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
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
|
Each recipe consists of 3 main parts: defining identifiers, setting build
variables, and defining build commands.
The package "mylib" will be used here as an example
General tips:
- mylib_foo is written as $(package)_foo in order to make recipes more similar.
- Secondary dependency packages relative to the bitcoin binaries/libraries (i.e.
those not in `ALLOWED_LIBRARIES` in `contrib/devtools/symbol-check.py`) don't
need to be shared and should be built statically whenever possible. See
[below](#secondary-dependencies) for more details.
## Identifiers
Each package is required to define at least these variables:
$(package)_version:
Version of the upstream library or program. If there is no version, a
placeholder such as 1.0 can be used.
$(package)_download_path:
Location of the upstream source, without the file-name. Usually http, https
or ftp. Secure transmission options like https should be preferred if
available.
$(package)_file_name:
The upstream source filename available at the download path.
$(package)_sha256_hash:
The sha256 hash of the upstream file
These variables are optional:
$(package)_build_subdir:
cd to this dir before running configure/build/stage commands.
$(package)_download_file:
The file-name of the upstream source if it differs from how it should be
stored locally. This can be used to avoid storing file-names with strange
characters.
$(package)_dependencies:
Names of any other packages that this one depends on.
$(package)_patches:
Filenames of any patches needed to build the package
$(package)_extra_sources:
Any extra files that will be fetched via $(package)_fetch_cmds. These are
specified so that they can be fetched and verified via 'make download'.
## Build Variables:
After defining the main identifiers, build variables may be added or customized
before running the build commands. They should be added to a function called
$(package)_set_vars. For example:
define $(package)_set_vars
...
endef
Most variables can be prefixed with the host, architecture, or both, to make
the modifications specific to that case. For example:
Universal: $(package)_cc=gcc
Linux only: $(package)_linux_cc=gcc
x86_64 only: $(package)_x86_64_cc = gcc
x86_64 linux only: $(package)_x86_64_linux_cc = gcc
These variables may be set to override or append their default values.
$(package)_cc
$(package)_cxx
$(package)_objc
$(package)_objcxx
$(package)_ar
$(package)_ranlib
$(package)_libtool
$(package)_nm
$(package)_cflags
$(package)_cxxflags
$(package)_ldflags
$(package)_cppflags
$(package)_config_env
$(package)_build_env
$(package)_stage_env
$(package)_build_opts
$(package)_config_opts
The *_env variables are used to add environment variables to the respective
commands.
Many variables respect a debug/release suffix as well, in order to use them for
only the appropriate build config. For example:
$(package)_cflags_release = -O3
$(package)_cflags_i686_debug = -g
$(package)_config_opts_release = --disable-debug
These will be used in addition to the options that do not specify
debug/release. All builds are considered to be release unless DEBUG=1 is set by
the user. Other variables may be defined as needed.
## Build commands:
For each build, a unique build dir and staging dir are created. For example,
`work/build/mylib/1.0-1adac830f6e` and `work/staging/mylib/1.0-1adac830f6e`.
The following build commands are available for each recipe:
$(package)_fetch_cmds:
Runs from: build dir
Fetch the source file. If undefined, it will be fetched and verified
against its hash.
$(package)_extract_cmds:
Runs from: build dir
Verify the source file against its hash and extract it. If undefined, the
source is assumed to be a tarball.
$(package)_preprocess_cmds:
Runs from: build dir/$(package)_build_subdir
Preprocess the source as necessary. If undefined, does nothing.
$(package)_config_cmds:
Runs from: build dir/$(package)_build_subdir
Configure the source. If undefined, does nothing.
$(package)_build_cmds:
Runs from: build dir/$(package)_build_subdir
Build the source. If undefined, does nothing.
$(package)_stage_cmds:
Runs from: build dir/$(package)_build_subdir
Stage the build results. If undefined, does nothing.
The following variables are available for each recipe:
$(1)_staging_dir: package's destination sysroot path
$(1)_staging_prefix_dir: prefix path inside of the package's staging dir
$(1)_extract_dir: path to the package's extracted sources
$(1)_build_dir: path where configure/build/stage commands will be run
$(1)_patch_dir: path where the package's patches (if any) are found
Notes on build commands:
For packages built with autotools, $($(package)_autoconf) can be used in the
configure step to (usually) correctly configure automatically. Any
$($(package)_config_opts) will be appended.
Most autotools projects can be properly staged using:
$(MAKE) DESTDIR=$($(package)_staging_dir) install
## Build outputs:
In general, the output of a depends package should not contain any libtool
archives. Instead, the package should output `.pc` (`pkg-config`) files where
possible.
From the [Gentoo Wiki entry](https://wiki.gentoo.org/wiki/Project:Quality_Assurance/Handling_Libtool_Archives):
> Libtool pulls in all direct and indirect dependencies into the .la files it
> creates. This leads to massive overlinking, which is toxic to the Gentoo
> ecosystem, as it leads to a massive number of unnecessary rebuilds.
## Secondary dependencies:
Secondary dependency packages relative to the bitcoin binaries/libraries (i.e.
those not in `ALLOWED_LIBRARIES` in `contrib/devtools/symbol-check.py`) don't
need to be shared and should be built statically whenever possible. This
improves general build reliability as illustrated by the following example:
When linking an executable against a shared library `libprimary` that has its
own shared dependency `libsecondary`, we may need to specify the path to
`libsecondary` on the link command using the `-rpath/-rpath-link` options, it is
not sufficient to just say `libprimary`.
For us, it's much easier to just link a static `libsecondary` into a shared
`libprimary`. Especially because in our case, we are linking against a dummy
`libprimary` anyway that we'll throw away. We don't care if the end-user has a
static or dynamic `libseconday`, that's not our concern. With a static
`libseconday`, when we need to link `libprimary` into our executable, there's no
dependency chain to worry about as `libprimary` has all the symbols.
## Build targets:
To build an individual package (useful for debugging), following build targets are available.
make ${package}
make ${package}_fetched
make ${package}_extracted
make ${package}_preprocessed
make ${package}_configured
make ${package}_built
make ${package}_staged
make ${package}_postprocessed
make ${package}_cached
make ${package}_cached_checksum
|
