src/dynamic.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd is copyright (C) 2002-2006 ChatSpike-Dev.
   6  *                       E-mail:
   7  *                <brain@chatspike.net>
   8  *                <Craig@chatspike.net>
   9  *
  10  * Written by Craig Edwards, Craig McLure, and others.
  11  * This program is free but copyrighted software; see
  12  *            the file COPYING for details.
  13  *
  14  * ---------------------------------------------------
  15  */
  16
  17 using namespace std;
  18
  19 #include "configreader.h"
  20 #include "dynamic.h"
  21
  22 #ifndef STATIC_LINK
  23 #include <dlfcn.h>
  24 #else
  25 #include "modlist.h"
  26 #endif
  27
  28 #include "inspircd.h"
  29
  30 DLLManager::DLLManager(InspIRCd* ServerInstance, const char *fname)
  31 {
  32         err = NULL;
  33
  34         if (!strstr(fname,".so"))
  35         {
  36                 err = "This doesn't look like a module file to me...";
  37                 return;
  38         }
  39 #ifdef STATIC_LINK
  40         this->staticname[0] = '\0';
  41         ServerInstance->Log(DEBUG,"Loading core-compiled module '%s'",fname);
  42         for (int j = 0; modsyms[j].name; j++)
  43         {
  44                 ServerInstance->Log(DEBUG,"Check %s",modsyms[j].name);
  45                 if (!strcmp(modsyms[j].name,fname))
  46                 {
  47                         ServerInstance->Log(DEBUG,"Found %s",fname);
  48                         strlcpy(this->staticname,fname,1020);
  49                         err = 0;
  50                         return;
  51                 }
  52         }
  53         err = "Module is not statically compiled into the ircd";
  54 #else
  55         // Copy the library to a temp location, this makes recompiles
  56         // a little safer if the ircd is running at the time as the
  57         // shared libraries are mmap()ed and not doing this causes
  58         // segfaults.
  59         FILE* x = fopen(fname,"rb");
  60         if (!x)
  61         {
  62                 err = strerror(errno);
  63                 return;
  64         }
  65         ServerInstance->Log(DEBUG,"Opened module file %s",fname);
  66         char tmpfile_template[255];
  67         char buffer[65536];
  68         snprintf(tmpfile_template, 255, "%s/inspircd_file.so.%d.XXXXXXXXXX",ServerInstance->Config->TempDir,getpid());
  69         int fd = mkstemp(tmpfile_template);
  70         if (fd == -1)
  71         {
  72                 fclose(x);
  73                 err = strerror(errno);
  74                 return;
  75         }
  76         ServerInstance->Log(DEBUG,"Copying %s to %s",fname, tmpfile_template);
  77         while (!feof(x))
  78         {
  79                 int n = fread(buffer, 1, 65535, x);
  80                 if (n)
  81                 {
  82                         int written = write(fd,buffer,n);
  83                         if (written != n)
  84                         {
  85                                 fclose(x);
  86                                 err = strerror(errno);
  87                                 return;
  88                         }
  89                 }
  90         }
  91         ServerInstance->Log(DEBUG,"Copied entire file.");
  92         // Try to open the library now and get any error message.
  93
  94         if (close(fd) == -1)
  95                 err = strerror(errno);
  96         if (fclose(x) == EOF)
  97                 err = strerror(errno);
  98
  99         h = dlopen(fname, RTLD_NOW|RTLD_LOCAL);
 100         if (!h)
 101         {
 102                 ServerInstance->Log(DEBUG,"dlerror occured!");
 103                 err = (char*)dlerror();
 104                 return;
 105         }
 106
 107         ServerInstance->Log(DEBUG,"Finished loading '%s': %0x",tmpfile_template, h);
 108
 109         // We can delete the tempfile once it's loaded, leaving just the inode.
 110         if (!err && !ServerInstance->Config->debugging)
 111         {
 112                 ServerInstance->Log(DEBUG,"Deleteting %s",tmpfile_template);
 113                 if (unlink(tmpfile_template) == -1)
 114                         err = strerror(errno);
 115         }
 116 #endif
 117 }
 118
 119 DLLManager::~DLLManager()
 120 {
 121 #ifndef STATIC_LINK
 122         // close the library if it isn't null
 123         if (h)
 124                 dlclose(h);
 125 #endif
 126 }
 127
 128
 129
 130 #ifdef STATIC_LINK
 131
 132 bool DLLManager::GetSymbol(initfunc* &v, const char *sym_name)
 133 {
 134         for (int j = 0; modsyms[j].name; j++)
 135         {
 136                 if (!strcmp(this->staticname,modsyms[j].name))
 137                 {
 138                         v = modsyms[j].value;
 139                         err = 0;
 140                         return true;
 141                 }
 142         }
 143         err = "Module symbol missing from the core";
 144         return false;
 145 }
 146
 147 #else
 148
 149 bool DLLManager::GetSymbol(void** v, const char* sym_name)
 150 {
 151         // try extract a symbol from the library
 152         // get any error message is there is any
 153
 154         if (h)
 155         {
 156                 dlerror(); // clear value
 157                 *v = dlsym(h, sym_name);
 158                 err = (char*)dlerror();
 159                 if (!*v || err)
 160                         return false;
 161         }
 162
 163         if (err)
 164         {
 165                 return false;
 166         }
 167         else
 168         {
 169                 return true;
 170         }
 171 }
 172
 173 #endif
 174
 175 DLLFactoryBase::DLLFactoryBase(InspIRCd* Instance, const char* fname, const char* symbol) : DLLManager(Instance, fname)
 176 {
 177         // try get the factory function if there is no error yet
 178         factory_func = 0;
 179
 180         if (!LastError())
 181         {
 182 #ifdef STATIC_LINK
 183                 if (!GetSymbol( factory_func, symbol ? symbol : "init_module"))
 184 #else
 185                 if (!GetSymbol( (void **)&factory_func, symbol ? symbol : "init_module"))
 186 #endif
 187                 {
 188                         throw ModuleException("Missing init_module() entrypoint!");
 189                 }
 190         }
 191 }
 192
 193 DLLFactoryBase::~DLLFactoryBase()
 194 {
 195 }
 196