hphp/runtime/ext/vsdebug/stack_trace_command.cpp

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2017-present Facebook, Inc. (http://www.facebook.com)  |
   6    +----------------------------------------------------------------------+
   7    | This source file is subject to version 3.01 of the PHP license,      |
   8    | that is bundled with this package in the file LICENSE, and is        |
   9    | available through the world-wide-web at the following url:           |
  10    | http://www.php.net/license/3_01.txt                                  |
  11    | If you did not receive a copy of the PHP license and are unable to   |
  12    | obtain it through the world-wide-web, please send a note to          |
  13    | license@php.net so we can mail you a copy immediately.               |
  14    +----------------------------------------------------------------------+
  15 */
  16
  17 #include "hphp/runtime/ext/vsdebug/debugger.h"
  18 #include "hphp/runtime/ext/vsdebug/debugger-request-info.h"
  19 #include "hphp/runtime/ext/vsdebug/command.h"
  20 #include "hphp/runtime/base/backtrace.h"
  21 #include "hphp/runtime/base/tv-variant.h"
  22
  23 #include <filesystem>
  24
  25 namespace HPHP {
  26 namespace VSDEBUG {
  27
  28 StackTraceCommand::StackTraceCommand(
  29   Debugger* debugger,
  30   folly::dynamic message
  31 ) : VSCommand(debugger, message) {
  32 }
  33
  34 StackTraceCommand::~StackTraceCommand() {
  35 }
  36
  37 const StaticString s_file("file");
  38 const StaticString s_line("line");
  39 const StaticString s_function("function");
  40
  41 bool StackTraceCommand::executeImpl(
  42   DebuggerSession* session,
  43   folly::dynamic* responseMsg
  44 ) {
  45   // The request thread should not re-enter the debugger while
  46   // processing this command.
  47   DebuggerNoBreakContext noBreak(m_debugger);
  48
  49   const request_id_t requestId = m_debugger->getCurrentThreadId();
  50   const folly::dynamic& message = getMessage();
  51   const folly::dynamic& args = tryGetObject(message, "arguments", s_emptyArgs);
  52
  53   (*responseMsg)["body"] = folly::dynamic::object;
  54
  55   folly::dynamic& stackTrace = (*responseMsg)["body"];
  56   stackTrace["stackFrames"] = folly::dynamic::array();
  57   folly::dynamic& frames = stackTrace["stackFrames"];
  58
  59   if (m_debugger->getRequestInfo()->m_pauseRecurseCount == 0) {
  60     stackTrace["stackFrames"] = frames;
  61     stackTrace["totalFrames"] = 0;
  62     (*responseMsg)["body"] = stackTrace;
  63     return false;
  64   }
  65
  66   int startFrame = tryGetInt(args, "startFrame", 0);
  67   int levels = tryGetInt(args, "levels", INT_MAX);
  68   if (levels == 0) {
  69     // Per protocol: if levels is 0, all frames should be returned.
  70     levels = INT_MAX;
  71   }
  72   int levelsAdded = 0;
  73
  74   // Respond with a stack trace!
  75   auto backtraceArgs = BacktraceArgs()
  76                         .withSelf()
  77                         .setParserFrame(nullptr);
  78
  79   const Array backtrace = createBacktrace(backtraceArgs);
  80   int backtraceSize = backtrace.size();
  81   const ClientPreferences& prefs = m_debugger->getClientPreferences();
  82
  83   for (int depth = 0; depth < backtraceSize - 1; depth++) {
  84     if (depth < startFrame) {
  85       continue;
  86     }
  87
  88     if (levelsAdded >= levels) {
  89       break;
  90     }
  91
  92     auto const parentFrame = backtrace.lookup(depth + 1);
  93     auto const funcName =
  94       tvCastToString(parentFrame.val().parr->get(s_function)).data();
  95     auto const frame = backtrace.lookup(depth);
  96     const auto file = frame.val().parr->get(s_file);
  97     const auto line = frame.val().parr->get(s_line);
  98
  99     frames.push_back(folly::dynamic::object);
 100     folly::dynamic& stackFrame = frames[frames.size() - 1];
 101     stackFrame["id"] = session->generateFrameId(requestId, depth);
 102     stackFrame["name"] = funcName;
 103
 104     int64_t lineNumber = tvCastToInt64(line);
 105     if (!prefs.linesStartAt1) {
 106       lineNumber--;
 107     }
 108
 109     stackFrame["line"] = lineNumber;
 110     stackFrame["column"] = prefs.columnsStartAt1 ? 1 : 0;
 111
 112     std::string fileName = tvCastToString(file).toCppString();
 113     if (!fileName.empty()) {
 114       stackFrame["source"] = folly::dynamic::object;
 115       folly::dynamic& source = stackFrame["source"];
 116       source["name"] = std::filesystem::path{fileName}.stem().native();
 117       source["path"] = fileName;
 118     }
 119
 120     levelsAdded++;
 121   }
 122
 123   if (backtrace.size() == 0) {
 124     // The backtrace will be empty if the request is just starting up and hasn't
 125     // invoked anything yet.
 126     frames.push_back(folly::dynamic::object);
 127     folly::dynamic& stackFrame = frames[frames.size() - 1];
 128     stackFrame["id"] = -1;
 129     stackFrame["name"] = "{request initializing}";
 130     stackFrame["line"] = 0;
 131     stackFrame["column"] = 0;
 132
 133     folly::dynamic source = folly::dynamic::object;
 134     source["name"] = "<unknown>";
 135     source["path"] = "<unknown>";
 136     stackFrame["source"] = source;
 137   }
 138
 139   stackTrace["totalFrames"] = backtraceSize == 0 ? 0 : backtraceSize - 1;
 140
 141   // Completion of this command does not resume the target.
 142   return false;
 143 }
 144
 145 }
 146 }