From c23d78266cdd45042809bd5d9934670464a5083d Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Fri, 31 Jan 2020 12:02:47 +0100 Subject: [PATCH 1/3] mingw: demonstrate a `git add` issue with NTFS junctions NTFS junctions are somewhat similar in spirit to Unix bind mounts: they point to a different directory and are resolved by the filesystem driver. As such, they appear to `lstat()` as if they are directories, not as if they are symbolic links. _Any_ user can create junctions, while symbolic links can only be created by non-administrators in Developer Mode on Windows 10. Hence NTFS junctions are much more common "in the wild" than NTFS symbolic links. It was reported in https://github.com/git-for-windows/git/issues/2481 that adding files via an absolute path that traverses an NTFS junction: since 1e64d18 (mingw: do resolve symlinks in `getcwd()`), we resolve not only symbolic links but also NTFS junctions when determining the absolute path of the current directory. The same is not true for `git add `, where symbolic links are resolved in ``, but not NTFS junctions. Signed-off-by: Johannes Schindelin --- t/t3700-add.sh | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/t/t3700-add.sh b/t/t3700-add.sh index df580a5806..d934f3417f 100755 --- a/t/t3700-add.sh +++ b/t/t3700-add.sh @@ -548,4 +548,15 @@ test_expect_success CASE_INSENSITIVE_FS 'path is case-insensitive' ' git add "$downcased" ' +test_expect_failure MINGW 'can add files via NTFS junctions' ' + test_when_finished "cmd //c rmdir junction && rm -rf target" && + test_create_repo target && + cmd //c "mklink /j junction target" && + >target/via-junction && + git -C junction add "$(pwd)/junction/via-junction" && + echo via-junction >expect && + git -C target diff --cached --name-only >actual && + test_cmp expect actual +' + test_done From 6811e1d2f5ec0ae80a6468eb0fb32bf1b0fc8e7f Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Fri, 31 Jan 2020 11:44:31 +0100 Subject: [PATCH 2/3] strbuf_realpath(): use platform-dependent API if available Some platforms (e.g. Windows) provide API functions to resolve paths much quicker. Let's offer a way to short-cut `strbuf_realpath()` on those platforms. Signed-off-by: Johannes Schindelin --- abspath.c | 3 +++ git-compat-util.h | 4 ++++ 2 files changed, 7 insertions(+) diff --git a/abspath.c b/abspath.c index 1202cde23d..0c17e98654 100644 --- a/abspath.c +++ b/abspath.c @@ -93,6 +93,9 @@ static char *strbuf_realpath_1(struct strbuf *resolved, const char *path, goto error_out; } + if (platform_strbuf_realpath(resolved, path)) + return resolved->buf; + strbuf_addstr(&remaining, path); get_root_part(resolved, &remaining); diff --git a/git-compat-util.h b/git-compat-util.h index 4678e21c4c..cd1d21a189 100644 --- a/git-compat-util.h +++ b/git-compat-util.h @@ -387,6 +387,10 @@ static inline int git_has_dir_sep(const char *path) #define query_user_email() NULL #endif +#ifndef platform_strbuf_realpath +#define platform_strbuf_realpath(resolved, path) NULL +#endif + #ifdef __TANDEM #include #include From a6c62f19c99e5f7f62d56cd7da10da01d81af1c1 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Fri, 31 Jan 2020 11:49:04 +0100 Subject: [PATCH 3/3] mingw: implement a platform-specific `strbuf_realpath()` There is a Win32 API function to resolve symbolic links, and we can use that instead of resolving them manually. Even better, this function also resolves NTFS junction points (which are somewhat similar to bind mounts). This fixes https://github.com/git-for-windows/git/issues/2481. Signed-off-by: Johannes Schindelin --- compat/mingw.c | 76 +++++++++++++++++++++++++++++++++++++++++++ compat/mingw.h | 3 ++ t/t0060-path-utils.sh | 8 +++++ t/t3700-add.sh | 2 +- t/t5601-clone.sh | 7 ++++ 5 files changed, 95 insertions(+), 1 deletion(-) diff --git a/compat/mingw.c b/compat/mingw.c index 8a9972a1ca..2b5cfd6346 100644 --- a/compat/mingw.c +++ b/compat/mingw.c @@ -1230,6 +1230,82 @@ struct tm *localtime_r(const time_t *timep, struct tm *result) } #endif +char *mingw_strbuf_realpath(struct strbuf *resolved, const char *path) +{ + wchar_t wpath[MAX_PATH]; + HANDLE h; + DWORD ret; + int len; + const char *last_component = NULL; + char *append = NULL; + + if (xutftowcs_path(wpath, path) < 0) + return NULL; + + h = CreateFileW(wpath, 0, + FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL, + OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL); + + /* + * strbuf_realpath() allows the last path component to not exist. If + * that is the case, now it's time to try without last component. + */ + if (h == INVALID_HANDLE_VALUE && + GetLastError() == ERROR_FILE_NOT_FOUND) { + /* cut last component off of `wpath` */ + wchar_t *p = wpath + wcslen(wpath); + + while (p != wpath) + if (*(--p) == L'/' || *p == L'\\') + break; /* found start of last component */ + + if (p != wpath && (last_component = find_last_dir_sep(path))) { + append = xstrdup(last_component + 1); /* skip directory separator */ + /* + * Do not strip the trailing slash at the drive root, otherwise + * the path would be e.g. `C:` (which resolves to the + * _current_ directory on that drive). + */ + if (p[-1] == L':') + p[1] = L'\0'; + else + *p = L'\0'; + h = CreateFileW(wpath, 0, FILE_SHARE_READ | + FILE_SHARE_WRITE | FILE_SHARE_DELETE, + NULL, OPEN_EXISTING, + FILE_FLAG_BACKUP_SEMANTICS, NULL); + } + } + + if (h == INVALID_HANDLE_VALUE) { +realpath_failed: + FREE_AND_NULL(append); + return NULL; + } + + ret = GetFinalPathNameByHandleW(h, wpath, ARRAY_SIZE(wpath), 0); + CloseHandle(h); + if (!ret || ret >= ARRAY_SIZE(wpath)) + goto realpath_failed; + + len = wcslen(wpath) * 3; + strbuf_grow(resolved, len); + len = xwcstoutf(resolved->buf, normalize_ntpath(wpath), len); + if (len < 0) + goto realpath_failed; + resolved->len = len; + + if (append) { + /* Use forward-slash, like `normalize_ntpath()` */ + strbuf_complete(resolved, '/'); + strbuf_addstr(resolved, append); + FREE_AND_NULL(append); + } + + return resolved->buf; + +} + char *mingw_getcwd(char *pointer, int len) { wchar_t cwd[MAX_PATH], wpointer[MAX_PATH]; diff --git a/compat/mingw.h b/compat/mingw.h index 444daedfa5..f6daf47ee4 100644 --- a/compat/mingw.h +++ b/compat/mingw.h @@ -39,6 +39,9 @@ static inline void convert_slashes(char *path) #define PATH_SEP ';' char *mingw_query_user_email(void); #define query_user_email mingw_query_user_email +struct strbuf; +char *mingw_strbuf_realpath(struct strbuf *resolved, const char *path); +#define platform_strbuf_realpath mingw_strbuf_realpath /** * Verifies that the specified path is owned by the user running the diff --git a/t/t0060-path-utils.sh b/t/t0060-path-utils.sh index 8545cdfab5..eb2ab9d437 100755 --- a/t/t0060-path-utils.sh +++ b/t/t0060-path-utils.sh @@ -281,6 +281,14 @@ test_expect_success SYMLINKS 'real path works on symlinks' ' test_cmp expect actual ' +test_expect_success MINGW 'real path works near drive root' ' + # we need a non-existing path at the drive root; simply skip if C:/xyz exists + if test ! -e C:/xyz + then + test C:/xyz = $(test-tool path-utils real_path C:/xyz) + fi +' + test_expect_success SYMLINKS 'prefix_path works with absolute paths to work tree symlinks' ' ln -s target symlink && echo "symlink" >expect && diff --git a/t/t3700-add.sh b/t/t3700-add.sh index d934f3417f..10185f31f0 100755 --- a/t/t3700-add.sh +++ b/t/t3700-add.sh @@ -548,7 +548,7 @@ test_expect_success CASE_INSENSITIVE_FS 'path is case-insensitive' ' git add "$downcased" ' -test_expect_failure MINGW 'can add files via NTFS junctions' ' +test_expect_success MINGW 'can add files via NTFS junctions' ' test_when_finished "cmd //c rmdir junction && rm -rf target" && test_create_repo target && cmd //c "mklink /j junction target" && diff --git a/t/t5601-clone.sh b/t/t5601-clone.sh index d743d986c4..f70d99016e 100755 --- a/t/t5601-clone.sh +++ b/t/t5601-clone.sh @@ -78,6 +78,13 @@ test_expect_success 'clone respects GIT_WORK_TREE' ' ' +test_expect_success CASE_INSENSITIVE_FS 'core.worktree is not added due to path case' ' + + mkdir UPPERCASE && + git clone src "$(pwd)/uppercase" && + test "unset" = "$(git -C UPPERCASE config --default unset core.worktree)" +' + test_expect_success 'clone from hooks' ' test_create_repo r0 &&