Merge pull request #4713 from libgit2/ethomson/win_symlinks

Support symlinks on Windows when core.symlinks=true

src/CMakeLists.txt

@@ -423,7 +423,7 @@ FILE(GLOB SRC_H
 
 # On Windows use specific platform sources
 IF (WIN32 AND NOT CYGWIN)
-	ADD_DEFINITIONS(-DWIN32 -D_WIN32_WINNT=0x0501)
+	ADD_DEFINITIONS(-DWIN32 -D_WIN32_WINNT=0x0600)
 
 	IF(MSVC)
 		SET(WIN_RC "win32/git2.rc")

src/repository.c

@@ -944,18 +944,20 @@ static int load_config(
 	git_buf config_path = GIT_BUF_INIT;
 	git_config *cfg = NULL;
 
-	assert(repo && out);
+	assert(out);
 
 	if ((error = git_config_new(&cfg)) < 0)
 		return error;
 
-	if ((error = git_repository_item_path(&config_path, repo, GIT_REPOSITORY_ITEM_CONFIG)) == 0)
-		error = git_config_add_file_ondisk(cfg, config_path.ptr, GIT_CONFIG_LEVEL_LOCAL, repo, 0);
+	if (repo) {
+		if ((error = git_repository_item_path(&config_path, repo, GIT_REPOSITORY_ITEM_CONFIG)) == 0)
+			error = git_config_add_file_ondisk(cfg, config_path.ptr, GIT_CONFIG_LEVEL_LOCAL, repo, 0);
 
-	if (error && error != GIT_ENOTFOUND)
-		goto on_error;
+		if (error && error != GIT_ENOTFOUND)
+			goto on_error;
 
-	git_buf_dispose(&config_path);
+		git_buf_dispose(&config_path);
+	}
 
 	if (global_config_path != NULL &&
 		(error = git_config_add_file_ondisk(
@@ -1411,24 +1413,56 @@ static bool is_filesystem_case_insensitive(const char *gitdir_path)
 
 static bool are_symlinks_supported(const char *wd_path)
 {
+	git_config *config = NULL;
 	git_buf path = GIT_BUF_INIT;
 	int fd;
 	struct stat st;
-	int symlinks_supported = -1;
+	bool symlinks = false;
+
+	/*
+	 * To emulate Git for Windows, symlinks on Windows must be explicitly
+	 * opted-in.  We examine the system configuration for a core.symlinks
+	 * set to true.  If found, we then examine the filesystem to see if
+	 * symlinks are _actually_ supported by the current user.  If that is
+	 * _not_ set, then we do not test or enable symlink support.
+	 */
+#ifdef GIT_WIN32
+	git_buf global_buf = GIT_BUF_INIT;
+	git_buf xdg_buf = GIT_BUF_INIT;
+	git_buf system_buf = GIT_BUF_INIT;
+	git_buf programdata_buf = GIT_BUF_INIT;
+
+	git_config_find_global(&global_buf);
+	git_config_find_xdg(&xdg_buf);
+	git_config_find_system(&system_buf);
+	git_config_find_programdata(&programdata_buf);
+
+	if (load_config(&config, NULL,
+	    path_unless_empty(&global_buf),
+	    path_unless_empty(&xdg_buf),
+	    path_unless_empty(&system_buf),
+	    path_unless_empty(&programdata_buf)) < 0)
+		goto done;
+
+	if (git_config_get_bool(&symlinks, config, "core.symlinks") < 0 || !symlinks)
+		goto done;
+#endif
 
 	if ((fd = git_futils_mktmp(&path, wd_path, 0666)) < 0 ||
-		p_close(fd) < 0 ||
-		p_unlink(path.ptr) < 0 ||
-		p_symlink("testing", path.ptr) < 0 ||
-		p_lstat(path.ptr, &st) < 0)
-		symlinks_supported = false;
-	else
-		symlinks_supported = (S_ISLNK(st.st_mode) != 0);
+	    p_close(fd) < 0 ||
+	    p_unlink(path.ptr) < 0 ||
+	    p_symlink("testing", path.ptr) < 0 ||
+	    p_lstat(path.ptr, &st) < 0)
+		goto done;
+
+	symlinks = (S_ISLNK(st.st_mode) != 0);
 
 	(void)p_unlink(path.ptr);
-	git_buf_dispose(&path);
 
-	return symlinks_supported;
+done:
+	git_buf_dispose(&path);
+	git_config_free(config);
+	return symlinks;
 }
 
 static int create_empty_file(const char *path, mode_t mode)

src/win32/posix_w32.c

@@ -29,15 +29,16 @@
 #define IO_REPARSE_TAG_SYMLINK (0xA000000CL)
 #endif
 
+#ifndef SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE
+# define SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE 0x02
+#endif
+
 /* Allowable mode bits on Win32.  Using mode bits that are not supported on
  * Win32 (eg S_IRWXU) is generally ignored, but Wine warns loudly about it
  * so we simply remove them.
  */
 #define WIN32_MODE_MASK (_S_IREAD | _S_IWRITE)
 
-/* GetFinalPathNameByHandleW signature */
-typedef DWORD(WINAPI *PFGetFinalPathNameByHandleW)(HANDLE, LPWSTR, DWORD, DWORD);
-
 unsigned long git_win32__createfile_sharemode =
  FILE_SHARE_READ | FILE_SHARE_WRITE;
 int git_win32__retries = 10;
@@ -393,12 +394,20 @@ int p_readlink(const char *path, char *buf, size_t bufsiz)
 	return (int)bufsiz;
 }
 
-int p_symlink(const char *old, const char *new)
+int p_symlink(const char *target, const char *path)
 {
-	/* Real symlinks on NTFS require admin privileges. Until this changes,
-	 * libgit2 just creates a text file with the link target in the contents.
-	 */
-	return git_futils_fake_symlink(old, new);
+	git_win32_path target_w, path_w;
+	wchar_t *target_p;
+
+	if (git_win32_path_from_utf8(path_w, path) < 0 ||
+		git__utf8_to_16(target_w, MAX_PATH, target) < 0)
+		return -1;
+
+	if (!CreateSymbolicLinkW(path_w, target_w,
+	    SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE))
+		return -1;
+
+	return 0;
 }
 
 struct open_opts {
@@ -598,40 +607,13 @@ int p_getcwd(char *buffer_out, size_t size)
 	return 0;
 }
 
-/*
- * Returns the address of the GetFinalPathNameByHandleW function.
- * This function is available on Windows Vista and higher.
- */
-static PFGetFinalPathNameByHandleW get_fpnbyhandle(void)
-{
-	static PFGetFinalPathNameByHandleW pFunc = NULL;
-	PFGetFinalPathNameByHandleW toReturn = pFunc;
-
-	if (!toReturn) {
-		HMODULE hModule = GetModuleHandleW(L"kernel32");
-
-		if (hModule)
-			toReturn = (PFGetFinalPathNameByHandleW)GetProcAddress(hModule, "GetFinalPathNameByHandleW");
-
-		pFunc = toReturn;
-	}
-
-	assert(toReturn);
-
-	return toReturn;
-}
-
 static int getfinalpath_w(
 	git_win32_path dest,
 	const wchar_t *path)
 {
-	PFGetFinalPathNameByHandleW pgfp = get_fpnbyhandle();
 	HANDLE hFile;
 	DWORD dwChars;
 
-	if (!pgfp)
-		return -1;
-
 	/* Use FILE_FLAG_BACKUP_SEMANTICS so we can open a directory. Do not
 	* specify FILE_FLAG_OPEN_REPARSE_POINT; we want to open a handle to the
 	* target of the link. */
@@ -642,7 +624,7 @@ static int getfinalpath_w(
 		return -1;
 
 	/* Call GetFinalPathNameByHandle */
-	dwChars = pgfp(hFile, dest, GIT_WIN_PATH_UTF16, FILE_NAME_NORMALIZED);
+	dwChars = GetFinalPathNameByHandleW(hFile, dest, GIT_WIN_PATH_UTF16, FILE_NAME_NORMALIZED);
 	CloseHandle(hFile);
 
 	if (!dwChars || dwChars >= GIT_WIN_PATH_UTF16)

tests/checkout/conflict.c

@@ -2,6 +2,7 @@
 #include "git2/repository.h"
 #include "git2/sys/index.h"
 #include "fileops.h"
+#include "repository.h"
 
 static git_repository *g_repo;
 static git_index *g_index;
@@ -184,28 +185,35 @@ static void ensure_workdir(const char *path, int mode, const char *oid_str)
 	ensure_workdir_oid(path, oid_str);
 }
 
-static void ensure_workdir_link(const char *path, const char *target)
+static void ensure_workdir_link(
+	git_repository *repo,
+	const char *path,
+	const char *target)
 {
-#ifdef GIT_WIN32
-	ensure_workdir_contents(path, target);
-#else
-	git_buf fullpath = GIT_BUF_INIT;
-	char actual[1024];
-	struct stat st;
-	int len;
+	int symlinks;
 
-	cl_git_pass(
-		git_buf_joinpath(&fullpath, git_repository_workdir(g_repo), path));
+	cl_git_pass(git_repository__cvar(&symlinks, repo, GIT_CVAR_SYMLINKS));
 
-	cl_git_pass(p_lstat(git_buf_cstr(&fullpath), &st));
-	cl_assert(S_ISLNK(st.st_mode));
+	if (!symlinks) {
+		ensure_workdir_contents(path, target);
+	} else {
+		git_buf fullpath = GIT_BUF_INIT;
+		char actual[1024];
+		struct stat st;
+		int len;
 
-	cl_assert((len = p_readlink(git_buf_cstr(&fullpath), actual, 1024)) > 0);
-	actual[len] = '\0';
-	cl_assert(strcmp(actual, target) == 0);
+		cl_git_pass(
+			git_buf_joinpath(&fullpath, git_repository_workdir(g_repo), path));
 
-	git_buf_dispose(&fullpath);
-#endif
+		cl_git_pass(p_lstat(git_buf_cstr(&fullpath), &st));
+		cl_assert(S_ISLNK(st.st_mode));
+
+		cl_assert((len = p_readlink(git_buf_cstr(&fullpath), actual, 1024)) > 0);
+		actual[len] = '\0';
+		cl_assert(strcmp(actual, target) == 0);
+
+		git_buf_dispose(&fullpath);
+	}
 }
 
 void test_checkout_conflict__ignored(void)
@@ -415,8 +423,8 @@ void test_checkout_conflict__links(void)
 	cl_git_pass(git_checkout_index(g_repo, g_index, &opts));
 
 	/* Conflicts with links always keep the ours side (even with -Xtheirs) */
-	ensure_workdir_link("link-1", LINK_OURS_TARGET);
-	ensure_workdir_link("link-2", LINK_OURS_TARGET);
+	ensure_workdir_link(g_repo, "link-1", LINK_OURS_TARGET);
+	ensure_workdir_link(g_repo, "link-2", LINK_OURS_TARGET);
 }
 
 void test_checkout_conflict__add_add(void)
@@ -684,7 +692,7 @@ void test_checkout_conflict__renames(void)
 void test_checkout_conflict__rename_keep_ours(void)
 {
 	git_checkout_options opts = GIT_CHECKOUT_OPTIONS_INIT;
-	
+
 	struct checkout_index_entry checkout_index_entries[] = {
 		{ 0100644, "68c6c84b091926c7d90aa6a79b2bc3bb6adccd8e", 0, "0a-no-change.txt" },
 		{ 0100644, "f0ce2b8e4986084d9b308fb72709e414c23eb5e6", 0, "0b-duplicated-in-ours.txt" },
@@ -728,122 +736,122 @@ void test_checkout_conflict__rename_keep_ours(void)
 		{ 0100644, "b42712cfe99a1a500b2a51fe984e0b8a7702ba11", 2, "7-both-renamed.txt" },
 		{ 0100644, "b69fe837e4cecfd4c9a40cdca7c138468687df07", 3, "7-both-renamed.txt" }
 	};
-	
+
 	struct checkout_name_entry checkout_name_entries[] = {
 		{
 			"3a-renamed-in-ours-deleted-in-theirs.txt",
 			"3a-newname-in-ours-deleted-in-theirs.txt",
 			""
 		},
-		
+
 		{
 			"3b-renamed-in-theirs-deleted-in-ours.txt",
 			"",
 			"3b-newname-in-theirs-deleted-in-ours.txt"
 		},
-		
+
 		{
 			"4a-renamed-in-ours-added-in-theirs.txt",
 			"4a-newname-in-ours-added-in-theirs.txt",
 			""
 		},
-		
+
 		{
 			"4b-renamed-in-theirs-added-in-ours.txt",
 			"",
 			"4b-newname-in-theirs-added-in-ours.txt"
 		},
-		
+
 		{
 			"5a-renamed-in-ours-added-in-theirs.txt",
 			"5a-newname-in-ours-added-in-theirs.txt",
 			"5a-renamed-in-ours-added-in-theirs.txt"
 		},
-		
+
 		{
 			"5b-renamed-in-theirs-added-in-ours.txt",
 			"5b-renamed-in-theirs-added-in-ours.txt",
 			"5b-newname-in-theirs-added-in-ours.txt"
 		},
-		
+
 		{
 			"6-both-renamed-1-to-2.txt",
 			"6-both-renamed-1-to-2-ours.txt",
 			"6-both-renamed-1-to-2-theirs.txt"
 		},
-		
+
 		{
 			"7-both-renamed-side-1.txt",
 			"7-both-renamed.txt",
 			"7-both-renamed-side-1.txt"
 		},
-		
+
 		{
 			"7-both-renamed-side-2.txt",
 			"7-both-renamed-side-2.txt",
 			"7-both-renamed.txt"
 		}
 	};
-	
+
 	opts.checkout_strategy |= GIT_CHECKOUT_SAFE | GIT_CHECKOUT_USE_OURS;
-	
+
 	create_index(checkout_index_entries, 41);
 	create_index_names(checkout_name_entries, 9);
 	cl_git_pass(git_index_write(g_index));
-	
+
 	cl_git_pass(git_checkout_index(g_repo, g_index, &opts));
-		
+
 	ensure_workdir("0a-no-change.txt",
 				   0100644, "68c6c84b091926c7d90aa6a79b2bc3bb6adccd8e");
-	
+
 	ensure_workdir("0b-duplicated-in-ours.txt",
 				   0100644, "f0ce2b8e4986084d9b308fb72709e414c23eb5e6");
-	
+
 	ensure_workdir("0b-rewritten-in-ours.txt",
 				   0100644, "e376fbdd06ebf021c92724da9f26f44212734e3e");
-	
+
 	ensure_workdir("0c-duplicated-in-theirs.txt",
 				   0100644, "2f56120107d680129a5d9791b521cb1e73a2ed31");
-	
+
 	ensure_workdir("0c-rewritten-in-theirs.txt",
 				   0100644, "efc9121fdedaf08ba180b53ebfbcf71bd488ed09");
-	
+
 	ensure_workdir("1a-newname-in-ours-edited-in-theirs.txt",
 				   0100644, "0d872f8e871a30208305978ecbf9e66d864f1638");
-	
+
 	ensure_workdir("1a-newname-in-ours.txt",
 				   0100644, "d0d4594e16f2e19107e3fa7ea63e7aaaff305ffb");
-	
+
 	ensure_workdir("1b-newname-in-theirs-edited-in-ours.txt",
 				   0100644, "ed9523e62e453e50dd9be1606af19399b96e397a");
-	
+
 	ensure_workdir("1b-newname-in-theirs.txt",
 				   0100644, "2b5f1f181ee3b58ea751f5dd5d8f9b445520a136");
-	
+
 	ensure_workdir("2-newname-in-both.txt",
 				   0100644, "178940b450f238a56c0d75b7955cb57b38191982");
 
 	ensure_workdir("3a-newname-in-ours-deleted-in-theirs.txt",
 				   0100644, "18cb316b1cefa0f8a6946f0e201a8e1a6f845ab9");
-	
+
 	ensure_workdir("3b-newname-in-theirs-deleted-in-ours.txt",
 				   0100644, "36219b49367146cb2e6a1555b5a9ebd4d0328495");
-	
+
 	ensure_workdir("4a-newname-in-ours-added-in-theirs.txt",
 				   0100644, "227792b52aaa0b238bea00ec7e509b02623f168c");
-	
+
 	ensure_workdir("4b-newname-in-theirs-added-in-ours.txt",
 				   0100644, "de872ee3618b894992e9d1e18ba2ebe256a112f9");
-	
+
 	ensure_workdir("5a-newname-in-ours-added-in-theirs.txt",
 				   0100644, "d3719a5ae8e4d92276b5313ce976f6ee5af2b436");
-		
+
 	ensure_workdir("5b-newname-in-theirs-added-in-ours.txt",
 				   0100644, "385c8a0f26ddf79e9041e15e17dc352ed2c4cced");
 
 	ensure_workdir("6-both-renamed-1-to-2-ours.txt",
 				   0100644, "d8fa77b6833082c1ea36b7828a582d4c43882450");
-	
+
 	ensure_workdir("7-both-renamed.txt",
 				   0100644, "b42712cfe99a1a500b2a51fe984e0b8a7702ba11");
 }

tests/checkout/icase.c

@@ -3,6 +3,7 @@
 #include "git2/checkout.h"
 #include "refs.h"
 #include "path.h"
+#include "repository.h"
 
 #ifdef GIT_WIN32
 # include <windows.h>
@@ -44,29 +45,6 @@ void test_checkout_icase__cleanup(void)
 
 static char *get_filename(const char *in)
 {
-#ifdef GIT_WIN32
-	HANDLE fh;
-	HMODULE kerneldll;
-	char *filename;
-
-	typedef DWORD (__stdcall *getfinalpathname)(HANDLE, LPSTR, DWORD, DWORD);
-	getfinalpathname getfinalpathfn;
-
-	cl_assert(filename = malloc(MAX_PATH));
-	cl_assert(kerneldll = LoadLibrary("kernel32.dll"));
-	cl_assert(getfinalpathfn = (getfinalpathname)GetProcAddress(kerneldll, "GetFinalPathNameByHandleA"));
-
-	cl_assert(fh = CreateFileA(in, FILE_READ_ATTRIBUTES | STANDARD_RIGHTS_READ, FILE_SHARE_READ,
-		NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL));
-
-	cl_win32_pass(getfinalpathfn(fh, filename, MAX_PATH, VOLUME_NAME_DOS));
-
-	CloseHandle(fh);
-
-	git_path_mkposix(filename);
-
-	return filename;
-#else
 	char *search_dirname, *search_filename, *filename = NULL;
 	git_buf out = GIT_BUF_INIT;
 	DIR *dir;
@@ -92,7 +70,6 @@ static char *get_filename(const char *in)
 	git_buf_dispose(&out);
 
 	return filename;
-#endif
 }
 
 static void assert_name_is(const char *expected)
@@ -115,6 +92,18 @@ static void assert_name_is(const char *expected)
 	free(actual);
 }
 
+static int symlink_or_fake(git_repository *repo, const char *a, const char *b)
+{
+	int symlinks;
+
+	cl_git_pass(git_repository__cvar(&symlinks, repo, GIT_CVAR_SYMLINKS));
+
+	if (symlinks)
+		return p_symlink(a, b);
+	else
+		return git_futils_fake_symlink(a, b);
+}
+
 void test_checkout_icase__refuses_to_overwrite_files_for_files(void)
 {
 	checkout_opts.checkout_strategy = GIT_CHECKOUT_SAFE|GIT_CHECKOUT_RECREATE_MISSING;
@@ -141,7 +130,7 @@ void test_checkout_icase__refuses_to_overwrite_links_for_files(void)
 {
 	checkout_opts.checkout_strategy = GIT_CHECKOUT_SAFE|GIT_CHECKOUT_RECREATE_MISSING;
 
-	cl_must_pass(p_symlink("../tmp", "testrepo/BRANCH_FILE.txt"));
+	cl_must_pass(symlink_or_fake(repo, "../tmp", "testrepo/BRANCH_FILE.txt"));
 
 	cl_git_fail(git_checkout_tree(repo, obj, &checkout_opts));
 
@@ -153,7 +142,7 @@ void test_checkout_icase__overwrites_links_for_files_when_forced(void)
 {
 	checkout_opts.checkout_strategy = GIT_CHECKOUT_FORCE;
 
-	cl_must_pass(p_symlink("../tmp", "testrepo/NEW.txt"));
+	cl_must_pass(symlink_or_fake(repo, "../tmp", "testrepo/NEW.txt"));
 
 	cl_git_pass(git_checkout_tree(repo, obj, &checkout_opts));
 
@@ -229,7 +218,7 @@ void test_checkout_icase__refuses_to_overwrite_links_for_folders(void)
 {
 	checkout_opts.checkout_strategy = GIT_CHECKOUT_SAFE|GIT_CHECKOUT_RECREATE_MISSING;
 
-	cl_must_pass(p_symlink("..", "testrepo/A"));
+	cl_must_pass(symlink_or_fake(repo, "..", "testrepo/A"));
 
 	cl_git_fail(git_checkout_tree(repo, obj, &checkout_opts));
 
@@ -241,7 +230,7 @@ void test_checkout_icase__overwrites_links_for_folders_when_forced(void)
 {
 	checkout_opts.checkout_strategy = GIT_CHECKOUT_FORCE;
 
-	cl_must_pass(p_symlink("..", "testrepo/A"));
+	cl_must_pass(symlink_or_fake(repo, "..", "testrepo/A"));
 
 	cl_git_pass(git_checkout_tree(repo, obj, &checkout_opts));
 

tests/checkout/index.c

@@ -5,8 +5,10 @@
 #include "fileops.h"
 #include "repository.h"
 #include "remote.h"
+#include "repo/repo_helpers.h"
 
 static git_repository *g_repo;
+static git_buf g_global_path = GIT_BUF_INIT;
 
 void test_checkout_index__initialize(void)
 {
@@ -22,21 +24,29 @@ void test_checkout_index__initialize(void)
 	cl_git_rewritefile(
 		"./testrepo/.gitattributes",
 		"* text eol=lf\n");
+
+	git_libgit2_opts(GIT_OPT_GET_SEARCH_PATH, GIT_CONFIG_LEVEL_GLOBAL,
+		&g_global_path);
 }
 
 void test_checkout_index__cleanup(void)
 {
+	git_libgit2_opts(GIT_OPT_SET_SEARCH_PATH, GIT_CONFIG_LEVEL_GLOBAL,
+		g_global_path.ptr);
+	git_buf_dispose(&g_global_path);
+
 	cl_git_sandbox_cleanup();
 
-	/* try to remove alternative dir */
-	if (git_path_isdir("alternative"))
-		git_futils_rmdir_r("alternative", NULL, GIT_RMDIR_REMOVE_FILES);
+	/* try to remove directories created by tests */
+	cl_fixture_cleanup("alternative");
+	cl_fixture_cleanup("symlink");
+	cl_fixture_cleanup("symlink.git");
+	cl_fixture_cleanup("tmp_global_path");
 }
 
 void test_checkout_index__cannot_checkout_a_bare_repository(void)
 {
-	test_checkout_index__cleanup();
-
+	cl_git_sandbox_cleanup();
 	g_repo = cl_git_sandbox_init("testrepo.git");
 
 	cl_git_fail(git_checkout_index(g_repo, NULL, NULL));
@@ -136,23 +146,20 @@ void test_checkout_index__honor_coreautocrlf_setting_set_to_true(void)
 #endif
 }
 
-void test_checkout_index__honor_coresymlinks_default(void)
+static void populate_symlink_workdir(void)
 {
 	git_repository *repo;
 	git_remote *origin;
 	git_object *target;
-	char cwd[GIT_PATH_MAX];
 
 	const char *url = git_repository_path(g_repo);
 
-	cl_assert(getcwd(cwd, sizeof(cwd)) != NULL);
-	cl_assert_equal_i(0, p_mkdir("readonly", 0555)); /* Read-only directory */
-	cl_assert_equal_i(0, chdir("readonly"));
 	cl_git_pass(git_repository_init(&repo, "../symlink.git", true));
-	cl_assert_equal_i(0, chdir(cwd));
-	cl_assert_equal_i(0, p_mkdir("symlink", 0777));
 	cl_git_pass(git_repository_set_workdir(repo, "symlink", 1));
 
+	/* Delete the `origin` repo (if it exists) so we can recreate it. */
+	git_remote_delete(repo, GIT_REMOTE_ORIGIN);
+
 	cl_git_pass(git_remote_create(&origin, repo, GIT_REMOTE_ORIGIN, url));
 	cl_git_pass(git_remote_fetch(origin, NULL, NULL, NULL));
 	git_remote_free(origin);
@@ -161,28 +168,79 @@ void test_checkout_index__honor_coresymlinks_default(void)
 	cl_git_pass(git_reset(repo, target, GIT_RESET_HARD, NULL));
 	git_object_free(target);
 	git_repository_free(repo);
+}
+
+void test_checkout_index__honor_coresymlinks_default_true(void)
+{
+	char link_data[GIT_PATH_MAX];
+	int link_size = GIT_PATH_MAX;
+
+	cl_must_pass(p_mkdir("symlink", 0777));
+
+	if (!filesystem_supports_symlinks("symlink/test"))
+		cl_skip();
 
 #ifdef GIT_WIN32
+	/*
+	 * Windows explicitly requires the global configuration to have
+	 * core.symlinks=true in addition to actual filesystem support.
+	 */
+	create_tmp_global_config("tmp_global_path", "core.symlinks", "true");
+#endif
+
+	populate_symlink_workdir();
+
+	link_size = p_readlink("./symlink/link_to_new.txt", link_data, link_size);
+	cl_assert(link_size >= 0);
+
+	link_data[link_size] = '\0';
+	cl_assert_equal_i(link_size, strlen("new.txt"));
+	cl_assert_equal_s(link_data, "new.txt");
+	check_file_contents("./symlink/link_to_new.txt", "my new file\n");
+}
+
+void test_checkout_index__honor_coresymlinks_default_false(void)
+{
+	cl_must_pass(p_mkdir("symlink", 0777));
+
+#ifndef GIT_WIN32
+	/*
+	 * This test is largely for Windows platforms to ensure that
+	 * we respect an unset core.symlinks even when the platform
+	 * supports symlinks.  Bail entirely on POSIX platforms that
+	 * do support symlinks.
+	 */
+	if (filesystem_supports_symlinks("symlink/test"))
+		cl_skip();
+#endif
+
+	populate_symlink_workdir();
 	check_file_contents("./symlink/link_to_new.txt", "new.txt");
-#else
-	{
-		char link_data[1024];
-		size_t link_size = 1024;
-
-		link_size = p_readlink("./symlink/link_to_new.txt", link_data, link_size);
-		link_data[link_size] = '\0';
-		cl_assert_equal_i(link_size, strlen("new.txt"));
-		cl_assert_equal_s(link_data, "new.txt");
-		check_file_contents("./symlink/link_to_new.txt", "my new file\n");
+}
+
+void test_checkout_index__coresymlinks_set_to_true_fails_when_unsupported(void)
+{
+	git_checkout_options opts = GIT_CHECKOUT_OPTIONS_INIT;
+
+	if (filesystem_supports_symlinks("testrepo/test")) {
+		cl_skip();
 	}
-#endif
 
-	cl_fixture_cleanup("symlink");
+	cl_repo_set_bool(g_repo, "core.symlinks", true);
+
+	opts.checkout_strategy = GIT_CHECKOUT_SAFE | GIT_CHECKOUT_RECREATE_MISSING;
+	cl_git_fail(git_checkout_index(g_repo, NULL, &opts));
 }
 
 void test_checkout_index__honor_coresymlinks_setting_set_to_true(void)
 {
 	git_checkout_options opts = GIT_CHECKOUT_OPTIONS_INIT;
+	char link_data[GIT_PATH_MAX];
+	size_t link_size = GIT_PATH_MAX;
+
+	if (!filesystem_supports_symlinks("testrepo/test")) {
+		cl_skip();
+	}
 
 	cl_repo_set_bool(g_repo, "core.symlinks", true);
 
@@ -190,20 +248,11 @@ void test_checkout_index__honor_coresymlinks_setting_set_to_true(void)
 
 	cl_git_pass(git_checkout_index(g_repo, NULL, &opts));
 
-#ifdef GIT_WIN32
-	check_file_contents("./testrepo/link_to_new.txt", "new.txt");
-#else
-	{
-		char link_data[1024];
-		size_t link_size = 1024;
-
-		link_size = p_readlink("./testrepo/link_to_new.txt", link_data, link_size);
-		link_data[link_size] = '\0';
-		cl_assert_equal_i(link_size, strlen("new.txt"));
-		cl_assert_equal_s(link_data, "new.txt");
-		check_file_contents("./testrepo/link_to_new.txt", "my new file\n");
-	}
-#endif
+	link_size = p_readlink("./testrepo/link_to_new.txt", link_data, link_size);
+	link_data[link_size] = '\0';
+	cl_assert_equal_i(link_size, strlen("new.txt"));
+	cl_assert_equal_s(link_data, "new.txt");
+	check_file_contents("./testrepo/link_to_new.txt", "my new file\n");
 }
 
 void test_checkout_index__honor_coresymlinks_setting_set_to_false(void)
@@ -474,7 +523,7 @@ void test_checkout_index__can_overcome_name_clashes(void)
 	cl_assert(git_path_isfile("./testrepo/path0/file0"));
 
 	opts.checkout_strategy =
-		GIT_CHECKOUT_SAFE | 
+		GIT_CHECKOUT_SAFE |
 		GIT_CHECKOUT_RECREATE_MISSING |
 		GIT_CHECKOUT_ALLOW_CONFLICTS;
 	cl_git_pass(git_checkout_index(g_repo, index, &opts));
@@ -547,9 +596,9 @@ void test_checkout_index__can_update_prefixed_files(void)
 
 void test_checkout_index__can_checkout_a_newly_initialized_repository(void)
 {
-	test_checkout_index__cleanup();
-
+	cl_git_sandbox_cleanup();
 	g_repo = cl_git_sandbox_init("empty_standard_repo");
+
 	cl_git_remove_placeholders(git_repository_path(g_repo), "dummy-marker.txt");
 
 	cl_git_pass(git_checkout_index(g_repo, NULL, NULL));
@@ -559,8 +608,7 @@ void test_checkout_index__issue_1397(void)
 {
 	git_checkout_options opts = GIT_CHECKOUT_OPTIONS_INIT;
 
-	test_checkout_index__cleanup();
-
+	cl_git_sandbox_cleanup();
 	g_repo = cl_git_sandbox_init("issue_1397");
 
 	cl_repo_set_bool(g_repo, "core.autocrlf", true);
@@ -613,8 +661,7 @@ void test_checkout_index__target_directory_from_bare(void)
 	checkout_counts cts;
 	memset(&cts, 0, sizeof(cts));
 
-	test_checkout_index__cleanup();
-
+	cl_git_sandbox_cleanup();
 	g_repo = cl_git_sandbox_init("testrepo.git");
 	cl_assert(git_repository_is_bare(g_repo));
 

tests/repo/init.c

@@ -4,6 +4,7 @@
 #include "config.h"
 #include "path.h"
 #include "config/config_helpers.h"
+#include "repo/repo_helpers.h"
 
 enum repo_mode {
 	STANDARD_REPOSITORY = 0,
@@ -12,7 +13,6 @@ enum repo_mode {
 
 static git_repository *_repo = NULL;
 static git_buf _global_path = GIT_BUF_INIT;
-static git_buf _tmp_path = GIT_BUF_INIT;
 static mode_t g_umask = 0;
 
 void test_repo_init__initialize(void)
@@ -35,9 +35,7 @@ void test_repo_init__cleanup(void)
 		_global_path.ptr);
 	git_buf_dispose(&_global_path);
 
-	if (_tmp_path.size > 0 && git_path_isdir(_tmp_path.ptr))
-		git_futils_rmdir_r(_tmp_path.ptr, NULL, GIT_RMDIR_REMOVE_FILES);
-	git_buf_dispose(&_tmp_path);
+	cl_fixture_cleanup("tmp_global_path");
 }
 
 static void cleanup_repository(void *path)
@@ -247,6 +245,68 @@ void test_repo_init__detect_ignorecase(void)
 		"core.ignorecase", found_without_match ? true : GIT_ENOTFOUND);
 }
 
+/*
+ * Windows: if the filesystem supports symlinks (because we're running
+ * as administrator, or because the user has opted into it for normal
+ * users) then we can also opt-in explicitly by settings `core.symlinks`
+ * in the global config.  Symlinks remain off by default.
+ */
+
+void test_repo_init__symlinks_win32_enabled_by_global_config(void)
+{
+#ifndef GIT_WIN32
+	cl_skip();
+#else
+	git_config *config, *repo_config;
+	int val;
+
+	if (!filesystem_supports_symlinks("link"))
+		cl_skip();
+
+	create_tmp_global_config("tmp_global_config", "core.symlinks", "true");
+
+	/*
+	 * Create a new repository (can't use `assert_config_on_init` since we
+	 * want to examine configuration levels with more granularity.)
+	 */
+	cl_git_pass(git_repository_init(&_repo, "config_entry/test.non.bare.git", false));
+
+	/* Ensure that core.symlinks remains set (via the global config). */
+	cl_git_pass(git_repository_config(&config, _repo));
+	cl_git_pass(git_config_get_bool(&val, config, "core.symlinks"));
+	cl_assert_equal_i(1, val);
+
+	/*
+	 * Ensure that the repository config does not set core.symlinks.
+	 * It should remain inherited.
+	 */
+	cl_git_pass(git_config_open_level(&repo_config, config, GIT_CONFIG_LEVEL_LOCAL));
+	cl_git_fail_with(GIT_ENOTFOUND, git_config_get_bool(&val, repo_config, "core.symlinks"));
+	git_config_free(repo_config);
+
+	git_config_free(config);
+#endif
+}
+
+void test_repo_init__symlinks_win32_off_by_default(void)
+{
+#ifndef GIT_WIN32
+	cl_skip();
+#else
+	assert_config_entry_on_init("core.symlinks", false);
+#endif
+}
+
+void test_repo_init__symlinks_posix_detected(void)
+{
+#ifdef GIT_WIN32
+	cl_skip();
+#else
+	assert_config_entry_on_init(
+	    "core.symlinks", filesystem_supports_symlinks("link") ? GIT_ENOTFOUND : false);
+#endif
+}
+
 void test_repo_init__detect_precompose_unicode_required(void)
 {
 #ifdef GIT_USE_ICONV
@@ -563,26 +623,7 @@ static const char *template_sandbox(const char *name)
 
 static void configure_templatedir(const char *template_path)
 {
-	git_buf config_path = GIT_BUF_INIT;
-	git_buf config_data = GIT_BUF_INIT;
-
-    cl_git_pass(git_libgit2_opts(GIT_OPT_GET_SEARCH_PATH,
-		GIT_CONFIG_LEVEL_GLOBAL, &_tmp_path));
-	cl_git_pass(git_buf_puts(&_tmp_path, ".tmp"));
-	cl_git_pass(git_libgit2_opts(GIT_OPT_SET_SEARCH_PATH,
-		GIT_CONFIG_LEVEL_GLOBAL, _tmp_path.ptr));
-
-	cl_must_pass(p_mkdir(_tmp_path.ptr, 0777));
-
-	cl_git_pass(git_buf_joinpath(&config_path, _tmp_path.ptr, ".gitconfig"));
-
-	cl_git_pass(git_buf_printf(&config_data,
-		"[init]\n\ttemplatedir = \"%s\"\n", template_path));
-
-	cl_git_mkfile(config_path.ptr, config_data.ptr);
-
-	git_buf_dispose(&config_path);
-	git_buf_dispose(&config_data);
+	create_tmp_global_config("tmp_global_path", "init.templatedir", template_path);
 }
 
 static void validate_templates(git_repository *repo, const char *template_path)

tests/repo/repo_helpers.c

@@ -20,3 +20,33 @@ void delete_head(git_repository* repo)
 
 	git_buf_dispose(&head_path);
 }
+
+int filesystem_supports_symlinks(const char *path)
+{
+	struct stat st;
+	bool support = 0;
+
+	if (p_symlink("target", path) == 0) {
+		if (p_lstat(path, &st) == 0 && S_ISLNK(st.st_mode))
+			support = 1;
+
+		p_unlink(path);
+	}
+
+	return support;
+}
+
+void create_tmp_global_config(const char *dirname, const char *key, const char *val)
+{
+	git_buf path = GIT_BUF_INIT;
+	git_config *config;
+
+	cl_git_pass(git_libgit2_opts(GIT_OPT_SET_SEARCH_PATH,
+		GIT_CONFIG_LEVEL_GLOBAL, dirname));
+	cl_must_pass(p_mkdir(dirname, 0777));
+	cl_git_pass(git_buf_joinpath(&path, dirname, ".gitconfig"));
+	cl_git_pass(git_config_open_ondisk(&config, path.ptr));
+	cl_git_pass(git_config_set_string(config, key, val));
+	git_config_free(config);
+	git_buf_dispose(&path);
+}

tests/repo/repo_helpers.h

@@ -4,3 +4,5 @@
 
 extern void make_head_unborn(git_repository* repo, const char *target);
 extern void delete_head(git_repository* repo);
+extern int filesystem_supports_symlinks(const char *path);
+extern void create_tmp_global_config(const char *path, const char *key, const char *val);