From d0ebe33a4a3b847df1a5ac270e098d287ec9fa21 Mon Sep 17 00:00:00 2001 From: Stefan Monnier Date: Sat, 8 Apr 2006 14:15:04 +0000 Subject: [PATCH] (OFFSETOF, PSEUDOVECSIZE): New macros. --- src/lisp.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/src/lisp.h b/src/lisp.h index 2eaa0987057..56b5645b9dc 100644 --- a/src/lisp.h +++ b/src/lisp.h @@ -702,6 +702,13 @@ struct Lisp_String unsigned char *data; }; +#ifdef offsetof +#define OFFSETOF(type,field) offsetof(type,field) +#else +#define OFFSETOF(type,field) \ + ((int)((char*)&((type*)0)->field - (char*)0)) +#endif + /* If a struct is made to look like a vector, this macro returns the length of the shortest vector that would hold that struct. */ #define VECSIZE(type) ((sizeof (type) - (sizeof (struct Lisp_Vector) \ @@ -709,6 +716,13 @@ struct Lisp_String + sizeof(Lisp_Object) - 1) /* round up */ \ / sizeof (Lisp_Object)) +/* Like VECSIZE, but used when the pseudo-vector has non-Lisp_Object fields + at the end and we need to compute the number of Lisp_Object fields (the + ones that the GC needs to trace). */ +#define PSEUDOVECSIZE(type, nonlispfield) \ + ((offsetof(type, nonlispfield) - offsetof(struct Lisp_Vector, contents[0])) \ + / sizeof (Lisp_Object)) + struct Lisp_Vector { EMACS_INT size; -- 2.39.2