tool/abi_symbols: omit known internal symbols

This patch prevents the abi_symbols tool from generating symbols that
are known to occur in shared objects but must not be part of a library
ABI. This saves a bit of time during library-porting work.

However, to avoid the accidental use of ABI symbol definitions that lack
any form of manual curation, the abi_symbols tool outputs a special
message, which is explicitly checked-for by the check_abi tool.

Fixes #3112

tool/check_abi

@@ -31,6 +31,16 @@ proc report_error { message } {
 }
 
 
+#
+# Warn about an ABI symbol definition that was generated by the 'abi_symbols'
+# tool but hasn't undergone any manual review. This is most likely an
+# accidental omission.
+#
+foreach line $abi_content {
+	if {$line == "# Please review the symbols and remove this line."} {
+		report_error "attempt to use unreviewed $abi_name ABI\n       at $abi_path" } }
+
+
 #
 # Extract symbol list w/o comments and empty lines, check for trailing spaces
 #
@@ -57,26 +67,12 @@ foreach line $abi_content {
 #
 # Check for absence of Genode-internal linking artifacts from ABI
 #
-
-#
-# The following symbols may appear in shared objects but should not by part
+# The listed symbols may appear in shared objects but should not by part
 # of any ABI.
 #
-set symbol_blacklist {
-	__bss_start
-	__eh_frame_start__
-	__exidx_end
-	__exidx_start
-	__l4sys_invoke_indirect
-	_ctors_end
-	_ctors_start
-	_edata
-	_end
-	_init
-	_parent_cap
-	_parent_cap_local_name
-	_parent_cap_thread_id
-}
+set fd [open "[file dirname $argv0]/internal_abi.list"]
+set symbol_blacklist [split [read $fd] "\n"]
+close $fd
 
 foreach line $abi_symbols {
 	set name [lindex $line 0]