nacl_io: Add inet_pton() and ip6addr_* consts.

native_client_sdk/src/libraries/nacl_io/syscalls/inet_pton.cc

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "nacl_io/ossocket.h"
+#if defined(PROVIDES_SOCKET_API) && !defined(__GLIBC__)
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <iostream>
+#include <sstream>
+#include <string>

[Sam Clegg, 2013/12/06 02:31:36]

Are you using any of these C++ headers?

If not can we just make this file a .c file like the others in this
folder?

Could probably also revert the header change if you did this.

[Sergey Ulanov, 2013/12/06 20:20:22]

No, removed.
Done.
It's still needed for C++ code that includes that header.

+
+#include "sdk_util/macros.h"
+
+// Helper function for inet_pton() for IPv4 addresses.
+static int inet_pton_v4(const char* src, void* dst) {
+  const int kIpv4AddressSize = 4;
+  const char* pos = src;
+  uint8_t result[kIpv4AddressSize] = {0};
+
+  for (int i = 0; i < kIpv4AddressSize; ++i) {
+    // strtol() won't treat whitespace characters in the beginning as an error,
+    // so check to ensure this is started with digit before passing to strtol().
+    if (isspace(*pos))
+      return 0;
+    char* end_pos;
+    unsigned long value = strtoul(pos, &end_pos, 10);
+    if (value > 255 || pos == end_pos)
+      return 0;
+    result[i] = static_cast<unsigned char>(value);
+    pos = end_pos;
+
+    if (i < (kIpv4AddressSize - 1)) {
+      if (*pos != '.')
+        return 0;
+      ++pos;
+    }
+  }
+  if (*pos != '\0')
+    return 0;
+  memcpy(dst, result, sizeof(result));
+  return 1;
+}
+
+// Helper function for inet_pton() for IPv6 addresses.
+int inet_pton_v6(const char* src, void* dst) {
+  // strtol() skips 0x in from of a number, while it's not allowed in IPv6
+  // addresses. Check that there is no 'x' in the string.
+  const char* pos = src;
+  while (*pos != '\0') {
+    if (*pos == 'x')
+      return 0;
+    pos++;
+  }
+  pos = src;
+
+  int kIpv6AddressSize = 16;
+  uint8_t result[kIpv6AddressSize];
+  memset(&result, 0, sizeof(result));
+  int double_colon_pos = -1;
+  int result_pos = 0;
+
+  if (*pos == ':') {
+    if (*(pos + 1) != ':')
+      return 0;
+    pos += 2;
+    double_colon_pos = 0;
+  }
+
+  while (*pos != '\0') {
+    // strtol() won't treat whitespace characters in the beginning as an error,
+    // so check to ensure this is started with digit before passing to strtol().
+    if (isspace(*pos))
+      return 0;
+    char* end_pos;
+    unsigned long word = strtoul(pos, &end_pos, 16);
+    if (word > 0xffff || pos == end_pos)
+      return 0;
+
+    if (*end_pos == '.')  {
+      if (result_pos + 4 > kIpv6AddressSize)
+        return 0;
+      // Parse rest of address as IPv4 address.
+      if (!inet_pton_v4(pos, result + result_pos))
+        return 0;
+      result_pos += 4;
+      break;
+    }
+
+    if (result_pos > kIpv6AddressSize - 2)
+      return 0;
+    result[result_pos] = (word & 0xFF00) >> 8;
+    result[result_pos + 1] = word & 0xFF;
+    result_pos += 2;
+
+    if (*end_pos == '\0')
+      break;
+
+    if (*end_pos != ':')
+      return 0;
+
+    pos = end_pos + 1;
+    if (*pos == ':') {
+      if (double_colon_pos != -1)
+        return 0;
+      double_colon_pos = result_pos;
+      ++pos;
+    }
+  }
+
+  // Finally move the data to the end in case the address contained '::'.
+  if (result_pos < kIpv6AddressSize) {
+    if (double_colon_pos == -1)
+      return 0;
+    int move_size = result_pos - double_colon_pos;
+    int gap_size = kIpv6AddressSize - result_pos;
+    memmove(result + kIpv6AddressSize - move_size,
+            result + double_colon_pos, move_size);
+    memset(result + double_colon_pos, 0, gap_size);
+  }
+
+  // Finally copy the result to the output buffer.
+  memcpy(dst, result, sizeof(result));
+
+  return 1;
+}
+
+EXTERN_C_BEGIN
+
+int inet_pton(int af, const char *src, void *dst) {
+  if (!src || !dst) {
+    return 0;
+  }
+  if (af == AF_INET) {
+    return inet_pton_v4(src, dst);
+  } else if (af == AF_INET6) {
+    return inet_pton_v6(src, dst);
+  }
+  errno = EAFNOSUPPORT;
+  return -1;
+}
+
+EXTERN_C_END
+
+#endif  // defined(PROVIDES_SOCKET_API) && !defined(__GLIBC__)
+