refactor: tr_sys_dir_get_current() returns a std::string (#3581)

libtransmission/file-posix.cc

@@ -1207,42 +1207,26 @@ bool tr_sys_file_lock([[maybe_unused]] tr_sys_file_t handle, [[maybe_unused]] in
     return ret;
 }
 
-char* tr_sys_dir_get_current(tr_error** error)
+std::string tr_sys_dir_get_current(tr_error** error)
 {
-    char* ret = getcwd(nullptr, 0);
+    auto buf = std::vector<char>{};
+    buf.resize(PATH_MAX);
 
-    if (ret == nullptr && (errno == EINVAL || errno == ERANGE))
+    for (;;)
     {
-        size_t size = PATH_MAX;
-        char* tmp = nullptr;
-
-        do
+        if (char* ret = getcwd(std::data(buf), std::size(buf)); ret != nullptr)
         {
-            tmp = tr_renew(char, tmp, size);
-
-            if (tmp == nullptr)
-            {
-                break;
-            }
-
-            ret = getcwd(tmp, size);
-            size += 2048;
-        } while (ret == nullptr && errno == ERANGE);
-
-        if (ret == nullptr)
-        {
-            int const err = errno;
-            tr_free(tmp);
-            errno = err;
+            return ret;
         }
-    }
 
-    if (ret == nullptr)
-    {
-        set_system_error(error, errno);
-    }
+        if (errno != ERANGE)
+        {
+            set_system_error(error, errno);
+            return {};
+        }
 
-    return ret;
+        buf.resize(std::size(buf) * 2);
+    }
 }
 
 bool tr_sys_dir_create(char const* path, int flags, int permissions, tr_error** error)

libtransmission/file-win32.cc

@@ -1339,26 +1339,20 @@ bool tr_sys_file_lock(tr_sys_file_t handle, int operation, tr_error** error)
     return ret;
 }
 
-char* tr_sys_dir_get_current(tr_error** error)
+std::string tr_sys_dir_get_current(tr_error** error)
 {
-    char* ret = nullptr;
-
     if (auto const size = GetCurrentDirectoryW(0, nullptr); size != 0)
     {
         auto wide_ret = std::wstring{};
         wide_ret.resize(size);
         if (GetCurrentDirectoryW(std::size(wide_ret), std::data(wide_ret)) != 0)
         {
-            ret = tr_win32_native_to_utf8(std::data(wide_ret), std::size(wide_ret));
+            return tr_win32_native_to_utf8(wide_ret);
         }
     }
 
-    if (ret == nullptr)
-    {
-        set_system_error(error, GetLastError());
-    }
-
-    return ret;
+    set_system_error(error, GetLastError());
+    return {};
 }
 
 bool tr_sys_dir_create(char const* path, int flags, int permissions, tr_error** error)

libtransmission/file.h

@@ -644,7 +644,7 @@ bool tr_sys_file_write_line(tr_sys_file_t handle, std::string_view buffer, struc
  *         directory (use @ref tr_free to free it when no longer needed) on
  *         success, `nullptr` otherwise (with `error` set accordingly).
  */
-char* tr_sys_dir_get_current(struct tr_error** error = nullptr);
+std::string tr_sys_dir_get_current(struct tr_error** error = nullptr);
 
 /**
  * @brief Like `mkdir()`, but makes parent directories if needed.

tests/libtransmission/subprocess-test-program.cc

@@ -49,9 +49,8 @@ int main(int argc, char** argv)
     }
     else if (test_action == "--dump-cwd")
     {
-        char* const value = tr_sys_dir_get_current(nullptr);
-        tr_sys_file_write_line(fd, value != nullptr ? value : "<null>");
-        tr_free(value);
+        auto const value = tr_sys_dir_get_current(nullptr);
+        tr_sys_file_write_line(fd, !std::empty(value) ? value : "<null>");
     }
     else
     {

tests/libtransmission/subprocess-test.cc

@@ -56,8 +56,8 @@ protected:
 
     [[nodiscard]] static std::string nativeCwd()
     {
-        auto path = makeString(tr_sys_dir_get_current(nullptr));
-        tr_sys_path_native_separators(&path.front());
+        auto path = tr_sys_dir_get_current();
+        tr_sys_path_native_separators(path.data());
         return path;
     }
 

tests/libtransmission/test-fixtures.h

@@ -128,11 +128,9 @@ protected:
 
         tr_error* error = nullptr;
 
-        if (auto* path = tr_sys_dir_get_current(&error); path != nullptr)
+        if (auto path = tr_sys_dir_get_current(&error); !std::empty(path))
         {
-            auto ret = std::string{ path };
-            tr_free(path);
-            return ret;
+            return path;
         }
 
         std::cerr << "tr_sys_dir_get_current error: '" << error->message << "'" << std::endl;

utils/create.cc

@@ -129,12 +129,11 @@ int parseCommandLine(app_options& options, int argc, char const* const* argv)
 std::string tr_getcwd()
 {
     tr_error* error = nullptr;
-    if (char* const cur = tr_sys_dir_get_current(&error); cur != nullptr)
+    if (auto cur = tr_sys_dir_get_current(&error); !std::empty(cur))
     {
-        auto path = std::string{ cur };
-        tr_free(cur);
-        return path;
+        return cur;
     }
+
     fprintf(stderr, "getcwd error: \"%s\"", error->message);
     tr_error_free(error);
     return "";