Aside from reducing the code by 20 lines this refactoring removes
a level of indirection when trying to access the operations of a
given transport "instance", making the code clearer and easier to
follow.
It also has the nice effect of giving us the benefits of C99 style
struct initialization (namely ".fetch = X") without requiring that
level of language support from our compiler. We don't need to worry
about new operation methods being added as they will now be NULL'd
out automatically by the xcalloc() we use to create the new struct
transport we supply to the caller.
This pattern already exists in struct walker, so we already have
a precedent for it in Git. We also don't really need to worry
about any sort of performance decreases that may occur as a result
of filling out 4-8 op pointers when we make a "struct transport".
The extra few CPU cycles this requires over filling in the "struct
transport_ops" is killed by the time it will take Git to actually
*use* one of those functions, as most transport operations are
going over the wire or will be copying object data locally between
two directories.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If a transport doesn't support an option we already are telling
the higher level application (fetch or push) that the option is not
valid by sending back a >0 return value from transport_set_option
so there's not a strong motivation to have the function perform the
output itself. Instead we should let the higher level application
do the output if it is necessary. This avoids always telling the
user that depth isn't supported on HTTP urls even when they did
not pass a --depth option to git-fetch.
If the user passes an option and the option value is invalid we now
properly die in git-fetch instead of just spitting out a message
and running anyway. This mimics prior behavior better where
incorrect/malformed options are not accepted by the process.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
We don't actually need to know at the time of transport_get if the
caller wants to fetch, push, or do both on the returned object.
It is easier to just delay the initialization of the HTTP walker
until we know we will need it by providing a CURL specific fetch
function in the curl_transport that makes sure the walker instance
is initialized before use.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We always allocate and return a struct transport* right now as every
URL is considered to be a native Git transport if it is not rsync,
http/https/ftp or a bundle. So we can simplify the initialization
of a new transport object by performing one xcalloc call and filling
in only the attributes required.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When using the walker API within builtin-fetch we don't allow
it to update refs locally; instead that action is reserved for
builtin-fetch's own main loop once the objects have actually
been downloaded.
Passing NULL here will bypass the unnecessary malloc/free of a
string buffer within the walker API. That buffer is never used
because the prior argument (the refs to update) is also NULL.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
fetch_pack() can call remove_duplicates() on its input array and
this will possibly overwrite an earlier entry with a later one if
there are any duplicates in the input array. In such a case the
caller here might then attempt to free an item multiple times as
it goes through its cleanup.
I also forgot to free the heads array we pass down into fetch_pack()
when I introduced the allocation of it in this function during my
builtin-fetch cleanup series. Better free it while we are here
working on related memory management fixes.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
If we are using a native packfile to perform a git-fetch invocation
and the received packfile contained more than the configured limits
of fetch.unpackLimit/transfer.unpackLimit then index-pack will output
a single line saying "keep\t$sha1\n" to stdout. This line needs to
be captured and retained so we can delete the corresponding .keep
file ("$GIT_DIR/objects/pack/pack-$sha1.keep") once all refs have
been safely updated.
This trick has long been in use with git-fetch.sh and its lower level
helper git-fetch--tool as a way to allow index-pack to save the new
packfile before the refs have been updated and yet avoid a race with
any concurrently running git-repack process. It was unfortunately
lost when git-fetch.sh was converted to pure C and fetch--tool was
no longer being invoked.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit walkers need to know the SHA-1 name of any objects they
have been asked to fetch while the native pack transport only
wants to know the names of the remote refs as the remote side
must do the name->SHA-1 translation.
Since we only have three fetch implementations and one of them
(bundle) doesn't even need the name information we can reduce
the code required to perform a fetch by having just one function
and passing of the filtered list of refs to be fetched. Each
transport can then obtain the information it needs from that ref
array to construct its own internal operation state.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Conflicts:
transport.c
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The ALLOC_GROW macro is a shorter way to implement an array that
grows upon demand as additional items are added to it. We have
mostly standardized upon its use within git and transport.c is
not an exception.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This moves the code to call push backends into a library that can be
extended to make matching fetch and push decisions based on the URL it
gets, and which could be changed to have built-in implementations
instead of calling external programs.
Signed-off-by: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
