Use locking in a way that makes more sense.
authorBodo Möller <bodo@openssl.org>
Mon, 7 Jun 1999 22:50:12 +0000 (22:50 +0000)
committerBodo Möller <bodo@openssl.org>
Mon, 7 Jun 1999 22:50:12 +0000 (22:50 +0000)
crypto/bio/b_sock.c

index d20042a..d29b29f 100644 (file)
@@ -100,6 +100,8 @@ static struct hostent *ghbn_dup(struct hostent *a);
 int BIO_get_host_ip(const char *str, unsigned char *ip)
        {
        int i;
+       int err = 1;
+       int locked = 0;
        struct hostent *he;
 
        i=get_ip(str,ip);
@@ -107,32 +109,42 @@ int BIO_get_host_ip(const char *str, unsigned char *ip)
        if (i < 0)
                {
                BIOerr(BIO_F_BIO_GET_HOST_IP,BIO_R_INVALID_IP_ADDRESS);
-               ERR_add_error_data(2,"host=",str);
-               return(0);
+               goto err;
                }
-       else
-               { /* do a gethostbyname */
-               if (!BIO_sock_init()) return(0);
 
-               he=BIO_gethostbyname(str);
-               if (he == NULL)
-                       {
-                       BIOerr(BIO_F_BIO_GET_HOST_IP,BIO_R_BAD_HOSTNAME_LOOKUP);
-                       ERR_add_error_data(2,"host=",str);
-                       return(0);
-                       }
+       /* do a gethostbyname */
+       if (!BIO_sock_init())
+               return(0); /* don't generate another error code here */
 
-               /* cast to short because of win16 winsock definition */
-               if ((short)he->h_addrtype != AF_INET)
-                       {
-                       BIOerr(BIO_F_BIO_GET_HOST_IP,BIO_R_GETHOSTBYNAME_ADDR_IS_NOT_AF_INET);
-                       ERR_add_error_data(2,"host=",str);
-                       return(0);
-                       }
-               for (i=0; i<4; i++)
-                       ip[i]=he->h_addr_list[0][i];
+       CRYPTO_w_lock(CRYPTO_LOCK_GETHOSTBYNAME);
+       locked = 1;
+       he=BIO_gethostbyname(str);
+       if (he == NULL)
+               {
+               BIOerr(BIO_F_BIO_GET_HOST_IP,BIO_R_BAD_HOSTNAME_LOOKUP);
+               goto err;
                }
-       return(1);
+
+       /* cast to short because of win16 winsock definition */
+       if ((short)he->h_addrtype != AF_INET)
+               {
+               BIOerr(BIO_F_BIO_GET_HOST_IP,BIO_R_GETHOSTBYNAME_ADDR_IS_NOT_AF_INET);
+               goto err;
+               }
+       for (i=0; i<4; i++)
+               ip[i]=he->h_addr_list[0][i];
+       err = 0;
+
+ err:
+       if (locked)
+               CRYPTO_w_unlock(CRYPTO_LOCK_GETHOSTBYNAME);
+       if (err)
+               {
+               ERR_add_error_data(2,"host=",str);
+               return 0;
+               }
+       else
+               return 1;
        }
 
 int BIO_get_port(const char *str, unsigned short *port_ptr)
@@ -327,7 +339,12 @@ struct hostent *BIO_gethostbyname(const char *name)
 
 /*     return(gethostbyname(name)); */
 
+#if 0 /* It doesn't make sense to use locking here: The function interface
+          * is not thread-safe, because threads can never be sure when
+          * some other thread destroys the data they were given a pointer to.
+          */
        CRYPTO_w_lock(CRYPTO_LOCK_GETHOSTBYNAME);
+#endif
        j=strlen(name);
        if (j < 128)
                {
@@ -357,7 +374,11 @@ struct hostent *BIO_gethostbyname(const char *name)
                        goto end;
                if (j > 128) /* too big to cache */
                        {
+#if 0 /* If we were trying to make this function thread-safe (which
+          * is bound to fail), we'd have to give up in this case
+          * (or allocate more memory). */
                        ret = NULL;
+#endif
                        goto end;
                        }
 
@@ -381,7 +402,9 @@ struct hostent *BIO_gethostbyname(const char *name)
                ghbn_cache[i].order=BIO_ghbn_miss+BIO_ghbn_hits;
                }
 end:
+#if 0
        CRYPTO_w_unlock(CRYPTO_LOCK_GETHOSTBYNAME);
+#endif
        return(ret);
        }