Merge pull request #22 from snonux/develop

Add context awareness to dgrep

1 files changed, 49 insertions, 0 deletions

diff --git a/internal/datas/rbuffer.go b/internal/datas/rbuffer.go
new file mode 100644
index 0000000..df8f622
--- /dev/null
+++ b/internal/datas/rbuffer.go
@@ -0,0 +1,49 @@
+package datas
+
+import "fmt"
+
+// RBuffer is a simple circular string ring buffer data structure.
+type RBuffer struct {
+	Capacity int
+	size     int
+	readPos  int
+	writePos int
+	data     []string
+}
+
+// NewRBuffer creates a new string ring buffer.
+func NewRBuffer(capacity int) (*RBuffer, error) {
+	if capacity < 1 {
+		return nil, fmt.Errorf("RBuffer capacity must not be less than 1")
+	}
+
+	r := RBuffer{
+		Capacity: capacity,
+		size:     capacity + 1,
+		data:     make([]string, capacity+1),
+	}
+
+	return &r, nil
+}
+
+// Add a value.
+func (r *RBuffer) Add(value string) {
+	r.data[r.writePos] = value
+	r.writePos = (r.writePos + 1) % r.size
+
+	if r.writePos == r.readPos {
+		r.readPos = (r.readPos + 1) % r.size
+	}
+}
+
+// Get a value.
+func (r *RBuffer) Get() (string, bool) {
+	if r.readPos == r.writePos {
+		// RBuffer is empty.
+		return "", false
+	}
+
+	value := r.data[r.readPos]
+	r.readPos = (r.readPos + 1) % r.size
+	return value, true
+}