rcx

commit 5dc9179db6c0d84a2598e91063d5aee33f630e3b
parent b3a948898f49969297d2ce5ea5e712e2fc807ca0
Author: Robert Russell <robertrussell.72001@gmail.com>
Date:   Fri, 24 Mar 2023 18:40:50 -0700

buffer: fix header alignment issues

Diffstat:
M
inc/buffer.h
 | 
6
++++--
M
src/buffer.c
 | 
18
+++++++++---------

2 files changed, 13 insertions(+), 11 deletions(-)
diff --git a/inc/buffer.h b/inc/buffer.h
@@ -1,5 +1,7 @@
 #pragma once
 
+#include <stdalign.h>
+
 #include "alloc.h"
 #include "debug.h"
 #include "def.h"
@@ -25,14 +27,14 @@ struct buf_hdr_ {
 	usize cap;
 	u32 refcnt;
 	u8 flags;
-	u8 data[];
+	// Followed padding and then data
 };
 
 #define buf_hdr_const_(n) struct { \
 		usize cap; \
 		u32 refcnt; \
 		u8 flags; \
-		u8 data[n]; \
+		alignas(BufHdr_) u8 data[n]; \
 	}
 
 #define buf_stack(s, ...) ((Buf)((BufHdr_ *)&(buf_hdr_const_( \
diff --git a/src/buffer.c b/src/buffer.c
@@ -9,7 +9,7 @@ buf_memory(void *mem, usize cap) {
 		"buf_memory: bad alignment");
 	BufHdr_ *h = mem;
 	*h = (BufHdr_){cap, 1, 0};
-	return h->data;
+	return (Buf)(h + 1);
 }
 
 Buf
@@ -17,7 +17,7 @@ buf_alloc(usize cap) {
 	BufHdr_ *h = r_alloc(sizeof *h + cap);
 	if (!h) return 0;
 	*h = (BufHdr_){cap, 1, BUF_FLAG_FREE_};
-	return h->data;
+	return (Buf)(h + 1);
 }
 
 Buf
@@ -25,21 +25,21 @@ buf_allocz(usize cap) {
 	BufHdr_ *h = r_allocz(sizeof *h + cap);
 	if (!h) return 0;
 	*h = (BufHdr_){cap, 1, BUF_FLAG_FREE_};
-	return h->data;
+	return (Buf)(h + 1);
 }
 
 Buf
 buf_ealloc(usize cap) {
 	BufHdr_ *h = r_ealloc(sizeof *h + cap);
 	*h = (BufHdr_){cap, 1, BUF_FLAG_FREE_};
-	return h->data;
+	return (Buf)(h + 1);
 }
 
 Buf
 buf_eallocz(usize cap) {
 	BufHdr_ *h = r_eallocz(sizeof *h + cap);
 	*h = (BufHdr_){cap, 1, BUF_FLAG_FREE_};
-	return h->data;
+	return (Buf)(h + 1);
 }
 
 int
@@ -47,7 +47,7 @@ buf_realloc(Buf *b, usize cap) {
 	BufHdr_ *h = *b ? (BufHdr_ *)*b - 1 : 0;
 	if (r_realloc(&h, sizeof *h + cap) < 0) return -1;
 	if (!*b) *h = (BufHdr_){cap, 1, BUF_FLAG_FREE_};
-	*b = h->data;
+	*b = (Buf)(h + 1);
 	return 0;
 }
 
@@ -56,7 +56,7 @@ buf_reallocz(Buf *b, usize cap) {
 	BufHdr_ *h = *b ? (BufHdr_ *)*b - 1 : 0;
 	if (r_reallocz(&h, sizeof *h + h->cap, sizeof *h + cap) < 0) return -1;
 	if (!*b) *h = (BufHdr_){cap, 1, BUF_FLAG_FREE_};
-	*b = h->data;
+	*b = (Buf)(h + 1);
 	return 0;
 }
 
@@ -65,7 +65,7 @@ buf_erealloc(Buf *b, usize cap) {
 	BufHdr_ *h = *b ? (BufHdr_ *)*b - 1 : 0;
 	r_erealloc(&h, sizeof *h + cap);
 	if (!*b) *h = (BufHdr_){cap, 1, BUF_FLAG_FREE_};
-	*b = h->data;
+	*b = (Buf)(h + 1);
 	return 0;
 }
 
@@ -74,7 +74,7 @@ buf_ereallocz(Buf *b, usize cap) {
 	BufHdr_ *h = *b ? (BufHdr_ *)*b - 1 : 0;
 	r_ereallocz(&h, sizeof *h + h->cap, sizeof *h + cap);
 	if (!*b) *h = (BufHdr_){cap, 1, BUF_FLAG_FREE_};
-	*b = h->data;
+	*b = (Buf)(h + 1);
 	return 0;
 }