fixes for USE_WINDOWS_API && !NO_FILESYSTEM && !NO_WOLFSSL_DIR:

* in wc_port.h, add XWRITE and XREAD definitions and include <io.h>;
* in wolfSSL_BIO_read(), implement Windows support for XREAD and XWRITE;
* in wolfSSL_BIO_write_filename(), add 'b' flag to XFOPEN flags;
* in wolfSSL_RAND_file_name(), add support for XALTHOMEVARNAME, and add Windows definition for it to wc_port.h alongside XWRITE and XREAD.

fixes test_wolfSSL_BIO, test_wolfSSL_X509_print, test_wolfSSL_RAND, test_wolfSSL_RSA_print in cross-mingw-all-crypto scenario.

src/bio.c

@@ -312,7 +312,7 @@ int wolfSSL_BIO_read(WOLFSSL_BIO* bio, void* buf, int len)
                     ret = (int)XFREAD(buf, 1, (size_t)len, (XFILE)bio->ptr);
                 }
                 else {
-                #if !defined(USE_WINDOWS_API) && !defined(NO_WOLFSSL_DIR) && \
+                #if defined(XREAD) && !defined(NO_WOLFSSL_DIR) && \
                     !defined(WOLFSSL_NUCLEUS) && !defined(WOLFSSL_NUCLEUS_1_2)
                     ret = (int)XREAD(bio->num, buf, (size_t)len);
                 #else
@@ -682,7 +682,7 @@ int wolfSSL_BIO_write(WOLFSSL_BIO* bio, const void* data, int len)
                     ret = (int)XFWRITE(data, 1, (size_t)len, (XFILE)bio->ptr);
                 }
                 else {
-                #if !defined(USE_WINDOWS_API) && !defined(NO_WOLFSSL_DIR) && \
+                #if defined(XWRITE) && !defined(NO_WOLFSSL_DIR) && \
                     !defined(WOLFSSL_NUCLEUS) && !defined(WOLFSSL_NUCLEUS_1_2)
                     ret = (int)XWRITE(bio->num, data, (size_t)len);
                 #else
@@ -1617,7 +1617,12 @@ int wolfSSL_BIO_write_filename(WOLFSSL_BIO *bio, char *name)
             XFCLOSE((XFILE)bio->ptr);
         }
 
-        bio->ptr = XFOPEN(name, "w");
+        /* 'b' flag is ignored on POSIX targets, but on Windows it assures
+         * inhibition of LF<->CRLF rewriting, so that there is consistency
+         * between the size and contents of the representation in memory and on
+         * disk.
+         */
+        bio->ptr = XFOPEN(name, "wb");
         if (((XFILE)bio->ptr) == XBADFILE) {
             return WOLFSSL_FAILURE;
         }

src/ssl.c

@@ -23701,9 +23701,18 @@ const char* wolfSSL_RAND_file_name(char* fname, unsigned long len)
         const char ap[] = "/.rnd";
 
         WOLFSSL_MSG("Environment variable RANDFILE not set");
+
         if ((rt = XGETENV("HOME")) == NULL) {
+            #ifdef XALTHOMEVARNAME
+            if ((rt = XGETENV(XALTHOMEVARNAME)) == NULL) {
+                WOLFSSL_MSG("Environment variable HOME and " XALTHOMEVARNAME
+                            " not set");
+                return NULL;
+            }
+            #else
             WOLFSSL_MSG("Environment variable HOME not set");
             return NULL;
+            #endif
         }
 
         if (len > XSTRLEN(rt) + XSTRLEN(ap)) {
@@ -23713,7 +23722,7 @@ const char* wolfSSL_RAND_file_name(char* fname, unsigned long len)
             return fname;
         }
         else {
-            WOLFSSL_MSG("HOME too large for buffer");
+            WOLFSSL_MSG("Path too large for buffer");
             return NULL;
         }
     }

wolfssl/wolfcrypt/wc_port.h

@@ -716,12 +716,16 @@ WOLFSSL_ABI WOLFSSL_API int wolfCrypt_Cleanup(void);
     #if !defined(NO_WOLFSSL_DIR)\
         && !defined(WOLFSSL_NUCLEUS) && !defined(WOLFSSL_NUCLEUS_1_2)
         #if defined(USE_WINDOWS_API)
+            #include <io.h>
             #include <sys/stat.h>
             #ifndef XSTAT
                 #define XSTAT       _stat
             #endif
             #define XS_ISREG(s) (s & _S_IFREG)
             #define SEPARATOR_CHAR ';'
+            #define XWRITE      _write
+            #define XREAD       _read
+            #define XALTHOMEVARNAME "USERPROFILE"
 
         #elif defined(ARDUINO)
             #ifndef XSTAT