procfs: refactored and implemented open()

fs/procfs/src/include/procfs/procfs.h

@@ -32,10 +32,12 @@
 #define RESOLVE_PID_CHILDREN        (9 | RESOLVE_PID)   /* /proc/pid/children */
 #define RESOLVE_PID_STAT            (10 | RESOLVE_PID)  /* /proc/pid/stat */
 
-void procfsMount(MountCommand *, MountCommand *);
-void procfsStat(StatCommand *, StatCommand *);
-void procfsOpen(OpenCommand *, OpenCommand *);
-void procfsRead(RWCommand *, RWCommand *);
-void procfsWrite(RWCommand *, RWCommand *);
+#define RESOLVE_DIRECTORY           0x10000
 
-int procfsResolve(const char *, pid_t *);
+void procfsMount(MountCommand *);
+void procfsStat(StatCommand *);
+void procfsOpen(OpenCommand *);
+void procfsRead(RWCommand *);
+void procfsWrite(RWCommand *);
+
+int resolve(const char *, pid_t *);

fs/procfs/src/io.c

@@ -0,0 +1,40 @@
+/*
+ * luxOS - a unix-like operating system
+ * Omar Elghoul, 2024
+ * 
+ * procfs: Microkernel server implementing the /proc file system
+ */
+
+#include <procfs/procfs.h>
+#include <liblux/liblux.h>
+#include <string.h>
+#include <stdlib.h>
+#include <fnctl.h>
+#include <errno.h>
+
+void procfsOpen(OpenCommand *ocmd) {
+    pid_t pid;
+
+    ocmd->header.header.response = 1;
+    ocmd->header.header.length = sizeof(OpenCommand);
+
+    int res = resolve(ocmd->path, &pid);
+    if(res < 0) {
+        ocmd->header.header.status = -ENOENT;
+        luxSendDependency(ocmd);
+        return;
+    }
+
+    if(res & RESOLVE_DIRECTORY) {
+        ocmd->header.header.status = -EISDIR;
+        luxSendDependency(ocmd);
+        return;
+    }
+
+    if(ocmd->flags & O_WRONLY)
+        ocmd->header.header.status = -EPERM;
+    else
+        ocmd->header.header.status = 0;
+
+    luxSendDependency(ocmd);
+}

fs/procfs/src/main.c

@@ -52,7 +52,8 @@ int main() {
             luxRecvDependency(req, req->header.length, false, false);
 
             switch(req->header.command) {
-            case COMMAND_MOUNT: procfsMount((MountCommand *) req, (MountCommand *) res); break;
+            case COMMAND_MOUNT: procfsMount((MountCommand *) req); break;
+            case COMMAND_OPEN: procfsOpen((OpenCommand *) req); break;
             default:
                 luxLogf(KPRINT_LEVEL_WARNING, "unimplemented command 0x%X, dropping message...\n", req->header.command);
             }

fs/procfs/src/mount.c

@@ -10,15 +10,13 @@
 
 /* procfsMount(): mounts the /proc file system
  * params: req - request buffer
- * params: res - response buffer
  * returns: nothing
  */
 
-void procfsMount(MountCommand *req, MountCommand *res) {
-    memcpy(res, req, sizeof(MountCommand));
-    res->header.header.response = 1;
-    res->header.header.length = sizeof(MountCommand);
-    res->header.header.status = 0;      // success
+void procfsMount(MountCommand *req) {
+    req->header.header.response = 1;
+    req->header.header.length = sizeof(MountCommand);
+    req->header.header.status = 0;      // success
 
-    luxSendDependency(res);
+    luxSendDependency(req);
 }