configure: Check common include subdirectories for bdb headers, and refuse to use any version other than 4.8 by default

configure.ac

@@ -128,6 +128,7 @@ dnl Checks for programs.
 AC_PROG_CXX
 AC_PROG_CC
 AC_PROG_CPP
+AC_PROG_CXXCPP
 AC_PROG_INSTALL
 AC_PROG_OBJC
 m4_ifdef([AC_PROG_OBJCXX],[AC_PROG_OBJCXX])
@@ -334,8 +335,7 @@ AC_TRY_COMPILE([#include <sys/socket.h>],
 )
 
 dnl Check for libdb_cxx
-AC_CHECK_HEADER([db_cxx.h],,AC_MSG_ERROR(libdb_cxx headers missing))
-AC_CHECK_LIB([db_cxx], [main],, AC_MSG_ERROR(libdb_cxx missing))
+BITCOIN_FIND_BDB48
 
 dnl Check for libminiupnpc (optional)
 if test x$use_upnp != xno; then

src/Makefile.am

@@ -47,6 +47,9 @@ bitcoind_LDADD = libbitcoin.a leveldb/libleveldb.a leveldb/libmemenv.a \
 bitcoind_SOURCES = bitcoind.cpp
 #
 
+AM_CPPFLAGS += $(BDB_CPPFLAGS)
+bitcoind_LDADD += $(BDB_LIBS)
+
 leveldb/libleveldb.a:
 	@echo "Building LevelDB ..." && cd leveldb && CXX="$(CXX)" CC="$(CC)" \
 	  PLATFORM=$(TARGET_OS) AR="$(AR)" $(MAKE) $(LEVELDB_TARGET_FLAGS) OPT="$(CXXFLAGS) $(CPPFLAGS)" libleveldb.a

src/Makefile.include

@@ -5,6 +5,9 @@ LIBLEVELDB=$(top_builddir)/src/leveldb/libleveldb.a
 LIBMEMENV=$(top_builddir)/src/leveldb/libmemenv.a
 LIBBITCOINQT=$(top_builddir)/src/qt/libbitcoinqt.a
 
+INCLUDES += $(BDB_CPPFLAGS)
+LIBBITCOIN += $(BDB_LIBS)
+
 $(LIBBITCOIN):
 	$(MAKE) -C $(top_builddir)/src $(@F)
 

src/m4/bitcoin_find_bdb48.m4

@@ -0,0 +1,66 @@
+AC_DEFUN([BITCOIN_FIND_BDB48],[
+  AC_MSG_CHECKING([for Berkeley DB C++ headers])
+  BDB_CPPFLAGS=
+  BDB_LIBS=
+  bdbpath=X
+  bdb48path=X
+  bdbdirlist=
+  for _vn in 4.8 48 4 5 ''; do
+    for _pfx in b lib ''; do
+      bdbdirlist="$bdbdirlist ${_pfx}db${_vn}"
+    done
+  done
+  for searchpath in $bdbdirlist ''; do
+    test -n "${searchpath}" && searchpath="${searchpath}/"
+    AC_TRY_COMPILE([
+      #include <${searchpath}db_cxx.h>
+    ],[
+      #if !((DB_VERSION_MAJOR == 4 && DB_VERSION_MINOR >= 8) || DB_VERSION_MAJOR > 4)
+        #error "failed to find bdb 4.8+"
+      #endif
+    ],[
+      if test "x$bdbpath" = "xX"; then
+        bdbpath="${searchpath}"
+      fi
+    ],[
+      continue
+    ])
+    AC_TRY_COMPILE([
+      #include <${searchpath}db_cxx.h>
+    ],[
+      #if !(DB_VERSION_MAJOR == 4 && DB_VERSION_MINOR == 8)
+        #error "failed to find bdb 4.8"
+      #endif
+    ],[
+      bdb48path="${searchpath}"
+      break
+    ])
+  done
+  if test "x$bdbpath" = "xX"; then
+    AC_MSG_RESULT([no])
+    AC_MSG_ERROR(libdb_cxx headers missing)
+  elif test "x$bdb48path" = "xX"; then
+    BITCOIN_SUBDIR_TO_INCLUDE(BDB_CPPFLAGS,[${bdbpath}],db_cxx)
+    AC_ARG_WITH([incompatible-bdb],[AS_HELP_STRING([--with-incompatible-bdb], [allow using a bdb version other than 4.8])],[
+      AC_MSG_WARN([Found Berkeley DB other than 4.8; wallets opened by this build will not be portable!])
+    ],[
+      AC_MSG_ERROR([Found Berkeley DB other than 4.8, required for portable wallets (--with-incompatible-bdb to ignore)])
+    ])
+  else
+    BITCOIN_SUBDIR_TO_INCLUDE(BDB_CPPFLAGS,[${bdb48path}],db_cxx)
+    bdbpath="${bdb48path}"
+  fi
+  AC_SUBST(BDB_CPPFLAGS)
+  
+  # TODO: Ideally this could find the library version and make sure it matches the headers being used
+  for searchlib in db_cxx-4.8 db_cxx; do
+    AC_CHECK_LIB([$searchlib],[main],[
+      BDB_LIBS="-l${searchlib}"
+      break
+    ])
+  done
+  if test "x$BDB_LIBS" = "x"; then
+      AC_MSG_ERROR(libdb_cxx missing)
+  fi
+  AC_SUBST(BDB_LIBS)
+])

src/m4/bitcoin_subdir_to_include.m4

@@ -0,0 +1,12 @@
+dnl BITCOIN_SUBDIR_TO_INCLUDE([CPPFLAGS-VARIABLE-NAME],[SUBDIRECTORY-NAME],[HEADER-FILE])
+dnl SUBDIRECTORY-NAME must end with a path separator
+AC_DEFUN([BITCOIN_SUBDIR_TO_INCLUDE],[
+  if test "x$2" = "x"; then
+    AC_MSG_RESULT([default])
+  else
+    echo "#include <$2$3.h>" >conftest.cpp
+    newinclpath=`${CXXCPP} -M conftest.cpp 2>/dev/null | [ tr -d '\\n\\r\\\\' | sed -e 's/^.*[[:space:]:]\(\/[^[:space:]]*\)]$3[\.h[[:space:]].*$/\1/' -e t -e d`]
+    AC_MSG_RESULT([${newinclpath}])
+    eval "$1=\"\$$1\"' -I${newinclpath}'"
+  fi
+])