From 8b14e7a540c5a6228130f8e8be98d573e8bc49a4 Mon Sep 17 00:00:00 2001 From: Tom Lundell Date: Fri, 12 Jun 2020 22:10:46 -0400 Subject: [PATCH] Remove msys dependency for Windows. Bazel genrules require a msys shell to execute shell commands. Replace the genrules with a simple C++ regex replacement binary. Fixes #303. --- bazel/expanded_template/BUILD | 5 ++ bazel/expanded_template/expand_template.cc | 62 +++++++++++++++++++ bazel/expanded_template/expanded_template.bzl | 35 +++++++++++ bazel/gflags.bzl | 55 ++++++++-------- 4 files changed, 131 insertions(+), 26 deletions(-) create mode 100644 bazel/expanded_template/BUILD create mode 100644 bazel/expanded_template/expand_template.cc create mode 100644 bazel/expanded_template/expanded_template.bzl diff --git a/bazel/expanded_template/BUILD b/bazel/expanded_template/BUILD new file mode 100644 index 0000000..e9b6504 --- /dev/null +++ b/bazel/expanded_template/BUILD @@ -0,0 +1,5 @@ +cc_binary( + name = "expand_template", + srcs = ["expand_template.cc"], + visibility = ["//visibility:public"], +) diff --git a/bazel/expanded_template/expand_template.cc b/bazel/expanded_template/expand_template.cc new file mode 100644 index 0000000..3eb2db6 --- /dev/null +++ b/bazel/expanded_template/expand_template.cc @@ -0,0 +1,62 @@ +#include +#include +#include +#include +#include + +struct Substitution { + std::basic_regex regex; + std::string replacement; +}; + +// Simple app that does a regex search-and-replace on a template +// and outputs the result. +// +// To invoke: +// expand_template +// --template PATH +// --output PATH +// regex0;replacement0 +// regex1;replacement1 +// ... +// +// Since it's only used as a private implementation detail of a rule and not +// user invoked we don't bother with error checking. +int main(int argc, const char** argv) { + // Parse args. + const char* template_path = nullptr; + const char* output_path = nullptr; + std::vector substitutions; + for (int i = 1; i < argc; ++i) { + const char* arg = argv[i]; + if (strcmp(arg, "--template") == 0) { + template_path = argv[++i]; + } else if (strcmp(arg, "--output") == 0) { + output_path = argv[++i]; + } else { + const char* mid = strchr(arg, ';'); + if (mid != nullptr) { + substitutions.push_back(Substitution{ + std::basic_regex(arg, mid - arg), + std::string(mid + 1), + }); + } + } + } + + // Read template. + std::ifstream ifs(template_path); + std::string str(std::istreambuf_iterator(ifs), + (std::istreambuf_iterator())); + + // Apply regexes. + for (const auto& subst : substitutions) { + str = std::regex_replace(str, subst.regex, subst.replacement); + } + + // Output file. + std::ofstream file(output_path); + file << str; + + return 0; +} diff --git a/bazel/expanded_template/expanded_template.bzl b/bazel/expanded_template/expanded_template.bzl new file mode 100644 index 0000000..ac17f59 --- /dev/null +++ b/bazel/expanded_template/expanded_template.bzl @@ -0,0 +1,35 @@ +def _impl(ctx): + args = ctx.actions.args() + args.add("--template", ctx.file.template) + args.add("--output", ctx.outputs.out) + args.add_all([k + ';' + v for k, v in ctx.attr.substitutions.items()]) + ctx.actions.run( + executable = ctx.executable._bin, + arguments = [args], + inputs = [ctx.file.template], + outputs = [ctx.outputs.out], + ) + return [ + DefaultInfo( + files = depset(direct = [ctx.outputs.out]), + runfiles = ctx.runfiles(files = [ctx.outputs.out]), + ), + ] + +expanded_template = rule( + implementation = _impl, + attrs = { + "out": attr.output(mandatory = True), + "template": attr.label( + allow_single_file = True, + mandatory = True, + ), + "substitutions": attr.string_dict(), + "_bin": attr.label( + default = "//bazel/expanded_template:expand_template", + executable = True, + allow_single_file = True, + cfg = "host", + ), + }, +) diff --git a/bazel/gflags.bzl b/bazel/gflags.bzl index 533fd61..5183f84 100644 --- a/bazel/gflags.bzl +++ b/bazel/gflags.bzl @@ -1,43 +1,46 @@ +load("//bazel/expanded_template:expanded_template.bzl", "expanded_template") # ------------------------------------------------------------------------------ # Add native rules to configure source files def gflags_sources(namespace=["google", "gflags"]): - native.genrule( + expanded_template( name = "gflags_declare_h", - srcs = ["src/gflags_declare.h.in"], - outs = ["gflags_declare.h"], - cmd = ("awk '{ " + - "gsub(/@GFLAGS_NAMESPACE@/, \"" + namespace[0] + "\"); " + - "gsub(/@(HAVE_STDINT_H|HAVE_SYS_TYPES_H|HAVE_INTTYPES_H|GFLAGS_INTTYPES_FORMAT_C99)@/, \"1\"); " + - "gsub(/@([A-Z0-9_]+)@/, \"0\"); " + - "print; }' $(<) > $(@)") + template = "src/gflags_declare.h.in", + out = "gflags_declare.h", + substitutions = { + "@GFLAGS_NAMESPACE@": namespace[0], + "@(HAVE_STDINT_H|HAVE_SYS_TYPES_H|HAVE_INTTYPES_H|GFLAGS_INTTYPES_FORMAT_C99)@": "1", + "@([A-Z0-9_]+)@": "0", + }, ) gflags_ns_h_files = [] for ns in namespace[1:]: gflags_ns_h_file = "gflags_{}.h".format(ns) - native.genrule( + expanded_template( name = gflags_ns_h_file.replace('.', '_'), - srcs = ["src/gflags_ns.h.in"], - outs = [gflags_ns_h_file], - cmd = ("awk '{ " + - "gsub(/@ns@/, \"" + ns + "\"); " + - "gsub(/@NS@/, \"" + ns.upper() + "\"); " + - "print; }' $(<) > $(@)") + template = "src/gflags_ns.h.in", + out = gflags_ns_h_file, + substitutions = { + "@ns@": ns, + "@NS@": ns.upper(), + } ) gflags_ns_h_files.append(gflags_ns_h_file) - native.genrule( + expanded_template( name = "gflags_h", - srcs = ["src/gflags.h.in"], - outs = ["gflags.h"], - cmd = ("awk '{ " + - "gsub(/@GFLAGS_ATTRIBUTE_UNUSED@/, \"\"); " + - "gsub(/@INCLUDE_GFLAGS_NS_H@/, \"" + '\n'.join(["#include \\\"gflags/{}\\\"".format(hdr) for hdr in gflags_ns_h_files]) + "\"); " + - "print; }' $(<) > $(@)") + template = "src/gflags.h.in", + out = "gflags.h", + substitutions = { + "@GFLAGS_ATTRIBUTE_UNUSED@": "", + "@INCLUDE_GFLAGS_NS_H@": '\n'.join(["#include \"gflags/{}\"".format(hdr) for hdr in gflags_ns_h_files]), + }, ) - native.genrule( + expanded_template( name = "gflags_completions_h", - srcs = ["src/gflags_completions.h.in"], - outs = ["gflags_completions.h"], - cmd = "awk '{ gsub(/@GFLAGS_NAMESPACE@/, \"" + namespace[0] + "\"); print; }' $(<) > $(@)" + template = "src/gflags_completions.h.in", + out = "gflags_completions.h", + substitutions = { + "@GFLAGS_NAMESPACE@": namespace[0], + }, ) hdrs = [":gflags_h", ":gflags_declare_h", ":gflags_completions_h"] hdrs.extend([':' + hdr.replace('.', '_') for hdr in gflags_ns_h_files])