From: Michael Tremer <michael.tremer@ipfire.org>
Date: Fri, 13 Apr 2012 15:41:32 +0000 (+0200)
Subject: New feature: python scriptlets.
X-Git-Tag: 0.9.22~13
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=536bec815a842b0ea3d482c183257905f84debf6;p=pakfire.git

New feature: python scriptlets.
---

diff --git a/python/pakfire/actions.py b/python/pakfire/actions.py
index 1434841f4..cdc277891 100644
--- a/python/pakfire/actions.py
+++ b/python/pakfire/actions.py
@@ -20,6 +20,7 @@
 ###############################################################################
 
 import os
+import sys
 
 import chroot
 import packages
@@ -142,6 +143,23 @@ class ActionScript(Action):
 		# Load the scriplet.
 		self.scriptlet = self.pkg.get_scriptlet(self.script_action)
 
+	def get_lang(self):
+		if not self.scriptlet:
+			return
+
+		interp = None
+
+		for line in self.scriptlet.splitlines():
+			if line.startswith("#!/"):
+				interp = "exec"
+				break
+
+			elif line.startswith("#<lang: "):
+				interp = line[8:].replace(">", "")
+				break
+
+		return interp
+
 	@property
 	def interpreter(self):
 		"""
@@ -161,6 +179,22 @@ class ActionScript(Action):
 		# Actually run the scriplet.
 		log.debug("Running scriptlet %s" % self)
 
+		# Check of what kind the scriptlet is and run the
+		# corresponding handler.
+		lang = self.get_lang()
+
+		if lang == "exec":
+			self.run_exec()
+
+		elif lang == "python":
+			self.run_python()
+
+		else:
+			raise ActionError, _("Could not handle scriptlet of unknown type. Skipping.")
+
+	def run_exec(self):
+		log.debug(_("Executing python scriptlet..."))
+
 		# Check if the interpreter does exist and is executable.
 		if self.interpreter:
 			interpreter = "%s/%s" % (self.pakfire.path, self.interpreter)
@@ -224,6 +258,48 @@ class ActionScript(Action):
 			except OSError:
 				log.debug("Could not remove scriptlet file: %s" % script_file)
 
+	def run_python(self):
+		# This functions creates a fork with then chroots into the
+		# pakfire root if necessary and then compiles the given scriptlet
+		# code and runs it.
+
+		log.debug(_("Executing python scriptlet..."))
+
+		# Create fork.
+		pid = os.fork()
+
+		if not pid:
+			# child code
+
+			# The child chroots into the pakfire path.
+			if not self.pakfire.path == "/":
+				os.chroot(self.pakfire.path)
+
+			# Create a clean global environment, where only
+			# builtin functions are available and the os and sys modules.
+			_globals = {
+				"os"  : os,
+				"sys" : sys,
+			}
+
+			# Compile the scriptlet and execute it.
+			try:
+				obj = compile(self.scriptlet, "<string>", "exec")
+				eval(obj, _globals, {})
+
+			except Exception, e:
+				print _("Exception occured: %s") % e
+				os._exit(1)
+
+			# End the child process without cleaning up.
+			os._exit(0)
+
+		else:
+			# parent code
+
+			# Wait until the child process has finished.
+			os.waitpid(pid, 0)
+
 
 class ActionScriptPreIn(ActionScript):
 	script_action = "prein"
diff --git a/python/pakfire/packages/lexer.py b/python/pakfire/packages/lexer.py
index 2e662c9a0..09a8215eb 100644
--- a/python/pakfire/packages/lexer.py
+++ b/python/pakfire/packages/lexer.py
@@ -51,7 +51,7 @@ LEXER_PACKAGE_LINE    = LEXER_BLOCK_LINE
 LEXER_PACKAGE_END     = LEXER_BLOCK_END
 LEXER_PACKAGE_INHERIT = re.compile(r"^template ([A-Z0-9]+)$")
 
-LEXER_SCRIPTLET_BEGIN = re.compile(r"^script ([a-z]+)\s?(/[A-Za-z0-9\-\_/]+)?$")
+LEXER_SCRIPTLET_BEGIN = re.compile(r"^script ([a-z]+)\s?(shell|python)?$")
 LEXER_SCRIPTLET_LINE  = LEXER_BLOCK_LINE
 LEXER_SCRIPTLET_END   = LEXER_BLOCK_END
 
@@ -626,15 +626,11 @@ class TemplateLexer(DefaultLexer):
 		if self.scriptlets.has_key(name):
 			raise Exception, "Scriptlet %s is already defined" % name
 
-		path = m.group(2)
-		if path:
-			self.scriptlets[name] = {
-				"lang" : "bin",
-				"path" : self.expand_string(path),
-			}
-			return
+		lang = m.group(2) or "shell"
+		lines = [
+			"#<lang: %s>" % lang,
+		]
 
-		lines = []
 		while True:
 			line = self.get_line(self._lineno, raw=True)
 
@@ -658,8 +654,8 @@ class TemplateLexer(DefaultLexer):
 			raise LexerUnhandledLine, "%d: %s" % (self.lineno, line)
 
 		self.scriptlets[name] = {
-			"lang"      : "shell",
-			"scriptlet" : "\n".join(lines),
+			"lang"      : lang,
+			"scriptlet" : self.expand_string("\n".join(lines)),
 		}
 
 	def get_scriptlet(self, name):
diff --git a/python/pakfire/packages/packager.py b/python/pakfire/packages/packager.py
index 3ff3c384d..c756b0c5a 100644
--- a/python/pakfire/packages/packager.py
+++ b/python/pakfire/packages/packager.py
@@ -455,7 +455,9 @@ class BinaryPackager(Packager):
 			# Write script to a file.
 			scriptlet_file = self.mktemp()
 
-			if scriptlet["lang"] == "bin":
+			lang = scriptlet["lang"]
+
+			if lang == "bin":
 				path = lang["path"]
 				try:
 					f = open(path, "b")
@@ -474,14 +476,13 @@ class BinaryPackager(Packager):
 				f.close()
 				s.close()
 
-			elif scriptlet["lang"] == "shell":
+			elif lang == "shell":
 				s = open(scriptlet_file, "w")
 
 				# Write shell script to file.
 				s.write("#!/bin/sh -e\n\n")
 				s.write(scriptlet["scriptlet"])
 				s.write("\n\nexit 0\n")
-
 				s.close()
 
 				if scriptlet_name in SCRIPTS_PREREQUIRES:
@@ -490,6 +491,12 @@ class BinaryPackager(Packager):
 
 					prerequires += self.builder.find_prerequires(scriptlet_file)
 
+			elif lang == "python":
+				# Write the code to the scriptlet file.
+				s = open(scriptlet_file, "w")
+				s.write(scriptlet["scriptlet"])
+				s.close()
+
 			else:
 				raise Exception, "Unknown scriptlet language: %s" % scriptlet["lang"]