str: introduce `git_str` for internal, `git_buf` is externalethomson/gitstr

libgit2 has two distinct requirements that were previously solved by
`git_buf`.  We require:

1. A general purpose string class that provides a number of utility APIs
   for manipulating data (eg, concatenating, truncating, etc).
2. A structure that we can use to return strings to callers that they
   can take ownership of.

By using a single class (`git_buf`) for both of these purposes, we have
confused the API to the point that refactorings are difficult and
reasoning about correctness is also difficult.

Move the utility class `git_buf` to be called `git_str`: this represents
its general purpose, as an internal string buffer class.  The name also
is an homage to Junio Hamano ("gitstr").

The public API remains `git_buf`, and has a much smaller footprint.  It
is generally only used as an "out" param with strict requirements that
follow the documentation.  (Exceptions exist for some legacy APIs to
avoid breaking callers unnecessarily.)

Utility functions exist to convert a user-specified `git_buf` to a
`git_str` so that we can call internal functions, then converting it
back again.

1 files changed, 9 insertions, 9 deletions

diff --git a/src/sysdir.h b/src/sysdir.h
index cc5599e38..d12bac9d9 100644
--- a/src/sysdir.h
+++ b/src/sysdir.h
@@ -10,7 +10,7 @@
 #include "common.h"
 
 #include "posix.h"
-#include "buffer.h"
+#include "str.h"
 
 /**
  * Find a "global" file (i.e. one in a user's home directory).
@@ -19,7 +19,7 @@
  * @param filename name of file to find in the home directory
  * @return 0 if found, GIT_ENOTFOUND if not found, or -1 on other OS error
  */
-extern int git_sysdir_find_global_file(git_buf *path, const char *filename);
+extern int git_sysdir_find_global_file(git_str *path, const char *filename);
 
 /**
  * Find an "XDG" file (i.e. one in user's XDG config path).
@@ -28,7 +28,7 @@ extern int git_sysdir_find_global_file(git_buf *path, const char *filename);
  * @param filename name of file to find in the home directory
  * @return 0 if found, GIT_ENOTFOUND if not found, or -1 on other OS error
  */
-extern int git_sysdir_find_xdg_file(git_buf *path, const char *filename);
+extern int git_sysdir_find_xdg_file(git_str *path, const char *filename);
 
 /**
  * Find a "system" file (i.e. one shared for all users of the system).
@@ -37,7 +37,7 @@ extern int git_sysdir_find_xdg_file(git_buf *path, const char *filename);
  * @param filename name of file to find in the home directory
  * @return 0 if found, GIT_ENOTFOUND if not found, or -1 on other OS error
  */
-extern int git_sysdir_find_system_file(git_buf *path, const char *filename);
+extern int git_sysdir_find_system_file(git_str *path, const char *filename);
 
 /**
  * Find a "ProgramData" file (i.e. one in %PROGRAMDATA%)
@@ -46,7 +46,7 @@ extern int git_sysdir_find_system_file(git_buf *path, const char *filename);
  * @param filename name of file to find in the ProgramData directory
  * @return 0 if found, GIT_ENOTFOUND if not found, or -1 on other OS error
  */
-extern int git_sysdir_find_programdata_file(git_buf *path, const char *filename);
+extern int git_sysdir_find_programdata_file(git_str *path, const char *filename);
 
 /**
  * Find template directory.
@@ -54,7 +54,7 @@ extern int git_sysdir_find_programdata_file(git_buf *path, const char *filename)
  * @param path buffer to write the full path into
  * @return 0 if found, GIT_ENOTFOUND if not found, or -1 on other OS error
  */
-extern int git_sysdir_find_template_dir(git_buf *path);
+extern int git_sysdir_find_template_dir(git_str *path);
 
 /**
  * Expand the name of a "global" file (i.e. one in a user's home
@@ -66,7 +66,7 @@ extern int git_sysdir_find_template_dir(git_buf *path);
  * @param filename name of file in the home directory
  * @return 0 on success or -1 on error
  */
-extern int git_sysdir_expand_global_file(git_buf *path, const char *filename);
+extern int git_sysdir_expand_global_file(git_str *path, const char *filename);
 
 typedef enum {
 	GIT_SYSDIR_SYSTEM = 0,
@@ -87,11 +87,11 @@ extern int git_sysdir_global_init(void);
 /**
  * Get the search path for global/system/xdg files
  *
- * @param out pointer to git_buf containing search path
+ * @param out pointer to git_str containing search path
  * @param which which list of paths to return
  * @return 0 on success, <0 on failure
  */
-extern int git_sysdir_get(const git_buf **out, git_sysdir_t which);
+extern int git_sysdir_get(const git_str **out, git_sysdir_t which);
 
 /**
  * Set search paths for global/system/xdg files