/* Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /* * htcacheclean.c: simple program for cleaning of * the disk cache of the Apache HTTP server * * Contributed by Andreas Steinmetz <ast domdv.de> * 8 Oct 2004 */ #include "apr.h" #include "apr_lib.h" #include "apr_strings.h" #include "apr_file_io.h" #include "apr_file_info.h" #include "apr_pools.h" #include "apr_hash.h" #include "apr_thread_proc.h" #include "apr_signal.h" #include "apr_getopt.h" #include "apr_ring.h" #include "apr_date.h" #include "../modules/cache/mod_disk_cache.h" #if APR_HAVE_UNISTD_H #include <unistd.h> #endif #if APR_HAVE_STDLIB_H #include <stdlib.h> #endif /* define the following for debugging */ #undef DEBUG /* * Note: on Linux delays <= 2ms are busy waits without * scheduling, so never use a delay <= 2ms below */ #define NICE_DELAY 10000 /* usecs */ #define DELETE_NICE 10 /* be nice after this amount of delete ops */ #define STAT_ATTEMPTS 10 /* maximum stat attempts for a file */ #define STAT_DELAY 5000 /* usecs */ #define HEADER 1 /* headers file */ #define DATA 2 /* body file */ #define TEMP 4 /* temporary file */ #define HEADERDATA (HEADER|DATA) #define MAXDEVIATION 3600 /* secs */ #define SECS_PER_MIN 60 #define KBYTE 1024 #define MBYTE 1048576 #define GBYTE 1073741824 #define DIRINFO (APR_FINFO_MTIME|APR_FINFO_SIZE|APR_FINFO_TYPE|APR_FINFO_LINK) typedef struct _direntry { APR_RING_ENTRY(_direntry) link; int type; /* type of file/fileset: TEMP, HEADER, DATA, HEADERDATA */ apr_time_t htime; /* headers file modification time */ apr_time_t dtime; /* body file modification time */ apr_off_t hsize; /* headers file size */ apr_off_t dsize; /* body or temporary file size */ char *basename; /* file/fileset base name */ } DIRENTRY; typedef struct _entry { APR_RING_ENTRY(_entry) link; apr_time_t expire; /* cache entry exiration time */ apr_time_t response_time; /* cache entry time of last response to client */ apr_time_t htime; /* headers file modification time */ apr_time_t dtime; /* body file modification time */ apr_off_t hsize; /* headers file size */ apr_off_t dsize; /* body or temporary file size */ char *basename; /* fileset base name */ } ENTRY; static int delcount; /* file deletion count for nice mode */ static int interrupted; /* flag: true if SIGINT or SIGTERM occurred */ static int realclean; /* flag: true means user said apache is not running */ static int verbose; /* flag: true means print statistics */ static int benice; /* flag: true means nice mode is activated */ static int dryrun; /* flag: true means dry run, don't actually delete anything */ static int deldirs; /* flag: true means directories should be deleted */ static int baselen; /* string length of the path to the proxy directory */ static apr_time_t now; /* start time of this processing run */ static apr_file_t *errfile; /* stderr file handle */ static apr_off_t unsolicited; /* file size summary for deleted unsolicited files */ static APR_RING_ENTRY(_entry) root; /* ENTRY ring anchor */ /* short program name as called */ static const char *shortname = "htcacheclean"; #ifdef DEBUG /* * fake delete for debug purposes */ #define apr_file_remove fake_file_remove static void fake_file_remove(char *pathname, apr_pool_t *p) { apr_finfo_t info; /* stat and printing to simulate some deletion system load and to display what would actually have happened */ apr_stat(&info, pathname, DIRINFO, p); apr_file_printf(errfile, "would delete %s" APR_EOL_STR, pathname); } #endif /* * called on SIGINT or SIGTERM */ static void setterm(int unused) { #ifdef DEBUG apr_file_printf(errfile, "interrupt" APR_EOL_STR); #endif interrupted = 1; } /* * called in out of memory condition */ static int oom(int unused) { static int called = 0; /* be careful to call exit() only once */ if (!called) { called = 1; exit(1); } return APR_ENOMEM; } /* * print purge statistics */ static void printstats(apr_off_t total, apr_off_t sum, apr_off_t max, apr_off_t etotal, apr_off_t entries) { char ttype, stype, mtype, utype; apr_off_t tfrag, sfrag, ufrag; if (!verbose) { return; } ttype = 'K'; tfrag = ((total * 10) / KBYTE) % 10; total /= KBYTE; if (total >= KBYTE) { ttype = 'M'; tfrag = ((total * 10) / KBYTE) % 10; total /= KBYTE; } stype = 'K'; sfrag = ((sum * 10) / KBYTE) % 10; sum /= KBYTE; if (sum >= KBYTE) { stype = 'M'; sfrag = ((sum * 10) / KBYTE) % 10; sum /= KBYTE; } mtype = 'K'; max /= KBYTE; if (max >= KBYTE) { mtype = 'M'; max /= KBYTE; } apr_file_printf(errfile, "Statistics:" APR_EOL_STR); if (unsolicited) { utype = 'K'; ufrag = ((unsolicited * 10) / KBYTE) % 10; unsolicited /= KBYTE; if (unsolicited >= KBYTE) { utype = 'M'; ufrag = ((unsolicited * 10) / KBYTE) % 10; unsolicited /= KBYTE; } if (!unsolicited && !ufrag) { ufrag = 1; } apr_file_printf(errfile, "unsolicited size %d.%d%c" APR_EOL_STR, (int)(unsolicited), (int)(ufrag), utype); } apr_file_printf(errfile, "size limit %d.0%c" APR_EOL_STR, (int)(max), mtype); apr_file_printf(errfile, "total size was %d.%d%c, total size now " "%d.%d%c" APR_EOL_STR, (int)(total), (int)(tfrag), ttype, (int)(sum), (int)(sfrag), stype); apr_file_printf(errfile, "total entries was %d, total entries now %d" APR_EOL_STR, (int)(etotal), (int)(entries)); } /* * delete a single file */ static void delete_file(char *path, char *basename, apr_pool_t *pool) { char *nextpath; apr_pool_t *p; if (dryrun) { return; } /* temp pool, otherwise lots of memory could be allocated */ apr_pool_create(&p, pool); nextpath = apr_pstrcat(p, path, "/", basename, NULL); apr_file_remove(nextpath, p); apr_pool_destroy(p); if (benice) { if (++delcount >= DELETE_NICE) { apr_sleep(NICE_DELAY); delcount = 0; } } } /* * delete cache file set */ static void delete_entry(char *path, char *basename, apr_pool_t *pool) { char *nextpath; apr_pool_t *p; if (dryrun) { return; } /* temp pool, otherwise lots of memory could be allocated */ apr_pool_create(&p, pool); nextpath = apr_pstrcat(p, path, "/", basename, CACHE_HEADER_SUFFIX, NULL); apr_file_remove(nextpath, p); nextpath = apr_pstrcat(p, path, "/", basename, CACHE_DATA_SUFFIX, NULL); apr_file_remove(nextpath, p); apr_pool_destroy(p); if (benice) { delcount += 2; if (delcount >= DELETE_NICE) { apr_sleep(NICE_DELAY); delcount = 0; } } } /* * walk the cache directory tree */ static int process_dir(char *path, apr_pool_t *pool) { apr_dir_t *dir; apr_pool_t *p; apr_hash_t *h; apr_hash_index_t *i; apr_file_t *fd; apr_status_t status; apr_finfo_t info; apr_size_t len; apr_time_t current, deviation; char *nextpath, *base, *ext, *orig_basename; APR_RING_ENTRY(_direntry) anchor; DIRENTRY *d, *t, *n; ENTRY *e; int skip, retries; disk_cache_info_t disk_info; APR_RING_INIT(&anchor, _direntry, link); apr_pool_create(&p, pool); h = apr_hash_make(p); fd = NULL; skip = 0; deviation = MAXDEVIATION * APR_USEC_PER_SEC; if (apr_dir_open(&dir, path, p) != APR_SUCCESS) { return 1; } while (apr_dir_read(&info, 0, dir) == APR_SUCCESS && !interrupted) { if (!strcmp(info.name, ".") || !strcmp(info.name, "..")) { continue; } d = apr_pcalloc(p, sizeof(DIRENTRY)); d->basename = apr_pstrcat(p, path, "/", info.name, NULL); APR_RING_INSERT_TAIL(&anchor, d, _direntry, link); } apr_dir_close(dir); if (interrupted) { return 1; } skip = baselen + 1; for (d = APR_RING_FIRST(&anchor); !interrupted && d != APR_RING_SENTINEL(&anchor, _direntry, link); d=n) { n = APR_RING_NEXT(d, link); base = strrchr(d->basename, '/'); if (!base++) { base = d->basename; } ext = strchr(base, '.'); /* there may be temporary files which may be gone before * processing, always skip these if not in realclean mode */ if (!ext && !realclean) { if (!strncasecmp(base, AP_TEMPFILE_BASE, AP_TEMPFILE_BASELEN) && strlen(base) == AP_TEMPFILE_NAMELEN) { continue; } } /* this may look strange but apr_stat() may return errno which * is system dependent and there may be transient failures, * so just blindly retry for a short while */ retries = STAT_ATTEMPTS; status = APR_SUCCESS; do { if (status != APR_SUCCESS) { apr_sleep(STAT_DELAY); } status = apr_stat(&info, d->basename, DIRINFO, p); } while (status != APR_SUCCESS && !interrupted && --retries); /* what may happen here is that apache did create a file which * we did detect but then does delete the file before we can * get file information, so if we don't get any file information * we will ignore the file in this case */ if (status != APR_SUCCESS) { if (!realclean && !interrupted) { continue; } return 1; } if (info.filetype == APR_DIR) { /* Make a copy of the basename, as process_dir modifies it */ orig_basename = apr_pstrdup(pool, d->basename); if (process_dir(d->basename, pool)) { return 1; } /* If asked to delete dirs, do so now. We don't care if it fails. * If it fails, it likely means there was something else there. */ if (deldirs && !dryrun) { apr_dir_remove(orig_basename, pool); } continue; } if (info.filetype != APR_REG) { continue; } if (!ext) { if (!strncasecmp(base, AP_TEMPFILE_BASE, AP_TEMPFILE_BASELEN) && strlen(base) == AP_TEMPFILE_NAMELEN) { d->basename += skip; d->type = TEMP; d->dsize = info.size; apr_hash_set(h, d->basename, APR_HASH_KEY_STRING, d); } continue; } if (!strcasecmp(ext, CACHE_HEADER_SUFFIX)) { *ext = '\0'; d->basename += skip; /* if a user manually creates a '.header' file */ if (d->basename[0] == '\0') { continue; } t = apr_hash_get(h, d->basename, APR_HASH_KEY_STRING); if (t) { d = t; } d->type |= HEADER; d->htime = info.mtime; d->hsize = info.size; apr_hash_set(h, d->basename, APR_HASH_KEY_STRING, d); continue; } if (!strcasecmp(ext, CACHE_DATA_SUFFIX)) { *ext = '\0'; d->basename += skip; /* if a user manually creates a '.data' file */ if (d->basename[0] == '\0') { continue; } t = apr_hash_get(h, d->basename, APR_HASH_KEY_STRING); if (t) { d = t; } d->type |= DATA; d->dtime = info.mtime; d->dsize = info.size; apr_hash_set(h, d->basename, APR_HASH_KEY_STRING, d); } } if (interrupted) { return 1; } path[baselen] = '\0'; for (i = apr_hash_first(p, h); i && !interrupted; i = apr_hash_next(i)) { void *hvalue; apr_uint32_t format; apr_hash_this(i, NULL, NULL, &hvalue); d = hvalue; switch(d->type) { case HEADERDATA: nextpath = apr_pstrcat(p, path, "/", d->basename, CACHE_HEADER_SUFFIX, NULL); if (apr_file_open(&fd, nextpath, APR_FOPEN_READ | APR_FOPEN_BINARY, APR_OS_DEFAULT, p) == APR_SUCCESS) { len = sizeof(format); if (apr_file_read_full(fd, &format, len, &len) == APR_SUCCESS) { if (format == DISK_FORMAT_VERSION) { apr_off_t offset = 0; apr_file_seek(fd, APR_SET, &offset); len = sizeof(disk_cache_info_t); if (apr_file_read_full(fd, &disk_info, len, &len) == APR_SUCCESS) { apr_file_close(fd); e = apr_palloc(pool, sizeof(ENTRY)); APR_RING_INSERT_TAIL(&root, e, _entry, link); e->expire = disk_info.expire; e->response_time = disk_info.response_time; e->htime = d->htime; e->dtime = d->dtime; e->hsize = d->hsize; e->dsize = d->dsize; e->basename = apr_pstrdup(pool, d->basename); break; } else { apr_file_close(fd); } } else if (format == VARY_FORMAT_VERSION) { /* This must be a URL that added Vary headers later, * so kill the orphaned .data file */ apr_file_close(fd); apr_file_remove(apr_pstrcat(p, path, "/", d->basename, CACHE_DATA_SUFFIX, NULL), p); } } else { apr_file_close(fd); } } /* we have a somehow unreadable headers file which is associated * with a data file. this may be caused by apache currently * rewriting the headers file. thus we may delete the file set * either in realclean mode or if the headers file modification * timestamp is not within a specified positive or negative offset * to the current time. */ current = apr_time_now(); if (realclean || d->htime < current - deviation || d->htime > current + deviation) { delete_entry(path, d->basename, p); unsolicited += d->hsize; unsolicited += d->dsize; } break; /* single data and header files may be deleted either in realclean * mode or if their modification timestamp is not within a * specified positive or negative offset to the current time. * this handling is necessary due to possible race conditions * between apache and this process */ case HEADER: current = apr_time_now(); nextpath = apr_pstrcat(p, path, "/", d->basename, CACHE_HEADER_SUFFIX, NULL); if (apr_file_open(&fd, nextpath, APR_FOPEN_READ | APR_FOPEN_BINARY, APR_OS_DEFAULT, p) == APR_SUCCESS) { len = sizeof(format); if (apr_file_read_full(fd, &format, len, &len) == APR_SUCCESS) { if (format == VARY_FORMAT_VERSION) { apr_time_t expires; len = sizeof(expires); apr_file_read_full(fd, &expires, len, &len); apr_file_close(fd); if (expires < current) { delete_entry(path, d->basename, p); } break; } } apr_file_close(fd); } if (realclean || d->htime < current - deviation || d->htime > current + deviation) { delete_entry(path, d->basename, p); unsolicited += d->hsize; } break; case DATA: current = apr_time_now(); if (realclean || d->dtime < current - deviation || d->dtime > current + deviation) { delete_entry(path, d->basename, p); unsolicited += d->dsize; } break; /* temp files may only be deleted in realclean mode which * is asserted above if a tempfile is in the hash array */ case TEMP: delete_file(path, d->basename, p); unsolicited += d->dsize; break; } } if (interrupted) { return 1; } apr_pool_destroy(p); if (benice) { apr_sleep(NICE_DELAY); } if (interrupted) { return 1; } return 0; } /* * purge cache entries */ static void purge(char *path, apr_pool_t *pool, apr_off_t max) { apr_off_t sum, total, entries, etotal; ENTRY *e, *n, *oldest; sum = 0; entries = 0; for (e = APR_RING_FIRST(&root); e != APR_RING_SENTINEL(&root, _entry, link); e = APR_RING_NEXT(e, link)) { sum += e->hsize; sum += e->dsize; entries++; } total = sum; etotal = entries; if (sum <= max) { printstats(total, sum, max, etotal, entries); return; } /* process all entries with a timestamp in the future, this may * happen if a wrong system time is corrected */ for (e = APR_RING_FIRST(&root); e != APR_RING_SENTINEL(&root, _entry, link) && !interrupted;) { n = APR_RING_NEXT(e, link); if (e->response_time > now || e->htime > now || e->dtime > now) { delete_entry(path, e->basename, pool); sum -= e->hsize; sum -= e->dsize; entries--; APR_RING_REMOVE(e, link); if (sum <= max) { if (!interrupted) { printstats(total, sum, max, etotal, entries); } return; } } e = n; } if (interrupted) { return; } /* process all entries with are expired */ for (e = APR_RING_FIRST(&root); e != APR_RING_SENTINEL(&root, _entry, link) && !interrupted;) { n = APR_RING_NEXT(e, link); if (e->expire != APR_DATE_BAD && e->expire < now) { delete_entry(path, e->basename, pool); sum -= e->hsize; sum -= e->dsize; entries--; APR_RING_REMOVE(e, link); if (sum <= max) { if (!interrupted) { printstats(total, sum, max, etotal, entries); } return; } } e = n; } if (interrupted) { return; } /* process remaining entries oldest to newest, the check for an emtpy * ring actually isn't necessary except when the compiler does * corrupt 64bit arithmetics which happend to me once, so better safe * than sorry */ while (sum > max && !interrupted && !APR_RING_EMPTY(&root, _entry, link)) { oldest = APR_RING_FIRST(&root); for (e = APR_RING_NEXT(oldest, link); e != APR_RING_SENTINEL(&root, _entry, link); e = APR_RING_NEXT(e, link)) { if (e->dtime < oldest->dtime) { oldest = e; } } delete_entry(path, oldest->basename, pool); sum -= oldest->hsize; sum -= oldest->dsize; entries--; APR_RING_REMOVE(oldest, link); } if (!interrupted) { printstats(total, sum, max, etotal, entries); } } /* * usage info */ #define NL APR_EOL_STR static void usage(void) { apr_file_printf(errfile, "%s -- program for cleaning the disk cache." NL "Usage: %s [-Dvtrn] -pPATH -lLIMIT" NL " %s [-nti] -dINTERVAL -pPATH -lLIMIT" NL NL "Options:" NL " -d Daemonize and repeat cache cleaning every INTERVAL minutes." NL " This option is mutually exclusive with the -D, -v and -r" NL " options." NL NL " -D Do a dry run and don't delete anything. This option is mutually" NL " exclusive with the -d option." NL NL " -v Be verbose and print statistics. This option is mutually" NL " exclusive with the -d option." NL NL " -r Clean thoroughly. This assumes that the Apache web server is " NL " not running. This option is mutually exclusive with the -d" NL " option and implies -t." NL NL " -n Be nice. This causes slower processing in favour of other" NL " processes." NL NL " -t Delete all empty directories. By default only cache files are" NL " removed, however with some configurations the large number of" NL " directories created may require attention." NL NL " -p Specify PATH as the root directory of the disk cache." NL NL " -l Specify LIMIT as the total disk cache size limit. Attach 'K'" NL " or 'M' to the number for specifying KBytes or MBytes." NL NL " -i Be intelligent and run only when there was a modification of" NL " the disk cache. This option is only possible together with the" NL " -d option." NL, shortname, shortname, shortname ); exit(1); } #undef NL /* * main */ int main(int argc, const char * const argv[]) { apr_off_t max; apr_time_t current, repeat, delay, previous; apr_status_t status; apr_pool_t *pool, *instance; apr_getopt_t *o; apr_finfo_t info; int retries, isdaemon, limit_found, intelligent, dowork; char opt; const char *arg; char *proxypath, *path; interrupted = 0; repeat = 0; isdaemon = 0; dryrun = 0; limit_found = 0; max = 0; verbose = 0; realclean = 0; benice = 0; deldirs = 0; intelligent = 0; previous = 0; /* avoid compiler warning */ proxypath = NULL; if (apr_app_initialize(&argc, &argv, NULL) != APR_SUCCESS) { return 1; } atexit(apr_terminate); if (argc) { shortname = apr_filepath_name_get(argv[0]); } if (apr_pool_create(&pool, NULL) != APR_SUCCESS) { return 1; } apr_pool_abort_set(oom, pool); apr_file_open_stderr(&errfile, pool); apr_signal(SIGINT, setterm); apr_signal(SIGTERM, setterm); apr_getopt_init(&o, pool, argc, argv); while (1) { status = apr_getopt(o, "iDnvrtd:l:L:p:", &opt, &arg); if (status == APR_EOF) { break; } else if (status != APR_SUCCESS) { usage(); } else { switch (opt) { case 'i': if (intelligent) { usage(); } intelligent = 1; break; case 'D': if (dryrun) { usage(); } dryrun = 1; break; case 'n': if (benice) { usage(); } benice = 1; break; case 't': if (deldirs) { usage(); } deldirs = 1; break; case 'v': if (verbose) { usage(); } verbose = 1; break; case 'r': if (realclean) { usage(); } realclean = 1; deldirs = 1; break; case 'd': if (isdaemon) { usage(); } isdaemon = 1; repeat = apr_atoi64(arg); repeat *= SECS_PER_MIN; repeat *= APR_USEC_PER_SEC; break; case 'l': if (limit_found) { usage(); } limit_found = 1; do { apr_status_t rv; char *end; rv = apr_strtoff(&max, arg, &end, 10); if (rv == APR_SUCCESS) { if ((*end == 'K' || *end == 'k') && !end[1]) { max *= KBYTE; } else if ((*end == 'M' || *end == 'm') && !end[1]) { max *= MBYTE; } else if ((*end == 'G' || *end == 'g') && !end[1]) { max *= GBYTE; } else if (*end && /* neither empty nor [Bb] */ ((*end != 'B' && *end != 'b') || end[1])) { rv = APR_EGENERAL; } } if (rv != APR_SUCCESS) { apr_file_printf(errfile, "Invalid limit: %s" APR_EOL_STR APR_EOL_STR, arg); usage(); } } while(0); break; case 'p': if (proxypath) { usage(); } proxypath = apr_pstrdup(pool, arg); if (apr_filepath_set(proxypath, pool) != APR_SUCCESS) { usage(); } break; } /* switch */ } /* else */ } /* while */ if (o->ind != argc) { usage(); } if (isdaemon && (repeat <= 0 || verbose || realclean || dryrun)) { usage(); } if (!isdaemon && intelligent) { usage(); } if (!proxypath || max <= 0) { usage(); } if (apr_filepath_get(&path, 0, pool) != APR_SUCCESS) { usage(); } baselen = strlen(path); #ifndef DEBUG if (isdaemon) { apr_file_close(errfile); apr_proc_detach(APR_PROC_DETACH_DAEMONIZE); } #endif do { apr_pool_create(&instance, pool); now = apr_time_now(); APR_RING_INIT(&root, _entry, link); delcount = 0; unsolicited = 0; dowork = 0; switch (intelligent) { case 0: dowork = 1; break; case 1: retries = STAT_ATTEMPTS; status = APR_SUCCESS; do { if (status != APR_SUCCESS) { apr_sleep(STAT_DELAY); } status = apr_stat(&info, path, APR_FINFO_MTIME, instance); } while (status != APR_SUCCESS && !interrupted && --retries); if (status == APR_SUCCESS) { previous = info.mtime; intelligent = 2; } dowork = 1; break; case 2: retries = STAT_ATTEMPTS; status = APR_SUCCESS; do { if (status != APR_SUCCESS) { apr_sleep(STAT_DELAY); } status = apr_stat(&info, path, APR_FINFO_MTIME, instance); } while (status != APR_SUCCESS && !interrupted && --retries); if (status == APR_SUCCESS) { if (previous != info.mtime) { dowork = 1; } previous = info.mtime; break; } intelligent = 1; dowork = 1; break; } if (dowork && !interrupted) { if (!process_dir(path, instance) && !interrupted) { purge(path, instance, max); } else if (!isdaemon && !interrupted) { apr_file_printf(errfile, "An error occurred, cache cleaning " "aborted." APR_EOL_STR); return 1; } if (intelligent && !interrupted) { retries = STAT_ATTEMPTS; status = APR_SUCCESS; do { if (status != APR_SUCCESS) { apr_sleep(STAT_DELAY); } status = apr_stat(&info, path, APR_FINFO_MTIME, instance); } while (status != APR_SUCCESS && !interrupted && --retries); if (status == APR_SUCCESS) { previous = info.mtime; intelligent = 2; } else { intelligent = 1; } } } apr_pool_destroy(instance); current = apr_time_now(); if (current < now) { delay = repeat; } else if (current - now >= repeat) { delay = repeat; } else { delay = now + repeat - current; } /* we can't sleep the whole delay time here apiece as this is racy * with respect to interrupt delivery - think about what happens * if we have tested for an interrupt, then get scheduled * before the apr_sleep() call and while waiting for the cpu * we do get an interrupt */ if (isdaemon) { while (delay && !interrupted) { if (delay > APR_USEC_PER_SEC) { apr_sleep(APR_USEC_PER_SEC); delay -= APR_USEC_PER_SEC; } else { apr_sleep(delay); delay = 0; } } } } while (isdaemon && !interrupted); if (!isdaemon && interrupted) { apr_file_printf(errfile, "Cache cleaning aborted due to user " "request." APR_EOL_STR); return 1; } return 0; }
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