Subversion Repositories HelenOS

Rev

Rev 3264 | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
3259 decky 1
#
2
# Copyright (c) 2008 Martin Decky
3
# All rights reserved.
4
#
5
# Redistribution and use in source and binary forms, with or without
6
# modification, are permitted provided that the following conditions
7
# are met:
8
#
9
# - Redistributions of source code must retain the above copyright
10
#   notice, this list of conditions and the following disclaimer.
11
# - Redistributions in binary form must reproduce the above copyright
12
#   notice, this list of conditions and the following disclaimer in the
13
#   documentation and/or other materials provided with the distribution.
14
# - The name of the author may not be used to endorse or promote products
15
#   derived from this software without specific prior written permission.
16
#
17
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
#
28
"""
3262 decky 29
Convert descriptive structure definitions to structure object
3259 decky 30
"""
31
 
32
import struct
33
 
3262 decky 34
class Struct:
35
    def size(self):
36
        return struct.calcsize(self._format_)
3259 decky 37
 
3262 decky 38
    def pack(self):
3264 decky 39
        args = []
40
        for variable in self._args_:
41
            if (isinstance(self.__dict__[variable], list)):
42
                for item in self.__dict__[variable]:
43
                    args.append(item)
44
            else:
45
                args.append(self.__dict__[variable])
3262 decky 46
 
3264 decky 47
        return struct.pack(self._format_, *args)
3262 decky 48
 
49
def create(definition):
50
    "Create structure object"
51
 
3259 decky 52
    tokens = definition.split(None)
53
 
54
    # Initial byte order tag
3262 decky 55
    format = {
3259 decky 56
        "little:":  lambda: "<",
57
        "big:":     lambda: ">",
58
        "network:": lambda: "!"
59
    }[tokens[0]]()
3262 decky 60
    inst = Struct()
3264 decky 61
    args = []
3260 decky 62
 
3259 decky 63
    # Member tags
3260 decky 64
    comment = False
3263 decky 65
    variable = None
3259 decky 66
    for token in tokens[1:]:
3260 decky 67
        if (comment):
68
            if (token == "*/"):
69
                comment = False
70
            continue
71
 
3263 decky 72
        if (token == "/*"):
73
            comment = True
3262 decky 74
            continue
75
 
3263 decky 76
        if (variable != None):
77
            subtokens = token.split("[")
78
 
79
            if (len(subtokens) > 1):
80
                format += "%d" % int(subtokens[1].split("]")[0])
81
 
82
            format += variable
83
 
84
            inst.__dict__[subtokens[0]] = None
3264 decky 85
            args.append(subtokens[0])
3263 decky 86
 
87
            variable = None
88
            continue
89
 
90
        if (token[0:8] == "padding["):
3262 decky 91
            size = token[8:].split("]")[0]
92
            format += "%dx" % int(size)
3263 decky 93
            continue
94
 
95
        variable = {
96
            "char":     lambda: "s",
97
            "uint8_t":  lambda: "B",
98
            "uint16_t": lambda: "H",
99
            "uint32_t": lambda: "L",
100
            "uint64_t": lambda: "Q",
101
 
102
            "int8_t":   lambda: "b",
103
            "int16_t":  lambda: "h",
104
            "int32_t":  lambda: "l",
105
            "int64_t":  lambda: "q"
106
        }[token]()
3259 decky 107
 
3262 decky 108
    inst.__dict__['_format_'] = format
3264 decky 109
    inst.__dict__['_args_'] = args
3262 decky 110
    return inst