This means creating a new struct which can pass more descriptive data
from the back end sync functions to the downloader. In particular, we're
interested in the download size read from the sync DB. When the remote
server reports a size larger than this (via a content-length header),
abort the transfer.
In cases where the size is unknown, we set a hard upper limit of:
* 25MiB for a sync DB
* 16KiB for a signature
For reference, 25MiB is more than twice the size of all of the current
binary repos (with files) combined, and 16KiB is a truly gargantuan
signature.
Signed-off-by: Dave Reisner <dreisner@archlinux.org>
URLs might end with a slash and follow redirects, or could be a
generated by a script such as /getpkg.php?id=12345. In both cases, we
may have a better filename that we can write to, taken from either
content-disposition header, or the effective URL.
Specific to the first case, we write to a temporary file of the format
'alpmtmp.XXXXXX', where XXXXXX is randomized by mkstemp(3). Since this
is a randomly generated file, we cannot support resuming and the file is
unlinked in the event of an interrupt.
We also run into the possibility of changing out the filename from under
alpm on a -U operation, so callers of _alpm_download can optionally pass
a pointer to a *char to be filled in by curl_download_internal with the
actual filename we wrote to. Any sync operation will pass a NULL pointer
here, as we rely on specific names for packages from a mirror.
Fixes FS#22645.
Signed-off-by: Dave Reisner <d@falconindy.com>
There's a lot of related moving parts here:
* Iteration through mirrors is moved back to the calling functions. This
allows removal of _alpm_download_single_file and _alpm_download_files.
* The download function gets a few more arguments to influence behavior.
This allows several different scenarios to customize behavior:
- database
- database signature (req'd and optional)
- package
- package via direct URL
- package signature via direct URL (req'd and optional)
* For databases, we need signatures from the same mirror, so structure
the code accordingly.
Some-inspiration-from: Dave Reisner <d@falconindy.com>
Signed-off-by: Dan McGee <dan@archlinux.org>
This lets us determine the real size of the file on disk so that we can
properly bump the progress bar when we're resuming a download.
Signed-off-by: Dave Reisner <d@falconindy.com>
Signed-off-by: Dan McGee <dan@archlinux.org>
Sorry for this being such a huge patch, but I believe it is necessary for
quite a few reasons which I will attempt to explain herein. I've been
mulling this over for a while, but wasn't super happy with making the
download interface more complex. Instead, if we carefully order things in
the internal download code, we can actually make the interface simpler.
1. FS#15657 - This involves `name.db.tar.gz.part` files being left around the
filesystem, and then causing all sorts of issues when someone attempts to
rerun the operation they canceled. We need to ensure that if we resume a
download, we are resuming it on exactly the same file; if we cannot be
almost postive of that then we need to start over.
2. http://www.mail-archive.com/pacman-dev@archlinux.org/msg03536.html - Here
we have a lighttpd bug to ruin the day. If we send both a Range: header and
If-Modified-Since: header across the wire in a GET request, lighttpd doesn't
do what we want in several cases. If the file hadn't been modified, it
returns a '304 Not Modified' instead of a '206 Partial Content'. We need to
do a stat (e.g. HEAD in HTTP terms) operation here, and the proceed
accordingly based off the values we get back from it.
3. The mtime stuff was rather ugly, and relied on the called function to
write back to a passed in reference, which isn't the greatest. Instead, use
the power of the filesystem to contain this info. Every file downloaded
internally is now carefully timestamped with the remote file time. This
should allow the resume logic to work. In order to guarantee this, we need
to implement a signal handler that catches interrupts, notifies the running
code, and causes it to set the mtimes on the file. It then rethrows the
signal so the pacman signal handler (or any frontend) works as expected.
4. We did a lot of funky stuff in trying to track the DB last modified time.
It is a lot easier to just keep the downloaded DB file around and track the
time on that rather than in a funky dot file. It also kills a lot of code.
5. For GPG verification of the databases down the road, we are going to need
the DB file around for at least a short bit of time anyway, so this gets us
closer to that.
Signed-off-by: Dan McGee <dan@archlinux.org>
[Xav: fixed printf with off_t]
Signed-off-by: Xavier Chantry <shiningxc@gmail.com>
We no longer expose any of libdownload in our public functions, so no need
to include this header anymore.
Signed-off-by: Dan McGee <dan@archlinux.org>
Add new stub functions that work by calling the existing (terrible) download
forreal function, which needs a serious overhaul. Hide the existing
functions and switch all former users to the new functions.
Signed-off-by: Dan McGee <dan@archlinux.org>
This is the first in what will be a series of patches to clean up the
current download code in libalpm. Start by moving download code out of
server.c and into download.c.
Signed-off-by: Dan McGee <dan@archlinux.org>
Dave Reisner