thodg/libgit2

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 62ebbf4..c741499 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -27,9 +27,14 @@ OPTION( BUILD_EXAMPLES		"Build library usage example apps"		OFF )
 OPTION( TAGS				"Generate tags"							OFF )
 OPTION( PROFILE				"Generate profiling information"		OFF )
 OPTION( ENABLE_TRACE		"Enables tracing support"				OFF )
-OPTION( LIBGIT2_FILENAME	"Name of the produced binary" OFF )
+OPTION( LIBGIT2_FILENAME	"Name of the produced binary"			OFF )
 
-OPTION( ANDROID				"Build for android NDK" OFF )
+OPTION( ANDROID				"Build for android NDK"	 				OFF )
+
+OPTION( USE_ICONV			"Link with and use iconv library" 		OFF )
+IF(APPLE)
+	SET( USE_ICONV ON )
+ENDIF()
 
 IF(MSVC)
 	# This option is only available when building with MSVC. By default, libgit2
@@ -58,8 +63,11 @@ FUNCTION(TARGET_OS_LIBRARIES target)
 		TARGET_LINK_LIBRARIES(${target} socket nsl)
 	ELSEIF(CMAKE_SYSTEM_NAME MATCHES "Linux")
 		TARGET_LINK_LIBRARIES(${target} rt)
-	ELSEIF(APPLE)
+	ENDIF()
+
+	IF(USE_ICONV)
 		TARGET_LINK_LIBRARIES(${target} iconv)
+		ADD_DEFINITIONS(-DGIT_USE_ICONV)
 	ENDIF()
 
 	IF(THREADSAFE)
diff --git a/include/git2/refs.h b/include/git2/refs.h
index 4871e98..4041947 100644
--- a/include/git2/refs.h
+++ b/include/git2/refs.h
@@ -453,7 +453,7 @@ GIT_EXTERN(int) git_reference_is_remote(git_reference *ref);
 GIT_EXTERN(int) git_reference_is_tag(git_reference *ref);
 
 typedef enum {
-	GIT_REF_FORMAT_NORMAL = 0,
+	GIT_REF_FORMAT_NORMAL = 0u,
 
 	/**
 	 * Control whether one-level refnames are accepted
@@ -461,7 +461,7 @@ typedef enum {
 	 * components). Those are expected to be written only using
 	 * uppercase letters and underscore (FETCH_HEAD, ...)
 	 */
-	GIT_REF_FORMAT_ALLOW_ONELEVEL = (1 << 0),
+	GIT_REF_FORMAT_ALLOW_ONELEVEL = (1u << 0),
 
 	/**
 	 * Interpret the provided name as a reference pattern for a
@@ -470,14 +470,14 @@ typedef enum {
 	 * in place of a one full pathname component
 	 * (e.g., foo/<star>/bar but not foo/bar<star>).
 	 */
-	GIT_REF_FORMAT_REFSPEC_PATTERN = (1 << 1),
+	GIT_REF_FORMAT_REFSPEC_PATTERN = (1u << 1),
 
 	/**
 	 * Interpret the name as part of a refspec in shorthand form
 	 * so the `ONELEVEL` naming rules aren't enforced and 'master'
 	 * becomes a valid name.
 	 */
-	GIT_REF_FORMAT_REFSPEC_SHORTHAND = (1 << 2),
+	GIT_REF_FORMAT_REFSPEC_SHORTHAND = (1u << 2),
 } git_reference_normalize_t;
 
 /**
diff --git a/include/git2/repository.h b/include/git2/repository.h
index 28d8400..b4d5619 100644
--- a/include/git2/repository.h
+++ b/include/git2/repository.h
@@ -288,25 +288,6 @@ GIT_EXTERN(int) git_repository_init_ext(
 	git_repository_init_options *opts);
 
 /**
- * Update the filesystem config settings for an open repository
- *
- * When a repository is initialized, config values are set based on the
- * properties of the filesystem that the repository is on, such as
- * "core.ignorecase", "core.filemode", "core.symlinks", etc.  If the
- * repository is moved to a new filesystem, these properties may no
- * longer be correct and API calls may not behave as expected.  This
- * call reruns the phase of repository initialization that sets those
- * properties to compensate for the current filesystem of the repo.
- *
- * @param repo A repository object
- * @param recurse_submodules Should submodules be reset recursively
- * @returrn 0 on success, < 0 on error
- */
-GIT_EXTERN(int) git_repository_reset_filesystem(
-	git_repository *repo,
-	int recurse_submodules);
-
-/**
  * Retrieve and resolve the reference pointed at by HEAD.
  *
  * The returned `git_reference` will be owned by caller and
diff --git a/include/git2/sys/repository.h b/include/git2/sys/repository.h
index ba3d65a..e77b1dc 100644
--- a/include/git2/sys/repository.h
+++ b/include/git2/sys/repository.h
@@ -27,7 +27,6 @@ GIT_BEGIN_DECL
  */
 GIT_EXTERN(int) git_repository_new(git_repository **out);
 
-
 /**
  * Reset all the internal state in a repository.
  *
@@ -42,6 +41,25 @@ GIT_EXTERN(int) git_repository_new(git_repository **out);
 GIT_EXTERN(void) git_repository__cleanup(git_repository *repo);
 
 /**
+ * Update the filesystem config settings for an open repository
+ *
+ * When a repository is initialized, config values are set based on the
+ * properties of the filesystem that the repository is on, such as
+ * "core.ignorecase", "core.filemode", "core.symlinks", etc.  If the
+ * repository is moved to a new filesystem, these properties may no
+ * longer be correct and API calls may not behave as expected.  This
+ * call reruns the phase of repository initialization that sets those
+ * properties to compensate for the current filesystem of the repo.
+ *
+ * @param repo A repository object
+ * @param recurse_submodules Should submodules be reset recursively
+ * @returrn 0 on success, < 0 on error
+ */
+GIT_EXTERN(int) git_repository_reset_filesystem(
+	git_repository *repo,
+	int recurse_submodules);
+
+/**
  * Set the configuration file for this repository
  *
  * This configuration file will be used for all configuration
diff --git a/src/path.h b/src/path.h
index 1757569..eaf94d4 100644
--- a/src/path.h
+++ b/src/path.h
@@ -365,11 +365,6 @@ extern int git_path_set_error(
 /* check if non-ascii characters are present in filename */
 extern bool git_path_has_non_ascii(const char *path, size_t pathlen);
 
-/* only enable iconv on Mac for now */
-#ifdef __APPLE__
-#define GIT_USE_ICONV 1
-#endif
-
 #define GIT_PATH_REPO_ENCODING "UTF-8"
 
 #ifdef __APPLE__
diff --git a/src/refs.c b/src/refs.c
index c045ab9..0da02a6 100644
--- a/src/refs.c
+++ b/src/refs.c
@@ -138,6 +138,22 @@ int git_reference_name_to_id(
 	return 0;
 }
 
+static int reference_normalize_for_repo(
+	char *out,
+	size_t out_size,
+	git_repository *repo,
+	const char *name)
+{
+	int precompose;
+	unsigned int flags = GIT_REF_FORMAT_ALLOW_ONELEVEL;
+
+	if (!git_repository__cvar(&precompose, repo, GIT_CVAR_PRECOMPOSE) &&
+		precompose)
+		flags |= GIT_REF_FORMAT__PRECOMPOSE_UNICODE;
+
+	return git_reference_normalize_name(out, out_size, name, flags);
+}
+
 int git_reference_lookup_resolved(
 	git_reference **ref_out,
 	git_repository *repo,
@@ -159,13 +175,13 @@ int git_reference_lookup_resolved(
 	else if (max_nesting < 0)
 		max_nesting = DEFAULT_NESTING_LEVEL;
 
-	strncpy(scan_name, name, GIT_REFNAME_MAX);
 	scan_type = GIT_REF_SYMBOLIC;
 
-	if ((error = git_repository_refdb__weakptr(&refdb, repo)) < 0)
-		return -1;
+	if ((error = reference_normalize_for_repo(
+			scan_name, sizeof(scan_name), repo, name)) < 0)
+		return error;
 
-	if ((error = git_reference__normalize_name_lax(scan_name, GIT_REFNAME_MAX, name)) < 0)
+	if ((error = git_repository_refdb__weakptr(&refdb, repo)) < 0)
 		return error;
 
 	for (nesting = max_nesting;
@@ -173,7 +189,7 @@ int git_reference_lookup_resolved(
 		 nesting--)
 	{
 		if (nesting != max_nesting) {
-			strncpy(scan_name, ref->target.symbolic, GIT_REFNAME_MAX);
+			strncpy(scan_name, ref->target.symbolic, sizeof(scan_name));
 			git_reference_free(ref);
 		}
 
@@ -711,17 +727,18 @@ static bool is_all_caps_and_underscore(const char *name, size_t len)
 	return true;
 }
 
+/* Inspired from https://github.com/git/git/blob/f06d47e7e0d9db709ee204ed13a8a7486149f494/refs.c#L36-100 */
 int git_reference__normalize_name(
 	git_buf *buf,
 	const char *name,
 	unsigned int flags)
 {
-	// Inspired from https://github.com/git/git/blob/f06d47e7e0d9db709ee204ed13a8a7486149f494/refs.c#L36-100
-
 	char *current;
 	int segment_len, segments_count = 0, error = GIT_EINVALIDSPEC;
 	unsigned int process_flags;
 	bool normalize = (buf != NULL);
+	git_path_iconv_t ic = GIT_PATH_ICONV_INIT;
+
 	assert(name);
 
 	process_flags = flags;
@@ -733,6 +750,13 @@ int git_reference__normalize_name(
 	if (normalize)
 		git_buf_clear(buf);
 
+	if ((flags & GIT_REF_FORMAT__PRECOMPOSE_UNICODE) != 0) {
+		size_t namelen = strlen(current);
+		if ((error = git_path_iconv_init_precompose(&ic)) < 0 ||
+			(error = git_path_iconv(&ic, &current, &namelen)) < 0)
+			goto cleanup;
+	}
+
 	while (true) {
 		segment_len = ensure_segment_validity(current);
 		if (segment_len < 0) {
@@ -809,6 +833,8 @@ cleanup:
 	if (error && normalize)
 		git_buf_free(buf);
 
+	git_path_iconv_clear(&ic);
+
 	return error;
 }
 
@@ -983,9 +1009,9 @@ static int peel_error(int error, git_reference *ref, const char* msg)
 }
 
 int git_reference_peel(
-		git_object **peeled,
-		git_reference *ref,
-		git_otype target_type)
+	git_object **peeled,
+	git_reference *ref,
+	git_otype target_type)
 {
 	git_reference *resolved = NULL;
 	git_object *target = NULL;
@@ -1027,24 +1053,19 @@ cleanup:
 	return error;
 }
 
-int git_reference__is_valid_name(
-	const char *refname,
-	unsigned int flags)
+int git_reference__is_valid_name(const char *refname, unsigned int flags)
 {
-	int error;
-
-	error = git_reference__normalize_name(NULL, refname, flags) == 0;
-	giterr_clear();
+	if (git_reference__normalize_name(NULL, refname, flags) < 0) {
+		giterr_clear();
+		return false;
+	}
 
-	return error;
+	return true;
 }
 
-int git_reference_is_valid_name(
-	const char *refname)
+int git_reference_is_valid_name(const char *refname)
 {
-	return git_reference__is_valid_name(
-		refname,
-		GIT_REF_FORMAT_ALLOW_ONELEVEL);
+	return git_reference__is_valid_name(refname, GIT_REF_FORMAT_ALLOW_ONELEVEL);
 }
 
 const char *git_reference_shorthand(git_reference *ref)
diff --git a/src/refs.h b/src/refs.h
index 4b91c25..80c7703 100644
--- a/src/refs.h
+++ b/src/refs.h
@@ -46,6 +46,8 @@
 #define GIT_STASH_FILE "stash"
 #define GIT_REFS_STASH_FILE GIT_REFS_DIR GIT_STASH_FILE
 
+#define GIT_REF_FORMAT__PRECOMPOSE_UNICODE	(1u << 16)
+
 #define GIT_REFNAME_MAX 1024
 
 struct git_reference {
diff --git a/tests-clar/clar_libgit2.c b/tests-clar/clar_libgit2.c
index 82ec5c0..9f65953 100644
--- a/tests-clar/clar_libgit2.c
+++ b/tests-clar/clar_libgit2.c
@@ -1,6 +1,7 @@
 #include "clar_libgit2.h"
 #include "posix.h"
 #include "path.h"
+#include "git2/sys/repository.h"
 
 void cl_git_report_failure(
 	int error, const char *file, int line, const char *fncall)
diff --git a/tests-clar/refs/unicode.c b/tests-clar/refs/unicode.c
index b29c63e..b560128 100644
--- a/tests-clar/refs/unicode.c
+++ b/tests-clar/refs/unicode.c
@@ -4,17 +4,13 @@ static git_repository *repo;
 
 void test_refs_unicode__initialize(void)
 {
-	cl_fixture_sandbox("testrepo.git");
-
-	cl_git_pass(git_repository_open(&repo, "testrepo.git"));
+	repo = cl_git_sandbox_init("testrepo.git");
 }
 
 void test_refs_unicode__cleanup(void)
 {
-	git_repository_free(repo);
+	cl_git_sandbox_cleanup();
 	repo = NULL;
-
-	cl_fixture_cleanup("testrepo.git");
 }
 
 void test_refs_unicode__create_and_lookup(void)
@@ -23,13 +19,12 @@ void test_refs_unicode__create_and_lookup(void)
 	git_repository *repo2;
 
 	const char *REFNAME = "refs/heads/" "\303\205" "ngstr" "\303\266" "m";
-	const char *REFNAME_DECOMPOSED =
-		"refs/heads/" "A" "\314\212" "ngstro" "\314\210" "m";
 	const char *master = "refs/heads/master";
 
 	/* Create the reference */
 	cl_git_pass(git_reference_lookup(&ref0, repo, master));
-	cl_git_pass(git_reference_create(&ref1, repo, REFNAME, git_reference_target(ref0), 0));
+	cl_git_pass(git_reference_create(
+		&ref1, repo, REFNAME, git_reference_target(ref0), 0));
 	cl_assert_equal_s(REFNAME, git_reference_name(ref1));
 	git_reference_free(ref0);
 
@@ -45,6 +40,8 @@ void test_refs_unicode__create_and_lookup(void)
 #if GIT_USE_ICONV
 	/* Lookup reference by decomposed unicode name */
 
+#define REFNAME_DECOMPOSED "refs/heads/" "A" "\314\212" "ngstro" "\314\210" "m"
+
 	cl_git_pass(git_reference_lookup(&ref2, repo2, REFNAME_DECOMPOSED));
 	cl_assert_equal_i(
 		0, git_oid_cmp(git_reference_target(ref1), git_reference_target(ref2)));