[haiku-commits] haiku: hrev43559 - src/system/libroot/posix/string
- From: fredrik.holmqvist@xxxxxxxxx
- To: haiku-commits@xxxxxxxxxxxxx
- Date: Sun, 25 Dec 2011 17:02:04 +0100 (CET)
hrev43559 adds 1 changeset to branch 'master'
old head: 753a02c15661a650762495257bf3abf1167998a7
new head: 11048d36190ef8eefdb3eec13dc1f1f91dddd11f
----------------------------------------------------------------------------
11048d3: Reworked strlen and strnlen to follow style guide.
Fix problems pointed out by Marcus.
[ Fredrik Holmqvist <fredrik.holmqvist@xxxxxxxxx> ]
----------------------------------------------------------------------------
Revision: hrev43559
Commit: 11048d36190ef8eefdb3eec13dc1f1f91dddd11f
URL: http://cgit.haiku-os.org/haiku/commit/?id=11048d3
Author: Fredrik Holmqvist <fredrik.holmqvist@xxxxxxxxx>
Date: Sun Dec 25 16:00:31 2011 UTC
----------------------------------------------------------------------------
2 files changed, 42 insertions(+), 44 deletions(-)
src/system/libroot/posix/string/strlen.c | 45 ++++++++++++-------------
src/system/libroot/posix/string/strnlen.c | 41 +++++++++++-----------
----------------------------------------------------------------------------
diff --git a/src/system/libroot/posix/string/strlen.c
b/src/system/libroot/posix/string/strlen.c
index 013c278..a94ded2 100644
--- a/src/system/libroot/posix/string/strlen.c
+++ b/src/system/libroot/posix/string/strlen.c
@@ -6,30 +6,29 @@
#include <string.h>
#include <SupportDefs.h>
-// From Bit twiddling hacks:
http://graphics.stanford.edu/~seander/bithacks.html
-#define hasZeroByte(value) (value - 0x01010101) & ~value & 0x80808080
+
+/* From Bit twiddling hacks:
+ http://graphics.stanford.edu/~seander/bithacks.html */
+#define HasZeroByte(value) ((value - 0x01010101) & ~value & 0x80808080)
+
size_t
-strlen(char const *s)
+strlen(const char* s)
{
- size_t i = 0;
- uint32 *value;
-
- //Make sure we use aligned access
- while (((uint32) s + i) & 3) {
- if (!s[i]) return i;
- i++;
- }
-
- //Check four bytes at once
- value = (uint32 *) (s + i);
- while (!(hasZeroByte(*value)))
- value++;
-
- //Find the exact length
- i = ((char *) value) - s;
- while (s[i])
- i++;
-
- return i;
+ size_t length = 0;
+ uint32* valuePointer;
+
+ /* Align access for four byte reads */
+ for (; (((addr_t) s + length) & 3) != 0; length++)
+ if (s[length] == '\0')
+ return length;
+
+ /* Check four bytes for zero char */
+ for (valuePointer = (uint32*) (s + length); !HasZeroByte(*valuePointer);
+ valuePointer++);
+
+ /* Find the exact length */
+ for (length = ((char*) valuePointer) - s; s[length] != '\0'; length++);
+
+ return length;
}
diff --git a/src/system/libroot/posix/string/strnlen.c
b/src/system/libroot/posix/string/strnlen.c
index 05a2920..677fd4f 100644
--- a/src/system/libroot/posix/string/strnlen.c
+++ b/src/system/libroot/posix/string/strnlen.c
@@ -7,32 +7,31 @@
#include <SupportDefs.h>
-// From Bit twiddling hacks:
http://graphics.stanford.edu/~seander/bithacks.html
-#define hasZeroByte(value) (value - 0x01010101) & ~value & 0x80808080
+/* From Bit twiddling hacks:
+ http://graphics.stanford.edu/~seander/bithacks.html */
+#define HasZeroByte(value) ((value - 0x01010101) & ~value & 0x80808080)
+
size_t
-strnlen(char const *s, size_t count)
+strnlen(const char* s, size_t count)
{
- size_t i = 0;
- uint32 *value;
-
- //Make sure we use aligned access
- while (((uint32) s + i) & 3) {
- if (i == count || !s[i]) return i;
- i++;
- }
+ size_t length = 0;
+ uint32* valuePointer;
+ uint32* maxScanPosition;
+ /* Align access for four byte reads */
+ for (; (((addr_t) s + length) & 3) != 0; length++)
+ if (length == count || s[length] == '\0')
+ return length;
- const uint32 * end = (uint32 *) s + count;
- //Check four bytes at once
- value = (uint32 *) (s + i);
- while (value < end && !(hasZeroByte(*value)) )
- value++;
+ /* Check four bytes for zero char */
+ maxScanPosition = (uint32*) (s + count - 4);
+ for (valuePointer = (uint32*) (s + length); valuePointer <=
maxScanPosition
+ && !HasZeroByte(*valuePointer); valuePointer++);
- //Find the exact length
- i = ((char *) value) - s;
- while (s[i] && i < count )
- i++;
+ /* Find the exact length */
+ for (length = ((char*) valuePointer) - s; length < count
+ && s[length] != '\0'; length++);
- return i;
+ return length;
}
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