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         breakpoints.clear();
  83         for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
  84                 (*i)->process_started();
  85 }
  86
  87 void GlDbg::send(GlPacket *pkt)
  88 {
  89         packet_send(pkt, sock_fd);
  90 }
  91
  92 void GlDbg::hold()
  93 {
  94         GlPacket *pkt = packet_begin(FUNC_GLDHOLD);
  95         send(pkt);
  96 }
  97
  98 void GlDbg::set_breakpoint(unsigned short func, unsigned char flag, Tool *owner)
  99 {
 100         Breakpoint *bp = (func ? get_breakpoint(func, flag) : 0);
 101         if(bp)
 102                 bp->add_owner(owner);
 103         else
 104         {
 105                 if(func)
 106                 {
 107                         breakpoints.push_back(Breakpoint(func, flag));
 108                         breakpoints.back().add_owner(owner);
 109                 }
 110
 111                 GlPacket *pkt = packet_begin(FUNC_GLDBREAK);
 112                 packet_write_short(pkt, func);
 113                 packet_write_char(pkt, flag);
 114                 packet_write_char(pkt, 0);
 115                 send(pkt);
 116         }
 117 }
 118
 119 void GlDbg::clear_breakpoint(unsigned short func, unsigned char flag, Tool *owner)
 120 {
 121         Breakpoint *bp = get_breakpoint(func, flag);
 122         if(bp)
 123         {
 124                 bp->remove_owner(owner);
 125                 if(bp->owners.empty())
 126                 {
 127                         if(current_break==bp)
 128                                 current_break = 0;
 129
 130                         // XXX Inefficient.  Should get_breakpoint() return an iterator?
 131                         for(BreakList::iterator i=breakpoints.begin(); i!=breakpoints.end(); ++i)
 132                                 if(i->function==func && i->flag==flag)
 133                                 {
 134                                         breakpoints.erase(i);
 135                                         break;
 136                                 }
 137
 138                         GlPacket *pkt = packet_begin(FUNC_GLDBREAK);
 139                         packet_write_short(pkt, func);
 140                         packet_write_char(pkt, 0);
 141                         packet_write_char(pkt, flag);
 142                         send(pkt);
 143                 }
 144         }
 145 }
 146
 147 void GlDbg::resume_from_break(Tool *tool)
 148 {
 149         if(!current_break)
 150                 return;
 151
 152         ToolList::iterator i = find(break_holders.begin(), break_holders.end(), tool);
 153         if(i!=break_holders.end())
 154                 break_holders.erase(i);
 155
 156         if(break_holders.empty())
 157                 process.resume();
 158 }
 159
 160 void GlDbg::quit(bool force)
 161 {
 162         if(!force && process.get_state()!=Process::INACTIVE)
 163                 throw runtime_error("Program is still running");
 164         exit(0);
 165 }
 166
 167 void GlDbg::tick()
 168 {
 169         if(got_sigchld)
 170         {
 171                 got_sigchld = false;
 172                 stop_reason = process.check();
 173                 if((stop_reason>>8)==3)
 174                         flushing = true;
 175         }
 176
 177         Process::State pstate = process.get_state();
 178         if((pstate!=Process::INACTIVE && pstate!=Process::STOPPED) || flushing)
 179                 read_stream();
 180         else
 181         {
 182                 if(stop_reason)
 183                 {
 184                         if(stop_reason==0x100)
 185                                 printf("Target process exited normally\n");
 186                         else if((stop_reason>>8)==1)
 187                                 printf("Target process exited with status %d\n", stop_reason&0xFF);
 188                         else if((stop_reason>>8)==2)
 189                                 printf("Target process terminated with signal %d\n", stop_reason&0xFF);
 190                         else if((stop_reason>>8)==3)
 191                                 printf("Target process stopped by signal %d\n", stop_reason&0xFF);
 192
 193                         stop_reason = 0;
 194                 }
 195
 196                 char *line = readline("gldbg> ");
 197                 if(line)
 198                 {
 199                         try
 200                         {
 201                                 cmd_interp.execute(line);
 202                         }
 203                         catch(const exception &e)
 204                         {
 205                                 printf("%s\n", e.what());
 206                         }
 207                         free(line);
 208                 }
 209                 else if(pstate==Process::INACTIVE)
 210                         exit(0);
 211         }
 212 }
 213
 214 void GlDbg::read_stream()
 215 {
 216         pollfd pfd = { sock_fd, POLLIN, 0 };
 217         int ret = poll(&pfd, 1, (flushing ? 0 : -1));
 218         if(ret>0)
 219         {
 220                 char rbuf[1024];
 221                 ret = read(sock_fd, rbuf, 1024);
 222                 if(ret>0)
 223                 {
 224                         buffer.append(rbuf, ret);
 225                         while(buffer.size()>buf_offset)
 226                         {
 227                                 const char *data = buffer.data()+buf_offset;
 228                                 unsigned len = buffer.size()-buf_offset;
 229                                 GlPacket *pkt = packet_receive_str(data, &len);
 230                                 if(!pkt)
 231                                         break;
 232
 233                                 unsigned short func;
 234                                 packet_read_short(pkt, (short *)&func);
 235                                 if(func==FUNC_GLDBREAK)
 236                                 {
 237                                         packet_read_short(pkt, (short *)&func);
 238                                         unsigned char flag;
 239                                         packet_read_char(pkt, (char *)&flag);
 240
 241                                         current_break = get_breakpoint(func, flag);
 242                                         bool announce = !current_break;
 243                                         if(current_break)
 244                                         {
 245                                                 break_holders = current_break->owners;
 246                                                 announce = current_break->has_owner(0);
 247                                         }
 248
 249                                         if(announce)
 250                                                 printf("Breakpoint: %s\n", get_function_name(func));
 251                                 }
 252
 253                                 for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
 254                                         (*i)->decode(data, len);
 255                                 buf_offset += len;
 256                         }
 257                         if(buf_offset>8192)
 258                         {
 259                                 buffer.erase(0, buf_offset);
 260                                 buf_offset = 0;
 261                         }
 262                 }
 263         }
 264         else if(flushing)
 265         {
 266                 flushing = false;
 267
 268                 if(stop_reason)
 269                 {
 270                         for(ToolList::iterator i=tools.begin(); i!=tools.end(); ++i)
 271                                 (*i)->process_stopped(stop_reason);
 272
 273                         if(process.get_state()==Process::RUNNING)
 274                                 current_break = 0;
 275                 }
 276         }
 277 }
 278
 279 GlDbg::Breakpoint *GlDbg::get_breakpoint(unsigned short func, unsigned char flag)
 280 {
 281         for(BreakList::iterator i=breakpoints.begin(); i!=breakpoints.end(); ++i)
 282                 if(i->function==func && i->flag==flag)
 283                         return &*i;
 284
 285         return 0;
 286 }
 287
 288 void GlDbg::sighandler(int sig)
 289 {
 290         if(sig==SIGCHLD)
 291                 instance->got_sigchld = true;
 292 }
 293
 294
 295 GlDbg::Breakpoint::Breakpoint(unsigned short f, unsigned char l):
 296         function(f),
 297         flag(l)
 298 { }
 299
 300 void GlDbg::Breakpoint::add_owner(Tool *t)
 301 {
 302         ToolList::iterator i = find(owners.begin(), owners.end(), t);
 303         if(i==owners.end())
 304                 owners.push_back(t);
 305 }
 306
 307 bool GlDbg::Breakpoint::has_owner(Tool *t) const
 308 {
 309         ToolList::const_iterator i = find(owners.begin(), owners.end(), t);
 310         return i!=owners.end();
 311 }
 312
 313 void GlDbg::Breakpoint::remove_owner(Tool *t)
 314 {
 315         ToolList::iterator i = find(owners.begin(), owners.end(), t);
 316         if(i!=owners.end())
 317                 owners.erase(i);
 318 }