diff options
| author | Olivier Martin <olivier.martin@arm.com> | 2014-04-11 10:59:48 +0000 |
|---|---|---|
| committer | oliviermartin <oliviermartin@6f19259b-4bc3-4df7-8a09-765794883524> | 2014-04-11 10:59:48 +0000 |
| commit | 135b09a2c26d9c28f02c4d356a62ca8817344e15 (patch) | |
| tree | d6195d13368d9acab0ccb31b5694a07096a72b8a /ArmPlatformPkg/Bds/BdsHelper.c | |
| parent | 6bcedcecb529a1bfa19df08e3a6ab300e7bf7764 (diff) | |
| download | edk2-135b09a2c26d9c28f02c4d356a62ca8817344e15.zip edk2-135b09a2c26d9c28f02c4d356a62ca8817344e15.tar.gz edk2-135b09a2c26d9c28f02c4d356a62ca8817344e15.tar.bz2 | |
ArmPlatformPkg/Bds: Introduced helper function to detect if an Ascii/Unicode string is printable
Some limitations:
- it only supports unicode string that use ASCII character (< 0x100)
- single character ASCII strings are interpreted as Unicode string
- string cannot be longer than 2 x BOOT_DEVICE_OPTION_MAX (600 bytes)
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Olivier Martin <olivier.martin@arm.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15455 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'ArmPlatformPkg/Bds/BdsHelper.c')
| -rw-r--r-- | ArmPlatformPkg/Bds/BdsHelper.c | 78 |
1 files changed, 77 insertions, 1 deletions
diff --git a/ArmPlatformPkg/Bds/BdsHelper.c b/ArmPlatformPkg/Bds/BdsHelper.c index b5a3fa9..152061d 100644 --- a/ArmPlatformPkg/Bds/BdsHelper.c +++ b/ArmPlatformPkg/Bds/BdsHelper.c @@ -1,6 +1,6 @@ /** @file
*
-* Copyright (c) 2011-2013, ARM Limited. All rights reserved.
+* Copyright (c) 2011 - 2014, ARM Limited. All rights reserved.
*
* This program and the accompanying materials
* are licensed and made available under the terms and conditions of the BSD License
@@ -338,3 +338,79 @@ IsUnicodeString ( return FALSE;
}
}
+
+/*
+ * Try to detect if the given string is an ASCII or Unicode string
+ *
+ * There are actually few limitation to this function but it is mainly to give
+ * a user friendly output.
+ *
+ * Some limitations:
+ * - it only supports unicode string that use ASCII character (< 0x100)
+ * - single character ASCII strings are interpreted as Unicode string
+ * - string cannot be longer than 2 x BOOT_DEVICE_OPTION_MAX (600 bytes)
+ *
+ * @param String Buffer that might contain a Unicode or Ascii string
+ * @param IsUnicode If not NULL this boolean value returns if the string is an
+ * ASCII or Unicode string.
+ */
+BOOLEAN
+IsPrintableString (
+ IN VOID* String,
+ OUT BOOLEAN *IsUnicode
+ )
+{
+ BOOLEAN UnicodeDetected;
+ BOOLEAN IsPrintable;
+ UINTN Index;
+ CHAR16 Character;
+
+ // We do not support NULL pointer
+ ASSERT (String != NULL);
+
+ // Test empty string
+ if (*(CHAR16*)String == L'\0') {
+ if (IsUnicode) {
+ *IsUnicode = TRUE;
+ }
+ return TRUE;
+ } else if (*(CHAR16*)String == '\0') {
+ if (IsUnicode) {
+ *IsUnicode = FALSE;
+ }
+ return TRUE;
+ }
+
+ // Limitation: if the string is an ASCII single character string. This comparison
+ // will assume it is a Unicode string.
+ if (*(CHAR16*)String < 0x100) {
+ UnicodeDetected = TRUE;
+ } else {
+ UnicodeDetected = FALSE;
+ }
+
+ IsPrintable = FALSE;
+ for (Index = 0; Index < BOOT_DEVICE_OPTION_MAX * 2; Index++) {
+ if (UnicodeDetected) {
+ Character = ((CHAR16*)String)[Index];
+ } else {
+ Character = ((CHAR8*)String)[Index];
+ }
+
+ if (Character == '\0') {
+ // End of the string
+ IsPrintable = TRUE;
+ break;
+ } else if ((Character < 0x20) || (Character > 0x7f)) {
+ // We only support the range of printable ASCII character
+ IsPrintable = FALSE;
+ break;
+ }
+ }
+
+ if (IsPrintable && IsUnicode) {
+ *IsUnicode = UnicodeDetected;
+ }
+
+ return IsPrintable;
+}
|