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1# this file contains definitions related to the Linux kernel itself
2#
3
4# list here the macros that you know are always defined/undefined when including
5# the kernel headers
6#
7import sys, cpp, re, os.path, string, time
8from defaults import *
9
10verboseSearch = 0
11verboseFind   = 0
12
13########################################################################
14########################################################################
15#####                                                              #####
16#####           H E A D E R   S C A N N E R                        #####
17#####                                                              #####
18########################################################################
19########################################################################
20
21
22class HeaderScanner:
23    """a class used to non-recursively detect which Linux kernel headers are
24       used by a given set of input source files"""
25
26    # to use the HeaderScanner, do the following:
27    #
28    #    scanner = HeaderScanner()
29    #    for path in <your list of files>:
30    #        scanner.parseFile(path)
31    #
32    #    # get the set of Linux headers included by your files
33    #    headers = scanner.getHeaders()
34    #
35    #    # get the set of of input files that do include Linux headers
36    #    files   = scanner.getFiles()
37    #
38    #    note that the result of getHeaders() is a set of strings, each one
39    #    corresponding to a non-bracketed path name, e.g.:
40    #
41    #        set("linux/types","asm/types.h")
42    #
43
44    # the default algorithm is pretty smart and will analyze the input
45    # files with a custom C pre-processor in order to optimize out macros,
46    # get rid of comments, empty lines, etc..
47    #
48    # this avoids many annoying false positives... !!
49    #
50
51    # this regular expression is used to detect include paths that relate to
52    # the kernel, by default, it selects one of:
53    #    <linux/*>
54    #    <asm/*>
55    #    <asm-generic/*>
56    #    <mtd/*>
57    #
58    re_combined =\
59       re.compile(r"^.*<((%s)/[\d\w_\+\.\-/]*)>.*$" % string.join(kernel_dirs,"|") )
60    # some kernel files choose to include files with relative paths (x86 32/64
61    # dispatch for instance)
62    re_rel_dir = re.compile(r'^.*"([\d\w_\+\.\-/]+)".*$')
63
64    def __init__(self,config={}):
65        """initialize a HeaderScanner"""
66        self.reset()
67        self.config = config
68
69    def reset(self,config={}):
70        self.files    = set()  # set of files being parsed for headers
71        self.headers  = {}     # maps headers to set of users
72        self.config   = config
73
74    def checkInclude(self, line, from_file, kernel_root=None):
75        relative = False
76        m = HeaderScanner.re_combined.match(line)
77        if kernel_root and not m:
78            m = HeaderScanner.re_rel_dir.match(line)
79            relative = True
80        if not m: return
81
82        header = m.group(1)
83        if from_file:
84            self.files.add(from_file)
85            if kernel_root and relative:
86                hdr_dir = os.path.realpath(os.path.dirname(from_file))
87                hdr_dir = hdr_dir.replace("%s/" % os.path.realpath(kernel_root),
88                                          "")
89                if hdr_dir:
90                    _prefix = "%s/" % hdr_dir
91                else:
92                    _prefix = ""
93                header = "%s%s" % (_prefix, header)
94
95        if not header in self.headers:
96            self.headers[header] = set()
97
98        if from_file:
99            if verboseFind:
100                print "=== %s uses %s" % (from_file, header)
101            self.headers[header].add(from_file)
102
103    def parseFile(self, path, arch=None, kernel_root=None):
104        """parse a given file for Linux headers"""
105        if not os.path.exists(path):
106            return
107
108        # since tokenizing the file is very slow, we first try a quick grep
109        # to see if this returns any meaningful results. only if this is true
110        # do we do the tokenization"""
111        try:
112            f = open(path, "rt")
113        except:
114            print "!!! can't read '%s'" % path
115            return
116
117        hasIncludes = False
118        for line in f:
119            if (HeaderScanner.re_combined.match(line) or
120                (kernel_root and HeaderScanner.re_rel_dir.match(line))):
121                hasIncludes = True
122                break
123
124        if not hasIncludes:
125            if verboseSearch: print "::: " + path
126            return
127
128        if verboseSearch: print "*** " + path
129
130        list = cpp.BlockParser().parseFile(path)
131        if list:
132            #list.removePrefixed("CONFIG_",self.config)
133            macros = kernel_known_macros.copy()
134            if kernel_root:
135                macros.update(self.config)
136                if arch and arch in kernel_default_arch_macros:
137                    macros.update(kernel_default_arch_macros[arch])
138            list.optimizeMacros(macros)
139            list.optimizeIf01()
140            includes = list.findIncludes()
141            for inc in includes:
142                self.checkInclude(inc, path, kernel_root)
143
144    def getHeaders(self):
145        """return the set of all needed kernel headers"""
146        return set(self.headers.keys())
147
148    def getHeaderUsers(self,header):
149        """return the set of all users for a given header"""
150        return set(self.headers.get(header))
151
152    def getAllUsers(self):
153        """return a dictionary mapping heaaders to their user set"""
154        return self.headers.copy()
155
156    def getFiles(self):
157        """returns the set of files that do include kernel headers"""
158        return self.files.copy()
159
160
161##########################################################################
162##########################################################################
163#####                                                                #####
164#####           H E A D E R   F I N D E R                            #####
165#####                                                                #####
166##########################################################################
167##########################################################################
168
169
170class KernelHeaderFinder:
171    """a class used to scan the kernel headers themselves."""
172
173    # this is different
174    #  from a HeaderScanner because we need to translate the path returned by
175    #  HeaderScanner.getHeaders() into possibly architecture-specific ones.
176    #
177    # for example, <asm/XXXX.h> needs to be translated in <asm-ARCH/XXXX.h>
178    # where ARCH is appropriately chosen
179
180    # here's how to use this:
181    #
182    #    scanner = HeaderScanner()
183    #    for path in <your list of user sources>:
184    #        scanner.parseFile(path)
185    #
186    #    used_headers = scanner.getHeaders()
187    #    finder       = KernelHeaderFinder(used_headers, [ "arm", "x86" ],
188    #                                      "<kernel_include_path>")
189    #    all_headers  = finder.scanForAllArchs()
190    #
191    #   not that the result of scanForAllArchs() is a list of relative
192    #   header paths that are not bracketed
193    #
194
195    def __init__(self,headers,archs,kernel_root,kernel_config):
196        """init a KernelHeaderScanner,
197
198            'headers' is a list or set of headers,
199            'archs' is a list of architectures
200            'kernel_root' is the path to the 'include' directory
201             of your original kernel sources
202        """
203
204        if len(kernel_root) > 0 and kernel_root[-1] != "/":
205            kernel_root += "/"
206        #print "using kernel_root %s" % kernel_root
207        self.archs         = archs
208        self.searched      = set(headers)
209        self.kernel_root   = kernel_root
210        self.kernel_config = kernel_config
211        self.needed        = {}
212        self.setArch(arch=None)
213
214    def setArch(self,arch=None):
215        self.curr_arch = arch
216        self.arch_headers = set()
217        if arch:
218            self.prefix = "asm-%s/" % arch
219        else:
220            self.prefix = None
221
222    def pathFromHeader(self,header):
223        path = header
224        if self.prefix and path.startswith("asm/"):
225            path = "%s%s" % (self.prefix, path[4:])
226        return path
227
228    def pathToHeader(self,path):
229        if self.prefix and path.startswith(self.prefix):
230            path = "asm/%s" % path[len(self.prefix):]
231        return "%s" % path
232
233    def setSearchedHeaders(self,headers):
234        self.searched = set(headers)
235
236    def scanForArch(self):
237        fparser   = HeaderScanner(config=self.kernel_config)
238        workqueue = []
239        needed    = {}
240        for h in self.searched:
241            path = self.pathFromHeader(h)
242            if not path in needed:
243                needed[path] = set()
244            workqueue.append(path)
245
246        i = 0
247        while i < len(workqueue):
248            path = workqueue[i]
249            i   += 1
250            fparser.parseFile(self.kernel_root + path,
251                              arch=self.curr_arch, kernel_root=self.kernel_root)
252            for used in fparser.getHeaders():
253                path  = self.pathFromHeader(used)
254                if not path in needed:
255                    needed[path] = set()
256                    workqueue.append(path)
257                for user in fparser.getHeaderUsers(used):
258                    needed[path].add(user)
259
260        # now copy the arch-specific headers into the global list
261        for header in needed.keys():
262            users = needed[header]
263            if not header in self.needed:
264                self.needed[header] = set()
265
266            for user in users:
267                self.needed[header].add(user)
268
269    def scanForAllArchs(self):
270        """scan for all architectures and return the set of all needed kernel headers"""
271        for arch in self.archs:
272            self.setArch(arch)
273            self.scanForArch()
274
275        return set(self.needed.keys())
276
277    def getHeaderUsers(self,header):
278        """return the set of all users for a given header"""
279        return set(self.needed[header])
280
281    def getArchHeaders(self,arch):
282        """return the set of all <asm/...> headers required by a given architecture"""
283        return set()  # XXX: TODO
284
285#####################################################################################
286#####################################################################################
287#####                                                                           #####
288#####           C O N F I G   P A R S E R                                       #####
289#####                                                                           #####
290#####################################################################################
291#####################################################################################
292
293class ConfigParser:
294    """a class used to parse the Linux kernel .config file"""
295    re_CONFIG_ = re.compile(r"^(CONFIG_\w+)=(.*)$")
296
297    def __init__(self):
298        self.items = {}
299        self.duplicates = False
300
301    def parseLine(self,line):
302        line = string.strip(line)
303
304        # skip empty and comment lines
305        if len(line) == 0 or line[0] == "#":
306            return
307
308        m = ConfigParser.re_CONFIG_.match(line)
309        if not m: return
310
311        name  = m.group(1)
312        value = m.group(2)
313
314        if name in self.items:  # aarg, duplicate value
315            self.duplicates = True
316
317        self.items[name] = value
318
319    def parseFile(self,path):
320        f = file(path, "r")
321        for line in f:
322            if len(line) > 0:
323                if line[-1] == "\n":
324                    line = line[:-1]
325                    if len(line) > 0 and line[-1] == "\r":
326                        line = line[:-1]
327                self.parseLine(line)
328        f.close()
329
330    def getDefinitions(self):
331        """retrieve a dictionary containing definitions for CONFIG_XXX"""
332        return self.items.copy()
333
334    def __repr__(self):
335        return repr(self.items)
336
337    def __str__(self):
338        return str(self.items)
339