support for dynamic linking and PIE

bizviznavneet · Aug 8, 2016 · 41bf52a · 41bf52a
1 parent 7632264
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diff --git a/.gitignore b/.gitignore
@@ -3,3 +3,4 @@ tools/
 vendor/
 
 .vscode/
+.glide/
diff --git a/Documentation/build.md b/Documentation/build.md
@@ -0,0 +1,69 @@
+# Building
+
+Castle is golang binary that uses cgo to interface with embedded ceph. The ceph 
+project is a submodule of castle and is built from the top level Makefile.
+
+## Static binary
+
+This is the easiest option and produced static binaries for castled and tools. These
+binaries can easily be used inside minimal or scratch containers, or run on minimal
+linux distributions like CoreOS.
+
+```
+make STATIC=1 build
+```
+
+## Dyanmic binary
+
+If you dont want to distribute a static binary, a dynamically linked binary is 
+supported. The approach we take is to link most of the glibc binaries dynamically
+and the rest of the libraries continue to be linked statically. Ceph has a lot
+of dependencies and we take this approach to simplify the distribution.
+
+```
+make STATIC=0 build
+```
+
+## Hardedened binary (PIE)
+
+You can build a Position Independent executable as follows:
+
+```
+make STATIC=0 PIE=1 build
+```
+
+## Switching Allocators
+
+Using a different memory allocator can impact the overall performance of the system. 
+Three allocators are currently supported: jemalloc, tcmalloc and libc. To specify
+an allocator during the build run the following:
+
+```
+make ALLOCATOR=jemalloc build
+```
+
+## Debug Builds
+
+To build a binary with debug symbols run the following:
+
+```
+make DEBUG=1 build
+```
+
+Note the binary will be significantly larger in size.
+
+## Verbose Builds
+
+To turn on verbose build output run the following
+
+```
+make DEBUG=1 build
+```
+
+## Parallel Builds
+
+You can speed up the build significantly by passing the -j flag to make as follows:
+
+```
+make -j4 build
+```
diff --git a/Makefile b/Makefile
@@ -7,10 +7,12 @@ GOARCH = $(shell go env GOARCH)
 # TODO: support for tracing in ceph
 # TODO: jemalloc and static linking are currently broken due to https://github.com/jemalloc/jemalloc/issues/442
 # TODO: remove leveldb
+# TODO: can we strip -s all binaries?
 
 # Can be used for additional go build flags
 BUILDFLAGS ?=
 LDFLAGS ?=
+TAGS ?= 
 
 # Additional flags to use when calling cmake on ceph
 CEPHD_CMAKE += \
@@ -24,11 +26,26 @@ CEPHD_CMAKE += \
 	-DWITH_MANPAGE=OFF \
 	-DWITH_PROFILER=OFF
 
-# set to 1 for a completely static build
+# set to 1 for a completely static build. Otherwise if set to 0
+# a dynamic binary is produced that requires glibc to be installed
 STATIC ?= 1
 ifeq ($(STATIC),1)
-LDFLAGS += -extldflags "-static"
 BUILDFLAGS += -installsuffix cgo
+LDFLAGS += -extldflags "-static"
+TAGS += static
+else
+TAGS += dynamic
+endif
+
+# build a position independent executable. This implies dynamic linking
+# since statically-linked PIE is not supported by the linker/glibc
+PIE ?= 0
+ifeq ($(PIE),1)
+ifeq ($(STATIC),1)
+$(error PIE only supported with dynamic linking. Set STATIC=0.)
+endif
+BUILDFLAGS += -buildmode=pie
+TAGS += pie
 endif
 
 # Can be jemalloc, tcmalloc or glibc 
@@ -57,6 +74,9 @@ V ?= 0
 ifeq ($(V),1)
 LDFLAGS += -v
 BUILDFLAGS += -x
+MFLAGS += -w
+else
+MFLAGS += -s
 endif
 
 # set the version number. 
@@ -70,16 +90,16 @@ all: build test
 
 .PHONY: build
 build: vendor ceph
-	mkdir -p ceph/build
+	@mkdir -p ceph/build
 	@echo "##### configuring ceph" 
 	cd ceph/build && cmake $(CEPHD_CMAKE) ..
 	@echo "##### building ceph" 
 	cd ceph/build && $(MAKE) $(MFLAGS) cephd
 ifeq ($(DEBUG),0)
-	echo "##### stripping libcephd.a" 
+	@echo "##### stripping libcephd.a" 
 	strip -S ceph/build/lib/libcephd.a
 endif
-	echo "##### building castled" 
+	@echo "##### building castled" 
 	go build $(BUILDFLAGS) -tags '$(TAGS)' -ldflags '$(LDFLAGS)' -o bin/castled ./cmd/castled
 
 ceph:

diff --git a/ceph b/ceph
diff --git a/pkg/cephd/cephd.go b/pkg/cephd/cephd.go
@@ -1,11 +1,14 @@
 package cephd
 
 // #cgo CFLAGS: -I${SRCDIR}/../../ceph/src/include
-// #cgo jemalloc LDFLAGS: -ljemalloc
-// #cgo tcmalloc LDFLAGS: -ltcmalloc_minimal
-// #cgo LDFLAGS: -L${SRCDIR}/../../ceph/build/lib -lcephd -lm -ldl -lboost_system -lboost_thread -lboost_iostreams -lboost_random -lz -lsnappy -lcrypto++ -lresolv -lleveldb -laio -lblkid -luuid
+// #cgo jemalloc,static LDFLAGS: -ljemalloc
+// #cgo tcmalloc,static LDFLAGS: -ltcmalloc_minimal
+// #cgo jemalloc,dynamic LDFLAGS: -Wl,-Bstatic -ljemalloc -Wl,-Bdynamic
+// #cgo tcmalloc,dynamic LDFLAGS: -Wl,-Bstatic -ltcmalloc_minimal -Wl,-Bdynamic
 // #cgo jemalloc tcmalloc CFLAGS: -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-free
 // #cgo jemalloc tcmalloc CXXFLAGS: -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-free
+// #cgo static LDFLAGS: -L${SRCDIR}/../../ceph/build/lib -lcephd -lboost_system -lboost_thread -lboost_iostreams -lboost_random -lz -lsnappy -lcrypto++ -lleveldb -laio -lblkid -luuid -lm -ldl -lresolv
+// #cgo dynamic LDFLAGS: -L${SRCDIR}/../../ceph/build/lib -Wl,-Bstatic -lcephd -lboost_system -lboost_thread -lboost_iostreams -lboost_random -lz -lsnappy -lcrypto++ -lleveldb -laio -lblkid -luuid -Wl,-Bdynamic -ldl -lm -lresolv
 // #include <errno.h>
 // #include <stdlib.h>
 // #include <string.h>