Implemented find_unique_short_oid for pack backend, based on git sha1 lookup method;
finding an object given its full oid is just a particular case of searching
the unique object matching an oid prefix (short oid).
Added git_odb_read_unique_short_oid, which iterates over all the backends to
find and read the unique object matching the given oid prefix.
Added a git_object_lookup_short_oid method to find the unique object in
the repository matching a given oid prefix : it generalizes git_object_lookup
which now does nothing but calls git_object_lookup_short_oid.
"git_config_backend" have been renamed to "git_config_file", which
implements a generic interface to access a configuration file -- be it
either on disk, from a DB or whatever mumbojumbo.
I think this makes more sense.
Configuration options can come from different sources. Currently,
there is only support for reading them from a flat file, but it might
make sense to read it from a database at some point.
Move the parsing code into src/config_file.c and create an include
file include/git2/config_backend.h to allow for other backends to be
developed.
Signed-off-by: Carlos Martín Nieto <cmn@elego.de>
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");
Removed the optional `replace` argument, we now have 4 add methods:
`git_index_add`: add or update from path
`git_index_add2`: add or update from struct
`git_index_append`: add without replacing from path
`git_index_append2`: add without replacing from struct
Yes, this breaks the bindings.
New external functions:
- git_index_unmerged_entrycount: Counts the unmerged entries in
the index
- git_index_get_unmerged: Gets an unmerged entry from the index
by name
New internal functions:
- read_unmerged: Wrapper for read_unmerged_internal
- read_unmerged_internal: Reads unmerged entries from the index
if the index has the INDEX_EXT_UNMERGED_SIG set
- unmerged_srch: Search function for unmerged vector
- unmerged_cmp: Compare function for unmerged vector
New data structures:
- git_index now contains a git_vector unmerged that stores
unmerged entries
- git_index_entry_unmerged: Representation of an unmerged file
entry. It represents all three versions of the file at the
same time, with one name, three modes and three OIDs
When in the middle of a merge, the index needs to contain several files
with the same name. git_index_insert() used to prevent this by not adding a new entry if an entry with the same name already existed.
Most tags will have a timestamp of whenever the code is running and
dealing with time and timezones is error-prone. Optimize for this case
by adding a function which causes the signature to be created with a
current timestamp.
Signed-off-by: Carlos Martín Nieto <cmn@elego.de>
git_repository_path() and git_repository_workdir() respectively return the path to the git repository and the working directory. Those paths are absolute and normalized.
