Fix non-versioned libc's to also prepend '__' to internal symbols by using

strong aliases.

Signed-off-by: Martin Schlemmer <azarah@gentoo.org>

3 files changed, 19 insertions, 7 deletions

diff --git a/ChangeLog b/ChangeLog
index 2f7e83f..55df6d3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -14,6 +14,9 @@
 
   Rename configure.in to configure.ac.
 
+  Fix non-versioned libc's to also prepend '__' to internal symbols by using
+  strong aliases.
+
   28 Nov 2005; Martin Schlemmer <azarah@gentoo.org> configure.in, sandbox.c,
   sandbox_fdutils.c:
 
diff --git a/localdecls.h b/localdecls.h
index 22d5d2a..512030c 100644
--- a/localdecls.h
+++ b/localdecls.h
@@ -47,15 +47,20 @@
 #endif
 
 #if !HAVE_DLVSYM
-# define dlvsym(lib, sym, ver) dlsym(lib, sym)
+# define dlvsym(_lib, _sym, _ver) dlsym(_lib, _sym)
 #endif
 
-/* from glibc */
 #if HAVE_DLVSYM
-# define symbol_version(real, name, version) \
-	__asm__ (".symver " #real "," #name "@" #version)
-# define default_symbol_version(real, name, version) \
-	__asm__ (".symver " #real "," #name "@@" #version)
+/* Taken from glibc */
+# define symbol_version(_real, _name, _version) \
+	__asm__ (".symver " #_real "," #_name "@" #_version)
+# define default_symbol_version(_real, _name, _version) \
+	__asm__ (".symver " #_real "," #_name "@@" #_version)
 #endif
 
+/* Taken from glibc */
+# define strong_alias(_name, _aliasname) \
+	extern __typeof (_name) _aliasname __attribute__ ((alias (#_name)));
+
+
 #endif
diff --git a/scripts/gen_symbol_header.awk b/scripts/gen_symbol_header.awk
index 0426106..f6e877d 100644
--- a/scripts/gen_symbol_header.awk
+++ b/scripts/gen_symbol_header.awk
@@ -27,7 +27,8 @@ END {
 			# Defualt symbol have '@@' and not '@', so name it by
 			# prepending '__' rather than the symbol version so
 			# that we know what the name is in libsandbox.c ...
-			if (sym_full_names[x] ~ /@@/) {
+			# Also do this for non-versioned libc's ...
+			if (sym_full_names[x] ~ /@@/ || !symbol_array[2]) {
 				sym_real_name = "__" sym_index;
 			} else {
 				sym_real_name = sym_full_names[x];
@@ -54,6 +55,9 @@ END {
 				else
 					printf("symbol_version(%s, %s, %s);\n",
 					       sym_real_name, sym_index, symbol_array[2]);
+			} else {
+				printf("strong_alias(%s, %s);\n", sym_real_name,
+				       sym_index);
 			}
 			
 			printf("\n");