swap without events

src/base/base_win32/base_win32.c

@@ -126,7 +126,7 @@ String SwappedStateFromName(Arena *arena, String name)
 {
     TempArena scratch = BeginScratch(arena);
     String result = ZI;
-    String path = StringF(scratch.arena, "swap/%F.swp", FmtString(name));
+    String path = StringF(scratch.arena, "ppswap/%F.swp", FmtString(name));
     wchar_t *path_wstr = WstrFromString(scratch.arena, path);
     HANDLE handle = CreateFileW(path_wstr, GENERIC_READ, FILE_SHARE_READ, 0, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
     if (handle != INVALID_HANDLE_VALUE)
@@ -154,8 +154,10 @@ String SwappedStateFromName(Arena *arena, String name)
 void WriteSwappedState(String name, String data)
 {
     TempArena scratch = BeginScratchNoConflict();
+    /* TODO: Use directory non-relative to executable */
+    CreateDirectoryW(L"ppswap", 0);
     String result = ZI;
-    String path = StringF(scratch.arena, "swap/%F.swp", FmtString(name));
+    String path = StringF(scratch.arena, "ppswap/%F.swp", FmtString(name));
     wchar_t *path_wstr = WstrFromString(scratch.arena, path);
     HANDLE handle = CreateFileW(path_wstr, GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ, 0, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0);
     if (handle != INVALID_HANDLE_VALUE)
@@ -316,11 +318,6 @@ i32 W32_Main(void)
     }
 
     /* Set up exit events */
-#if HotSwappingIsEnabled
-    g->swap_event        = CreateEventW(0, 1, 0, L"Local\\pp_swap_start");
-#else
-    g->swap_event        = CreateEventW(0, 1, 0, 0);
-#endif
     g->panic_event       = CreateEventW(0, 1, 0, 0);
     g->startup_end_event = CreateEventW(0, 1, 0, 0);
     g->exit_begin_event  = CreateEventW(0, 1, 0, 0);
@@ -369,7 +366,6 @@ i32 W32_Main(void)
         HANDLE handles[] = {
             g->exit_begin_event,
             g->panic_event,
-            g->swap_event,
         };
         DWORD wake = WaitForMultipleObjects(countof(handles), handles, 0, INFINITE);
     }

src/base/base_win32/base_win32.h

@@ -38,7 +38,6 @@ Struct(W32_SharedState)
     Atomic32 panicking;
     wchar_t panic_wstr[4096];
     HANDLE panic_event;
-    HANDLE swap_event;
     HANDLE startup_end_event;
     HANDLE exit_begin_event;
     HANDLE exit_end_event;

src/meta/meta.c

@@ -100,36 +100,6 @@ LineCol LineColFromPos(String data, i64 pos)
     return result;
 }
 
-////////////////////////////////////////////////////////////
-//~ Swap
-
-#if PlatformIsWindows
-u64 SignalSwapStart(void)
-{
-    OS_Mkdir(Lit("swap"));
-    HANDLE swap_end_event = CreateEventW(0, 1, 0, L"Local\\pp_swap_end");
-    HANDLE swap_start_event = OpenEventW(EVENT_MODIFY_STATE, 0, L"Local\\pp_swap_start");
-    if (swap_start_event != 0)
-    {
-        SetEvent(swap_start_event);
-        CloseHandle(swap_start_event);
-    }
-    return (u64)swap_end_event;
-}
-
-void WaitForSwapEnd(u64 swap_start, i64 timeout_ns)
-{
-    HANDLE swap_start_event = (HANDLE)swap_start;
-    if (swap_start_event != 0)
-    {
-        DWORD timeout_ms = timeout_ns / 1000000;
-        WaitForSingleObject(swap_start_event, timeout_ms);
-    }
-}
-#else
-# error Swap signaling not implemented
-#endif
-
 ////////////////////////////////////////////////////////////
 //~ OS command job
 
@@ -905,8 +875,6 @@ JobDef(Build, _, __)
         }
     }
 
-    u64 swap_start = SignalSwapStart();
-
     //////////////////////////////
     //- Args
 
@@ -1085,9 +1053,14 @@ JobDef(Build, _, __)
 
         //- Link
 
-        WaitForSwapEnd(swap_start, NsFromSeconds(0.5f / 1000.f));
-
         String exe_file = Lit("pp.exe");
+        {
+            /* Wait for exe to become writable (once program closes) */
+            i64 timeout_ns = NsFromSeconds(0.5);
+            OS_File file = OS_OpenFile(exe_file, OS_FileFlag_Write, timeout_ns);
+            OS_CloseFile(file);
+        }
+
         i64 link_elapsed_ns = 0;
         if (ret == 0)
         {

src/meta/meta_file/meta_file.c

@@ -87,7 +87,7 @@ String F_ExtensionFromFile(String path)
 String F_DataFromFile(Arena *arena, String path)
 {
     String result = ZI;
-    OS_File file = OS_OpenFile(path, OS_FileFlag_Read);
+    OS_File file = OS_OpenFile(path, OS_FileFlag_Read, I64Max);
     result = OS_ReadEntireFile(arena, file);
     OS_CloseFile(file);
     return result;
@@ -98,7 +98,7 @@ String F_DataFromFile(Arena *arena, String path)
 
 void F_ClearWrite(String path, String data)
 {
-    OS_File file = OS_OpenFile(path, OS_FileFlag_Write | OS_FileFlag_Create);
+    OS_File file = OS_OpenFile(path, OS_FileFlag_Write | OS_FileFlag_Create, I64Max);
     OS_ClearWriteFile(file, data);
     OS_CloseFile(file);
 }

src/meta/meta_os/meta_os.h

@@ -7,7 +7,6 @@ Enum(OS_FileFlag)
     OS_FileFlag_Read   = (1 << 0),
     OS_FileFlag_Write  = (1 << 1),
     OS_FileFlag_Create = (1 << 2),
-    OS_FileFlag_NoWait = (1 << 3)
 };
 
 Struct(OS_File)
@@ -32,7 +31,7 @@ void OS_Startup(void);
 ////////////////////////////////////////////////////////////
 //~ @hookdecl File system operations
 
-OS_File OS_OpenFile(String path, OS_FileFlag flags);
+OS_File OS_OpenFile(String path, OS_FileFlag flags, i64 timeout_ns);
 void OS_CloseFile(OS_File file);
 String OS_ReadEntireFile(Arena *arena, OS_File file);
 void OS_ClearWriteFile(OS_File file, String data);

src/meta/meta_os/meta_os_win32/meta_os_win32.c

@@ -35,30 +35,29 @@ void OS_Startup(void)
 ////////////////////////////////////////////////////////////
 //~ @hookdef File system hooks
 
-OS_File OS_OpenFile(String path, OS_FileFlag flags)
+OS_File OS_OpenFile(String path, OS_FileFlag flags, i64 timeout_ns)
 {
     TempArena scratch = BeginScratchNoConflict();
     OS_File result = ZI;
     wchar_t *path_wstr = WstrFromString(scratch.arena, path);
-    b32 wait_for_access = 1;
     u32 share_mode = FILE_SHARE_READ;
     u32 create_mode = OPEN_EXISTING;
     u32 access_flags = 0;
     if (flags & OS_FileFlag_Read) access_flags |= GENERIC_READ;
     if (flags & OS_FileFlag_Write) access_flags |= GENERIC_WRITE;
     if (flags & OS_FileFlag_Create) create_mode = OPEN_ALWAYS;
-    if (flags & OS_FileFlag_NoWait) wait_for_access = 0;
+    i32 timeout_ms = timeout_ns / 1000000;
+    i32 elapsed_ms = 0;
     i32 delay_ms = 1;
-    HANDLE handle;
+    HANDLE handle = INVALID_HANDLE_VALUE;
-    while ((handle = CreateFileW(path_wstr, access_flags, share_mode, 0, create_mode, FILE_ATTRIBUTE_NORMAL, 0)) == INVALID_HANDLE_VALUE && wait_for_access)
+    for (;;)
     {
-        if (GetLastError() == ERROR_SHARING_VIOLATION)
+        handle = CreateFileW(path_wstr, access_flags, share_mode, 0, create_mode, FILE_ATTRIBUTE_NORMAL, 0);
+        if (handle == INVALID_HANDLE_VALUE && elapsed_ms < timeout_ms && GetLastError() == ERROR_SHARING_VIOLATION)
         {
             Sleep(delay_ms);
-            if (delay_ms < 1024)
+            elapsed_ms += delay_ms;
-            {
+            delay_ms = MinI32(delay_ms * 2, 1024);
-                delay_ms *= 2;
-            }
         }
         else
         {

src/pp/pp.c

@@ -92,7 +92,6 @@ ExitFuncDef(ShutdownUser)
         SwappedUserState *swap = PushStruct(scratch.arena, SwappedUserState);
         swap->s = *g;
         WriteSwappedState(Lit("pp_user"), StringFromStruct(swap));
-
         EndScratch(scratch);
     }