This makes the lock management on the index a little bit broader,
having a number of routines hold the lock across looking up the
item to be modified and actually making the modification. Still
not true thread safety, but more pure index modifications are now
safe which allows the simple cases (such as starting up a diff
while index modifications are underway) safe enough to get the
snapshot without hitting allocation problems.
As part of this, I simplified the allocation of index entries to
use a flex array and just put the path at the end of the index
entry. This makes every entry self-contained and makes it a
little easier to feel sure that pointers to strings aren't
being accidentally copied and freed while other references are
still being held.
* Make GIT_INLINE an internal definition so it cannot be used in
public headers
* Fix language in CONTRIBUTING
* Make index caps API use signed instead of unsigned values
This changes the behavior of callbacks so that the callback error
code is not converted into GIT_EUSER and instead we propagate the
return value through to the caller. Instead of using the
giterr_capture and giterr_restore functions, we now rely on all
functions to pass back the return value from a callback.
To avoid having a return value with no error message, the user
can call the public giterr_set_str or some such function to set
an error message. There is a new helper 'giterr_set_callback'
that functions can invoke after making a callback which ensures
that some error message was set in case the callback did not set
one.
In places where the sign of the callback return value is
meaningful (e.g. positive to skip, negative to abort), only the
negative values are returned back to the caller, obviously, since
the other values allow for continuing the loop.
The hardest parts of this were in the checkout code where positive
return values were overloaded as meaningful values for checkout.
I fixed this by adding an output parameter to many of the internal
checkout functions and removing the overload. This added some
code, but it is probably a better implementation.
There is some funkiness in the network code where user provided
callbacks could be returning a positive or a negative value and
we want to rely on that to cancel the loop. There are still a
couple places where an user error might get turned into GIT_EUSER
there, I think, though none exercised by the tests.
This adds giterr_user_cancel to return GIT_EUSER and clear any
error message that is sitting around. As a result of using that
in places, we need to be more thorough with capturing errors that
happen inside a callback when used internally. To help with that,
this also adds giterr_capture and giterr_restore so that when we
internally use a foreach-type function that clears errors and
converts them to GIT_EUSER, it is easier to restore not just the
return value, but the actual error message text.
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.
This removes the one-off GIT_CDECL and adds a new standard way of
doing this named GIT_STDLIB_CALL with a src/win32 specific def
when on the Windows platform.
There has been discussion for a while about making some set of
the `giterr_set` type functions part of the public API for code
that is implementing new backends to libgit2. This makes the
`giterr_set_str()` and `giterr_set_oom()` functions public.
For the transition, http is going to keep its own logic until the
git/common code catches up with the implied multi_ack that http
has. This also has the side-effect of making the code cleaner and more
correct regardingt he protocol.
If it's not available, an error saying so will be returned when trying
to use a https:// URL.
This also unifies a lot of the network code to use git_transport in
many places instead of an socket descriptor.
Includes:
- Proper error reporting when encountering syntax errors in a
config file (file, line number, column).
- Rewritten `config_write`, now with 99% less goto-spaghetti
- Error state in `git_filebuf`: filebuf write functions no longer
need to be checked for error returns. If any of the writes performed
on a buffer fail, the last call to `git_filebuf_commit` or
`git_filebuf_hash` will fail accordingly and set the appropiate error
message. Baller!
The ownership semantics have been changed all over the library to be
consistent. There are no more "borrowed" or duplicated references.
Main changes:
- `git_repository_open2` and `3` have been dropped.
- Added setters and getters to hotswap all the repository owned
objects:
`git_repository_index`
`git_repository_set_index`
`git_repository_odb`
`git_repository_set_odb`
`git_repository_config`
`git_repository_set_config`
`git_repository_workdir`
`git_repository_set_workdir`
Now working directories/index files/ODBs and so on can be
hot-swapped after creating a repository and between operations.
- All these objects now have proper ownership semantics with
refcounting: they all require freeing after they are no longer
needed (the repository always keeps its internal reference).
- Repository open and initialization has been updated to keep in
mind the configuration files. Bare repositories are now always
detected, and a default config file is created on init.
- All the tests affected by these changes have been dropped from the
old test suite and ported to the new one.
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.
GCC produces several -Wuninitialized warnings. Most of them can be fixed
if we make visible for gcc that git__throw() and git__rethrow() always
return first argument.
Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
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");
