Use gai_strerrorA on Windows.

gai_strerror is one of the Windows functions which behaves differently
whether UNICODE is defined. See
https://docs.microsoft.com/en-us/windows/win32/intl/conventions-for-function-prototypes

Call gai_strerrorA so that we behave consistently in both modes. This
fixes the build failure in
https://chromium-review.googlesource.com/c/chromium/src/+/2613519.

It also fixes a type error in the connect BIO (built but not used in
Chromium), which wasn't noticed because ERR_add_error_data is a variadic
function and untyped. (The type error won't go out of bounds because
we're interpreting a NUL-terminated WCHAR* as a NUL-terminated char*.
The string will be misinterpreted, but it still will be terminated
either at the NUL WCHAR or, more likely, the upper zero byte of the
first Latin-1 character in the string.)

The ERR_add_error_data call raises the question of which of our char*
strings are UTF-8 and which are the POSIX locale / Windows code page
(when those are not also UTF-8). This CL doesn't address this and only
fixes the character width error. Realistically, calling code tosses
char* to printf so often that non-UTF-8 locales are probably a lost
cause. (Although right now we do not transform any OS error strings, so
tossing them to printf works fine. The outputs of functions like
ASN1_STRING_to_UTF8, not so much.)

Change-Id: Ie789730658829bde90022605ade2c86b8a65c3de
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/44964
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>

crypto/bio/socket_helper.c

@@ -55,7 +55,11 @@ int bio_ip_and_port_to_socket_and_addr(int *out_sock,
   ret = getaddrinfo(hostname, port_str, &hint, &result);
   if (ret != 0) {
     OPENSSL_PUT_ERROR(SYS, 0);
+#if defined(OPENSSL_WINDOWS)
+    ERR_add_error_data(1, gai_strerrorA(ret));
+#else
     ERR_add_error_data(1, gai_strerror(ret));
+#endif
     return 0;
   }
 

tool/transport_common.cc

@@ -156,7 +156,12 @@ bool Connect(int *out_sock, const std::string &hostname_and_port) {
 
   int ret = getaddrinfo(hostname.c_str(), port.c_str(), &hint, &result);
   if (ret != 0) {
-    fprintf(stderr, "getaddrinfo returned: %s\n", gai_strerror(ret));
+#if defined(OPENSSL_WINDOWS)
+    const char *error = gai_strerrorA(ret);
+#else
+    const char *error = gai_strerror(ret);
+#endif
+    fprintf(stderr, "getaddrinfo returned: %s\n", error);
     return false;
   }