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-rw-r--r--src/lzf_d.c191
1 files changed, 191 insertions, 0 deletions
diff --git a/src/lzf_d.c b/src/lzf_d.c
new file mode 100644
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--- /dev/null
+++ b/src/lzf_d.c
@@ -0,0 +1,191 @@
+/*
+ * Copyright (c) 2000-2010 Marc Alexander Lehmann <schmorp@schmorp.de>
+ *
+ * Redistribution and use in source and binary forms, with or without modifica-
+ * tion, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
+ * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
+ * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
+ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License ("GPL") version 2 or any later version,
+ * in which case the provisions of the GPL are applicable instead of
+ * the above. If you wish to allow the use of your version of this file
+ * only under the terms of the GPL and not to allow others to use your
+ * version of this file under the BSD license, indicate your decision
+ * by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL. If you do not delete the
+ * provisions above, a recipient may use your version of this file under
+ * either the BSD or the GPL.
+ */
+
+#include "lzfP.h"
+
+#if AVOID_ERRNO
+# define SET_ERRNO(n)
+#else
+# include <errno.h>
+# define SET_ERRNO(n) errno = (n)
+#endif
+
+#if USE_REP_MOVSB /* small win on amd, big loss on intel */
+#if (__i386 || __amd64) && __GNUC__ >= 3
+# define lzf_movsb(dst, src, len) \
+ asm ("rep movsb" \
+ : "=D" (dst), "=S" (src), "=c" (len) \
+ : "0" (dst), "1" (src), "2" (len));
+#endif
+#endif
+
+#if defined(__GNUC__) && __GNUC__ >= 7
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wimplicit-fallthrough"
+#endif
+size_t
+lzf_decompress (const void *const in_data, size_t in_len,
+ void *out_data, size_t out_len)
+{
+ u8 const *ip = (const u8 *)in_data;
+ u8 *op = (u8 *)out_data;
+ u8 const *const in_end = ip + in_len;
+ u8 *const out_end = op + out_len;
+
+ while (ip < in_end)
+ {
+ unsigned int ctrl;
+ ctrl = *ip++;
+
+ if (ctrl < (1 << 5)) /* literal run */
+ {
+ ctrl++;
+
+ if (op + ctrl > out_end)
+ {
+ SET_ERRNO (E2BIG);
+ return 0;
+ }
+
+#if CHECK_INPUT
+ if (ip + ctrl > in_end)
+ {
+ SET_ERRNO (EINVAL);
+ return 0;
+ }
+#endif
+
+#ifdef lzf_movsb
+ lzf_movsb (op, ip, ctrl);
+#else
+ switch (ctrl)
+ {
+ case 32: *op++ = *ip++; case 31: *op++ = *ip++; case 30: *op++ = *ip++; case 29: *op++ = *ip++;
+ case 28: *op++ = *ip++; case 27: *op++ = *ip++; case 26: *op++ = *ip++; case 25: *op++ = *ip++;
+ case 24: *op++ = *ip++; case 23: *op++ = *ip++; case 22: *op++ = *ip++; case 21: *op++ = *ip++;
+ case 20: *op++ = *ip++; case 19: *op++ = *ip++; case 18: *op++ = *ip++; case 17: *op++ = *ip++;
+ case 16: *op++ = *ip++; case 15: *op++ = *ip++; case 14: *op++ = *ip++; case 13: *op++ = *ip++;
+ case 12: *op++ = *ip++; case 11: *op++ = *ip++; case 10: *op++ = *ip++; case 9: *op++ = *ip++;
+ case 8: *op++ = *ip++; case 7: *op++ = *ip++; case 6: *op++ = *ip++; case 5: *op++ = *ip++;
+ case 4: *op++ = *ip++; case 3: *op++ = *ip++; case 2: *op++ = *ip++; case 1: *op++ = *ip++;
+ }
+#endif
+ }
+ else /* back reference */
+ {
+ unsigned int len = ctrl >> 5;
+
+ u8 *ref = op - ((ctrl & 0x1f) << 8) - 1;
+
+#if CHECK_INPUT
+ if (ip >= in_end)
+ {
+ SET_ERRNO (EINVAL);
+ return 0;
+ }
+#endif
+ if (len == 7)
+ {
+ len += *ip++;
+#if CHECK_INPUT
+ if (ip >= in_end)
+ {
+ SET_ERRNO (EINVAL);
+ return 0;
+ }
+#endif
+ }
+
+ ref -= *ip++;
+
+ if (op + len + 2 > out_end)
+ {
+ SET_ERRNO (E2BIG);
+ return 0;
+ }
+
+ if (ref < (u8 *)out_data)
+ {
+ SET_ERRNO (EINVAL);
+ return 0;
+ }
+
+#ifdef lzf_movsb
+ len += 2;
+ lzf_movsb (op, ref, len);
+#else
+ switch (len)
+ {
+ default:
+ len += 2;
+
+ if (op >= ref + len)
+ {
+ /* disjunct areas */
+ memcpy (op, ref, len);
+ op += len;
+ }
+ else
+ {
+ /* overlapping, use octte by octte copying */
+ do
+ *op++ = *ref++;
+ while (--len);
+ }
+
+ break;
+
+ case 9: *op++ = *ref++; /* fall-thru */
+ case 8: *op++ = *ref++; /* fall-thru */
+ case 7: *op++ = *ref++; /* fall-thru */
+ case 6: *op++ = *ref++; /* fall-thru */
+ case 5: *op++ = *ref++; /* fall-thru */
+ case 4: *op++ = *ref++; /* fall-thru */
+ case 3: *op++ = *ref++; /* fall-thru */
+ case 2: *op++ = *ref++; /* fall-thru */
+ case 1: *op++ = *ref++; /* fall-thru */
+ case 0: *op++ = *ref++; /* two octets more */
+ *op++ = *ref++; /* fall-thru */
+ }
+#endif
+ }
+ }
+
+ return op - (u8 *)out_data;
+}
+#if defined(__GNUC__) && __GNUC__ >= 5
+#pragma GCC diagnostic pop
+#endif