From 1c3935d040d00ce55fa565603ade7b011b0cd88e Mon Sep 17 00:00:00 2001
From: sup39 <sms@sup39.dev>
Date: Wed, 9 Nov 2022 21:51:50 +0900
Subject: [PATCH] init

---
 LICENSE     | 24 +++++++++++++++++++++++
 README.md   |  7 +++++++
 ReadFile.c  | 56 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 ReadFile.ld |  4 ++++
 4 files changed, 91 insertions(+)
 create mode 100644 LICENSE
 create mode 100644 README.md
 create mode 100644 ReadFile.c
 create mode 100644 ReadFile.ld

diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..ae591eb
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,24 @@
+MIT License
+
+Copyright (c) 2022 sup39
+
+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 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.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..a2b987c
--- /dev/null
+++ b/README.md
@@ -0,0 +1,7 @@
+# Read File
+Read file from memory card in SMS without allocating memory or modifying game id
+
+## TODO
+- [ ] Add error message
+- [ ] Handle inserting/removing memory card
+- [ ] Make sure there is no side effect
diff --git a/ReadFile.c b/ReadFile.c
new file mode 100644
index 0000000..92c756a
--- /dev/null
+++ b/ReadFile.c
@@ -0,0 +1,56 @@
+typedef struct {
+  char pad[20];
+} CARDFileInfo;
+typedef struct {
+  int slot;
+} TCardManager;
+
+/** For NTSC-J 1.0:
+ *
+ * mount_    80107b50
+ * open_     801072f4
+ * CARDOpen  800a3cac
+ * CARDRead  800a4640
+ * CARDClose 800a3e24
+ *
+ * onReadOptionBlock 801069f4
+ */
+
+typedef int bool;
+int mount_(TCardManager *this, bool);
+int open_(TCardManager *this, CARDFileInfo*);
+int CARDOpen(int slot, const char *fileName, CARDFileInfo*);
+int CARDRead(CARDFileInfo *fileInfo, void *buf, unsigned long size, unsigned long offset);
+int CARDClose(CARDFileInfo *fileInfo);
+
+#define fileName "gct"
+#define dst ((void*)0x817F0000)
+#define size 0xE000 // 7 blocks
+int onReadOptionBlock(TCardManager *this, CARDFileInfo *fileInfo) {
+  int rc;
+  // mount
+  if ((rc = mount_(this, 1))) goto orig;
+
+  // open file
+  if ((rc = CARDOpen(this->slot, fileName, fileInfo))) {
+    // TODO error handling
+    // if (rc == -4) // file not exists
+    goto orig;
+  }
+
+  // read file to memory
+  if ((rc = CARDRead(fileInfo, dst, size, 0))) {
+    // should not fail if (dst, size) is properly set
+  } else {
+    // everything is good
+    // TODO apply gecko code
+    *(char*)0x817effff = 1; // ready (temporary solution)
+  }
+
+  // close file
+  CARDClose(fileInfo);
+
+orig:
+  // original function call 
+  return open_(this, fileInfo);
+}
diff --git a/ReadFile.ld b/ReadFile.ld
new file mode 100644
index 0000000..198acd1
--- /dev/null
+++ b/ReadFile.ld
@@ -0,0 +1,4 @@
+$$ = 0x817eff00;
+
+/* TCardManager::cmdLoop() */
+$bl$onReadOptionBlock = 0x801069f4;