use complex initializer in dosio.c

Sometimes the constant initializer doesn't suit for swappable context. Add support for complex initializers and use in dosio.c. Should fix crash with pcmos build. See dosemu2/dosemu2#2291
stsp · Oct 16, 2024 · ceb0c5d · ceb0c5d
1 parent f5abdf6
commit ceb0c5d
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Showing 2 changed files with 20 additions and 12 deletions.
diff --git a/include/libc/djctx.h b/include/libc/djctx.h
@@ -26,13 +26,14 @@ void djregister_ctx_hooks(void (*)(int), void (*)(void), void (*)(void),
 
 #define SW_CTX_MAX 100
 
-#define DJ64_DEFINE_SWAPPABLE_CONTEXT2(t, c, init, pre, post) \
+#define DJ64_DEFINE_SWAPPABLE_CONTEXT3(t, c, init, pre, post, cinit) \
 static struct t t##_contexts[SW_CTX_MAX]; \
 static void t##_init(int idx) \
 { \
   struct t *x = &t##_contexts[idx]; \
   assert(c != x); \
   *x = init; \
+  cinit(x); \
 } \
 static void t##_deinit(void) \
 { \
@@ -56,6 +57,10 @@ static void static_##t##_init(void) \
   djregister_ctx_hooks(t##_init, t##_deinit, t##_save, t##_restore); \
 }
 
+#define DJ64_DEFINE_SWAPPABLE_CONTEXT2(t, c, init, pre, post) \
+  static void _dummy_cinit(struct t *dummy) {} \
+  DJ64_DEFINE_SWAPPABLE_CONTEXT3(t, c, init, pre, post, _dummy_cinit)
+
 #define DJ64_DEFINE_SWAPPABLE_CONTEXT(t, c) \
   static const struct t ctx_##t##_init = {}; \
   DJ64_DEFINE_SWAPPABLE_CONTEXT2(t, c, ctx_##t##_init,,)

diff --git a/src/libc/dos/io/dosio.c b/src/libc/dos/io/dosio.c
@@ -11,13 +11,13 @@
 #include <libc/bss.h>
 #include <libc/djctx.h>
 
-static const char init_fh[] = {
-  O_TEXT,
-  O_TEXT,
-  O_TEXT,
-  O_BINARY,
-  O_BINARY
-};
+#define init_fh { \
+  O_TEXT, \
+  O_TEXT, \
+  O_TEXT, \
+  O_BINARY, \
+  O_BINARY, \
+}
 
 struct fh_state {
   char init_file_handle_modes[20];
@@ -32,6 +32,7 @@ char *__file_handle_modes;
 
 static const struct fh_state fhinit =
 {
+  .init_file_handle_modes = init_fh,
   .dosio_bss_count = -1,
   .count = 20,
 };
@@ -46,8 +47,12 @@ static void fhs_post(void)
 #define _RS(x) x = fhs->x
   _RS(__file_handle_modes);
 }
-DJ64_DEFINE_SWAPPABLE_CONTEXT2(fh_state, fhs, fhinit,
-    fhs_pre(), fhs_post());
+static void fhs_init(struct fh_state *st)
+{
+  st->__file_handle_modes = st->init_file_handle_modes;
+}
+DJ64_DEFINE_SWAPPABLE_CONTEXT3(fh_state, fhs, fhinit,
+    fhs_pre(), fhs_post(), fhs_init);
 
 #define init_file_handle_modes fhs->init_file_handle_modes
 #define dosio_bss_count fhs->dosio_bss_count
@@ -62,8 +67,6 @@ __file_handle_set(int fd, int mode)
   {
     dosio_bss_count = __bss_count;
     count = 20;
-    memcpy(init_file_handle_modes, init_fh, sizeof(init_fh));
-    __file_handle_modes = init_file_handle_modes;
   }
 
   /* Check for bogus values */