Obsolete p_secstodate.

This patch, relative to a tree with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html> (pending
review) applied, obsoletes p_secstodate, making the underlying
function __p_secstodate into a compat symbol not available for new
binaries or ports.  The calls in ns_print.c (part of incomplete
handling of TKEY) are changed to use %lu to print times instead of
trying to pretty-print the times any more.

Tested for x86_64.

	* resolv/res_debug.c (p_secstodate): Condition definition on
	[SHLIB_COMPAT (libresolv, GLIBC_2_0, GLIBC_2_27)].  Define
	directly as __p_secstodate, and as a compat symbol.  Do not use
	libresolv_hidden_def.
	* resolv/resolv.h (p_secstodate): Remove macro and function
	declaration.
	* resolv/ns_print.c (ns_sprintrrf): Print times with %lu, not
	using p_secstodate.
	* include/resolv.h (__p_secstodate): Do not use
	libresolv_hidden_proto.
	* resolv/Makefile (tests): Move tst-p_secstodate to ....
	(tests-internal): ... here.
	* resolv/tst-p_secstodate.c: Include <shlib-compat.h>.  Condition
	all contents on [TEST_COMPAT (libresolv, GLIBC_2_0, GLIBC_2_27)]
	and declare and use __p_secstodate and use compat_symbol_reference
	in that case.
	[!TEST_COMPAT (libresolv, GLIBC_2_0, GLIBC_2_27)] (do_test): Add
	implementation returning 77.

5 files changed, 33 insertions, 14 deletions

diff --git a/resolv/Makefile b/resolv/Makefile
index aff671042e..a98a84fa9e 100644
--- a/resolv/Makefile
+++ b/resolv/Makefile
@@ -55,7 +55,6 @@ tests += \
   tst-resolv-network \
   tst-resolv-res_init-multi \
   tst-resolv-search \
-  tst-p_secstodate \
 
 # These tests need libdl.
 ifeq (yes,$(build-shared))
@@ -77,6 +76,9 @@ endif
 # This test accesses __inet_ntop_length, an internal libc function.
 tests-internal += tst-inet_pton
 
+# This test accesses the __p_secstodate compat symbol.
+tests-internal += tst-p_secstodate
+
 # This test sends millions of packets and is rather slow.
 xtests += tst-resolv-qtypes
 
diff --git a/resolv/ns_print.c b/resolv/ns_print.c
index f55680c311..d61f5044b1 100644
--- a/resolv/ns_print.c
+++ b/resolv/ns_print.c
@@ -488,12 +488,12 @@ ns_sprintrrf(const u_char *msg, size_t msglen,
 
 		/* Inception. */
 		t = ns_get32(rdata);  rdata += NS_INT32SZ;
-		len = SPRINTF((tmp, "%s ", p_secstodate(t)));
+		len = SPRINTF((tmp, "%lu ", t));
 		T(addstr(tmp, len, &buf, &buflen));
 
 		/* Experation. */
 		t = ns_get32(rdata);  rdata += NS_INT32SZ;
-		len = SPRINTF((tmp, "%s ", p_secstodate(t)));
+		len = SPRINTF((tmp, "%lu ", t));
 		T(addstr(tmp, len, &buf, &buflen));
 
 		/* Mode , Error, Key Size. */
diff --git a/resolv/res_debug.c b/resolv/res_debug.c
index a4fbc569b6..7681ad4639 100644
--- a/resolv/res_debug.c
+++ b/resolv/res_debug.c
@@ -1052,6 +1052,7 @@ dn_count_labels(const char *name) {
 libresolv_hidden_def (__dn_count_labels)
 
 
+#if SHLIB_COMPAT (libresolv, GLIBC_2_0, GLIBC_2_27)
 /*
  * Make dates expressed in seconds-since-Jan-1-1970 easy to read.
  * SIG records are required to be printed like this, by the Secure DNS RFC.
@@ -1059,7 +1060,7 @@ libresolv_hidden_def (__dn_count_labels)
  * signed 32-bit range.
  */
 char *
-p_secstodate (u_long secs) {
+__p_secstodate (u_long secs) {
 	/* XXX nonreentrant */
 	static char output[15];		/* YYYYMMDDHHMMSS and null */
 	time_t clock = secs;
@@ -1084,13 +1085,14 @@ p_secstodate (u_long secs) {
 	   that, even given range checks on all fields with
 	   __builtin_unreachable called for out-of-range values.  */
 	DIAG_PUSH_NEEDS_COMMENT;
-#if __GNUC_PREREQ (7, 0)
+# if __GNUC_PREREQ (7, 0)
 	DIAG_IGNORE_NEEDS_COMMENT (8, "-Wformat-overflow=");
-#endif
+# endif
 	sprintf(output, "%04d%02d%02d%02d%02d%02d",
 		time->tm_year, time->tm_mon, time->tm_mday,
 		time->tm_hour, time->tm_min, time->tm_sec);
 	DIAG_POP_NEEDS_COMMENT;
 	return (output);
 }
-libresolv_hidden_def (__p_secstodate)
+compat_symbol (libresolv, __p_secstodate, __p_secstodate, GLIBC_2_0);
+#endif
diff --git a/resolv/resolv.h b/resolv/resolv.h
index e8c581ccd1..80a523e5e4 100644
--- a/resolv/resolv.h
+++ b/resolv/resolv.h
@@ -213,7 +213,6 @@ __END_DECLS
 #define p_fqname		__p_fqname
 #define p_fqnname		__p_fqnname
 #define p_option		__p_option
-#define p_secstodate		__p_secstodate
 #define p_time			__p_time
 #define p_type			__p_type
 #define p_rcode			__p_rcode
@@ -268,7 +267,6 @@ const unsigned char * p_fqnname (const unsigned char *__cp,
 const unsigned char * p_fqname (const unsigned char *,
 				const unsigned char *, FILE *) __THROW;
 const char *	p_option (unsigned long __option) __THROW;
-char *		p_secstodate (unsigned long) __THROW;
 int		dn_count_labels (const char *) __THROW;
 int		dn_comp (const char *, unsigned char *, int, unsigned char **,
 			 unsigned char **) __THROW;
diff --git a/resolv/tst-p_secstodate.c b/resolv/tst-p_secstodate.c
index 9dac1ad819..98e4d1f108 100644
--- a/resolv/tst-p_secstodate.c
+++ b/resolv/tst-p_secstodate.c
@@ -1,4 +1,4 @@
-/* Test p_secstodate.
+/* Test __p_secstodate compat symbol.
    Copyright (C) 2017 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -23,9 +23,16 @@
 #include <stdio.h>
 #include <string.h>
 
+#include <shlib-compat.h>
+
+#if TEST_COMPAT (libresolv, GLIBC_2_0, GLIBC_2_27)
+
+char *__p_secstodate (unsigned long int);
+compat_symbol_reference (libresolv, __p_secstodate, __p_secstodate, GLIBC_2_0);
+
 struct test
 {
-  /* Argument to p_secstodate.  */
+  /* Argument to __p_secstodate.  */
   unsigned long int in;
   /* Expected output.  */
   const char *out;
@@ -39,12 +46,12 @@ static const struct test tests[] =
     { 2147483647UL, "20380119031407" },
     { 2147483648UL, "<overflow>" },
     { 4294967295UL, "<overflow>" },
-#if ULONG_MAX > 0xffffffffUL
+# if ULONG_MAX > 0xffffffffUL
     { 4294967296UL, "<overflow>" },
     { 9999999999UL, "<overflow>" },
     { LONG_MAX, "<overflow>" },
     { ULONG_MAX, "<overflow>" },
-#endif
+# endif
   };
 
 static int
@@ -53,7 +60,7 @@ do_test (void)
   int ret = 0;
   for (size_t i = 0; i < array_length (tests); i++)
     {
-      char *p = p_secstodate (tests[i].in);
+      char *p = __p_secstodate (tests[i].in);
       printf ("Test %zu: %lu -> %s\n", i, tests[i].in, p);
       if (strcmp (p, tests[i].out) != 0)
 	{
@@ -64,4 +71,14 @@ do_test (void)
   return ret;
 }
 
+#else
+
+static int
+do_test (void)
+{
+  return 77;
+}
+
+#endif
+
 #include <support/test-driver.c>