From c62682cd07b397cad53a0905a93d884b639282c9 Mon Sep 17 00:00:00 2001
From: Aditya Patwardhan <aditya.patwardhan@espressif.com>
Date: Mon, 13 Sep 2021 01:00:13 +0530
Subject: [PATCH] Fix esp_mbedtls_write API Fix esp_wolfssl_write API Closes
 https://github.com/espressif/esp-idf/issues/7461

---
 components/esp-tls/esp_tls.h         | 4 ++++
 components/esp-tls/esp_tls_mbedtls.c | 4 ++--
 components/esp-tls/esp_tls_wolfssl.c | 2 +-
 3 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/components/esp-tls/esp_tls.h b/components/esp-tls/esp_tls.h
index a3ab33b3d4..f77b8c7ba0 100644
--- a/components/esp-tls/esp_tls.h
+++ b/components/esp-tls/esp_tls.h
@@ -470,6 +470,10 @@ int esp_tls_conn_http_new_async(const char *url, const esp_tls_cfg_t *cfg, esp_t
  *                   of bytes actually written to the TLS/SSL connection.
  *             - <0  if write operation was not successful, because either an
  *                   error occured or an action must be taken by the calling process.
+ *             - ESP_TLS_ERR_SSL_WANT_READ/
+ *               ESP_TLS_ERR_SSL_WANT_WRITE.
+ *                  if the handshake is incomplete and waiting for data to be available for reading.
+ *                  In this case this functions needs to be called again when the underlying transport is ready for operation.
  */
 static inline ssize_t esp_tls_conn_write(esp_tls_t *tls, const void *data, size_t datalen)
 {
diff --git a/components/esp-tls/esp_tls_mbedtls.c b/components/esp-tls/esp_tls_mbedtls.c
index 10db36338a..0f1fcb1149 100644
--- a/components/esp-tls/esp_tls_mbedtls.c
+++ b/components/esp-tls/esp_tls_mbedtls.c
@@ -190,9 +190,9 @@ ssize_t esp_mbedtls_write(esp_tls_t *tls, const char *data, size_t datalen)
                 ESP_LOGE(TAG, "write error :%d:", ret);
                 return ret;
             } else {
-                // Exitting the tls-write process as less than desired datalen are writable
+                // Exiting the tls-write process as less than desired datalen are writable
                 ESP_LOGD(TAG, "mbedtls_ssl_write() returned %d, already written %d, exitting...", ret, written);
-                return written;
+                return (written > 0) ? written : ret;
             }
         }
         written += ret;
diff --git a/components/esp-tls/esp_tls_wolfssl.c b/components/esp-tls/esp_tls_wolfssl.c
index 9faab69119..0894df5f00 100644
--- a/components/esp-tls/esp_tls_wolfssl.c
+++ b/components/esp-tls/esp_tls_wolfssl.c
@@ -370,7 +370,7 @@ ssize_t esp_wolfssl_read(esp_tls_t *tls, char *data, size_t datalen)
 ssize_t esp_wolfssl_write(esp_tls_t *tls, const char *data, size_t datalen)
 {
     ssize_t ret = wolfSSL_write( (WOLFSSL *)tls->priv_ssl, (unsigned char *) data, datalen);
-    if (ret < 0) {
+    if (ret <= 0) {
         ret = wolfSSL_get_error( (WOLFSSL *)tls->priv_ssl, ret);
         if (ret != ESP_TLS_ERR_SSL_WANT_READ  && ret != ESP_TLS_ERR_SSL_WANT_WRITE) {
             ESP_INT_EVENT_TRACKER_CAPTURE(tls->error_handle, ESP_TLS_ERR_TYPE_WOLFSSL, -ret);