* debuginfod/debuginfod-client.c:
- add debuginfod_config_cache for reading and writing to cache
configuration files, make use of the function within
debuginfod_clean_cache and debuginfod_query_server.
- in debuginfod_query_server, create 000-permission file on failed
queries. Before querying each BUILDID, if corresponding 000 file
detected, compare its stat mtime with parameter from
.cache/cache_miss_s. if mtime is fresher, then return ENOENT and
exit; otherwise unlink the 000 file and proceed to a new query.
* tests/run-debuginfod-find.sh:
- added corresponding tests: test if the 000 file is created on failed
query; if querying the same failed BUILDID, whether the query should
proceed without going through server; set the cache_miss_s to 0 and
query the same buildid, and this time should go through the server.
Signed-off-by: Alice Zhang <[email protected]>
---
ChangeLog | 4 ++
NEWS | 9 +++
debuginfod/debuginfod-client.c | 117 ++++++++++++++++++++++-----------
tests/run-debuginfod-find.sh | 37 +++++++++++
4 files changed, 129 insertions(+), 38 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index e18746fb..3c6f5cc0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2021-04-28 Alice Zhang <[email protected]>
+ * debuginfod/debuginfod-client.c: Make client able to cache negative
+ results.
+ * tests/run-debuginfod-find.sh: Added tests for the feature.
2021-03-30 Frank Ch. Eigler <[email protected]>
* configure.ac: Look for pthread_setname_np.
diff --git a/NEWS b/NEWS
index 038c6019..6d652696 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,15 @@ Version 0.184
debuginfod: Use libarchive's bsdtar as the .deb-family file unpacker.
+debuginfod-client: Now client would cache negative results. When a
+ query fails with 404, a 000-permission file is
+ created. When query for a buildid, check whether
+ such 000-permission file exists in the cache. If
+ so, check its mtime: if mtime is older than the
+ parameter from .cache/cache_miss_s, unlink the
+ 000 file and proceed to a new query; otherwise
+ return an -ENOENT.
+
Version 0.183
debuginfod: New thread-busy metric and more detailed error metrics.
diff --git a/debuginfod/debuginfod-client.c b/debuginfod/debuginfod-client.c
index d5e7bbdf..934ab40a 100644
--- a/debuginfod/debuginfod-client.c
+++ b/debuginfod/debuginfod-client.c
@@ -131,6 +131,11 @@ struct debuginfod_client
static const char *cache_clean_interval_filename = "cache_clean_interval_s";
static const time_t cache_clean_default_interval_s = 86400; /* 1 day */
+/* The cache_miss_default_s within the debuginfod cache specifies how
frequently
+ should the 000-permision file should be released.*/
+static const time_t cache_miss_default_s = 600; /* 10 min */
+static const char *cache_miss_filename = "cache_miss_s";
+
/* The cache_max_unused_age_s file within the debuginfod cache specifies the
the maximum time since last access that a file will remain in the cache. */
static const char *cache_max_unused_age_filename = "max_unused_age_s";
@@ -206,6 +211,38 @@ debuginfod_write_callback (char *ptr, size_t size, size_t
nmemb, void *data)
return (size_t) write(d->fd, (void*)ptr, count);
}
+/* handle config file read and write */
+static int
+debuginfod_config_cache(char *config_path,
+ long cache_config_default_s)
+{
+ int fd;
+ struct stat st;
+ /* if the config file doesn't exist, create one with DEFFILEMODE*/
+ if(stat(config_path, &st) == -1)
+ {
+ fd = open(config_path, O_CREAT | O_RDWR, DEFFILEMODE);
+ if (fd < 0)
+ return -errno;
+
+ if (dprintf(fd, "%ld", cache_config_default_s) < 0)
+ return -errno;
+ }
+
+ long cache_config;
+ FILE *config_file = fopen(config_path, "r");
+ if (config_file)
+ {
+ if (fscanf(config_file, "%ld", &cache_config) != 1)
+ cache_config = cache_config_default_s;
+ fclose(config_file);
+ }
+ else
+ cache_config = cache_config_default_s;
+
+ return cache_config;
+}
+
/* Create the cache and interval file if they do not already exist.
Return 0 if cache and config file are initialized, otherwise return
the appropriate error code. */
@@ -251,52 +288,27 @@ debuginfod_clean_cache(debuginfod_client *c,
char *cache_path, char *interval_path,
char *max_unused_path)
{
+ time_t clean_interval, max_unused_age;
+ int rc = -1;
struct stat st;
- FILE *interval_file;
- FILE *max_unused_file;
- if (stat(interval_path, &st) == -1)
- {
- /* Create new interval file. */
- interval_file = fopen(interval_path, "w");
-
- if (interval_file == NULL)
- return -errno;
-
- int rc = fprintf(interval_file, "%ld", cache_clean_default_interval_s);
- fclose(interval_file);
-
- if (rc < 0)
- return -errno;
- }
+ /* Create new interval file. */
+ rc = debuginfod_config_cache(interval_path, cache_clean_default_interval_s);
+ if (rc < 0)
+ return rc;
+ clean_interval = (time_t)rc;
/* Check timestamp of interval file to see whether cleaning is necessary. */
- time_t clean_interval;
- interval_file = fopen(interval_path, "r");
- if (interval_file)
- {
- if (fscanf(interval_file, "%ld", &clean_interval) != 1)
- clean_interval = cache_clean_default_interval_s;
- fclose(interval_file);
- }
- else
- clean_interval = cache_clean_default_interval_s;
-
+ stat(interval_path, &st);
if (time(NULL) - st.st_mtime < clean_interval)
/* Interval has not passed, skip cleaning. */
return 0;
/* Read max unused age value from config file. */
- time_t max_unused_age;
- max_unused_file = fopen(max_unused_path, "r");
- if (max_unused_file)
- {
- if (fscanf(max_unused_file, "%ld", &max_unused_age) != 1)
- max_unused_age = cache_default_max_unused_age_s;
- fclose(max_unused_file);
- }
- else
- max_unused_age = cache_default_max_unused_age_s;
+ rc = debuginfod_config_cache(max_unused_path,
cache_default_max_unused_age_s);
+ if (rc < 0)
+ return rc;
+ max_unused_age = (time_t)rc;
char * const dirs[] = { cache_path, NULL, };
@@ -500,6 +512,7 @@ debuginfod_query_server (debuginfod_client *c,
char *cache_path = NULL;
char *maxage_path = NULL;
char *interval_path = NULL;
+ char *cache_miss_path = NULL;
char *target_cache_dir = NULL;
char *target_cache_path = NULL;
char *target_cache_tmppath = NULL;
@@ -667,6 +680,7 @@ debuginfod_query_server (debuginfod_client *c,
/* XXX combine these */
xalloc_str (interval_path, "%s/%s", cache_path,
cache_clean_interval_filename);
+ xalloc_str (cache_miss_path, "%s/%s", cache_path, cache_miss_filename);
xalloc_str (maxage_path, "%s/%s", cache_path, cache_max_unused_age_filename);
if (vfd >= 0)
@@ -690,6 +704,24 @@ debuginfod_query_server (debuginfod_client *c,
goto out;
}
+ struct stat st;
+ time_t cache_miss;
+ if (stat(target_cache_path, &st) == 0)
+ {
+ rc = debuginfod_config_cache(cache_miss_path, cache_miss_default_s);
+ if (rc < 0)
+ goto out;
+
+ cache_miss = (time_t)rc;
+ if (time(NULL) - st.st_mtime <= cache_miss)
+ {
+ rc = -ENOENT;
+ goto out;
+ }
+ else
+ unlink(target_cache_path);
+ }
+
long timeout = default_timeout;
const char* timeout_envvar = getenv(server_timeout_envvar);
if (timeout_envvar != NULL)
@@ -708,7 +740,6 @@ debuginfod_query_server (debuginfod_client *c,
/* thereafter, goto out0 on error*/
/* create target directory in cache if not found. */
- struct stat st;
if (stat(target_cache_dir, &st) == -1 && mkdir(target_cache_dir, 0700) < 0)
{
rc = -errno;
@@ -1032,6 +1063,15 @@ debuginfod_query_server (debuginfod_client *c,
}
} while (num_msg > 0);
+ /* create a 000-permission file named as $HOME/.cache
+ * if the query fails with ENOENT.*/
+ if (rc == -ENOENT)
+ {
+ int efd = open (target_cache_path, O_CREAT|O_TRUNC, 0000);
+ if (efd >= 0)
+ close(efd);
+ }
+
if (verified_handle == NULL)
goto out1;
@@ -1113,6 +1153,7 @@ debuginfod_query_server (debuginfod_client *c,
free (cache_path);
free (maxage_path);
free (interval_path);
+ free (cache_miss_path);
free (target_cache_dir);
free (target_cache_path);
free (target_cache_tmppath);
diff --git a/tests/run-debuginfod-find.sh b/tests/run-debuginfod-find.sh
index 8213c8a4..0bdb44d1 100755
--- a/tests/run-debuginfod-find.sh
+++ b/tests/run-debuginfod-find.sh
@@ -152,6 +152,41 @@ testrun ${abs_builddir}/debuginfod_build_id_find -e F/prog
1
########################################################################
+# PR25628
+rm -rf $DEBUGINFOD_CACHE_PATH # clean it from previous tests
+
+# The query is designed to fail, while the 000-permission file should be
created.
+testrun ${abs_top_builddir}/debuginfod/debuginfod-find debuginfo 01234567 ||
true
+if [ ! -f $DEBUGINFOD_CACHE_PATH/01234567/debuginfo ]; then
+ echo "could not find cache in $DEBUGINFOD_CACHE_PATH"
+ exit 1
+fi
+
+if [ -r $DEBUGINFOD_CACHE_PATH/01234567/debuginfo ]; then
+ echo "The cache $DEBUGINFOD_CACHE_PATH/01234567/debuginfo is readable"
+ exit 1
+fi
+
+bytecount_before=`curl -s http://127.0.0.1:$PORT1/metrics | grep
'http_responses_transfer_bytes_count{code="404"}'`
+testrun ${abs_top_builddir}/debuginfod/debuginfod-find debuginfo 01234567 ||
true
+bytecount_after=`curl -s http://127.0.0.1:$PORT1/metrics | grep
'http_responses_transfer_bytes_count{code="404"}'`
+if [ "$bytecount_before" != "$bytecount_after" ]; then
+ echo "http_responses_transfer_bytes_count{code="404"} has changed."
+ exit 1
+fi
+
+# set cache_miss_s to 0 and sleep 1 to make the mtime expire.
+echo 0 > $DEBUGINFOD_CACHE_PATH/cache_miss_s
+sleep 1
+bytecount_before=`curl -s http://127.0.0.1:$PORT1/metrics | grep
'http_responses_transfer_bytes_count{code="404"}'`
+testrun ${abs_top_builddir}/debuginfod/debuginfod-find debuginfo 01234567 ||
true
+bytecount_after=`curl -s http://127.0.0.1:$PORT1/metrics | grep
'http_responses_transfer_bytes_count{code="404"}'`
+if [ "$bytecount_before" == "$bytecount_after" ]; then
+ echo "http_responses_transfer_bytes_count{code="404"} should be incremented."
+ exit 1
+fi
+########################################################################
+
# Test whether debuginfod-find is able to fetch those files.
rm -rf $DEBUGINFOD_CACHE_PATH # clean it from previous tests
filename=`testrun ${abs_top_builddir}/debuginfod/debuginfod-find debuginfo
$BUILDID`
@@ -459,6 +494,7 @@ file -L L/foo
export DEBUGINFOD_URLS=http://127.0.0.1:$PORT1
rm -rf $DEBUGINFOD_CACHE_PATH
testrun ${abs_top_builddir}/debuginfod/debuginfod-find debuginfo $BUILDID &&
false || true
+rm -f $DEBUGINFOD_CACHE_PATH/$BUILDID/debuginfo # drop 000-perm negative-hit
file
export DEBUGINFOD_URLS=http://127.0.0.1:$PORT2
testrun ${abs_top_builddir}/debuginfod/debuginfod-find debuginfo $BUILDID
@@ -466,6 +502,7 @@ testrun ${abs_top_builddir}/debuginfod/debuginfod-find
debuginfo $BUILDID
export DEBUGINFOD_URLS=127.0.0.1:$PORT1
rm -rf $DEBUGINFOD_CACHE_PATH
testrun ${abs_top_builddir}/debuginfod/debuginfod-find debuginfo $BUILDID &&
false || true
+rm -f $DEBUGINFOD_CACHE_PATH/$BUILDID/debuginfo # drop 000-perm negative-hit
file
export DEBUGINFOD_URLS=127.0.0.1:$PORT2
testrun ${abs_top_builddir}/debuginfod/debuginfod-find debuginfo $BUILDID
--
2.30.2
