summaryrefslogtreecommitdiffstats
path: root/src/rocksdb/build_tools/amalgamate.py
blob: f79e9075e3af5a7f5148ab849985e5e03b7a522f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
#!/usr/bin/python
# Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.

# amalgamate.py creates an amalgamation from a unity build.
# It can be run with either Python 2 or 3.
# An amalgamation consists of a header that includes the contents of all public
# headers and a source file that includes the contents of all source files and
# private headers.
#
# This script works by starting with the unity build file and recursively expanding
# #include directives. If the #include is found in a public include directory,
# that header is expanded into the amalgamation header.
#
# A particular header is only expanded once, so this script will
# break if there are multiple inclusions of the same header that are expected to
# expand differently. Similarly, this type of code causes issues:
#
# #ifdef FOO
#   #include "bar.h"
#   // code here
# #else
#   #include "bar.h"            // oops, doesn't get expanded
#   // different code here
# #endif
#
# The solution is to move the include out of the #ifdef.

from __future__ import print_function

import argparse
import re
import sys
from os import path

include_re = re.compile('^[ \t]*#include[ \t]+"(.*)"[ \t]*$')
included = set()
excluded = set()


def find_header(name, abs_path, include_paths):
    samedir = path.join(path.dirname(abs_path), name)
    if path.exists(samedir):
        return samedir
    for include_path in include_paths:
        include_path = path.join(include_path, name)
        if path.exists(include_path):
            return include_path
    return None


def expand_include(
    include_path,
    f,
    abs_path,
    source_out,
    header_out,
    include_paths,
    public_include_paths,
):
    if include_path in included:
        return False

    included.add(include_path)
    with open(include_path) as f:
        print('#line 1 "{}"'.format(include_path), file=source_out)
        process_file(
            f, include_path, source_out, header_out, include_paths, public_include_paths
        )
    return True


def process_file(
    f, abs_path, source_out, header_out, include_paths, public_include_paths
):
    for (line, text) in enumerate(f):
        m = include_re.match(text)
        if m:
            filename = m.groups()[0]
            # first check private headers
            include_path = find_header(filename, abs_path, include_paths)
            if include_path:
                if include_path in excluded:
                    source_out.write(text)
                    expanded = False
                else:
                    expanded = expand_include(
                        include_path,
                        f,
                        abs_path,
                        source_out,
                        header_out,
                        include_paths,
                        public_include_paths,
                    )
            else:
                # now try public headers
                include_path = find_header(filename, abs_path, public_include_paths)
                if include_path:
                    # found public header
                    expanded = False
                    if include_path in excluded:
                        source_out.write(text)
                    else:
                        expand_include(
                            include_path,
                            f,
                            abs_path,
                            header_out,
                            None,
                            public_include_paths,
                            [],
                        )
                else:
                    sys.exit(
                        "unable to find {}, included in {} on line {}".format(
                            filename, abs_path, line
                        )
                    )

            if expanded:
                print('#line {} "{}"'.format(line + 1, abs_path), file=source_out)
        elif text != "#pragma once\n":
            source_out.write(text)


def main():
    parser = argparse.ArgumentParser(
        description="Transform a unity build into an amalgamation"
    )
    parser.add_argument("source", help="source file")
    parser.add_argument(
        "-I",
        action="append",
        dest="include_paths",
        help="include paths for private headers",
    )
    parser.add_argument(
        "-i",
        action="append",
        dest="public_include_paths",
        help="include paths for public headers",
    )
    parser.add_argument(
        "-x", action="append", dest="excluded", help="excluded header files"
    )
    parser.add_argument("-o", dest="source_out", help="output C++ file", required=True)
    parser.add_argument(
        "-H", dest="header_out", help="output C++ header file", required=True
    )
    args = parser.parse_args()

    include_paths = list(map(path.abspath, args.include_paths or []))
    public_include_paths = list(map(path.abspath, args.public_include_paths or []))
    excluded.update(map(path.abspath, args.excluded or []))
    filename = args.source
    abs_path = path.abspath(filename)
    with open(filename) as f, open(args.source_out, "w") as source_out, open(
        args.header_out, "w"
    ) as header_out:
        print('#line 1 "{}"'.format(filename), file=source_out)
        print('#include "{}"'.format(header_out.name), file=source_out)
        process_file(
            f, abs_path, source_out, header_out, include_paths, public_include_paths
        )


if __name__ == "__main__":
    main()