implement global thread safe library initialization

2 files changed, 80 insertions, 13 deletions

diff --git a/common/userpref.c b/common/userpref.c
index 808c55c..5fb8458 100644
--- a/common/userpref.c
+++ b/common/userpref.c
@@ -609,8 +609,6 @@ userpref_error_t pair_record_generate_keys_and_certs(plist_t pair_record, key_da
         gnutls_x509_privkey_t host_privkey;
         gnutls_x509_crt_t host_cert;
 
-        gnutls_global_init();
-
         /* use less secure random to speed up key generation */
         gcry_control(GCRYCTL_ENABLE_QUICK_RANDOM);
 
@@ -770,8 +768,6 @@ userpref_error_t pair_record_generate_keys_and_certs(plist_t pair_record, key_da
         gnutls_free(exponent.data);
 
         gnutls_free(der_pub_key.data);
-
-        gnutls_global_deinit();
 #endif
         if (NULL != root_cert_pem.data && 0 != root_cert_pem.size &&
                 NULL != host_cert_pem.data && 0 != host_cert_pem.size)
diff --git a/src/idevice.c b/src/idevice.c
index 3d20069..28a62b0 100644
--- a/src/idevice.c
+++ b/src/idevice.c
@@ -36,10 +36,89 @@
 #endif
 #include "idevice.h"
 #include "common/userpref.h"
+#include "common/thread.h"
 #include "common/debug.h"
 
 #ifdef HAVE_OPENSSL
-static int openssl_init_done = 0;
+static mutex_t *mutex_buf = NULL;
+static void locking_function(int mode, int n, const char* file, int line)
+{
+        if (mode & CRYPTO_LOCK)
+                mutex_lock(&mutex_buf[n]);
+        else
+                mutex_unlock(&mutex_buf[n]);
+}
+
+static unsigned long id_function(void)
+{
+        return ((unsigned long)THREAD_ID);
+}
+#endif
+
+static void internal_idevice_init(void)
+{
+#ifdef HAVE_OPENSSL
+        int i;
+        SSL_library_init();
+
+        mutex_buf = malloc(CRYPTO_num_locks() * sizeof(mutex_t));
+        if (!mutex_buf)
+                return;
+        for (i = 0; i < CRYPTO_num_locks(); i++)
+                mutex_init(&mutex_buf[i]);
+
+        CRYPTO_set_id_callback(id_function);
+        CRYPTO_set_locking_callback(locking_function);
+#else
+        gnutls_global_init();
+#endif
+}
+
+static void internal_idevice_deinit(void)
+{
+#ifdef HAVE_OPENSSL
+        int i;
+        if (!mutex_buf)
+                return;
+        CRYPTO_set_id_callback(NULL);
+        CRYPTO_set_locking_callback(NULL);
+        for (i = 0; i < CRYPTO_num_locks(); i++)
+                mutex_destroy(&mutex_buf[i]);
+        free(mutex_buf);
+        mutex_buf = NULL;
+#else
+        gnutls_global_deinit();
+#endif
+}
+
+static thread_once_t init_once = THREAD_ONCE_INIT;
+static thread_once_t deinit_once = THREAD_ONCE_INIT;
+
+#ifdef WIN32
+int APIENTRY DllMain(HANDLE hModule, DWORD dwReason, LPVOID lpReserved)
+{
+        switch (dwReason) {
+        case DLL_PROCESS_ATTACH:
+                thread_once(&init_once, internal_idevice_init);
+                break;
+        case DLL_PROCESS_DETACH:
+                thread_once(&deinit_once, internal_idevice_deinit);
+                break;
+        default:
+                break;
+        }
+        return 1;
+}
+#else
+static void __attribute__((constructor)) libimobiledevice_initialize(void)
+{
+        thread_once(&init_once, internal_idevice_init);
+}
+
+static void __attribute__((destructor)) libimobiledevice_deinitialize(void)
+{
+        thread_once(&deinit_once, internal_idevice_deinit);
+}
 #endif
 
 static idevice_event_cb_t event_cb = NULL;
@@ -575,7 +654,6 @@ static void internal_ssl_cleanup(ssl_data_t ssl_data)
         if (ssl_data->ctx) {
                 SSL_CTX_free(ssl_data->ctx);
         }
-        openssl_init_done = 0;
 #else
         if (ssl_data->session) {
                 gnutls_deinit(ssl_data->session);
@@ -691,12 +769,6 @@ idevice_error_t idevice_connection_enable_ssl(idevice_connection_t connection)
         if (pair_record)
                 plist_free(pair_record);
 
-        /* Set up OpenSSL */
-        if (openssl_init_done == 0) {
-                SSL_library_init();
-                openssl_init_done = 1;
-        }
-
         BIO *ssl_bio = BIO_new(BIO_s_socket());
         if (!ssl_bio) {
                 debug_info("ERROR: Could not create SSL bio.");
@@ -761,7 +833,6 @@ idevice_error_t idevice_connection_enable_ssl(idevice_connection_t connection)
 
         /* Set up GnuTLS... */
         debug_info("enabling SSL mode");
-        gnutls_global_init();
         errno = 0;
         gnutls_certificate_allocate_credentials(&ssl_data_loc->certificate);
         gnutls_certificate_client_set_retrieve_function(ssl_data_loc->certificate, internal_cert_callback);