The library I need to use is: https://github.com/madler/zlib .
To install it separately, I can do:
git clone https://github.com/madler/zlib
cd zlib
make
Then I can use it during compilation by including "-lz" flag, such as:
g -o main main.cpp std=c 17 -lz
I want to make "install zlib and build" a part of my bazel build, instead of asking a user to clone and build zlib manually.
My Bazel build file is as follow:
load("@rules_cc//cc:defs.bzl", "cc_binary")
cc_binary(
name = "hello-world",
srcs = ["hello-world.cc"],
copts = ["-std=c 17","-O3"],
linkopts = ["-lz"]
)
What should I add so that when I run "bazel build ...", zlib is also cloned and installed (make)?
Edit: hello-world.cc program to test compilation:
#include <ctime>
#include <string>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <iostream>
#include <optional>
#include <vector>
#include <zlib.h>
class GzReader {
private:
static constexpr int BUFFER_SIZE = 1 << 20;
const std::string filename_;
gzFile file_;
char *buffer_;
int line_size_, idx_, last_idx_;
bool finished_;
size_t line_count_;
public:
GzReader() = delete;
explicit GzReader(std::string filename) : filename_(filename) {
file_ = gzopen(filename_.c_str(), "r");
if (!file_) {
throw std::runtime_error("Could not open file");
}
buffer_ = new char[BUFFER_SIZE 1];
line_count_ = 0;
idx_ = 0;
last_idx_ = 0;
line_size_ = gzread(file_, buffer_, BUFFER_SIZE);
buffer_[line_size_] = '\0';
finished_ = (line_size_ == 0);
}
~GzReader() {
delete[] buffer_;
gzclose(file_);
}
};
static const char *file_name = "text.gz";
int main() {
GzReader reader(file_name);
return 0;
}
CodePudding user response：
Unfortunately Bazel does not have native support for dependencies that don't provide Bazel BUILD files.
You will have to set up your own zlib mirror with bazel wrapping.
Alternatively, there is a library here that makes it possible, but it will require some elbow grease.
They provide an example specifically for zlib.
CodePudding user response：
Create a zlib.BUILD with the following content:
# Copied from https://github.com/protocolbuffers/protobuf/blob/master/third_party/zlib.BUILD
# Copyright 2008 Google Inc. All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above
# copyright notice, this list of conditions and the following disclaimer
# in the documentation and/or other materials provided with the
# distribution.
# * Neither the name of Google Inc. nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
# Code generated by the Protocol Buffer compiler is owned by the owner
# of the input file used when generating it. This code is not
# standalone and requires a support library to be linked with it. This
# support library is itself covered by the above license.
load("@rules_cc//cc:defs.bzl", "cc_library")
licenses(["notice"]) # BSD/MIT-like license (for zlib)
_ZLIB_HEADERS = [
"crc32.h",
"deflate.h",
"gzguts.h",
"inffast.h",
"inffixed.h",
"inflate.h",
"inftrees.h",
"trees.h",
"zconf.h",
"zlib.h",
"zutil.h",
]
_ZLIB_PREFIXED_HEADERS = ["zlib/include/" hdr for hdr in _ZLIB_HEADERS]
# In order to limit the damage from the `includes` propagation
# via `:zlib`, copy the public headers to a subdirectory and
# expose those.
genrule(
name = "copy_public_headers",
srcs = _ZLIB_HEADERS,
outs = _ZLIB_PREFIXED_HEADERS,
cmd = "cp $(SRCS) $(@D)/zlib/include/",
)
cc_library(
name = "zlib",
srcs = [
"adler32.c",
"compress.c",
"crc32.c",
"deflate.c",
"gzclose.c",
"gzlib.c",
"gzread.c",
"gzwrite.c",
"infback.c",
"inffast.c",
"inflate.c",
"inftrees.c",
"trees.c",
"uncompr.c",
"zutil.c",
# Include the un-prefixed headers in srcs to work
# around the fact that zlib isn't consistent in its
# choice of <> or "" delimiter when including itself.
] _ZLIB_HEADERS,
hdrs = _ZLIB_PREFIXED_HEADERS,
copts = select({
"@bazel_tools//src/conditions:windows": [],
"//conditions:default": [
"-Wno-unused-variable",
"-Wno-implicit-function-declaration",
],
}),
includes = ["zlib/include/"],
visibility = ["//visibility:public"],
)
Add to your WORKSPACE:
load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
load("@bazel_tools//tools/build_defs/repo:utils.bzl", "maybe")
maybe(
http_archive,
name = "net_zlib_zlib",
build_file = "@openexr//:bazel/third_party/zlib.BUILD",
sha256 = "c3e5e9fdd5004dcb542feda5ee4f0ff0744628baf8ed2dd5d66f8ca1197cb1a1",
strip_prefix = "zlib-1.2.11",
urls = [
"https://zlib.net/zlib-1.2.11.tar.gz",
"https://mirror.bazel.build/zlib.net/zlib-1.2.11.tar.gz",
],
)
Add to the deps attribute of your cc_binary:
deps = [
"@net_zlib_zlib//:zlib",
],
Example: OpenEXR depends on zlib - see here