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-rw-r--r--lib/zlib_inflate/infutil.c88
1 files changed, 88 insertions, 0 deletions
diff --git a/lib/zlib_inflate/infutil.c b/lib/zlib_inflate/infutil.c
new file mode 100644
index 00000000000..00202b3438e
--- /dev/null
+++ b/lib/zlib_inflate/infutil.c
@@ -0,0 +1,88 @@
+/* inflate_util.c -- data and routines common to blocks and codes
+ * Copyright (C) 1995-1998 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#include <linux/zutil.h>
+#include "infblock.h"
+#include "inftrees.h"
+#include "infcodes.h"
+#include "infutil.h"
+
+struct inflate_codes_state;
+
+/* And'ing with mask[n] masks the lower n bits */
+uInt zlib_inflate_mask[17] = {
+ 0x0000,
+ 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
+ 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
+};
+
+
+/* copy as much as possible from the sliding window to the output area */
+int zlib_inflate_flush(
+ inflate_blocks_statef *s,
+ z_streamp z,
+ int r
+)
+{
+ uInt n;
+ Byte *p;
+ Byte *q;
+
+ /* local copies of source and destination pointers */
+ p = z->next_out;
+ q = s->read;
+
+ /* compute number of bytes to copy as far as end of window */
+ n = (uInt)((q <= s->write ? s->write : s->end) - q);
+ if (n > z->avail_out) n = z->avail_out;
+ if (n && r == Z_BUF_ERROR) r = Z_OK;
+
+ /* update counters */
+ z->avail_out -= n;
+ z->total_out += n;
+
+ /* update check information */
+ if (s->checkfn != NULL)
+ z->adler = s->check = (*s->checkfn)(s->check, q, n);
+
+ /* copy as far as end of window */
+ memcpy(p, q, n);
+ p += n;
+ q += n;
+
+ /* see if more to copy at beginning of window */
+ if (q == s->end)
+ {
+ /* wrap pointers */
+ q = s->window;
+ if (s->write == s->end)
+ s->write = s->window;
+
+ /* compute bytes to copy */
+ n = (uInt)(s->write - q);
+ if (n > z->avail_out) n = z->avail_out;
+ if (n && r == Z_BUF_ERROR) r = Z_OK;
+
+ /* update counters */
+ z->avail_out -= n;
+ z->total_out += n;
+
+ /* update check information */
+ if (s->checkfn != NULL)
+ z->adler = s->check = (*s->checkfn)(s->check, q, n);
+
+ /* copy */
+ memcpy(p, q, n);
+ p += n;
+ q += n;
+ }
+
+ /* update pointers */
+ z->next_out = p;
+ s->read = q;
+
+ /* done */
+ return r;
+}