citadel/dynloader.c

   1 /*******************************************************
   2  *
   3  * Citadel Dynamic Loading Module
   4  * Written by Brian Costello
   5  * btx@calyx.net
   6  *
   7  * $Id$
   8  *
   9  ******************************************************/
  10
  11
  12 #include "sysdep.h"
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <dlfcn.h>
  16 #include <sys/types.h>
  17 #include <dirent.h>
  18 #include <strings.h>
  19 #include <syslog.h>
  20 #ifdef HAVE_PTHREAD_H
  21 #include <pthread.h>
  22 #endif
  23 #include <limits.h>
  24 #include <ctype.h>
  25 #include "dynloader.h"
  26 #include "citadel.h"
  27 #include "server.h"
  28 #include "sysdep_decls.h"
  29 #include "tools.h"
  30
  31 #ifndef HAVE_SNPRINTF
  32 #include <stdarg.h>
  33 #include "snprintf.h"
  34 #endif
  35
  36 struct LogFunctionHook *LogHookTable = NULL;
  37 struct CleanupFunctionHook *CleanupHookTable = NULL;
  38 struct SessionFunctionHook *SessionHookTable = NULL;
  39 struct UserFunctionHook *UserHookTable = NULL;
  40
  41 struct ProtoFunctionHook {
  42         void (*handler) (char *cmdbuf);
  43         char *cmd;
  44         char *desc;
  45         struct ProtoFunctionHook *next;
  46 } *ProtoHookList = NULL;
  47
  48 void CtdlRegisterProtoHook(void (*handler) (char *), char *cmd, char *desc)
  49 {
  50         struct ProtoFunctionHook *p = mallok(sizeof *p);
  51
  52         if (p == NULL) {
  53                 fprintf(stderr, "can't malloc new ProtoFunctionHook\n");
  54                 exit(EXIT_FAILURE);
  55         }
  56         p->handler = handler;
  57         p->cmd = cmd;
  58         p->desc = desc;
  59         p->next = ProtoHookList;
  60         ProtoHookList = p;
  61 }
  62
  63 int DLoader_Exec_Cmd(char *cmdbuf)
  64 {
  65         struct ProtoFunctionHook *p;
  66
  67         for (p = ProtoHookList; p; p = p->next) {
  68                 if (!strncasecmp(cmdbuf, p->cmd, 4)) {
  69                         p->handler(&cmdbuf[5]);
  70                         return 1;
  71                 }
  72         }
  73         return 0;
  74 }
  75
  76 void DLoader_Init(char *pathname)
  77 {
  78         void *fcn_handle;
  79         char dl_error[256];
  80         DIR *dir;
  81         int i;
  82         struct dirent *dptr;
  83         struct DLModule_Info *(*h_init_fcn) (void);
  84         struct DLModule_Info *dl_info;
  85
  86         char pathbuf[PATH_MAX];
  87
  88         if ((dir = opendir(pathname)) == NULL) {
  89                 perror("opendir");
  90                 exit(1);
  91         }
  92         while ((dptr = readdir(dir)) != NULL) {
  93                 if (dptr->d_name[0] == '.')
  94                         continue;
  95                 lprintf(9, "Attempting to load %s\n", dptr->d_name);
  96
  97                 snprintf(pathbuf, PATH_MAX, "%s/%s", pathname, dptr->d_name);
  98 #ifdef RTLD_NOW
  99                 if (!(fcn_handle = dlopen(pathbuf, RTLD_NOW)))
 100 #else                           /* OpenBSD */
 101                 if (!(fcn_handle = dlopen(pathbuf, DL_LAZY)))
 102 #endif
 103                 {
 104                         safestrncpy(dl_error, dlerror(), sizeof dl_error);
 105                         for (i=0; i<strlen(dl_error); ++i)
 106                                 if (!isprint(dl_error[i]))
 107                                         dl_error[i]='.';
 108                         fprintf(stderr, "DLoader_Init dlopen failed: %s\n",
 109                                 dl_error);
 110                         continue;
 111                 }
 112                 h_init_fcn = (struct DLModule_Info * (*)(void))
 113 #ifndef __OpenBSD__
 114                     dlsym(fcn_handle, "Dynamic_Module_Init");
 115 #else
 116                     dlsym(fcn_handle, "_Dynamic_Module_Init");
 117 #endif
 118
 119                 if (dlerror() != NULL) {
 120                         fprintf(stderr, "DLoader_Init dlsym failed\n");
 121                         continue;
 122                 }
 123                 dl_info = h_init_fcn();
 124
 125                 printf("Loaded module: %s v%d.%d\nBy %s (%s)\n", dl_info->module_name,
 126                        dl_info->major_version, dl_info->minor_version,
 127                    dl_info->module_author, dl_info->module_author_email);
 128         }                       /* While */
 129 }
 130
 131
 132
 133 void CtdlRegisterLogHook(void (*fcn_ptr) (char *), int loglevel)
 134 {
 135
 136         struct LogFunctionHook *newfcn;
 137
 138         newfcn = (struct LogFunctionHook *)
 139             mallok(sizeof(struct LogFunctionHook));
 140         newfcn->next = LogHookTable;
 141         newfcn->h_function_pointer = fcn_ptr;
 142         newfcn->loglevel = loglevel;
 143         LogHookTable = newfcn;
 144
 145         lprintf(5, "Registered a new logging function\n");
 146 }
 147
 148
 149 void CtdlRegisterCleanupHook(void (*fcn_ptr) (void))
 150 {
 151
 152         struct CleanupFunctionHook *newfcn;
 153
 154         newfcn = (struct CleanupFunctionHook *)
 155             mallok(sizeof(struct CleanupFunctionHook));
 156         newfcn->next = CleanupHookTable;
 157         newfcn->h_function_pointer = fcn_ptr;
 158         CleanupHookTable = newfcn;
 159
 160         lprintf(5, "Registered a new cleanup function\n");
 161 }
 162
 163
 164 void CtdlRegisterSessionHook(void (*fcn_ptr) (void), int EventType)
 165 {
 166
 167         struct SessionFunctionHook *newfcn;
 168
 169         newfcn = (struct SessionFunctionHook *)
 170             mallok(sizeof(struct SessionFunctionHook));
 171         newfcn->next = SessionHookTable;
 172         newfcn->h_function_pointer = fcn_ptr;
 173         newfcn->eventtype = EventType;
 174         SessionHookTable = newfcn;
 175
 176         lprintf(5, "Registered a new session function (type %d)\n",
 177                 EventType);
 178 }
 179
 180
 181 void CtdlRegisterUserHook(void (*fcn_ptr) (char *, long), int EventType)
 182 {
 183
 184         struct UserFunctionHook *newfcn;
 185
 186         newfcn = (struct UserFunctionHook *)
 187             mallok(sizeof(struct UserFunctionHook));
 188         newfcn->next = UserHookTable;
 189         newfcn->h_function_pointer = fcn_ptr;
 190         newfcn->eventtype = EventType;
 191         UserHookTable = newfcn;
 192
 193         lprintf(5, "Registered a new user function (type %d)\n",
 194                 EventType);
 195 }
 196
 197
 198 void PerformSessionHooks(int EventType)
 199 {
 200         struct SessionFunctionHook *fcn;
 201
 202         for (fcn = SessionHookTable; fcn != NULL; fcn = fcn->next) {
 203                 if (fcn->eventtype == EventType) {
 204                         (*fcn->h_function_pointer) ();
 205                 }
 206         }
 207 }
 208
 209 void PerformLogHooks(int loglevel, char *logmsg)
 210 {
 211         struct LogFunctionHook *fcn;
 212
 213         for (fcn = LogHookTable; fcn != NULL; fcn = fcn->next) {
 214                 if (fcn->loglevel >= loglevel) {
 215                         (*fcn->h_function_pointer) (logmsg);
 216                 }
 217         }
 218 }
 219
 220 void PerformUserHooks(char *username, long usernum, int EventType)
 221 {
 222         struct UserFunctionHook *fcn;
 223
 224         for (fcn = UserHookTable; fcn != NULL; fcn = fcn->next) {
 225                 if (fcn->eventtype == EventType) {
 226                         (*fcn->h_function_pointer) (username, usernum);
 227                 }
 228         }
 229 }