libc/netdb: Add hostent_s to avoid the change of hostent

and let other function call the new internal function gethostentbyname_r

Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: Ic6137d6cf03f75d6ed33e23bf04ae74b7264e682

libs/libc/netdb/lib_netdb.h

@@ -43,6 +43,7 @@
 #include <nuttx/config.h>
 
 #include <netdb.h>
+#include <stdio.h>
 
 #ifdef CONFIG_LIBC_NETDB
 
@@ -78,6 +79,20 @@
  * Public Types
  ****************************************************************************/
 
+struct hostent_s
+{
+  FAR char  *h_name;       /* Official name of the host. */
+  FAR char **h_aliases;    /* A pointer to an array of pointers to the
+                            * alternative host names, terminated by a
+                            * null pointer. */
+  FAR int   *h_addrtypes;  /* A pointer to an array of address type. */
+  FAR int   *h_lengths;    /* A pointer to an array of the length, in bytes,
+                            * of the address. */
+  FAR char **h_addr_list;  /* A pointer to an array of pointers to network
+                            * addresses (in network byte order) for the host,
+                            * terminated by a null pointer. */
+};
+
 struct services_db_s
 {
   FAR const char *s_name;
@@ -105,6 +120,16 @@ EXTERN const struct services_db_s g_services_db[];
  * Public Function Prototypes
  ****************************************************************************/
 
+bool convert_hostent(const FAR struct hostent_s *in,
+                     int type, FAR struct hostent *out);
+
+ssize_t parse_hostfile(FAR FILE *stream, FAR struct hostent_s *host,
+                       FAR char *buf, size_t buflen);
+
+int gethostentbyname_r(FAR const char *name,
+                       FAR struct hostent_s *host, FAR char *buf,
+                       size_t buflen, FAR int *h_errnop);
+
 #undef EXTERN
 #ifdef __cplusplus
 }