/* MikMod sound library (c) 1998, 1999, 2000, 2001 Miodrag Vallat and others - see file AUTHORS for complete list. This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /*============================================================================== $Id: mdriver.c,v 1.4 2007/12/03 20:59:05 denis111 Exp $ These routines are used to access the available soundcard drivers. ==============================================================================*/ #ifdef HAVE_CONFIG_H #include "config.h" #endif #ifdef HAVE_UNISTD_H #include #endif #if 0 #if defined unix || (defined __APPLE__ && defined __MACH__) #include #include #endif #endif #include #ifdef HAVE_STRINGS_H #include #endif #include "mikmod_internals.h" #ifdef SUNOS extern int fprintf(FILE *, const char *, ...); #endif static MDRIVER *firstdriver=NULL; MIKMODAPI MDRIVER *md_driver=NULL; extern MODULE *pf; /* modfile being played */ /* Initial global settings */ MIKMODAPI UWORD md_device = 0; /* autodetect */ MIKMODAPI UWORD md_mixfreq = 44100; MIKMODAPI UWORD md_mode = DMODE_STEREO | DMODE_16BITS | DMODE_SURROUND |DMODE_SOFT_MUSIC | DMODE_SOFT_SNDFX; MIKMODAPI UBYTE md_pansep = 128; /* 128 == 100% (full left/right) */ MIKMODAPI UBYTE md_reverb = 0; /* no reverb */ MIKMODAPI UBYTE md_volume = 128; /* global sound volume (0-128) */ MIKMODAPI UBYTE md_musicvolume = 128; /* volume of song */ MIKMODAPI UBYTE md_sndfxvolume = 128; /* volume of sound effects */ UWORD md_bpm = 125; /* tempo */ /* Do not modify the numchn variables yourself! use MD_SetVoices() */ UBYTE md_numchn=0,md_sngchn=0,md_sfxchn=0; UBYTE md_hardchn=0,md_softchn=0; void (*md_player)(void) = Player_HandleTick; static volatile int isplaying=0, initialized = 0; static UBYTE *sfxinfo; static int sfxpool; static SAMPLE **md_sample = NULL; /* Previous driver in use */ static SWORD olddevice = -1; /* Limits the number of hardware voices to the specified amount. This function should only be used by the low-level drivers. */ static void LimitHardVoices(int limit) { int t=0; if (!(md_mode & DMODE_SOFT_SNDFX) && (md_sfxchn>limit)) md_sfxchn=limit; if (!(md_mode & DMODE_SOFT_MUSIC) && (md_sngchn>limit)) md_sngchn=limit; if (!(md_mode & DMODE_SOFT_SNDFX)) md_hardchn=md_sfxchn; else md_hardchn=0; if (!(md_mode & DMODE_SOFT_MUSIC)) md_hardchn += md_sngchn; while (md_hardchn>limit) { if (++t & 1) { if (!(md_mode & DMODE_SOFT_SNDFX) && (md_sfxchn>4)) md_sfxchn--; } else { if (!(md_mode & DMODE_SOFT_MUSIC) && (md_sngchn>8)) md_sngchn--; } if (!(md_mode & DMODE_SOFT_SNDFX)) md_hardchn=md_sfxchn; else md_hardchn=0; if (!(md_mode & DMODE_SOFT_MUSIC)) md_hardchn+=md_sngchn; } md_numchn=md_hardchn+md_softchn; } /* Limits the number of hardware voices to the specified amount. This function should only be used by the low-level drivers. */ static void LimitSoftVoices(int limit) { int t=0; if ((md_mode & DMODE_SOFT_SNDFX) && (md_sfxchn>limit)) md_sfxchn=limit; if ((md_mode & DMODE_SOFT_MUSIC) && (md_sngchn>limit)) md_sngchn=limit; if (md_mode & DMODE_SOFT_SNDFX) md_softchn=md_sfxchn; else md_softchn=0; if (md_mode & DMODE_SOFT_MUSIC) md_softchn+=md_sngchn; while (md_softchn>limit) { if (++t & 1) { if ((md_mode & DMODE_SOFT_SNDFX) && (md_sfxchn>4)) md_sfxchn--; } else { if ((md_mode & DMODE_SOFT_MUSIC) && (md_sngchn>8)) md_sngchn--; } if (!(md_mode & DMODE_SOFT_SNDFX)) md_softchn=md_sfxchn; else md_softchn=0; if (!(md_mode & DMODE_SOFT_MUSIC)) md_softchn+=md_sngchn; } md_numchn=md_hardchn+md_softchn; } /* Note: 'type' indicates whether the returned value should be for music or for sound effects. */ ULONG MD_SampleSpace(int type) { if(type==MD_MUSIC) type=(md_mode & DMODE_SOFT_MUSIC)?MD_SOFTWARE:MD_HARDWARE; else if(type==MD_SNDFX) type=(md_mode & DMODE_SOFT_SNDFX)?MD_SOFTWARE:MD_HARDWARE; return md_driver->FreeSampleSpace(type); } ULONG MD_SampleLength(int type,SAMPLE* s) { if(type==MD_MUSIC) type=(md_mode & DMODE_SOFT_MUSIC)?MD_SOFTWARE:MD_HARDWARE; else if(type==MD_SNDFX) type=(md_mode & DMODE_SOFT_SNDFX)?MD_SOFTWARE:MD_HARDWARE; return md_driver->RealSampleLength(type,s); } MIKMODAPI CHAR* MikMod_InfoDriver(void) { int t; size_t len=0; MDRIVER *l; CHAR *list=NULL; MUTEX_LOCK(lists); /* compute size of buffer */ for(l=firstdriver;l;l=l->next) len+=4+(l->next?1:0)+strlen(l->Version); if(len) if((list=MikMod_malloc(len*sizeof(CHAR)))) { list[0]=0; /* list all registered device drivers : */ for(t=1,l=firstdriver;l;l=l->next,t++) sprintf(list,(l->next)?"%s%2d %s\n":"%s%2d %s", list,t,l->Version); } MUTEX_UNLOCK(lists); return list; } void _mm_registerdriver(struct MDRIVER* drv) { MDRIVER *cruise = firstdriver; /* don't register a MISSING() driver */ if ((drv->Name) && (drv->Version)) { if (cruise) { if ( cruise == drv ) return; while(cruise->next) { cruise = cruise->next; if ( cruise == drv ) return; } cruise->next = drv; } else firstdriver = drv; } } MIKMODAPI void MikMod_RegisterDriver(struct MDRIVER* drv) { /* if we try to register an invalid driver, or an already registered driver, ignore this attempt */ if ((!drv)||(drv->next)||(!drv->Name)) return; MUTEX_LOCK(lists); _mm_registerdriver(drv); MUTEX_UNLOCK(lists); } MIKMODAPI int MikMod_DriverFromAlias(CHAR *alias) { int rank=1; MDRIVER *cruise; MUTEX_LOCK(lists); cruise=firstdriver; while(cruise) { if (cruise->Alias) { if (!(strcasecmp(alias,cruise->Alias))) break; rank++; } cruise=cruise->next; } if(!cruise) rank=0; MUTEX_UNLOCK(lists); return rank; } MIKMODAPI MDRIVER *MikMod_DriverByOrdinal(int ordinal) { MDRIVER *cruise; /* Allow only driver ordinals > 0 */ if (!ordinal) return 0; MUTEX_LOCK(lists); cruise = firstdriver; while (cruise && --ordinal) cruise = cruise->next; MUTEX_UNLOCK(lists); return cruise; } SWORD MD_SampleLoad(SAMPLOAD* s, int type) { SWORD result; if(type==MD_MUSIC) type=(md_mode & DMODE_SOFT_MUSIC)?MD_SOFTWARE:MD_HARDWARE; else if(type==MD_SNDFX) type=(md_mode & DMODE_SOFT_SNDFX)?MD_SOFTWARE:MD_HARDWARE; SL_Init(s); result=md_driver->SampleLoad(s,type); SL_Exit(s); return result; } void MD_SampleUnload(SWORD handle) { md_driver->SampleUnload(handle); } MIKMODAPI MikMod_player_t MikMod_RegisterPlayer(MikMod_player_t player) { MikMod_player_t result; MUTEX_LOCK(vars); result=md_player; md_player=player; MUTEX_UNLOCK(vars); return result; } MIKMODAPI void MikMod_Update(void) { MUTEX_LOCK(vars); if(isplaying) { if((!pf)||(!pf->forbid)) md_driver->Update(); else { if (md_driver->Pause) md_driver->Pause(); } } MUTEX_UNLOCK(vars); } void Voice_SetVolume_internal(SBYTE voice,UWORD vol) { ULONG tmp; if((voice<0)||(voice>=md_numchn)) return; /* range checks */ if(md_musicvolume>128) md_musicvolume=128; if(md_sndfxvolume>128) md_sndfxvolume=128; if(md_volume>128) md_volume=128; tmp=(ULONG)vol*(ULONG)md_volume* ((voiceVoiceSetVolume(voice,tmp/16384UL); } MIKMODAPI void Voice_SetVolume(SBYTE voice,UWORD vol) { MUTEX_LOCK(vars); Voice_SetVolume_internal(voice,vol); MUTEX_UNLOCK(vars); } MIKMODAPI UWORD Voice_GetVolume(SBYTE voice) { UWORD result=0; MUTEX_LOCK(vars); if((voice>=0)&&(voiceVoiceGetVolume(voice); MUTEX_UNLOCK(vars); return result; } void Voice_SetFrequency_internal(SBYTE voice,ULONG frq) { if((voice<0)||(voice>=md_numchn)) return; if((md_sample[voice])&&(md_sample[voice]->divfactor)) frq/=md_sample[voice]->divfactor; md_driver->VoiceSetFrequency(voice,frq); } MIKMODAPI void Voice_SetFrequency(SBYTE voice,ULONG frq) { MUTEX_LOCK(vars); Voice_SetFrequency_internal(voice,frq); MUTEX_UNLOCK(vars); } MIKMODAPI ULONG Voice_GetFrequency(SBYTE voice) { ULONG result=0; MUTEX_LOCK(vars); if((voice>=0)&&(voiceVoiceGetFrequency(voice); MUTEX_UNLOCK(vars); return result; } void Voice_SetPanning_internal(SBYTE voice,ULONG pan) { if((voice<0)||(voice>=md_numchn)) return; if(pan!=PAN_SURROUND) { if(md_pansep>128) md_pansep=128; if(md_mode & DMODE_REVERSE) pan=255-pan; pan = (((SWORD)(pan-128)*md_pansep)/128)+128; } md_driver->VoiceSetPanning(voice, pan); } MIKMODAPI void Voice_SetPanning(SBYTE voice,ULONG pan) { #ifdef MIKMOD_DEBUG if((pan!=PAN_SURROUND)&&((pan<0)||(pan>255))) fprintf(stderr,"\rVoice_SetPanning called with pan=%ld\n",(long)pan); #endif MUTEX_LOCK(vars); Voice_SetPanning_internal(voice,pan); MUTEX_UNLOCK(vars); } MIKMODAPI ULONG Voice_GetPanning(SBYTE voice) { ULONG result=PAN_CENTER; MUTEX_LOCK(vars); if((voice>=0)&&(voiceVoiceGetPanning(voice); MUTEX_UNLOCK(vars); return result; } void Voice_Play_internal(SBYTE voice,SAMPLE* s,ULONG start) { ULONG repend; if((voice<0)||(voice>=md_numchn)) return; md_sample[voice]=s; repend=s->loopend; if(s->flags&SF_LOOP) /* repend can't be bigger than size */ if(repend>s->length) repend=s->length; md_driver->VoicePlay(voice,s->handle,start,s->length,s->loopstart,repend,s->flags); } MIKMODAPI void Voice_Play(SBYTE voice,SAMPLE* s,ULONG start) { if(start>s->length) return; MUTEX_LOCK(vars); Voice_Play_internal(voice,s,start); MUTEX_UNLOCK(vars); } void Voice_Stop_internal(SBYTE voice) { if((voice<0)||(voice>=md_numchn)) return; if(voice>=md_sngchn) /* It is a sound effects channel, so flag the voice as non-critical! */ sfxinfo[voice-md_sngchn]=0; md_driver->VoiceStop(voice); } MIKMODAPI void Voice_Stop(SBYTE voice) { MUTEX_LOCK(vars); Voice_Stop_internal(voice); MUTEX_UNLOCK(vars); } int Voice_Stopped_internal(SBYTE voice) { if((voice<0)||(voice>=md_numchn)) return 0; return(md_driver->VoiceStopped(voice)); } MIKMODAPI int Voice_Stopped(SBYTE voice) { int result; MUTEX_LOCK(vars); result=Voice_Stopped_internal(voice); MUTEX_UNLOCK(vars); return result; } MIKMODAPI SLONG Voice_GetPosition(SBYTE voice) { SLONG result=0; MUTEX_LOCK(vars); if((voice>=0)&&(voiceVoiceGetPosition) result=(md_driver->VoiceGetPosition(voice)); else result=-1; } MUTEX_UNLOCK(vars); return result; } MIKMODAPI ULONG Voice_RealVolume(SBYTE voice) { ULONG result=0; MUTEX_LOCK(vars); if((voice>=0)&&(voiceVoiceRealVolume) result=(md_driver->VoiceRealVolume(voice)); MUTEX_UNLOCK(vars); return result; } extern MikMod_callback_t vc_callback; MIKMODAPI void VC_SetCallback(MikMod_callback_t callback) { vc_callback = callback; } static int _mm_init(CHAR *cmdline) { UWORD t; _mm_critical = 1; /* if md_device==0, try to find a device number */ if(!md_device) { cmdline=NULL; for(t=1,md_driver=firstdriver;md_driver;md_driver=md_driver->next,t++) if(md_driver->IsPresent()) break; if(!md_driver) { _mm_errno = MMERR_DETECTING_DEVICE; if(_mm_errorhandler) _mm_errorhandler(); md_driver = &drv_nos; return 1; } md_device = t; } else { /* if n>0, use that driver */ for(t=1,md_driver=firstdriver;(md_driver)&&(t!=md_device);md_driver=md_driver->next) t++; if(!md_driver) { _mm_errno = MMERR_INVALID_DEVICE; if(_mm_errorhandler) _mm_errorhandler(); md_driver = &drv_nos; return 1; } /* arguments here might be necessary for the presence check to succeed */ if(cmdline&&(md_driver->CommandLine)) md_driver->CommandLine(cmdline); if(!md_driver->IsPresent()) { _mm_errno = MMERR_DETECTING_DEVICE; if(_mm_errorhandler) _mm_errorhandler(); md_driver = &drv_nos; return 1; } } olddevice = md_device; if(md_driver->Init()) { MikMod_Exit_internal(); if(_mm_errorhandler) _mm_errorhandler(); return 1; } initialized=1; _mm_critical=0; return 0; } MIKMODAPI int MikMod_Init(CHAR *cmdline) { int result; MUTEX_LOCK(vars); MUTEX_LOCK(lists); result=_mm_init(cmdline); MUTEX_UNLOCK(lists); MUTEX_UNLOCK(vars); return result; } void MikMod_Exit_internal(void) { MikMod_DisableOutput_internal(); md_driver->Exit(); md_numchn = md_sfxchn = md_sngchn = 0; md_driver = &drv_nos; if(sfxinfo) MikMod_free(sfxinfo); if(md_sample) MikMod_free(md_sample); md_sample = NULL; sfxinfo = NULL; initialized = 0; } MIKMODAPI void MikMod_Exit(void) { MUTEX_LOCK(vars); MUTEX_LOCK(lists); MikMod_Exit_internal(); MUTEX_UNLOCK(lists); MUTEX_UNLOCK(vars); } /* Reset the driver using the new global variable settings. If the driver has not been initialized, it will be now. */ static int _mm_reset(CHAR *cmdline) { int wasplaying = 0; if(!initialized) return _mm_init(cmdline); if (isplaying) { wasplaying = 1; md_driver->PlayStop(); } if((!md_driver->Reset)||(md_device != olddevice)) { /* md_driver->Reset was NULL, or md_device was changed, so do a full reset of the driver. */ md_driver->Exit(); if(_mm_init(cmdline)) { MikMod_Exit_internal(); if(_mm_errno) if(_mm_errorhandler) _mm_errorhandler(); return 1; } } else { if(md_driver->Reset()) { MikMod_Exit_internal(); if(_mm_errno) if(_mm_errorhandler) _mm_errorhandler(); return 1; } } if (wasplaying) md_driver->PlayStart(); return 0; } MIKMODAPI int MikMod_Reset(CHAR *cmdline) { int result; MUTEX_LOCK(vars); MUTEX_LOCK(lists); result=_mm_reset(cmdline); MUTEX_UNLOCK(lists); MUTEX_UNLOCK(vars); return result; } /* If either parameter is -1, the current set value will be retained. */ int MikMod_SetNumVoices_internal(int music, int sfx) { int resume = 0; int t, oldchn = 0; if((!music)&&(!sfx)) return 1; _mm_critical = 1; if(isplaying) { MikMod_DisableOutput_internal(); oldchn = md_numchn; resume = 1; } if(sfxinfo) MikMod_free(sfxinfo); if(md_sample) MikMod_free(md_sample); md_sample = NULL; sfxinfo = NULL; if(music!=-1) md_sngchn = music; if(sfx!=-1) md_sfxchn = sfx; md_numchn = md_sngchn + md_sfxchn; LimitHardVoices(md_driver->HardVoiceLimit); LimitSoftVoices(md_driver->SoftVoiceLimit); if(md_driver->SetNumVoices()) { MikMod_Exit_internal(); if(_mm_errno) if(_mm_errorhandler!=NULL) _mm_errorhandler(); md_numchn = md_softchn = md_hardchn = md_sfxchn = md_sngchn = 0; return 1; } if(md_sngchn+md_sfxchn) md_sample=(SAMPLE**)MikMod_calloc(md_sngchn+md_sfxchn,sizeof(SAMPLE*)); if(md_sfxchn) sfxinfo = (UBYTE *)MikMod_calloc(md_sfxchn,sizeof(UBYTE)); /* make sure the player doesn't start with garbage */ for(t=oldchn;tPlayStart()) return 1; isplaying = 1; } _mm_critical = 0; return 0; } MIKMODAPI int MikMod_EnableOutput(void) { int result; MUTEX_LOCK(vars); result=MikMod_EnableOutput_internal(); MUTEX_UNLOCK(vars); return result; } void MikMod_DisableOutput_internal(void) { if(isplaying && md_driver) { isplaying = 0; md_driver->PlayStop(); } } MIKMODAPI void MikMod_DisableOutput(void) { MUTEX_LOCK(vars); MikMod_DisableOutput_internal(); MUTEX_UNLOCK(vars); } int MikMod_Active_internal(void) { return isplaying; } MIKMODAPI int MikMod_Active(void) { int result; MUTEX_LOCK(vars); result=MikMod_Active_internal(); MUTEX_UNLOCK(vars); return result; } /* Plays a sound effects sample. Picks a voice from the number of voices allocated for use as sound effects (loops through voices, skipping all active criticals). Returns the voice that the sound is being played on. */ static SBYTE Sample_Play_internal(SAMPLE *s,ULONG start,UBYTE flags) { int orig=sfxpool;/* for cases where all channels are critical */ int c; if(!md_sfxchn) return -1; if(s->volume>64) s->volume = 64; /* check the first location after sfxpool */ do { if(sfxinfo[sfxpool]&SFX_CRITICAL) { if(md_driver->VoiceStopped(c=sfxpool+md_sngchn)) { sfxinfo[sfxpool]=flags; Voice_Play_internal(c,s,start); md_driver->VoiceSetVolume(c,s->volume<<2); Voice_SetPanning_internal(c,s->panning); md_driver->VoiceSetFrequency(c,s->speed); sfxpool++; if(sfxpool>=md_sfxchn) sfxpool=0; return c; } } else { sfxinfo[sfxpool]=flags; Voice_Play_internal(c=sfxpool+md_sngchn,s,start); md_driver->VoiceSetVolume(c,s->volume<<2); Voice_SetPanning_internal(c,s->panning); md_driver->VoiceSetFrequency(c,s->speed); sfxpool++; if(sfxpool>=md_sfxchn) sfxpool=0; return c; } sfxpool++; if(sfxpool>=md_sfxchn) sfxpool = 0; } while(sfxpool!=orig); return -1; } MIKMODAPI SBYTE Sample_Play(SAMPLE *s,ULONG start,UBYTE flags) { SBYTE result; MUTEX_LOCK(vars); result=Sample_Play_internal(s,start,flags); MUTEX_UNLOCK(vars); return result; } MIKMODAPI long MikMod_GetVersion(void) { return LIBMIKMOD_VERSION; } /*========== MT-safe stuff */ #ifdef HAVE_PTHREAD #define INIT_MUTEX(name) \ pthread_mutex_t _mm_mutex_##name=PTHREAD_MUTEX_INITIALIZER #elif defined(__OS2__)||defined(__EMX__) #define INIT_MUTEX(name) \ HMTX _mm_mutex_##name #elif defined(WIN32) #define INIT_MUTEX(name) \ HANDLE _mm_mutex_##name #else #define INIT_MUTEX(name) \ void *_mm_mutex_##name = NULL #endif INIT_MUTEX(vars); INIT_MUTEX(lists); MIKMODAPI int MikMod_InitThreads(void) { static int firstcall=1; static int result=0; if (firstcall) { firstcall=0; #ifdef HAVE_PTHREAD result=1; #elif defined(__OS2__)||defined(__EMX__) if(DosCreateMutexSem((PSZ)NULL,&_mm_mutex_lists,0,0) || DosCreateMutexSem((PSZ)NULL,&_mm_mutex_vars,0,0)) { _mm_mutex_lists=_mm_mutex_vars=(HMTX)NULL; result=0; } else result=1; #elif defined(WIN32) if((!(_mm_mutex_lists=CreateMutex(NULL,FALSE,"libmikmod(lists)")))|| (!(_mm_mutex_vars=CreateMutex(NULL,FALSE,"libmikmod(vars)")))) result=0; else result=1; #endif } return result; } MIKMODAPI void MikMod_Unlock(void) { MUTEX_UNLOCK(lists); MUTEX_UNLOCK(vars); } MIKMODAPI void MikMod_Lock(void) { MUTEX_LOCK(vars); MUTEX_LOCK(lists); } /*========== Parameter extraction helper */ CHAR *MD_GetAtom(CHAR *atomname,CHAR *cmdline,int implicit) { CHAR *ret=NULL; if(cmdline) { CHAR *buf=strstr(cmdline,atomname); if((buf)&&((buf==cmdline)||(*(buf-1)==','))) { CHAR *ptr=buf+strlen(atomname); if(*ptr=='=') { for(buf=++ptr;(*ptr)&&((*ptr)!=',');ptr++); ret=MikMod_malloc((1+ptr-buf)*sizeof(CHAR)); if(ret) strncpy(ret,buf,ptr-buf); } else if((*ptr==',')||(!*ptr)) { if(implicit) { ret=MikMod_malloc((1+ptr-buf)*sizeof(CHAR)); if(ret) strncpy(ret,buf,ptr-buf); } } } } return ret; } #if 0 #if defined unix || (defined __APPLE__ && defined __MACH__) /*========== Posix helper functions */ /* Check if the file is a regular or nonexistant file (or a link to a such a file), and that, should the calling program be setuid, the access rights are reasonable. Returns 1 if it is safe to rewrite the file, 0 otherwise. The goal is to prevent a setuid root libmikmod application from overriding files like /etc/passwd with digital sound... */ int MD_Access(CHAR *filename) { struct stat buf; if(!stat(filename,&buf)) { /* not a regular file ? */ if(!S_ISREG(buf.st_mode)) return 0; /* more than one hard link to the file ? */ if(buf.st_nlink>1) return 0; /* check access rights with the real user and group id */ if(getuid()==buf.st_uid) { if(!(buf.st_mode&S_IWUSR)) return 0; } else if(getgid()==buf.st_gid) { if(!(buf.st_mode&S_IWGRP)) return 0; } else if(!(buf.st_mode&S_IWOTH)) return 0; } return 1; } /* Drop all root privileges we might have */ int MD_DropPrivileges(void) { if(!geteuid()) { if(getuid()) { /* we are setuid root -> drop setuid to become the real user */ if(setuid(getuid())) return 1; } else { /* we are run as root -> drop all and become user 'nobody' */ struct passwd *nobody; int uid; if(!(nobody=getpwnam("nobody"))) return 1; /* no such user ? */ uid=nobody->pw_uid; if (!uid) /* user 'nobody' has root privileges ? weird... */ return 1; if (setuid(uid)) return 1; } } return 0; } #endif #endif /* ex:set ts=4: */