Merge branch 'wip-cache' into 'master'

Reduce requests to underlying API

Closes openpaperwork#1

See merge request World/OpenPaperwork/libinsane!6

Author: Thomas Perret

subprojects/libinsane/include/libinsane/dumb.h

@@ -29,7 +29,7 @@ void lis_dumb_set_list_devices_return(struct lis_api *self, enum lis_error ret);
 void lis_dumb_set_get_device_return(struct lis_api *self, enum lis_error ret);
 
 void lis_dumb_add_option(struct lis_api *self, const struct lis_option_descriptor *opt,
-	const union lis_value *default_value);
+	const union lis_value *default_value, int set_flags);
 
 struct lis_dumb_read {
 	const void *content;
@@ -45,6 +45,8 @@ void lis_dumb_set_scan_result(
 );
 int lis_dumb_get_nb_get(struct lis_api *self);
 int lis_dumb_get_nb_set(struct lis_api *self);
+int lis_dumb_get_nb_list_options(struct lis_api *self);
+
 
 #ifdef __cplusplus
 }

subprojects/libinsane/include/libinsane/workarounds.h

@@ -172,6 +172,26 @@ extern enum lis_error lis_api_workaround_one_page_flatbed(
 	struct lis_api *to_wrap, struct lis_api **out_impl
 );
 
+
+/*!
+ * \brief Minimize calls to underlying API
+ *
+ * - API: Sane (maybe others)
+ * - Culprit: HP drivers + sane backend 'net' (+ difference of versions
+ *   between servers and clients) (maybe
+ *   others)
+ *
+ * Some drivers or combinations of drivers seem to be very touchy. This
+ * workaround aim to reduce to a strict minimum all the calls to
+ * list_options(), option->fn.set(), option->fn.get().
+ *
+ * Assumes that the 'set_fllags' when calling option->fn.set() is reliable.
+ */
+extern enum lis_error lis_api_workaround_cache(
+	struct lis_api *to_wrap, struct lis_api **out_impl
+);
+
+
 #ifdef __cplusplus
 }
 #endif

subprojects/libinsane/src/bases/dumb.c

@@ -16,6 +16,7 @@
 struct lis_dumb_option {
 	struct lis_option_descriptor parent;
 	struct lis_dumb_private *impl;
+	int set_flags;
 
 	int has_value;
 	union lis_value default_value;
@@ -62,6 +63,7 @@ struct lis_dumb_private {
 	} scan;
 
 	struct {
+		int list;
 		int set;
 		int get;
 	} nb;
@@ -270,7 +272,7 @@ static enum lis_error dumb_opt_set_value(struct lis_option_descriptor *self,
 	lis_copy(self->value.type, &value, &private->value);
 	private->has_value = 1;
 
-	*set_flags = LIS_SET_FLAG_MUST_RELOAD_PARAMS;
+	*set_flags = private->set_flags;
 	return LIS_OK;
 }
 
@@ -280,6 +282,7 @@ static enum lis_error dumb_get_options(
 	)
 {
 	struct lis_dumb_item *private = LIS_DUMB_ITEM(self);
+	private->impl->nb.list++;
 	*out_descs = private->impl->opts;
 	return LIS_OK;
 }
@@ -406,7 +409,7 @@ void lis_dumb_set_get_device_return(struct lis_api *self, enum lis_error ret)
 
 
 void lis_dumb_add_option(struct lis_api *self, const struct lis_option_descriptor *opt,
-	const union lis_value *default_value)
+	const union lis_value *default_value, int set_flags)
 {
 
 	struct lis_dumb_private *private = LIS_DUMB_PRIVATE(self);
@@ -415,6 +418,7 @@ void lis_dumb_add_option(struct lis_api *self, const struct lis_option_descripto
 
 	opt_private = calloc(1, sizeof(struct lis_dumb_option));
 	opt_private->impl = private;
+	opt_private->set_flags = set_flags;
 	memcpy(&opt_private->parent, opt, sizeof(opt_private->parent));
 	if (opt_private->parent.fn.get_value == NULL) {
 		opt_private->parent.fn.get_value = dumb_opt_get_value;
@@ -523,3 +527,10 @@ int lis_dumb_get_nb_set(struct lis_api *self)
 	struct lis_dumb_private *private = LIS_DUMB_PRIVATE(self);
 	return private->nb.set;
 }
+
+
+int lis_dumb_get_nb_list_options(struct lis_api *self)
+{
+	struct lis_dumb_private *private = LIS_DUMB_PRIVATE(self);
+	return private->nb.list;
+}

subprojects/libinsane/src/meson.build

@@ -21,6 +21,7 @@ libinsane_srcs = files(
     'safebet.c',
     'str2impls.c',
     'util.c',
+    'workarounds/cache.c',
     'workarounds/check_capabilities.c',
     'workarounds/dedicated_thread.c',
     'workarounds/one_page_flatbed.c',

subprojects/libinsane/src/safebet.c

@@ -39,6 +39,12 @@ static const struct {
 		.wrap_cb = lis_api_workaround_check_capabilities,
 		.enabled_by_default = 1,
 	},
+	{
+		.name = "workaround_cache",
+		.env = "LIBINSANE_WORKAROUND_CACHE",
+		.wrap_cb = lis_api_workaround_cache,
+		.enabled_by_default = 1,
+	},
 	{
 		.name = "normalizer_source_nodes",
 		.env = "LIBINSANE_NORMALIZER_SOURCE_NODES",

subprojects/libinsane/src/str2impls.c

@@ -101,6 +101,8 @@ enum lis_error lis_str2impls(const char *list_of_impls, struct lis_api **impls)
 				err = lis_api_workaround_opt_values(*impls, &next);
 			} else if (strcmp(tok, "one_page_flatbed") == 0) {
 				err = lis_api_workaround_one_page_flatbed(*impls, &next);
+			} else if (strcmp(tok, "cache") == 0) {
+				err = lis_api_workaround_cache(*impls, &next);
 			} else {
 				lis_log_error("Unknown API wrapper: %s", tok);
 				err = LIS_ERR_INTERNAL_NOT_IMPLEMENTED;
@@ -109,7 +111,7 @@ enum lis_error lis_str2impls(const char *list_of_impls, struct lis_api **impls)
 		}
 
 		if (LIS_IS_ERROR(err)) {
-			lis_log_error("Failed to instanciate API implementation '%s'", tok);
+			lis_log_error("Failed to instantiate API implementation '%s'", tok);
 			goto error;
 		}