Mega-commit with improvements and changes done in the past days.

- Introduce package states: unpacked, broken, installed, etc.
  Not yet finished, only unpacked and installed are used for now.

- Move package metadata files in binary packages directly to
  the top directory, this speeds up some ops and makes easier to
  continue working in future changes.

- xbps-bin: -C flag to check the hash of package files has been
  superseded by the 'check' target, which verifies the integrity
  of an installed package.

- Use the 'essential' object when upgrading packages, overwritting
  current files. This is needed for critical packages like sh, libc
  and others.

- Miscellaneous tweaks and improvements thorough the code.

--HG--
extra : convert_revision : 2073fcc123efc24b3e9327b5e22aa91752f20df6

doc/BINPKG_INFO

@@ -5,22 +5,27 @@
 A binary package built with xbps is a normal tar(1) archive, compressed
 with bzip2 and has the following structure:
 
-	/
-	/usr ------|
-	/var ------| => Package structure that will be installed.
-	/etc ------|
+	Package metadata
+	-----------------
+	/INSTALL
+	/REMOVE
+	/files.plist
+	/props.plist
+
+	Package data
+	-----------------
+	/usr
+	/var
+	/etc
 	...
-	/var/db/xbps/metadata/$pkgname
-	/var/db/xbps/metadata/$pkgname/files.plist
-	/var/db/xbps/metadata/$pkgname/props.plist
-	/var/db/xbps/metadata/$pkgname/INSTALL
-	/var/db/xbps/metadata/$pkgname/REMOVE
 
 Metadata info is stored in the "/var/db/xbps/metadata/$pkgname"
-directory and two files will be always be present: flist and props.plist.
+directory and two files will be always be present: files.plist
+and props.plist.
 
 The files.plist file contains the list of files/links/dirs that package
 will install, as well as SHA256 hashes for files.
+
 The props.plist file contains package metadata properties and has the
 following structure:
 

doc/TODO

@@ -29,13 +29,9 @@ xbps-bin:
  * Implement shell style match patterns with fnmatch().
  * Make -f flag to overwrite files when installing, and to ignore
    files with wrong checksum or unexistent when removing.
- * Add a target to check pkg integrity: normal files, metadata
-   and its dependencies.
 
 libxbps:
  * Fix glibc updates: removing libc is bad.
- * Create xbps_upgrade_pkg() to replace or remove/unpack and register.
-   Remove duplicate code from xbps-bin/install.c. [IN PROGRESS]
  * Add support to upgrade packages but overwritting current files;
    this will fix libc, sh and others. An "essential" boolean obj
    seems to be a good way to find such packages, like dpkg. [IN PROGRESS]