tests

src/ast/codegen_llvm.cpp

@@ -461,7 +461,7 @@ void CodegenLLVM::visit(Call &call)
     AllocaInst *system_args = b_.CreateAllocaBPF(printf_struct, "system_args");
     b_.CreateMemSet(system_args, b_.getInt8(0), struct_size, 1);
 
-    b_.CreateStore(b_.getInt64(system_id_ + 10000), system_args);
+    b_.CreateStore(b_.getInt64(system_id_ + asyncactionint(AsyncAction::syscall)), system_args);
     for (int i=1; i<call.vargs->size(); i++)
     {
       Expression &arg = *call.vargs->at(i);
@@ -471,7 +471,6 @@ void CodegenLLVM::visit(Call &call)
         b_.CreateMemCpy(offset, expr_, arg.type.size, 1);
       else
         b_.CreateStore(expr_, offset);
-        // b_.CreateStore(b_.getInt64(asyncactionint(AsyncAction::exit)), perfdata);
     }
 
     system_id_++;

src/bpftrace.cpp

@@ -213,38 +213,39 @@ void perf_event_printer(void *cb_cookie, void *data, int size)
     auto args = std::get<1>(bpftrace->system_args_[id]);
     std::vector<uint64_t> arg_values = bpftrace->get_arg_values(args, arg_data);
 
-    std::string command = "";
+    char buffer [255];
+
     switch (args.size())
     {
       case 0:
         system(fmt);
         break;
       case 1:
-        command = bpftrace->format_string(fmt, arg_values.at(0));
-        system(command.c_str());
+        sprintf(buffer, fmt, arg_values.at(0));
+        system(buffer);
         break;
       case 2:
-        command = bpftrace->format_string(fmt, arg_values.at(0), arg_values.at(1));
-        system(command.c_str());
+        sprintf(buffer, fmt, arg_values.at(0), arg_values.at(1));
+        system(buffer);
         break;
       case 3:
-        command = bpftrace->format_string(fmt, arg_values.at(0), arg_values.at(1), arg_values.at(2));
-        system(command.c_str());
+        sprintf(buffer, fmt, arg_values.at(0), arg_values.at(1), arg_values.at(2));
+        system(buffer);
         break;
       case 4:
-        command = bpftrace->format_string(fmt, arg_values.at(0), arg_values.at(1), arg_values.at(2),
+        sprintf(buffer, fmt, arg_values.at(0), arg_values.at(1), arg_values.at(2),
           arg_values.at(3));
-        system(command.c_str());
+        system(buffer);
         break;
       case 5:
-        command = bpftrace->format_string(fmt, arg_values.at(0), arg_values.at(1), arg_values.at(2),
+        sprintf(buffer, fmt, arg_values.at(0), arg_values.at(1), arg_values.at(2),
           arg_values.at(3), arg_values.at(4));
-        system(command.c_str());
+        system(buffer);
         break;
      case 6:
-        command = bpftrace->format_string(fmt, arg_values.at(0), arg_values.at(1), arg_values.at(2),
+        sprintf(buffer, fmt, arg_values.at(0), arg_values.at(1), arg_values.at(2),
           arg_values.at(3), arg_values.at(4), arg_values.at(5));
-        system(command.c_str());
+        system(buffer);
         break;
       default:
         abort();
@@ -289,47 +290,6 @@ void perf_event_printer(void *cb_cookie, void *data, int size)
   }
 }
 
-void BPFtrace::format_impl(std::stringstream &ss, const char *format)
-{
-  while (*format)
-  {
-    if (*format == '%' && *++format != '%') // %% == % (not a format directive)
-      throw std::invalid_argument("not enough arguments !\n");
-    ss << *format++;
-  }
-}
-
-template <typename Arg, typename... Args>
-void BPFtrace::format_impl(std::stringstream &ss, const char *format, Arg arg, Args... args)
-{
-  while (*format)
-  {
-    if (*format == '%' && *++format != '%')
-    {
-      auto current_format_qualifier = *format;
-      switch (current_format_qualifier)
-      {
-      case 'd':
-        if (!std::is_integral<Arg>())
-          throw std::invalid_argument("%d introduces integral argument");
-      }
-
-      ss << arg;                                 // arg type is deduced
-      return format_impl(ss, ++format, args...); // one arg less
-    }
-    ss << *format++;
-  } // the format string is exhausted and we still have args : throw
-  throw std::invalid_argument("Too many arguments\n");
-}
-
-template <typename... Args>
-std::string BPFtrace::format_string(const char *fmt, Args... args)
-{
-  std::stringstream ss;
-  format_impl(ss, fmt, args...);
-  return ss.str();
-}
-
 std::vector<uint64_t> BPFtrace::get_arg_values(std::vector<Field> args, uint8_t* arg_data)
 {
   std::vector<uint64_t> arg_values;

src/bpftrace.h

@@ -43,16 +43,6 @@ public:
   std::string resolve_name(uint64_t name_id);
   std::vector<uint64_t> get_arg_values(std::vector<Field> args, uint8_t* arg_data);
   void format_impl(std::stringstream& ss, const char* format);
-
-  template <typename Arg, typename... Args>
-  void format_impl(std::stringstream& ss, const char* format, Arg arg, Args... args);
-
-  template <typename... Args>
-  std::string format(const char* fmt, Args... args);
-
-  template <typename... Args>
-  std::string format_string(const char* fmt, Args... args);
-
   int pid_;
 
   std::map<std::string, std::unique_ptr<IMap>> maps_;

tests/codegen.cpp

@@ -1702,6 +1702,41 @@ attributes #1 = { argmemonly nounwind }
 )EXPECTED");
 }
 
+TEST(codegen, call_system)
+{
+  test(" kprobe:f { system(\"echo %d\", 100) }",
+
+R"EXPECTED(%system_t = type { i64, i64 }
+
+; Function Attrs: nounwind
+declare i64 @llvm.bpf.pseudo(i64, i64) #0
+
+; Function Attrs: argmemonly nounwind
+declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture) #1
+
+define i64 @"kprobe:f"(i8*) local_unnamed_addr section "s_kprobe:f" {
+entry:
+  %system_args = alloca %system_t, align 8
+  %1 = bitcast %system_t* %system_args to i8*
+  call void @llvm.lifetime.start.p0i8(i64 -1, i8* nonnull %1)
+  store i64 10000, %system_t* %system_args, align 8
+  %2 = getelementptr inbounds %system_t, %system_t* %system_args, i64 0, i32 1
+  store i64 100, i64* %2, align 8
+  %pseudo = tail call i64 @llvm.bpf.pseudo(i64 1, i64 1)
+  %get_cpu_id = tail call i64 inttoptr (i64 8 to i64 ()*)()
+  %perf_event_output = call i64 inttoptr (i64 25 to i64 (i8*, i8*, i64, i8*, i64)*)(i8* %0, i64 %pseudo, i64 %get_cpu_id, %system_t* nonnull %system_args, i64 16)
+  call void @llvm.lifetime.end.p0i8(i64 -1, i8* nonnull %1)
+  ret i64 0
+}
+
+; Function Attrs: argmemonly nounwind
+declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture) #1
+
+attributes #0 = { nounwind }
+attributes #1 = { argmemonly nounwind }
+)EXPECTED");
+}
+
 TEST(codegen, call_exit)
 {
   test("kprobe:f { exit() }",
@@ -1717,7 +1752,7 @@ entry:
   %perfdata = alloca [8 x i8], align 8
   %1 = getelementptr inbounds [8 x i8], [8 x i8]* %perfdata, i64 0, i64 0
   call void @llvm.lifetime.start.p0i8(i64 -1, i8* nonnull %1)
-  store i64 10000, [8 x i8]* %perfdata, align 8
+  store i64 20000, [8 x i8]* %perfdata, align 8
   %pseudo = tail call i64 @llvm.bpf.pseudo(i64 1, i64 1)
   %get_cpu_id = tail call i64 inttoptr (i64 8 to i64 ()*)()
   %perf_event_output = call i64 inttoptr (i64 25 to i64 (i8*, i8*, i64, i8*, i64)*)(i8* %0, i64 %pseudo, i64 %get_cpu_id, [8 x i8]* nonnull %perfdata, i64 8)
@@ -1768,7 +1803,7 @@ entry:
   %perfdata = alloca [27 x i8], align 8
   %1 = getelementptr inbounds [27 x i8], [27 x i8]* %perfdata, i64 0, i64 0
   call void @llvm.lifetime.start.p0i8(i64 -1, i8* nonnull %1)
-  store i64 10001, [27 x i8]* %perfdata, align 8
+  store i64 20001, [27 x i8]* %perfdata, align 8
   %2 = getelementptr inbounds [27 x i8], [27 x i8]* %perfdata, i64 0, i64 8
   %str.sroa.0.0..sroa_idx = getelementptr inbounds [27 x i8], [27 x i8]* %perfdata, i64 0, i64 24
   call void @llvm.memset.p0i8.i64(i8* nonnull %2, i8 0, i64 16, i32 8, i1 false)
@@ -1827,7 +1862,7 @@ entry:
   %perfdata = alloca [11 x i8], align 8
   %1 = getelementptr inbounds [11 x i8], [11 x i8]* %perfdata, i64 0, i64 0
   call void @llvm.lifetime.start.p0i8(i64 -1, i8* nonnull %1)
-  store i64 10002, [11 x i8]* %perfdata, align 8
+  store i64 20002, [11 x i8]* %perfdata, align 8
   %str.sroa.0.0..sroa_idx = getelementptr inbounds [11 x i8], [11 x i8]* %perfdata, i64 0, i64 8
   store i8 64, i8* %str.sroa.0.0..sroa_idx, align 8
   %str.sroa.4.0..sroa_idx = getelementptr inbounds [11 x i8], [11 x i8]* %perfdata, i64 0, i64 9
@@ -1881,7 +1916,7 @@ entry:
   %perfdata = alloca [11 x i8], align 8
   %1 = getelementptr inbounds [11 x i8], [11 x i8]* %perfdata, i64 0, i64 0
   call void @llvm.lifetime.start.p0i8(i64 -1, i8* nonnull %1)
-  store i64 10003, [11 x i8]* %perfdata, align 8
+  store i64 20003, [11 x i8]* %perfdata, align 8
   %str.sroa.0.0..sroa_idx = getelementptr inbounds [11 x i8], [11 x i8]* %perfdata, i64 0, i64 8
   store i8 64, i8* %str.sroa.0.0..sroa_idx, align 8
   %str.sroa.4.0..sroa_idx = getelementptr inbounds [11 x i8], [11 x i8]* %perfdata, i64 0, i64 9
@@ -1915,7 +1950,7 @@ entry:
   %perfdata = alloca [16 x i8], align 8
   %1 = getelementptr inbounds [16 x i8], [16 x i8]* %perfdata, i64 0, i64 0
   call void @llvm.lifetime.start.p0i8(i64 -1, i8* nonnull %1)
-  store i64 10004, [16 x i8]* %perfdata, align 8
+  store i64 20004, [16 x i8]* %perfdata, align 8
   %2 = getelementptr inbounds [16 x i8], [16 x i8]* %perfdata, i64 0, i64 8
   store i64 0, i8* %2, align 8
   %pseudo = tail call i64 @llvm.bpf.pseudo(i64 1, i64 1)

tests/semantic_analyser.cpp

@@ -88,6 +88,7 @@ TEST(semantic_analyser, builtin_functions)
   test("kprobe:f { exit() }", 0);
   test("kprobe:f { str(0xffff) }", 0);
   test("kprobe:f { printf(\"hello\\n\") }", 0);
+  test("kprobe:f { system(\"ls\\n\") }", 0);
   test("kprobe:f { join(0) }", 0);
   test("kprobe:f { sym(0xffff) }", 0);
   test("kprobe:f { usym(0xffff) }", 0);
@@ -370,6 +371,14 @@ TEST(semantic_analyser, printf)
   test("kprobe:f { $x = printf(\"hi\") }", 1);
 }
 
+TEST(semantic_analyser, system)
+{
+  test("kprobe:f { system(\"ls\") }", 0);
+  test("kprobe:f { system(1234) }", 1);
+  test("kprobe:f { system() }", 1);
+  test("kprobe:f { $fmt = \"mystring\"; system($fmt) }", 1);
+}
+
 TEST(semantic_analyser, printf_format_int)
 {
   test("kprobe:f { printf(\"int: %d\", 1234) }", 0);