Add support for gethostbyaddr()

ChangeLog

@@ -10666,4 +10666,7 @@
 	* arch/sim/src/up_head.S: Implement board_power_off() for the simulation
 	  platform (2015-07-04).
 	* libc/unistd/lib_gethostname.c: Add support for sethostname() (2015-07-05).
+	* libc/net:  Add support for gethostbyname() and gethostbyaddr().  Also
+	  support included for the non-standard gethostbyname_r() and
+	  gethostbyaddr_r() (2015-07-08).
 

include/netdb.h

@@ -276,10 +276,11 @@ int                  getaddrinfo(FAR const char *restrict,
                                  FAR const char *restrict,
                                  FAR const struct addrinfo *restrict,
                                  FAR struct addrinfo **restrict);
-FAR struct hostent  *gethostbyaddr(FAR const void *, socklen_t, int);
 #endif
 
-FAR struct hostent  *gethostbyname(FAR const char *);
+FAR struct hostent  *gethostbyaddr(FAR const void *addr, socklen_t len,
+                                   int type);
+FAR struct hostent  *gethostbyname(FAR const char *name);
 
 #if 0 /* None of these are yet supported */
 FAR struct hostent  *gethostent(void);
@@ -304,6 +305,9 @@ void                 setservent(int);
 
 /* Non-standard interfaces similar to Glibc 2 interfaces */
 
+int gethostbyaddr_r(FAR const void *addr, socklen_t len, int type,
+                    FAR struct hostent *host, FAR char *buf,
+                    size_t buflen, int *h_errnop);
 int gethostbyname_r(FAR const char *name, FAR struct hostent *host,
                     FAR char *buf, size_t buflen, int *h_errnop);
 

libc/net/Make.defs

@@ -47,7 +47,8 @@ endif
 # netdb support
 
 ifeq ($(CONFIG_LIB_NETDB),y)
-CSRCS += lib_gethostbyname.c lib_gethostbynamer.c lib_parsehostfile.c
+CSRCS += lib_netdb.c lib_gethostbyname.c lib_gethostbynamer.c
+CSRCS += lib_gethostbyaddr.c lib_gethostbyaddrr.c lib_parsehostfile.c
 endif
 
 # Add the net directory to the build

libc/net/lib_gethostbyaddr.c

@@ -0,0 +1,90 @@
+/****************************************************************************
+ * libc/net/lib_gethostbyaddr.c
+ *
+ *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <netdb.h>
+#include <errno.h>
+
+#include "lib_internal.h"
+#include "net/lib_netdb.h"
+
+#ifdef CONFIG_LIB_NETDB
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: gethostbyaddr
+ *
+ * Description:
+ *   The gethostbyaddr() function returns a structure of type hostent for
+ *   the given host address addr of length len and address type type. Valid
+ *   address types are AF_INET and AF_INET6. The host address argument is a
+ *   pointer to a struct of a type depending on the address type, for example
+ *   a struct in_addr *  for address type AF_INET.
+ * 
+ * Input Parameters:
+ *   addr - The address of the host to find.
+ *   len - The length of the address
+ *   type - The type of the address
+ *
+ * Returned Value:
+ *   Upon successful completion, this function will return a pointer to a
+ *   hostent structure if the requested entry was found, and a null pointer
+ *   if the end of the database was reached or the requested entry was not
+ *   found.
+ *
+ *   Upon unsuccessful completion, gethostbyaddr() will set h_errno to
+ *   indicate the error
+ *
+ ****************************************************************************/
+
+FAR struct hostent *gethostbyaddr(FAR const void *addr, socklen_t len, int type)
+{
+  int ret;
+
+  DEBUGASSERT(addr != NULL);
+  ret = gethostbyaddr_r(addr, len, type, &g_hostent, g_hostbuffer,
+                        CONFIG_NETDB_BUFSIZE, &h_errno);
+  return ret == 0 ? &g_hostent : NULL;
+}
+
+#endif /* CONFIG_LIB_NETDB */

libc/net/lib_gethostbyaddrr.c

@@ -0,0 +1,188 @@
+/****************************************************************************
+ * libc/net/lib_gethostbyaddrr.c
+ *
+ *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <stdio.h>
+#include <string.h>
+#include <netdb.h>
+#include <errno.h>
+
+#include <arpa/inet.h>
+
+#include "lib_internal.h"
+#include "net/lib_netdb.h"
+
+#ifdef CONFIG_LIB_NETDB
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: gethostbyaddr_r
+ *
+ * Description:
+ *   The gethostbyaddr_r() function returns a structure of type hostent for
+ *   the given host address addr of length len and address type type. Valid
+ *   address types are AF_INET and AF_INET6. The host address argument is a
+ *   pointer to a struct of a type depending on the address type, for example
+ *   a struct in_addr *  for address type AF_INET.
+ * 
+ *   gethostbyaddr_r() is *not* POSIX but is similar to a Glibc extension and is
+ *   used internally by NuttX to implement the POSIX gethostbyaddr().
+ *
+ * Input Parameters:
+ *   addr - The address of the host to find.
+ *   len - The length of the address
+ *   type - The type of the address
+ *   host - Caller provided location to return the host data.
+ *   buf - Caller provided buffer to hold string data associated with the
+ *     host data.
+ *   buflen - The size of the caller-provided buffer
+ *   h_errnop - There h_errno value returned in the event of a failure.
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success, -1 (ERROR) is returned on a failure
+ *   with the returned h_errno value provided the reason for the failure.
+ *
+ ****************************************************************************/
+
+int gethostbyaddr_r(FAR const void *addr, socklen_t len, int type,
+                    FAR struct hostent *host, FAR char *buf,
+                    size_t buflen, int *h_errnop)
+{
+  FAR FILE *stream;
+  int herrnocode;
+  int nread;
+
+  DEBUGASSERT(addr != NULL && host != NULL && buf != NULL);
+  DEBUGASSERT(type == AF_INET || type == AF_INET6);
+
+  /* Make sure that the h_errno has a non-error code */
+
+  if (h_errnop)
+    {
+      *h_errnop = 0;
+    }
+
+  /* Search the hosts file for a match */
+
+  stream = fopen(CONFIG_NETDB_HOSTCONF_PATH, "r");
+  if (stream == NULL)
+    {
+      int errcode = errno;
+
+      ndbg("ERROR:  Failed to open the hosts file %s: %d\n",
+           CONFIG_NETDB_HOSTCONF_PATH, errcode);
+      UNUSED(errcode);
+
+      herrnocode = NO_RECOVERY;
+      goto errorout_with_herrnocode;
+    }
+
+  /* Loop reading entries from the hosts file until a match is found or
+   * until we hit the end-of-file.
+   */
+
+  do
+    {
+      /* Read the next entry from the hosts file */
+
+      nread = lib_parse_hostfile(stream, host, buf, buflen);
+      if (nread < 0)
+        {
+          /* Possible errors:
+           *     ERANGE - Buffer not big enough
+           *     ESPIPE - End of file (or possibly a read error).
+           *     EAGAIN - Error parsing the line (E.g., missing hostname)
+           */
+
+          if (nread == -ESPIPE)
+            {
+              nread = 0;
+            }
+          else if (nread != -EAGAIN)
+            {
+              herrnocode = NO_RECOVERY;
+              goto errorout_with_stream;
+            }
+        }
+      else if (nread > 0 && len == host->h_length && type == host->h_addrtype)
+        {
+          /* We successfully read the entry and the type and size of the
+           * address is good.  Now compare the addresses:
+           */
+
+          FAR char *hostaddr = host->h_addr;
+          if (hostaddr != NULL)
+            {
+              nvdbg("Comparing addresses...\n");
+              if (memcmp(addr, hostaddr, len) == 0)
+                {
+                   /* We have a match */
+
+                  fclose(stream);
+                  return OK;
+                }
+            }
+        }
+    }
+  while (nread != 0);
+
+  /* We get here when the end of the hosts file is encountered without
+   * finding the hostname.
+   */
+
+  herrnocode = HOST_NOT_FOUND;
+
+errorout_with_stream:
+  fclose(stream);
+
+errorout_with_herrnocode:
+  if (h_errnop)
+    {
+      *h_errnop = herrnocode;
+    }
+
+ return ERROR;
+}
+
+#endif /* CONFIG_LIB_NETDB */

libc/net/lib_gethostbyname.c

@@ -1,5 +1,5 @@
 /****************************************************************************
- * net/netdb/lib_gethostbyname.c
+ * libc/net/lib_gethostbyname.c
  *
  *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
@@ -43,24 +43,10 @@
 #include <errno.h>
 
 #include "lib_internal.h"
+#include "net/lib_netdb.h"
 
 #ifdef CONFIG_LIB_NETDB
 
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-#ifndef CONFIG_NETDB_BUFSIZE
-#  define CONFIG_NETDB_BUFSIZE 128
-#endif
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-static struct hostent g_hostent;
-static char g_hostbuffer[CONFIG_NETDB_BUFSIZE];
-
 /****************************************************************************
  * Public Functions
  ****************************************************************************/

libc/net/lib_gethostbynamer.c

@@ -1,5 +1,5 @@
 /****************************************************************************
- * net/netdb/lib_gethostbynamer.c
+ * libc/net/lib_gethostbynamer.c
  *
  *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
@@ -59,18 +59,6 @@
  * Private Type Definitions
  ****************************************************************************/
 
-/* This is the maximum number of alternate host names supported by this
- * implementation:
- */
-
-#ifndef CONFIG_NETDB_MAX_ALTNAMES
-#  define CONFIG_NETDB_MAX_ALTNAMES 4
-#endif
-
-#ifndef CONFIG_NETDB_HOSTCONF_PATH
-#  define CONFIG_NETDB_HOSTCONF_PATH "/etc/hosts"
-#endif
-
 /* This is the layout of the caller provided memory area */
 
 struct hostent_info_s
@@ -298,11 +286,11 @@ int gethostbyname_r(FAR const char *name, FAR struct hostent *host,
            *     EAGAIN - Error parsing the line (E.g., missing hostname)
            */
 
-          if (ESPIPE)
+          if (nread == -ESPIPE)
             {
               nread = 0;
             }
-          else if (ERANGE)
+          else if (nread != -EAGAIN)
             {
               herrnocode = NO_RECOVERY;
               goto errorout_with_stream;

libc/net/lib_netdb.c

@@ -0,0 +1,59 @@
+/****************************************************************************
+ * libc/net/lib_netdb.c
+ *
+ *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <netdb.h>
+
+#include "net/lib_netdb.h"
+
+#ifdef CONFIG_LIB_NETDB
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+struct hostent g_hostent;
+char g_hostbuffer[CONFIG_NETDB_BUFSIZE];
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+#endif /* CONFIG_LIB_NETDB */

libc/net/lib_netdb.h

@@ -0,0 +1,98 @@
+/****************************************************************************
+ * libc/net/lib_netdb.h
+ *
+ *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+#ifndef __LIBC_NET_LIB_NETDB_H
+#define __LIBC_NET_LIB_NETDB_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <netdb.h>
+
+#ifdef CONFIG_LIB_NETDB
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/* This is the maximum number of alternate host names supported by this
+ * implementation:
+ */
+
+#ifndef CONFIG_NETDB_MAX_ALTNAMES
+#  define CONFIG_NETDB_MAX_ALTNAMES 4
+#endif
+
+/* This is the path to the system hosts file */
+
+#ifndef CONFIG_NETDB_HOSTCONF_PATH
+#  define CONFIG_NETDB_HOSTCONF_PATH "/etc/hosts"
+#endif
+
+/* Size of the buffer available for host data */
+
+#ifndef CONFIG_NETDB_BUFSIZE
+#  define CONFIG_NETDB_BUFSIZE 128
+#endif
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+#ifdef __cplusplus
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+EXTERN struct hostent g_hostent;
+EXTERN char g_hostbuffer[CONFIG_NETDB_BUFSIZE];
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+#undef EXTERN
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __INCLUDE_NETDB_H */
+#endif /* __LIBC_NET_LIB_NETDB_H */

libc/net/lib_parsehostfile.c

@@ -1,5 +1,5 @@
 /****************************************************************************
- * net/netdb/lib_parsehostile.c
+ * libc/net/lib_parsehostile.c
  *
  *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
@@ -56,14 +56,6 @@
  * Pre-processor Definitions
  ****************************************************************************/
 
-/* This is the maximum number of alternate host names supported by this
- * implementation:
- */
-
-#ifndef CONFIG_NETDB_MAX_ALTNAMES
-#  define CONFIG_NETDB_MAX_ALTNAMES 4
-#endif
-
 /* Check if character is any kind of white space (except for newline) */
 
 #define lib_isspace(c) \