ref: ccef38fb998fc1d0c627ed4fb3cef2b5a83bf3ee
parent: 73eac9f95f513260a106f10cf9f8501ccc7eb36c
author: Alex Mayfield <alexmax2742@gmail.com>
date: Sun Feb 12 19:36:13 EST 2017
Implement a buffer for the TCP stream to go into
--- /dev/null
+++ b/midiproc/buffer.c
@@ -1,0 +1,137 @@
+//
+// Copyright(C) 2017 Alex Mayfield
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License
+// as published by the Free Software Foundation; either version 2
+// of the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// DESCRIPTION:
+// A simple buffer and reader implementation.
+//
+
+#include "buffer.h"
+
+//
+// Create a new buffer.
+//
+buffer_t *NewBuffer()
+{+ buffer_t *buf = malloc(sizeof(buffer_t));
+
+ buf->buffer_end = buf->buffer + BUFFER_SIZE;
+ Buffer_Clear(buf);
+
+ return buf;
+}
+
+//
+// Free a buffer.
+//
+void DeleteBuffer(buffer_t* buf)
+{+ free(buf);
+}
+
+//
+// Return the data in the buffer.
+//
+int Buffer_Data(buffer_t *buf, byte **data)
+{+ *data = buf->data;
+ return buf->data_len;
+}
+
+//
+// Push data onto the end of the buffer.
+//
+boolean Buffer_Push(buffer_t *buf, const void *data, int len)
+{+ if (len <= 0)
+ {+ return true;
+ }
+
+ ptrdiff_t space_begin = buf->data - buf->buffer;
+ ptrdiff_t space_end = buf->buffer_end - buf->data_end;
+
+ if (len > space_end)
+ {+ if (len > space_begin + space_end)
+ {+ // Don't overflow the buffer.
+ return false;
+ }
+
+ // Move our data to the front of the buffer.
+ memmove(buf->buffer, buf->data, buf->data_len);
+ buf->data = buf->buffer;
+ buf->data_end = buf->buffer + buf->data_len;
+ }
+
+ // Append to the buffer.
+ memcpy(buf->data_end, data, len);
+ buf->data_len += len;
+ buf->data_end = buf->data + buf->data_len;
+
+ return true;
+}
+
+
+//
+// Shift len bytes off of the front of the buffer.
+//
+void Buffer_Shift(buffer_t *buf, int len)
+{+ if (len <= 0)
+ {+ return;
+ }
+
+ ptrdiff_t max_shift = buf->data_end - buf->data;
+ if (len >= max_shift)
+ {+ Buffer_Clear(buf);
+ }
+ else
+ {+ buf->data += len;
+ buf->data_len -= len;
+ }
+}
+
+//
+// Clear the buffer.
+//
+void Buffer_Clear(buffer_t *buf)
+{+ buf->data = buf->buffer;
+ buf->data_end = buf->buffer;
+ buf->data_len = 0;
+}
+
+//
+// Create a new buffer reader
+//
+buffer_reader_t *NewReader(buffer_t* buffer)
+{+ buffer_reader_t *reader = malloc(sizeof(buffer_reader_t));
+
+ reader->buffer = buffer;
+ reader->pos = 0;
+
+ return reader;
+}
+
+//
+// Delete a buffer reader
+//
+void DeleteReader(buffer_reader_t *reader)
+{+ free(reader);
+}
--- /dev/null
+++ b/midiproc/buffer.h
@@ -1,0 +1,46 @@
+//
+// Copyright(C) 2017 Alex Mayfield
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License
+// as published by the Free Software Foundation; either version 2
+// of the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// DESCRIPTION:
+// A simple buffer and reader implementation.
+//
+
+#ifndef __BUFFER__
+#define __BUFFER__
+
+#include "../src/doomtype.h"
+
+#define BUFFER_SIZE 1024
+
+typedef struct {+ byte buffer[BUFFER_SIZE]; // Buffer.
+ byte* buffer_end; // End of Buffer.
+ byte* data; // Start of actual data.
+ byte* data_end; // End of actual data.
+ int data_len; // Length of actual data.
+} buffer_t;
+
+typedef struct {+ buffer_t *buffer;
+ int pos;
+} buffer_reader_t;
+
+buffer_t *NewBuffer();
+void DeleteBuffer(buffer_t* buf);
+int Buffer_Data(buffer_t *buf, byte **data);
+boolean Buffer_Push(buffer_t *buf, const void *data, int len);
+void Buffer_Shift(buffer_t *buf, int len);
+void Buffer_Clear(buffer_t *buf);
+
+#endif
+