deps: configure and build patched libedit

Teach our Makefile to orchestrate the configuration and building of our
line editing library, libedit. This allows us to incorporate an upstream
patch for cockroachdb#31843, which was causing incorrect spacing when recalling
multi-line history entries. Previously, we were attempting to link
against potentially outdated system libedits, which are likely to
exhibit the bug for years to come.

Release note (build change): a recent libedit is now bundled with
CockroachDB, which fixes some line editing bugs in the CockroachDB
console. On platforms that include libedit as part of the base system,
like macOS and FreeBSD, CockroachDB no longer links against the system
libedit.

.gitmodules

@@ -26,3 +26,6 @@
 [submodule "c-deps/krb5"]
 	path = c-deps/krb5
 	url = https://github.com/cockroachdb/krb5.git
+[submodule "c-deps/libedit"]
+	path = c-deps/libedit
+	url = https://github.com/cockroachdb/libedit.git

Makefile

@@ -410,6 +410,7 @@ JEMALLOC_SRC_DIR := $(C_DEPS_DIR)/jemalloc
 PROTOBUF_SRC_DIR := $(C_DEPS_DIR)/protobuf
 ROCKSDB_SRC_DIR  := $(C_DEPS_DIR)/rocksdb
 SNAPPY_SRC_DIR   := $(C_DEPS_DIR)/snappy
+LIBEDIT_SRC_DIR  := $(C_DEPS_DIR)/libedit
 LIBROACH_SRC_DIR := $(C_DEPS_DIR)/libroach
 KRB5_SRC_DIR     := $(C_DEPS_DIR)/krb5
 
@@ -436,6 +437,7 @@ JEMALLOC_DIR := $(BUILD_DIR)/jemalloc$(if $(use-msan),_msan)
 PROTOBUF_DIR := $(BUILD_DIR)/protobuf$(if $(use-msan),_msan)
 ROCKSDB_DIR  := $(BUILD_DIR)/rocksdb$(if $(use-msan),_msan)$(if $(use-stdmalloc),_stdmalloc)$(if $(USE_ROCKSDB_ASSERTIONS),_assert)
 SNAPPY_DIR   := $(BUILD_DIR)/snappy$(if $(use-msan),_msan)
+LIBEDIT_DIR  := $(BUILD_DIR)/libedit$(if $(use-msan),_msan)
 LIBROACH_DIR := $(BUILD_DIR)/libroach$(if $(use-msan),_msan)
 KRB5_DIR     := $(BUILD_DIR)/krb5$(if $(use-msan),_msan)
 # Can't share with protobuf because protoc is always built for the host.
@@ -446,12 +448,13 @@ LIBJEMALLOC := $(JEMALLOC_DIR)/lib/libjemalloc.a
 LIBPROTOBUF := $(PROTOBUF_DIR)/libprotobuf.a
 LIBROCKSDB  := $(ROCKSDB_DIR)/librocksdb.a
 LIBSNAPPY   := $(SNAPPY_DIR)/libsnappy.a
+LIBEDIT     := $(LIBEDIT_DIR)/src/.libs/libedit.a
 LIBROACH    := $(LIBROACH_DIR)/libroach.a
 LIBROACHCCL := $(LIBROACH_DIR)/libroachccl.a
 LIBKRB5     := $(KRB5_DIR)/lib/libgssapi_krb5.a
 PROTOC 		 := $(PROTOC_DIR)/protoc
 
-C_LIBS_COMMON = $(if $(use-stdmalloc),,$(LIBJEMALLOC)) $(LIBPROTOBUF) $(LIBSNAPPY) $(LIBROCKSDB)
+C_LIBS_COMMON = $(if $(use-stdmalloc),,$(LIBJEMALLOC)) $(LIBPROTOBUF) $(LIBSNAPPY) $(LIBEDIT) $(LIBROCKSDB)
 C_LIBS_OSS = $(C_LIBS_COMMON) $(LIBROACH)
 C_LIBS_CCL = $(C_LIBS_COMMON) $(LIBCRYPTOPP) $(LIBROACHCCL)
 
@@ -484,22 +487,39 @@ native-tag := $(subst -,_,$(TARGET_TRIPLE))$(if $(use-stdmalloc),_stdmalloc)$(if
 # constraint `{native-tag}` and are built the first time a Make-driven build
 # encounters a given native tag. These tags are unset when building with the Go
 # toolchain directly, so these files are only compiled when building with Make.
-CGO_PKGS := cli server/status storage/engine ccl/storageccl/engineccl ccl/gssapiccl
-CGO_UNSUFFIXED_FLAGS_FILES := $(addprefix ./pkg/,$(addsuffix /zcgo_flags.go,$(CGO_PKGS)))
-CGO_SUFFIXED_FLAGS_FILES   := $(addprefix ./pkg/,$(addsuffix /zcgo_flags_$(native-tag).go,$(CGO_PKGS)))
-CGO_FLAGS_FILES := $(CGO_UNSUFFIXED_FLAGS_FILES) $(CGO_SUFFIXED_FLAGS_FILES)
+CGO_PKGS := \
+	pkg/cli \
+	pkg/server/status \
+	pkg/storage/engine \
+	pkg/ccl/storageccl/engineccl \
+	pkg/ccl/gssapiccl \
+	vendor/github.com/knz/go-libedit/unix
+vendor/github.com/knz/go-libedit/unix-package := libedit_unix
+CGO_UNSUFFIXED_FLAGS_FILES := $(addprefix ./,$(addsuffix /zcgo_flags.go,$(CGO_PKGS)))
+CGO_SUFFIXED_FLAGS_FILES   := $(addprefix ./,$(addsuffix /zcgo_flags_$(native-tag).go,$(CGO_PKGS)))
+BASE_CGO_FLAGS_FILES := $(CGO_UNSUFFIXED_FLAGS_FILES) $(CGO_SUFFIXED_FLAGS_FILES)
+CGO_FLAGS_FILES := $(BASE_CGO_FLAGS_FILES) vendor/github.com/knz/go-libedit/unix/zcgo_flags_extra.go
 
 $(CGO_UNSUFFIXED_FLAGS_FILES): build/defs.mk.sig
 
-$(CGO_FLAGS_FILES): Makefile
+$(BASE_CGO_FLAGS_FILES): Makefile | bin/.submodules-initialized
 	@echo '// GENERATED FILE DO NOT EDIT' > $@
 	@echo >> $@
 	@echo '// +build $(if $(findstring $(native-tag),$@),$(native-tag),!make)' >> $@
 	@echo >> $@
-	@echo 'package $(notdir $(@D))' >> $@
+	@echo 'package $(if $($(@D)-package),$($(@D)-package),$(notdir $(@D)))' >> $@
 	@echo >> $@
-	@echo '// #cgo CPPFLAGS: $(addprefix -I,$(JEMALLOC_DIR)/include $(KRB_CPPFLAGS))' >> $@
-	@echo '// #cgo LDFLAGS: $(addprefix -L,$(CRYPTOPP_DIR) $(PROTOBUF_DIR) $(JEMALLOC_DIR)/lib $(SNAPPY_DIR) $(ROCKSDB_DIR) $(LIBROACH_DIR) $(KRB_DIR))' >> $@
+	@echo '// #cgo CPPFLAGS: $(addprefix -I,$(JEMALLOC_DIR)/include $(KRB_CPPFLAGS)) -DGO_LIBEDIT_NO_BUILD' >> $@
+	@echo '// #cgo LDFLAGS: $(addprefix -L,$(CRYPTOPP_DIR) $(PROTOBUF_DIR) $(JEMALLOC_DIR)/lib $(SNAPPY_DIR) $(LIBEDIT_DIR)/src/.libs $(ROCKSDB_DIR) $(LIBROACH_DIR) $(KRB_DIR))' >> $@
+	@echo 'import "C"' >> $@
+
+vendor/github.com/knz/go-libedit/unix/zcgo_flags_extra.go: Makefile | bin/.submodules-initialized
+	@echo '// GENERATED FILE DO NOT EDIT' > $@
+	@echo >> $@
+	@echo 'package $($(@D)-package)' >> $@
+	@echo >> $@
+	@echo '// #cgo CPPFLAGS: -DGO_LIBEDIT_NO_BUILD' >> $@
+	@echo '// #cgo LDFLAGS: -ledit -lncurses' >> $@
 	@echo 'import "C"' >> $@
 
 # BUILD ARTIFACT CACHING
@@ -602,6 +622,18 @@ $(SNAPPY_DIR)/Makefile: $(C_DEPS_DIR)/snappy-rebuild | bin/.submodules-initializ
 	cd $(SNAPPY_DIR) && cmake $(xcmake-flags) $(SNAPPY_SRC_DIR) \
 	  -DCMAKE_BUILD_TYPE=Release
 
+$(LIBEDIT_SRC_DIR)/configure.ac: | bin/.submodules-initialized
+
+$(LIBEDIT_SRC_DIR)/configure: $(LIBEDIT_SRC_DIR)/configure.ac
+	cd $(LIBEDIT_SRC_DIR) && autoconf
+
+$(LIBEDIT_DIR)/Makefile: $(C_DEPS_DIR)/libedit-rebuild $(LIBEDIT_SRC_DIR)/configure
+	rm -rf $(LIBEDIT_DIR)
+	mkdir -p $(LIBEDIT_DIR)
+	@# NOTE: If you change the configure flags below, bump the version in
+	@# $(C_DEPS_DIR)/libedit-rebuild. See above for rationale.
+	cd $(LIBEDIT_DIR) && $(LIBEDIT_SRC_DIR)/configure $(xconfigure-flags) --disable-examples --disable-shared
+
 # TODO(benesch): make it possible to build libroach without CCL code. Because
 # libroach and libroachccl are defined in the same CMake project, CMake requires
 # that the CCL code be present even if only the OSS target will be built.
@@ -660,6 +692,9 @@ $(LIBPROTOBUF): $(PROTOBUF_DIR)/Makefile bin/uptodate .ALWAYS_REBUILD
 $(LIBSNAPPY): $(SNAPPY_DIR)/Makefile bin/uptodate .ALWAYS_REBUILD
 	@uptodate $@ $(SNAPPY_SRC_DIR) || $(MAKE) --no-print-directory -C $(SNAPPY_DIR) snappy
 
+$(LIBEDIT): $(LIBEDIT_DIR)/Makefile bin/uptodate .ALWAYS_REBUILD
+	@uptodate $@ $(LIBEDIT_SRC_DIR) || $(MAKE) --no-print-directory -C $(LIBEDIT_DIR)/src
+
 $(LIBROCKSDB): $(ROCKSDB_DIR)/Makefile bin/uptodate .ALWAYS_REBUILD
 	@uptodate $@ $(ROCKSDB_SRC_DIR) || $(MAKE) --no-print-directory -C $(ROCKSDB_DIR) rocksdb
 
@@ -678,6 +713,7 @@ $(LIBKRB5): $(KRB5_DIR)/Makefile bin/uptodate .ALWAYS_REBUILD
 .PHONY: protoc libcryptopp libjemalloc libprotobuf libsnappy librocksdb libroach libroachccl libkrb5
 protoc:      $(PROTOC)
 libcryptopp: $(LIBCRYPTOPP)
+libedit:     $(LIBEDIT)
 libjemalloc: $(LIBJEMALLOC)
 libprotobuf: $(LIBPROTOBUF)
 libsnappy:   $(LIBSNAPPY)

build/variables.mk

@@ -5,6 +5,7 @@ define VALID_VARS
   ARCHIVE
   ARCHIVE_BASE
   ARCHIVE_EXTRAS
+  BASE_CGO_FLAGS_FILES
   BENCHES
   BENCHTIMEOUT
   BUILDCHANNEL
@@ -83,6 +84,9 @@ define VALID_VARS
   LC_ALL
   LDFLAGS
   LIBCRYPTOPP
+  LIBEDIT
+  LIBEDIT_DIR
+  LIBEDIT_SRC_DIR
   LIBJEMALLOC
   LIBPROTOBUF
   LIBROACH

c-deps/libedit-rebuild

@@ -0,0 +1,4 @@
+Bump the version below when changing libedit configure flags. Search for "BUILD
+ARTIFACT CACHING" in the top-level Makefile for rationale.
+
+1