Use the new git__joinpath to build paths in methods

The `git__joinpath` function has been changed to use a statically
allocated buffer; we assume the buffer to be 4096 bytes, because fuck
you.

The new method also supports an arbritrary number of paths to join,
which may come in handy in the future.

Some methods which were manually joining paths with `strcpy` now use the
new function, namely those in `index.c` and `refs.c`.

Based on Emeric Fermas' original patch, which was using the old
`git__joinpath` because I'm stupid. Thanks!

Signed-off-by: Vicent Marti <tanoku@gmail.com>

6 files changed, 59 insertions, 83 deletions

diff --git a/src/index.c b/src/index.c
index 6fdb46e18..0e77105b8 100644
--- a/src/index.c
+++ b/src/index.c
@@ -289,8 +289,7 @@ int git_index_add(git_index *index, const char *rel_path, int stage)
 	if (index->repository == NULL)
 		return GIT_EBAREINDEX;
 
-	strcpy(full_path, index->repository->path_workdir);
-	strcat(full_path, rel_path);
+	git__joinpath(full_path, index->repository->path_workdir, rel_path);
 
 	if (gitfo_exists(full_path) < 0)
 		return GIT_ENOTFOUND;
diff --git a/src/refs.c b/src/refs.c
index eca50ddaa..a3055650f 100644
--- a/src/refs.c
+++ b/src/refs.c
@@ -159,8 +159,7 @@ static int read_loose_ref(gitfo_buf *file_content, const char *name, const char
 	char ref_path[GIT_PATH_MAX];
 
 	/* Determine the full path of the ref */
-	strcpy(ref_path, repo_path);
-	strcat(ref_path, name);
+	git__joinpath(ref_path, repo_path, name);
 
 	/* Does it even exist ? */
 	if (gitfo_exists(ref_path) < GIT_SUCCESS)
@@ -228,8 +227,7 @@ static int read_packed_refs(gitfo_buf *packfile, const char *repo_path)
 	char ref_path[GIT_PATH_MAX];
 
 	/* Determine the full path of the file */
-	strcpy(ref_path, repo_path);
-	strcat(ref_path, GIT_PACKEDREFS_FILE);
+	git__joinpath(ref_path, repo_path, GIT_PACKEDREFS_FILE);
 
 	/* Does it even exist ? */
 	if (gitfo_exists(ref_path) < GIT_SUCCESS)
@@ -528,8 +526,7 @@ int git_reference_write(git_reference *ref)
 	if ((error = check_refname(ref->name)) < GIT_SUCCESS)
 		return error;
 
-	strcpy(ref_path, ref->owner->path_repository);
-	strcat(ref_path, ref->name);
+	git__joinpath(ref_path, ref->owner->path_repository, ref->name);
 
 	if ((error = git_filelock_init(&lock, ref_path)) < GIT_SUCCESS)
 		goto error_cleanup;
diff --git a/src/util.c b/src/util.c
index 67b74eeba..fc1682f90 100644
--- a/src/util.c
+++ b/src/util.c
@@ -202,30 +202,30 @@ const char *git__topdir(const char *path)
 	return &path[i + 1];
 }
 
-char *git__joinpath(const char *path_a, const char *path_b)
+void git__joinpath_n(char *buffer_out, int count, ...)
 {
-	int len_a, len_b;
-	char *path_new;
-
-	assert(path_a && path_b);
+	va_list ap;
+	int i;
 
-	len_a = strlen(path_a);
-	len_b = strlen(path_b);
+	va_start(ap, count);
+	for (i = 0; i < count; ++i) {
+		const char *path;
+		int len;
 
-	path_new = git__malloc(len_a + len_b + 2);
-	if (path_new == NULL)
-		return NULL;
+		path = va_arg(ap, const char *);
+		if (i > 0 && *path == '/')
+			path++;
 
-	strcpy(path_new, path_a);
+		len = strlen(path);
+		memcpy(buffer_out, path, len);
+		buffer_out = buffer_out + len;
 
-	if (len_a > 0 && len_b > 0 && path_new[len_a - 1] != '/')
-		path_new[len_a++] = '/';
-
-	if (path_b[0] == '/')
-		path_b++;
+		if (i < count - 1 && buffer_out[-1] != '/')
+			*buffer_out++ = '/';
+	}
+	va_end(ap);
 
-	strcpy(path_new + len_a, path_b);
-	return path_new;
+	*buffer_out = '\0';
 }
 
 static char *strtok_raw(char *output, char *src, char *delimit, int keep)
diff --git a/src/util.h b/src/util.h
index 0f010929f..d5320e15b 100644
--- a/src/util.h
+++ b/src/util.h
@@ -62,9 +62,15 @@ extern const char *git__topdir(const char *path);
  * Join two paths together. Takes care of properly fixing the
  * middle slashes and everything
  *
- * Returns a newly allocated string; must be free'd manually.
+ * The paths are joined together into buffer_out; this is expected
+ * to be an user allocated buffer of `GIT_PATH_MAX` size 
  */
-extern char *git__joinpath(const char *path_a, const char *path_b);
+extern void git__joinpath_n(char *buffer_out, int npath, ...);
+
+GIT_INLINE(void) git__joinpath(char *buffer_out, const char *path_a, const char *path_b)
+{
+	git__joinpath_n(buffer_out, 2, path_a, path_b);
+}
 
 extern void git__hexdump(const char *buffer, size_t n);
 extern uint32_t git__hash(const void *key, int len, uint32_t seed);
@@ -84,18 +90,6 @@ GIT_INLINE(int) git__is_sizet(git_off_t p)
 #	define git__rotl(v, s) (uint32_t)(((uint32_t)(v) << (s)) | ((uint32_t)(v) >> (32 - (s))))
 #endif
 
-enum git_splitpath_flags
-{
-   GIT_SPL_PATH = 1,
-   GIT_SPL_FILE = 2,
-   GIT_SPL_EXT  = 4,
-   GIT_SPL_PATH_FILE = GIT_SPL_PATH + GIT_SPL_FILE,
-   GIT_SPL_FILE_EXT  = GIT_SPL_FILE + GIT_SPL_EXT,
-   GIT_SPL_EXT_NO_PERIOD = 8,
-};
-
-
-extern char *git__splitpath(char *path, int flag);
 extern char *git__strtok(char *output, char *src, char *delimit);
 extern char *git__strtok_keep(char *output, char *src, char *delimit);
 
diff --git a/tests/t00-core.c b/tests/t00-core.c
index f20aa9d76..96bf3e772 100644
--- a/tests/t00-core.c
+++ b/tests/t00-core.c
@@ -344,25 +344,15 @@ END_TEST
 
 static int ensure_joinpath(const char *path_a, const char *path_b, const char *expected_path)
 {
-	int error = GIT_SUCCESS;
-	char* joined_path;
-
-	joined_path = git__joinpath(path_a, path_b);
-	if (joined_path == NULL)
-		return GIT_ERROR;
-
-	if (strcmp(joined_path, expected_path))
-		error = GIT_ERROR;
-
-	free(joined_path);
-
-	return error;
+	char joined_path[GIT_PATH_MAX];
+	git__joinpath(joined_path, path_a, path_b);
+	return strcmp(joined_path, expected_path) == 0 ? GIT_SUCCESS : GIT_ERROR;
 }
 
 BEGIN_TEST("path", joinpath)
-	must_pass(ensure_joinpath("", "", ""));
-	must_pass(ensure_joinpath("", "a", "a"));
-	must_pass(ensure_joinpath("a", "", "a"));
+	must_pass(ensure_joinpath("", "", "/"));
+	must_pass(ensure_joinpath("", "a", "/a"));
+	must_pass(ensure_joinpath("a", "", "a/"));
 	must_pass(ensure_joinpath("a", "b", "a/b"));
 	must_pass(ensure_joinpath("/", "a", "/a"));
 	must_pass(ensure_joinpath("/", "", "/"));
diff --git a/tests/t10-refs.c b/tests/t10-refs.c
index 222f09997..2d055c978 100644
--- a/tests/t10-refs.c
+++ b/tests/t10-refs.c
@@ -192,7 +192,7 @@ BEGIN_TEST("createref", create_new_symbolic_ref)
 	git_reference *new_reference, *looked_up_ref, *resolved_ref;
 	git_repository *repo;
 	git_oid id;
-	char *ref_path;
+	char ref_path[GIT_PATH_MAX];
 
 	const char *new_head_tracker = "another-head-tracker";
 
@@ -201,8 +201,7 @@ BEGIN_TEST("createref", create_new_symbolic_ref)
 	must_pass(git_repository_open(&repo, REPOSITORY_FOLDER));
 
 	/* Retrieve the physical path to the symbolic ref for further cleaning */
-	ref_path = git__joinpath(repo->path_repository, new_head_tracker);
-	must_be_true(ref_path != NULL);
+	git__joinpath(ref_path, repo->path_repository, new_head_tracker);
 
 	/* Create and write the new symbolic reference */
 	must_pass(git_reference_new(&new_reference, repo));
@@ -211,16 +210,16 @@ BEGIN_TEST("createref", create_new_symbolic_ref)
 	must_pass(git_reference_write(new_reference));
 
 	/* Ensure the reference can be looked-up... */
-	must_pass(git_repository_lookup_ref(&looked_up_ref, repo, new_head_tracker));

-	must_be_true(looked_up_ref->type == GIT_REF_SYMBOLIC);

-	must_be_true(looked_up_ref->packed == 0);

-	must_be_true(strcmp(looked_up_ref->name, new_head_tracker) == 0);

-

-	/* ...peeled.. */

-	must_pass(git_reference_resolve(&resolved_ref, looked_up_ref));

-	must_be_true(resolved_ref->type == GIT_REF_OID);

-

-	/* ...and that it points to the current master tip */

+	must_pass(git_repository_lookup_ref(&looked_up_ref, repo, new_head_tracker));
+	must_be_true(looked_up_ref->type == GIT_REF_SYMBOLIC);
+	must_be_true(looked_up_ref->packed == 0);
+	must_be_true(strcmp(looked_up_ref->name, new_head_tracker) == 0);
+
+	/* ...peeled.. */
+	must_pass(git_reference_resolve(&resolved_ref, looked_up_ref));
+	must_be_true(resolved_ref->type == GIT_REF_OID);
+
+	/* ...and that it points to the current master tip */
 	must_be_true(git_oid_cmp(&id, git_reference_oid(resolved_ref)) == 0);
 
 	git_repository_free(repo);
@@ -228,21 +227,20 @@ BEGIN_TEST("createref", create_new_symbolic_ref)
 	/* Similar test with a fresh new repository */
 	must_pass(git_repository_open(&repo, REPOSITORY_FOLDER));
 
-	must_pass(git_repository_lookup_ref(&looked_up_ref, repo, new_head_tracker));

-	must_pass(git_reference_resolve(&resolved_ref, looked_up_ref));

+	must_pass(git_repository_lookup_ref(&looked_up_ref, repo, new_head_tracker));
+	must_pass(git_reference_resolve(&resolved_ref, looked_up_ref));
 	must_be_true(git_oid_cmp(&id, git_reference_oid(resolved_ref)) == 0);
 
 	git_repository_free(repo);
 
 	must_pass(gitfo_unlink(ref_path));	/* TODO: replace with git_reference_delete() when available */
-	free(ref_path);
 END_TEST
 
 BEGIN_TEST("createref", create_new_object_id_ref)
 	git_reference *new_reference, *looked_up_ref;
 	git_repository *repo;
 	git_oid id;
-	char *ref_path;
+	char ref_path[GIT_PATH_MAX];
 
 	const char *new_head = "refs/heads/new-head";
 
@@ -251,8 +249,7 @@ BEGIN_TEST("createref", create_new_object_id_ref)
 	must_pass(git_repository_open(&repo, REPOSITORY_FOLDER));
 
 	/* Retrieve the physical path to the symbolic ref for further cleaning */
-	ref_path = git__joinpath(repo->path_repository, new_head);
-	must_be_true(ref_path != NULL);
+	git__joinpath(ref_path, repo->path_repository, new_head);
 
 	/* Create and write the new object id reference */
 	must_pass(git_reference_new(&new_reference, repo));
@@ -261,12 +258,12 @@ BEGIN_TEST("createref", create_new_object_id_ref)
 	must_pass(git_reference_write(new_reference));
 
 	/* Ensure the reference can be looked-up... */
-	must_pass(git_repository_lookup_ref(&looked_up_ref, repo, new_head));

-	must_be_true(looked_up_ref->type == GIT_REF_OID);

-	must_be_true(looked_up_ref->packed == 0);

-	must_be_true(strcmp(looked_up_ref->name, new_head) == 0);

-

-	/* ...and that it points to the current master tip */

+	must_pass(git_repository_lookup_ref(&looked_up_ref, repo, new_head));
+	must_be_true(looked_up_ref->type == GIT_REF_OID);
+	must_be_true(looked_up_ref->packed == 0);
+	must_be_true(strcmp(looked_up_ref->name, new_head) == 0);
+
+	/* ...and that it points to the current master tip */
 	must_be_true(git_oid_cmp(&id, git_reference_oid(looked_up_ref)) == 0);
 
 	git_repository_free(repo);
@@ -274,13 +271,12 @@ BEGIN_TEST("createref", create_new_object_id_ref)
 	/* Similar test with a fresh new repository */
 	must_pass(git_repository_open(&repo, REPOSITORY_FOLDER));
 
-	must_pass(git_repository_lookup_ref(&looked_up_ref, repo, new_head));

+	must_pass(git_repository_lookup_ref(&looked_up_ref, repo, new_head));
 	must_be_true(git_oid_cmp(&id, git_reference_oid(looked_up_ref)) == 0);
 
 	git_repository_free(repo);
 
 	must_pass(gitfo_unlink(ref_path));	/* TODO: replace with git_reference_delete() when available */
-	free(ref_path);
 END_TEST
 
 git_testsuite *libgit2_suite_refs(void)