mariadb: fix uClibc builds

mariadb 10.2.x depends on iconv. glibc and musl include iconv, uclibc
does not. So for uclibc builds a depend on libiconv-full is required.

Signed-off-by: Sebastian Kemper <sebastian_ml@gmx.net>

utils/mariadb/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=mariadb
 PKG_VERSION:=10.2.16
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
 PKG_SOURCE_URL := \
@@ -36,6 +36,7 @@ CMAKE_INSTALL:=1
 PLUGIN_DIR:=/usr/lib/mysql/plugin
 
 MARIADB_COMMON_DEPENDS := \
+	+USE_UCLIBC:libiconv-full \
 	+libatomic \
 	+libopenssl \
 	+libstdcpp \
@@ -384,6 +385,13 @@ CMAKE_OPTIONS += \
 	-DPLUGIN_AUTH_GSSAPI_CLIENT=NO \
 	-DPLUGIN_CRACKLIB_PASSWORD_CHECK=NO
 
+# musl and glibc include their own iconv, but uclibc does not
+ifneq ($(CONFIG_USE_UCLIBC),)
+CMAKE_OPTIONS += \
+	-DICONV_INCLUDE_DIR=$(STAGING_DIR)/usr/lib/libiconv-full/include \
+	-DICONV_LIBRARIES=$(STAGING_DIR)/usr/lib/libiconv-full/lib/libiconv.so
+endif
+
 CMAKE_OPTIONS += \
 	$(foreach p,$(MARIADB_SERVER_PLUGINS),-D$(plugin-$(p))=$(if $(CONFIG_PACKAGE_$(PKG_NAME)-server-plugin-$(subst _,-,$(p))),DYNAMIC,NO))
 
@@ -426,6 +434,20 @@ define Host/Install
 	$(INSTALL_DATA) $(HOST_BUILD_DIR)/import_executables.cmake $(1)/share/mariadb
 endef
 
+# LIBICONV_PLUG is used in GNU's libiconv for redefinition of exports [e.g.
+# from libiconv_open() to iconv_open()]. But in OpenWrt this variable is not set
+# when building libiconv-full. So when mariadb sets LIBICONV_PLUG it expects
+# iconv_open() to be available for example, which is not the case - only
+# libiconv_open() is. To address this do not set the variable when building
+# against libiconv-full.
+
+define Build/Prepare
+	$(call Build/Prepare/Default)
+ifneq ($(CONFIG_USE_UCLIBC),)
+	$(SED) '/ADD_DEFINITIONS(-DLIBICONV_PLUG)/d' $(PKG_BUILD_DIR)/libmariadb/libmariadb/CMakeLists.txt
+endif
+endef
+
 define Build/InstallDev
 	$(INSTALL_DIR) $(2)/bin $(1)/usr/bin $(1)/usr/include $(1)/usr/lib/mysql $(1)/usr/lib/pkgconfig $(1)/usr/share/aclocal
 	$(INSTALL_BIN) $(PKG_INSTALL_DIR)/usr/bin/mysql_config $(1)/usr/bin