diff --git a/debug.h b/debug.h
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--- /dev/null
+++ b/debug.h
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+/*
+  Copyright 2013 Google LLC All rights reserved.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at:
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+*/
+
+/*
+   american fuzzy lop - debug / error handling macros
+   --------------------------------------------------
+
+   Written and maintained by Michal Zalewski <lcamtuf@google.com>
+*/
+
+#ifndef _HAVE_DEBUG_H
+#define _HAVE_DEBUG_H
+
+#include <errno.h>
+
+#include "types.h"
+#include "config.h"
+
+/*******************
+ * Terminal colors *
+ *******************/
+
+#ifdef USE_COLOR
+
+#  define cBLK "\x1b[0;30m"
+#  define cRED "\x1b[0;31m"
+#  define cGRN "\x1b[0;32m"
+#  define cBRN "\x1b[0;33m"
+#  define cBLU "\x1b[0;34m"
+#  define cMGN "\x1b[0;35m"
+#  define cCYA "\x1b[0;36m"
+#  define cLGR "\x1b[0;37m"
+#  define cGRA "\x1b[1;90m"
+#  define cLRD "\x1b[1;91m"
+#  define cLGN "\x1b[1;92m"
+#  define cYEL "\x1b[1;93m"
+#  define cLBL "\x1b[1;94m"
+#  define cPIN "\x1b[1;95m"
+#  define cLCY "\x1b[1;96m"
+#  define cBRI "\x1b[1;97m"
+#  define cRST "\x1b[0m"
+
+#  define bgBLK "\x1b[40m"
+#  define bgRED "\x1b[41m"
+#  define bgGRN "\x1b[42m"
+#  define bgBRN "\x1b[43m"
+#  define bgBLU "\x1b[44m"
+#  define bgMGN "\x1b[45m"
+#  define bgCYA "\x1b[46m"
+#  define bgLGR "\x1b[47m"
+#  define bgGRA "\x1b[100m"
+#  define bgLRD "\x1b[101m"
+#  define bgLGN "\x1b[102m"
+#  define bgYEL "\x1b[103m"
+#  define bgLBL "\x1b[104m"
+#  define bgPIN "\x1b[105m"
+#  define bgLCY "\x1b[106m"
+#  define bgBRI "\x1b[107m"
+
+#else
+
+#  define cBLK ""
+#  define cRED ""
+#  define cGRN ""
+#  define cBRN ""
+#  define cBLU ""
+#  define cMGN ""
+#  define cCYA ""
+#  define cLGR ""
+#  define cGRA ""
+#  define cLRD ""
+#  define cLGN ""
+#  define cYEL ""
+#  define cLBL ""
+#  define cPIN ""
+#  define cLCY ""
+#  define cBRI ""
+#  define cRST ""
+
+#  define bgBLK ""
+#  define bgRED ""
+#  define bgGRN ""
+#  define bgBRN ""
+#  define bgBLU ""
+#  define bgMGN ""
+#  define bgCYA ""
+#  define bgLGR ""
+#  define bgGRA ""
+#  define bgLRD ""
+#  define bgLGN ""
+#  define bgYEL ""
+#  define bgLBL ""
+#  define bgPIN ""
+#  define bgLCY ""
+#  define bgBRI ""
+
+#endif /* ^USE_COLOR */
+
+/*************************
+ * Box drawing sequences *
+ *************************/
+
+#ifdef FANCY_BOXES
+
+#  define SET_G1   "\x1b)0"       /* Set G1 for box drawing    */
+#  define RESET_G1 "\x1b)B"       /* Reset G1 to ASCII         */
+#  define bSTART   "\x0e"         /* Enter G1 drawing mode     */
+#  define bSTOP    "\x0f"         /* Leave G1 drawing mode     */
+#  define bH       "q"            /* Horizontal line           */
+#  define bV       "x"            /* Vertical line             */
+#  define bLT      "l"            /* Left top corner           */
+#  define bRT      "k"            /* Right top corner          */
+#  define bLB      "m"            /* Left bottom corner        */
+#  define bRB      "j"            /* Right bottom corner       */
+#  define bX       "n"            /* Cross                     */
+#  define bVR      "t"            /* Vertical, branch right    */
+#  define bVL      "u"            /* Vertical, branch left     */
+#  define bHT      "v"            /* Horizontal, branch top    */
+#  define bHB      "w"            /* Horizontal, branch bottom */
+
+#else
+
+#  define SET_G1   ""
+#  define RESET_G1 ""
+#  define bSTART   ""
+#  define bSTOP    ""
+#  define bH       "-"
+#  define bV       "|"
+#  define bLT      "+"
+#  define bRT      "+"
+#  define bLB      "+"
+#  define bRB      "+"
+#  define bX       "+"
+#  define bVR      "+"
+#  define bVL      "+"
+#  define bHT      "+"
+#  define bHB      "+"
+
+#endif /* ^FANCY_BOXES */
+
+/***********************
+ * Misc terminal codes *
+ ***********************/
+
+#define TERM_HOME     "\x1b[H"
+#define TERM_CLEAR    TERM_HOME "\x1b[2J"
+#define cEOL          "\x1b[0K"
+#define CURSOR_HIDE   "\x1b[?25l"
+#define CURSOR_SHOW   "\x1b[?25h"
+
+/************************
+ * Debug & error macros *
+ ************************/
+
+/* Just print stuff to the appropriate stream. */
+
+#ifdef MESSAGES_TO_STDOUT
+#  define SAYF(x...)    printf(x)
+#else 
+#  define SAYF(x...)    fprintf(stderr, x)
+#endif /* ^MESSAGES_TO_STDOUT */
+
+/* Show a prefixed warning. */
+
+#define WARNF(x...) do { \
+    SAYF(cYEL "[!] " cBRI "WARNING: " cRST x); \
+    SAYF(cRST "\n"); \
+  } while (0)
+
+/* Show a prefixed "doing something" message. */
+
+#define ACTF(x...) do { \
+    SAYF(cLBL "[*] " cRST x); \
+    SAYF(cRST "\n"); \
+  } while (0)
+
+/* Show a prefixed "success" message. */
+
+#define OKF(x...) do { \
+    SAYF(cLGN "[+] " cRST x); \
+    SAYF(cRST "\n"); \
+  } while (0)
+
+/* Show a prefixed fatal error message (not used in afl). */
+
+#define BADF(x...) do { \
+    SAYF(cLRD "\n[-] " cRST x); \
+    SAYF(cRST "\n"); \
+  } while (0)
+
+/* Die with a verbose non-OS fatal error message. */
+
+#define FATAL(x...) do { \
+    SAYF(bSTOP RESET_G1 CURSOR_SHOW cRST cLRD "\n[-] PROGRAM ABORT : " \
+         cBRI x); \
+    SAYF(cLRD "\n         Location : " cRST "%s(), %s:%u\n\n", \
+         __FUNCTION__, __FILE__, __LINE__); \
+    exit(1); \
+  } while (0)
+
+/* Die by calling abort() to provide a core dump. */
+
+#define ABORT(x...) do { \
+    SAYF(bSTOP RESET_G1 CURSOR_SHOW cRST cLRD "\n[-] PROGRAM ABORT : " \
+         cBRI x); \
+    SAYF(cLRD "\n    Stop location : " cRST "%s(), %s:%u\n\n", \
+         __FUNCTION__, __FILE__, __LINE__); \
+    abort(); \
+  } while (0)
+
+/* Die while also including the output of perror(). */
+
+#define PFATAL(x...) do { \
+    fflush(stdout); \
+    SAYF(bSTOP RESET_G1 CURSOR_SHOW cRST cLRD "\n[-]  SYSTEM ERROR : " \
+         cBRI x); \
+    SAYF(cLRD "\n    Stop location : " cRST "%s(), %s:%u\n", \
+         __FUNCTION__, __FILE__, __LINE__); \
+    SAYF(cLRD "       OS message : " cRST "%s\n", strerror(errno)); \
+    exit(1); \
+  } while (0)
+
+/* Die with FAULT() or PFAULT() depending on the value of res (used to
+   interpret different failure modes for read(), write(), etc). */
+
+#define RPFATAL(res, x...) do { \
+    if (res < 0) PFATAL(x); else FATAL(x); \
+  } while (0)
+
+/* Error-checking versions of read() and write() that call RPFATAL() as
+   appropriate. */
+
+#define ck_write(fd, buf, len, fn) do { \
+    u32 _len = (len); \
+    s32 _res = write(fd, buf, _len); \
+    if (_res != _len) RPFATAL(_res, "Short write to %s", fn); \
+  } while (0)
+
+#define ck_read(fd, buf, len, fn) do { \
+    u32 _len = (len); \
+    s32 _res = read(fd, buf, _len); \
+    if (_res != _len) RPFATAL(_res, "Short read from %s", fn); \
+  } while (0)
+
+#endif /* ! _HAVE_DEBUG_H */