From 517ffa07b435b311bb48a23c209258d31c523b5f Mon Sep 17 00:00:00 2001
From: Marco Mariani <marco@crowdsec.net>
Date: Tue, 23 May 2023 22:49:29 +0200
Subject: [PATCH 1/6] build against libre2-dev if found

---
 Makefile | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index 334e738c8ce..f4fc765741e 100644
--- a/Makefile
+++ b/Makefile
@@ -39,7 +39,7 @@ $(warning WARNING: The BUILD_STATIC variable is deprecated and has no effect. Bu
 endif
 
 export LD_OPTS=-ldflags "-s -w -extldflags '-static' $(LD_OPTS_VARS)" \
-	-trimpath -tags netgo,osusergo,sqlite_omit_load_extension
+	-trimpath -tags netgo,osusergo,sqlite_omit_load_extension$(RE2_TAG)
 
 ifneq (,$(TEST_COVERAGE))
 LD_OPTS += -cover
@@ -76,6 +76,13 @@ clean: testclean
 	@$(RM) ./$(EMAIL_PLUGIN_FOLDER)/$(EMAIL_PLUGIN_BIN) $(WIN_IGNORE_ERR)
 	@$(RM) ./$(DUMMY_PLUGIN_FOLDER)/$(DUMMY_PLUGIN_BIN) $(WIN_IGNORE_ERR)
 
+RE2_TAG := $(shell echo "int main() { return 0; }" | $(CC) -x c - -o /dev/null -lre2 >/dev/null 2>&1 && echo ,re2_cgo)
+
+ifneq (,$(RE2_TAG))
+$(info Using C++ regexp library)
+else
+$(info Using WebAssembly regexp library)
+endif
 
 cscli: goversion
 	@$(MAKE) -C $(CSCLI_FOLDER) build $(MAKE_FLAGS)

From abc65977fdf42a20fc28acd069b07629f2bd5dd1 Mon Sep 17 00:00:00 2001
From: Marco Mariani <marco@crowdsec.net>
Date: Fri, 2 Jun 2023 14:35:30 +0200
Subject: [PATCH 2/6] moved stuff in the makefile, make it possible to choose
 c++ or wasm

---
 Makefile | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/Makefile b/Makefile
index f4fc765741e..917e21d1b5a 100644
--- a/Makefile
+++ b/Makefile
@@ -38,6 +38,16 @@ ifdef BUILD_STATIC
 $(warning WARNING: The BUILD_STATIC variable is deprecated and has no effect. Builds are static by default since v1.5.0.)
 endif
 
+# override with "make RE2_TAG=" to use the WebAssembly regexp library
+# override with "make RE2_TAG=,re2_cgo" to use the C++ regexp library
+RE2_TAG ?= $(shell echo "int main() { return 0; }" | $(CC) -x c - -o /dev/null -lre2 >/dev/null 2>&1 && echo ,re2_cgo)
+
+ifneq (,$(RE2_TAG))
+$(info Using C++ regexp library)
+else
+$(info Using WebAssembly regexp library)
+endif
+
 export LD_OPTS=-ldflags "-s -w -extldflags '-static' $(LD_OPTS_VARS)" \
 	-trimpath -tags netgo,osusergo,sqlite_omit_load_extension$(RE2_TAG)
 
@@ -76,14 +86,6 @@ clean: testclean
 	@$(RM) ./$(EMAIL_PLUGIN_FOLDER)/$(EMAIL_PLUGIN_BIN) $(WIN_IGNORE_ERR)
 	@$(RM) ./$(DUMMY_PLUGIN_FOLDER)/$(DUMMY_PLUGIN_BIN) $(WIN_IGNORE_ERR)
 
-RE2_TAG := $(shell echo "int main() { return 0; }" | $(CC) -x c - -o /dev/null -lre2 >/dev/null 2>&1 && echo ,re2_cgo)
-
-ifneq (,$(RE2_TAG))
-$(info Using C++ regexp library)
-else
-$(info Using WebAssembly regexp library)
-endif
-
 cscli: goversion
 	@$(MAKE) -C $(CSCLI_FOLDER) build $(MAKE_FLAGS)
 

From c132d5c07acdd2d70b03b36cd7558bdbdfd0e0f0 Mon Sep 17 00:00:00 2001
From: Marco Mariani <marco@crowdsec.net>
Date: Fri, 2 Jun 2023 15:27:32 +0200
Subject: [PATCH 3/6] use wasm by default in windows, override with RE2_TAG

---
 Makefile                   | 6 +-----
 mk/platform/unix_common.mk | 4 ++++
 mk/platform/windows.mk     | 4 ++++
 3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/Makefile b/Makefile
index 917e21d1b5a..df2895b1680 100644
--- a/Makefile
+++ b/Makefile
@@ -38,10 +38,6 @@ ifdef BUILD_STATIC
 $(warning WARNING: The BUILD_STATIC variable is deprecated and has no effect. Builds are static by default since v1.5.0.)
 endif
 
-# override with "make RE2_TAG=" to use the WebAssembly regexp library
-# override with "make RE2_TAG=,re2_cgo" to use the C++ regexp library
-RE2_TAG ?= $(shell echo "int main() { return 0; }" | $(CC) -x c - -o /dev/null -lre2 >/dev/null 2>&1 && echo ,re2_cgo)
-
 ifneq (,$(RE2_TAG))
 $(info Using C++ regexp library)
 else
@@ -49,7 +45,7 @@ $(info Using WebAssembly regexp library)
 endif
 
 export LD_OPTS=-ldflags "-s -w -extldflags '-static' $(LD_OPTS_VARS)" \
-	-trimpath -tags netgo,osusergo,sqlite_omit_load_extension$(RE2_TAG)
+	-trimpath -tags netgo,osusergo,sqlite_omit_load_extension$(addprefix ,$(RE2_TAG))
 
 ifneq (,$(TEST_COVERAGE))
 LD_OPTS += -cover
diff --git a/mk/platform/unix_common.mk b/mk/platform/unix_common.mk
index f611693f48b..e0456da7d15 100644
--- a/mk/platform/unix_common.mk
+++ b/mk/platform/unix_common.mk
@@ -12,3 +12,7 @@ BUILD_VERSION?=$(shell git describe --tags)
 BUILD_TIMESTAMP=$(shell date +%F"_"%T)
 DEFAULT_CONFIGDIR?=/etc/crowdsec
 DEFAULT_DATADIR?=/var/lib/crowdsec/data
+
+# override with "make RE2_TAG=" to use the WebAssembly regexp library
+# override with "make RE2_TAG=re2_cgo" to use the C++ regexp library
+RE2_TAG ?= $(shell echo "int main() { return 0; }" | $(CC) -x c - -o /dev/null -lre2 >/dev/null 2>&1 && echo re2_cgo)
diff --git a/mk/platform/windows.mk b/mk/platform/windows.mk
index e4c5e8a1234..0e984c80b9a 100644
--- a/mk/platform/windows.mk
+++ b/mk/platform/windows.mk
@@ -19,4 +19,8 @@ CPR=Copy-Item -Recurse
 MKDIR=New-Item -ItemType directory
 WIN_IGNORE_ERR=; exit 0
 
+# Link to the C++ re2 library with "make RE2_TAG=re2_cgo"
+# or webassembly by default
+RE2_TAG ?=
+
 $(info Building for windows)

From 531a426e89f2c47aba5ec35f3e82ab00b4b56fd8 Mon Sep 17 00:00:00 2001
From: Marco Mariani <marco@crowdsec.net>
Date: Tue, 6 Jun 2023 09:11:54 +0200
Subject: [PATCH 4/6] fix addprefix with comma

---
 Makefile | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index df2895b1680..048e912d760 100644
--- a/Makefile
+++ b/Makefile
@@ -44,8 +44,10 @@ else
 $(info Using WebAssembly regexp library)
 endif
 
+COMMA=,
+
 export LD_OPTS=-ldflags "-s -w -extldflags '-static' $(LD_OPTS_VARS)" \
-	-trimpath -tags netgo,osusergo,sqlite_omit_load_extension$(addprefix ,$(RE2_TAG))
+	-trimpath -tags netgo,osusergo,sqlite_omit_load_extension$(addprefix $(COMMA),$(RE2_TAG))
 
 ifneq (,$(TEST_COVERAGE))
 LD_OPTS += -cover

From 84bfb9962e6f2c5cc04ab4f135d2a91604a36de5 Mon Sep 17 00:00:00 2001
From: Marco Mariani <marco@crowdsec.net>
Date: Tue, 6 Jun 2023 11:40:49 +0200
Subject: [PATCH 5/6] Detect re2 with pkg-config, add Libre2 variable to
 cwversion

---
 Makefile                   | 51 +++++++++++++++++++++++++-------------
 mk/platform/unix_common.mk |  4 ---
 mk/platform/windows.mk     |  4 ---
 pkg/cwversion/version.go   |  2 ++
 4 files changed, 36 insertions(+), 25 deletions(-)

diff --git a/Makefile b/Makefile
index 82647be6a4c..d6f1b95f237 100644
--- a/Makefile
+++ b/Makefile
@@ -3,6 +3,9 @@ include mk/platform.mk
 BUILD_REQUIRE_GO_MAJOR ?= 1
 BUILD_REQUIRE_GO_MINOR ?= 20
 
+GOCMD = go
+GOTEST = $(GOCMD) test
+
 BUILD_CODENAME ?= alphaga
 
 CROWDSEC_FOLDER = ./cmd/crowdsec
@@ -14,8 +17,21 @@ PLUGINS_DIR = ./plugins/notifications
 CROWDSEC_BIN = crowdsec$(EXT)
 CSCLI_BIN = cscli$(EXT)
 
+# Directory for the release files
+RELDIR = crowdsec-$(BUILD_VERSION)
+
 GO_MODULE_NAME = github.com/crowdsecurity/crowdsec
 
+# see if we have libre2-dev installed for C++ optimizations
+RE2_CHECK := $(shell pkg-config --libs re2 2>/dev/null)
+
+#--------------------------------------
+#
+# Define MAKE_FLAGS and LD_OPTS for the sub-makefiles in cmd/ and plugins/
+#
+
+MAKE_FLAGS = --no-print-directory GOARCH=$(GOARCH) GOOS=$(GOOS) RM="$(RM)" WIN_IGNORE_ERR="$(WIN_IGNORE_ERR)" CP="$(CP)" CPR="$(CPR)" MKDIR="$(MKDIR)"
+
 LD_OPTS_VARS= \
 -X 'github.com/crowdsecurity/go-cs-lib/pkg/version.Version=$(BUILD_VERSION)' \
 -X 'github.com/crowdsecurity/go-cs-lib/pkg/version.BuildDate=$(BUILD_TIMESTAMP)' \
@@ -28,38 +44,37 @@ ifneq (,$(DOCKER_BUILD))
 LD_OPTS_VARS += -X '$(GO_MODULE_NAME)/pkg/cwversion.System=docker'
 endif
 
-ifdef BUILD_STATIC
-$(warning WARNING: The BUILD_STATIC variable is deprecated and has no effect. Builds are static by default since v1.5.0.)
-endif
+GO_TAGS := netgo,osusergo,sqlite_omit_load_extension
 
-ifneq (,$(RE2_TAG))
-$(info Using C++ regexp library)
-else
-$(info Using WebAssembly regexp library)
+ifneq (,$(RE2_CHECK))
+# += adds a space that we don't want
+GO_TAGS := $(GO_TAGS),re2_cgo
+LD_OPTS_VARS += -X '$(GO_MODULE_NAME)/pkg/cwversion.Libre2=C++'
 endif
 
-COMMA=,
-
 export LD_OPTS=-ldflags "-s -w -extldflags '-static' $(LD_OPTS_VARS)" \
-	-trimpath -tags netgo,osusergo,sqlite_omit_load_extension$(addprefix $(COMMA),$(RE2_TAG))
+	-trimpath -tags $(GO_TAGS)
 
 ifneq (,$(TEST_COVERAGE))
 LD_OPTS += -cover
 endif
 
-GOCMD = go
-GOTEST = $(GOCMD) test
-
-RELDIR = crowdsec-$(BUILD_VERSION)
-
-# flags for sub-makefiles
-MAKE_FLAGS = --no-print-directory GOARCH=$(GOARCH) GOOS=$(GOOS) RM="$(RM)" WIN_IGNORE_ERR="$(WIN_IGNORE_ERR)" CP="$(CP)" CPR="$(CPR)" MKDIR="$(MKDIR)"
+#--------------------------------------
 
 .PHONY: build
 build: pre-build goversion crowdsec cscli plugins
 
+.PHONY: pre-build
 pre-build:
+ifdef BUILD_STATIC
+	$(warning WARNING: The BUILD_STATIC variable is deprecated and has no effect. Builds are static by default since v1.5.0.)
+endif
 	$(info Building $(BUILD_VERSION) ($(BUILD_TAG)) for $(GOOS)/$(GOARCH))
+ifneq (,$(RE2_CHECK))
+	$(info Using C++ regexp library)
+else
+	$(info Fallback to WebAssembly regexp library. To use the C++ version, make sure you have installed libre2-dev and pkg-config.)
+endif
 	$(info )
 
 .PHONY: all
@@ -83,9 +98,11 @@ clean: testclean
 		$(MAKE) -C $(PLUGINS_DIR)/$(plugin) clean $(MAKE_FLAGS); \
 	)
 
+.PHONY: cscli
 cscli: goversion
 	@$(MAKE) -C $(CSCLI_FOLDER) build $(MAKE_FLAGS)
 
+.PHONY: crowdsec
 crowdsec: goversion
 	@$(MAKE) -C $(CROWDSEC_FOLDER) build $(MAKE_FLAGS)
 
diff --git a/mk/platform/unix_common.mk b/mk/platform/unix_common.mk
index e0456da7d15..f611693f48b 100644
--- a/mk/platform/unix_common.mk
+++ b/mk/platform/unix_common.mk
@@ -12,7 +12,3 @@ BUILD_VERSION?=$(shell git describe --tags)
 BUILD_TIMESTAMP=$(shell date +%F"_"%T)
 DEFAULT_CONFIGDIR?=/etc/crowdsec
 DEFAULT_DATADIR?=/var/lib/crowdsec/data
-
-# override with "make RE2_TAG=" to use the WebAssembly regexp library
-# override with "make RE2_TAG=re2_cgo" to use the C++ regexp library
-RE2_TAG ?= $(shell echo "int main() { return 0; }" | $(CC) -x c - -o /dev/null -lre2 >/dev/null 2>&1 && echo re2_cgo)
diff --git a/mk/platform/windows.mk b/mk/platform/windows.mk
index a617cf34df1..8e2cdf19b40 100644
--- a/mk/platform/windows.mk
+++ b/mk/platform/windows.mk
@@ -18,7 +18,3 @@ CP=Copy-Item
 CPR=Copy-Item -Recurse
 MKDIR=New-Item -ItemType directory
 WIN_IGNORE_ERR=; exit 0
-
-# Link to the C++ re2 library with "make RE2_TAG=re2_cgo"
-# or webassembly by default
-RE2_TAG ?=
diff --git a/pkg/cwversion/version.go b/pkg/cwversion/version.go
index f910159fa9e..aeac6f2f22c 100644
--- a/pkg/cwversion/version.go
+++ b/pkg/cwversion/version.go
@@ -20,6 +20,7 @@ var (
 	Constraint_scenario = ">= 1.0, < 3.0"
 	Constraint_api      = "v1"
 	Constraint_acquis   = ">= 1.0, < 2.0"
+	Libre2              = "WebAssembly"
 )
 
 func ShowStr() string {
@@ -38,6 +39,7 @@ func Show() {
 	log.Printf("BuildDate: %s", version.BuildDate)
 	log.Printf("GoVersion: %s", version.GoVersion)
 	log.Printf("Platform: %s\n", System)
+	log.Printf("libre2: %s\n", Libre2)
 	log.Printf("Constraint_parser: %s", Constraint_parser)
 	log.Printf("Constraint_scenario: %s", Constraint_scenario)
 	log.Printf("Constraint_api: %s", Constraint_api)

From 3c2e3b24479cec9fccd76df63f27db3afad61e10 Mon Sep 17 00:00:00 2001
From: Marco Mariani <marco@crowdsec.net>
Date: Tue, 6 Jun 2023 12:35:03 +0200
Subject: [PATCH 6/6] re2 for the docker version

---
 Dockerfile        | 12 +++++++++++-
 Dockerfile.debian |  2 +-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/Dockerfile b/Dockerfile
index b3b958896b2..da1c3ab06a9 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -7,9 +7,19 @@ WORKDIR /go/src/crowdsec
 
 COPY . .
 
+# Alpine does not ship a static version of re2, we can build it ourselves
+# Later versions require 'abseil', which is likewise not available in its static form
+ENV RE2_VERSION=2023-03-01
+
 # wizard.sh requires GNU coreutils
-RUN apk add --no-cache git gcc libc-dev make bash gettext binutils-gold coreutils && \
+RUN apk add --no-cache git g++ gcc libc-dev make bash gettext binutils-gold coreutils icu-static re2-dev pkgconfig && \
+    wget https://github.com/google/re2/archive/refs/tags/${RE2_VERSION}.tar.gz && \
+    tar -xzf ${RE2_VERSION}.tar.gz && \
+    cd re2-${RE2_VERSION} && \
+    make && \
+    make install && \
     echo "githubciXXXXXXXXXXXXXXXXXXXXXXXX" > /etc/machine-id && \
+    cd - && \
     make clean release DOCKER_BUILD=1 && \
     cd crowdsec-v* && \
     ./wizard.sh --docker-mode && \
diff --git a/Dockerfile.debian b/Dockerfile.debian
index b4cc4c9ec1a..10b06befdf0 100644
--- a/Dockerfile.debian
+++ b/Dockerfile.debian
@@ -12,7 +12,7 @@ ENV DEBCONF_NOWARNINGS="yes"
 
 # wizard.sh requires GNU coreutils
 RUN apt-get update && \
-    apt-get install -y -q git gcc libc-dev make bash gettext binutils-gold coreutils tzdata && \
+    apt-get install -y -q git gcc libc-dev make bash gettext binutils-gold coreutils tzdata libre2-dev && \
     echo "githubciXXXXXXXXXXXXXXXXXXXXXXXX" > /etc/machine-id && \
     make clean release DOCKER_BUILD=1 && \
     cd crowdsec-v* && \