Allow UseDelta option to specify a delta ratio

Rework the frontend and backend to allow passing a ratio value in for
UseDelta rather than having a hardcoded #define-d 0.7 value always used.
This is useful for those with fast connections, who would likely benefit
from tuning this ratio to lower values; it is also useful for general
testing purposes.

The libalpm API changes for this, but we do support the old config file
format with a no-value 'UseDelta' option; in this case we simply use the
old default of 0.7.

We clamp the ratio values to a sane range between 0.0 and 2.0, allowing
ratios above 1.0 for testing purposes.

Signed-off-by: Dan McGee <dan@archlinux.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/lib/libalpm/delta.c b/lib/libalpm/delta.c
index 726f03c0..e3acc666 100644
--- a/lib/libalpm/delta.c
+++ b/lib/libalpm/delta.c
@@ -264,7 +264,8 @@ static alpm_list_t *find_unused(alpm_list_t *deltas, const char *to, off_t quota
 alpm_list_t SYMEXPORT *alpm_pkg_unused_deltas(alpm_pkg_t *pkg)
 {
 	ASSERT(pkg != NULL, return NULL);
-	return find_unused(pkg->deltas, pkg->filename, pkg->size * MAX_DELTA_RATIO);
+	return find_unused(pkg->deltas, pkg->filename,
+			pkg->size * pkg->handle->deltaratio);
 }
 
 /** @} */