pkg/proc: add build scripts & docker image for ebpf (go-delve#2847)

Adds a few build scripts and a container image for reproducible builds
of the ebpf programs.

Makefile

@@ -1,5 +1,6 @@
 .DEFAULT_GOAL=test
 
+SHELL := /bin/bash
 GO_SRC := $(shell find . -type f -not -path './_fixtures/*' -not -path './vendor/*' -not -path './_scripts/*' -not -path './localtests/*' -name '*.go')
 
 check-cert:
@@ -29,4 +30,10 @@ test-integration-run:
 vendor:
 	@go run _scripts/make.go vendor
 
-.PHONY: vendor test-integration-run test-proc-run test check-cert install build vet uninstall
+build-ebpf-image:
+	./pkg/proc/internal/ebpf/build/build-ebpf-builder-img.sh
+
+build-ebpf-object: build-ebpf-image
+	./pkg/proc/internal/ebpf/build/build-ebpf-objects.sh
+
+.PHONY: vendor test-integration-run test-proc-run test check-cert install build vet uninstall build-ebpf-image build-ebpf-object

cmd/dlv/dlv_test.go

@@ -208,7 +208,6 @@ func getDlvBin(t *testing.T) (string, string) {
 }
 
 func getDlvBinEBPF(t *testing.T) (string, string) {
-	os.Setenv("CGO_LDFLAGS", "/usr/lib/libbpf.a")
 	return getDlvBinInternal(t, "-tags", "ebpf")
 }
 

pkg/proc/internal/ebpf/build/build-ebpf-builder-img.sh

@@ -0,0 +1,5 @@
+#!/bin/bash -e
+
+sudo docker build \
+    -t delve-ebpf-builder:v0.0.1 \
+    -f pkg/proc/internal/ebpf/build/ebpf-Dockerfile ./pkg/proc/internal/ebpf/build

pkg/proc/internal/ebpf/build/build-ebpf-objects.sh

@@ -0,0 +1,17 @@
+#!/bin/bash -e
+
+# The go generate command seems to not like being run from
+# the vendor directory. Remove it and restore it after.
+rm -rf vendor
+
+restore_vendor() {
+  git checkout vendor
+}
+
+trap restore_vendor EXIT
+
+docker run \
+    -it \
+    --rm \
+    -v "$(pwd)":/delve-bpf \
+    delve-ebpf-builder:v0.0.1

pkg/proc/internal/ebpf/build/ebpf-Dockerfile

@@ -0,0 +1,19 @@
+FROM ubuntu:21.04
+
+ENV DEBIAN_FRONTEND noninteractive
+RUN apt-get update && apt-get install -y \
+    build-essential \
+    gcc-multilib \
+    git \
+    wget \
+    clang \
+    linux-headers-5.11.0-40 \
+    libbpf-dev
+
+RUN wget https://golang.org/dl/go1.17.3.linux-amd64.tar.gz
+RUN tar -C /usr/local -xzf go1.17.3.linux-amd64.tar.gz
+RUN cp /usr/local/go/bin/go /usr/bin/go
+
+WORKDIR /delve-bpf/pkg/proc/internal/ebpf/
+
+CMD [ "go", "generate", "./..." ]