lxfs: implemented opendir()

fs/lxfs/src/dirent.c

@@ -0,0 +1,54 @@
+/*
+ * luxOS - a unix-like operating system
+ * Omar Elghoul, 2024
+ * 
+ * lxfs: Driver for the lxfs file system
+ */
+
+#include <liblux/liblux.h>
+#include <lxfs/lxfs.h>
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+
+/* lxfsOpendir(): opens a directory on an lxfs volume
+ * params: ocmd - open directory command message
+ * returns: nothing, response relayed to vfs
+ */
+
+void lxfsOpendir(OpendirCommand *ocmd) {
+    ocmd->header.header.response = 1;
+    ocmd->header.header.length = sizeof(OpenCommand);
+
+    Mountpoint *mp = findMP(ocmd->device);
+    if(!mp) {
+        ocmd->header.header.status = -EIO;  // device doesn't exist
+        luxSendDependency(ocmd);
+        return;
+    }
+
+    LXFSDirectoryEntry entry;
+    if(!lxfsFind(&entry, mp, ocmd->path)) {
+        ocmd->header.header.status = -ENOENT;   // file doesn't exist
+        luxSendDependency(ocmd);
+        return;
+    }
+
+    // ensure this is a directory
+    if(((entry.flags >> LXFS_DIR_TYPE_SHIFT) & LXFS_DIR_TYPE_MASK) != LXFS_DIR_TYPE_DIR) {
+        ocmd->header.header.status = -EISDIR;
+        luxSendDependency(ocmd);
+        return;
+    }
+
+    // and ensure adequate permissions (execute)
+    ocmd->header.header.status = 0;
+    if((ocmd->uid == entry.owner) && !(entry.permissions & LXFS_PERMS_OWNER_X))
+        ocmd->header.header.status = -EPERM;
+    else if((ocmd->gid == entry.group) && !(entry.permissions & LXFS_PERMS_GROUP_X))
+        ocmd->header.header.status = -EPERM;
+    else if(!(entry.permissions & LXFS_PERMS_OTHER_X))
+        ocmd->header.header.status = -EPERM;
+
+    luxSendDependency(ocmd);
+}

fs/lxfs/src/include/lxfs/lxfs.h

@@ -131,3 +131,5 @@ void lxfsOpen(OpenCommand *);
 void lxfsStat(StatCommand *);
 void lxfsRead(RWCommand *);
 void lxfsWrite(RWCommand *);
+void lxfsOpendir(OpendirCommand *);
+void lxfsReaddir(ReaddirCommand *);

fs/lxfs/src/main.c

@@ -55,6 +55,7 @@ int main() {
             case COMMAND_OPEN: lxfsOpen((OpenCommand *) msg); break;
             case COMMAND_READ: lxfsRead((RWCommand *) msg); break;
             case COMMAND_STAT: lxfsStat((StatCommand *) msg); break;
+            case COMMAND_OPENDIR: lxfsOpendir((OpendirCommand *) msg); break;
             default:
                 luxLogf(KPRINT_LEVEL_WARNING, "unimplemented command 0x%04X, dropping message...\n", msg->header.command);
             }