xref: /openbmc/openbmc/poky/bitbake/lib/bb/checksum.py (revision 9aee5003)
1# Local file checksum cache implementation
2#
3# Copyright (C) 2012 Intel Corporation
4#
5# SPDX-License-Identifier: GPL-2.0-only
6#
7
8import glob
9import operator
10import os
11import stat
12import bb.utils
13import logging
14from bb.cache import MultiProcessCache
15
16logger = logging.getLogger("BitBake.Cache")
17
18# mtime cache (non-persistent)
19# based upon the assumption that files do not change during bitbake run
20class FileMtimeCache(object):
21    cache = {}
22
23    def cached_mtime(self, f):
24        if f not in self.cache:
25            self.cache[f] = os.stat(f)[stat.ST_MTIME]
26        return self.cache[f]
27
28    def cached_mtime_noerror(self, f):
29        if f not in self.cache:
30            try:
31                self.cache[f] = os.stat(f)[stat.ST_MTIME]
32            except OSError:
33                return 0
34        return self.cache[f]
35
36    def update_mtime(self, f):
37        self.cache[f] = os.stat(f)[stat.ST_MTIME]
38        return self.cache[f]
39
40    def clear(self):
41        self.cache.clear()
42
43# Checksum + mtime cache (persistent)
44class FileChecksumCache(MultiProcessCache):
45    cache_file_name = "local_file_checksum_cache.dat"
46    CACHE_VERSION = 1
47
48    def __init__(self):
49        self.mtime_cache = FileMtimeCache()
50        MultiProcessCache.__init__(self)
51
52    def get_checksum(self, f):
53        f = os.path.normpath(f)
54        entry = self.cachedata[0].get(f)
55        cmtime = self.mtime_cache.cached_mtime(f)
56        if entry:
57            (mtime, hashval) = entry
58            if cmtime == mtime:
59                return hashval
60            else:
61                bb.debug(2, "file %s changed mtime, recompute checksum" % f)
62
63        hashval = bb.utils.md5_file(f)
64        self.cachedata_extras[0][f] = (cmtime, hashval)
65        return hashval
66
67    def merge_data(self, source, dest):
68        for h in source[0]:
69            if h in dest:
70                (smtime, _) = source[0][h]
71                (dmtime, _) = dest[0][h]
72                if smtime > dmtime:
73                    dest[0][h] = source[0][h]
74            else:
75                dest[0][h] = source[0][h]
76
77    def get_checksums(self, filelist, pn, localdirsexclude):
78        """Get checksums for a list of files"""
79
80        def checksum_file(f):
81            try:
82                checksum = self.get_checksum(f)
83            except OSError as e:
84                bb.warn("Unable to get checksum for %s SRC_URI entry %s: %s" % (pn, os.path.basename(f), e))
85                return None
86            return checksum
87
88        #
89        # Changing the format of file-checksums is problematic as both OE and Bitbake have
90        # knowledge of them. We need to encode a new piece of data, the portion of the path
91        # we care about from a checksum perspective. This means that files that change subdirectory
92        # are tracked by the task hashes. To do this, we do something horrible and put a "/./" into
93        # the path. The filesystem handles it but it gives us a marker to know which subsection
94        # of the path to cache.
95        #
96        def checksum_dir(pth):
97            # Handle directories recursively
98            if pth == "/":
99                bb.fatal("Refusing to checksum /")
100            pth = pth.rstrip("/")
101            dirchecksums = []
102            for root, dirs, files in os.walk(pth, topdown=True):
103                [dirs.remove(d) for d in list(dirs) if d in localdirsexclude]
104                for name in files:
105                    fullpth = os.path.join(root, name).replace(pth, os.path.join(pth, "."))
106                    checksum = checksum_file(fullpth)
107                    if checksum:
108                        dirchecksums.append((fullpth, checksum))
109            return dirchecksums
110
111        checksums = []
112        for pth in filelist.split():
113            exist = pth.split(":")[1]
114            if exist == "False":
115                continue
116            pth = pth.split(":")[0]
117            if '*' in pth:
118                # Handle globs
119                for f in glob.glob(pth):
120                    if os.path.isdir(f):
121                        if not os.path.islink(f):
122                            checksums.extend(checksum_dir(f))
123                    else:
124                        checksum = checksum_file(f)
125                        if checksum:
126                            checksums.append((f, checksum))
127            elif os.path.isdir(pth):
128                if not os.path.islink(pth):
129                    checksums.extend(checksum_dir(pth))
130            else:
131                checksum = checksum_file(pth)
132                if checksum:
133                    checksums.append((pth, checksum))
134
135        checksums.sort(key=operator.itemgetter(1))
136        return checksums
137