Currently, the odb cache has a fixed size of 128 slots as defined by
GIT_DEFAULT_CACHE_SIZE. Allow users to set the size of the cache via
git_libgit2_opts().
Fixes#1035.
This switches the APIs for setting and getting the global/system
search paths from using git_strarray to using a simple string with
GIT_PATH_LIST_SEPARATOR delimited paths, just as the environment
PATH variable would contain. This makes it simpler to get and set
the value.
I also added code to expand "$PATH" when setting a new value to
embed the old value of the path. This means that I no longer
require separate actions to PREPEND to the value.
The goal of this work is to expose the search logic for "global",
"system", and "xdg" files through the git_libgit2_opts() interface.
Behind the scenes, I changed the logic for finding files to have a
notion of a git_strarray that represents a search path and to store
a separate search path for each of the three tiers of config file.
For each tier, I implemented a function to initialize it to default
values (generally based on environment variables), and then general
interfaces to get it, set it, reset it, and prepend new directories
to it.
Next, I exposed these interfaces through the git_libgit2_opts
interface, reusing the GIT_CONFIG_LEVEL_SYSTEM, etc., constants
for the user to control which search path they were modifying.
There are alternative designs for the opts interface / argument
ordering, so I'm putting this phase out for discussion.
Additionally, I ended up doing a little bit of clean up regarding
attr.h and attr_file.h, adding a new attrcache.h so the other two
files wouldn't have to be included in so many places.
Building a "shared object" (DLL) in Windows includes 2 steps:
- specify __declspec(dllexport)
when building the library itself. MSVC will disallow itself from
optimizing these symbols out and reference them in the PE's
Exports-Table.
Further, a static link library will be generated. This library
contains the symbols which are exported via the declsepc above.
The __declspec(dllexport) becomes part of the symbol-signature
(like parameter types in C++ are 'mangled' into the symbol name,
the export specifier is mingled with the name)
- specify __declspec(dllimport)
when using the library. This again mingles the declspec into the
name and declares the function / variable with external linkage.
cmake automatically adds -Dgit2_EXPORTS to the compiler arguments
when compiling the libgit2 project.
The 'git2' is the name specified via PROJECT() in CMakeLists.txt.
This adds preliminary support for pathspecs to diff and status.
The implementation is not very optimized (it still looks at
every single file and evaluated the the pathspec match against
them), but it works.
See `global.c` for a description of what we're doing.
When libgit2 is built with GIT_THREADS support, the threading system
must be explicitly initialized with `git_threads_init()`.
There were quite a few places were spaces were being used instead of
tabs. Try to catch them all. This should hopefully not break anything.
Except for `git blame`. Oh well.
1. The license header is technically not valid if it doesn't have a
copyright signature.
2. The COPYING file has been updated with the different licenses used in
the project.
3. The full GPLv2 header in each file annoys me.
The GIT_EXPORT macro is used to declare a function to be externally
accessible to other libraries. This commit uses GIT_EXPORT to declare
the git_lasterror() function as externally exported. I verified with
depends.exe that the function is available to external callers (i.e.
in the exports table of the PE file).
Ok, this is the real deal. Hopefully. Here's how it's going to work:
- One main method, called `git__throw`, that sets the error
code and error message when an error happens.
This method must be called in every single place where an error
code was being returned previously, setting an error message
instead.
Example, instead of:
return GIT_EOBJCORRUPTED;
Use:
return git__throw(GIT_EOBJCORRUPTED,
"The object is missing a finalizing line feed");
And instead of:
[...] {
error = GIT_EOBJCORRUPTED;
goto cleanup;
}
Use:
[...] {
error = git__throw(GIT_EOBJCORRUPTED, "What an error!");
goto cleanup;
}
The **only** exception to this are the allocation methods, which
return NULL on failure but already set the message manually.
/* only place where an error code can be returned directly,
because the error message has already been set by the wrapper */
if (foo == NULL)
return GIT_ENOMEM;
- One secondary method, called `git__rethrow`, which can be used to
fine-grain an error message and build an error stack.
Example, instead of:
if ((error = foobar(baz)) < GIT_SUCCESS)
return error;
You can now do:
if ((error = foobar(baz)) < GIT_SUCCESS)
return git__rethrow(error, "Failed to do a major operation");
The return of the `git_lasterror` method will be a string in the
shape of:
"Failed to do a major operation. (Failed to do an internal
operation)"
E.g.
"Failed to open the index. (Not enough permissions to access
'/path/to/index')."
NOTE: do not abuse this method. Try to write all `git__throw`
messages in a descriptive manner, to avoid having to rethrow them to
clarify their meaning.
This method should only be used in the places where the original
error message set by a subroutine is not specific enough.
It is encouraged to continue using this style as much possible to
enforce error propagation:
if ((error = foobar(baz)) < GIT_SUCCESS)
return error; /* `foobar` has set an error message, and
we are just propagating it */
The error handling revamp will take place in two phases:
- Phase 1: Replace all pieces of code that return direct error codes
with calls to `git__throw`. This can be done semi-automatically
using `ack` to locate all the error codes that must be replaced.
- Phase 2: Add some `git__rethrow` calls in those cases where the
original error messages are not specific enough.
Phase 1 is the main goal. A minor libgit2 release will be shipped once
Phase 1 is ready, and the work will start on gradually improving the
error handling mechanism by refining specific error messages.
OTHER NOTES:
- When writing error messages, please refrain from using weasel
words. They add verbosity to the message without giving any real
information. (<3 Emeric)
E.g.
"The reference file appears to be missing a carriage return"
Nope.
"The reference file is missing a carriage return"
Yes.
- When calling `git__throw`, please try to use more generic error
codes so we can eventually reduce the list of error codes to
something more reasonable. Feel free to add new, more generic error
codes if these are going to replace several of the old ones.
E.g.
return GIT_EREFCORRUPTED;
Can be turned into:
return git__throw(GIT_EOBJCORRUPTED,
"The reference is corrupted");
Hey. Apologies in advance -- I broke your bindings.
This is a major commit that includes a long-overdue redesign of the
whole object-database structure. This is expected to be the last major
external API redesign of the library until the first non-alpha release.
Please get your bindings up to date with these changes. They will be
included in the next minor release. Sorry again!
Major features include:
- Real caching and refcounting on parsed objects
- Real caching and refcounting on objects read from the ODB
- Streaming writes & reads from the ODB
- Single-method writes for all object types
- The external API is now partially thread-safe
The speed increases are significant in all aspects, specially when
reading an object several times from the ODB (revwalking) and when
writing big objects to the ODB.
Here's a full changelog for the external API:
blob.h
------
- Remove `git_blob_new`
- Remove `git_blob_set_rawcontent`
- Remove `git_blob_set_rawcontent_fromfile`
- Rename `git_blob_writefile` -> `git_blob_create_fromfile`
- Change `git_blob_create_fromfile`:
The `path` argument is now relative to the repository's working dir
- Add `git_blob_create_frombuffer`
commit.h
--------
- Remove `git_commit_new`
- Remove `git_commit_add_parent`
- Remove `git_commit_set_message`
- Remove `git_commit_set_committer`
- Remove `git_commit_set_author`
- Remove `git_commit_set_tree`
- Add `git_commit_create`
- Add `git_commit_create_v`
- Add `git_commit_create_o`
- Add `git_commit_create_ov`
tag.h
-----
- Remove `git_tag_new`
- Remove `git_tag_set_target`
- Remove `git_tag_set_name`
- Remove `git_tag_set_tagger`
- Remove `git_tag_set_message`
- Add `git_tag_create`
- Add `git_tag_create_o`
tree.h
------
- Change `git_tree_entry_2object`:
New signature is `(git_object **object_out, git_repository *repo, git_tree_entry *entry)`
- Remove `git_tree_new`
- Remove `git_tree_add_entry`
- Remove `git_tree_remove_entry_byindex`
- Remove `git_tree_remove_entry_byname`
- Remove `git_tree_clearentries`
- Remove `git_tree_entry_set_id`
- Remove `git_tree_entry_set_name`
- Remove `git_tree_entry_set_attributes`
object.h
------------
- Remove `git_object_new
- Remove `git_object_write`
- Change `git_object_close`:
This method is now *mandatory*. Not closing an object causes a
memory leak.
odb.h
-----
- Remove type `git_rawobj`
- Remove `git_rawobj_close`
- Rename `git_rawobj_hash` -> `git_odb_hash`
- Change `git_odb_hash`:
New signature is `(git_oid *id, const void *data, size_t len, git_otype type)`
- Add type `git_odb_object`
- Add `git_odb_object_close`
- Change `git_odb_read`:
New signature is `(git_odb_object **out, git_odb *db, const git_oid *id)`
- Change `git_odb_read_header`:
New signature is `(size_t *len_p, git_otype *type_p, git_odb *db, const git_oid *id)`
- Remove `git_odb_write`
- Add `git_odb_open_wstream`
- Add `git_odb_open_rstream`
odb_backend.h
-------------
- Change type `git_odb_backend`:
New internal signatures are as follows
int (* read)(void **, size_t *, git_otype *, struct git_odb_backend *, const git_oid *)
int (* read_header)(size_t *, git_otype *, struct git_odb_backend *, const git_oid *)
int (* writestream)(struct git_odb_stream **, struct git_odb_backend *, size_t, git_otype)
int (* readstream)( struct git_odb_stream **, struct git_odb_backend *, const git_oid *)
- Add type `git_odb_stream`
- Add enum `git_odb_streammode`
Signed-off-by: Vicent Marti <tanoku@gmail.com>
