further simplify linker/os_ext/os_core.c

src/linker/lnk_io.c

@@ -17,15 +17,75 @@ lnk_read_data_from_file_path(Arena *arena, String8 path)
   return data;
 }
 
+internal
+THREAD_POOL_TASK_FUNC(lnk_data_size_from_file_path_task)
+{
+  LNK_DiskReader *task = raw_task;
+
+  String8        path   = task->path_arr.v[task_id];
+  OS_Handle      handle = os_file_open(OS_AccessFlag_Read|OS_AccessFlag_ShareRead, path);
+  FileProperties props  = os_properties_from_file(handle);
+
+  task->handle_arr[task_id] = handle;
+  task->size_arr[task_id]   = props.size;
+}
+
+internal
+THREAD_POOL_TASK_FUNC(lnk_data_from_file_path_task)
+{
+  LNK_DiskReader *task = raw_task;
+
+  OS_Handle handle = task->handle_arr[task_id];
+  U64       size   = task->size_arr[task_id];
+  U8       *buffer = task->buffer + task->off_arr[task_id];
+
+  U64 read_size = os_file_read(handle, rng_1u64(0, size), buffer);
+  Assert(read_size == size);
+
+  task->data_arr.v[task_id] = str8(buffer, read_size);
+
+  os_file_close(handle);
+}
+
 internal String8Array
 lnk_read_data_from_file_path_parallel(TP_Context *tp, Arena *arena, String8Array path_arr)
 {
-  String8Array result = os_data_from_file_path_parallel(tp, arena, path_arr);
+  Temp scratch = scratch_begin(&arena,1);
+
+  LNK_DiskReader reader = {0};
+  reader.path_arr       = path_arr;
+  reader.handle_arr     = push_array_no_zero(scratch.arena, OS_Handle, path_arr.count);
+  reader.size_arr       = push_array_no_zero(scratch.arena, U64, path_arr.count);
+
+  // open handles and get sizes
+  tp_for_parallel(tp, 0, path_arr.count, lnk_data_size_from_file_path_task, &reader);
+
+  // compute file buffer size
+  U64 total_data_size = sum_array_u64(path_arr.count, reader.size_arr);
+
+  // assign offsets into file buffer
+  U64 *off_arr = push_array_no_zero(scratch.arena, U64, path_arr.count);
+  MemoryCopyTyped(off_arr, reader.size_arr, path_arr.count);
+  counts_to_offsets_array_u64(path_arr.count, off_arr);
+
+  reader.data_arr = str8_array_reserve(arena, path_arr.count);
+  reader.off_arr  = off_arr;
+  reader.buffer   = push_array_no_zero(arena, U8, total_data_size);
+
+  // read files and close handles
+  tp_for_parallel(tp, 0, path_arr.count, lnk_data_from_file_path_task, &reader);
+  
+  String8Array result = {0};
+  result.count        = path_arr.count;
+  result.v            = reader.data_arr.v;
+
   if (lnk_get_log_status(LNK_Log_IO_Read)) {
     for (U64 i = 0; i < result.count; ++i) {
       lnk_log_read(path_arr.v[i], result.v[i].size);
     }
   }
+
+  scratch_end(scratch);
   return result;
 }