static void snprintf_int64(CuTest *tc)
{
char buf[100];
apr_int64_t i = APR_INT64_C(-42);
apr_uint64_t ui = APR_INT64_C(42); /* no APR_UINT64_C */
apr_uint64_t big = APR_INT64_C(3141592653589793238);
apr_snprintf(buf, sizeof buf, "%" APR_INT64_T_FMT, i);
CuAssertStrEquals(tc, buf, "-42");
apr_snprintf(buf, sizeof buf, "%" APR_UINT64_T_FMT, ui);
CuAssertStrEquals(tc, buf, "42");
apr_snprintf(buf, sizeof buf, "%" APR_UINT64_T_FMT, big);
CuAssertStrEquals(tc, buf, "3141592653589793238");
}
void log4cxx::helpers::RelativeTimeDateFormat::format(
LogString &s,
log4cxx_time_t date,
Pool& p) const {
log4cxx_int64_t interval = (date - startTime) / APR_INT64_C(1000);
StringHelper::toString(interval, p, s);
}
static void test_insertfile(abts_case *tc, void *ctx)
{
apr_bucket_alloc_t *ba = apr_bucket_alloc_create(p);
apr_bucket_brigade *bb;
const apr_off_t bignum = (APR_INT64_C(2) << 32) + 424242;
apr_off_t count;
apr_file_t *f;
apr_bucket *e;
ABTS_ASSERT(tc, "open test file",
apr_file_open(&f, TIF_FNAME,
APR_FOPEN_WRITE | APR_FOPEN_TRUNCATE
| APR_FOPEN_CREATE | APR_FOPEN_SPARSE,
APR_OS_DEFAULT, p) == APR_SUCCESS);
if (apr_file_trunc(f, bignum)) {
apr_file_close(f);
apr_file_remove(TIF_FNAME, p);
ABTS_NOT_IMPL(tc, "Skipped: could not create large file");
return;
}
bb = apr_brigade_create(p, ba);
e = apr_brigade_insert_file(bb, f, 0, bignum, p);
ABTS_ASSERT(tc, "inserted file was not at end of brigade",
e == APR_BRIGADE_LAST(bb));
/* check that the total size of inserted buckets is equal to the
* total size of the file. */
count = 0;
for (e = APR_BRIGADE_FIRST(bb);
e != APR_BRIGADE_SENTINEL(bb);
e = APR_BUCKET_NEXT(e)) {
ABTS_ASSERT(tc, "bucket size sane", e->length != (apr_size_t)-1);
count += e->length;
}
ABTS_ASSERT(tc, "total size of buckets incorrect", count == bignum);
apr_brigade_destroy(bb);
/* Truncate the file to zero size before close() so that we don't
* actually write out the large file if we are on a non-sparse file
* system - like Mac OS X's HFS. Otherwise, pity the poor user who
* has to wait for the 8GB file to be written to disk.
*/
apr_file_trunc(f, 0);
apr_file_close(f);
apr_bucket_alloc_destroy(ba);
apr_file_remove(TIF_FNAME, p);
}
static void more_int64_fmts(abts_case *tc, void *data)
{
char buf[100];
apr_int64_t i = APR_INT64_C(-42);
apr_int64_t ibig = APR_INT64_C(-314159265358979323);
apr_uint64_t ui = APR_UINT64_C(42);
apr_uint64_t big = APR_UINT64_C(3141592653589793238);
apr_snprintf(buf, sizeof buf, "%" APR_INT64_T_FMT, i);
ABTS_STR_EQUAL(tc, buf, "-42");
apr_snprintf(buf, sizeof buf, "%" APR_UINT64_T_FMT, ui);
ABTS_STR_EQUAL(tc, buf, "42");
apr_snprintf(buf, sizeof buf, "%" APR_UINT64_T_FMT, big);
ABTS_STR_EQUAL(tc, buf, "3141592653589793238");
apr_snprintf(buf, sizeof buf, "%" APR_INT64_T_FMT, ibig);
ABTS_STR_EQUAL(tc, buf, "-314159265358979323");
}
static void string_strtoi64(CuTest *tc)
{
static const struct {
int errnum, base;
const char *in, *end;
apr_int64_t result;
} ts[] = {
/* base 10 tests */
{ 0, 10, "123545", NULL, APR_INT64_C(123545) },
{ 0, 10, " 123545", NULL, APR_INT64_C(123545) },
{ 0, 10, " +123545", NULL, APR_INT64_C(123545) },
{ 0, 10, "-123545", NULL, APR_INT64_C(-123545) },
{ 0, 10, " 00000123545", NULL, APR_INT64_C(123545) },
{ 0, 10, "123545ZZZ", "ZZZ", APR_INT64_C(123545) },
{ 0, 10, " 123545 ", " ", APR_INT64_C(123545) },
/* base 16 tests */
{ 0, 16, "1E299", NULL, APR_INT64_C(123545) },
{ 0, 16, "1e299", NULL, APR_INT64_C(123545) },
{ 0, 16, "0x1e299", NULL, APR_INT64_C(123545) },
{ 0, 16, "0X1E299", NULL, APR_INT64_C(123545) },
{ 0, 16, "+1e299", NULL, APR_INT64_C(123545) },
{ 0, 16, "-1e299", NULL, APR_INT64_C(-123545) },
{ 0, 16, " -1e299", NULL, APR_INT64_C(-123545) },
/* automatic base detection tests */
{ 0, 0, "123545", NULL, APR_INT64_C(123545) },
{ 0, 0, "0x1e299", NULL, APR_INT64_C(123545) },
{ 0, 0, " 0x1e299", NULL, APR_INT64_C(123545) },
{ 0, 0, "+0x1e299", NULL, APR_INT64_C(123545) },
{ 0, 0, "-0x1e299", NULL, APR_INT64_C(-123545) },
/* large number tests */
{ 0, 10, "8589934605", NULL, APR_INT64_C(8589934605) },
{ 0, 10, "-8589934605", NULL, APR_INT64_C(-8589934605) },
{ 0, 16, "0x20000000D", NULL, APR_INT64_C(8589934605) },
{ 0, 16, "-0x20000000D", NULL, APR_INT64_C(-8589934605) },
{ 0, 16, " 0x20000000D", NULL, APR_INT64_C(8589934605) },
{ 0, 16, " 0x20000000D", NULL, APR_INT64_C(8589934605) },
/* error cases */
{ ERANGE, 10, "999999999999999999999999999999999", "", MY_LLONG_MAX },
{ ERANGE, 10, "-999999999999999999999999999999999", "", MY_LLONG_MIN },
#if 0
/* C99 doesn't require EINVAL for an invalid range. */
{ EINVAL, 99, "", (void *)-1 /* don't care */, 0 },
#endif
/* some strtoll implementations give EINVAL when no conversion
* is performed. */
{ -1 /* don't care */, 10, "zzz", "zzz", APR_INT64_C(0) },
{ -1 /* don't care */, 10, "", NULL, APR_INT64_C(0) }
};
int n;
for (n = 0; n < sizeof(ts)/sizeof(ts[0]); n++) {
char *end = "end ptr not changed";
apr_int64_t result;
int errnum;
errno = 0;
result = apr_strtoi64(ts[n].in, &end, ts[n].base);
errnum = errno;
CuAssert(tc,
apr_psprintf(p, "for '%s': result was %" APR_INT64_T_FMT
" not %" APR_INT64_T_FMT, ts[n].in,
result, ts[n].result),
result == ts[n].result);
if (ts[n].errnum != -1) {
CuAssert(tc,
apr_psprintf(p, "for '%s': errno was %d not %d", ts[n].in,
errnum, ts[n].errnum),
ts[n].errnum == errnum);
}
if (ts[n].end == NULL) {
/* end must point to NUL terminator of .in */
CuAssertPtrEquals(tc, ts[n].in + strlen(ts[n].in), end);
} else if (ts[n].end != (void *)-1) {
CuAssert(tc,
apr_psprintf(p, "for '%s', end was '%s' not '%s'",
ts[n].in, end, ts[n].end),
strcmp(ts[n].end, end) == 0);
}
}
}
CACHE_DECLARE(int) ap_cache_check_freshness(cache_handle_t *h,
request_rec *r)
{
apr_int64_t age, maxage_req, maxage_cresp, maxage, smaxage, maxstale;
apr_int64_t minfresh;
const char *cc_cresp, *cc_req;
const char *pragma;
const char *agestr = NULL;
const char *expstr = NULL;
char *val;
apr_time_t age_c = 0;
cache_info *info = &(h->cache_obj->info);
cache_server_conf *conf =
(cache_server_conf *)ap_get_module_config(r->server->module_config,
&cache_module);
/*
* We now want to check if our cached data is still fresh. This depends
* on a few things, in this order:
*
* - RFC2616 14.9.4 End to end reload, Cache-Control: no-cache. no-cache in
* either the request or the cached response means that we must
* revalidate the request unconditionally, overriding any expiration
* mechanism. It's equivalent to max-age=0,must-revalidate.
*
* - RFC2616 14.32 Pragma: no-cache This is treated the same as
* Cache-Control: no-cache.
*
* - RFC2616 14.9.3 Cache-Control: max-stale, must-revalidate,
* proxy-revalidate if the max-stale request header exists, modify the
* stale calculations below so that an object can be at most <max-stale>
* seconds stale before we request a revalidation, _UNLESS_ a
* must-revalidate or proxy-revalidate cached response header exists to
* stop us doing this.
*
* - RFC2616 14.9.3 Cache-Control: s-maxage the origin server specifies the
* maximum age an object can be before it is considered stale. This
* directive has the effect of proxy|must revalidate, which in turn means
* simple ignore any max-stale setting.
*
* - RFC2616 14.9.4 Cache-Control: max-age this header can appear in both
* requests and responses. If both are specified, the smaller of the two
* takes priority.
*
* - RFC2616 14.21 Expires: if this request header exists in the cached
* entity, and it's value is in the past, it has expired.
*
*/
/* This value comes from the client's initial request. */
cc_req = apr_table_get(r->headers_in, "Cache-Control");
pragma = apr_table_get(r->headers_in, "Pragma");
if (ap_cache_liststr(NULL, pragma, "no-cache", NULL)
|| ap_cache_liststr(NULL, cc_req, "no-cache", NULL)) {
if (!conf->ignorecachecontrol) {
/* Treat as stale, causing revalidation */
return 0;
}
ap_log_error(APLOG_MARK, APLOG_INFO, 0, r->server,
"Incoming request is asking for a uncached version of "
"%s, but we know better and are ignoring it",
r->unparsed_uri);
}
/* These come from the cached entity. */
cc_cresp = apr_table_get(h->resp_hdrs, "Cache-Control");
expstr = apr_table_get(h->resp_hdrs, "Expires");
if (ap_cache_liststr(NULL, cc_cresp, "no-cache", NULL)) {
/*
* The cached entity contained Cache-Control: no-cache, so treat as
* stale causing revalidation
*/
return 0;
}
if ((agestr = apr_table_get(h->resp_hdrs, "Age"))) {
age_c = apr_atoi64(agestr);
}
/* calculate age of object */
age = ap_cache_current_age(info, age_c, r->request_time);
/* extract s-maxage */
if (cc_cresp && ap_cache_liststr(r->pool, cc_cresp, "s-maxage", &val)
&& val != NULL) {
smaxage = apr_atoi64(val);
}
else {
smaxage = -1;
}
/* extract max-age from request */
if (!conf->ignorecachecontrol
&& cc_req && ap_cache_liststr(r->pool, cc_req, "max-age", &val)
&& val != NULL) {
maxage_req = apr_atoi64(val);
}
else {
maxage_req = -1;
}
/* extract max-age from response */
if (cc_cresp && ap_cache_liststr(r->pool, cc_cresp, "max-age", &val)
&& val != NULL) {
maxage_cresp = apr_atoi64(val);
}
else {
maxage_cresp = -1;
}
/*
* if both maxage request and response, the smaller one takes priority
*/
if (maxage_req == -1) {
maxage = maxage_cresp;
}
else if (maxage_cresp == -1) {
maxage = maxage_req;
}
else {
maxage = MIN(maxage_req, maxage_cresp);
}
/* extract max-stale */
if (cc_req && ap_cache_liststr(r->pool, cc_req, "max-stale", &val)) {
if(val != NULL) {
maxstale = apr_atoi64(val);
}
else {
/*
* If no value is assigned to max-stale, then the client is willing
* to accept a stale response of any age (RFC2616 14.9.3). We will
* set it to one year in this case as this situation is somewhat
* similar to a "never expires" Expires header (RFC2616 14.21)
* which is set to a date one year from the time the response is
* sent in this case.
*/
maxstale = APR_INT64_C(86400*365);
}
}
else {
maxstale = 0;
}
/* extract min-fresh */
if (!conf->ignorecachecontrol
&& cc_req && ap_cache_liststr(r->pool, cc_req, "min-fresh", &val)
&& val != NULL) {
minfresh = apr_atoi64(val);
}
else {
minfresh = 0;
}
/* override maxstale if must-revalidate or proxy-revalidate */
if (maxstale && ((cc_cresp &&
ap_cache_liststr(NULL, cc_cresp,
"must-revalidate", NULL)) ||
(cc_cresp &&
ap_cache_liststr(NULL, cc_cresp,
"proxy-revalidate", NULL)))) {
maxstale = 0;
}
/* handle expiration */
if (((smaxage != -1) && (age < (smaxage - minfresh))) ||
((maxage != -1) && (age < (maxage + maxstale - minfresh))) ||
((smaxage == -1) && (maxage == -1) &&
(info->expire != APR_DATE_BAD) &&
(age < (apr_time_sec(info->expire - info->date) + maxstale - minfresh)))) {
const char *warn_head;
warn_head = apr_table_get(h->resp_hdrs, "Warning");
/* it's fresh darlings... */
/* set age header on response */
apr_table_set(h->resp_hdrs, "Age",
apr_psprintf(r->pool, "%lu", (unsigned long)age));
/* add warning if maxstale overrode freshness calculation */
if (!(((smaxage != -1) && age < smaxage) ||
((maxage != -1) && age < maxage) ||
(info->expire != APR_DATE_BAD &&
(apr_time_sec(info->expire - info->date)) > age))) {
/* make sure we don't stomp on a previous warning */
if ((warn_head == NULL) ||
((warn_head != NULL) && (ap_strstr_c(warn_head, "110") == NULL))) {
apr_table_merge(h->resp_hdrs, "Warning",
"110 Response is stale");
}
}
/*
* If none of Expires, Cache-Control: max-age, or Cache-Control:
* s-maxage appears in the response, and the respose header age
* calculated is more than 24 hours add the warning 113
*/
if ((maxage_cresp == -1) && (smaxage == -1) &&
(expstr == NULL) && (age > 86400)) {
/* Make sure we don't stomp on a previous warning, and don't dup
* a 113 marning that is already present. Also, make sure to add
* the new warning to the correct *headers_out location.
*/
if ((warn_head == NULL) ||
((warn_head != NULL) && (ap_strstr_c(warn_head, "113") == NULL))) {
apr_table_merge(h->resp_hdrs, "Warning",
"113 Heuristic expiration");
}
}
return 1; /* Cache object is fresh (enough) */
}
return 0; /* Cache object is stale */
}
#include "apr_errno.h"
#include "apr_general.h"
#include "apr_lib.h"
#include "test_apr.h"
#include "apr_strings.h"
#include <time.h>
#define STR_SIZE 45
/* The time value is used throughout the tests, so just make this a global.
* Also, we need a single value that we can test for the positive tests, so
* I chose the number below, it corresponds to:
* 2002-08-14 12:05:36.186711 -25200 [257 Sat].
* Which happens to be when I wrote the new tests.
*/
static apr_time_t now = APR_INT64_C(1032030336186711);
static char* print_time (apr_pool_t *pool, const apr_time_exp_t *xt)
{
return apr_psprintf (pool,
"%04d-%02d-%02d %02d:%02d:%02d.%06d %+05d [%d %s]%s",
xt->tm_year + 1900,
xt->tm_mon,
xt->tm_mday,
xt->tm_hour,
xt->tm_min,
xt->tm_sec,
xt->tm_usec,
xt->tm_gmtoff,
xt->tm_yday + 1,
apr_day_snames[xt->tm_wday],
#include "apr_date.h"
#ifndef srand48
#define srand48 srandom
#endif
#ifndef mrand48
#define mrand48 random
#endif
void gm_timestr_822(char *ts, apr_time_t sec);
void gm_timestr_850(char *ts, apr_time_t sec);
void gm_timestr_ccc(char *ts, apr_time_t sec);
static const apr_time_t year2secs[] = {
APR_INT64_C(0), /* 1970 */
APR_INT64_C(31536000), /* 1971 */
APR_INT64_C(63072000), /* 1972 */
APR_INT64_C(94694400), /* 1973 */
APR_INT64_C(126230400), /* 1974 */
APR_INT64_C(157766400), /* 1975 */
APR_INT64_C(189302400), /* 1976 */
APR_INT64_C(220924800), /* 1977 */
APR_INT64_C(252460800), /* 1978 */
APR_INT64_C(283996800), /* 1979 */
APR_INT64_C(315532800), /* 1980 */
APR_INT64_C(347155200), /* 1981 */
APR_INT64_C(378691200), /* 1982 */
APR_INT64_C(410227200), /* 1983 */
APR_INT64_C(441763200), /* 1984 */
APR_INT64_C(473385600), /* 1985 */
int cache_check_freshness(cache_handle_t *h, cache_request_rec *cache,
request_rec *r)
{
apr_status_t status;
apr_int64_t age, maxage_req, maxage_cresp, maxage, smaxage, maxstale;
apr_int64_t minfresh;
const char *cc_req;
const char *pragma;
const char *agestr = NULL;
apr_time_t age_c = 0;
cache_info *info = &(h->cache_obj->info);
const char *warn_head;
cache_server_conf *conf =
(cache_server_conf *)ap_get_module_config(r->server->module_config,
&cache_module);
/*
* We now want to check if our cached data is still fresh. This depends
* on a few things, in this order:
*
* - RFC2616 14.9.4 End to end reload, Cache-Control: no-cache. no-cache
* in either the request or the cached response means that we must
* perform the request unconditionally, and ignore cached content. We
* should never reach here, but if we do, mark the content as stale,
* as this is the best we can do.
*
* - RFC2616 14.32 Pragma: no-cache This is treated the same as
* Cache-Control: no-cache.
*
* - RFC2616 14.9.3 Cache-Control: max-stale, must-revalidate,
* proxy-revalidate if the max-stale request header exists, modify the
* stale calculations below so that an object can be at most <max-stale>
* seconds stale before we request a revalidation, _UNLESS_ a
* must-revalidate or proxy-revalidate cached response header exists to
* stop us doing this.
*
* - RFC2616 14.9.3 Cache-Control: s-maxage the origin server specifies the
* maximum age an object can be before it is considered stale. This
* directive has the effect of proxy|must revalidate, which in turn means
* simple ignore any max-stale setting.
*
* - RFC2616 14.9.4 Cache-Control: max-age this header can appear in both
* requests and responses. If both are specified, the smaller of the two
* takes priority.
*
* - RFC2616 14.21 Expires: if this request header exists in the cached
* entity, and it's value is in the past, it has expired.
*
*/
/* This value comes from the client's initial request. */
cc_req = apr_table_get(r->headers_in, "Cache-Control");
pragma = apr_table_get(r->headers_in, "Pragma");
ap_cache_control(r, &cache->control_in, cc_req, pragma, r->headers_in);
if (cache->control_in.no_cache) {
if (!conf->ignorecachecontrol) {
/* Treat as stale, causing revalidation */
return 0;
}
ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(00781)
"Incoming request is asking for a uncached version of "
"%s, but we have been configured to ignore it and "
"serve a cached response anyway",
r->unparsed_uri);
}
/* These come from the cached entity. */
if (h->cache_obj->info.control.no_cache
|| h->cache_obj->info.control.invalidated) {
/*
* The cached entity contained Cache-Control: no-cache, or a
* no-cache with a header present, or a private with a header
* present, or the cached entity has been invalidated in the
* past, so treat as stale causing revalidation.
*/
return 0;
}
if ((agestr = apr_table_get(h->resp_hdrs, "Age"))) {
char *endp;
apr_off_t offt;
if (!apr_strtoff(&offt, agestr, &endp, 10)
&& endp > agestr && !*endp) {
age_c = offt;
}
}
/* calculate age of object */
age = ap_cache_current_age(info, age_c, r->request_time);
/* extract s-maxage */
smaxage = h->cache_obj->info.control.s_maxage_value;
/* extract max-age from request */
maxage_req = -1;
if (!conf->ignorecachecontrol) {
maxage_req = cache->control_in.max_age_value;
}
/*
* extract max-age from response, if both s-maxage and max-age, s-maxage
* takes priority
*/
if (smaxage != -1) {
maxage_cresp = smaxage;
}
else {
maxage_cresp = h->cache_obj->info.control.max_age_value;
}
/*
* if both maxage request and response, the smaller one takes priority
*/
if (maxage_req == -1) {
maxage = maxage_cresp;
}
else if (maxage_cresp == -1) {
maxage = maxage_req;
}
else {
maxage = MIN(maxage_req, maxage_cresp);
}
/* extract max-stale */
if (cache->control_in.max_stale) {
if(cache->control_in.max_stale_value != -1) {
maxstale = cache->control_in.max_stale_value;
}
else {
/*
* If no value is assigned to max-stale, then the client is willing
* to accept a stale response of any age (RFC2616 14.9.3). We will
* set it to one year in this case as this situation is somewhat
* similar to a "never expires" Expires header (RFC2616 14.21)
* which is set to a date one year from the time the response is
* sent in this case.
*/
maxstale = APR_INT64_C(86400*365);
}
}
else {
maxstale = 0;
}
/* extract min-fresh */
if (!conf->ignorecachecontrol && cache->control_in.min_fresh) {
minfresh = cache->control_in.min_fresh_value;
}
else {
minfresh = 0;
}
/* override maxstale if must-revalidate, proxy-revalidate or s-maxage */
if (maxstale && (h->cache_obj->info.control.must_revalidate
|| h->cache_obj->info.control.proxy_revalidate || smaxage != -1)) {
maxstale = 0;
}
/* handle expiration */
if (((maxage != -1) && (age < (maxage + maxstale - minfresh))) ||
((smaxage == -1) && (maxage == -1) &&
(info->expire != APR_DATE_BAD) &&
(age < (apr_time_sec(info->expire - info->date) + maxstale - minfresh)))) {
warn_head = apr_table_get(h->resp_hdrs, "Warning");
/* it's fresh darlings... */
/* set age header on response */
apr_table_set(h->resp_hdrs, "Age",
apr_psprintf(r->pool, "%lu", (unsigned long)age));
/* add warning if maxstale overrode freshness calculation */
if (!(((maxage != -1) && age < maxage) ||
(info->expire != APR_DATE_BAD &&
(apr_time_sec(info->expire - info->date)) > age))) {
/* make sure we don't stomp on a previous warning */
if ((warn_head == NULL) ||
((warn_head != NULL) && (ap_strstr_c(warn_head, "110") == NULL))) {
apr_table_mergen(h->resp_hdrs, "Warning",
"110 Response is stale");
}
}
/*
* If none of Expires, Cache-Control: max-age, or Cache-Control:
* s-maxage appears in the response, and the response header age
* calculated is more than 24 hours add the warning 113
*/
if ((maxage_cresp == -1) && (smaxage == -1) && (apr_table_get(
h->resp_hdrs, "Expires") == NULL) && (age > 86400)) {
/* Make sure we don't stomp on a previous warning, and don't dup
* a 113 marning that is already present. Also, make sure to add
* the new warning to the correct *headers_out location.
*/
if ((warn_head == NULL) ||
((warn_head != NULL) && (ap_strstr_c(warn_head, "113") == NULL))) {
apr_table_mergen(h->resp_hdrs, "Warning",
"113 Heuristic expiration");
}
}
return 1; /* Cache object is fresh (enough) */
}
/*
* At this point we are stale, but: if we are under load, we may let
* a significant number of stale requests through before the first
* stale request successfully revalidates itself, causing a sudden
* unexpected thundering herd which in turn brings angst and drama.
*
* So.
*
* We want the first stale request to go through as normal. But the
* second and subsequent request, we must pretend to be fresh until
* the first request comes back with either new content or confirmation
* that the stale content is still fresh.
*
* To achieve this, we create a very simple file based lock based on
* the key of the cached object. We attempt to open the lock file with
* exclusive write access. If we succeed, woohoo! we're first, and we
* follow the stale path to the backend server. If we fail, oh well,
* we follow the fresh path, and avoid being a thundering herd.
*
* The lock lives only as long as the stale request that went on ahead.
* If the request succeeds, the lock is deleted. If the request fails,
* the lock is deleted, and another request gets to make a new lock
* and try again.
*
* At any time, a request marked "no-cache" will force a refresh,
* ignoring the lock, ensuring an extended lockout is impossible.
*
* A lock that exceeds a maximum age will be deleted, and another
* request gets to make a new lock and try again.
*/
status = cache_try_lock(conf, cache, r);
if (APR_SUCCESS == status) {
/* we obtained a lock, follow the stale path */
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00782)
"Cache lock obtained for stale cached URL, "
"revalidating entry: %s",
r->unparsed_uri);
return 0;
}
else if (APR_STATUS_IS_EEXIST(status)) {
/* lock already exists, return stale data anyway, with a warning */
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, status, r, APLOGNO(00783)
"Cache already locked for stale cached URL, "
"pretend it is fresh: %s",
r->unparsed_uri);
/* make sure we don't stomp on a previous warning */
warn_head = apr_table_get(h->resp_hdrs, "Warning");
if ((warn_head == NULL) ||
((warn_head != NULL) && (ap_strstr_c(warn_head, "110") == NULL))) {
apr_table_mergen(h->resp_hdrs, "Warning",
"110 Response is stale");
}
return 1;
}
else {
/* some other error occurred, just treat the object as stale */
ap_log_rerror(APLOG_MARK, APLOG_DEBUG, status, r, APLOGNO(00784)
"Attempt to obtain a cache lock for stale "
"cached URL failed, revalidating entry anyway: %s",
r->unparsed_uri);
return 0;
}
}
