1 files changed, 106 insertions, 0 deletions
diff --git a/gs/base/gsdfilt.c b/gs/base/gsdfilt.c
new file mode 100644
index 000000000..ff5e7d3d5
--- /dev/null
+++ b/gs/base/gsdfilt.c
@@ -0,0 +1,106 @@
+/* Copyright (C) 2001-2006 Artifex Software, Inc.
+   All Rights Reserved.
+  
+   This software is provided AS-IS with no warranty, either express or
+   implied.
+
+   This software is distributed under license and may not be copied, modified
+   or distributed except as expressly authorized under the terms of that
+   license.  Refer to licensing information at http://www.artifex.com/
+   or contact Artifex Software, Inc.,  7 Mt. Lassen Drive - Suite A-134,
+   San Rafael, CA  94903, U.S.A., +1(415)492-9861, for further information.
+*/
+/* $Id$ */
+/* Functions for managing the device filter stack */
+
+#include "ctype_.h"
+#include "memory_.h"		/* for memchr, memcpy */
+#include "string_.h"
+#include "gx.h"
+#include "gp.h"
+#include "gscdefs.h"		/* for gs_lib_device_list */
+#include "gserrors.h"
+#include "gsfname.h"
+#include "gsstruct.h"
+#include "gspath.h"		/* gs_initclip prototype */
+#include "gspaint.h"		/* gs_erasepage prototype */
+#include "gsmatrix.h"		/* for gscoord.h */
+#include "gscoord.h"		/* for gs_initmatrix */
+#include "gzstate.h"
+#include "gxcmap.h"
+#include "gxdevice.h"
+#include "gxdevmem.h"
+#include "gxiodev.h"
+
+#include "gsdfilt.h"
+
+gs_private_st_ptrs3(st_gs_device_filter_stack, gs_device_filter_stack_t,
+		    "gs_device_filter_stack",
+		    gs_device_filter_stack_enum_ptrs,
+		    gs_device_filter_stack_reloc_ptrs,
+		    next, df, next_device);
+
+gs_public_st_simple(st_gs_device_filter, gs_device_filter_t,
+		    "gs_device_filter");
+
+int
+gs_push_device_filter(gs_memory_t *mem, gs_state *pgs, gs_device_filter_t *df)
+{
+    gs_device_filter_stack_t *dfs;
+    gx_device *new_dev = NULL;
+    int code;
+
+    dfs = gs_alloc_struct(mem, gs_device_filter_stack_t,
+			  &st_gs_device_filter_stack, "gs_push_device_filter");
+    if (dfs == NULL)
+	return_error(gs_error_VMerror);
+    rc_increment(pgs->device);
+    dfs->next_device = pgs->device;
+    code = df->push(df, mem, pgs, &new_dev, pgs->device);
+    if (code < 0) {
+	gs_free_object(mem, dfs, "gs_push_device_filter");
+	return code;
+    }
+    dfs->next = pgs->dfilter_stack;
+    pgs->dfilter_stack = dfs;
+    dfs->df = df;
+    rc_init(dfs, mem, 1);
+    gs_setdevice_no_init(pgs, new_dev);
+    rc_decrement_only(new_dev, "gs_push_device_filter");
+    return code;
+}
+
+int
+gs_pop_device_filter(gs_memory_t *mem, gs_state *pgs)
+{
+    gs_device_filter_stack_t *dfs_tos = pgs->dfilter_stack;
+    gx_device *tos_device = pgs->device;
+    gs_device_filter_t *df;
+    int code;
+
+    if (dfs_tos == NULL)
+	return_error(gs_error_rangecheck);
+    df = dfs_tos->df;
+    pgs->dfilter_stack = dfs_tos->next;
+    code = df->prepop(df, mem, pgs, tos_device);
+    rc_increment(tos_device);
+    gs_setdevice_no_init(pgs, dfs_tos->next_device);
+    rc_decrement_only(dfs_tos->next_device, "gs_pop_device_filter");
+    dfs_tos->df = NULL;
+    rc_decrement_only(dfs_tos, "gs_pop_device_filter");
+    code = df->postpop(df, mem, pgs, tos_device);
+    rc_decrement_only(tos_device, "gs_pop_device_filter");
+    return code;
+}
+
+int
+gs_clear_device_filters(gs_memory_t *mem, gs_state *pgs)
+{
+    int code;
+
+    while (pgs->dfilter_stack != NULL) {
+	if ((code = gs_pop_device_filter(mem, pgs)) < 0)
+	    return code;
+    }
+    return 0;
+}