1 files changed, 138 insertions, 0 deletions
diff --git a/ext/gd/libgd/gd_io_ss.c b/ext/gd/libgd/gd_io_ss.c
new file mode 100644
index 0000000..0275cdc
--- /dev/null
+++ b/ext/gd/libgd/gd_io_ss.c
@@ -0,0 +1,138 @@
+
+/*
+   * io_ss.c
+   *
+   * Implements the Source/Sink interface.
+   *
+   * As will all I/O modules, most functions are for local use only (called
+   * via function pointers in the I/O context).
+   *
+   * The Source/Sink model is the primary 'user' interface for alternate data
+   * sources; the IOCtx interface is intended (at least in version 1.5) to be
+   * used internally until it settles down a bit.
+   *
+   * This module just layers the Source/Sink interface on top of the IOCtx; no
+   * support is provided for tell/seek, so GD2 writing is not possible, and
+   * retrieving parts of GD2 files is also not possible.
+   *
+   * A new SS context does not need to be created with both a Source and a Sink.
+   *
+   * Written/Modified 1999, Philip Warner.
+   *
+ */
+
+#include <math.h>
+#include <string.h>
+#include <stdlib.h>
+#include "gd.h"
+#include "gdhelpers.h"
+
+/* this is used for creating images in main memory */
+
+typedef struct ssIOCtx
+{
+	gdIOCtx ctx;
+	gdSourcePtr src;
+	gdSinkPtr snk;
+} ssIOCtx;
+
+typedef struct ssIOCtx *ssIOCtxPtr;
+
+gdIOCtx *gdNewSSCtx (gdSourcePtr src, gdSinkPtr snk);
+
+static int sourceGetbuf (gdIOCtx *, void *, int);
+static int sourceGetchar (gdIOCtx * ctx);
+static int sinkPutbuf (gdIOCtx * ctx, const void *buf, int size);
+static void sinkPutchar (gdIOCtx * ctx, int a);
+static void gdFreeSsCtx (gdIOCtx * ctx);
+
+/* return data as a dynamic pointer */
+gdIOCtx * gdNewSSCtx (gdSourcePtr src, gdSinkPtr snk)
+{
+	ssIOCtxPtr ctx;
+
+	ctx = (ssIOCtxPtr) gdMalloc (sizeof (ssIOCtx));
+
+	ctx->src = src;
+	ctx->snk = snk;
+
+	ctx->ctx.getC = sourceGetchar;
+	ctx->ctx.getBuf = sourceGetbuf;
+
+	ctx->ctx.putC = sinkPutchar;
+	ctx->ctx.putBuf = sinkPutbuf;
+
+	ctx->ctx.tell = NULL;
+	ctx->ctx.seek = NULL;
+
+	ctx->ctx.gd_free = gdFreeSsCtx;
+
+	return (gdIOCtx *) ctx;
+}
+
+static void gdFreeSsCtx (gdIOCtx * ctx)
+{
+	gdFree(ctx);
+}
+
+
+static int sourceGetbuf (gdIOCtx * ctx, void *buf, int size)
+{
+	ssIOCtx *lctx;
+	int res;
+
+	lctx = (ssIOCtx *) ctx;
+
+	res = ((lctx->src->source) (lctx->src->context, buf, size));
+
+	/*
+	 * Translate the return values from the Source object:
+	 * 0 is EOF, -1 is error
+	 */
+
+	if (res == 0) {
+		return EOF;
+	} else if (res < 0) {
+		return 0;
+	} else {
+		return res;
+	}
+}
+
+static int sourceGetchar (gdIOCtx * ctx)
+{
+	int res;
+	unsigned char buf;
+
+	res = sourceGetbuf (ctx, &buf, 1);
+
+	if (res == 1) {
+		return buf;
+	} else {
+		return EOF;
+	}
+}
+
+static int sinkPutbuf (gdIOCtx * ctx, const void *buf, int size)
+{
+	ssIOCtxPtr lctx;
+	int res;
+
+	lctx = (ssIOCtx *) ctx;
+
+	res = (lctx->snk->sink) (lctx->snk->context, buf, size);
+
+	if (res <= 0) {
+		return 0;
+	} else {
+		return res;
+	}
+}
+
+static void sinkPutchar (gdIOCtx * ctx, int a)
+{
+	unsigned char b;
+
+	b = a;
+	sinkPutbuf (ctx, &b, 1);
+}