bits: namespace REG_* macros to avoid colliding with sys/ucontext.h

The public bits.h on x86 and x86_64 unconditionally defined REG_R8
(and friends) as macros. Including <sys/ucontext.h> alongside
<libucontext/libucontext.h> then breaks because glibc declares the
same names as enum members, which the preprocessor rewrites into
invalid syntax. Rename the public macros to LIBUCONTEXT_REG_* so
libucontext stops shadowing libc symbols.

Author: daandemeyer

arch/x86/include/libucontext/bits.h

@@ -1,19 +1,19 @@
 #ifndef LIBUCONTEXT_BITS_H
 #define LIBUCONTEXT_BITS_H
 
-#define REG_GS		(0)
-#define REG_FS		(1)
-#define REG_ES		(2)
-#define REG_DS		(3)
-#define REG_EDI		(4)
-#define REG_ESI		(5)
-#define REG_EBP		(6)
-#define REG_ESP		(7)
-#define REG_EBX		(8)
-#define REG_EDX		(9)
-#define REG_ECX		(10)
-#define REG_EAX		(11)
-#define REG_EIP		(14)
+#define LIBUCONTEXT_REG_GS		(0)
+#define LIBUCONTEXT_REG_FS		(1)
+#define LIBUCONTEXT_REG_ES		(2)
+#define LIBUCONTEXT_REG_DS		(3)
+#define LIBUCONTEXT_REG_EDI		(4)
+#define LIBUCONTEXT_REG_ESI		(5)
+#define LIBUCONTEXT_REG_EBP		(6)
+#define LIBUCONTEXT_REG_ESP		(7)
+#define LIBUCONTEXT_REG_EBX		(8)
+#define LIBUCONTEXT_REG_EDX		(9)
+#define LIBUCONTEXT_REG_ECX		(10)
+#define LIBUCONTEXT_REG_EAX		(11)
+#define LIBUCONTEXT_REG_EIP		(14)
 
 typedef int libucontext_greg_t, libucontext_gregset_t[19];
 
@@ -47,4 +47,3 @@ typedef struct libucontext_ucontext {
 } libucontext_ucontext_t;
 
 #endif
-

arch/x86_64/include/libucontext/bits.h

@@ -3,29 +3,29 @@
 #ifndef LIBUCONTEXT_BITS_H
 #define LIBUCONTEXT_BITS_H
 
-#define REG_R8		(0)
-#define REG_R9 		(1)
-#define REG_R10 	(2)
-#define REG_R11		(3)
-#define REG_R12		(4)
-#define REG_R13		(5)
-#define REG_R14		(6)
-#define REG_R15		(7)
-#define REG_RDI		(8)
-#define REG_RSI		(9)
-#define REG_RBP		(10)
-#define REG_RBX		(11)
-#define REG_RDX		(12)
-#define REG_RAX		(13)
-#define REG_RCX		(14)
-#define REG_RSP		(15)
-#define REG_RIP		(16)
-#define REG_EFL		(17)
-#define REG_CSGSFS	(18)
-#define REG_ERR		(19)
-#define REG_TRAPNO	(20)
-#define REG_OLDMASK	(21)
-#define REG_CR2		(22)
+#define LIBUCONTEXT_REG_R8		(0)
+#define LIBUCONTEXT_REG_R9 		(1)
+#define LIBUCONTEXT_REG_R10 	(2)
+#define LIBUCONTEXT_REG_R11		(3)
+#define LIBUCONTEXT_REG_R12		(4)
+#define LIBUCONTEXT_REG_R13		(5)
+#define LIBUCONTEXT_REG_R14		(6)
+#define LIBUCONTEXT_REG_R15		(7)
+#define LIBUCONTEXT_REG_RDI		(8)
+#define LIBUCONTEXT_REG_RSI		(9)
+#define LIBUCONTEXT_REG_RBP		(10)
+#define LIBUCONTEXT_REG_RBX		(11)
+#define LIBUCONTEXT_REG_RDX		(12)
+#define LIBUCONTEXT_REG_RAX		(13)
+#define LIBUCONTEXT_REG_RCX		(14)
+#define LIBUCONTEXT_REG_RSP		(15)
+#define LIBUCONTEXT_REG_RIP		(16)
+#define LIBUCONTEXT_REG_EFL		(17)
+#define LIBUCONTEXT_REG_CSGSFS	(18)
+#define LIBUCONTEXT_REG_ERR		(19)
+#define LIBUCONTEXT_REG_TRAPNO	(20)
+#define LIBUCONTEXT_REG_OLDMASK	(21)
+#define LIBUCONTEXT_REG_CR2		(22)
 
 typedef long long libucontext_greg_t, libucontext_gregset_t[23];