On Wed, Feb 01, 2023 at 01:06:06PM -0800, Andres Freund wrote:
> On 2023-02-01 12:15:29 -0800, Nathan Bossart wrote:
>> Here's a new patch set in which I've attempted to address this feedback and
>> Michael's feedback.
>
> Looks better!
Thanks!
>> @@ -25,12 +34,14 @@ extern PGDLLIMPORT char *XLogArchiveLibrary;
>> * For more information about the purpose of each callback, refer to the
>> * archive modules documentation.
>> */
>> -typedef bool (*ArchiveCheckConfiguredCB) (void);
>> -typedef bool (*ArchiveFileCB) (const char *file, const char *path);
>> -typedef void (*ArchiveShutdownCB) (void);
>> +typedef void (*ArchiveStartupCB) (ArchiveModuleState *state);
>> +typedef bool (*ArchiveCheckConfiguredCB) (ArchiveModuleState *state);
>> +typedef bool (*ArchiveFileCB) (const char *file, const char *path,
>> ArchiveModuleState *state);
>> +typedef void (*ArchiveShutdownCB) (ArchiveModuleState *state);
>
> Personally I'd always pass ArchiveModuleState *state as the first arg,
> but it's not important.
Yeah, that's nicer. cfbot is complaining about a missing #include, so I
need to send a new revision anyway.
--
Nathan Bossart
Amazon Web Services: https://aws.amazon.com
>From e54ed061b772e7f0859a37612ed1effebc5c6ba1 Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathandboss...@gmail.com>
Date: Fri, 27 Jan 2023 21:01:22 -0800
Subject: [PATCH v4 1/3] s/ArchiveContext/ArchiveCallbacks
---
src/backend/postmaster/pgarch.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/src/backend/postmaster/pgarch.c b/src/backend/postmaster/pgarch.c
index 3c714a79c6..dda6698509 100644
--- a/src/backend/postmaster/pgarch.c
+++ b/src/backend/postmaster/pgarch.c
@@ -97,7 +97,7 @@ char *XLogArchiveLibrary = "";
*/
static time_t last_sigterm_time = 0;
static PgArchData *PgArch = NULL;
-static ArchiveModuleCallbacks ArchiveContext;
+static ArchiveModuleCallbacks ArchiveCallbacks;
/*
@@ -406,8 +406,8 @@ pgarch_ArchiverCopyLoop(void)
HandlePgArchInterrupts();
/* can't do anything if not configured ... */
- if (ArchiveContext.check_configured_cb != NULL &&
- !ArchiveContext.check_configured_cb())
+ if (ArchiveCallbacks.check_configured_cb != NULL &&
+ !ArchiveCallbacks.check_configured_cb())
{
ereport(WARNING,
(errmsg("archive_mode enabled, yet archiving is not configured")));
@@ -508,7 +508,7 @@ pgarch_archiveXlog(char *xlog)
snprintf(activitymsg, sizeof(activitymsg), "archiving %s", xlog);
set_ps_display(activitymsg);
- ret = ArchiveContext.archive_file_cb(xlog, pathname);
+ ret = ArchiveCallbacks.archive_file_cb(xlog, pathname);
if (ret)
snprintf(activitymsg, sizeof(activitymsg), "last was %s", xlog);
else
@@ -814,7 +814,7 @@ HandlePgArchInterrupts(void)
/*
* LoadArchiveLibrary
*
- * Loads the archiving callbacks into our local ArchiveContext.
+ * Loads the archiving callbacks into our local ArchiveCallbacks.
*/
static void
LoadArchiveLibrary(void)
@@ -827,7 +827,7 @@ LoadArchiveLibrary(void)
errmsg("both archive_command and archive_library set"),
errdetail("Only one of archive_command, archive_library may be set.")));
- memset(&ArchiveContext, 0, sizeof(ArchiveModuleCallbacks));
+ memset(&ArchiveCallbacks, 0, sizeof(ArchiveModuleCallbacks));
/*
* If shell archiving is enabled, use our special initialization function.
@@ -844,9 +844,9 @@ LoadArchiveLibrary(void)
ereport(ERROR,
(errmsg("archive modules have to define the symbol %s", "_PG_archive_module_init")));
- (*archive_init) (&ArchiveContext);
+ (*archive_init) (&ArchiveCallbacks);
- if (ArchiveContext.archive_file_cb == NULL)
+ if (ArchiveCallbacks.archive_file_cb == NULL)
ereport(ERROR,
(errmsg("archive modules must register an archive callback")));
@@ -859,6 +859,6 @@ LoadArchiveLibrary(void)
static void
pgarch_call_module_shutdown_cb(int code, Datum arg)
{
- if (ArchiveContext.shutdown_cb != NULL)
- ArchiveContext.shutdown_cb();
+ if (ArchiveCallbacks.shutdown_cb != NULL)
+ ArchiveCallbacks.shutdown_cb();
}
--
2.25.1
>From 37e19c986b548f5d281190e196e01ce94f8c4391 Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathandboss...@gmail.com>
Date: Fri, 27 Jan 2023 21:16:34 -0800
Subject: [PATCH v4 2/3] move archive module exports to dedicated headers
---
contrib/basic_archive/basic_archive.c | 2 +-
src/backend/postmaster/pgarch.c | 2 ++
src/backend/postmaster/shell_archive.c | 3 +-
src/backend/utils/misc/guc_tables.c | 1 +
src/include/postmaster/archive_module.h | 47 +++++++++++++++++++++++++
src/include/postmaster/pgarch.h | 39 --------------------
src/include/postmaster/shell_archive.h | 24 +++++++++++++
7 files changed, 77 insertions(+), 41 deletions(-)
create mode 100644 src/include/postmaster/archive_module.h
create mode 100644 src/include/postmaster/shell_archive.h
diff --git a/contrib/basic_archive/basic_archive.c b/contrib/basic_archive/basic_archive.c
index 3d29711a31..87bbb2174d 100644
--- a/contrib/basic_archive/basic_archive.c
+++ b/contrib/basic_archive/basic_archive.c
@@ -32,7 +32,7 @@
#include "common/int.h"
#include "miscadmin.h"
-#include "postmaster/pgarch.h"
+#include "postmaster/archive_module.h"
#include "storage/copydir.h"
#include "storage/fd.h"
#include "utils/guc.h"
diff --git a/src/backend/postmaster/pgarch.c b/src/backend/postmaster/pgarch.c
index dda6698509..ec47b2cc20 100644
--- a/src/backend/postmaster/pgarch.c
+++ b/src/backend/postmaster/pgarch.c
@@ -34,8 +34,10 @@
#include "lib/binaryheap.h"
#include "libpq/pqsignal.h"
#include "pgstat.h"
+#include "postmaster/archive_module.h"
#include "postmaster/interrupt.h"
#include "postmaster/pgarch.h"
+#include "postmaster/shell_archive.h"
#include "storage/fd.h"
#include "storage/ipc.h"
#include "storage/latch.h"
diff --git a/src/backend/postmaster/shell_archive.c b/src/backend/postmaster/shell_archive.c
index 806b81c3f2..35f88c1222 100644
--- a/src/backend/postmaster/shell_archive.c
+++ b/src/backend/postmaster/shell_archive.c
@@ -20,7 +20,8 @@
#include "access/xlog.h"
#include "common/percentrepl.h"
#include "pgstat.h"
-#include "postmaster/pgarch.h"
+#include "postmaster/archive_module.h"
+#include "postmaster/shell_archive.h"
static bool shell_archive_configured(void);
static bool shell_archive_file(const char *file, const char *path);
diff --git a/src/backend/utils/misc/guc_tables.c b/src/backend/utils/misc/guc_tables.c
index c5a95f5dcc..663c6e0011 100644
--- a/src/backend/utils/misc/guc_tables.c
+++ b/src/backend/utils/misc/guc_tables.c
@@ -52,6 +52,7 @@
#include "parser/parse_expr.h"
#include "parser/parser.h"
#include "pgstat.h"
+#include "postmaster/archive_module.h"
#include "postmaster/autovacuum.h"
#include "postmaster/bgworker_internals.h"
#include "postmaster/bgwriter.h"
diff --git a/src/include/postmaster/archive_module.h b/src/include/postmaster/archive_module.h
new file mode 100644
index 0000000000..f5015ff95d
--- /dev/null
+++ b/src/include/postmaster/archive_module.h
@@ -0,0 +1,47 @@
+/*-------------------------------------------------------------------------
+ *
+ * archive_module.h
+ * Exports for archive modules.
+ *
+ * Copyright (c) 2022-2023, PostgreSQL Global Development Group
+ *
+ * src/include/postmaster/archive_module.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef _ARCHIVE_MODULE_H
+#define _ARCHIVE_MODULE_H
+
+/*
+ * The value of the archive_library GUC.
+ */
+extern PGDLLIMPORT char *XLogArchiveLibrary;
+
+/*
+ * Archive module callbacks
+ *
+ * These callback functions should be defined by archive libraries and returned
+ * via _PG_archive_module_init(). ArchiveFileCB is the only required callback.
+ * For more information about the purpose of each callback, refer to the
+ * archive modules documentation.
+ */
+typedef bool (*ArchiveCheckConfiguredCB) (void);
+typedef bool (*ArchiveFileCB) (const char *file, const char *path);
+typedef void (*ArchiveShutdownCB) (void);
+
+typedef struct ArchiveModuleCallbacks
+{
+ ArchiveCheckConfiguredCB check_configured_cb;
+ ArchiveFileCB archive_file_cb;
+ ArchiveShutdownCB shutdown_cb;
+} ArchiveModuleCallbacks;
+
+/*
+ * Type of the shared library symbol _PG_archive_module_init that is looked
+ * up when loading an archive library.
+ */
+typedef void (*ArchiveModuleInit) (ArchiveModuleCallbacks *cb);
+
+extern PGDLLEXPORT void _PG_archive_module_init(ArchiveModuleCallbacks *cb);
+
+#endif /* _ARCHIVE_MODULE_H */
diff --git a/src/include/postmaster/pgarch.h b/src/include/postmaster/pgarch.h
index bcd51dfad6..3bd4fac71e 100644
--- a/src/include/postmaster/pgarch.h
+++ b/src/include/postmaster/pgarch.h
@@ -33,43 +33,4 @@ extern void PgArchiverMain(void) pg_attribute_noreturn();
extern void PgArchWakeup(void);
extern void PgArchForceDirScan(void);
-/*
- * The value of the archive_library GUC.
- */
-extern PGDLLIMPORT char *XLogArchiveLibrary;
-
-/*
- * Archive module callbacks
- *
- * These callback functions should be defined by archive libraries and returned
- * via _PG_archive_module_init(). ArchiveFileCB is the only required callback.
- * For more information about the purpose of each callback, refer to the
- * archive modules documentation.
- */
-typedef bool (*ArchiveCheckConfiguredCB) (void);
-typedef bool (*ArchiveFileCB) (const char *file, const char *path);
-typedef void (*ArchiveShutdownCB) (void);
-
-typedef struct ArchiveModuleCallbacks
-{
- ArchiveCheckConfiguredCB check_configured_cb;
- ArchiveFileCB archive_file_cb;
- ArchiveShutdownCB shutdown_cb;
-} ArchiveModuleCallbacks;
-
-/*
- * Type of the shared library symbol _PG_archive_module_init that is looked
- * up when loading an archive library.
- */
-typedef void (*ArchiveModuleInit) (ArchiveModuleCallbacks *cb);
-
-extern PGDLLEXPORT void _PG_archive_module_init(ArchiveModuleCallbacks *cb);
-
-/*
- * Since the logic for archiving via a shell command is in the core server
- * and does not need to be loaded via a shared library, it has a special
- * initialization function.
- */
-extern void shell_archive_init(ArchiveModuleCallbacks *cb);
-
#endif /* _PGARCH_H */
diff --git a/src/include/postmaster/shell_archive.h b/src/include/postmaster/shell_archive.h
new file mode 100644
index 0000000000..3cf737ce8e
--- /dev/null
+++ b/src/include/postmaster/shell_archive.h
@@ -0,0 +1,24 @@
+/*-------------------------------------------------------------------------
+ *
+ * shell_archive.h
+ * Exports for archiving via shell.
+ *
+ * Copyright (c) 2022-2023, PostgreSQL Global Development Group
+ *
+ * src/include/postmaster/shell_archive.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef _SHELL_ARCHIVE_H
+#define _SHELL_ARCHIVE_H
+
+#include "postmaster/archive_module.h"
+
+/*
+ * Since the logic for archiving via a shell command is in the core server
+ * and does not need to be loaded via a shared library, it has a special
+ * initialization function.
+ */
+extern void shell_archive_init(ArchiveModuleCallbacks *cb);
+
+#endif /* _SHELL_ARCHIVE_H */
--
2.25.1
>From 4efe9de26a6ab1a1b606f723cc0ef7422bff0767 Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathandboss...@gmail.com>
Date: Tue, 31 Jan 2023 14:58:40 -0800
Subject: [PATCH v4 3/3] restructure archive modules API
---
contrib/basic_archive/basic_archive.c | 51 ++++++++++++++++++-------
doc/src/sgml/archive-modules.sgml | 33 +++++++++++++---
src/backend/postmaster/pgarch.c | 23 ++++++-----
src/backend/postmaster/shell_archive.c | 29 ++++++++------
src/include/postmaster/archive_module.h | 21 +++++++---
src/include/postmaster/shell_archive.h | 2 +-
6 files changed, 112 insertions(+), 47 deletions(-)
diff --git a/contrib/basic_archive/basic_archive.c b/contrib/basic_archive/basic_archive.c
index 87bbb2174d..3b4373b562 100644
--- a/contrib/basic_archive/basic_archive.c
+++ b/contrib/basic_archive/basic_archive.c
@@ -40,15 +40,27 @@
PG_MODULE_MAGIC;
+typedef struct BasicArchiveData
+{
+ MemoryContext context;
+} BasicArchiveData;
+
static char *archive_directory = NULL;
-static MemoryContext basic_archive_context;
-static bool basic_archive_configured(void);
-static bool basic_archive_file(const char *file, const char *path);
+static void basic_archive_startup(ArchiveModuleState *state);
+static bool basic_archive_configured(ArchiveModuleState *state);
+static bool basic_archive_file(ArchiveModuleState *state, const char *file, const char *path);
static void basic_archive_file_internal(const char *file, const char *path);
static bool check_archive_directory(char **newval, void **extra, GucSource source);
static bool compare_files(const char *file1, const char *file2);
+static const ArchiveModuleCallbacks basic_archive_callbacks = {
+ .startup_cb = basic_archive_startup,
+ .check_configured_cb = basic_archive_configured,
+ .archive_file_cb = basic_archive_file,
+ .shutdown_cb = NULL
+};
+
/*
* _PG_init
*
@@ -67,10 +79,6 @@ _PG_init(void)
check_archive_directory, NULL, NULL);
MarkGUCPrefixReserved("basic_archive");
-
- basic_archive_context = AllocSetContextCreate(TopMemoryContext,
- "basic_archive",
- ALLOCSET_DEFAULT_SIZES);
}
/*
@@ -78,13 +86,28 @@ _PG_init(void)
*
* Returns the module's archiving callbacks.
*/
-void
-_PG_archive_module_init(ArchiveModuleCallbacks *cb)
+const ArchiveModuleCallbacks *
+_PG_archive_module_init(void)
{
AssertVariableIsOfType(&_PG_archive_module_init, ArchiveModuleInit);
- cb->check_configured_cb = basic_archive_configured;
- cb->archive_file_cb = basic_archive_file;
+ return &basic_archive_callbacks;
+}
+
+/*
+ * basic_archive_startup
+ *
+ * Creates the module's memory context.
+ */
+void
+basic_archive_startup(ArchiveModuleState *state)
+{
+ BasicArchiveData *data = palloc0(sizeof(BasicArchiveData));
+
+ data->context = AllocSetContextCreate(TopMemoryContext,
+ "basic_archive",
+ ALLOCSET_DEFAULT_SIZES);
+ state->private_data = (void *) data;
}
/*
@@ -135,7 +158,7 @@ check_archive_directory(char **newval, void **extra, GucSource source)
* Checks that archive_directory is not blank.
*/
static bool
-basic_archive_configured(void)
+basic_archive_configured(ArchiveModuleState *state)
{
return archive_directory != NULL && archive_directory[0] != '\0';
}
@@ -146,10 +169,12 @@ basic_archive_configured(void)
* Archives one file.
*/
static bool
-basic_archive_file(const char *file, const char *path)
+basic_archive_file(ArchiveModuleState *state, const char *file, const char *path)
{
sigjmp_buf local_sigjmp_buf;
MemoryContext oldcontext;
+ BasicArchiveData *data = (BasicArchiveData *) (state->private_data);
+ MemoryContext basic_archive_context = data->context;
/*
* We run basic_archive_file_internal() in our own memory context so that
diff --git a/doc/src/sgml/archive-modules.sgml b/doc/src/sgml/archive-modules.sgml
index ef02051f7f..2ec5d12d97 100644
--- a/doc/src/sgml/archive-modules.sgml
+++ b/doc/src/sgml/archive-modules.sgml
@@ -47,23 +47,30 @@
normal library search path is used to locate the library. To provide the
required archive module callbacks and to indicate that the library is
actually an archive module, it needs to provide a function named
- <function>_PG_archive_module_init</function>. This function is passed a
- struct that needs to be filled with the callback function pointers for
+ <function>_PG_archive_module_init</function>. This function must return an
+ ArchiveModuleCallbacks struct filled with the callback function pointers for
individual actions.
<programlisting>
typedef struct ArchiveModuleCallbacks
{
+ ArchiveStartupCB startup_cb;
ArchiveCheckConfiguredCB check_configured_cb;
ArchiveFileCB archive_file_cb;
ArchiveShutdownCB shutdown_cb;
} ArchiveModuleCallbacks;
-typedef void (*ArchiveModuleInit) (struct ArchiveModuleCallbacks *cb);
+typedef const ArchiveModuleCallbacks *(*ArchiveModuleInit) (void);
</programlisting>
Only the <function>archive_file_cb</function> callback is required. The
others are optional.
</para>
+
+ <note>
+ <para>
+ <varname>archive_library</varname> is only loaded in the archiver process.
+ </para>
+ </note>
</sect1>
<sect1 id="archive-module-callbacks">
@@ -73,6 +80,20 @@ typedef void (*ArchiveModuleInit) (struct ArchiveModuleCallbacks *cb);
The server will call them as required to process each individual WAL file.
</para>
+ <sect2 id="archive-module-startup">
+ <title>Startup Callback</title>
+ <para>
+ The <function>startup_cb</function> callback is called shortly after the
+ module is loaded. This callback can be used to perform any additional
+ initialization required. If the archive module needs to have a state, it
+ can use <literal>state->private_data</literal> to store it.
+
+<programlisting>
+typedef void (*ArchiveStartupCB) (ArchiveModuleState *state);
+</programlisting>
+ </para>
+ </sect2>
+
<sect2 id="archive-module-check">
<title>Check Callback</title>
<para>
@@ -83,7 +104,7 @@ typedef void (*ArchiveModuleInit) (struct ArchiveModuleCallbacks *cb);
assumes the module is configured.
<programlisting>
-typedef bool (*ArchiveCheckConfiguredCB) (void);
+typedef bool (*ArchiveCheckConfiguredCB) (ArchiveModuleState *state);
</programlisting>
If <literal>true</literal> is returned, the server will proceed with
@@ -105,7 +126,7 @@ WARNING: archive_mode enabled, yet archiving is not configured
single WAL file.
<programlisting>
-typedef bool (*ArchiveFileCB) (const char *file, const char *path);
+typedef bool (*ArchiveFileCB) (ArchiveModuleState *state, const char *file, const char *path);
</programlisting>
If <literal>true</literal> is returned, the server proceeds as if the file
@@ -128,7 +149,7 @@ typedef bool (*ArchiveFileCB) (const char *file, const char *path);
these situations.
<programlisting>
-typedef void (*ArchiveShutdownCB) (void);
+typedef void (*ArchiveShutdownCB) (ArchiveModuleState *state);
</programlisting>
</para>
</sect2>
diff --git a/src/backend/postmaster/pgarch.c b/src/backend/postmaster/pgarch.c
index ec47b2cc20..5931d5ffa0 100644
--- a/src/backend/postmaster/pgarch.c
+++ b/src/backend/postmaster/pgarch.c
@@ -99,7 +99,8 @@ char *XLogArchiveLibrary = "";
*/
static time_t last_sigterm_time = 0;
static PgArchData *PgArch = NULL;
-static ArchiveModuleCallbacks ArchiveCallbacks;
+static const ArchiveModuleCallbacks *ArchiveCallbacks;
+static ArchiveModuleState *archive_module_state;
/*
@@ -408,8 +409,8 @@ pgarch_ArchiverCopyLoop(void)
HandlePgArchInterrupts();
/* can't do anything if not configured ... */
- if (ArchiveCallbacks.check_configured_cb != NULL &&
- !ArchiveCallbacks.check_configured_cb())
+ if (ArchiveCallbacks->check_configured_cb != NULL &&
+ !ArchiveCallbacks->check_configured_cb(archive_module_state))
{
ereport(WARNING,
(errmsg("archive_mode enabled, yet archiving is not configured")));
@@ -510,7 +511,7 @@ pgarch_archiveXlog(char *xlog)
snprintf(activitymsg, sizeof(activitymsg), "archiving %s", xlog);
set_ps_display(activitymsg);
- ret = ArchiveCallbacks.archive_file_cb(xlog, pathname);
+ ret = ArchiveCallbacks->archive_file_cb(archive_module_state, xlog, pathname);
if (ret)
snprintf(activitymsg, sizeof(activitymsg), "last was %s", xlog);
else
@@ -829,8 +830,6 @@ LoadArchiveLibrary(void)
errmsg("both archive_command and archive_library set"),
errdetail("Only one of archive_command, archive_library may be set.")));
- memset(&ArchiveCallbacks, 0, sizeof(ArchiveModuleCallbacks));
-
/*
* If shell archiving is enabled, use our special initialization function.
* Otherwise, load the library and call its _PG_archive_module_init().
@@ -846,12 +845,16 @@ LoadArchiveLibrary(void)
ereport(ERROR,
(errmsg("archive modules have to define the symbol %s", "_PG_archive_module_init")));
- (*archive_init) (&ArchiveCallbacks);
+ ArchiveCallbacks = (*archive_init) ();
- if (ArchiveCallbacks.archive_file_cb == NULL)
+ if (ArchiveCallbacks->archive_file_cb == NULL)
ereport(ERROR,
(errmsg("archive modules must register an archive callback")));
+ archive_module_state = (ArchiveModuleState *) palloc0(sizeof(ArchiveModuleState));
+ if (ArchiveCallbacks->startup_cb != NULL)
+ ArchiveCallbacks->startup_cb(archive_module_state);
+
before_shmem_exit(pgarch_call_module_shutdown_cb, 0);
}
@@ -861,6 +864,6 @@ LoadArchiveLibrary(void)
static void
pgarch_call_module_shutdown_cb(int code, Datum arg)
{
- if (ArchiveCallbacks.shutdown_cb != NULL)
- ArchiveCallbacks.shutdown_cb();
+ if (ArchiveCallbacks->shutdown_cb != NULL)
+ ArchiveCallbacks->shutdown_cb(archive_module_state);
}
diff --git a/src/backend/postmaster/shell_archive.c b/src/backend/postmaster/shell_archive.c
index 35f88c1222..cc2585218d 100644
--- a/src/backend/postmaster/shell_archive.c
+++ b/src/backend/postmaster/shell_archive.c
@@ -23,28 +23,33 @@
#include "postmaster/archive_module.h"
#include "postmaster/shell_archive.h"
-static bool shell_archive_configured(void);
-static bool shell_archive_file(const char *file, const char *path);
-static void shell_archive_shutdown(void);
-
-void
-shell_archive_init(ArchiveModuleCallbacks *cb)
+static bool shell_archive_configured(ArchiveModuleState *state);
+static bool shell_archive_file(ArchiveModuleState *state, const char *file, const char *path);
+static void shell_archive_shutdown(ArchiveModuleState *state);
+
+static const ArchiveModuleCallbacks shell_archive_callbacks = {
+ .startup_cb = NULL,
+ .check_configured_cb = shell_archive_configured,
+ .archive_file_cb = shell_archive_file,
+ .shutdown_cb = shell_archive_shutdown
+};
+
+const ArchiveModuleCallbacks *
+shell_archive_init(void)
{
AssertVariableIsOfType(&shell_archive_init, ArchiveModuleInit);
- cb->check_configured_cb = shell_archive_configured;
- cb->archive_file_cb = shell_archive_file;
- cb->shutdown_cb = shell_archive_shutdown;
+ return &shell_archive_callbacks;
}
static bool
-shell_archive_configured(void)
+shell_archive_configured(ArchiveModuleState *state)
{
return XLogArchiveCommand[0] != '\0';
}
static bool
-shell_archive_file(const char *file, const char *path)
+shell_archive_file(ArchiveModuleState *state, const char *file, const char *path)
{
char *xlogarchcmd;
char *nativePath = NULL;
@@ -126,7 +131,7 @@ shell_archive_file(const char *file, const char *path)
}
static void
-shell_archive_shutdown(void)
+shell_archive_shutdown(ArchiveModuleState *state)
{
elog(DEBUG1, "archiver process shutting down");
}
diff --git a/src/include/postmaster/archive_module.h b/src/include/postmaster/archive_module.h
index f5015ff95d..79e9d53534 100644
--- a/src/include/postmaster/archive_module.h
+++ b/src/include/postmaster/archive_module.h
@@ -17,6 +17,15 @@
*/
extern PGDLLIMPORT char *XLogArchiveLibrary;
+typedef struct ArchiveModuleState
+{
+ /*
+ * Private data pointer for use by an archive module. This can be used to
+ * store state for the module that will be passed to each of its callbacks.
+ */
+ void *private_data;
+} ArchiveModuleState;
+
/*
* Archive module callbacks
*
@@ -25,12 +34,14 @@ extern PGDLLIMPORT char *XLogArchiveLibrary;
* For more information about the purpose of each callback, refer to the
* archive modules documentation.
*/
-typedef bool (*ArchiveCheckConfiguredCB) (void);
-typedef bool (*ArchiveFileCB) (const char *file, const char *path);
-typedef void (*ArchiveShutdownCB) (void);
+typedef void (*ArchiveStartupCB) (ArchiveModuleState *state);
+typedef bool (*ArchiveCheckConfiguredCB) (ArchiveModuleState *state);
+typedef bool (*ArchiveFileCB) (ArchiveModuleState *state, const char *file, const char *path);
+typedef void (*ArchiveShutdownCB) (ArchiveModuleState *state);
typedef struct ArchiveModuleCallbacks
{
+ ArchiveStartupCB startup_cb;
ArchiveCheckConfiguredCB check_configured_cb;
ArchiveFileCB archive_file_cb;
ArchiveShutdownCB shutdown_cb;
@@ -40,8 +51,8 @@ typedef struct ArchiveModuleCallbacks
* Type of the shared library symbol _PG_archive_module_init that is looked
* up when loading an archive library.
*/
-typedef void (*ArchiveModuleInit) (ArchiveModuleCallbacks *cb);
+typedef const ArchiveModuleCallbacks *(*ArchiveModuleInit) (void);
-extern PGDLLEXPORT void _PG_archive_module_init(ArchiveModuleCallbacks *cb);
+extern PGDLLEXPORT const ArchiveModuleCallbacks *_PG_archive_module_init(void);
#endif /* _ARCHIVE_MODULE_H */
diff --git a/src/include/postmaster/shell_archive.h b/src/include/postmaster/shell_archive.h
index 3cf737ce8e..be83c7715a 100644
--- a/src/include/postmaster/shell_archive.h
+++ b/src/include/postmaster/shell_archive.h
@@ -19,6 +19,6 @@
* and does not need to be loaded via a shared library, it has a special
* initialization function.
*/
-extern void shell_archive_init(ArchiveModuleCallbacks *cb);
+extern const ArchiveModuleCallbacks *shell_archive_init(void);
#endif /* _SHELL_ARCHIVE_H */
--
2.25.1
