[PATCH v8 3/5] efi/boot.c: wrap PrintStr/PrintErr to allow const CHAR16* arguments

[Trammell Hudson <hudson@trmm.net>]

This patch wraps the EFI OutputString() method so that they can be
called with const arguments.  The OutputString method does not modify
its argument, although the prototype is missing const, so it is necssary
to cast away the const when calling it.

It also updates callers of PrintStr/PrintErr to remove unneeded un-const casts.

Signed-off-by: Trammell Hudson <hudson@trmm.net>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
---
 xen/common/efi/boot.c | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/xen/common/efi/boot.c b/xen/common/efi/boot.c
index 93cfeba7e1..bd629eb658 100644
--- a/xen/common/efi/boot.c
+++ b/xen/common/efi/boot.c
@@ -151,10 +151,17 @@ static struct file __initdata cfg;
 static struct file __initdata kernel;
 static struct file __initdata ramdisk;
 static struct file __initdata xsm;
-static CHAR16 __initdata newline[] = L"\r\n";
+static const CHAR16 __initconst newline[] = L"\r\n";
 
-#define PrintStr(s) StdOut->OutputString(StdOut, s)
-#define PrintErr(s) StdErr->OutputString(StdErr, s)
+static void __init PrintStr(const CHAR16 *s)
+{
+    StdOut->OutputString(StdOut, (CHAR16 *)s );
+}
+
+static void __init PrintErr(const CHAR16 *s)
+{
+    StdErr->OutputString(StdErr, (CHAR16 *)s );
+}
 
 /*
  * Include architecture specific implementation here, which references the
@@ -275,7 +282,7 @@ static bool __init match_guid(const EFI_GUID *guid1, const EFI_GUID *guid2)
 void __init noreturn blexit(const CHAR16 *str)
 {
     if ( str )
-        PrintStr((CHAR16 *)str);
+        PrintStr(str);
     PrintStr(newline);
 
     if ( !efi_bs )
@@ -316,7 +323,7 @@ static void __init PrintErrMesg(const CHAR16 *mesg, EFI_STATUS ErrCode)
     EFI_STATUS ErrIdx = ErrCode & ~EFI_ERROR_MASK;
 
     StdOut = StdErr;
-    PrintErr((CHAR16 *)mesg);
+    PrintErr(mesg);
     PrintErr(L": ");
 
     if( (ErrIdx < ARRAY_SIZE(ErrCodeToStr)) && ErrCodeToStr[ErrIdx] )
@@ -540,7 +547,7 @@ static char * __init split_string(char *s)
     return NULL;
 }
 
-static void __init handle_file_info(CHAR16 *name,
+static void __init handle_file_info(const CHAR16 *name,
                                     const struct file *file, const char *options)
 {
     if ( file == &cfg )
@@ -562,7 +569,7 @@ static bool __init read_file(EFI_FILE_HANDLE dir_handle, CHAR16 *name,
     EFI_FILE_HANDLE FileHandle = NULL;
     UINT64 size;
     EFI_STATUS ret;
-    CHAR16 *what = NULL;
+    const CHAR16 *what = NULL;
 
     if ( !name )
         PrintErrMesg(L"No filename", EFI_OUT_OF_RESOURCES);
-- 
2.25.1