avformat/tls_openssl: fix warnings when openssl is lower version

JackLau1222 · quink-black · commit 177b92df2b05 · 2025-06-21T12:01:14.000+08:00
api doc: https://docs.openssl.org/1.0.2/man3/BIO_s_mem In higher versions (openssl 1.0.2 and higher), the function signature is BIO *BIO_new_mem_buf(const void *buf, int len), so passing a const string doesn't cause an warnings. However, in lower versions of OpenSSL, the function signature becomes BIO *BIO_new_mem_buf(void *buf, int len), which leads to warnings. OpenSSL guarantees that it will not modify the string, so it's safe to cast the pem_str to (void *) to avoid this warning. Signed-off-by: Jack Lau <jacklau1222@qq.com> Signed-off-by: Zhao Zhili <zhilizhao@tencent.com>
diff --git a/libavformat/tls_openssl.c b/libavformat/tls_openssl.c
@@ -415,7 +415,11 @@ int ff_ssl_gen_key_cert(char *key_buf, size_t key_sz, char *cert_buf, size_t cer
  */
 static EVP_PKEY *pkey_from_pem_string(const char *pem_str, int is_priv)
 {
+#if OPENSSL_VERSION_NUMBER < 0x10002000L /* OpenSSL 1.0.2 */
+    BIO *mem = BIO_new_mem_buf((void *)pem_str, -1);
+#else
     BIO *mem = BIO_new_mem_buf(pem_str, -1);
+#endif
     if (!mem) {
         av_log(NULL, AV_LOG_ERROR, "BIO_new_mem_buf failed\n");
         return NULL;
@@ -445,7 +449,11 @@ static EVP_PKEY *pkey_from_pem_string(const char *pem_str, int is_priv)
  */
 static X509 *cert_from_pem_string(const char *pem_str)
 {
+#if OPENSSL_VERSION_NUMBER < 0x10002000L /* OpenSSL 1.0.2 */
+    BIO *mem = BIO_new_mem_buf((void *)pem_str, -1);
+#else
     BIO *mem = BIO_new_mem_buf(pem_str, -1);
+#endif
     if (!mem) {
         av_log(NULL, AV_LOG_ERROR, "BIO_new_mem_buf failed\n");
         return NULL;
