn_lstat_failed = N_("could not lstat %s\n"); @@ -170,6 +172,18 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag, goto out; } + if (is_mount_point(path)) { + if (!quiet) { + quote_path_relative(path->buf, prefix, "ed); + printf(dry_run ? + _(msg_would_skip_mount_point) : + _(msg_skip_mount_point), quoted.buf); + } + *dir_gone = 0; + + goto out; + } + dir = opendir(path->buf); if (!dir) { /* an empty dir could be removed even if it is unreadble */ diff --git a/cache.h b/cache.h index 04cabaac11..6448398cb3 100644 --- a/cache.h +++ b/cache.h @@ -1288,6 +1288,7 @@ int normalize_path_copy_len(char *dst, const char *src, int *prefix_len); int normalize_path_copy(char *dst, const char *src); int longest_ancestor_length(const char *path, struct string_list *prefixes); char *strip_path_suffix(const char *path, const char *suffix); +int is_mount_point_via_stat(struct strbuf *path); int daemon_avoid_alias(const char *path); /* diff --git a/compat/mingw.c b/compat/mingw.c index fe609239dd..1ba0dbbf08 100644 --- a/compat/mingw.c +++ b/compat/mingw.c @@ -2229,6 +2229,28 @@ pid_t waitpid(pid_t pid, int *status, int options) return -1; } +int mingw_is_mount_point(struct strbuf *path) +{ + WIN32_FIND_DATAW findbuf = { 0 }; + HANDLE handle; + wchar_t wfilename[MAX_PATH]; + int wlen = xutftowcs_path(wfilename, path->buf); + if (wlen < 0) + die(_("could not get long path for '%s'"), path->buf); + + /* remove trailing slash, if any */ + if (wlen > 0 && wfilename[wlen - 1] == L'/') + wfilename[--wlen] = L'\0'; + + handle = FindFirstFileW(wfilename, &findbuf); + if (handle == INVALID_HANDLE_VALUE) + return 0; + FindClose(handle); + + return (findbuf.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) && + (findbuf.dwReserved0 == IO_REPARSE_TAG_MOUNT_POINT); +} + int xutftowcsn(wchar_t *wcs, const char *utfs, size_t wcslen, int utflen) { int upos = 0, wpos = 0; diff --git a/compat/mingw.h b/compat/mingw.h index 9ad204c57c..338e8c0bf6 100644 --- a/compat/mingw.h +++ b/compat/mingw.h @@ -442,6 +442,9 @@ static inline void convert_slashes(char *path) if (*path == '\\') *path = '/'; } +struct strbuf; +int mingw_is_mount_point(struct strbuf *path); +#define is_mount_point mingw_is_mount_point #define PATH_SEP ';' char *mingw_query_user_email(void); #define query_user_email mingw_query_user_email diff --git a/git-compat-util.h b/git-compat-util.h index 607dca7534..35eaa9defa 100644 --- a/git-compat-util.h +++ b/git-compat-util.h @@ -405,6 +405,10 @@ static inline char *git_find_last_dir_sep(const char *path) #define find_last_dir_sep git_find_last_dir_sep #endif +#ifndef is_mount_point +#define is_mount_point is_mount_point_via_stat +#endif + #ifndef query_user_email #define query_user_email() NULL #endif diff --git a/path.c b/path.c index e3da1f3c4e..38a3115b41 100644 --- a/path.c +++ b/path.c @@ -1269,6 +1269,45 @@ char *strip_path_suffix(const char *path, const char *suffix) return offset == -1 ? NULL : xstrndup(path, offset); } +int is_mount_point_via_stat(struct strbuf *path) +{ + size_t len = path->len; + unsigned int current_dev; + struct stat st; + + if (!strcmp("/", path->buf)) + return 1; + + strbuf_addstr(path, "/."); + if (lstat(path->buf, &st)) { + /* + * If we cannot access the current directory, we cannot say + * that it is a bind mount. + */ + strbuf_setlen(path, len); + return 0; + } + current_dev = st.st_dev; + + /* Now look at the parent directory */ + strbuf_addch(path, '.'); + if (lstat(path->buf, &st)) { + /* + * If we cannot access the parent directory, we cannot say + * that it is a bind mount. + */ + strbuf_setlen(path, len); + return 0; + } + strbuf_setlen(path, len); + + /* + * If the device ID differs between current and parent directory, + * then it is a bind mount. + */ + return current_dev != st.st_dev; +} + int daemon_avoid_alias(const char *p) { int sl, ndot; diff --git a/t/t7300-clean.sh b/t/t7300-clean.sh index 6e6d24c1c3..a4b2898558 100755 --- a/t/t7300-clean.sh +++ b/t/t7300-clean.sh @@ -737,4 +737,13 @@ test_expect_success MINGW 'handle clean & core.longpaths = false nicely' ' test_i18ngrep "too long" .git/err ' +test_expect_success MINGW 'clean does not traverse mount points' ' + mkdir target && + >target/dont-clean-me && + git init with-mountpoint && + cmd //c "mklink /j with-mountpoint\\mountpoint target" && + git -C with-mountpoint clean -dfx && + test_path_is_file target/dont-clean-me +' + test_done From cfaed7098447c5d3e5a86d73c4a8dc58ae689ef4 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Tue, 11 Dec 2018 12:55:26 +0100 Subject: [PATCH 2/2] clean: remove mount points when possible Windows' equivalent to "bind mounts", NTFS junction points, can be unlinked without affecting the mount target. This is clearly what users expect to happen when they call `git clean -dfx` in a worktree that contains NTFS junction points: the junction should be removed, and the target directory of said junction should be left alone (unless it is inside the worktree). Signed-off-by: Johannes Schindelin --- builtin/clean.c | 13 +++++++++++++ compat/mingw.h | 1 + t/t7300-clean.sh | 1 + 3 files changed, 15 insertions(+) diff --git a/builtin/clean.c b/builtin/clean.c index fbbc55cb7e..daf591584f 100644 --- a/builtin/clean.c +++ b/builtin/clean.c @@ -33,8 +33,10 @@ static const char *msg_remove = N_("Removing %s\n"); static const char *msg_would_remove = N_("Would remove %s\n"); static const char *msg_skip_git_dir = N_("Skipping repository %s\n"); static const char *msg_would_skip_git_dir = N_("Would skip repository %s\n"); +#ifndef CAN_UNLINK_MOUNT_POINTS static const char *msg_skip_mount_point = N_("Skipping mount point %s\n"); static const char *msg_would_skip_mount_point = N_("Would skip mount point %s\n"); +#endif static const char *msg_warn_remove_failed = N_("failed to remove %s"); static const char *msg_warn_lstat_failed = N_("could not lstat %s\n"); @@ -173,6 +175,7 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag, } if (is_mount_point(path)) { +#ifndef CAN_UNLINK_MOUNT_POINTS if (!quiet) { quote_path_relative(path->buf, prefix, "ed); printf(dry_run ? @@ -180,6 +183,16 @@ static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag, _(msg_skip_mount_point), quoted.buf); } *dir_gone = 0; +#else + if (!dry_run && unlink(path->buf)) { + int saved_errno = errno; + quote_path_relative(path->buf, prefix, "ed); + errno = saved_errno; + warning_errno(_(msg_warn_remove_failed), quoted.buf); + *dir_gone = 0; + ret = -1; + } +#endif goto out; } diff --git a/compat/mingw.h b/compat/mingw.h index 338e8c0bf6..54a0987af3 100644 --- a/compat/mingw.h +++ b/compat/mingw.h @@ -445,6 +445,7 @@ static inline void convert_slashes(char *path) struct strbuf; int mingw_is_mount_point(struct strbuf *path); #define is_mount_point mingw_is_mount_point +#define CAN_UNLINK_MOUNT_POINTS 1 #define PATH_SEP ';' char *mingw_query_user_email(void); #define query_user_email mingw_query_user_email diff --git a/t/t7300-clean.sh b/t/t7300-clean.sh index a4b2898558..1aee0d5949 100755 --- a/t/t7300-clean.sh +++ b/t/t7300-clean.sh @@ -743,6 +743,7 @@ test_expect_success MINGW 'clean does not traverse mount points' ' git init with-mountpoint && cmd //c "mklink /j with-mountpoint\\mountpoint target" && git -C with-mountpoint clean -dfx && + test_path_is_missing with-mountpoint/mountpoint && test_path_is_file target/dont-clean-me '