Clean up errno.

kernel/libk.cpp

@@ -169,4 +169,13 @@ void libk_munmap(void* ptr, size_t size)
 	FreeKernelAddress(&addralloc);
 }
 
+#undef errno
+extern "C" { int errno; }
+
+extern "C"
+int* libk_get_errno_location(void)
+{
+	return &errno;
+}
+
 } // namespace Sortix

kernel/x64/interrupt.S

@@ -372,7 +372,7 @@ interrupt_handler_prepare:
 	pushq %rbp
 
 	# Push the current kernel errno value.
-	movl global_errno, %ebp
+	movl errno, %ebp
 	pushq %rbp
 
 	# Push whether a signal is pending.
@@ -396,7 +396,7 @@ load_interrupted_registers:
 
 	# Restore the previous kernel errno.
 	popq %rbp
-	movl %ebp, global_errno
+	movl %ebp, errno
 
 	# Remove CR2 from the stack.
 	addq $8, %rsp

kernel/x64/syscall.S

@@ -24,7 +24,7 @@
 .section .text
 .type syscall_handler, @function
 syscall_handler:
-	movl $0, global_errno # Reset errno
+	movl $0, errno
 
 	pushq %rbp
 	movq %rsp, %rbp
@@ -45,7 +45,7 @@ syscall_handler:
 
 	# Return to user-space, system call result in %rax:%rdx, errno in %ecx.
 	popq %rbp
-	movl global_errno, %ecx
+	movl errno, %ecx
 
 	# Zero registers to avoid information leaks.
 	# rax is return value.

kernel/x86/interrupt.S

@@ -369,7 +369,7 @@ fixup_relocate_stack_complete:
 	pushl %ebp
 
 	# Push the current kernel errno value.
-	movl global_errno, %ebp
+	movl errno, %ebp
 	pushl %ebp
 
 	# Push whether a signal is pending.
@@ -394,7 +394,7 @@ load_interrupted_registers:
 
 	# Restore the previous kernel errno.
 	popl %ebp
-	movl %ebp, global_errno
+	movl %ebp, errno
 
 	# Remove CR2 from the stack.
 	addl $4, %esp

kernel/x86/syscall.S

@@ -25,7 +25,7 @@
 .type syscall_handler, @function
 syscall_handler:
 	/* -- stack is 12 bytes from being 16-byte aligned -- */
-	movl $0, global_errno # Reset errno
+	movl $0, errno
 
 	pushl %ebp
 	/* -- stack is 8 bytes from being 16-byte aligned -- */
@@ -69,7 +69,7 @@ syscall_handler:
 
 	# Return to user-space, system call result in %eax:%edx, errno in %ecx.
 	popl %ebp
-	movl global_errno, %ecx
+	movl errno, %ecx
 
 	# Zero registers to avoid information leaks.
 	# eax is the return value.

libc/errno/errno.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011, 2012, 2014 Jonas 'Sortie' Termansen.
+ * Copyright (c) 2011, 2012, 2014, 2016 Jonas 'Sortie' Termansen.
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -18,27 +18,9 @@
  */
 
 #include <errno.h>
-#include <stddef.h>
 
 #ifndef __is_sortix_libk
 
 __thread int errno = 0;
 
-#else
-
-int global_errno = 0;
-errno_location_func_t errno_location_func = NULL;
-
-int* get_errno_location(void)
-{
-	if ( errno_location_func )
-		return errno_location_func();
-	return &global_errno;
-}
-
-void set_errno_location_func(errno_location_func_t func)
-{
-	errno_location_func = func;
-}
-
 #endif

libc/include/errno.h

@@ -22,10 +22,6 @@
 
 #include <sys/cdefs.h>
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 #define ENOTBLK 12
 #define ENODEV 13
 #define EWOULDBLOCK 14
@@ -117,6 +113,10 @@ extern "C" {
 
 #define EOPNOTSUPP ENOTSUP
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #if !defined(__is_sortix_libk) && !defined(__is_sortix_kernel)
 
 extern __thread int errno;
@@ -124,24 +124,15 @@ extern __thread int errno;
 
 #else
 
-/* Returns the address of the errno variable for this thread. */
-int* get_errno_location(void);
-
-/* get_errno_location will forward the request to a user-specified function if
-   specified, or if NULL, will return the global thread-shared errno value. */
-typedef int* (*errno_location_func_t)(void);
-void set_errno_location_func(errno_location_func_t func);
-
-#define errno (*get_errno_location())
+int* libk_get_errno_location(void);
+#define errno (*libk_get_errno_location())
 
 #endif
 
+#if __USE_SORTIX
 extern char* program_invocation_name;
 extern char* program_invocation_short_name;
-
-/* Satisfy broken programs that expect these to be macros. */
-#define program_invocation_name program_invocation_name
-#define program_invocation_short_name program_invocation_short_name
+#endif
 
 #ifdef __cplusplus
 } /* extern "C" */