Changes in uspace/lib/c/include/setjmp.h [2d1195c0:91e22dc] in mainline

File:

• uspace/lib/c/include/setjmp.h (modified) (3 diffs)

uspace/lib/c/include/setjmp.h

@@ -1 +1 @@
 /*
  * Copyright (c) 2008 Josef Cejka
+ * Copyright (c) 2013 Vojtech Horky
  * All rights reserved.
  *
@@ -30 +31 @@
  * @{
  */
-/** @file
+/** @file Long jump implementation.
+ *
+ * Implementation inspired by Jiri Zarevucky's code from
+ * http://bazaar.launchpad.net/~zarevucky-jiri/helenos/stdc/revision/1544/uspace/lib/posix/setjmp.h
  */
 
@@ -38 +42 @@
 #include <libarch/fibril.h>
 
-typedef context_t jmp_buf[1];
+struct jmp_buf_interal {
+        context_t context;
+        int return_value;
+};
+typedef struct jmp_buf_interal jmp_buf[1];
 
-extern int setjmp(jmp_buf env);
+/*
+ * Specified as extern to minimize number of included headers
+ * because this file is used as is in libposix too.
+ */
+extern int context_save(context_t *ctx) __attribute__((returns_twice));
+
+/**
+ * Save current environment (registers).
+ *
+ * This function may return twice.
+ *
+ * @param env Variable where to save the environment (of type jmp_buf).
+ * @return Whether the call returned after longjmp.
+ * @retval 0 Environment was saved, normal execution.
+ * @retval other longjmp was executed and returned here.
+ */
+#define setjmp(env) \
+        ((env)[0].return_value = 0, \
+        context_save(&(env)[0].context), \
+        (env)[0].return_value)
+
 extern void longjmp(jmp_buf env, int val) __attribute__((noreturn));