X-Git-Url: https://perl5.git.perl.org/perl5.git/blobdiff_plain/4fdae80067c447c675a6ac92c7959d2206e207ba..d58bf5aa3d3631a46847733b1ff1985b30140228:/scope.h

diff --git a/scope.h b/scope.h
index d0931b1..d9fe15a 100644
--- 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))
@@ -69,4 +70,64 @@
     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))
+