Merge pull request #3 from firefly-zero/stash

Stash: load_stash, save_stash, BEFORE_EXIT

Author: orsinium

src/firefly.c

@@ -250,6 +250,34 @@ bool is_online(Peers peers, Peer peer)
     return ((peers.online >> peer) & 1) != 0;
 }
 
+/// @brief Save the given Stash.
+///
+/// @details When called, the stash for the given peer will be stored in RAM.
+/// Calling load_stash() for the same peer will return that stash.
+/// On exit, the runtime will persist the stash in FS.
+/// Next time the app starts, calling load_stash() will restore the stash
+/// saved earlier.
+void save_stash(Peer p, Stash s)
+{
+    _ffb_save_stash(p, (int)s.head, s.size);
+}
+
+/// @brief Load Stash saved earlier (in this or previous run) by save_stash.
+///
+/// @details The buffer should be big enough to fit the stash.
+/// If it's not, the stash will be truncated.
+/// If there is no stash or it's empty, nil is returned.
+///
+/// If the given buffer is nil, a new buffer will be allocated
+/// big enough to fit the biggest allowed stash. At the moment, it is 80 bytes.
+Stash load_stash(Peer p, Buffer s)
+{
+    Stash res;
+    res.size = _ffb_load_stash(p, (int)s.head, s.size);
+    res.head = s.head;
+    return res;
+}
+
 // -- MISC -- //
 
 /// @brief Write a debug message.

src/firefly.h

@@ -19,6 +19,9 @@
 /// @brief Mark a "cheat" callback function.
 #define CHEAT __attribute__((export_name("cheat")))
 
+/// @brief Mark a "before_exit" callback function.
+#define BEFORE_EXIT __attribute__((export_name("BEFORE_EXIT")))
+
 /// @brief Screen width.
 #define WIDTH 240
 /// @brief Screen height.
@@ -152,6 +155,7 @@ typedef struct Buffer Buffer;
 typedef struct Buffer File;
 typedef struct Buffer Image;
 typedef struct Buffer Canvas;
+typedef struct Buffer Stash;
 
 /// @brief A subregion of an Image.
 struct SubImage
@@ -378,6 +382,8 @@ void remove_file(char *path);
 Peer get_me();
 Peers get_peers();
 bool is_online(Peers peers, Peer peer);
+void save_stash(Peer p, Stash s);
+Stash load_stash(Peer p, Buffer s);
 
 void log_debug(char *msg);
 void log_error(char *msg);

src/firefly_bindings.h

@@ -81,12 +81,18 @@ void _ffb_remove_file(uintptr_t pathPtr, uintptr_t pathLen);
 
 // -- NET -- //
 
-WASM_IMPORT("misc", "get_me")
+WASM_IMPORT("net", "get_me")
 int32_t _ffb_get_me();
 
-WASM_IMPORT("misc", "get_peers")
+WASM_IMPORT("net", "get_peers")
 int32_t _ffb_get_peers();
 
+WASM_IMPORT("net", "save_stash")
+_ffb_save_stash(uintptr_t peerID, uintptr_t bufPtr, uintptr_t bufLen);
+
+WASM_IMPORT("net", "load_stash")
+int32_t _ffb_load_stash(uintptr_t peerID, uintptr_t bufPtr, uintptr_t bufLen);
+
 // -- STATS -- //
 
 WASM_IMPORT("misc", "add_progress")