Added constants that will be used by ares_getaddrinfo. Made ares_getnameinfo use the reentrant getservbyport (getservbyport_r) if it isavailable to ensure it works properly in a threaded environment

ares/CHANGES

@@ -1,5 +1,12 @@
   Changelog for the c-ares project
 
+* September 18
+
+- Added constants that will be used by ares_getaddrinfo
+
+- Made ares_getnameinfo use the reentrant getservbyport (getservbyport_r) if it is
+  available to ensure it works properly in a threaded environment.
+
 * September 10
 
 - configure fix for detecting a member in the sockaddr_in6 struct which failed

ares/acinclude.m4

@@ -269,3 +269,50 @@ AC_DEFUN([CARES_CHECK_CONSTANT], [
 ])
 
 
+dnl This macro determines how many parameters getservbyport_r takes
+AC_DEFUN([CARES_CHECK_GETSERVBYPORT_R], [
+  AC_MSG_CHECKING([how many arguments getservbyport_r takes])
+  AC_TRY_COMPILE(
+    [#include <netdb.h>],
+    [
+      int p1, p5;
+      char *p2, p4[4096];
+      struct servent *p3, *p6;
+      getservbyport_r(p1, p2, p3, p4, p5, &p6);
+    ], ac_func_getservbyport_r=6,
+    [AC_TRY_COMPILE(
+      [#include <netdb.h>],
+      [
+        int p1, p5;
+        char *p2, p4[4096];
+        struct servent *p3;
+        getservbyport_r(p1, p2, p3, p4, p5);
+      ], ac_func_getservbyport_r=5,
+      [AC_TRY_COMPILE(
+        [#include <netdb.h>],
+        [
+          int p1;
+          char *p2;
+          struct servent *p3;
+          struct servent_data p4;
+          getservbyport_r(p1, p2, p3, &p4);
+        ], ac_func_getservbyport_r=4, ac_func_getservbyport_r=0
+      )]
+    )]
+  )
+if test $ac_func_getservbyport_r != "0" ; then
+  AC_MSG_RESULT($ac_func_getservbyport_r)
+  AC_DEFINE(HAVE_GETSERVBYPORT_R, 1, [Specifies whether getservbyport_r is present])
+  AC_DEFINE_UNQUOTED(GETSERVBYPORT_R_ARGS, $ac_func_getservbyport_r, [Specifies the number of arguments to 
+getservbyport_r])
+  if test $ac_func_getservbyport_r = "4" ; then
+   AC_DEFINE(GETSERVBYPORT_R_BUFSIZE, sizeof(struct servent_data), [Specifies the size of the buffer to pass to 
+getservbyport_r])
+  else
+   AC_DEFINE(GETSERVBYPORT_R_BUFSIZE, 4096, [Specifies the size of the buffer to pass to getservbyport_r])
+  fi
+else
+  AC_MSG_RESULT([not found])
+fi
+])
+

ares/ares.h

@@ -69,6 +69,10 @@ extern "C" {
 /* ares_getnameinfo error codes */
 #define ARES_EBADFLAGS          18
 
+/* ares_getaddrinfo error codes */
+#define ARES_ENONAME		19
+#define ARES_EBADHINTS		20
+
 /* Flag values */
 #define ARES_FLAG_USEVC         (1 << 0)
 #define ARES_FLAG_PRIMARY       (1 << 1)
@@ -104,9 +108,27 @@ extern "C" {
 #define ARES_NI_LOOKUPHOST              (1 << 8)
 #define ARES_NI_LOOKUPSERVICE           (1 << 9)
 /* Reserved for future use */
-#define ARES_NI_IDN                     (1 << 10)
-#define ARES_NI_ALLOW_UNASSIGNED        (1 << 11)
-#define ARES_NI_USE_STD3_ASCII_RULES    (1 << 12)
+#define ARES_NI_IDN			(1 << 10)
+#define ARES_NI_IDN_ALLOW_UNASSIGNED	(1 << 11)
+#define ARES_NI_IDN_USE_STD3_ASCII_RULES (1 << 12)
+
+/* Addrinfo flag values */
+#define ARES_AI_CANONNAME		(1 << 0)
+#define ARES_AI_NUMERICHOST		(1 << 1)
+#define ARES_AI_PASSIVE			(1 << 2)
+#define ARES_AI_NUMERICSERV		(1 << 3)
+#define ARES_AI_V4MAPPED		(1 << 4)
+#define ARES_AI_ALL			(1 << 5)
+#define ARES_AI_ADDRCONFIG		(1 << 6)
+/* Reserved for future use */
+#define ARES_AI_IDN			(1 << 10)
+#define ARES_AI_IDN_ALLOW_UNASSIGNED	(1 << 11)
+#define ARES_AI_IDN_USE_STD3_ASCII_RULES (1 << 12)
+#define ARES_AI_CANONIDN		(1 << 13)
+
+#define ARES_AI_MASK			(ARES_AI_CANONNAME|ARES_AI_NUMERICHOST|ARES_AI_PASSIVE| \
+				 	 ARES_AI_NUMERICSERV|ARES_AI_V4MAPPED|ARES_AI_ALL| \
+					 ARES_AI_ADDRCONFIG)
 
 struct ares_options {
   int flags;

ares/ares_getnameinfo.c

@@ -256,7 +256,16 @@ static char *lookup_service(unsigned short port, int flags, char *buf)
         {
           struct servent *se;
           const char *proto;
- 
+#if GETSERVBYPORT_R_ARGS == 6
+          struct servent ret;
+          char buf[4096];
+          int len = 4096;
+#elif GETSERVBYPORT_R_ARGS == 5
+          char buf[4096];
+          int len = 4096;
+#elif GETSERVBYPORT_R_ARGS == 4
+          struct servent_data sed;
+#endif 
           if (flags & ARES_NI_UDP)
             proto = "udp";
           else if (flags & ARES_NI_SCTP)
@@ -265,7 +274,23 @@ static char *lookup_service(unsigned short port, int flags, char *buf)
             proto = "dccp";
           else
             proto = "tcp";
+#ifdef HAVE_GETSERVBYPORT_R
+  #if GETSERVBYPORT_R_ARGS == 6
+    if (getservbyport_r(port, proto, se, buf, len, &ret))
+      se = NULL;
+  #elif GETSERVBYPORT_R_ARGS == 5
+    se = getservbyport_r(port, proto, se, buf, len);
+  #elif GETSERVBYPORT_R_ARGS == 4
+    if (getservbyport_r(port, proto, se, &sed) == -1)
+      se = NULL;
+  #else
+    /* Lets just hope the OS uses TLS! */   
+    se = getservbyport(port, proto);
+  #endif
+#else
+          /* Lets just hope the OS uses TLS! */
           se = getservbyport(port, proto);
+#endif
           if (se && se->s_name)
             strcpy(buf, se->s_name);
           else

ares/configure.ac

@@ -347,6 +347,9 @@ AC_CHECK_SIZEOF(struct in_addr, ,
 
 AC_CHECK_FUNCS([bitncmp if_indextoname])
 
+dnl God bless non-standardized functions! We need to see which getservbyport_r variant is available
+CARES_CHECK_GETSERVBYPORT_R
+
 CURL_CHECK_NONBLOCKING_SOCKET
 
 AC_OUTPUT(Makefile)