state: rework changeset calculation algorithm

Calculate changesets directly by stabilizating the package graph instead of
recalculating the whole graph and then diffing (similar approach as seen
in 'smart' package manager). The algorithm is not complete: defferred
search space forking is missing. So you don't always get a solution on
complex graphs.

Benefits:
- usually the search state tree is smaller (less memory used)
- speed relational to changeset size, not database size (usually faster)
- touch only packages related to users request (can work on partitially
  broken state; upgrades only necessary packages, fixes #7)

Also implemented:
- command prompt to confirm operation if packages are deleted or downgraded
- requesting deletion of package suggests removal of all packages depending
  on the package being removed (you'll get list of packages that also get
  removed if you want package X removed)
- option --simulate to see what would have been done (mainly for testing)
- an untested implementation of versioned dependencies and conflicts

A lot has changed, so expect new bugs too.

1 files changed, 8 insertions, 2 deletions

diff --git a/src/apk_defines.h b/src/apk_defines.h
index 4a42b16..e8029de 100644
--- a/src/apk_defines.h
+++ b/src/apk_defines.h
@@ -50,8 +50,14 @@ extern csum_t bad_checksum;
 #define csum_valid(buf)			memcmp(buf, bad_checksum, sizeof(csum_t))
 #endif
 
-extern int apk_cwd_fd, apk_verbosity, apk_progress, apk_upgrade;
-extern int apk_clean, apk_force;
+extern int apk_cwd_fd, apk_verbosity;
+extern unsigned int apk_flags;
+
+#define APK_FORCE		0x0001
+#define APK_SIMULATE		0x0002
+#define APK_CLEAN_PROTECTED	0x0004
+#define APK_PROGRESS		0x0008
+#define APK_UPGRADE		0x0010
 
 #define apk_error(args...)	apk_log("ERROR: ", args);
 #define apk_warning(args...)	if (apk_verbosity > 0) { apk_log("WARNING: ", args); }