source/gldbg.cpp

   1 #include <algorithm>
   2 #include <stdexcept>
   3 #include <cstdlib>
   4 #include <climits>
   5 #include <fcntl.h>
   6 #include <signal.h>
   7 #include <unistd.h>
   8 #include <sys/poll.h>
   9 #include <sys/socket.h>
  10 #include <readline/readline.h>
  11 #include "functions.h"
  12 #include "gldbg.h"
  13 #include "gldecoder.h"
  14 #include "packet.h"
  15 #include "strformat.h"
  16 #include "tool.h"
  17
  18 using namespace std;
  19
  20 GlDbg *GlDbg::instance = 0;
  21
  22 GlDbg::GlDbg(int argc, char **argv):
  23         cmd_interp(*this),
  24         process(vector<string>(argv+1, argv+argc)),
  25         buf_offset(0),
  26         flushing(false),
  27         got_sigchld(false),
  28         stop_reason(0),
  29         current_break(0)
  30 {
  31         instance = this;
  32
  33         char buf[PATH_MAX];
  34         unsigned len = readlink("/proc/self/exe", buf, sizeof(buf));
  35         string exe(buf, len);
  36         string::size_type slash = exe.rfind('/');
  37         process.setenv("LD_PRELOAD", (exe.substr(0, slash+1)+"glwrap.so"));
  38
  39         const list<Tool::Factory *> &factories = Tool::get_factories();
  40         for(list<Tool::Factory *>::const_iterator i=factories.begin(); i!=factories.end(); ++i)
  41                 tools.push_back((*i)->create(*this));
  42 }
  43
  44 GlDbg::~GlDbg()
  45 {
  46         for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
  47                 delete *i;
  48 }
  49
  50 int GlDbg::main()
  51 {
  52         signal(SIGINT, &sighandler);
  53         signal(SIGCHLD, &sighandler);
  54
  55         printf("GLdbg 0.0\n");
  56         printf("Copyright © 2009-2010 Mikkosoft Productions\n");
  57         printf("Type \"help\" for a list of commands\n");
  58
  59         while(1)
  60                 tick();
  61
  62         return 0;
  63 }
  64
  65 void GlDbg::launch()
  66 {
  67         if(process.get_state()!=Process::INACTIVE)
  68                 throw runtime_error("Program is already running");
  69
  70         int fds[2];
  71         socketpair(AF_UNIX, SOCK_STREAM, 0, fds);
  72         sock_fd = fds[0];
  73
  74         int flags = fcntl(sock_fd, F_GETFD);
  75         fcntl(sock_fd, F_SETFD, flags|FD_CLOEXEC);
  76
  77         process.setenv("GLWRAP_FD", strformat("%d", fds[1]));
  78         process.setenv("GLWRAP_CTRL_FD", strformat("%d", fds[1]));
  79         process.launch();
  80         close(fds[1]);
  81
  82         for(BreakList::iterator i=breakpoints.begin(); i!=breakpoints.end(); )
  83         {
  84                 if(i->has_owner(0))
  85                 {
  86                         i->owners.clear();
  87                         i->owners.push_back(0);
  88                         send_breakpoint(i->function, i->flag, 0);
  89                         ++i;
  90                 }
  91                 else
  92                         breakpoints.erase(i++);
  93         }
  94
  95         for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
  96                 (*i)->process_started();
  97 }
  98
  99 void GlDbg::send(GlPacket *pkt)
 100 {
 101         if(process.get_state()==Process::INACTIVE)
 102                 throw runtime_error("Program is not running");
 103
 104         packet_send(pkt, sock_fd);
 105 }
 106
 107 void GlDbg::hold()
 108 {
 109         GlPacket *pkt = packet_begin(FUNC_GLDHOLD);
 110         send(pkt);
 111 }
 112
 113 void GlDbg::send_breakpoint(unsigned short func, unsigned char set_flags, unsigned char clear_flags)
 114 {
 115         GlPacket *pkt = packet_begin(FUNC_GLDBREAK);
 116         packet_write_short(pkt, func);
 117         packet_write_char(pkt, set_flags);
 118         packet_write_char(pkt, clear_flags);
 119         send(pkt);
 120 }
 121
 122 void GlDbg::set_breakpoint(unsigned short func, unsigned char flag, Tool *owner)
 123 {
 124         Breakpoint *bp = (func ? get_breakpoint(func, flag) : 0);
 125         if(bp)
 126                 bp->add_owner(owner);
 127         else
 128         {
 129                 if(func)
 130                 {
 131                         breakpoints.push_back(Breakpoint(func, flag));
 132                         breakpoints.back().add_owner(owner);
 133                 }
 134
 135                 if(process.get_state()>=Process::RUNNING)
 136                         send_breakpoint(func, flag, 0);
 137         }
 138 }
 139
 140 void GlDbg::clear_breakpoint(unsigned short func, unsigned char flag, Tool *owner)
 141 {
 142         Breakpoint *bp = get_breakpoint(func, flag);
 143         if(bp)
 144         {
 145                 bp->remove_owner(owner);
 146                 if(bp->owners.empty())
 147                 {
 148                         if(current_break==bp)
 149                                 current_break = 0;
 150
 151                         // XXX Inefficient.  Should get_breakpoint() return an iterator?
 152                         for(BreakList::iterator i=breakpoints.begin(); i!=breakpoints.end(); ++i)
 153                                 if(i->function==func && i->flag==flag)
 154                                 {
 155                                         breakpoints.erase(i);
 156                                         break;
 157                                 }
 158
 159                         if(process.get_state()>=Process::RUNNING)
 160                                 send_breakpoint(func, 0, flag);
 161                 }
 162         }
 163 }
 164
 165 void GlDbg::resume_from_break(Tool *tool)
 166 {
 167         if(!current_break)
 168                 return;
 169
 170         ToolList::iterator i = find(break_holders.begin(), break_holders.end(), tool);
 171         if(i!=break_holders.end())
 172                 break_holders.erase(i);
 173
 174         if(break_holders.empty())
 175                 process.resume();
 176 }
 177
 178 void GlDbg::quit(bool force)
 179 {
 180         if(!force && process.get_state()!=Process::INACTIVE)
 181                 throw runtime_error("Program is still running");
 182         exit(0);
 183 }
 184
 185 void GlDbg::tick()
 186 {
 187         if(got_sigchld)
 188         {
 189                 got_sigchld = false;
 190                 stop_reason = process.check();
 191                 if((stop_reason>>8)==3)
 192                         flushing = true;
 193         }
 194
 195         Process::State pstate = process.get_state();
 196         if((pstate!=Process::INACTIVE && pstate!=Process::STOPPED) || flushing)
 197                 read_stream();
 198         else
 199         {
 200                 if(stop_reason)
 201                 {
 202                         if(stop_reason==0x100)
 203                                 printf("Target process exited normally\n");
 204                         else if((stop_reason>>8)==1)
 205                                 printf("Target process exited with status %d\n", stop_reason&0xFF);
 206                         else if((stop_reason>>8)==2)
 207                                 printf("Target process terminated with signal %d\n", stop_reason&0xFF);
 208                         else if((stop_reason>>8)==3)
 209                                 printf("Target process stopped by signal %d\n", stop_reason&0xFF);
 210
 211                         stop_reason = 0;
 212                 }
 213
 214                 char *line = readline("gldbg> ");
 215                 if(line)
 216                 {
 217                         try
 218                         {
 219                                 cmd_interp.execute(line);
 220                         }
 221                         catch(const exception &e)
 222                         {
 223                                 printf("%s\n", e.what());
 224                         }
 225                         free(line);
 226                 }
 227                 else if(pstate==Process::INACTIVE)
 228                         exit(0);
 229         }
 230 }
 231
 232 void GlDbg::read_stream()
 233 {
 234         pollfd pfd = { sock_fd, POLLIN, 0 };
 235         int ret = poll(&pfd, 1, (flushing ? 0 : -1));
 236         if(ret>0)
 237         {
 238                 char rbuf[1024];
 239                 ret = read(sock_fd, rbuf, 1024);
 240                 if(ret>0)
 241                 {
 242                         buffer.append(rbuf, ret);
 243                         while(buffer.size()>buf_offset)
 244                         {
 245                                 const char *data = buffer.data()+buf_offset;
 246                                 unsigned len = buffer.size()-buf_offset;
 247                                 GlPacket *pkt = packet_receive_str(data, &len);
 248                                 if(!pkt)
 249                                         break;
 250
 251                                 unsigned short func;
 252                                 packet_read_short(pkt, (short *)&func);
 253                                 if(func==FUNC_GLDBREAK)
 254                                 {
 255                                         packet_read_short(pkt, (short *)&func);
 256                                         unsigned char flag;
 257                                         packet_read_char(pkt, (char *)&flag);
 258
 259                                         current_break = get_breakpoint(func, flag);
 260                                         bool announce = !current_break;
 261                                         if(current_break)
 262                                         {
 263                                                 break_holders = current_break->owners;
 264                                                 announce = current_break->has_owner(0);
 265                                         }
 266
 267                                         if(announce)
 268                                                 printf("Breakpoint: %s\n", get_function_name(func));
 269                                 }
 270
 271                                 for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
 272                                         (*i)->decode(data, len);
 273                                 buf_offset += len;
 274                         }
 275                         if(buf_offset>8192)
 276                         {
 277                                 buffer.erase(0, buf_offset);
 278                                 buf_offset = 0;
 279                         }
 280                 }
 281         }
 282         else if(flushing)
 283         {
 284                 flushing = false;
 285
 286                 if(stop_reason)
 287                 {
 288                         for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
 289                                 (*i)->process_stopped(stop_reason);
 290
 291                         if(process.get_state()==Process::RUNNING)
 292                                 current_break = 0;
 293                 }
 294         }
 295 }
 296
 297 GlDbg::Breakpoint *GlDbg::get_breakpoint(unsigned short func, unsigned char flag)
 298 {
 299         for(BreakList::iterator i=breakpoints.begin(); i!=breakpoints.end(); ++i)
 300                 if(i->function==func && i->flag==flag)
 301                         return &*i;
 302
 303         return 0;
 304 }
 305
 306 void GlDbg::sighandler(int sig)
 307 {
 308         if(sig==SIGCHLD)
 309                 instance->got_sigchld = true;
 310 }
 311
 312
 313 GlDbg::Breakpoint::Breakpoint(unsigned short f, unsigned char l):
 314         function(f),
 315         flag(l)
 316 { }
 317
 318 void GlDbg::Breakpoint::add_owner(Tool *t)
 319 {
 320         ToolList::iterator i = find(owners.begin(), owners.end(), t);
 321         if(i==owners.end())
 322                 owners.push_back(t);
 323 }
 324
 325 bool GlDbg::Breakpoint::has_owner(Tool *t) const
 326 {
 327         ToolList::const_iterator i = find(owners.begin(), owners.end(), t);
 328         return i!=owners.end();
 329 }
 330
 331 void GlDbg::Breakpoint::remove_owner(Tool *t)
 332 {
 333         ToolList::iterator i = find(owners.begin(), owners.end(), t);
 334         if(i!=owners.end())
 335                 owners.erase(i);
 336 }