环境
主机： ubuntu14.04 64bit
开发板： qemu + vexpress-a9
工具链： arm-none-linux-gnueabi-gcc (gcc version 4.8.3 20140320)
Python版本： Python-2.7.13
概述
前面一篇博文（交叉编译Python-2.7.13到ARM（aarch32）平台）介绍了移植python到aarch32上面，但是发现有很多模块都不能用，可以在板子上面执行下面的命令测试一下：
1 [root@vexpress ]# python /usr/lib/python2.7/test/test___all__.py
2 Traceback (most recent call last):
3 File "/usr/lib/python2.7/test/test___all__.py", line 3, in <module>
4 import unittest
5 File "/usr/lib/python2.7/unittest/__init__.py", line 58, in <module>
6 from .result import TestResult
7 File "/usr/lib/python2.7/unittest/result.py", line 9, in <module>
8 from . import util
9 File "/usr/lib/python2.7/unittest/util.py", line 2, in <module>
10 from collections import namedtuple, OrderedDict
11 File "/usr/lib/python2.7/collections.py", line 20, in <module>
12 from _collections import deque, defaultdict
13 ImportError: No module named _collections
可以看到这里找不到_collections模块。
对比x86_64的编译结果：
1 ls x86_64/build/lib.linux-x86_64-2.7/
2 array.so* _codecs_hk.so* cPickle.so* _curses_panel.so* future_builtins.so* itertools.so* mmap.so* parser.so* _socket.so* _sysconfigdata.py time.so*
3 audioop.so* _codecs_iso2022.so* crypt.so* _curses.so* grp.so* _json.so* _multibytecodec.so* pyexpat.so* spwd.so* _sysconfigdata.pyc unicodedata.so*
4 binascii.so* _codecs_jp.so* cStringIO.so* datetime.so* _hashlib.so* linuxaudiodev.so* _multiprocessing.so* _random.so* _sqlite3.so* _sysconfigdata.pyo zlib.so*
5 _bisect.so* _codecs_kr.so* _csv.so* _elementtree.so* _heapq.so* _locale.so* nis.so* readline.so* _ssl.so* syslog.so*
6 cmath.so* _codecs_tw.so* _ctypes.so* fcntl.so* _hotshot.so* _lsprof.so* operator.so* resource.so* strop.so* termios.so*
7 _codecs_cn.so* _collections.so* _ctypes_test.so* _functools.so* _io.so* math.so* ossaudiodev.so* select.so* _struct.so* _testcapi.so*
而aarch32的编译结果：
1 $ls aarch32/build/lib.linux2-arm-2.7/
2 audioop.so* _codecs_iso2022.so* _codecs_tw.so* _ctypes.so* _elementtree.so* _json.so* mmap.so* nis.so* resource.so* termios.so*
3 _codecs_cn.so* _codecs_jp.so* crypt.so* _ctypes_test.so* future_builtins.so* linuxaudiodev.so* _multibytecodec.so* parser.so* _sysconfigdata.py _testcapi.so*
4 _codecs_hk.so* _codecs_kr.so* _csv.so* datetime.so* _hotshot.so* _lsprof.so* _multiprocessing.so* pyexpat.so* _sysconfigdata.pyc
可以看到，aarch32上面缺少了很多库， 比如_collections.so，将来这些库会被安装到/usr/lib/python2.7/lib-dynload下面， 所以下面要说的就是将缺少的这些库弄回来！
正文1、通过分析setup.py发现问题
在函数build_extensions中刚开始self.extensions中存放的是需要编译库， 通过在加打印：
1 diff --git a/setup.py b/setup.py
2 index 54054c2..bc16bb1 100644
3 --- a/setup.py
4 +++ b/setup.py
5 @@ -178,6 +178,7 @@ class PyBuildExt(build_ext):
6
7 def build_extensions(self):
8
9 + print "build_extensions enter."
10 # Detect which modules should be compiled
11 missing = self.detect_modules()
12
13 @@ -191,6 +192,9 @@ class PyBuildExt(build_ext):
14 extensions.append(ctypes)
15 self.extensions = extensions
16
17 + for ext in self.extensions:
18 + print "extensions: ", ext.name
19 +
20 # Fix up the autodetected modules, prefixing all the source files
21 # with Modules/ and adding Python's include directory to the path.
22 (srcdir,) = sysconfig.get_config_vars('srcdir')
23 @@ -217,6 +221,8 @@ class PyBuildExt(build_ext):
24 # Python header files
25 headers = [sysconfig.get_config_h_filename()]
26 headers += glob(os.path.join(sysconfig.get_path('include'), "*.h"))
27 +
28 + print "builtin_module_names: ", sys.builtin_module_names
29 for ext in self.extensions[:]:
30 ext.sources = [ find_module_file(filename, moddirlist)
31 for filename in ext.sources ]
32 @@ -248,10 +254,15 @@ class PyBuildExt(build_ext):
33 remove_modules.append(line[0])
34 input.close()
35
36 + print "remove_modules: ", remove_modules
37 +
38 for ext in self.extensions[:]:
39 if ext.name in remove_modules:
40 self.extensions.remove(ext)
41
42 + for ext in self.extensions[:]:
43 + print "extensions: ", ext.name
44 +
45 # When you run "make CC=altcc" or something similar, you really want
46 # those environment variables passed into the setup.py phase. Here's
47 # a small set of useful ones.
48 @@ -1618,13 +1629,13 @@ class PyBuildExt(build_ext):
49
50
51 # Platform-specific libraries
52 - if host_platform == 'linux2':
53 + if host_platform == 'linux2' or host_platform == 'linux2-arm':
54 # Linux-specific modules
55 exts.append( Extension('linuxaudiodev', ['linuxaudiodev.c']) )
56 else:
57 missing.append('linuxaudiodev')
58
59 - if (host_platform in ('linux2', 'freebsd4', 'freebsd5', 'freebsd6',
60 + if (host_platform in ('linux2','linux2-arm' 'freebsd4', 'freebsd5', 'freebsd6',
61 'freebsd7', 'freebsd8')
62 or host_platform.startswith("gnukfreebsd")):
63 exts.append( Extension('ossaudiodev', ['ossaudiodev.c']) )
64 @@ -1755,6 +1766,10 @@ class PyBuildExt(build_ext):
65 ## ext = Extension('xx', ['xxmodule.c'])
66 ## self.extensions.append(ext)
67
68 +# print "missing: ", missing
69 +# for ext in self.extensions:
70 +# print "extensions: ", ext.name
71 +
72 return missing
73
74 def detect_tkinter_explicitly(self):
75 @@ -2229,6 +2244,8 @@ Topic :: Software Development
76 """
77
78 def main():
79 + print "sys.path: ", sys.path
80 + print "cross_compiling: ", cross_compiling
81 # turn off warnings when deprecated modules are imported
82 import warnings
83 warnings.filterwarnings("ignore",category=DeprecationWarning)
然后执行./mk2_make.sh可以看到：
1 sys.path: ['/home/pengdonglin/src/qemu/python_cross_compile/Python-2.7.13', '/home/pengdonglin/src/qemu/python_cross_compile/aarch32/build/lib.linux2-arm-2.7', '/home/pengdonglin/src/qemu/python_cross_compile/Python-2.7.13/Lib', '/home/pengdonglin/src/qemu/python_cross_compile/Python-2.7.13/Lib/plat-linux2', '/usr/lib/python2.7', '/usr/lib/python2.7/plat-x86_64-linux-gnu', '/usr/lib/python2.7/lib-tk', '/usr/lib/python2.7/lib-old', '/usr/lib/python2.7/lib-dynload']
2 cross_compiling: True
3 build_extensions enter.
4 extensions: _struct
5 extensions: _ctypes_test
6 extensions: array
7 extensions: cmath
8 extensions: math
9 extensions: strop
10 extensions: time
11 extensions: datetime
12 extensions: itertools
13 extensions: future_builtins
14 extensions: _random
15 extensions: _collections
16 extensions: _bisect
17 extensions: _heapq
18 extensions: operator
19 extensions: _io
20 extensions: _functools
21 extensions: _json
22 extensions: _testcapi
23 extensions: _hotshot
24 extensions: _lsprof
25 extensions: unicodedata
26 extensions: _locale
27 extensions: fcntl
28 extensions: pwd
29 extensions: grp
30 extensions: spwd
31 extensions: select
32 extensions: parser
33 extensions: cStringIO
34 extensions: cPickle
35 extensions: mmap
36 extensions: syslog
37 extensions: audioop
38 extensions: crypt
39 extensions: _csv
40 extensions: _socket
41 extensions: _sha
42 extensions: _md5
43 extensions: _sha256
44 extensions: _sha512
45 extensions: termios
46 extensions: resource
47 extensions: nis
48 extensions: binascii
49 extensions: pyexpat
50 extensions: _elementtree
51 extensions: _multibytecodec
52 extensions: _codecs_kr
53 extensions: _codecs_jp
54 extensions: _codecs_cn
55 extensions: _codecs_tw
56 extensions: _codecs_hk
57 extensions: _codecs_iso2022
58 extensions: _multiprocessing
59 extensions: linuxaudiodev
60 extensions: _ctypes
61 builtin_module_names: ('__builtin__', '__main__', '_ast', '_bisect', '_codecs', '_collections', '_functools', '_heapq', '_io', '_locale', '_md5', '_random', '_sha', '_sha256', '_sha512', '_socket', '_sre', '_struct', '_symtable', '_warnings', '_weakref', 'array', 'binascii', 'cPickle', 'cStringIO', 'cmath', 'errno', 'exceptions', 'fcntl', 'gc', 'grp', 'imp', 'itertools', 'marshal', 'math', 'operator', 'posix', 'pwd', 'select', 'signal', 'spwd', 'strop', 'sys', 'syslog', 'thread', 'time', 'unicodedata', 'xxsubtype', 'zipimport', 'zlib')
62 remove_modules: ['DESTLIB=$(LIBDEST)', 'MACHDESTLIB=$(BINLIBDEST)', 'DESTPATH=', 'SITEPATH=', 'TESTPATH=', 'MACHDEPPATH=:$(PLATDIR)', 'EXTRAMACHDEPPATH=', 'TKPATH=:lib-tk', 'OLDPATH=:lib-old', 'COREPYTHONPATH=$(DESTPATH)$(SITEPATH)$(TESTPATH)$(MACHDEPPATH)$(EXTRAMACHDEPPATH)$(TKPATH)$(OLDPATH)', 'PYTHONPATH=$(COREPYTHONPATH)', 'posix', 'errno', 'pwd', '_sre', '_codecs', '_weakref', 'zipimport', '_symtable', 'GLHACK=-Dclear=__GLclear', 'xxsubtype']
63 extensions: _ctypes_test
64 extensions: datetime
65 extensions: future_builtins
66 extensions: _json
67 extensions: _testcapi
68 extensions: _hotshot
69 extensions: _lsprof
70 extensions: parser
71 extensions: mmap
72 extensions: audioop
73 extensions: crypt
74 extensions: _csv
75 extensions: termios
76 extensions: resource
77 extensions: nis
78 extensions: pyexpat
79 extensions: _elementtree
80 extensions: _multibytecodec
81 extensions: _codecs_kr
82 extensions: _codecs_jp
83 extensions: _codecs_cn
84 extensions: _codecs_tw
85 extensions: _codecs_hk
86 extensions: _codecs_iso2022
87 extensions: _multiprocessing
88 extensions: linuxaudiodev
89 extensions: _ctypes
90 Python build finished, but the necessary bits to build these modules were not found:
91 _bsddb _curses _curses_panel
92 _sqlite3 _ssl _tkinter
93 bsddb185 bz2 dbm
94 dl gdbm imageop
95 ossaudiodev readline sunaudiodev
96 zlib
97 To find the necessary bits, look in setup.py in detect_modules() for the module's name.
在刚开始的时候，self.extensions中还是全的，但是经过下面的处理后， 很多库都被remove了：
1 for ext in self.extensions[:]:
2 ext.sources = [ find_module_file(filename, moddirlist)
3 for filename in ext.sources ]
4 if ext.depends is not None:
5 ext.depends = [find_module_file(filename, moddirlist)
6 for filename in ext.depends]
7 else:
8 ext.depends = []
9 # re-compile extensions if a header file has been changed
10 ext.depends.extend(headers)
11 # platform specific include directories
12 ext.include_dirs.extend(incdirlist)
13 # If a module has already been built statically,
14 # don't build it here
15 if ext.name in sys.builtin_module_names:
16 self.extensions.remove(ext)
第15行的注释可以看到，如果sys.builtin_module_names中含有extensions中的库，那么这个库就会从extensions中remove。从目前的分析看，交叉编译的时候，setup.py的import sys导入的应该是PC机上面的环境，导致sys.builtin_module_names的值也是PC上面python运行环境的值（可以在PC的终端下输入python，查看sys.builtin_module_names的值）。
2、 解决
这里为了简单起见，我们只需把刚才出问题的判断注释掉，如下：
1 @@ -233,8 +239,8 @@ class PyBuildExt(build_ext):
2
3 # If a module has already been built statically,
4 # don't build it here
5 - if ext.name in sys.builtin_module_names:
6 - self.extensions.remove(ext)
7 + #if ext.name in sys.builtin_module_names:
8 + # self.extensions.remove(ext)
9
10 # Parse Modules/Setup and Modules/Setup.local to figure out which
11 # modules are turned on in the file.
然后重新配置、编译、安装， 最后重新制作ramdisk文件，启动板子，重新执行下面的测试：
1 [root@vexpress ]# python /usr/lib/python2.7/test/test___all__.py
2 test_all (__main__.AllTest) ... BaseHTTPServer
3 Bastion
4 CGIHTTPServer
5 ConfigParser
6 Cookie
7 DocXMLRPCServer
8 HTMLParser
9 MimeWriter
10 Queue
11 SimpleHTTPServer
12 ... ...
13 'xml.sax.xmlreader', 'xmllib', 'xmlrpclib']
14 Following modules failed to be imported: ['ctypes.wintypes', 'dbhash', 'gzip', 'idlelib.AutoComplete']
15 ok
16 ----------------------------------------------------------------------
17 Ran 1 test in 9.345s
18 OK
可以看到，测试成功了。
下面开始一致sqlite3到板子上面，同时让python也增加多sqlite3的支持。
3、支持sqlite3
首先到http://www.sqlite.org/download.html 下载最新的sqlite3的源码，这里我用的是sqlite-autoconf-3170000.tar.gz，然后进行交叉编译，下面是交叉编译的脚本mk.sh:
1 #!/bin/bash
2 export PATH=/home/pengdonglin/src/qemu/aarch32/arm-2014.05/bin:$PATH
3
4 ../sqlite-autoconf-3170000/configure --host=arm-none-linux-gnueabi \
5 --prefix=`pwd`
6
7 make -j4
8 make install
然后修改制作ramdisk的脚本：
1 #!/bin/bash
2
3 sudo rm -rf rootfs
4 sudo rm -rf tmpfs
5 sudo rm -rf ramdisk*
6
7 sudo mkdir rootfs
8 sudo cp ../busybox-1.24.2/_install/* rootfs/ -raf
9
10 sudo mkdir -p rootfs/proc/
11 sudo mkdir -p rootfs/sys/
12 sudo mkdir -p rootfs/tmp/
13 sudo mkdir -p rootfs/root/
14 sudo mkdir -p rootfs/var/
15 sudo mkdir -p rootfs/mnt/
16
17 sudo cp etc rootfs/ -arf
18
19 sudo cp -arf ../arm-2014.05/arm-none-linux-gnueabi/libc/lib rootfs/
20
21 #python
22 sudo mkdir -p rootfs/usr
23 pushd rootfs/usr
24 sudo cp -raf /home/pengdonglin/qemu/thiry_part/Python/aarch32/bin .
25 sudo cp -raf /home/pengdonglin/qemu/thiry_part/Python/aarch32/lib .
26 sudo cp -raf /home/pengdonglin/qemu/thiry_part/Python/aarch32/include .
27 sudo cp -raf /home/pengdonglin/qemu/thiry_part/Python/aarch32/share .
28 sudo /home/pengdonglin/qemu/aarch32/arm-2014.05/bin/arm-none-linux-gnueabi-strip lib/python*
29 popd
30
31 #sqlite3
32 sudo cp -raf /home/pengdonglin/qemu/thiry_part/SQlite3/aarch32/bin/* rootfs/bin/
33 sudo cp -raf /home/pengdonglin/qemu/thiry_part/SQlite3/aarch32/include/* rootfs/include/
34 sudo cp -raf /home/pengdonglin/qemu/thiry_part/SQlite3/aarch32/lib/* rootfs/lib/
35 sudo cp -raf /home/pengdonglin/qemu/thiry_part/SQlite3/aarch32/share/* rootfs/usr/share
36
37
38 sudo mkdir -p rootfs/dev/
39 sudo mknod rootfs/dev/tty1 c 4 1
40 sudo mknod rootfs/dev/tty2 c 4 2
41 sudo mknod rootfs/dev/tty3 c 4 3
42 sudo mknod rootfs/dev/tty4 c 4 4
43 sudo mknod rootfs/dev/console c 5 1
44 sudo mknod rootfs/dev/null c 1 3
45
46 sudo rm -rf rootfs/lib/*.a
47 sudo rm -rf rootfs/lib/*.la
48 sudo ../arm-2014.05/bin/arm-none-linux-gnueabi-strip rootfs/lib/*
49
50 sudo dd if=/dev/zero of=ramdisk bs=1M count=100
51 sudo mkfs.ext4 -F ramdisk
52
53 sudo mkdir -p tmpfs
54 sudo mount -t ext4 ramdisk ./tmpfs/ -o loop
55 sudo cp -raf rootfs/* tmpfs/
56 sudo umount tmpfs
57
58 sudo gzip --best -c ramdisk > ramdisk.gz
59 sudo mkimage -n "ramdisk" -A arm -O linux -T ramdisk -C gzip -d ramdisk.gz ramdisk.img
这样在板子上面就可以使用sqlite3了，但是此时python还无法使用，需要重新编译python，并指定sqlite3的lib和include的路径，修改mk1_config.sh如下：
#!/bin/bash
export PATH=/home/pengdonglin/qemu/aarch32/arm-2014.05/bin:$PATH
../Python-2.7.13/configure --prefix=`pwd` \
--host=arm-none-linux-gnueabi \
--build=x86_64-linux-gnu \
--enable-ipv6 \
--enable-shared \
ac_cv_file__dev_ptmx="yes" \
ac_cv_file__dev_ptc="no" \
LDFLAGS="-L/home/pengdonglin/qemu/thiry_part/SQlite3/aarch32/lib" \
CPPFLAGS="-I/home/pengdonglin/qemu/thiry_part/SQlite3/aarch32/include"
这样在Makefile调用setup.py时就会将sqlite3相关的模块编译进来，然后再次执行mk2_make.sh和mk3_install.sh，然后我们可以检查一下：
1 $ls aarch32/build/lib.linux2-arm-2.7/
2 array.so* _codecs_hk.so* cPickle.so* datetime.so* _heapq.so* _locale.so* _multiprocessing.so* _random.so* _socket.so* _sysconfigdata.pyc
3 audioop.so* _codecs_iso2022.so* crypt.so* _elementtree.so* _hotshot.so* _lsprof.so* nis.so* resource.so* spwd.so* syslog.so*
4 binascii.so* _codecs_jp.so* cStringIO.so* fcntl.so* _io.so* math.so* operator.so* select.so* _sqlite3.so* termios.so*
5 _bisect.so* _codecs_kr.so* _csv.so* _functools.so* itertools.so* _md5.so* ossaudiodev.so* _sha256.so* strop.so* _testcapi.so*
6 cmath.so* _codecs_tw.so* _ctypes.so* future_builtins.so* _json.so* mmap.so* parser.so* _sha512.so* _struct.so* time.so*
7 _codecs_cn.so* _collections.so* _ctypes_test.so* grp.so* linuxaudiodev.so* _multibytecodec.so* pyexpat.so* _sha.so* _sysconfigdata.py unicodedata.so*
可以看到，库已经很全了。
4、测试
重新制作ramdisk文件，启动系统。
编写测试sqlite3的脚本sq_demo.py如下：
1 #!/usr/bin/python
2
3 import sqlite3
4
5 #open database
6 conn = sqlite3.connect('test.db')
7 print "Opened database successfully";
8
9 conn.execute('''CREATE TABLE COMPANY
10 (ID INT PRIMARY KEY NOT NULL,
11 NAME TEXT NOT NULL,
12 AGE INT NOT NULL,
13 ADDRESS CHAR(50),
14 SALARY REAL);''')
15 print "Table created successfully";
16
17 #insert
18 conn.execute("INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) \
19 VALUES (1, 'Paul', 32, 'California', 20000.00 )");
20
21 conn.execute("INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) \
22 VALUES (2, 'Allen', 25, 'Texas', 15000.00 )");
23
24 conn.execute("INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) \
25 VALUES (3, 'Teddy', 23, 'Norway', 20000.00 )");
26
27 conn.execute("INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) \
28 VALUES (4, 'Mark', 25, 'Rich-Mond ', 65000.00 )");
29
30 conn.commit()
31 print "Records created successfully";
32
33 #select
34 cursor = conn.execute("SELECT id, name, address, salary from COMPANY")
35 for row in cursor:
36 print "ID = ", row[0]
37 print "NAME = ", row[1]
38 print "ADDRESS = ", row[2]
39 print "SALARY = ", row[3], "\n"
40
41 print "Operation done successfully";
42
43 #delect
44 conn.execute("DELETE from COMPANY where ID=2;")
45 conn.commit()
46 print "Total number of rows deleted :", conn.total_changes
47
48 cursor = conn.execute("SELECT id, name, address, salary from COMPANY")
49 for row in cursor:
50 print "ID = ", row[0]
51 print "NAME = ", row[1]
52 print "ADDRESS = ", row[2]
53 print "SALARY = ", row[3], "\n"
54
55 print "Operation done successfully";
56
57 conn.close()
下面是输出结果：
[root@vexpress ]# python /tmp/sq_demo.py
Opened database successfully
Table created successfully
Records created successfully
ID = 1
NAME = Paul
ADDRESS = California
SALARY = 20000.0
ID = 2
NAME = Allen
ADDRESS = Texas
SALARY = 15000.0
ID = 3
NAME = Teddy
ADDRESS = Norway
SALARY = 20000.0
ID = 4
NAME = Mark
ADDRESS = Rich-Mond
SALARY = 65000.0
Operation done successfully
Total number of rows deleted : 5
ID = 1
NAME = Paul
ADDRESS = California
SALARY = 20000.0
ID = 3
NAME = Teddy
ADDRESS = Norway
SALARY = 20000.0
ID = 4
NAME = Mark
ADDRESS = Rich-Mond
SALARY = 65000.0
Operation done successfully
完。
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