/*
   american fuzzy lop++ - LLVM-mode wrapper for clang
   ------------------------------------------------

   Written by Laszlo Szekeres <lszekeres@google.com> and
              Michal Zalewski

   LLVM integration design comes from Laszlo Szekeres.

   Copyright 2015, 2016 Google Inc. All rights reserved.
   Copyright 2019-2020 AFLplusplus Project. 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

   This program is a drop-in replacement for clang, similar in most respects
   to ../afl-gcc. It tries to figure out compilation mode, adds a bunch
   of flags, and then calls the real compiler.

 */

#define AFL_MAIN

#include "common.h"
#include "config.h"
#include "types.h"
#include "debug.h"
#include "alloc-inl.h"
#include "llvm-ngram-coverage.h"

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <limits.h>
#include <assert.h>

#include "llvm/Config/llvm-config.h"

static u8 * obj_path;                  /* Path to runtime libraries         */
static u8 **cc_params;                 /* Parameters passed to the real CC  */
static u32  cc_par_cnt = 1;            /* Param count, including argv0      */
static u8   llvm_fullpath[PATH_MAX];
static u8  instrument_mode, instrument_opt_mode, ngram_size, lto_mode, cpp_mode;
static u8 *lto_flag = AFL_CLANG_FLTO;
static u8  debug;
static u8  cwd[4096];
static u8  cmplog_mode;
u8         use_stdin = 0;                                          /* dummy */
// static u8 *march_opt = CFLAGS_OPT;

enum {

  INSTURMENT_DEFAULT = 0,
  INSTRUMENT_CLASSIC = 1,
  INSTRUMENT_AFL = 1,
  INSTRUMENT_PCGUARD = 2,
  INSTRUMENT_INSTRIM = 3,
  INSTRUMENT_CFG = 3,
  INSTRUMENT_LTO = 4,
  INSTRUMENT_OPT_CTX = 8,
  INSTRUMENT_OPT_NGRAM = 16

};

char instrument_mode_string[18][18] = {

    "DEFAULT", "CLASSIC", "PCGUARD", "CFG", "LTO", "", "",      "", "CTX", "",
    "",        "",        "",        "",    "",    "", "NGRAM", ""

};

u8 *getthecwd() {

  static u8 fail[] = "";
  if (getcwd(cwd, sizeof(cwd)) == NULL) return fail;
  return cwd;

}

/* Try to find the runtime libraries. If that fails, abort. */

static void find_obj(u8 *argv0) {

  u8 *afl_path = getenv("AFL_PATH");
  u8 *slash, *tmp;

  if (afl_path) {

#ifdef __ANDROID__
    tmp = alloc_printf("%s/afl-llvm-rt.so", afl_path);
#else
    tmp = alloc_printf("%s/afl-llvm-rt.o", afl_path);
#endif

    if (!access(tmp, R_OK)) {

      obj_path = afl_path;
      ck_free(tmp);
      return;

    }

    ck_free(tmp);

  }

  slash = strrchr(argv0, '/');

  if (slash) {

    u8 *dir;

    *slash = 0;
    dir = ck_strdup(argv0);
    *slash = '/';

#ifdef __ANDROID__
    tmp = alloc_printf("%s/afl-llvm-rt.so", dir);
#else
    tmp = alloc_printf("%s/afl-llvm-rt.o", dir);
#endif

    if (!access(tmp, R_OK)) {

      obj_path = dir;
      ck_free(tmp);
      return;

    }

    ck_free(tmp);
    ck_free(dir);

  }

#ifdef __ANDROID__
  if (!access(AFL_PATH "/afl-llvm-rt.so", R_OK)) {

#else
  if (!access(AFL_PATH "/afl-llvm-rt.o", R_OK)) {

#endif

    obj_path = AFL_PATH;
    return;

  }

  FATAL(
      "Unable to find 'afl-llvm-rt.o' or 'afl-llvm-pass.so'. Please set "
      "AFL_PATH");

}

/* Copy argv to cc_params, making the necessary edits. */

static void edit_params(u32 argc, char **argv, char **envp) {

  u8  fortify_set = 0, asan_set = 0, x_set = 0, bit_mode = 0;
  u8 *name;

  cc_params = ck_alloc((argc + 128) * sizeof(u8 *));

  name = strrchr(argv[0], '/');
  if (!name)
    name = argv[0];
  else
    ++name;

  if (lto_mode)
    if (lto_flag[0] != '-')
      FATAL(
          "Using afl-clang-lto is not possible because Makefile magic did not "
          "identify the correct -flto flag");

  if (!strcmp(name, "afl-clang-fast++") || !strcmp(name, "afl-clang-lto++") ||
      !strcmp(name, "afl-clang++")) {

    u8 *alt_cxx = getenv("AFL_CXX");
    if (USE_BINDIR)
      snprintf(llvm_fullpath, sizeof(llvm_fullpath), "%s/clang++", LLVM_BINDIR);
    else
      sprintf(llvm_fullpath, CLANGPP_BIN);
    cc_params[0] = alt_cxx && *alt_cxx ? alt_cxx : (u8 *)llvm_fullpath;
    cpp_mode = 1;

  } else if (!strcmp(name, "afl-clang-fast") ||

             !strcmp(name, "afl-clang-lto") || !strcmp(name, "afl-clang")) {

    u8 *alt_cc = getenv("AFL_CC");
    if (USE_BINDIR)
      snprintf(llvm_fullpath, sizeof(llvm_fullpath), "%s/clang", LLVM_BINDIR);
    else
      sprintf(llvm_fullpath, CLANG_BIN);
    cc_params[0] = alt_cc && *alt_cc ? alt_cc : (u8 *)llvm_fullpath;

  } else {

    fprintf(stderr, "Name of the binary: %s\n", argv[0]);
    FATAL(
        "Name of the binary is not a known name, expected afl-clang-fast(++) "
        "or afl-clang-lto(++)");

  }

  cc_params[cc_par_cnt++] = "-Wno-unused-command-line-argument";

  if (lto_mode && cpp_mode)
    cc_params[cc_par_cnt++] = "-lc++";  // needed by fuzzbench, early

  /* There are several ways to compile with afl-clang-fast. In the traditional
     mode, we use afl-llvm-pass.so, then there is libLLVMInsTrim.so which is
     faster and creates less map pollution.
     Then there is the 'trace-pc-guard' mode, we use native LLVM
     instrumentation callbacks instead. For trace-pc-guard see:
     http://clang.llvm.org/docs/SanitizerCoverage.html#tracing-pcs-with-guards
     The best instrumentatation is with the LTO modes, the classic and
     InsTrimLTO, the latter is faster. The LTO modes are activated by using
     afl-clang-lto(++)
   */

  if (lto_mode) {

    if (getenv("AFL_LLVM_INSTRUMENT_FILE") != NULL ||
        getenv("AFL_LLVM_WHITELIST")) {

      cc_params[cc_par_cnt++] = "-Xclang";
      cc_params[cc_par_cnt++] = "-load";
      cc_params[cc_par_cnt++] = "-Xclang";
      cc_params[cc_par_cnt++] =
          alloc_printf("%s/afl-llvm-lto-instrumentlist.so", obj_path);

    }

  }

  // laf
  if (getenv("LAF_SPLIT_SWITCHES") || getenv("AFL_LLVM_LAF_SPLIT_SWITCHES")) {

    cc_params[cc_par_cnt++] = "-Xclang";
    cc_params[cc_par_cnt++] = "-load";
    cc_params[cc_par_cnt++] = "-Xclang";
    cc_params[cc_par_cnt++] =
        alloc_printf("%s/split-switches-pass.so", obj_path);

  }

  if (getenv("LAF_TRANSFORM_COMPARES") ||
      getenv("AFL_LLVM_LAF_TRANSFORM_COMPARES")) {

    if (!be_quiet && getenv("AFL_LLVM_LTO_AUTODICTIONARY") && lto_mode)
      WARNF(
          "using AFL_LLVM_LAF_TRANSFORM_COMPARES together with "
          "AFL_LLVM_LTO_AUTODICTIONARY makes no sense. Use only "
          "AFL_LLVM_LTO_AUTODICTIONARY.");

    cc_params[cc_par_cnt++] = "-Xclang";
    cc_params[cc_par_cnt++] = "-load";
    cc_params[cc_par_cnt++] = "-Xclang";
    cc_params[cc_par_cnt++] =
        alloc_printf("%s/compare-transform-pass.so", obj_path);

  }

  if (getenv("LAF_SPLIT_COMPARES") || getenv("AFL_LLVM_LAF_SPLIT_COMPARES")) {

    cc_params[cc_par_cnt++] = "-Xclang";
    cc_params[cc_par_cnt++] = "-load";
    cc_params[cc_par_cnt++] = "-Xclang";
    cc_params[cc_par_cnt++] =
        alloc_printf("%s/split-compares-pass.so", obj_path);

  }

  // /laf

  unsetenv("AFL_LD");
  unsetenv("AFL_LD_CALLER");
  if (cmplog_mode) {

    cc_params[cc_par_cnt++] = "-Xclang";
    cc_params[cc_par_cnt++] = "-load";
    cc_params[cc_par_cnt++] = "-Xclang";
    cc_params[cc_par_cnt++] =
        alloc_printf("%s/cmplog-routines-pass.so", obj_path);

    // reuse split switches from laf
    cc_params[cc_par_cnt++] = "-Xclang";
    cc_params[cc_par_cnt++] = "-load";
    cc_params[cc_par_cnt++] = "-Xclang";
    cc_params[cc_par_cnt++] =
        alloc_printf("%s/split-switches-pass.so", obj_path);

    cc_params[cc_par_cnt++] = "-Xclang";
    cc_params[cc_par_cnt++] = "-load";
    cc_params[cc_par_cnt++] = "-Xclang";
    cc_params[cc_par_cnt++] =
        alloc_printf("%s/cmplog-instructions-pass.so", obj_path);

    cc_params[cc_par_cnt++] = "-fno-inline";

  }

  if (lto_mode) {

    cc_params[cc_par_cnt++] = alloc_printf("-fuse-ld=%s", AFL_REAL_LD);
    cc_params[cc_par_cnt++] = "-Wl,--allow-multiple-definition";
    if (instrument_mode == INSTRUMENT_CFG)
      cc_params[cc_par_cnt++] =
          alloc_printf("-Wl,-mllvm=-load=%s/afl-llvm-lto-instrim.so", obj_path);
    else
      cc_params[cc_par_cnt++] = alloc_printf(
          "-Wl,-mllvm=-load=%s/afl-llvm-lto-instrumentation.so", obj_path);
    cc_params[cc_par_cnt++] = lto_flag;

  } else {

    if (instrument_mode == INSTRUMENT_PCGUARD) {

      cc_params[cc_par_cnt++] =
          "-fsanitize-coverage=trace-pc-guard";  // edge coverage by default

    } else {

      cc_params[cc_par_cnt++] = "-Xclang";
      cc_params[cc_par_cnt++] = "-load";
      cc_params[cc_par_cnt++] = "-Xclang";
      if (instrument_mode == INSTRUMENT_CFG)
        cc_params[cc_par_cnt++] =
            alloc_printf("%s/libLLVMInsTrim.so", obj_path);
      else
        cc_params[cc_par_cnt++] = alloc_printf("%s/afl-llvm-pass.so", obj_path);

    }

  }

  // cc_params[cc_par_cnt++] = "-Qunused-arguments";

  // in case LLVM is installed not via a package manager or "make install"
  // e.g. compiled download or compiled from github then it's ./lib directory
  // might not be in the search path. Add it if so.
  u8 *libdir = strdup(LLVM_LIBDIR);
  if (cpp_mode && strlen(libdir) && strncmp(libdir, "/usr", 4) &&
      strncmp(libdir, "/lib", 4)) {

    cc_params[cc_par_cnt++] = "-rpath";
    cc_params[cc_par_cnt++] = libdir;

  } else {

    free(libdir);

  }

  /* Detect stray -v calls from ./configure scripts. */

  while (--argc) {

    u8 *cur = *(++argv);

    if (!strcmp(cur, "-m32")) bit_mode = 32;
    if (!strcmp(cur, "armv7a-linux-androideabi")) bit_mode = 32;
    if (!strcmp(cur, "-m64")) bit_mode = 64;

    if (!strcmp(cur, "-x")) x_set = 1;

    if (!strcmp(cur, "-fsanitize=address") || !strcmp(cur, "-fsanitize=memory"))
      asan_set = 1;

    if (strstr(cur, "FORTIFY_SOURCE")) fortify_set = 1;

    if (!strcmp(cur, "-Wl,-z,defs") || !strcmp(cur, "-Wl,--no-undefined"))
      continue;

    cc_params[cc_par_cnt++] = cur;

  }

  if (getenv("AFL_HARDEN")) {

    cc_params[cc_par_cnt++] = "-fstack-protector-all";

    if (!fortify_set) cc_params[cc_par_cnt++] = "-D_FORTIFY_SOURCE=2";

  }

  if (!asan_set) {

    if (getenv("AFL_USE_ASAN")) {

      if (getenv("AFL_USE_MSAN")) FATAL("ASAN and MSAN are mutually exclusive");

      if (getenv("AFL_HARDEN"))
        FATAL("ASAN and AFL_HARDEN are mutually exclusive");

      cc_params[cc_par_cnt++] = "-U_FORTIFY_SOURCE";
      cc_params[cc_par_cnt++] = "-fsanitize=address";

    } else if (getenv("AFL_USE_MSAN")) {

      if (getenv("AFL_USE_ASAN")) FATAL("ASAN and MSAN are mutually exclusive");

      if (getenv("AFL_HARDEN"))
        FATAL("MSAN and AFL_HARDEN are mutually exclusive");

      cc_params[cc_par_cnt++] = "-U_FORTIFY_SOURCE";
      cc_params[cc_par_cnt++] = "-fsanitize=memory";

    }

  }

  if (getenv("AFL_USE_UBSAN")) {

    cc_params[cc_par_cnt++] = "-fsanitize=undefined";
    cc_params[cc_par_cnt++] = "-fsanitize-undefined-trap-on-error";
    cc_params[cc_par_cnt++] = "-fno-sanitize-recover=all";

  }

  if (getenv("AFL_USE_CFISAN")) {

    if (!lto_mode) {

      uint32_t i = 0, found = 0;
      while (envp[i] != NULL && !found)
        if (strncmp("-flto", envp[i++], 5) == 0) found = 1;
      if (!found) cc_params[cc_par_cnt++] = "-flto";

    }

    cc_params[cc_par_cnt++] = "-fsanitize=cfi";
    cc_params[cc_par_cnt++] = "-fvisibility=hidden";

  }

  if (!getenv("AFL_DONT_OPTIMIZE")) {

    cc_params[cc_par_cnt++] = "-g";
    cc_params[cc_par_cnt++] = "-O3";
    cc_params[cc_par_cnt++] = "-funroll-loops";
    // if (strlen(march_opt) > 1 && march_opt[0] == '-')
    //  cc_params[cc_par_cnt++] = march_opt;

  }

  if (getenv("AFL_NO_BUILTIN") || getenv("AFL_LLVM_LAF_TRANSFORM_COMPARES") ||
      getenv("LAF_TRANSFORM_COMPARES") ||
      (lto_mode && (getenv("AFL_LLVM_LTO_AUTODICTIONARY") ||
                    getenv("AFL_LLVM_AUTODICTIONARY")))) {

    cc_params[cc_par_cnt++] = "-fno-builtin-strcmp";
    cc_params[cc_par_cnt++] = "-fno-builtin-strncmp";
    cc_params[cc_par_cnt++] = "-fno-builtin-strcasecmp";
    cc_params[cc_par_cnt++] = "-fno-builtin-strncasecmp";
    cc_params[cc_par_cnt++] = "-fno-builtin-memcmp";
    cc_params[cc_par_cnt++] = "-fno-builtin-bcmp";
    cc_params[cc_par_cnt++] = "-fno-builtin-strstr";
    cc_params[cc_par_cnt++] = "-fno-builtin-strcasestr";

  }

#if defined(USEMMAP) && !defined(__HAIKU__)
  cc_params[cc_par_cnt++] = "-lrt";
#endif

  cc_params[cc_par_cnt++] = "-D__AFL_HAVE_MANUAL_CONTROL=1";
  cc_params[cc_par_cnt++] = "-D__AFL_COMPILER=1";
  cc_params[cc_par_cnt++] = "-DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION=1";

  /* When the user tries to use persistent or deferred forkserver modes by
     appending a single line to the program, we want to reliably inject a
     signature into the binary (to be picked up by afl-fuzz) and we want
     to call a function from the runtime .o file. This is unnecessarily
     painful for three reasons:

     1) We need to convince the compiler not to optimize out the signature.
        This is done with __attribute__((used)).

     2) We need to convince the linker, when called with -Wl,--gc-sections,
        not to do the same. This is done by forcing an assignment to a
        'volatile' pointer.

     3) We need to declare __afl_persistent_loop() in the global namespace,
        but doing this within a method in a class is hard - :: and extern "C"
        are forbidden and __attribute__((alias(...))) doesn't work. Hence the
        __asm__ aliasing trick.

   */

  cc_params[cc_par_cnt++] =
      "-D__AFL_FUZZ_INIT()="
      "int __afl_sharedmem_fuzzing = 1;"
      "extern unsigned int *__afl_fuzz_len;"
      "extern unsigned char *__afl_fuzz_ptr;"
      "unsigned char *__afl_fuzz_alt_ptr;";
  cc_params[cc_par_cnt++] =
      "-D__AFL_FUZZ_TESTCASE_BUF=(__afl_fuzz_ptr ? __afl_fuzz_ptr : "
      "(__afl_fuzz_alt_ptr = (unsigned char *) malloc(1 * 1024 * 1024)))";
  cc_params[cc_par_cnt++] =
      "-D__AFL_FUZZ_TESTCASE_LEN=(__afl_fuzz_ptr ? *__afl_fuzz_len : read(0, "
      "__afl_fuzz_alt_ptr, 1 * 1024 * 1024))";

  cc_params[cc_par_cnt++] =
      "-D__AFL_LOOP(_A)="
      "({ static volatile char *_B __attribute__((used)); "
      " _B = (char*)\"" PERSIST_SIG
      "\"; "
#ifdef __APPLE__
      "__attribute__((visibility(\"default\"))) "
      "int _L(unsigned int) __asm__(\"___afl_persistent_loop\"); "
#else
      "__attribute__((visibility(\"default\"))) "
      "int _L(unsigned int) __asm__(\"__afl_persistent_loop\"); "
#endif                                                        /* ^__APPLE__ */
      "_L(_A); })";

  cc_params[cc_par_cnt++] =
      "-D__AFL_INIT()="
      "do { static volatile char *_A __attribute__((used)); "
      " _A = (char*)\"" DEFER_SIG
      "\"; "
#ifdef __APPLE__
      "__attribute__((visibility(\"default\"))) "
      "void _I(void) __asm__(\"___afl_manual_init\"); "
#else
      "__attribute__((visibility(\"default\"))) "
      "void _I(void) __asm__(\"__afl_manual_init\"); "
#endif                                                        /* ^__APPLE__ */
      "_I(); } while (0)";

  if (x_set) {

    cc_params[cc_par_cnt++] = "-x";
    cc_params[cc_par_cnt++] = "none";

  }

#ifndef __ANDROID__
  switch (bit_mode) {

    case 0:
      cc_params[cc_par_cnt++] = alloc_printf("%s/afl-llvm-rt.o", obj_path);
      if (lto_mode)
        cc_params[cc_par_cnt++] =
            alloc_printf("%s/afl-llvm-rt-lto.o", obj_path);
      break;

    case 32:
      cc_params[cc_par_cnt++] = alloc_printf("%s/afl-llvm-rt-32.o", obj_path);
      if (access(cc_params[cc_par_cnt - 1], R_OK))
        FATAL("-m32 is not supported by your compiler");
      if (lto_mode) {

        cc_params[cc_par_cnt++] =
            alloc_printf("%s/afl-llvm-rt-lto-32.o", obj_path);
        if (access(cc_params[cc_par_cnt - 1], R_OK))
          FATAL("-m32 is not supported by your compiler");

      }

      break;

    case 64:
      cc_params[cc_par_cnt++] = alloc_printf("%s/afl-llvm-rt-64.o", obj_path);
      if (access(cc_params[cc_par_cnt - 1], R_OK))
        FATAL("-m64 is not supported by your compiler");
      if (lto_mode) {

        cc_params[cc_par_cnt++] =
            alloc_printf("%s/afl-llvm-rt-lto-64.o", obj_path);
        if (access(cc_params[cc_par_cnt - 1], R_OK))
          FATAL("-m64 is not supported by your compiler");

      }

      break;

  }

#endif

  cc_params[cc_par_cnt] = NULL;

}

/* Main entry point */

int main(int argc, char **argv, char **envp) {

  int   i;
  char *callname = "afl-clang-fast", *ptr = NULL;

  if (getenv("AFL_DEBUG")) {

    debug = 1;
    if (strcmp(getenv("AFL_DEBUG"), "0") == 0) unsetenv("AFL_DEBUG");

  } else if (getenv("AFL_QUIET"))

    be_quiet = 1;

  if (getenv("USE_TRACE_PC") || getenv("AFL_USE_TRACE_PC") ||
      getenv("AFL_LLVM_USE_TRACE_PC") || getenv("AFL_TRACE_PC")) {

    if (instrument_mode == 0)
      instrument_mode = INSTRUMENT_PCGUARD;
    else if (instrument_mode != INSTRUMENT_PCGUARD)
      FATAL("you can not set AFL_LLVM_INSTRUMENT and AFL_TRACE_PC together");

  }

  if (getenv("AFL_LLVM_INSTRIM") || getenv("INSTRIM") ||
      getenv("INSTRIM_LIB")) {

    if (instrument_mode == 0)
      instrument_mode = INSTRUMENT_CFG;
    else if (instrument_mode != INSTRUMENT_CFG)
      FATAL(
          "you can not set AFL_LLVM_INSTRUMENT and AFL_LLVM_INSTRIM together");

  }

  if (getenv("AFL_LLVM_CTX")) instrument_opt_mode |= INSTRUMENT_OPT_CTX;

  if (getenv("AFL_LLVM_NGRAM_SIZE")) {

    instrument_opt_mode |= INSTRUMENT_OPT_NGRAM;
    ngram_size = atoi(getenv("AFL_LLVM_NGRAM_SIZE"));
    if (ngram_size < 2 || ngram_size > NGRAM_SIZE_MAX)
      FATAL(
          "NGRAM instrumentation mode must be between 2 and NGRAM_SIZE_MAX "
          "(%u)",
          NGRAM_SIZE_MAX);

  }

  if (getenv("AFL_LLVM_INSTRUMENT")) {

    u8 *ptr = strtok(getenv("AFL_LLVM_INSTRUMENT"), ":,;");

    while (ptr) {

      if (strncasecmp(ptr, "afl", strlen("afl")) == 0 ||
          strncasecmp(ptr, "classic", strlen("classic")) == 0) {

        if (!instrument_mode || instrument_mode == INSTRUMENT_AFL)
          instrument_mode = INSTRUMENT_AFL;
        else
          FATAL("main instrumentation mode already set with %s",
                instrument_mode_string[instrument_mode]);

      }

      if (strncasecmp(ptr, "pc-guard", strlen("pc-guard")) == 0 ||
          strncasecmp(ptr, "pcguard", strlen("pcgard")) == 0) {

        if (!instrument_mode || instrument_mode == INSTRUMENT_PCGUARD)
          instrument_mode = INSTRUMENT_PCGUARD;
        else
          FATAL("main instrumentation mode already set with %s",
                instrument_mode_string[instrument_mode]);

      }

      if (strncasecmp(ptr, "cfg", strlen("cfg")) == 0 ||
          strncasecmp(ptr, "instrim", strlen("instrim")) == 0) {

        if (instrument_mode == INSTRUMENT_LTO) {

          instrument_mode = INSTRUMENT_CFG;
          lto_mode = 1;

        } else if (!instrument_mode || instrument_mode == INSTRUMENT_CFG)

          instrument_mode = INSTRUMENT_CFG;
        else
          FATAL("main instrumentation mode already set with %s",
                instrument_mode_string[instrument_mode]);

      }

      if (strncasecmp(ptr, "lto", strlen("lto")) == 0) {

        lto_mode = 1;
        if (!instrument_mode || instrument_mode == INSTRUMENT_LTO)
          instrument_mode = INSTRUMENT_LTO;
        else if (instrument_mode != INSTRUMENT_CFG)
          FATAL("main instrumentation mode already set with %s",
                instrument_mode_string[instrument_mode]);

      }

      if (strncasecmp(ptr, "ctx", strlen("ctx")) == 0) {

        instrument_opt_mode |= INSTRUMENT_OPT_CTX;
        setenv("AFL_LLVM_CTX", "1", 1);

      }

      if (strncasecmp(ptr, "ngram", strlen("ngram")) == 0) {

        ptr += strlen("ngram");
        while (*ptr && (*ptr < '0' || *ptr > '9'))
          ptr++;
        if (!*ptr)
          if ((ptr = getenv("AFL_LLVM_NGRAM_SIZE")) != NULL)
            FATAL(
                "you must set the NGRAM size with (e.g. for value 2) "
                "AFL_LLVM_INSTRUMENT=ngram-2");
        ngram_size = atoi(ptr);
        if (ngram_size < 2 || ngram_size > NGRAM_SIZE_MAX)
          FATAL(
              "NGRAM instrumentation option must be between 2 and "
              "NGRAM_SIZE_MAX "
              "(%u)",
              NGRAM_SIZE_MAX);
        instrument_opt_mode |= (INSTRUMENT_OPT_NGRAM);
        ptr = alloc_printf("%u", ngram_size);
        setenv("AFL_LLVM_NGRAM_SIZE", ptr, 1);

      }

      ptr = strtok(NULL, ":,;");

    }

  }

  if (strstr(argv[0], "afl-clang-lto") != NULL) {

    if (instrument_mode == 0 || instrument_mode == INSTRUMENT_LTO ||
        instrument_mode == INSTRUMENT_CFG) {

      lto_mode = 1;
      callname = "afl-clang-lto";
      if (!instrument_mode) {

        instrument_mode = INSTRUMENT_LTO;
        ptr = instrument_mode_string[instrument_mode];

      }

    } else {

      if (!be_quiet)
        WARNF("afl-clang-lto called with mode %s, using that mode instead",
              instrument_mode_string[instrument_mode]);

    }

  }

  if (instrument_mode == 0) {

#if LLVM_VERSION_MAJOR <= 6
    instrument_mode = INSTRUMENT_AFL;
#else
    if (getenv("AFL_LLVM_INSTRUMENT_FILE") || getenv("AFL_LLVM_WHITELIST"))
      instrument_mode = INSTRUMENT_AFL;
    else
      instrument_mode = INSTRUMENT_PCGUARD;
#endif

  }

  if (instrument_opt_mode && lto_mode)
    FATAL(
        "CTX and NGRAM can not be used in LTO mode (and would make LTO "
        "useless)");

  if (!instrument_opt_mode) {

    if (lto_mode && instrument_mode == INSTRUMENT_CFG)
      ptr = alloc_printf("InsTrimLTO");
    else
      ptr = instrument_mode_string[instrument_mode];

  } else if (instrument_opt_mode == INSTRUMENT_OPT_CTX)

    ptr = alloc_printf("%s + CTX", instrument_mode_string[instrument_mode]);
  else if (instrument_opt_mode == INSTRUMENT_OPT_NGRAM)
    ptr = alloc_printf("%s + NGRAM-%u", instrument_mode_string[instrument_mode],
                       ngram_size);
  else
    ptr = alloc_printf("%s + CTX + NGRAM-%u",
                       instrument_mode_string[instrument_mode], ngram_size);

#ifndef AFL_CLANG_FLTO
  if (lto_mode)
    FATAL(
        "instrumentation mode LTO specified but LLVM support not available "
        "(requires LLVM 11 or higher)");
#endif

  if (instrument_opt_mode && instrument_mode != INSTRUMENT_CLASSIC &&
      instrument_mode != INSTRUMENT_CFG)
    FATAL(
        "CTX and NGRAM instrumentation options can only be used with CFG "
        "(recommended) and CLASSIC instrumentation modes!");

  if (getenv("AFL_LLVM_SKIP_NEVERZERO") && getenv("AFL_LLVM_NOT_ZERO"))
    FATAL(
        "AFL_LLVM_NOT_ZERO and AFL_LLVM_SKIP_NEVERZERO can not be set "
        "together");

  if (instrument_mode == INSTRUMENT_PCGUARD &&
      (getenv("AFL_LLVM_INSTRUMENT_FILE") || getenv("AFL_LLVM_WHITELIST")))
    WARNF(
        "Instrumentation type PCGUARD does not support "
        "AFL_LLVM_INSTRUMENT_FILE!");

  if (argc < 2 || strcmp(argv[1], "-h") == 0) {

    if (!lto_mode)
      printf("afl-clang-fast" VERSION " by <lszekeres@google.com> in %s mode\n",
             ptr);
    else
      printf("afl-clang-lto" VERSION
             "  by Marc \"vanHauser\" Heuse <mh@mh-sec.de> in %s mode\n",
             ptr);

    SAYF(
        "\n"
        "%s[++] [options]\n"
        "\n"
        "This is a helper application for afl-fuzz. It serves as a drop-in "
        "replacement\n"
        "for clang, letting you recompile third-party code with the "
        "required "
        "runtime\n"
        "instrumentation. A common use pattern would be one of the "
        "following:\n\n"

        "  CC=%s/afl-clang-fast ./configure\n"
        "  CXX=%s/afl-clang-fast++ ./configure\n\n"

        "In contrast to the traditional afl-clang tool, this version is "
        "implemented as\n"
        "an LLVM pass and tends to offer improved performance with slow "
        "programs.\n\n"

        "Environment variables used:\n"
        "AFL_CC: path to the C compiler to use\n"
        "AFL_CXX: path to the C++ compiler to use\n"
        "AFL_DEBUG: enable developer debugging output\n"
        "AFL_DONT_OPTIMIZE: disable optimization instead of -O3\n"
        "AFL_HARDEN: adds code hardening to catch memory bugs\n"
        "AFL_INST_RATIO: percentage of branches to instrument\n"
        "AFL_LLVM_NOT_ZERO: use cycling trace counters that skip zero\n"
        "AFL_LLVM_SKIP_NEVERZERO: do not skip zero on trace counters\n"
        "AFL_LLVM_LAF_SPLIT_COMPARES: enable cascaded comparisons\n"
        "AFL_LLVM_LAF_SPLIT_COMPARES_BITW: size limit (default 8)\n"
        "AFL_LLVM_LAF_SPLIT_SWITCHES: casc. comp. in 'switch'\n"
        " to cascaded comparisons\n"
        "AFL_LLVM_LAF_SPLIT_FLOATS: transform floating point comp. to "
        "cascaded comp.\n"
        "AFL_LLVM_LAF_TRANSFORM_COMPARES: transform library comparison "
        "function calls\n"
        "AFL_LLVM_LAF_ALL: enables all LAF splits/transforms\n"
        "AFL_LLVM_INSTRUMENT_FILE: enable the instrument file listing "
        "(selective "
        "instrumentation)\n"
        "AFL_NO_BUILTIN: compile for use with libtokencap.so\n"
        "AFL_PATH: path to instrumenting pass and runtime "
        "(afl-llvm-rt.*o)\n"
        "AFL_QUIET: suppress verbose output\n"
        "AFL_USE_ASAN: activate address sanitizer\n"
        "AFL_USE_CFISAN: activate control flow sanitizer\n"
        "AFL_USE_MSAN: activate memory sanitizer\n"
        "AFL_USE_UBSAN: activate undefined behaviour sanitizer\n",
        callname, BIN_PATH, BIN_PATH);

    SAYF(
        "\nafl-clang-fast specific environment variables:\n"
        "AFL_LLVM_CMPLOG: log operands of comparisons (RedQueen mutator)\n"
        "AFL_LLVM_INSTRUMENT: set instrumentation mode: AFL, CFG "
        "(INSTRIM), PCGUARD [DEFAULT], LTO, CTX, NGRAM-2 ... NGRAM-16\n"
        " You can also use the old environment variables instead:\n"
        "  AFL_LLVM_USE_TRACE_PC: use LLVM trace-pc-guard instrumentation "
        "[DEFAULT]\n"
        "  AFL_LLVM_INSTRIM: use light weight instrumentation InsTrim\n"
        "  AFL_LLVM_INSTRIM_LOOPHEAD: optimize loop tracing for speed ("
        "option to INSTRIM)\n"
        "  AFL_LLVM_CTX: use context sensitive coverage\n"
        "  AFL_LLVM_NGRAM_SIZE: use ngram prev_loc count coverage\n");

#ifdef AFL_CLANG_FLTO
    SAYF(
        "\nafl-clang-lto specific environment variables:\n"
        "AFL_LLVM_LTO_DONTWRITEID: don't write the highest ID used to a "
        "global var\n"
        "AFL_LLVM_LTO_STARTID: from which ID to start counting from for a "
        "bb\n"
        "AFL_REAL_LD: use this lld linker instead of the compiled in path\n"
        "\nafl-clang-lto was built with linker target \"%s\" and LTO flags "
        "\"%s\"\n"
        "If anything fails - be sure to read README.lto.md!\n",
        AFL_REAL_LD, AFL_CLANG_FLTO);
#endif

    SAYF(
        "\nafl-clang-fast was built for llvm %s with the llvm binary path "
        "of \"%s\".\n",
        LLVM_VERSION, LLVM_BINDIR);

    SAYF("\n");

    exit(1);

  } else if ((isatty(2) && !be_quiet) ||

             getenv("AFL_DEBUG") != NULL) {

    if (!lto_mode)

      SAYF(cCYA "afl-clang-fast" VERSION cRST
                " by <lszekeres@google.com> in %s mode\n",
           ptr);

    else

      SAYF(cCYA "afl-clang-lto" VERSION cRST
                " by Marc \"vanHauser\" Heuse <mh@mh-sec.de> in mode %s\n",
           ptr);

  }

  u8 *ptr2;
  if (!be_quiet && !lto_mode &&
      ((ptr2 = getenv("AFL_MAP_SIZE")) || (ptr2 = getenv("AFL_MAPSIZE")))) {

    u32 map_size = atoi(ptr2);
    if (map_size != MAP_SIZE)
      FATAL("AFL_MAP_SIZE is not supported by afl-clang-fast");

  }

  if (debug) {

    SAYF(cMGN "[D]" cRST " cd \"%s\";", getthecwd());
    for (i = 0; i < argc; i++)
      SAYF(" \"%s\"", argv[i]);
    SAYF("\n");

  }

  check_environment_vars(envp);

  if (getenv("AFL_LLVM_LAF_ALL")) {

    setenv("AFL_LLVM_LAF_SPLIT_SWITCHES", "1", 1);
    setenv("AFL_LLVM_LAF_SPLIT_COMPARES", "1", 1);
    setenv("AFL_LLVM_LAF_SPLIT_FLOATS", "1", 1);
    setenv("AFL_LLVM_LAF_TRANSFORM_COMPARES", "1", 1);

  }

  cmplog_mode = getenv("AFL_CMPLOG") || getenv("AFL_LLVM_CMPLOG");
  if (!be_quiet && cmplog_mode)
    printf("CmpLog mode by <andreafioraldi@gmail.com>\n");

#ifndef __ANDROID__
  find_obj(argv[0]);
#endif

  edit_params(argc, argv, envp);

  if (debug) {

    SAYF(cMGN "[D]" cRST " cd \"%s\";", getthecwd());
    for (i = 0; i < cc_par_cnt; i++)
      SAYF(" \"%s\"", cc_params[i]);
    SAYF("\n");

  }

  execvp(cc_params[0], (char **)cc_params);

  FATAL("Oops, failed to execute '%s' - check your PATH", cc_params[0]);

  return 0;

}

