This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
Merge maint-5.004 branch (5.004_04) with mainline.
[perl5.git] / scope.h
diff --git a/scope.h b/scope.h
index d0931b1..d9fe15a 100644 (file)
--- a/scope.h
+++ b/scope.h
@@ -22,6 +22,7 @@
 #define SAVEt_REGCONTEXT 21
 #define SAVEt_STACK_POS  22
 #define SAVEt_I16      23
+#define SAVEt_OP       24
 
 #define SSCHECK(need) if (savestack_ix + need > savestack_max) savestack_grow()
 #define SSPUSHINT(i) (savestack[savestack_ix++].any_i32 = (I32)(i))
     SSPUSHINT(stack_sp - stack_base);  \
     SSPUSHINT(SAVEt_STACK_POS);                \
  } STMT_END
+#define SAVEOP()       save_op()
 
+/* A jmpenv packages the state required to perform a proper non-local jump.
+ * Note that there is a start_env initialized when perl starts, and top_env
+ * points to this initially, so top_env should always be non-null.
+ *
+ * Existence of a non-null top_env->je_prev implies it is valid to call
+ * longjmp() at that runlevel (we make sure start_env.je_prev is always
+ * null to ensure this).
+ *
+ * je_mustcatch, when set at any runlevel to TRUE, means eval ops must
+ * establish a local jmpenv to handle exception traps.  Care must be taken
+ * to restore the previous value of je_mustcatch before exiting the
+ * stack frame iff JMPENV_PUSH was not called in that stack frame.
+ * GSAR 97-03-27
+ */
+
+struct jmpenv {
+    struct jmpenv *    je_prev;
+    Sigjmp_buf         je_buf;         
+    int                        je_ret;         /* return value of last setjmp() */
+    bool               je_mustcatch;   /* longjmp()s must be caught locally */
+};
+
+typedef struct jmpenv JMPENV;
+
+#ifdef OP_IN_REGISTER
+#define OP_REG_TO_MEM  opsave = op
+#define OP_MEM_TO_REG  op = opsave
+#else
+#define OP_REG_TO_MEM  NOOP
+#define OP_MEM_TO_REG  NOOP
+#endif
+
+#define dJMPENV                JMPENV cur_env
+#define JMPENV_PUSH(v) \
+    STMT_START {                                       \
+       cur_env.je_prev = top_env;                      \
+       OP_REG_TO_MEM;                                  \
+       cur_env.je_ret = Sigsetjmp(cur_env.je_buf, 1);  \
+       OP_MEM_TO_REG;                                  \
+       top_env = &cur_env;                             \
+       cur_env.je_mustcatch = FALSE;                   \
+       (v) = cur_env.je_ret;                           \
+    } STMT_END
+#define JMPENV_POP \
+    STMT_START { top_env = cur_env.je_prev; } STMT_END
+#define JMPENV_JUMP(v) \
+    STMT_START {                                               \
+       OP_REG_TO_MEM;                                          \
+       if (top_env->je_prev)                                   \
+           Siglongjmp(top_env->je_buf, (v));                   \
+       if ((v) == 2)                                           \
+           exit(STATUS_NATIVE_EXPORT);                         \
+       PerlIO_printf(PerlIO_stderr(), "panic: top_env\n");     \
+       exit(1);                                                \
+    } STMT_END
+   
+#define CATCH_GET      (top_env->je_mustcatch)
+#define CATCH_SET(v)   (top_env->je_mustcatch = (v))
+