From 31b6023a853c284ec8307f4cba3685f97def6964 Mon Sep 17 00:00:00 2001 From: Marcus Overhagen Date: Sat, 22 Oct 2005 21:43:54 +0000 Subject: [PATCH] Fixed an off-by-one error in the read_from_buffer function, testcase: size=7, in=7, first=0, read length=7 Fixed an off-by-(buffer->size) error in the write_to_buffer function, testcase: size=7, in=2, first=3, write length=3 git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@14473 a95241bf-73f2-0310-859d-f6bbb57e9c96 --- src/system/kernel/util/ring_buffer.cpp | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/system/kernel/util/ring_buffer.cpp b/src/system/kernel/util/ring_buffer.cpp index 1b223b7e48..9eb987bc26 100644 --- a/src/system/kernel/util/ring_buffer.cpp +++ b/src/system/kernel/util/ring_buffer.cpp @@ -50,7 +50,7 @@ read_from_buffer(struct ring_buffer *buffer, uint8 *data, ssize_t length, ssize_t bytesRead = length; - if (buffer->first + length < buffer->size) { + if (buffer->first + length <= buffer->size) { // simple copy if (user) { if (user_memcpy(data, buffer->buffer + buffer->first, length) < B_OK) @@ -91,7 +91,7 @@ write_to_buffer(struct ring_buffer *buffer, const uint8 *data, ssize_t length, return 0; ssize_t bytesWritten = length; - int32 position = buffer->first + buffer->in; + int32 position = (buffer->first + buffer->in) % buffer->size; if (position + length <= buffer->size) { // simple copy