#include "commands/defrem.h"
#include "commands/explain.h"
#include "commands/explain_state.h"
+#include "utils/builtins.h"
+#include "utils/guc.h"
/* Hook to perform additional EXPLAIN options validation */
explain_validate_options_hook_type explain_validate_options_hook = NULL;
{
const char *option_name;
ExplainOptionHandler option_handler;
+ ExplainOptionGUCCheckHandler guc_check_handler;
} ExplainExtensionOption;
static const char **ExplainExtensionNameArray = NULL;
/*
* Register a new EXPLAIN option.
*
+ * option_name is assumed to be a constant string or allocated in storage
+ * that will never be freed.
+ *
* When option_name is used as an EXPLAIN option, handler will be called and
* should update the ExplainState passed to it. See comments at top of file
* for a more detailed explanation.
*
- * option_name is assumed to be a constant string or allocated in storage
- * that will never be freed.
+ * guc_check_handler is a function that can be safely called from a
+ * GUC check hook to validate a proposed value for a custom EXPLAIN option.
+ * Boolean-valued options can pass GUCCheckBooleanExplainOption. See the
+ * comments for GUCCheckBooleanExplainOption for further information on
+ * how a guc_check_handler should behave.
*/
void
RegisterExtensionExplainOption(const char *option_name,
- ExplainOptionHandler handler)
+ ExplainOptionHandler handler,
+ ExplainOptionGUCCheckHandler guc_check_handler)
{
ExplainExtensionOption *exopt;
+ Assert(handler != NULL);
+ Assert(guc_check_handler != NULL);
+
/* Search for an existing option by this name; if found, update handler. */
for (int i = 0; i < ExplainExtensionOptionsAssigned; ++i)
{
if (strcmp(ExplainExtensionOptionArray[i].option_name,
option_name) == 0)
{
- ExplainExtensionOptionArray[i].option_handler = handler;
+ exopt = &ExplainExtensionOptionArray[i];
+
+ exopt->option_handler = handler;
+ exopt->guc_check_handler = guc_check_handler;
return;
}
}
exopt = &ExplainExtensionOptionArray[ExplainExtensionOptionsAssigned++];
exopt->option_name = option_name;
exopt->option_handler = handler;
+ exopt->guc_check_handler = guc_check_handler;
}
/*
return false;
}
+
+/*
+ * Determine whether an EXPLAIN extension option will be accepted without
+ * error. Returns true if so, and false if not. See the comments for
+ * GUCCheckBooleanExplainOption for more details.
+ *
+ * The caller need not know that the option_name is valid; this function
+ * will indicate that the option is unrecognized if that is the case.
+ */
+bool
+GUCCheckExplainExtensionOption(const char *option_name,
+ const char *option_value,
+ NodeTag option_type)
+{
+ for (int i = 0; i < ExplainExtensionOptionsAssigned; i++)
+ {
+ ExplainExtensionOption *exopt = &ExplainExtensionOptionArray[i];
+
+ if (strcmp(exopt->option_name, option_name) == 0)
+ return exopt->guc_check_handler(option_name, option_value,
+ option_type);
+ }
+
+ /* Unrecognized option name. */
+ GUC_check_errmsg("unrecognized EXPLAIN option \"%s\"", option_name);
+ return false;
+}
+
+/*
+ * guc_check_handler for Boolean-valued EXPLAIN extension options.
+ *
+ * After receiving a "true" value from this or any other GUC check handler
+ * for an EXPLAIN extension option, the caller is entitled to assume that
+ * a suitably constructed DefElem passed to the main option handler will
+ * not cause an error. To construct this DefElem, the caller should set
+ * the DefElem's defname to option_name. If option_values is NULL, arg
+ * should be NULL. Otherwise, arg should be of the type given by
+ * option_type, with option_value as the associated value. The only option
+ * types that should be passed are T_String, T_Float, and T_Integer; in
+ * the last case, the caller will need to perform a string-to-integer
+ * conversion.
+ *
+ * A guc_check_handler should not throw an error, and should not allocate
+ * memory. If it returns false to indicate that the option_value is not
+ * acceptable, it may use GUC_check_errmsg(), GUC_check_errdetail(), etc.
+ * to clarify the nature of the problem.
+ *
+ * Since we're concerned with Boolean options here, the logic below must
+ * exactly match the semantics of defGetBoolean.
+ */
+bool
+GUCCheckBooleanExplainOption(const char *option_name,
+ const char *option_value,
+ NodeTag option_type)
+{
+ bool valid = false;
+
+ if (option_value == NULL)
+ {
+ /* defGetBoolean treats no argument as valid */
+ valid = true;
+ }
+ else if (option_type == T_String)
+ {
+ /* defGetBoolean accepts exactly these string values */
+ if (pg_strcasecmp(option_value, "true") == 0 ||
+ pg_strcasecmp(option_value, "false") == 0 ||
+ pg_strcasecmp(option_value, "on") == 0 ||
+ pg_strcasecmp(option_value, "off") == 0)
+ valid = true;
+ }
+ else if (option_type == T_Integer)
+ {
+ long value;
+ char *end;
+
+ /*
+ * defGetBoolean accepts only 0 and 1, but those can be spelled in
+ * various ways (e.g. 01, 0x01).
+ */
+ errno = 0;
+ value = strtol(option_value, &end, 0);
+ if (errno == 0 && *end == '\0' && end != option_value &&
+ value == (int) value && (value == 0 || value == 1))
+ valid = true;
+ }
+
+ if (!valid)
+ {
+ GUC_check_errmsg("EXPLAIN option \"%s\" requires a Boolean value",
+ option_name);
+ return false;
+ }
+
+ return true;
+}
} ExplainState;
typedef void (*ExplainOptionHandler) (ExplainState *, DefElem *, ParseState *);
+typedef bool (*ExplainOptionGUCCheckHandler) (const char *option_name,
+ const char *option_value,
+ NodeTag option_type);
/* Hook to perform additional EXPLAIN options validation */
typedef void (*explain_validate_options_hook_type) (ExplainState *es, List *options,
void *opaque);
extern void RegisterExtensionExplainOption(const char *option_name,
- ExplainOptionHandler handler);
+ ExplainOptionHandler handler,
+ ExplainOptionGUCCheckHandler guc_check_handler);
extern bool ApplyExtensionExplainOption(ExplainState *es, DefElem *opt,
ParseState *pstate);
+extern bool GUCCheckExplainExtensionOption(const char *option_name,
+ const char *option_value,
+ NodeTag option_type);
+
+extern bool GUCCheckBooleanExplainOption(const char *option_name,
+ const char *option_value,
+ NodeTag option_type);
#endif /* EXPLAIN_STATE_H */
projects / thirdparty / postgresql.git / commitdiff
