1 // Copyright 2006-2008 the V8 project authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef V8_FLAGS_FLAGS_H_ 6 #define V8_FLAGS_FLAGS_H_ 7 8 #include <vector> 9 10 #include "src/common/globals.h" 11 #include "src/wasm/wasm-limits.h" 12 13 namespace v8 { 14 namespace internal { 15 16 // Declare all of our flags. 17 #define FLAG_MODE_DECLARE 18 #include "src/flags/flag-definitions.h" // NOLINT 19 20 // The global list of all flags. 21 class V8_EXPORT_PRIVATE FlagList { 22 public: 23 // The list of all flags with a value different from the default 24 // and their values. The format of the list is like the format of the 25 // argv array passed to the main function, e.g. 26 // ("--prof", "--log-file", "v8.prof", "--nolazy"). 27 // 28 // The caller is responsible for disposing the list, as well 29 // as every element of it. 30 static std::vector<const char*>* argv(); 31 32 class HelpOptions { 33 public: 34 enum ExitBehavior : bool { kExit = true, kDontExit = false }; 35 36 explicit HelpOptions(ExitBehavior exit_behavior = kExit, 37 const char* usage = nullptr) exit_behavior_(exit_behavior)38 : exit_behavior_(exit_behavior), usage_(usage) {} 39 ShouldExit()40 bool ShouldExit() { return exit_behavior_ == kExit; } HasUsage()41 bool HasUsage() { return usage_ != nullptr; } usage()42 const char* usage() { return usage_; } 43 44 private: 45 ExitBehavior exit_behavior_; 46 const char* usage_; 47 }; 48 49 // Set the flag values by parsing the command line. If remove_flags is 50 // set, the recognized flags and associated values are removed from (argc, 51 // argv) and only unknown arguments remain. Returns 0 if no error occurred. 52 // Otherwise, returns the argv index > 0 for the argument where an error 53 // occurred. In that case, (argc, argv) will remain unchanged independent of 54 // the remove_flags value, and no assumptions about flag settings should be 55 // made. If exit_behavior is set to Exit and --help has been specified on the 56 // command line, then the usage string will be printed, if it was specified, 57 // followed by the help flag and then the process will exit. Otherwise the 58 // flag help will be displayed but execution will continue. 59 // 60 // The following syntax for flags is accepted (both '-' and '--' are ok): 61 // 62 // --flag (bool flags only) 63 // --no-flag (bool flags only) 64 // --flag=value (non-bool flags only, no spaces around '=') 65 // --flag value (non-bool flags only) 66 // -- (capture all remaining args in JavaScript) 67 static int SetFlagsFromCommandLine( 68 int* argc, char** argv, bool remove_flags, 69 FlagList::HelpOptions help_options = FlagList::HelpOptions()); 70 71 // Set the flag values by parsing the string str. Splits string into argc 72 // substrings argv[], each of which consisting of non-white-space chars, 73 // and then calls SetFlagsFromCommandLine() and returns its result. 74 static int SetFlagsFromString(const char* str, size_t len); 75 76 // Reset all flags to their default value. 77 static void ResetAllFlags(); 78 79 // Print help to stdout with flags, types, and default values. 80 static void PrintHelp(); 81 82 // Set flags as consequence of being implied by another flag. 83 static void EnforceFlagImplications(); 84 85 // Hash of flags (to quickly determine mismatching flag expectations). 86 // This hash is calculated during V8::Initialize and cached. 87 static uint32_t Hash(); 88 }; 89 90 } // namespace internal 91 } // namespace v8 92 93 #endif // V8_FLAGS_FLAGS_H_ 94