Bonjour Michaël,
The query cancellation added to pgbench is different than the actual
refactoring, and it is a result of the refactoring, so I would rather
split that into two different commits for clarity. The split is easy
enough, so that's fine not to send two different patches.
Yep, different file set.
Compilation of the patch fails for me on Windows for psql:
unresolved external symbol sigint_interrupt_jmp
Please note that Mr Robot complains as well at build time:
http://commitfest.cputube.org/fabien-coelho.html
Visibly the problem here is that sigint_interrupt_jmp is declared in
common.h, but you have moved it to a non-WIN32 section of the code in
psql/common.c. And actually, note that copy.c and mainloop.c make use
of it...
Indeed.
I would not worry much about SIGTERM as you mentioned in the comments,
query cancellations are associated to SIGINT now. There could be an
argument possible later to allow passing down a custom signal though.
Ok.
Attached is an updated patch with a couple of edits I have done,
including the removal of some noise diffs and the previous edits.
Thanks!
I am switching the patch as waiting on author, bumping it to next CF at
the same time. Could you please fix the Windows issue?
I do not have a Windows host, so I can only do blind tests. I just moved
the declaration out of !WIN32 scope in attached v7, which might solve the
resolution error. All other issues pointed out above seem fixed in the v6
you sent.
--
Fabien.
diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c
index 4a7ac1f821..5129aea516 100644
--- a/src/bin/pgbench/pgbench.c
+++ b/src/bin/pgbench/pgbench.c
@@ -59,6 +59,7 @@
#include "common/int.h"
#include "common/logging.h"
+#include "fe_utils/cancel.h"
#include "fe_utils/conditional.h"
#include "getopt_long.h"
#include "libpq-fe.h"
@@ -3894,6 +3895,9 @@ initGenerateDataClientSide(PGconn *con)
exit(1);
}
+ if (CancelRequested)
+ break;
+
/*
* If we want to stick with the original logging, print a message each
* 100k inserted rows.
@@ -4109,6 +4113,9 @@ runInitSteps(const char *initialize_steps)
if ((con = doConnect()) == NULL)
exit(1);
+ setup_cancel_handler(NULL);
+ SetCancelConn(con);
+
for (step = initialize_steps; *step != '\0'; step++)
{
instr_time start;
@@ -4176,6 +4183,7 @@ runInitSteps(const char *initialize_steps)
}
fprintf(stderr, "done in %.2f s (%s).\n", run_time, stats.data);
+ ResetCancelConn();
PQfinish(con);
termPQExpBuffer(&stats);
}
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index 0a2597046d..48b6279403 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -29,6 +29,7 @@
#include "copy.h"
#include "crosstabview.h"
#include "describe.h"
+#include "fe_utils/cancel.h"
#include "fe_utils/print.h"
#include "fe_utils/string_utils.h"
#include "help.h"
diff --git a/src/bin/psql/common.c b/src/bin/psql/common.c
index 53a1ea2bdb..442ff2fe5d 100644
--- a/src/bin/psql/common.c
+++ b/src/bin/psql/common.c
@@ -23,6 +23,7 @@
#include "common/logging.h"
#include "copy.h"
#include "crosstabview.h"
+#include "fe_utils/cancel.h"
#include "fe_utils/mbprint.h"
#include "fe_utils/string_utils.h"
#include "portability/instr_time.h"
@@ -241,7 +242,7 @@ NoticeProcessor(void *arg, const char *message)
*
* SIGINT is supposed to abort all long-running psql operations, not only
* database queries. In most places, this is accomplished by checking
- * cancel_pressed during long-running loops. However, that won't work when
+ * CancelRequested during long-running loops. However, that won't work when
* blocked on user input (in readline() or fgets()). In those places, we
* set sigint_interrupt_enabled true while blocked, instructing the signal
* catcher to longjmp through sigint_interrupt_jmp. We assume readline and
@@ -252,34 +253,11 @@ volatile bool sigint_interrupt_enabled = false;
sigjmp_buf sigint_interrupt_jmp;
-static PGcancel *volatile cancelConn = NULL;
-
-#ifdef WIN32
-static CRITICAL_SECTION cancelConnLock;
-#endif
-
-/*
- * Write a simple string to stderr --- must be safe in a signal handler.
- * We ignore the write() result since there's not much we could do about it.
- * Certain compilers make that harder than it ought to be.
- */
-#define write_stderr(str) \
- do { \
- const char *str_ = (str); \
- int rc_; \
- rc_ = write(fileno(stderr), str_, strlen(str_)); \
- (void) rc_; \
- } while (0)
-
-
#ifndef WIN32
static void
-handle_sigint(SIGNAL_ARGS)
+psql_sigint_callback(void)
{
- int save_errno = errno;
- char errbuf[256];
-
/* if we are waiting for input, longjmp out of it */
if (sigint_interrupt_enabled)
{
@@ -288,74 +266,20 @@ handle_sigint(SIGNAL_ARGS)
}
/* else, set cancel flag to stop any long-running loops */
- cancel_pressed = true;
-
- /* and send QueryCancel if we are processing a database query */
- if (cancelConn != NULL)
- {
- if (PQcancel(cancelConn, errbuf, sizeof(errbuf)))
- write_stderr("Cancel request sent\n");
- else
- {
- write_stderr("Could not send cancel request: ");
- write_stderr(errbuf);
- }
- }
-
- errno = save_errno; /* just in case the write changed it */
+ CancelRequested = true;
}
-void
-setup_cancel_handler(void)
-{
- pqsignal(SIGINT, handle_sigint);
-}
-#else /* WIN32 */
-
-static BOOL WINAPI
-consoleHandler(DWORD dwCtrlType)
-{
- char errbuf[256];
-
- if (dwCtrlType == CTRL_C_EVENT ||
- dwCtrlType == CTRL_BREAK_EVENT)
- {
- /*
- * Can't longjmp here, because we are in wrong thread :-(
- */
-
- /* set cancel flag to stop any long-running loops */
- cancel_pressed = true;
-
- /* and send QueryCancel if we are processing a database query */
- EnterCriticalSection(&cancelConnLock);
- if (cancelConn != NULL)
- {
- if (PQcancel(cancelConn, errbuf, sizeof(errbuf)))
- write_stderr("Cancel request sent\n");
- else
- {
- write_stderr("Could not send cancel request: ");
- write_stderr(errbuf);
- }
- }
- LeaveCriticalSection(&cancelConnLock);
-
- return TRUE;
- }
- else
- /* Return FALSE for any signals not being handled */
- return FALSE;
-}
+#endif /* !WIN32 */
void
-setup_cancel_handler(void)
+psql_setup_cancel_handler(void)
{
- InitializeCriticalSection(&cancelConnLock);
-
- SetConsoleCtrlHandler(consoleHandler, TRUE);
+#ifndef WIN32
+ setup_cancel_handler(psql_sigint_callback);
+#else
+ setup_cancel_handler(NULL);
+#endif /* WIN32 */
}
-#endif /* WIN32 */
/* ConnectionUp
@@ -428,62 +352,6 @@ CheckConnection(void)
-/*
- * SetCancelConn
- *
- * Set cancelConn to point to the current database connection.
- */
-void
-SetCancelConn(void)
-{
- PGcancel *oldCancelConn;
-
-#ifdef WIN32
- EnterCriticalSection(&cancelConnLock);
-#endif
-
- /* Free the old one if we have one */
- oldCancelConn = cancelConn;
- /* be sure handle_sigint doesn't use pointer while freeing */
- cancelConn = NULL;
-
- if (oldCancelConn != NULL)
- PQfreeCancel(oldCancelConn);
-
- cancelConn = PQgetCancel(pset.db);
-
-#ifdef WIN32
- LeaveCriticalSection(&cancelConnLock);
-#endif
-}
-
-
-/*
- * ResetCancelConn
- *
- * Free the current cancel connection, if any, and set to NULL.
- */
-void
-ResetCancelConn(void)
-{
- PGcancel *oldCancelConn;
-
-#ifdef WIN32
- EnterCriticalSection(&cancelConnLock);
-#endif
-
- oldCancelConn = cancelConn;
- /* be sure handle_sigint doesn't use pointer while freeing */
- cancelConn = NULL;
-
- if (oldCancelConn != NULL)
- PQfreeCancel(oldCancelConn);
-
-#ifdef WIN32
- LeaveCriticalSection(&cancelConnLock);
-#endif
-}
-
/*
* AcceptResult
@@ -707,7 +575,7 @@ PSQLexec(const char *query)
return NULL;
}
- SetCancelConn();
+ SetCancelConn(pset.db);
res = PQexec(pset.db, query);
@@ -746,7 +614,7 @@ PSQLexecWatch(const char *query, const printQueryOpt *opt)
return 0;
}
- SetCancelConn();
+ SetCancelConn(pset.db);
if (pset.timing)
INSTR_TIME_SET_CURRENT(before);
@@ -773,7 +641,7 @@ PSQLexecWatch(const char *query, const printQueryOpt *opt)
* consumed. The user's intention, though, is to cancel the entire watch
* process, so detect a sent cancellation request and exit in this case.
*/
- if (cancel_pressed)
+ if (CancelRequested)
{
PQclear(res);
return 0;
@@ -973,8 +841,8 @@ ExecQueryTuples(const PGresult *result)
{
const char *query = PQgetvalue(result, r, c);
- /* Abandon execution if cancel_pressed */
- if (cancel_pressed)
+ /* Abandon execution if CancelRequested */
+ if (CancelRequested)
goto loop_exit;
/*
@@ -1091,7 +959,7 @@ ProcessResult(PGresult **results)
FILE *copystream;
PGresult *copy_result;
- SetCancelConn();
+ SetCancelConn(pset.db);
if (result_status == PGRES_COPY_OUT)
{
bool need_close = false;
@@ -1342,7 +1210,7 @@ SendQuery(const char *query)
if (fgets(buf, sizeof(buf), stdin) != NULL)
if (buf[0] == 'x')
goto sendquery_cleanup;
- if (cancel_pressed)
+ if (CancelRequested)
goto sendquery_cleanup;
}
else if (pset.echo == PSQL_ECHO_QUERIES)
@@ -1360,7 +1228,7 @@ SendQuery(const char *query)
fflush(pset.logfile);
}
- SetCancelConn();
+ SetCancelConn(pset.db);
transaction_status = PQtransactionStatus(pset.db);
@@ -1886,7 +1754,7 @@ ExecQueryUsingCursor(const char *query, double *elapsed_msec)
* writing things to the stream, we presume $PAGER has disappeared and
* stop bothering to pull down more data.
*/
- if (ntuples < fetch_count || cancel_pressed || flush_error ||
+ if (ntuples < fetch_count || CancelRequested || flush_error ||
ferror(fout))
break;
}
diff --git a/src/bin/psql/common.h b/src/bin/psql/common.h
index 292dc54919..60ff9f1758 100644
--- a/src/bin/psql/common.h
+++ b/src/bin/psql/common.h
@@ -26,10 +26,7 @@ extern volatile bool sigint_interrupt_enabled;
extern sigjmp_buf sigint_interrupt_jmp;
-extern void setup_cancel_handler(void);
-
-extern void SetCancelConn(void);
-extern void ResetCancelConn(void);
+extern void psql_setup_cancel_handler(void);
extern PGresult *PSQLexec(const char *query);
extern int PSQLexecWatch(const char *query, const printQueryOpt *opt);
diff --git a/src/bin/psql/large_obj.c b/src/bin/psql/large_obj.c
index 042403e0f7..75b733c3c8 100644
--- a/src/bin/psql/large_obj.c
+++ b/src/bin/psql/large_obj.c
@@ -9,6 +9,7 @@
#include "common.h"
#include "common/logging.h"
+#include "fe_utils/cancel.h"
#include "large_obj.h"
#include "settings.h"
@@ -146,7 +147,7 @@ do_lo_export(const char *loid_arg, const char *filename_arg)
if (!start_lo_xact("\\lo_export", &own_transaction))
return false;
- SetCancelConn();
+ SetCancelConn(NULL);
status = lo_export(pset.db, atooid(loid_arg), filename_arg);
ResetCancelConn();
@@ -182,7 +183,7 @@ do_lo_import(const char *filename_arg, const char *comment_arg)
if (!start_lo_xact("\\lo_import", &own_transaction))
return false;
- SetCancelConn();
+ SetCancelConn(NULL);
loid = lo_import(pset.db, filename_arg);
ResetCancelConn();
@@ -244,7 +245,7 @@ do_lo_unlink(const char *loid_arg)
if (!start_lo_xact("\\lo_unlink", &own_transaction))
return false;
- SetCancelConn();
+ SetCancelConn(NULL);
status = lo_unlink(pset.db, loid);
ResetCancelConn();
diff --git a/src/bin/psql/startup.c b/src/bin/psql/startup.c
index 0d941ef5ba..43cf139a31 100644
--- a/src/bin/psql/startup.c
+++ b/src/bin/psql/startup.c
@@ -301,7 +301,7 @@ main(int argc, char *argv[])
exit(EXIT_BADCONN);
}
- setup_cancel_handler();
+ psql_setup_cancel_handler();
PQsetNoticeProcessor(pset.db, NoticeProcessor, NULL);
diff --git a/src/bin/scripts/clusterdb.c b/src/bin/scripts/clusterdb.c
index d380127356..3aee5f2834 100644
--- a/src/bin/scripts/clusterdb.c
+++ b/src/bin/scripts/clusterdb.c
@@ -133,7 +133,7 @@ main(int argc, char *argv[])
exit(1);
}
- setup_cancel_handler();
+ setup_cancel_handler(NULL);
if (alldb)
{
diff --git a/src/bin/scripts/common.c b/src/bin/scripts/common.c
index 1b38a1da49..d2a7547441 100644
--- a/src/bin/scripts/common.c
+++ b/src/bin/scripts/common.c
@@ -24,14 +24,6 @@
#define ERRCODE_UNDEFINED_TABLE "42P01"
-
-static PGcancel *volatile cancelConn = NULL;
-bool CancelRequested = false;
-
-#ifdef WIN32
-static CRITICAL_SECTION cancelConnLock;
-#endif
-
/*
* Provide strictly harmonized handling of --help and --version
* options.
@@ -465,142 +457,3 @@ yesno_prompt(const char *question)
_(PG_YESLETTER), _(PG_NOLETTER));
}
}
-
-/*
- * SetCancelConn
- *
- * Set cancelConn to point to the current database connection.
- */
-void
-SetCancelConn(PGconn *conn)
-{
- PGcancel *oldCancelConn;
-
-#ifdef WIN32
- EnterCriticalSection(&cancelConnLock);
-#endif
-
- /* Free the old one if we have one */
- oldCancelConn = cancelConn;
-
- /* be sure handle_sigint doesn't use pointer while freeing */
- cancelConn = NULL;
-
- if (oldCancelConn != NULL)
- PQfreeCancel(oldCancelConn);
-
- cancelConn = PQgetCancel(conn);
-
-#ifdef WIN32
- LeaveCriticalSection(&cancelConnLock);
-#endif
-}
-
-/*
- * ResetCancelConn
- *
- * Free the current cancel connection, if any, and set to NULL.
- */
-void
-ResetCancelConn(void)
-{
- PGcancel *oldCancelConn;
-
-#ifdef WIN32
- EnterCriticalSection(&cancelConnLock);
-#endif
-
- oldCancelConn = cancelConn;
-
- /* be sure handle_sigint doesn't use pointer while freeing */
- cancelConn = NULL;
-
- if (oldCancelConn != NULL)
- PQfreeCancel(oldCancelConn);
-
-#ifdef WIN32
- LeaveCriticalSection(&cancelConnLock);
-#endif
-}
-
-#ifndef WIN32
-/*
- * Handle interrupt signals by canceling the current command, if a cancelConn
- * is set.
- */
-static void
-handle_sigint(SIGNAL_ARGS)
-{
- int save_errno = errno;
- char errbuf[256];
-
- /* Send QueryCancel if we are processing a database query */
- if (cancelConn != NULL)
- {
- if (PQcancel(cancelConn, errbuf, sizeof(errbuf)))
- {
- CancelRequested = true;
- fprintf(stderr, _("Cancel request sent\n"));
- }
- else
- fprintf(stderr, _("Could not send cancel request: %s"), errbuf);
- }
- else
- CancelRequested = true;
-
- errno = save_errno; /* just in case the write changed it */
-}
-
-void
-setup_cancel_handler(void)
-{
- pqsignal(SIGINT, handle_sigint);
-}
-#else /* WIN32 */
-
-/*
- * Console control handler for Win32. Note that the control handler will
- * execute on a *different thread* than the main one, so we need to do
- * proper locking around those structures.
- */
-static BOOL WINAPI
-consoleHandler(DWORD dwCtrlType)
-{
- char errbuf[256];
-
- if (dwCtrlType == CTRL_C_EVENT ||
- dwCtrlType == CTRL_BREAK_EVENT)
- {
- /* Send QueryCancel if we are processing a database query */
- EnterCriticalSection(&cancelConnLock);
- if (cancelConn != NULL)
- {
- if (PQcancel(cancelConn, errbuf, sizeof(errbuf)))
- {
- fprintf(stderr, _("Cancel request sent\n"));
- CancelRequested = true;
- }
- else
- fprintf(stderr, _("Could not send cancel request: %s"), errbuf);
- }
- else
- CancelRequested = true;
-
- LeaveCriticalSection(&cancelConnLock);
-
- return TRUE;
- }
- else
- /* Return FALSE for any signals not being handled */
- return FALSE;
-}
-
-void
-setup_cancel_handler(void)
-{
- InitializeCriticalSection(&cancelConnLock);
-
- SetConsoleCtrlHandler(consoleHandler, TRUE);
-}
-
-#endif /* WIN32 */
diff --git a/src/bin/scripts/common.h b/src/bin/scripts/common.h
index b8580f927a..db2f85b472 100644
--- a/src/bin/scripts/common.h
+++ b/src/bin/scripts/common.h
@@ -10,6 +10,7 @@
#define COMMON_H
#include "common/username.h"
+#include "fe_utils/cancel.h"
#include "getopt_long.h" /* pgrminclude ignore */
#include "libpq-fe.h"
#include "pqexpbuffer.h" /* pgrminclude ignore */
@@ -60,10 +61,4 @@ extern void appendQualifiedRelation(PQExpBuffer buf, const char *name,
extern bool yesno_prompt(const char *question);
-extern void setup_cancel_handler(void);
-
-extern void SetCancelConn(PGconn *conn);
-extern void ResetCancelConn(void);
-
-
#endif /* COMMON_H */
diff --git a/src/bin/scripts/reindexdb.c b/src/bin/scripts/reindexdb.c
index f00aec15de..bedd95cf9d 100644
--- a/src/bin/scripts/reindexdb.c
+++ b/src/bin/scripts/reindexdb.c
@@ -187,7 +187,7 @@ main(int argc, char *argv[])
exit(1);
}
- setup_cancel_handler();
+ setup_cancel_handler(NULL);
if (alldb)
{
diff --git a/src/bin/scripts/vacuumdb.c b/src/bin/scripts/vacuumdb.c
index 2c7219239f..83a94dc632 100644
--- a/src/bin/scripts/vacuumdb.c
+++ b/src/bin/scripts/vacuumdb.c
@@ -257,7 +257,7 @@ main(int argc, char *argv[])
/* allow 'and_analyze' with 'analyze_only' */
}
- setup_cancel_handler();
+ setup_cancel_handler(NULL);
/* Avoid opening extra connections. */
if (tbl_count && (concurrentCons > tbl_count))
diff --git a/src/fe_utils/Makefile b/src/fe_utils/Makefile
index beea506536..e029333194 100644
--- a/src/fe_utils/Makefile
+++ b/src/fe_utils/Makefile
@@ -20,6 +20,7 @@ include $(top_builddir)/src/Makefile.global
override CPPFLAGS := -DFRONTEND -I$(libpq_srcdir) $(CPPFLAGS)
OBJS = \
+ cancel.o \
conditional.o \
mbprint.o \
print.o \
diff --git a/src/fe_utils/cancel.c b/src/fe_utils/cancel.c
new file mode 100644
index 0000000000..71d0911236
--- /dev/null
+++ b/src/fe_utils/cancel.c
@@ -0,0 +1,208 @@
+/*------------------------------------------------------------------------
+ *
+ * Query cancellation support for frontend code
+ *
+ * Assorted utility functions to control query cancellation with signal
+ * handler for SIGINT.
+ *
+ *
+ * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/fe-utils/cancel.c
+ *
+ *------------------------------------------------------------------------
+ */
+
+#include "postgres_fe.h"
+
+#include <signal.h>
+#include <unistd.h>
+
+#include "fe_utils/cancel.h"
+#include "fe_utils/connect.h"
+#include "fe_utils/string_utils.h"
+
+
+/*
+ * Write a simple string to stderr --- must be safe in a signal handler.
+ * We ignore the write() result since there's not much we could do about it.
+ * Certain compilers make that harder than it ought to be.
+ */
+#define write_stderr(str) \
+ do { \
+ const char *str_ = (str); \
+ int rc_; \
+ rc_ = write(fileno(stderr), str_, strlen(str_)); \
+ (void) rc_; \
+ } while (0)
+
+static PGcancel *volatile cancelConn = NULL;
+bool CancelRequested = false;
+
+#ifdef WIN32
+static CRITICAL_SECTION cancelConnLock;
+#endif
+
+/*
+ * SetCancelConn
+ *
+ * Set cancelConn to point to the current database connection.
+ */
+void
+SetCancelConn(PGconn *conn)
+{
+ PGcancel *oldCancelConn;
+
+#ifdef WIN32
+ EnterCriticalSection(&cancelConnLock);
+#endif
+
+ /* Free the old one if we have one */
+ oldCancelConn = cancelConn;
+ /* be sure handle_sigint doesn't use pointer while freeing */
+ cancelConn = NULL;
+
+ if (oldCancelConn != NULL)
+ PQfreeCancel(oldCancelConn);
+
+ cancelConn = PQgetCancel(conn);
+
+#ifdef WIN32
+ LeaveCriticalSection(&cancelConnLock);
+#endif
+}
+
+
+/*
+ * ResetCancelConn
+ *
+ * Free the current cancel connection, if any, and set to NULL.
+ */
+void
+ResetCancelConn(void)
+{
+ PGcancel *oldCancelConn;
+
+#ifdef WIN32
+ EnterCriticalSection(&cancelConnLock);
+#endif
+
+ oldCancelConn = cancelConn;
+ /* be sure handle_sigint doesn't use pointer while freeing */
+ cancelConn = NULL;
+
+ if (oldCancelConn != NULL)
+ PQfreeCancel(oldCancelConn);
+
+#ifdef WIN32
+ LeaveCriticalSection(&cancelConnLock);
+#endif
+}
+
+#ifndef WIN32
+/*
+ * Additional callback to handle interrupts
+ */
+static void (*sigint_callback)(void) = NULL;
+
+/*
+ * handle_sigint
+ *
+ * Handle interrupt signals by canceling the current command, if cancelConn
+ * is set.
+ */
+static void
+handle_sigint(SIGNAL_ARGS)
+{
+ int save_errno = errno;
+ char errbuf[256];
+
+ if (sigint_callback != NULL)
+ sigint_callback();
+
+ /* Send QueryCancel if we are processing a database query */
+ if (cancelConn != NULL)
+ {
+ if (PQcancel(cancelConn, errbuf, sizeof(errbuf)))
+ {
+ CancelRequested = true;
+ write_stderr(_("Cancel request sent\n"));
+ }
+ else
+ {
+ write_stderr(_("Could not send cancel request: "));
+ write_stderr(errbuf);
+ }
+ }
+ else
+ CancelRequested = true;
+
+ errno = save_errno; /* just in case the write changed it */
+}
+
+/*
+ * setup_cancel_handler
+ *
+ * Register query cancellation callback for SIGINT.
+ */
+void
+setup_cancel_handler(void (*callback)(void))
+{
+ sigint_callback = callback;
+ pqsignal(SIGINT, handle_sigint);
+}
+
+#else /* WIN32 */
+
+/*
+ * Console control handler for Win32. Note that the control handler will
+ * execute on a *different thread* than the main one, so we need to do
+ * proper locking around those structures.
+ */
+static BOOL WINAPI
+consoleHandler(DWORD dwCtrlType)
+{
+ char errbuf[256];
+
+ if (dwCtrlType == CTRL_C_EVENT ||
+ dwCtrlType == CTRL_BREAK_EVENT)
+ {
+ /* Send QueryCancel if we are processing a database query */
+ EnterCriticalSection(&cancelConnLock);
+ if (cancelConn != NULL)
+ {
+ if (PQcancel(cancelConn, errbuf, sizeof(errbuf)))
+ {
+ write_stderr(_("Cancel request sent\n"));
+ CancelRequested = true;
+ }
+ else
+ {
+ write_stderr(_("Could not send cancel request: %s"));
+ write_stderr(errbuf);
+ }
+ }
+ else
+ CancelRequested = true;
+
+ LeaveCriticalSection(&cancelConnLock);
+
+ return TRUE;
+ }
+ else
+ /* Return FALSE for any signals not being handled */
+ return FALSE;
+}
+
+void
+setup_cancel_handler(void *ignored)
+{
+ Assert(ignored == NULL);
+
+ InitializeCriticalSection(&cancelConnLock);
+
+ SetConsoleCtrlHandler(consoleHandler, TRUE);
+}
+
+#endif /* WIN32 */
diff --git a/src/include/fe_utils/cancel.h b/src/include/fe_utils/cancel.h
new file mode 100644
index 0000000000..cc199b7c8a
--- /dev/null
+++ b/src/include/fe_utils/cancel.h
@@ -0,0 +1,34 @@
+/*-------------------------------------------------------------------------
+ *
+ * Query cancellation support for frontend code
+ *
+ *
+ * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/fe_utils/cancel.h
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#ifndef CANCEL_H
+#define CANCEL_H
+
+#include "libpq-fe.h"
+
+extern bool CancelRequested;
+
+extern void SetCancelConn(PGconn *conn);
+extern void ResetCancelConn(void);
+
+#ifndef WIN32
+extern void setup_cancel_handler(void (*callback)(void));
+#else
+/*
+ * Ensure that the signature is the same under windows, at the price of
+ * ignoring the function parameter.
+ */
+extern void setup_cancel_handler(void *ignored);
+#endif /* WIN32 */
+
+#endif /* CANCEL_H */
diff --git a/src/tools/msvc/Mkvcbuild.pm b/src/tools/msvc/Mkvcbuild.pm
index 9a0963a050..afa29b5ff8 100644
--- a/src/tools/msvc/Mkvcbuild.pm
+++ b/src/tools/msvc/Mkvcbuild.pm
@@ -142,7 +142,7 @@ sub mkvcbuild
our @pgcommonbkndfiles = @pgcommonallfiles;
our @pgfeutilsfiles = qw(
- conditional.c mbprint.c print.c psqlscan.l psqlscan.c
+ cancel.c conditional.c mbprint.c print.c psqlscan.l psqlscan.c
simple_list.c string_utils.c recovery_gen.c);
$libpgport = $solution->AddProject('libpgport', 'lib', 'misc');
