Use git_buf for path storage instead of stack-based buffers

This converts virtually all of the places that allocate GIT_PATH_MAX
buffers on the stack for manipulating paths to use git_buf objects
instead.  The patch is pretty careful not to touch the public API
for libgit2, so there are a few places that still use GIT_PATH_MAX.

This extends and changes some details of the git_buf implementation
to add a couple of extra functions and to make error handling easier.

This includes serious alterations to all the path.c functions, and
several of the fileops.c ones, too.  Also, there are a number of new
functions that parallel existing ones except that use a git_buf
instead of a stack-based buffer (such as git_config_find_global_r
that exists alongsize git_config_find_global).

This also modifies the win32 version of p_realpath to allocate whatever
buffer size is needed to accommodate the realpath instead of hardcoding
a GIT_PATH_MAX limit, but that change needs to be tested still.

1 files changed, 1 insertions, 0 deletions

diff --git a/tests-clay/clay.h b/tests-clay/clay.h
index b3aae467c..608980d44 100644
--- a/tests-clay/clay.h
+++ b/tests-clay/clay.h
@@ -111,6 +111,7 @@ extern void test_core_path__1(void);
 extern void test_core_path__2(void);
 extern void test_core_path__5(void);
 extern void test_core_path__6(void);
+extern void test_core_path__7(void);
 extern void test_core_rmdir__delete_recursive(void);
 extern void test_core_rmdir__fail_to_delete_non_empty_dir(void);
 extern void test_core_rmdir__initialize(void);