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 "inspircd_config.h"
  20 #include "inspircd_io.h"
  21 #include "globals.h"
  22 #include "dynamic.h"
  23
  24 #ifndef STATIC_LINK
  25 #include <dlfcn.h>
  26 #else
  27 #include "modlist.h"
  28 #endif
  29
  30 #include "inspstring.h"
  31 #include "helperfuncs.h"
  32 #include <unistd.h>
  33 #include <sys/types.h>
  34 #include <stdio.h>
  35
  36 extern ServerConfig* Config;
  37
  38 DLLManager::DLLManager(char *fname)
  39 {
  40 #ifdef STATIC_LINK
  41         this->staticname[0] = '\0';
  42         log(DEBUG,"Loading core-compiled module '%s'",fname);
  43         for (int j = 0; modsyms[j].name; j++)
  44         {
  45                 log(DEBUG,"Check %s",modsyms[j].name);
  46                 if (!strcmp(modsyms[j].name,fname))
  47                 {
  48                         log(DEBUG,"Found %s",fname);
  49                         strlcpy(this->staticname,fname,1020);
  50                         err = 0;
  51                         return;
  52                 }
  53         }
  54         err = "Module is not statically compiled into the ircd";
  55 #else
  56 #ifdef IS_CYGWIN
  57         // Cygwin behaviour is handled slightly differently
  58         // With the advent of dynamic modules. Because Windows
  59         // wont let you overwrite a file which is currently in
  60         // Use, we can safely attempt to load the module from its
  61         // Current location :)
  62
  63         h = dlopen(fname, RTLD_NOW );
  64         err = (char*)dlerror();
  65
  66 #else
  67         // Copy the library to a temp location, this makes recompiles
  68         // a little safer if the ircd is running at the time as the
  69         // shared libraries are mmap()ed and not doing this causes
  70         // segfaults.
  71         FILE* x = fopen(fname,"rb");
  72         char tmpfile_template[255];
  73         char buffer[65536];
  74         snprintf(tmpfile_template, 255, "/tmp/inspircd_file.so.%d.XXXXXXXXXX",getpid());
  75         int fd = mkstemp(tmpfile_template);
  76         while (!feof(x))
  77         {
  78                 int n = fread(buffer, 1, 65535, x);
  79                 if (n)
  80                         write(fd,buffer,n);
  81         }
  82
  83         // Try to open the library now and get any error message.
  84
  85         h = dlopen(tmpfile_template, RTLD_NOW );
  86         err = (char*)dlerror();
  87         close(fd);
  88         // We can delete the tempfile once it's loaded, leaving just the inode.
  89         if (!Config->debugging)
  90                 unlink(tmpfile_template);
  91 #endif
  92 #endif
  93 }
  94
  95 DLLManager::~DLLManager()
  96 {
  97 #ifndef STATIC_LINK
  98         // close the library if it isn't null
  99         if (h != 0)
 100         dlclose(h);
 101 #endif
 102 }
 103
 104
 105
 106 #ifdef STATIC_LINK
 107
 108 bool DLLManager::GetSymbol(initfunc* &v, char *sym_name)
 109 {
 110         log(DEBUG,"Symbol search...");
 111         for (int j = 0; modsyms[j].name; j++)
 112         {
 113                 if (!strcmp(this->staticname,modsyms[j].name))
 114                 {
 115                         log(DEBUG,"Loading symbol...");
 116                         v = modsyms[j].value;
 117                         err = 0;
 118                         return true;
 119                 }
 120         }
 121         err = "Module symbol missing from the core";
 122         return false;
 123 }
 124
 125 #else
 126
 127 bool DLLManager::GetSymbol(void **v, char *sym_name)
 128 {
 129         // try extract a symbol from the library
 130         // get any error message is there is any
 131
 132         if(h != 0)
 133         {
 134                 *v = dlsym( h, sym_name );
 135                 err = (char*)dlerror();
 136                 if( err == 0 )
 137                         return true;
 138                 else
 139                         return false;
 140         }
 141         else
 142         {
 143                 return false;
 144         }
 145 }
 146
 147 #endif
 148
 149 DLLFactoryBase::DLLFactoryBase(char *fname, char *factory) : DLLManager(fname)
 150 {
 151         // try get the factory function if there is no error yet
 152
 153         factory_func = 0;
 154
 155         if(LastError() == 0)
 156         {
 157 #ifdef STATIC_LINK
 158                 GetSymbol( factory_func, factory ? factory : (char*)"init_module" );
 159 #else
 160                 GetSymbol( (void **)&factory_func, factory ? factory : (char*)"init_module" );
 161 #endif
 162         }
 163 }
 164
 165
 166 DLLFactoryBase::~DLLFactoryBase()
 167 {
 168 }