Add plugin dependencies

diff --git a/README.md b/README.md
index 1f554cd4076b43bb166f6ff2f99f3c1112548a43..712f5ebbc05a60920eb5867472bbbd102c49848e 100644 (file)
--- a/README.md
+++ b/README.md
@@ -6,7 +6,7 @@ You might want to include the game.h file from plugins/game/game.h. Have a look
 
 Controls: WASD to move, Q to quit.
 
-To build the loader and the plugins in the plugins/ folder, simply type `make` or `make all`. There are separate targets for the loader (`dungeon`) and the plugins. All Makefiles that are placed in plugin directories, so you might want to include a makefile in your plugin. The plugins target simply depends on ${PLUGINS}, so just add things to this in your plugin Makefile to add them to the plugins target (usually your plugin.so) 
+To build the loader and the plugins in the plugins/ folder, simply type `make` or `make all`. There are separate targets for the loader (`dungeon`) and the plugins. All Makefiles that are placed in plugin directories, so you might want to include a makefile in your plugin. The plugins target simply depends on ${PLUGINS}, so just add things to this in your plugin Makefile to add them to the plugins target (usually your plugin.so)
 To run the loader, type `./dungeon`. It will load all plugins including the game itself dynamically and run the game.
 
-Plugins are loaded in alphabethical order, with the exception of the game plugin that is loaded first. If you want to make a plugin that depends on another plugin, make sure the other plugin is loaded first by setting the name of your plugin accordingly. A cleaner solution to this is coming soon.
+If you want to make a plugin that depends on another plugin (including the game itself), make sure to depend on that plugin. To add dependencies to a plugin, create a file named dependencies.txt in the plugin folder. Put the names of all plugins your plugin depends on into that file. You can use spaces or newlines as seperators.

diff --git a/dungeon.c b/dungeon.c
index a1b00645a8b580f3d6f8e714f12bad09bbebf12c..d461d641b6854d4ce2e4782b230faa3ce2b90be6 100644 (file)
--- a/dungeon.c
+++ b/dungeon.c
@@ -5,20 +5,63 @@
 #include <dirent.h>
 #include <string.h>
 
+struct plugin_list
+{
+       char *name;
+       void *handle;
+       struct plugin_list *next;
+};
+
+struct plugin_list *plugins = NULL;
+struct plugin_list **next = &plugins;
+
 static void *load_plugin(const char *name)
 {
+       for (struct plugin_list *ptr = plugins; ptr != NULL; ptr = ptr->next) {
+               if (strcmp(ptr->name, name) == 0)
+                       return ptr->handle;
+       }
+
        size_t len = strlen(name);
-       char filename[1 + 1 + 7 + 1 + len + 1 + len + 1 + 2 + 1];
-       sprintf(filename, "./plugins/%s/%s.so", name, name);
 
-       void *plugin_handle = dlmopen(LM_ID_BASE, filename, RTLD_NOW | RTLD_GLOBAL);
+       char dependency_file_name[1 + 1 + 7 + 1 + len + 1 + 12 + 1 + 3 + 1];
+       sprintf(dependency_file_name, "./plugins/%s/dependencies.txt", name);
+
+       FILE *dependency_file = fopen(dependency_file_name, "r");
+
+       if (dependency_file) {
+               char dependency[BUFSIZ];
+
+               while (fscanf(dependency_file, "%s", dependency) != EOF)
+                       load_plugin(dependency);
 
-       if (! plugin_handle) {
+               fclose(dependency_file);
+       }
+
+       char library_name[1 + 1 + 7 + 1 + len + 1 + len + 1 + 2 + 1];
+       sprintf(library_name, "./plugins/%s/%s.so", name, name);
+
+       void *handle = dlmopen(LM_ID_BASE, library_name, RTLD_NOW | RTLD_GLOBAL);
+
+       if (! handle) {
                printf("%s\n", dlerror());
                exit(EXIT_FAILURE);
        }
 
-       return plugin_handle;
+       char *namebuf = malloc(len + 1);
+       strcpy(namebuf, name);
+
+       *next = malloc(sizeof(struct plugin_list));
+       **next = (struct plugin_list) {
+               .name = namebuf,
+               .handle = handle,
+               .next = NULL,
+       };
+       next = &(*next)->next;
+
+       printf("Loaded %s\n", name);
+
+       return handle;
 }
 
 int main()
@@ -30,11 +73,9 @@ int main()
 
        struct dirent *dp;
 
-       while (dp = readdir(dir)) {
-               if (dp->d_name[0] != '.' && strcmp(dp->d_name, "game") != 0) {
+       while (dp = readdir(dir))
+               if (dp->d_name[0] != '.')
                        load_plugin(dp->d_name);
-               }
-       }
 
        closedir(dir);
 

diff --git a/plugins/apple/dependencies.txt b/plugins/apple/dependencies.txt
new file mode 100644 (file)
index 0000000..dc22e61
--- /dev/null
+++ b/plugins/apple/dependencies.txt
@@ -0,0 +1 @@
+game

diff --git a/plugins/fireball/dependencies.txt b/plugins/fireball/dependencies.txt
new file mode 100644 (file)
index 0000000..dc22e61
--- /dev/null
+++ b/plugins/fireball/dependencies.txt
@@ -0,0 +1 @@
+game

diff --git a/plugins/monster/dependencies.txt b/plugins/monster/dependencies.txt
new file mode 100644 (file)
index 0000000..dc22e61
--- /dev/null
+++ b/plugins/monster/dependencies.txt
@@ -0,0 +1 @@
+game

diff --git a/plugins/movement/dependencies.txt b/plugins/movement/dependencies.txt
new file mode 100644 (file)
index 0000000..dc22e61
--- /dev/null
+++ b/plugins/movement/dependencies.txt
@@ -0,0 +1 @@
+game