/* $NetBSD: ntp_filegen.c,v 1.3 1998/03/06 18:17:21 christos Exp $ */ /* * ntp_filegen.c,v 3.12 1994/01/25 19:06:11 kardel Exp * * implements file generations support for NTP * logfiles and statistic files * * * Copyright (C) 1992, 1996 by Rainer Pruy * Friedrich-Alexander Universität Erlangen-Nürnberg, Germany * * This code may be modified and used freely * provided credits remain intact. */ #ifdef HAVE_CONFIG_H #include #endif #include #include #include #include #include "ntpd.h" #include "ntp_io.h" #include "ntp_string.h" #include "ntp_calendar.h" #include "ntp_filegen.h" #include "ntp_stdlib.h" /* * NTP is intended to run long periods of time without restart. * Thus log and statistic files generated by NTP will grow large. * * this set of routines provides a central interface * to generating files using file generations * * the generation of a file is changed according to file generation type */ /* * to check reason on open failure */ #ifndef SYS_WINNT extern int errno; #endif /* SYS_WINNT */ /* * imported from timer */ extern u_long current_time; /* * redefine this if your system dislikes filename suffixes like * X.19910101 or X.1992W50 or .... */ #define SUFFIX_SEP '.' /* * other constants */ #define FGEN_AGE_SECS (24*60*60) /* life time of FILEGEN_AGE in seconds */ #ifdef DEBUG extern int debug; #endif static void filegen_open P((FILEGEN *, u_long)); static int valid_fileref P((char *, char *)); #ifdef UNUSED static FILEGEN *filegen_unregister P((char *)); #endif /* UNUSED */ /* * open a file generation according to the current settings of gen * will also provide a link to basename if requested to do so */ static void filegen_open(gen, newid) FILEGEN *gen; u_long newid; { char *filename; char *basename; u_int len; FILE *fp; struct calendar cal; len = strlen(gen->prefix) + strlen(gen->basename) + 1; basename = emalloc(len); sprintf(basename, "%s%s", gen->prefix, gen->basename); switch(gen->type) { default: msyslog(LOG_ERR, "unsupported file generations type %d for \"%s\" - reverting to FILEGEN_NONE", gen->type, basename); gen->type = FILEGEN_NONE; /*FALLTHROUGH*/ case FILEGEN_NONE: filename = emalloc(len); sprintf(filename,"%s", basename); break; case FILEGEN_PID: filename = emalloc(len + 1 + 1 + 10); sprintf(filename,"%s%c#%ld", basename, SUFFIX_SEP, newid); break; case FILEGEN_DAY: /* You can argue here in favor of using MJD, but * I would assume it to be easier for humans to interpret dates * in a format they are used to in everyday life. */ caljulian(newid,&cal); filename = emalloc(len + 1 + 4 + 2 + 2); sprintf(filename, "%s%c%04d%02d%02d", basename, SUFFIX_SEP, cal.year, cal.month, cal.monthday); break; case FILEGEN_WEEK: /* * This is still a hack * - the term week is not correlated to week as it is used * normally - it just refers to a period of 7 days * starting at Jan 1 - 'weeks' are counted starting from zero */ caljulian(newid,&cal); filename = emalloc(len + 1 + 4 + 1 + 2); sprintf(filename, "%s%c%04dw%02d", basename, SUFFIX_SEP, cal.year, cal.yearday / 7); break; case FILEGEN_MONTH: caljulian(newid,&cal); filename = emalloc(len + 1 + 4 + 2); sprintf(filename, "%s%c%04d%02d", basename, SUFFIX_SEP, cal.year, cal.month); break; case FILEGEN_YEAR: caljulian(newid,&cal); filename = emalloc(len + 1 + 4); sprintf(filename, "%s%c%04d", basename, SUFFIX_SEP, cal.year); break; case FILEGEN_AGE: filename = emalloc(len + 1 + 2 + 10); sprintf(filename, "%s%ca%08ld", basename, SUFFIX_SEP, newid); break; } if (gen->type != FILEGEN_NONE) { /* * check for existence of a file with name 'basename' * as we disallow such a file * if FGEN_FLAG_LINK is set create a link */ struct stat stats; /* * try to resolve name collisions */ static u_long conflicts = 0; #ifndef S_ISREG #define S_ISREG(mode) (((mode) & S_IFREG) == S_IFREG) #endif if (stat(basename, &stats) == 0) { /* Hm, file exists... */ if (S_ISREG(stats.st_mode)) { if (stats.st_nlink <= 1) { /* * Oh, it is not linked - try to save it */ char *savename = emalloc(len + 1 + 1 + 10 + 10); sprintf(savename, "%s%c%dC%lu", basename, SUFFIX_SEP, (int) getpid(), (u_long)conflicts++); if (rename(basename, savename) != 0) msyslog(LOG_ERR," couldn't save %s: %m", basename); free(savename); } else { /* * there is at least a second link tpo this file * just remove the conflicting one */ #if !defined(VMS) if (unlink(basename) != 0) #else if (delete(basename) != 0) #endif msyslog(LOG_ERR, "couldn't unlink %s: %m", basename); } } else { /* * Ehh? Not a regular file ?? strange !!!! */ msyslog(LOG_ERR, "expected regular file for %s (found mode 0%o)", basename, stats.st_mode); } } else { /* * stat(..) failed, but it is absolutely correct for * 'basename' not to exist */ if (errno != ENOENT) msyslog(LOG_ERR,"stat(%s) failed: %m", basename); } } /* * now, try to open new file generation... */ fp = fopen(filename, "a"); #ifdef DEBUG if (debug > 3) printf("opening filegen (type=%d/id=%lu) \"%s\"\n", gen->type, (u_long)newid, filename); #endif if (fp == NULL) { /* open failed -- keep previous state * * If the file was open before keep the previous generation. * This will cause output to end up in the 'wrong' file, * but I think this is still better than loosing output * * ignore errors due to missing directories */ if (errno != ENOENT) msyslog(LOG_ERR, "can't open %s: %m", filename); } else { if (gen->fp != NULL) { fclose(gen->fp); } gen->fp = fp; gen->id = newid; if (gen->flag & FGEN_FLAG_LINK) { /* * need to link file to basename * have to use hardlink for now as I want to allow * gen->basename spanning directory levels * this would make it more complex to get the correct filename * for symlink * * Ok, it would just mean taking the part following the last '/' * in the name.... Should add it later.... */ /* Windows NT does not support file links -Greg Schueman 1/18/97 */ #if !defined(VMS) && !defined(SYS_WINNT) && !defined (SYS_VXWORKS) if (link(filename, basename) != 0) { if (errno != EEXIST) #else { #ifndef SYS_WINNT errno = 0; /* On VMS, don't support FGEN_FLAG_LINK */ #else SetLastError(0); /* On WinNT, don't support FGEN_FLAG_LINK */ #endif /* SYS_WINNT */ #endif /* VMS */ msyslog(LOG_ERR, "can't link(%s, %s): %m", filename, basename); } } /* flags & FGEN_FLAG_LINK */ } /* else fp == NULL */ free(basename); free(filename); return; } /* * this function sets up gen->fp to point to the correct * generation of the file for the time specified by 'now' * * 'now' usually is interpreted as second part of a l_fp as is in the cal... * library routines */ void filegen_setup(gen,now) FILEGEN *gen; u_long now; { u_long new_gen = ~ (u_long) 0; struct calendar cal; if (!(gen->flag & FGEN_FLAG_ENABLED)) { if (gen->fp != NULL) fclose(gen->fp); return; } switch (gen->type) { case FILEGEN_NONE: if (gen->fp != NULL) return; /* file already open */ break; case FILEGEN_PID: new_gen = getpid(); break; case FILEGEN_DAY: caljulian(now, &cal); cal.hour = cal.minute = cal.second = 0; new_gen = caltontp(&cal); break; case FILEGEN_WEEK: /* Would be nice to have a calweekstart() routine */ /* so just use a hack ... */ /* just round time to integral 7 days period for actual year */ new_gen = now - (now - calyearstart(now)) % TIMES7(SECSPERDAY) + 60; /* * just to be sure - * the computation above would fail in the presence of leap seconds * so at least carry the date to the next day (+60 (seconds)) * and go back to the start of the day via calendar computations */ caljulian(new_gen, &cal); cal.hour = cal.minute = cal.second = 0; new_gen = caltontp(&cal); break; case FILEGEN_MONTH: caljulian(now, &cal); cal.yearday -= cal.monthday - 1; cal.monthday = 1; cal.hour = cal.minute = cal.second = 0; new_gen = caltontp(&cal); break; case FILEGEN_YEAR: new_gen = calyearstart(now); break; case FILEGEN_AGE: new_gen = current_time - (current_time % FGEN_AGE_SECS); break; } /* * try to open file if not yet open * reopen new file generation file on change of generation id */ if (gen->fp == NULL || gen->id != new_gen) { filegen_open(gen, new_gen); } } /* * change settings for filegen files */ void filegen_config(gen,basename,type,flag) FILEGEN *gen; char *basename; u_int type; u_int flag; { /* * if nothing would be changed... */ if ((basename == gen->basename || strcmp(basename,gen->basename) == 0) && type == gen->type && flag == gen->flag) return; /* * validate parameters */ if (!valid_fileref(gen->prefix,basename)) return; if (gen->fp != NULL) fclose(gen->fp); #ifdef DEBUG if (debug > 2) printf("configuring filegen:\n\tprefix:\t%s\n\tbasename:\t%s -> %s\n\ttype:\t%d -> %d\n\tflag: %x -> %x\n", gen->prefix, gen->basename, basename, gen->type, type, gen->flag, flag); #endif if (gen->basename != basename || strcmp(gen->basename, basename) != 0) { free(gen->basename); gen->basename = emalloc(strlen(basename) + 1); strcpy(gen->basename, basename); } gen->type = type; gen->flag = flag; /* * make filegen use the new settings * special action is only required when a generation file * is currently open * otherwise the new settings will be used anyway at the next open */ if (gen->fp != NULL) { l_fp now; get_systime(&now); filegen_setup(gen, now.l_ui); } } /* * check whether concatenating prefix and basename * yields a legal filename */ static int valid_fileref(prefix,basename) char *prefix, *basename; { /* * prefix cannot be changed dynamically * (within the context of filegen) * so just reject basenames containing '..' * * ASSUMPTION: * file system parts 'below' prefix may be * specified without infringement of security * * restricing prefix to legal values * has to be ensured by other means * (however, it would be possible to perform some checks here...) */ register char *p = basename; /* * Just to catch, dumb errors opening up the world... */ if (prefix == NULL || *prefix == '\0') return 0; if (basename == NULL) return 0; for (p = basename; p; p = strchr(p, '/')) { if (*p == '.' && *(p+1) == '.' && (*(p+2) == '\0' || *(p+2) == '/')) return 0; } return 1; } /* * filegen registry */ static struct filegen_entry { char *name; FILEGEN *filegen; struct filegen_entry *next; } *filegen_registry = NULL; FILEGEN * filegen_get(name) char *name; { struct filegen_entry *f = filegen_registry; while(f) { if (f->name == name || strcmp(name, f->name) == 0) { #ifdef XXX /* this gives the Alpha compiler fits */ if (debug > 3) printf("filegen_get(\"%s\") = %x\n", name, (u_int)f->filegen); #endif return f->filegen; } f = f->next; } #ifdef DEBUG if (debug > 3) printf("filegen_get(\"%s\") = NULL\n", name); #endif return NULL; } void filegen_register(name, filegen) char *name; FILEGEN *filegen; { struct filegen_entry **f = &filegen_registry; #ifdef XXX /* this gives the Alpha compiler fits */ if (debug > 3) printf("filegen_register(\"%s\",%x)\n", name, (u_int)filegen); #endif while (*f) { if ((*f)->name == name || strcmp(name, (*f)->name) == 0) { #ifdef XXX /* this gives the Alpha compiler fits */ if (debug > 4) { printf("replacing filegen %x\n", (u_int)(*f)->filegen); } #endif (*f)->filegen = filegen; return; } f = &((*f)->next); } *f = (struct filegen_entry *) emalloc(sizeof(struct filegen_entry)); if (*f) { (*f)->next = NULL; (*f)->name = emalloc(strlen(name) + 1); strcpy((*f)->name, name); (*f)->filegen = filegen; #ifdef DEBUG if (debug > 5) { printf("adding new filegen\n"); } #endif } return; } #ifdef UNUSED static FILEGEN * filegen_unregister(name) char *name; { struct filegen_entry **f = &filegen_registry; #ifdef DEBUG if (debug > 3) printf("filegen_unregister(\"%s\")\n", name); #endif while (*f) { if (strcmp((*f)->name,name) == 0) { struct filegen_entry *ff = *f; FILEGEN *fg; *f = (*f)->next; fg = ff->filegen; free(ff->name); free(ff); return fg; } f = &((*f)->next); } return NULL; } #endif /* UNUSED */