* Fixed #18: Builds fail on Ubuntu 13.04 with zlib.h missing.

* Fixed missing rebuild of build.py when the previous build failed.

buildozer/__init__.py

@@ -48,7 +48,19 @@ LOG_LEVELS_C = (RED, BLUE, BLACK)
 LOG_LEVELS_T = 'EID'
 
 
-class BuildozerCommandException(Exception):
+class BuildozerException(Exception):
+    '''
+    Exception raised for general situations buildozer cannot process.
+    '''
+    pass
+
+
+class BuildozerCommandException(BuildozerException):
+    '''
+    Exception raised when an external command failed.
+    
+    See: `Buildozer.cmd()`.
+    '''
     pass
 
 
@@ -1033,9 +1045,13 @@ def run():
         # don't show the exception in the command line. The log already show the
         # command failed.
         pass
+    except BuildozerException as error:
+        Buildozer().error('%s' % error)
 
 def run_remote():
     try:
         BuildozerRemote().run_command(sys.argv[1:])
     except BuildozerCommandException:
         pass
+    except BuildozerException as error:
+        Buildozer().error('%s' % error)

buildozer/targets/android.py

@@ -19,6 +19,7 @@ import traceback
 import os
 from pipes import quote
 from sys import platform, executable
+from buildozer import BuildozerException
 from buildozer.target import Target
 from os import environ
 from os.path import join, realpath, expanduser
@@ -105,6 +106,14 @@ class TargetAndroid(Target):
             self.javac_cmd = self._locate_java('javac')
             self.keytool_cmd = self._locate_java('keytool')
 
+        _, _, returncode_dpkg = self.buildozer.cmd(
+                'dpkg --version', break_on_error= False)
+        is_debian_like = (returncode_dpkg == 0)
+        if is_debian_like:
+            if not self.buildozer.file_exists('/usr/include/zlib.h'):
+                message = 'zlib headers must be installed, run: sudo apt-get install zlib1g-dev'
+                raise BuildozerException(message) 
+
         checkbin = self.buildozer.checkbin
         checkbin('Git git', 'git')
         checkbin('Cython cython', 'cython')
@@ -329,7 +338,7 @@ class TargetAndroid(Target):
         need_compile = 0
         if last_requirements != android_requirements:
             need_compile = 1
-        if not self.buildozer.file_exists(self.pa_dir, 'dist', 'default'):
+        if not self.buildozer.file_exists(self.pa_dir, 'dist', 'default', 'build.py'):
             need_compile = 1
 
         if not need_compile: