1 files changed, 41 insertions, 0 deletions
diff --git a/pomu/util/pkg.py b/pomu/util/pkg.py
new file mode 100644
index 0000000..26fdb39
--- /dev/null
+++ b/pomu/util/pkg.py
@@ -0,0 +1,41 @@
+"""
+A set of utility function to manipulate package descriptions
+"""
+
+import re
+
+from pomu.util.portage import suffixes
+from pomu.util.str import pivot
+
+def ver_str(vernum, suff, rev):
+    """Gets the string representation of the version (specified by number, suffix and rev)"""
+    return vernum + (suff if suff else '') + (rev if rev else '')
+
+def cpv_split(pkg):
+    """
+    Extracts category, name, version number, suffix, revision from a package descriptor
+    e.g. dev-libs/openssl-0.9.8z_p8-r100 -> dev-libs, openssl, 0.9.8z, p8, r100
+    """
+    # dev-libs/openssl-0.9.8z_p8-r100
+    category, _, pkg = pkg.rpartition('/') # category may be omitted
+    # openssl-0.9.8z_p8-r100
+    m = re.search(r'-r\d+$', pkg) # revision is optional
+    if m:
+        pkg, rev = pivot(pkg, m.start(0), False)
+    else:
+        rev = None
+    # openssl-0.9.8z_p8
+    m = re.search(r'_({})(\d*)$'.format('|'.join(suffixes)), pkg)
+    if m:
+        pkg, suff = pivot(pkg, m.start(0), False)
+    else:
+        suff = None
+    # openssl-0.9.8z
+    m = re.search(r'-(\d+(\.\d+)*)([a-z])?$', pkg)
+    if m:
+        pkg, vernum = pivot(pkg, m.start(0), False)
+    else:
+        vernum = None
+    # openssl
+    name = pkg
+    return category, name, vernum, suff, rev