Move libc_freeres_ptrs and libc_subfreeres to hidden/weak functions

They are both used by __libc_freeres to free all library malloc
allocated resources to help tooling like mtrace or valgrind with
memory leak tracking.

The current scheme uses assembly markers and linker script entries
to consolidate the free routine function pointers in the RELRO segment
and to be freed buffers in BSS.

This patch changes it to use specific free functions for
libc_freeres_ptrs buffers and call the function pointer array directly
with call_function_static_weak.

It allows the removal of both the internal macros and the linker
script sections.

Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>

4 files changed, 16 insertions, 4 deletions

diff --git a/inet/getnameinfo.c b/inet/getnameinfo.c
index 5c07b748bc..40c20b4be6 100644
--- a/inet/getnameinfo.c
+++ b/inet/getnameinfo.c
@@ -72,12 +72,13 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <libc-lock.h>
 #include <scratch_buffer.h>
 #include <net-internal.h>
+#include <set-freeres.h>
 
 #ifndef min
 # define min(x,y) (((x) > (y)) ? (y) : (x))
 #endif /* min */
 
-libc_freeres_ptr (static char *domain);
+static char *domain;
 
 /* Former NI_IDN_ALLOW_UNASSIGNED, NI_IDN_USE_STD3_ASCII_RULES flags,
    now ignored.  */
@@ -556,3 +557,5 @@ getnameinfo (const struct sockaddr *sa, socklen_t addrlen, char *host,
   return 0;
 }
 libc_hidden_def (getnameinfo)
+
+weak_alias (domain, __libc_getnameinfo_freemem_ptr)
diff --git a/inet/getnetgrent.c b/inet/getnetgrent.c
index 0b689e0ab0..a7c83740a0 100644
--- a/inet/getnetgrent.c
+++ b/inet/getnetgrent.c
@@ -19,9 +19,10 @@
 #include <netdb.h>
 #include <stdlib.h>
 #include <libc-lock.h>
+#include <set-freeres.h>
 
 /* Static buffer for return value.  We allocate it when needed.  */
-libc_freeres_ptr (static char *buffer);
+static char *buffer;
 /* All three strings should fit in a block of 1kB size.  */
 #define BUFSIZE 1024
 
@@ -47,3 +48,5 @@ getnetgrent (char **hostp, char **userp, char **domainp)
 
   return __getnetgrent_r (hostp, userp, domainp, buffer, BUFSIZE);
 }
+
+weak_alias (buffer, __libc_getnetgrent_freemem_ptr)
diff --git a/inet/rcmd.c b/inet/rcmd.c
index 2b95fa11d8..ad8a894907 100644
--- a/inet/rcmd.c
+++ b/inet/rcmd.c
@@ -80,6 +80,7 @@
 #include <sys/uio.h>
 #include <sigsetops.h>
 #include <shlib-compat.h>
+#include <set-freeres.h>
 
 
 int __ivaliduser (FILE *, uint32_t, const char *, const char *);
@@ -98,7 +99,7 @@ int iruserok (uint32_t raddr, int superuser, const char *ruser,
 
 libc_hidden_proto (iruserok_af)
 
-libc_freeres_ptr(static char *ahostbuf);
+static char *ahostbuf;
 
 int
 rcmd_af (char **ahost, u_short rport, const char *locuser, const char *remuser,
@@ -817,3 +818,5 @@ __validuser2_sa (FILE *hostf, struct sockaddr *ra, size_t ralen,
 
     return retval;
 }
+
+weak_alias (ahostbuf, __libc_rcmd_freemem_ptr)
diff --git a/inet/rexec.c b/inet/rexec.c
index c647b7ac34..1985fa4418 100644
--- a/inet/rexec.c
+++ b/inet/rexec.c
@@ -40,9 +40,10 @@
 #include <string.h>
 #include <unistd.h>
 #include <sys/uio.h>
+#include <set-freeres.h>
 
 int	rexecoptions;
-libc_freeres_ptr (static char *ahostbuf);
+static char *ahostbuf;
 
 int
 rexec_af (char **ahost, int rport, const char *name, const char *pass,
@@ -196,3 +197,5 @@ rexec (char **ahost, int rport, const char *name, const char *pass,
 {
 	return rexec_af(ahost, rport, name, pass, cmd, fd2p, AF_INET);
 }
+
+weak_alias (ahostbuf, __libc_rexec_freemem_ptr)