1 files changed, 85 insertions, 0 deletions
diff --git a/src/base/buffers.c b/src/base/buffers.c
new file mode 100644
index 0000000..9e14092
--- /dev/null
+++ b/src/base/buffers.c
@@ -0,0 +1,85 @@
+/**
+ * \file   buffers.c
+ * \brief  Shared working buffer system.
+ * \author Copyright (c) 2007-2007 Jason Perkins and the Premake project
+ * 
+ * \note I need to do a lot of string building operations in Premake. Rather than
+ * constantly creating, resizing, and releasing (and forgetting to release)
+ * dynamic string buffers, I use this shared buffer pool instead. Each request
+ * to buffer_next() returns the next buffer in the list. Pointers to the buffers 
+ * can be safely passed around, and I don't need to remember to release anything 
+ * when I'm done. The buffers should only be used for transient values, obviously.
+ * If you need to keep a value around for any length of time copy it to a string.
+ *
+ * \note The size and number of the buffers is arbitrary; I just picked some numbers
+ * that seemed big enough.
+ */
+
+#include <stdlib.h>
+#include "premake.h"
+#include "base/buffers.h"
+
+/** The size of an individual buffer, in bytes. */
+const int BUFFER_SIZE = 0x4000;
+
+/** The number of buffers stored in the pool */
+static const int NUM_BUFFERS = 64;
+
+/** The pool of buffers */
+static char** buffers = NULL;
+
+/** The index of the next available buffer */
+static int next = 0;
+
+
+/**
+ * Clean up after the buffer system. Called by atexit().
+ */
+static void buffers_destroy(void)
+{
+	if (buffers != NULL)
+	{
+		int i;
+		for (i = 0; i < NUM_BUFFERS; ++i)
+		{
+			free(buffers[i]);
+		}
+		free(buffers);
+	}
+}
+
+
+/**
+ * Initialize the buffer system.
+ */
+static void buffers_create(void)
+{
+	int i;
+	buffers = (char**)malloc(sizeof(char*) * NUM_BUFFERS);
+	for (i = 0; i < NUM_BUFFERS; ++i)
+	{
+		buffers[i] = (char*)malloc(BUFFER_SIZE);
+	}
+	next = 0;
+	atexit(buffers_destroy);
+}
+
+
+/**
+ * Get a clean buffer.
+ * \returns An empty buffer.
+ */
+char * buffers_next()
+{
+	/* if this is the first call, initialize the buffer system */
+	if (buffers == NULL)
+		buffers_create();
+
+	next++;
+	if (next == NUM_BUFFERS)
+		next = 0;
+
+	/* initialize new buffers to empty string */
+	buffers[next][0] = '\0';
+	return buffers[next];
+}