compiler-rt/test/fuzzer/SimpleCmpTest.cpp

   1 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   2 // See https://llvm.org/LICENSE.txt for license information.
   3 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   4
   5 // Simple test for a fuzzer. The fuzzer must find several narrow ranges.
   6 #include <cstdint>
   7 #include <cstdio>
   8 #include <cstdlib>
   9 #include <cstring>
  10
  11 extern int AllLines[];
  12
  13 bool PrintOnce(int Line) {
  14   if (!AllLines[Line])
  15     fprintf(stderr, "Seen line %d\n", Line);
  16   AllLines[Line] = 1;
  17   return true;
  18 }
  19
  20 extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
  21   if (Size != 21)
  22     return 0;
  23   uint64_t x = 0;
  24   int64_t  y = 0;
  25   int32_t z = 0;
  26   uint8_t a = 0;
  27   memcpy(&x, Data, 8);  // 8
  28   memcpy(&y, Data + 8, 8);  // 16
  29   memcpy(&z, Data + 16, sizeof(z));  // 20
  30   memcpy(&a, Data + 20, sizeof(a));  // 21
  31   const bool k32bit = sizeof(void*) == 4;
  32
  33   if ((k32bit || x > 1234567890) && PrintOnce(__LINE__) &&
  34       (k32bit || x < 1234567895) && PrintOnce(__LINE__) &&
  35       a == 0x42 && PrintOnce(__LINE__) &&
  36       (k32bit || y >= 987654321) && PrintOnce(__LINE__) &&
  37       (k32bit || y <= 987654325) && PrintOnce(__LINE__) &&
  38       z < -10000 && PrintOnce(__LINE__) &&
  39       z >= -10005 && PrintOnce(__LINE__) &&
  40       z != -10003 && PrintOnce(__LINE__) &&
  41       true) {
  42     fprintf(stderr, "BINGO; Found the target: size %zd (%zd, %zd, %d, %d), exiting.\n",
  43             Size, x, y, z, a);
  44     exit(1);
  45   }
  46   return 0;
  47 }
  48
  49 int AllLines[__LINE__ + 1];  // Must be the last line.