From f8041c2bfa3ecda6b1e3ea770c21ff7892308565 Mon Sep 17 00:00:00 2001
From: Kyle Isom <kyle@imap.cc>
Date: Mon, 9 Oct 2023 12:45:19 -0700
Subject: [PATCH] Finish basic buffer implementation.

---
 Buffer.cc     | 72 +++++++++++++++++++++++++++++++++++++++++++++------
 Buffer.h      | 21 ++++++++++-----
 bufferTest.cc | 13 ++++++++++
 3 files changed, 92 insertions(+), 14 deletions(-)

diff --git a/Buffer.cc b/Buffer.cc
index 37d43cd..795c2f7 100644
--- a/Buffer.cc
+++ b/Buffer.cc
@@ -29,7 +29,7 @@ nearestPower(size_t x)
 	x |= x >> 16;
 	x |= x >> 32;
 
-	return x;
+	return x+1;
 }
 
 
@@ -56,6 +56,14 @@ Buffer::Buffer(const char *data)
 }
 
 
+bool
+Buffer::Append(const char *s)
+{
+	size_t	slen = strnlen(s, maxReasonableLine);
+
+	return this->Append((uint8_t *)s, slen);
+}
+
 bool
 Buffer::Append(uint8_t *data, size_t datalen)
 {
@@ -78,12 +86,23 @@ Buffer::Append(uint8_t c)
 	return this->Append(&c, 1);
 }
 
+
+bool
+Buffer::Insert(size_t index, const char *s)
+{
+	size_t	slen = strnlen(s, maxReasonableLine);
+
+	return this->Insert(index, (uint8_t *)(s), slen);
+}
+
+
 bool
 Buffer::Insert(size_t index, uint8_t *data, size_t datalen)
 {
-	auto	resized = this->shift(index, datalen);
+	auto	resized = this->shiftRight(index, datalen);
 
 	memcpy(this->contents + index, data, datalen);
+	this->length += datalen;
 	return resized;
 }
 
@@ -94,6 +113,23 @@ Buffer::Insert(size_t index, uint8_t c)
 }
 
 
+bool
+Buffer::Remove(size_t index, size_t count)
+{
+	auto resized = this->shiftLeft(index, count);
+
+	this->length -= count;
+	return resized;
+}
+
+
+bool
+Buffer::Remove(size_t index)
+{
+	return this->Remove(index, 1);
+}
+
+
 void
 Buffer::Resize(size_t newCapacity)
 {
@@ -103,6 +139,7 @@ Buffer::Resize(size_t newCapacity)
 
 	uint8_t *newContents = new uint8_t[newCapacity];
 
+	memset(newContents, 0, newCapacity);
 	if (this->length > 0) {
 		memcpy(newContents, this->contents, this->length);
 	}
@@ -140,8 +177,9 @@ Buffer::Clear()
 void
 Buffer::Reclaim()
 {
+	this->Clear();
+
 	delete this->contents;
-	this->length = 0;
 	this->capacity = 0;
 }
 
@@ -158,7 +196,7 @@ Buffer::mustGrow(size_t delta)
 
 
 bool
-Buffer::shift(size_t offset, size_t delta)
+Buffer::shiftRight(size_t offset, size_t delta)
 {
 	auto	resized = false;
 	auto	newCap = this->mustGrow(delta);
@@ -168,13 +206,31 @@ Buffer::shift(size_t offset, size_t delta)
 		resized = true;
 	}
 
-	
-	for (size_t i = this->length; i >= offset; i++) {
-		this->contents[i+delta] = this->contents[i];
-	}
+	if (this->length == 0)	return 0;
 
+	memmove(this->contents+(offset+delta), this->contents+offset, this->length);
 	return resized;
 }
 
 
+bool
+Buffer::shiftLeft(size_t offset, size_t delta)
+{
+	auto	resized = false;
+
+	for (size_t i = offset; i < this->length; i++) {
+		this->contents[i] = this->contents[i+delta];
+	}
+
+	return this->Trim() != 0;
+}
+
+
+uint8_t&
+Buffer::operator[](size_t index)
+{
+	return this->contents[index];
+}
+
+
 } // namespace klib
diff --git a/Buffer.h b/Buffer.h
index df379f9..05c5f2f 100644
--- a/Buffer.h
+++ b/Buffer.h
@@ -14,19 +14,24 @@ namespace klib {
 class Buffer {
 public:
 	Buffer();
-	Buffer(size_t);
-	Buffer(const char *);
+	explicit Buffer(size_t);
+	explicit Buffer(const char *);
+	~Buffer() { this->Reclaim(); }
 
 	uint8_t	*Contents() { return this->contents; }
-	size_t	 Size() { return this->length; };
-	size_t	 Capacity() { return this->capacity; }
+	size_t	 Length() const { return this->length; };
+	size_t	 Capacity() const { return this->capacity; }
 
+	bool	 Append(const char *s);
 	bool	 Append(uint8_t *data, size_t datalen);
 	bool	 Append(uint8_t c);
+
+	bool	 Insert(size_t index, const char *s);
 	bool	 Insert(size_t index, uint8_t *data, size_t datalen);
 	bool	 Insert(size_t index, uint8_t c);
 
-	// bool	 Remove(size_t index, size_t length);
+	bool	 Remove(size_t index, size_t count);
+	bool	 Remove(size_t index); // remove single char
 
 	/* memory management */
 	void	 Resize(size_t newCapacity);
@@ -34,15 +39,19 @@ public:
 	void	 Clear();
 	void	 Reclaim();
 
+	uint8_t	&operator[](size_t index);
 private:
 	size_t	 mustGrow(size_t delta);
-	bool	 shift(size_t offset, size_t delta);
+	bool	 shiftRight(size_t offset, size_t delta);
+	bool	 shiftLeft(size_t offset, size_t delta);
 
 	uint8_t	*contents;
 	size_t	 length;
 	size_t	 capacity;
 };
 
+
+
 } // namespace klib
 
 #endif //KGE_BUFFER_H
diff --git a/bufferTest.cc b/bufferTest.cc
index e075b94..b1ebab6 100644
--- a/bufferTest.cc
+++ b/bufferTest.cc
@@ -11,6 +11,19 @@ main()
 	std::cout << buffer.Contents() << std::endl;
 
 	buffer.Insert(1, (uint8_t *)"el", 2);
+	buffer.Append('!');
 
 	std::cout << buffer.Contents() << std::endl;
+
+	buffer.Remove(buffer.Length()-1);
+	buffer.Remove(0, 5);
+	buffer.Insert(0, 'g');
+	buffer.Insert(1, (uint8_t *)"oodbye", 6);
+
+	buffer.Reclaim();
+	buffer.Append("and now for something completely different...");
+
+	std::cout << buffer.Contents() << std::endl;
+
+	return 0;
 }