forked from soreau/weston
-
Notifications
You must be signed in to change notification settings - Fork 1
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Implement a simple register and lookup for function tables. This is intended for plugins to expose APIs to other plugins. It has been very hard to arrange a plugin to be able to call into another plugin without modifying Weston core to explicitly support each case. This patch fixes that. The tests all pass. Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
- Loading branch information
Showing
6 changed files
with
328 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,156 @@ | ||
/* | ||
* Copyright (C) 2016 DENSO CORPORATION | ||
* | ||
* Permission is hereby granted, free of charge, to any person obtaining | ||
* a copy of this software and associated documentation files (the | ||
* "Software"), to deal in the Software without restriction, including | ||
* without limitation the rights to use, copy, modify, merge, publish, | ||
* distribute, sublicense, and/or sell copies of the Software, and to | ||
* permit persons to whom the Software is furnished to do so, subject to | ||
* the following conditions: | ||
* | ||
* The above copyright notice and this permission notice (including the | ||
* next paragraph) shall be included in all copies or substantial | ||
* portions of the Software. | ||
* | ||
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, | ||
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF | ||
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND | ||
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS | ||
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN | ||
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN | ||
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE | ||
* SOFTWARE. | ||
*/ | ||
|
||
#include "config.h" | ||
|
||
#include <assert.h> | ||
#include <string.h> | ||
#include <stdlib.h> | ||
|
||
#include "compositor.h" | ||
#include "plugin-registry.h" | ||
|
||
struct weston_plugin_api { | ||
struct wl_list link; /**< in weston_compositor::plugin_api_list */ | ||
|
||
char *api_name; /**< The search key */ | ||
const void *vtable; /**< The function table */ | ||
size_t vtable_size; /**< Size of the function table in bytes */ | ||
}; | ||
|
||
/** Register an implementation of an API | ||
* | ||
* \param compositor The compositor instance. | ||
* \param api_name The API name which other plugins use to find the | ||
* implementation. | ||
* \param vtable Pointer to the function table of the API. | ||
* \param vtable_size Size of the function table in bytes. | ||
* \return 0 on success, -1 on error, -2 if api_name already registered | ||
* | ||
* This call makes the given vtable to be reachable via | ||
* weston_plugin_api_get(). Calls through the vtable may start happening | ||
* as soon as the caller returns after success. Argument vtable must not be | ||
* NULL. Argument api_name must be non-NULL and non-zero length. | ||
* | ||
* You can increase the function table size without breaking the ABI. | ||
* To cater for ABI breaks, it is recommended to have api_name include a | ||
* version number. | ||
* | ||
* A registered API cannot be unregistered. However, calls through a | ||
* registered API must not be made from the compositor destroy signal handlers. | ||
*/ | ||
WL_EXPORT int | ||
weston_plugin_api_register(struct weston_compositor *compositor, | ||
const char *api_name, | ||
const void *vtable, | ||
size_t vtable_size) | ||
{ | ||
struct weston_plugin_api *wpa; | ||
|
||
assert(api_name); | ||
assert(strlen(api_name) > 0); | ||
assert(vtable); | ||
|
||
if (!api_name || !vtable || strlen(api_name) == 0) | ||
return -1; | ||
|
||
wl_list_for_each(wpa, &compositor->plugin_api_list, link) | ||
if (strcmp(wpa->api_name, api_name) == 0) | ||
return -2; | ||
|
||
wpa = zalloc(sizeof(*wpa)); | ||
if (!wpa) | ||
return -1; | ||
|
||
wpa->api_name = strdup(api_name); | ||
wpa->vtable = vtable; | ||
wpa->vtable_size = vtable_size; | ||
|
||
if (!wpa->api_name) { | ||
free(wpa); | ||
|
||
return -1; | ||
} | ||
|
||
wl_list_insert(&compositor->plugin_api_list, &wpa->link); | ||
weston_log("Registered plugin API '%s' of size %zd\n", | ||
wpa->api_name, wpa->vtable_size); | ||
|
||
return 0; | ||
} | ||
|
||
/** Internal function to free registered APIs | ||
* | ||
* \param compositor The compositor instance. | ||
*/ | ||
void | ||
weston_plugin_api_destroy_list(struct weston_compositor *compositor) | ||
{ | ||
struct weston_plugin_api *wpa, *tmp; | ||
|
||
wl_list_for_each_safe(wpa, tmp, &compositor->plugin_api_list, link) { | ||
free(wpa->api_name); | ||
wl_list_remove(&wpa->link); | ||
free(wpa); | ||
} | ||
} | ||
|
||
/** Fetch the implementation of an API | ||
* | ||
* \param compositor The compositor instance. | ||
* \param api_name The name of the API to search for. | ||
* \param vtable_size The expected function table size in bytes. | ||
* \return Pointer to the function table, or NULL on error. | ||
* | ||
* Find the function table corresponding to api_name. The vtable_size here | ||
* must be less or equal to the vtable_size given in the corresponding | ||
* weston_plugin_api_register() call made by the implementing plugin. | ||
* | ||
* Calls can be made through the function table immediately. However, calls | ||
* must not be made from or after the compositor destroy signal handler. | ||
*/ | ||
WL_EXPORT const void * | ||
weston_plugin_api_get(struct weston_compositor *compositor, | ||
const char *api_name, | ||
size_t vtable_size) | ||
{ | ||
struct weston_plugin_api *wpa; | ||
|
||
assert(api_name); | ||
if (!api_name) | ||
return NULL; | ||
|
||
wl_list_for_each(wpa, &compositor->plugin_api_list, link) { | ||
if (strcmp(wpa->api_name, api_name) != 0) | ||
continue; | ||
|
||
if (vtable_size <= wpa->vtable_size) | ||
return wpa->vtable; | ||
|
||
return NULL; | ||
} | ||
|
||
return NULL; | ||
} |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,55 @@ | ||
/* | ||
* Copyright (C) 2016 DENSO CORPORATION | ||
* | ||
* Permission is hereby granted, free of charge, to any person obtaining | ||
* a copy of this software and associated documentation files (the | ||
* "Software"), to deal in the Software without restriction, including | ||
* without limitation the rights to use, copy, modify, merge, publish, | ||
* distribute, sublicense, and/or sell copies of the Software, and to | ||
* permit persons to whom the Software is furnished to do so, subject to | ||
* the following conditions: | ||
* | ||
* The above copyright notice and this permission notice (including the | ||
* next paragraph) shall be included in all copies or substantial | ||
* portions of the Software. | ||
* | ||
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, | ||
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF | ||
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND | ||
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS | ||
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN | ||
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN | ||
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE | ||
* SOFTWARE. | ||
*/ | ||
|
||
#ifndef WESTON_PLUGIN_REGISTRY_H | ||
#define WESTON_PLUGIN_REGISTRY_H | ||
|
||
#include <stddef.h> | ||
|
||
#ifdef __cplusplus | ||
extern "C" { | ||
#endif | ||
|
||
struct weston_compositor; | ||
|
||
int | ||
weston_plugin_api_register(struct weston_compositor *compositor, | ||
const char *api_name, | ||
const void *vtable, | ||
size_t vtable_size); | ||
|
||
const void * | ||
weston_plugin_api_get(struct weston_compositor *compositor, | ||
const char *api_name, | ||
size_t vtable_size); | ||
|
||
void | ||
weston_plugin_api_destroy_list(struct weston_compositor *compositor); | ||
|
||
#ifdef __cplusplus | ||
} | ||
#endif | ||
|
||
#endif /* WESTON_PLUGIN_REGISTRY_H */ |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,101 @@ | ||
/* | ||
* Copyright (C) 2016 DENSO CORPORATION | ||
* | ||
* Permission is hereby granted, free of charge, to any person obtaining | ||
* a copy of this software and associated documentation files (the | ||
* "Software"), to deal in the Software without restriction, including | ||
* without limitation the rights to use, copy, modify, merge, publish, | ||
* distribute, sublicense, and/or sell copies of the Software, and to | ||
* permit persons to whom the Software is furnished to do so, subject to | ||
* the following conditions: | ||
* | ||
* The above copyright notice and this permission notice (including the | ||
* next paragraph) shall be included in all copies or substantial | ||
* portions of the Software. | ||
* | ||
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, | ||
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF | ||
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND | ||
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS | ||
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN | ||
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN | ||
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE | ||
* SOFTWARE. | ||
*/ | ||
|
||
#include "config.h" | ||
|
||
#include <assert.h> | ||
|
||
#include "compositor.h" | ||
#include "plugin-registry.h" | ||
|
||
static void | ||
dummy_func(void) | ||
{ | ||
} | ||
|
||
static const struct my_api { | ||
void (*func1)(void); | ||
void (*func2)(void); | ||
void (*func3)(void); | ||
} my_test_api = { | ||
dummy_func, | ||
dummy_func, | ||
dummy_func, | ||
}; | ||
|
||
#define MY_API_NAME "test_my_api_v1" | ||
|
||
static void | ||
init_tests(struct weston_compositor *compositor) | ||
{ | ||
assert(weston_plugin_api_get(compositor, MY_API_NAME, | ||
sizeof(my_test_api)) == NULL); | ||
|
||
assert(weston_plugin_api_register(compositor, MY_API_NAME, &my_test_api, | ||
sizeof(my_test_api)) == 0); | ||
|
||
assert(weston_plugin_api_register(compositor, MY_API_NAME, &my_test_api, | ||
sizeof(my_test_api)) == -2); | ||
|
||
assert(weston_plugin_api_get(compositor, MY_API_NAME, | ||
sizeof(my_test_api)) == &my_test_api); | ||
|
||
assert(weston_plugin_api_register(compositor, "another", &my_test_api, | ||
sizeof(my_test_api)) == 0); | ||
} | ||
|
||
static void | ||
runtime_tests(void *data) | ||
{ | ||
struct weston_compositor *compositor = data; | ||
const struct my_api *api; | ||
size_t sz = sizeof(struct my_api); | ||
|
||
assert(weston_plugin_api_get(compositor, MY_API_NAME, sz) == | ||
&my_test_api); | ||
|
||
assert(weston_plugin_api_get(compositor, MY_API_NAME, sz - 4) == | ||
&my_test_api); | ||
|
||
assert(weston_plugin_api_get(compositor, MY_API_NAME, sz + 4) == NULL); | ||
|
||
api = weston_plugin_api_get(compositor, MY_API_NAME, sz); | ||
assert(api && api->func2 == dummy_func); | ||
|
||
wl_display_terminate(compositor->wl_display); | ||
} | ||
|
||
WL_EXPORT int | ||
module_init(struct weston_compositor *compositor, int *argc, char *argv[]) | ||
{ | ||
struct wl_event_loop *loop; | ||
|
||
init_tests(compositor); | ||
|
||
loop = wl_display_get_event_loop(compositor->wl_display); | ||
wl_event_loop_add_idle(loop, runtime_tests, compositor); | ||
|
||
return 0; | ||
} |