Finally returning to this .. rebased and updated per feedback.
I'm not sure of a good place to put test cases for this..
>From 13e8c8b96d1a5313fd3edde515a5278cf8c6b23e Mon Sep 17 00:00:00 2001
From: Justin Pryzby <pryz...@telsasoft.com>
Date: Mon, 13 Dec 2021 08:42:38 -0600
Subject: [PATCH v5 1/3] warn when setting GUC to a nonextant library
---
src/backend/utils/misc/guc.c | 106 +++++++++++++++++-
.../unsafe_tests/expected/rolenames.out | 19 ++++
.../modules/unsafe_tests/sql/rolenames.sql | 13 +++
.../worker_spi/expected/worker_spi.out | 2 +
.../modules/worker_spi/sql/worker_spi.sql | 2 +
src/test/regress/expected/rules.out | 8 ++
6 files changed, 147 insertions(+), 3 deletions(-)
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index af4a1c30689..4e38e73a277 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -176,6 +176,12 @@ static bool call_enum_check_hook(struct config_enum *conf, int *newval,
void **extra, GucSource source, int elevel);
static bool check_log_destination(char **newval, void **extra, GucSource source);
+static bool check_local_preload_libraries(char **newval, void **extra,
+ GucSource source);
+static bool check_session_preload_libraries(char **newval, void **extra,
+ GucSource source);
+static bool check_shared_preload_libraries(char **newval, void **extra,
+ GucSource source);
static void assign_log_destination(const char *newval, void *extra);
static bool check_wal_consistency_checking(char **newval, void **extra,
@@ -4272,7 +4278,7 @@ static struct config_string ConfigureNamesString[] =
},
&session_preload_libraries_string,
"",
- NULL, NULL, NULL
+ check_session_preload_libraries, NULL, NULL
},
{
@@ -4283,7 +4289,7 @@ static struct config_string ConfigureNamesString[] =
},
&shared_preload_libraries_string,
"",
- NULL, NULL, NULL
+ check_shared_preload_libraries, NULL, NULL
},
{
@@ -4294,7 +4300,7 @@ static struct config_string ConfigureNamesString[] =
},
&local_preload_libraries_string,
"",
- NULL, NULL, NULL
+ check_local_preload_libraries, NULL, NULL
},
{
@@ -12506,6 +12512,100 @@ check_max_worker_processes(int *newval, void **extra, GucSource source)
return true;
}
+/*
+ * See also load_libraries() and internal_load_library().
+ */
+static bool
+check_preload_libraries(char **newval, void **extra, GucSource source,
+ bool restricted)
+{
+ char *rawstring;
+ List *elemlist;
+ ListCell *l;
+
+ /* nothing to do if empty */
+ if (newval == NULL || *newval[0] == '\0')
+ return true;
+
+ /*
+ * issue warnings only during an interactive SET, from ALTER
+ * ROLE/DATABASE/SYSTEM.
+ */
+ if (source != PGC_S_TEST && source != PGC_S_FILE)
+ return true;
+
+ /* Need a modifiable copy of string */
+ rawstring = pstrdup(*newval);
+
+ /* Parse string into list of filename paths */
+ if (!SplitDirectoriesString(rawstring, ',', &elemlist))
+ {
+ /* Should not happen ? */
+ return false;
+ }
+
+ foreach(l, elemlist)
+ {
+ /* Note that filename was already canonicalized */
+ char *filename = (char *) lfirst(l);
+ char *expanded = NULL;
+
+ /* If restricting, insert $libdir/plugins if not mentioned already */
+ if (restricted && first_dir_separator(filename) == NULL)
+ {
+ expanded = psprintf("$libdir/plugins/%s", filename);
+ filename = expanded;
+ }
+
+ /*
+ * stat()/access() only check that the library exists, not that it has
+ * the correct magic number or even a library. But error messages from
+ * dlopen() are not portable, so it'd be hard to report any problem
+ * other than "does not exist".
+ */
+ if (access(filename, R_OK) == 0)
+ continue;
+
+
+ if (source == PGC_S_FILE)
+ /* ALTER SYSTEM */
+ ereport(WARNING,
+ errcode_for_file_access(),
+ errmsg("could not access file \"%s\"", filename),
+ errdetail("The server will currently fail to start with this setting."),
+ errhint("If the server is shut down, it will be necessary to manually edit the %s file to allow it to start again.",
+ "postgresql.auto.conf"));
+ else
+ /* ALTER ROLE/DATABASE */
+ ereport(WARNING,
+ errcode_for_file_access(),
+ errmsg("could not access file \"%s\"", filename),
+ errdetail("New sessions will currently fail to connect with the new setting."));
+ }
+
+ list_free_deep(elemlist);
+ pfree(rawstring);
+ return true;
+}
+
+static bool
+check_shared_preload_libraries(char **newval, void **extra, GucSource source)
+{
+ return check_preload_libraries(newval, extra, source, true);
+}
+
+static bool
+check_local_preload_libraries(char **newval, void **extra, GucSource source)
+{
+ return check_preload_libraries(newval, extra, source, false);
+}
+
+static bool
+check_session_preload_libraries(char **newval, void **extra, GucSource source)
+{
+ return check_preload_libraries(newval, extra, source, true);
+}
+
static bool
check_effective_io_concurrency(int *newval, void **extra, GucSource source)
{
diff --git a/src/test/modules/unsafe_tests/expected/rolenames.out b/src/test/modules/unsafe_tests/expected/rolenames.out
index 88b1ff843be..ac161ce7c33 100644
--- a/src/test/modules/unsafe_tests/expected/rolenames.out
+++ b/src/test/modules/unsafe_tests/expected/rolenames.out
@@ -1082,6 +1082,25 @@ RESET SESSION AUTHORIZATION;
ERROR: current transaction is aborted, commands ignored until end of transaction block
ROLLBACK;
REVOKE pg_read_all_settings FROM regress_role_haspriv;
+-- test some warnings
+ALTER ROLE regress_testrol0 SET session_preload_libraries="DoesNotExist";
+WARNING: could not access file "$libdir/plugins/DoesNotExist"
+DETAIL: New sessions will currently fail to connect with the new setting.
+ALTER ROLE regress_testrol0 SET local_preload_libraries="DoesNotExist";
+WARNING: could not access file "DoesNotExist"
+DETAIL: New sessions will currently fail to connect with the new setting.
+CREATE DATABASE regress_nosuch_db;
+ALTER DATABASE regress_nosuch_db SET session_preload_libraries="DoesNotExist";
+WARNING: could not access file "$libdir/plugins/DoesNotExist"
+DETAIL: New sessions will currently fail to connect with the new setting.
+ALTER DATABASE regress_nosuch_db SET local_preload_libraries="DoesNotExist";
+WARNING: could not access file "DoesNotExist"
+DETAIL: New sessions will currently fail to connect with the new setting.
+DROP DATABASE regress_nosuch_db;
+-- SET doesn't do anything, but should not warn, either
+SET session_preload_libraries="DoesNotExist";
+SET SESSION session_preload_libraries="DoesNotExist";
+begin; SET LOCAL session_preload_libraries="DoesNotExist"; rollback;
-- clean up
\c
DROP SCHEMA test_roles_schema;
diff --git a/src/test/modules/unsafe_tests/sql/rolenames.sql b/src/test/modules/unsafe_tests/sql/rolenames.sql
index adac36536db..cf605b08d30 100644
--- a/src/test/modules/unsafe_tests/sql/rolenames.sql
+++ b/src/test/modules/unsafe_tests/sql/rolenames.sql
@@ -494,6 +494,19 @@ RESET SESSION AUTHORIZATION;
ROLLBACK;
REVOKE pg_read_all_settings FROM regress_role_haspriv;
+-- test some warnings
+ALTER ROLE regress_testrol0 SET session_preload_libraries="DoesNotExist";
+ALTER ROLE regress_testrol0 SET local_preload_libraries="DoesNotExist";
+CREATE DATABASE regress_nosuch_db;
+ALTER DATABASE regress_nosuch_db SET session_preload_libraries="DoesNotExist";
+ALTER DATABASE regress_nosuch_db SET local_preload_libraries="DoesNotExist";
+DROP DATABASE regress_nosuch_db;
+
+-- SET doesn't do anything, but should not warn, either
+SET session_preload_libraries="DoesNotExist";
+SET SESSION session_preload_libraries="DoesNotExist";
+begin; SET LOCAL session_preload_libraries="DoesNotExist"; rollback;
+
-- clean up
\c
diff --git a/src/test/modules/worker_spi/expected/worker_spi.out b/src/test/modules/worker_spi/expected/worker_spi.out
index dc0a79bf759..5b275669bcf 100644
--- a/src/test/modules/worker_spi/expected/worker_spi.out
+++ b/src/test/modules/worker_spi/expected/worker_spi.out
@@ -28,6 +28,8 @@ SELECT pg_reload_conf();
t
(1 row)
+-- reconnect to avoid unstable test result due to asynchronous signal
+\c
-- wait until the worker has processed the tuple we just inserted
DO $$
DECLARE
diff --git a/src/test/modules/worker_spi/sql/worker_spi.sql b/src/test/modules/worker_spi/sql/worker_spi.sql
index 4683523b29d..4ed5370d456 100644
--- a/src/test/modules/worker_spi/sql/worker_spi.sql
+++ b/src/test/modules/worker_spi/sql/worker_spi.sql
@@ -18,6 +18,8 @@ END
$$;
INSERT INTO schema4.counted VALUES ('total', 0), ('delta', 1);
SELECT pg_reload_conf();
+-- reconnect to avoid unstable test result due to asynchronous signal
+\c
-- wait until the worker has processed the tuple we just inserted
DO $$
DECLARE
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 7ec3d2688f0..ea4f9eb39e2 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -3392,6 +3392,14 @@ CREATE FUNCTION func_with_set_params() RETURNS integer
SET datestyle to iso, mdy
SET local_preload_libraries TO "Mixed/Case", 'c:/''a"/path', '', '0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789'
IMMUTABLE STRICT;
+WARNING: could not access file "Mixed/Case"
+DETAIL: New sessions will currently fail to connect with the new setting.
+WARNING: could not access file "c:/'a"/path"
+DETAIL: New sessions will currently fail to connect with the new setting.
+WARNING: could not access file ""
+DETAIL: New sessions will currently fail to connect with the new setting.
+WARNING: could not access file "0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789"
+DETAIL: New sessions will currently fail to connect with the new setting.
SELECT pg_get_functiondef('func_with_set_params()'::regprocedure);
pg_get_functiondef
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------
--
2.17.1
>From c08b511a3f76dc423b71a2c2584696b2d41afc63 Mon Sep 17 00:00:00 2001
From: Justin Pryzby <pryz...@telsasoft.com>
Date: Sat, 18 Dec 2021 22:51:01 -0600
Subject: [PATCH v5 2/3] errcontext if server fails to start due to library
GUCs
---
src/backend/utils/fmgr/dfmgr.c | 20 +++++++++++++++-----
src/backend/utils/init/miscinit.c | 2 +-
src/include/fmgr.h | 1 +
3 files changed, 17 insertions(+), 6 deletions(-)
diff --git a/src/backend/utils/fmgr/dfmgr.c b/src/backend/utils/fmgr/dfmgr.c
index 7f9ea972804..081d75fd724 100644
--- a/src/backend/utils/fmgr/dfmgr.c
+++ b/src/backend/utils/fmgr/dfmgr.c
@@ -75,7 +75,7 @@ static DynamicFileList *file_tail = NULL;
char *Dynamic_library_path;
-static void *internal_load_library(const char *libname);
+static void *internal_load_library(const char *libname, const char *gucname);
static void incompatible_module_error(const char *libname,
const Pg_magic_struct *module_magic_data) pg_attribute_noreturn();
static bool file_exists(const char *name);
@@ -113,7 +113,7 @@ load_external_function(const char *filename, const char *funcname,
fullname = expand_dynamic_library_name(filename);
/* Load the shared library, unless we already did */
- lib_handle = internal_load_library(fullname);
+ lib_handle = internal_load_library(fullname, NULL);
/* Return handle if caller wants it */
if (filehandle)
@@ -142,6 +142,14 @@ load_external_function(const char *filename, const char *funcname,
*/
void
load_file(const char *filename, bool restricted)
+{
+ load_file_guc(filename, restricted, NULL);
+}
+
+/*
+ * Also accepts a GUC arg, for error reports
+ */
+void load_file_guc(const char *filename, bool restricted, const char *gucname)
{
char *fullname;
@@ -153,7 +161,7 @@ load_file(const char *filename, bool restricted)
fullname = expand_dynamic_library_name(filename);
/* Load the shared library */
- (void) internal_load_library(fullname);
+ (void) internal_load_library(fullname, gucname);
pfree(fullname);
}
@@ -172,6 +180,7 @@ lookup_external_function(void *filehandle, const char *funcname)
/*
* Load the specified dynamic-link library file, unless it already is
* loaded. Return the pg_dl* handle for the file.
+ * gucname may be passed for error reports.
*
* Note: libname is expected to be an exact name for the library file.
*
@@ -181,7 +190,7 @@ lookup_external_function(void *filehandle, const char *funcname)
* perhaps other things that are definitely unsafe currently.
*/
static void *
-internal_load_library(const char *libname)
+internal_load_library(const char *libname, const char *gucname)
{
DynamicFileList *file_scanner;
PGModuleMagicFunction magic_func;
@@ -206,6 +215,7 @@ internal_load_library(const char *libname)
if (stat(libname, &stat_buf) == -1)
ereport(ERROR,
(errcode_for_file_access(),
+ gucname ? errcontext("while loading shared libraries for setting \"%s\"", gucname) : 0,
errmsg("could not access file \"%s\": %m",
libname)));
@@ -694,7 +704,7 @@ RestoreLibraryState(char *start_address)
{
while (*start_address != '\0')
{
- internal_load_library(start_address);
+ internal_load_library(start_address, NULL);
start_address += strlen(start_address) + 1;
}
}
diff --git a/src/backend/utils/init/miscinit.c b/src/backend/utils/init/miscinit.c
index eb43b2c5e57..4237677c222 100644
--- a/src/backend/utils/init/miscinit.c
+++ b/src/backend/utils/init/miscinit.c
@@ -1664,7 +1664,7 @@ load_libraries(const char *libraries, const char *gucname, bool restricted)
expanded = psprintf("$libdir/plugins/%s", filename);
filename = expanded;
}
- load_file(filename, restricted);
+ load_file_guc(filename, restricted, gucname);
ereport(DEBUG1,
(errmsg_internal("loaded library \"%s\"", filename)));
if (expanded)
diff --git a/src/include/fmgr.h b/src/include/fmgr.h
index 380a82b9de3..3af652cdf99 100644
--- a/src/include/fmgr.h
+++ b/src/include/fmgr.h
@@ -737,6 +737,7 @@ extern void *load_external_function(const char *filename, const char *funcname,
bool signalNotFound, void **filehandle);
extern void *lookup_external_function(void *filehandle, const char *funcname);
extern void load_file(const char *filename, bool restricted);
+extern void load_file_guc(const char *filename, bool restricted, const char *gucname);
extern void **find_rendezvous_variable(const char *varName);
extern Size EstimateLibraryStateSpace(void);
extern void SerializeLibraryState(Size maxsize, char *start_address);
--
2.17.1
>From 62f43d2731e4aa782ebd6503266f596103538a48 Mon Sep 17 00:00:00 2001
From: Justin Pryzby <pryz...@telsasoft.com>
Date: Wed, 2 Feb 2022 20:54:49 -0600
Subject: [PATCH v5 3/3] show the GUC source in errcontext
---
src/backend/utils/fmgr/dfmgr.c | 13 ++++++++++---
src/backend/utils/misc/guc.c | 24 ++++++++++++++++++++++++
src/include/utils/guc.h | 1 +
3 files changed, 35 insertions(+), 3 deletions(-)
diff --git a/src/backend/utils/fmgr/dfmgr.c b/src/backend/utils/fmgr/dfmgr.c
index 081d75fd724..9ccb12637a0 100644
--- a/src/backend/utils/fmgr/dfmgr.c
+++ b/src/backend/utils/fmgr/dfmgr.c
@@ -34,6 +34,7 @@
#include "lib/stringinfo.h"
#include "miscadmin.h"
#include "storage/shmem.h"
+#include "utils/guc_tables.h"
#include "utils/hsearch.h"
@@ -213,11 +214,17 @@ internal_load_library(const char *libname, const char *gucname)
* Check for same files - different paths (ie, symlink or link)
*/
if (stat(libname, &stat_buf) == -1)
+ {
+ char *errstr = strerror(errno);
+ int linenum;
+ char *sourcefile = gucname ? GetConfigSourceFile(gucname, &linenum) : NULL;
ereport(ERROR,
(errcode_for_file_access(),
gucname ? errcontext("while loading shared libraries for setting \"%s\"", gucname) : 0,
- errmsg("could not access file \"%s\": %m",
- libname)));
+ sourcefile ? errcontext("from %s:%d", sourcefile, linenum) : 0,
+ errmsg("could not access file \"%s\": %s",
+ libname, errstr)));
+ }
for (file_scanner = file_list;
file_scanner != NULL &&
@@ -281,7 +288,7 @@ internal_load_library(const char *libname, const char *gucname)
}
else
{
- /* try to close library */
+ /* try to close library */ // Not needed due to ERROR ? //
dlclose(file_scanner->handle);
free((char *) file_scanner);
/* complain */
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 4e38e73a277..4e6fae2bd8b 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -8577,6 +8577,30 @@ GetConfigOptionFlags(const char *name, bool missing_ok)
return record->flags;
}
+/*
+ * Get the source file and line associated with the given option, if it was set
+ * by a file.
+ *
+ * If the option doesn't exist, throw an ereport and don't return.
+ */
+char *
+GetConfigSourceFile(const char *name, int *linenum)
+{
+ struct config_generic *record;
+
+ record = find_option(name, false, false, ERROR);
+
+ /* Should not happen */
+ if (record == NULL)
+ return NULL;
+
+ if (record->source != PGC_S_FILE)
+ return NULL;
+
+ *linenum = record->sourceline;
+ return record->sourcefile;
+}
+
/*
* flatten_set_variable_args
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index e734493a484..cdb5e3488c5 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -367,6 +367,7 @@ extern const char *GetConfigOption(const char *name, bool missing_ok,
bool restrict_privileged);
extern const char *GetConfigOptionResetString(const char *name);
extern int GetConfigOptionFlags(const char *name, bool missing_ok);
+extern char *GetConfigSourceFile(const char *name, int *linenum);
extern void ProcessConfigFile(GucContext context);
extern char *convert_GUC_name_for_parameter_acl(const char *name);
extern bool check_GUC_name_for_parameter_acl(const char *name);
--
2.17.1
