1 files changed, 122 insertions, 0 deletions
diff --git a/base/gsdsrc.c b/base/gsdsrc.c
new file mode 100644
index 00000000..2cd28871
--- /dev/null
+++ b/base/gsdsrc.c
@@ -0,0 +1,122 @@
+/* Copyright (C) 2001-2019 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 the license contained in the file LICENSE in this distribution.
+
+   Refer to licensing information at http://www.artifex.com or contact
+   Artifex Software, Inc.,  1305 Grant Avenue - Suite 200, Novato,
+   CA 94945, U.S.A., +1(415)492-9861, for further information.
+*/
+
+
+/* DataSource procedures */
+
+#include "memory_.h"
+#include "gx.h"
+#include "gsdsrc.h"
+#include "gserrors.h"
+#include "stream.h"
+
+/* GC descriptor */
+public_st_data_source();
+static
+ENUM_PTRS_WITH(data_source_enum_ptrs, gs_data_source_t *psrc)
+{
+    if (psrc->type == data_source_type_string)
+        ENUM_RETURN_CONST_STRING_PTR(gs_data_source_t, data.str);
+    else if (psrc->type == data_source_type_stream)
+        ENUM_RETURN_PTR(gs_data_source_t, data.strm);
+    else			/* bytes or floats */
+        ENUM_RETURN_PTR(gs_data_source_t, data.str.data);
+}
+ENUM_PTRS_END
+static RELOC_PTRS_WITH(data_source_reloc_ptrs, gs_data_source_t *psrc)
+{
+    if (psrc->type == data_source_type_string)
+        RELOC_CONST_STRING_PTR(gs_data_source_t, data.str);
+    else if (psrc->type == data_source_type_stream)
+        RELOC_PTR(gs_data_source_t, data.strm);
+    else			/* bytes or floats */
+        RELOC_PTR(gs_data_source_t, data.str.data);
+}
+RELOC_PTRS_END
+
+/* Access data from a string or a byte object. */
+/* Does check bounds, and returns 0 data oob. Spec calls for rangecheck,
+   but CPSI implementation silently gives (bogus) data. */
+int
+data_source_access_string(const gs_data_source_t * psrc, ulong start,
+                          uint length, byte * buf, const byte ** ptr)
+{
+    const byte *p = psrc->data.str.data + start;
+
+    if (start + length <= psrc->data.str.size) {
+        if (ptr)
+            *ptr = p;
+        else
+            memcpy(buf, p, length);
+    } else {
+        if (start < psrc->data.str.size) {
+            uint oklen = psrc->data.str.size - start;
+            memcpy(buf, p, oklen);
+            memset(buf + oklen, 0, length - oklen);
+        } else {
+            memset(buf, 0, length);
+        }
+        *ptr = buf;
+    }
+    return 0;
+}
+/* access_bytes is identical to access_string, but has a different */
+/* GC procedure. */
+int
+data_source_access_bytes(const gs_data_source_t * psrc, ulong start,
+                         uint length, byte * buf, const byte ** ptr)
+{
+    const byte *p = psrc->data.str.data + start;
+
+    if (ptr)
+        *ptr = p;
+    else
+        memcpy(buf, p, length);
+    return 0;
+}
+
+/* Access data from a stream. */
+/* Returns gs_error_rangecheck if out of bounds. */
+int
+data_source_access_stream(const gs_data_source_t * psrc, ulong start,
+                          uint length, byte * buf, const byte ** ptr)
+{
+    stream *s = psrc->data.strm;
+    const byte *p;
+
+    if (start >= s->position &&
+        (p = start - s->position + s->cbuf) + length <=
+        s->cursor.r.limit + 1
+        ) {
+        if (ptr)
+            *ptr = p;
+        else
+            memcpy(buf, p, length);
+    } else {
+        uint nread;
+        int code = sseek(s, start);
+
+        if (code < 0)
+            return_error(gs_error_rangecheck);
+        code = sgets(s, buf, length, &nread);
+        if (code < 0)
+            return_error(gs_error_rangecheck);
+        if (nread != length)
+            return_error(gs_error_rangecheck);
+        if (ptr)
+            *ptr = buf;
+    }
+    return 0;
+}