Move all _Generic() statements into lib/str2const.h, so that we can have

a less-typesafe callback for older compilers.

Provide a fallback if HAVE_GENERICS is not definedi (e.g. CentOS 7).

Author: sobomax

lib/str2const.h

@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2020 Sippy Software, Inc.
+ *
+ * This file is part of opensips, a free SIP server.
+ *
+ * opensips is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version
+ *
+ * opensips is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
+ *
+ */
+
+#ifndef __LIB_STR2CONST_H__
+#define __LIB_STR2CONST_H__
+
+#if defined(HAVE_GENERICS)
+#define str2const(_sp) ( \
+    _Generic((_sp), str *: _s2c, const str *: _cs2cc)(_sp) \
+)
+
+#define escape_user(sin, sout) ( \
+    _Generic(*(sin), str: _escape_userSS, str_const: _escape_user)(sin, sout) \
+)
+
+#define unescape_user(sin, sout) ( \
+    _Generic(*(sin), str: _unescape_userSS, str_const: _unescape_user)(sin, sout) \
+)
+
+#define escape_param(sin, sout) ( \
+    _Generic(*(sin), str: _escape_paramSS, str_const: _escape_param)(sin, sout) \
+)
+
+#define unescape_param(sin, sout) ( \
+    _Generic(*(sin), str: _unescape_paramSS, str_const: _unescape_param)(sin, sout) \
+)
+
+#define str_strcmp(_a, _b) _Generic(*(_a), \
+        str: _Generic(*(_b), \
+            str: _str_strcmpSS, \
+            str_const: _str_strcmpSC), \
+        str_const: _Generic(*(_b), \
+            str: _str_strcmpCS, \
+            str_const: _str_strcmpCC) \
+    )(_a, _b)
+#else /* !HAVE_GENERICS */
+#define str2const(_sp) ((str_const *)(void *)(_sp))
+#define escape_user(sin, sout) _escape_user(str2const(sin), sout)
+#define unescape_user(sin, sout) _unescape_user(str2const(sin), sout)
+#define escape_param(sin, sout) _escape_param(str2const(sin), sout)
+#define unescape_param(sin, sout) _unescape_param(str2const(sin), sout)
+#define str_strcmp(_a, _b) _str_strcmpCC(str2const(_a), str2const(_b))
+#endif /* HAVE_GENERICS */
+
+#endif /* __LIB_STR2CONST_H__ */

str.h

@@ -22,6 +22,7 @@
 #define str_h
 
 #include <string.h>
+#include "lib/str2const.h"
 
 /**
  * \file
@@ -74,10 +75,6 @@ typedef struct __str_const str_const;
 static inline const str_const *_cs2cc(const str *_sp) {return (const str_const *)(const void *)(_sp);}
 static inline str_const *_s2c(str *_sp) {return (str_const *)(void *)(_sp);}
 
-#define str2const(_sp) ( \
-    _Generic((_sp), str *: _s2c, const str *: _cs2cc)(_sp) \
-)
-
 static inline void init_str(str *dest, const char *src)
 {
 	dest->s = (char *)src;

strcommon.h

@@ -29,6 +29,7 @@
 #include "str.h"
 #include "md5.h"
 #include "crc.h"
+#include "lib/str2const.h"
 
 /*
  * add backslashes to special characters
@@ -45,26 +46,14 @@ void compute_md5(char *dst, const char *src, int src_len);
 
 int _escape_user(const str_const *sin, str *sout);
 static inline int _escape_userSS(const str *sin, str *sout){return _escape_user(str2const(sin), sout);}
-#define escape_user(sin, sout) ( \
-    _Generic(*(sin), str: _escape_userSS, str_const: _escape_user)(sin, sout) \
-)
 
 int _unescape_user(const str_const *sin, str *sout);
 static inline int _unescape_userSS(const str *sin, str *sout){return _unescape_user(str2const(sin), sout);}
-#define unescape_user(sin, sout) ( \
-    _Generic(*(sin), str: _unescape_userSS, str_const: _unescape_user)(sin, sout) \
-)
 
 int _escape_param(const str_const *sin, str *sout);
 static inline int _escape_paramSS(const str *sin, str *sout){return _escape_param(str2const(sin), sout);}
-#define escape_param(sin, sout) ( \
-    _Generic(*(sin), str: _escape_paramSS, str_const: _escape_param)(sin, sout) \
-)
 
 int _unescape_param(const str_const *sin, str *sout);
 static inline int _unescape_paramSS(const str *sin, str *sout){return _unescape_param(str2const(sin), sout);}
-#define unescape_param(sin, sout) ( \
-    _Generic(*(sin), str: _unescape_paramSS, str_const: _unescape_param)(sin, sout) \
-)
 
 #endif

ut.h

@@ -43,6 +43,8 @@
 #include "mem/mem.h"
 #include "mem/shm_mem.h"
 
+#include "lib/str2const.h"
+
 typedef struct _int_str_t {
 	union {
 		int i;
@@ -1033,14 +1035,6 @@ static inline int _str_strcmpCS(const str_const *a, const str *b)
 {
 	return _str_strcmpCC(a, str2const(b));
 }
-#define str_strcmp(_a, _b) _Generic(*(_a), \
-        str: _Generic(*(_b), \
-            str: _str_strcmpSS, \
-            str_const: _str_strcmpSC), \
-        str_const: _Generic(*(_b), \
-            str: _str_strcmpCS, \
-            str_const: _str_strcmpCC) \
-    )(_a, _b)
 
 /*
  * compares a str with a const null terminated string