refactor: Make Tox_Options own the passed proxy host and savedata.

This way, client code can immediately free their data and can pass
temporaries to the options setters.

.cirrus.yml

@@ -1,6 +1,6 @@
 ---
 bazel-opt_task:
-  timeout_in: 5m
+  timeout_in: 10m
   container:
     image: toxchat/toktok-stack:latest-release
     cpu: 2
@@ -18,7 +18,7 @@ bazel-opt_task:
         -//c-toxcore/auto_tests:tcp_relay_test # Cirrus doesn't allow external network connections.
 
 bazel-dbg_task:
-  timeout_in: 5m
+  timeout_in: 10m
   container:
     image: toxchat/toktok-stack:latest-debug
     cpu: 2

auto_tests/file_saving_test.c

@@ -13,8 +13,8 @@
 #include <stdlib.h>
 #include <string.h>
 
-#include "../testing/misc_tools.h"
 #include "../toxcore/ccompat.h"
+#include "../toxcore/tox.h"
 #include "auto_test_support.h"
 #include "check_compat.h"
 
@@ -70,7 +70,8 @@ static void load_data_decrypted(void)
 
     uint8_t *cipher = (uint8_t *)malloc(size);
     ck_assert(cipher != nullptr);
-    uint8_t *clear = (uint8_t *)malloc(size - TOX_PASS_ENCRYPTION_EXTRA_LENGTH);
+    const size_t clear_size = size - TOX_PASS_ENCRYPTION_EXTRA_LENGTH;
+    uint8_t *clear = (uint8_t *)malloc(clear_size);
     ck_assert(clear != nullptr);
     size_t read_value = fread(cipher, sizeof(*cipher), size, f);
     printf("Read read_value = %u of %u\n", (unsigned)read_value, (unsigned)size);
@@ -83,9 +84,10 @@ static void load_data_decrypted(void)
     struct Tox_Options *options = tox_options_new(nullptr);
     ck_assert(options != nullptr);
 
+    tox_options_set_experimental_owned_data(options, true);
     tox_options_set_savedata_type(options, TOX_SAVEDATA_TYPE_TOX_SAVE);
-
-    tox_options_set_savedata_data(options, clear, size);
+    tox_options_set_savedata_data(options, clear, clear_size);
+    free(clear);
 
     Tox_Err_New err;
 
@@ -103,7 +105,6 @@ static void load_data_decrypted(void)
                   "name returned by tox_self_get_name does not match expected result");
 
     tox_kill(t);
-    free(clear);
     free(cipher);
     free(readname);
     fclose(f);

toxcore/tox.h

@@ -574,7 +574,7 @@ struct Tox_Options {
      * TOX_PROXY_TYPE_NONE.
      *
      * The data pointed at by this member is owned by the user, so must
-     * outlive the options object.
+     * outlive the options object (unless experimental_owned_data is set).
      */
     const char *proxy_host;
 
@@ -629,10 +629,10 @@ struct Tox_Options {
     Tox_Savedata_Type savedata_type;
 
     /**
-     * The savedata.
+     * The savedata (either a Tox save or a secret key) to load from.
      *
-     * The data pointed at by this member is owned by the user, so must outlive
-     * the options object.
+     * The data pointed at by this member is owned by the user, so must
+     * outlive the options object (unless experimental_owned_data is set).
      */
     const uint8_t *savedata_data;
 
@@ -694,6 +694,34 @@ struct Tox_Options {
      * Default: false. May become true in the future (0.3.0).
      */
     bool experimental_disable_dns;
+
+    /**
+     * @brief Whether the savedata data is owned by the Tox_Options object.
+     *
+     * If true, the setters for savedata and proxy_host try to copy the string.
+     * If that fails, the value is not copied and the member is set to the
+     * user-provided pointer. In that case, the user must not free the string
+     * until the Tox_Options object is freed. Client code can check whether
+     * allocation succeeded by checking the returned bool. If
+     * experimental_owned_data is false, it will always return true. If set to
+     * true, the return value will be false on allocation failure.
+     *
+     * If set to true, this must be set before any other member that allocates
+     * memory is set.
+     */
+    bool experimental_owned_data;
+
+    /**
+     * @brief Owned pointer to the savedata data.
+     * @private
+     */
+    uint8_t *owned_savedata_data;
+
+    /**
+     * @brief Owned pointer to the proxy host.
+     * @private
+     */
+    char *owned_proxy_host;
 };
 #endif /* TOX_HIDE_DEPRECATED */
 
@@ -719,7 +747,7 @@ void tox_options_set_proxy_type(Tox_Options *options, Tox_Proxy_Type proxy_type)
 
 const char *tox_options_get_proxy_host(const Tox_Options *options);
 
-void tox_options_set_proxy_host(Tox_Options *options, const char *proxy_host);
+bool tox_options_set_proxy_host(Tox_Options *options, const char *proxy_host);
 
 uint16_t tox_options_get_proxy_port(const Tox_Options *options);
 
@@ -747,7 +775,7 @@ void tox_options_set_savedata_type(Tox_Options *options, Tox_Savedata_Type saved
 
 const uint8_t *tox_options_get_savedata_data(const Tox_Options *options);
 
-void tox_options_set_savedata_data(Tox_Options *options, const uint8_t savedata_data[], size_t length);
+bool tox_options_set_savedata_data(Tox_Options *options, const uint8_t savedata_data[], size_t length);
 
 size_t tox_options_get_savedata_length(const Tox_Options *options);
 
@@ -761,6 +789,10 @@ void *tox_options_get_log_user_data(const Tox_Options *options);
 
 void tox_options_set_log_user_data(Tox_Options *options, void *log_user_data);
 
+bool tox_options_get_experimental_owned_data(const Tox_Options *options);
+
+void tox_options_set_experimental_owned_data(Tox_Options *options, bool experimental_owned_data);
+
 bool tox_options_get_experimental_thread_safety(const Tox_Options *options);
 
 void tox_options_set_experimental_thread_safety(Tox_Options *options, bool experimental_thread_safety);

toxcore/tox_api.c

@@ -3,7 +3,8 @@
  */
 #include "tox.h"
 
-#include <stdlib.h>
+#include <stdlib.h> // free, malloc
+#include <string.h> // memcpy, strlen
 
 #include "ccompat.h"
 #include "tox_private.h"
@@ -164,9 +165,34 @@ const char *tox_options_get_proxy_host(const Tox_Options *options)
 {
     return options->proxy_host;
 }
-void tox_options_set_proxy_host(Tox_Options *options, const char *proxy_host)
+bool tox_options_set_proxy_host(Tox_Options *options, const char *proxy_host)
 {
-    options->proxy_host = proxy_host;
+    if (!options->experimental_owned_data) {
+        options->proxy_host = proxy_host;
+        return true;
+    }
+
+    if (options->owned_proxy_host != nullptr) {
+        free(options->owned_proxy_host);
+        options->owned_proxy_host = nullptr;
+    }
+    if (proxy_host == nullptr) {
+        options->proxy_host = nullptr;
+        return false;
+    }
+
+    const size_t proxy_host_length = strlen(proxy_host) + 1;
+    char *owned_ptr = (char *)malloc(proxy_host_length);
+    if (owned_ptr != nullptr) {
+        memcpy(owned_ptr, proxy_host, proxy_host_length);
+        options->proxy_host = owned_ptr;
+        options->owned_proxy_host = owned_ptr;
+    } else {
+        options->proxy_host = proxy_host;
+        options->owned_proxy_host = nullptr;
+    }
+
+    return true;
 }
 uint16_t tox_options_get_proxy_port(const Tox_Options *options)
 {
@@ -282,21 +308,61 @@ void tox_options_set_experimental_disable_dns(Tox_Options *options, bool experim
 {
     options->experimental_disable_dns = experimental_disable_dns;
 }
+bool tox_options_get_experimental_owned_data(const Tox_Options *options)
+{
+    return options->experimental_owned_data;
+}
+void tox_options_set_experimental_owned_data(
+    Tox_Options *options, bool experimental_owned_data)
+{
+    options->experimental_owned_data = experimental_owned_data;
+}
 
 const uint8_t *tox_options_get_savedata_data(const Tox_Options *options)
 {
     return options->savedata_data;
 }
 
-void tox_options_set_savedata_data(Tox_Options *options, const uint8_t *savedata_data, size_t length)
+bool tox_options_set_savedata_data(Tox_Options *options, const uint8_t *savedata_data, size_t length)
 {
-    options->savedata_data = savedata_data;
+    if (!options->experimental_owned_data) {
+        options->savedata_data = savedata_data;
+        options->savedata_length = length;
+        return true;
+    }
+
+    if (options->owned_savedata_data != nullptr) {
+        free(options->owned_savedata_data);
+        options->owned_savedata_data = nullptr;
+    }
+    if (savedata_data == nullptr) {
+        options->savedata_data = nullptr;
+        options->savedata_length = 0;
+        return false;
+    }
+
+    uint8_t *owned_ptr = (uint8_t *)malloc(length);
+    if (owned_ptr != nullptr) {
+        memcpy(owned_ptr, savedata_data, length);
+        options->savedata_data = owned_ptr;
+        options->owned_savedata_data = owned_ptr;
+    } else {
+        options->savedata_data = savedata_data;
+        options->owned_savedata_data = nullptr;
+    }
     options->savedata_length = length;
+
+    return true;
 }
 
 void tox_options_default(Tox_Options *options)
 {
     if (options != nullptr) {
+        // Free any owned data.
+        tox_options_set_proxy_host(options, nullptr);
+        tox_options_set_savedata_data(options, nullptr, 0);
+
+        // Set the rest to default values.
         const Tox_Options default_options = {false};
         *options = default_options;
         tox_options_set_ipv6_enabled(options, true);
@@ -308,6 +374,7 @@ void tox_options_default(Tox_Options *options)
         tox_options_set_experimental_thread_safety(options, false);
         tox_options_set_experimental_groups_persistence(options, false);
         tox_options_set_experimental_disable_dns(options, false);
+        tox_options_set_experimental_owned_data(options, false);
     }
 }
 
@@ -327,7 +394,12 @@ Tox_Options *tox_options_new(Tox_Err_Options_New *error)
 
 void tox_options_free(Tox_Options *options)
 {
-    free(options);
+    if (options != nullptr) {
+        // Free any owned data.
+        tox_options_set_proxy_host(options, nullptr);
+        tox_options_set_savedata_data(options, nullptr, 0);
+        free(options);
+    }
 }
 
 const char *tox_user_status_to_string(Tox_User_Status value)