From 6778abb99950efaea21bdd220a18129f575598c3 Mon Sep 17 00:00:00 2001
From: Sergey Bugaev <bugaevc@gmail.com>
Date: Sat, 17 Aug 2019 12:33:39 +0300
Subject: [PATCH] Kernel+SystemServer: Mount filesystems and start TTYServer in
 userspace

---
 Base/etc/fstab                |  4 ++++
 Kernel/init.cpp               | 37 +--------------------------------
 Servers/SystemServer/main.cpp | 39 ++++++++++++++++++++++++++++-------
 3 files changed, 36 insertions(+), 44 deletions(-)
 create mode 100644 Base/etc/fstab

diff --git a/Base/etc/fstab b/Base/etc/fstab
new file mode 100644
index 0000000000..cd18feb762
--- /dev/null
+++ b/Base/etc/fstab
@@ -0,0 +1,4 @@
+/dev/hda	/	ext2
+proc	/proc	proc
+devpts	/dev/pts	devpts
+tmp	/tmp	tmp
diff --git a/Kernel/init.cpp b/Kernel/init.cpp
index 650cbb8992..1cfa0157fd 100644
--- a/Kernel/init.cpp
+++ b/Kernel/init.cpp
@@ -118,20 +118,6 @@ VFS* vfs;
     load_ksyms();
     dbgprintf("Loaded ksyms\n");
 
-    // TODO: we should mount these from SystemServer
-    auto procfs = ProcFS::create();
-    procfs->initialize();
-    vfs->mount(procfs, "/proc");
-
-    auto devptsfs = DevPtsFS::create();
-    devptsfs->initialize();
-    vfs->mount(devptsfs, "/dev/pts");
-
-    auto tmpfs = TmpFS::create();
-    if (!tmpfs->initialize())
-        ASSERT_NOT_REACHED();
-    vfs->mount(move(tmpfs), "/tmp");
-
     // Now, detect whether or not there are actually any floppy disks attached to the system
     u8 detect = CMOS::read(0x10);
     RefPtr<FloppyDiskDevice> fd0;
@@ -152,34 +138,13 @@ VFS* vfs;
 
     int error;
 
-    auto* system_server_process = Process::create_user_process("/bin/SystemServer", (uid_t)100, (gid_t)100, (pid_t)0, error, {}, {}, tty0);
+    auto* system_server_process = Process::create_user_process("/bin/SystemServer", (uid_t)0, (gid_t)0, (pid_t)0, error, {}, {}, tty0);
     if (error != 0) {
         kprintf("init_stage2: error spawning SystemServer: %d\n", error);
         hang();
     }
     system_server_process->set_priority(Process::HighPriority);
 
-    auto* tty1_process = Process::create_user_process("/bin/TTYServer", (uid_t)0, (gid_t)0, (pid_t)0, error, { "/bin/TTYServer", "tty1" }, {}, tty1);
-    if (error != 0) {
-        kprintf("init_stage2: error spawning TTYServer for tty1: %d\n", error);
-        hang();
-    }
-    tty1_process->set_priority(Process::HighPriority);
-
-    auto* tty2_process = Process::create_user_process("/bin/TTYServer", (uid_t)0, (gid_t)0, (pid_t)0, error, { "/bin/TTYServer", "tty2" }, {}, tty2);
-    if (error != 0) {
-        kprintf("init_stage2: error spawning TTYServer for tty2: %d\n", error);
-        hang();
-    }
-    tty2_process->set_priority(Process::HighPriority);
-
-    auto* tty3_process = Process::create_user_process("/bin/TTYServer", (uid_t)0, (gid_t)0, (pid_t)0, error, { "/bin/TTYServer", "tty3" }, {}, tty3);
-    if (error != 0) {
-        kprintf("init_stage2: error spawning TTYServer for tty3: %d\n", error);
-        hang();
-    }
-    tty3_process->set_priority(Process::HighPriority);
-
     current->process().sys$exit(0);
     ASSERT_NOT_REACHED();
 }
diff --git a/Servers/SystemServer/main.cpp b/Servers/SystemServer/main.cpp
index 57cda02920..43a688e392 100644
--- a/Servers/SystemServer/main.cpp
+++ b/Servers/SystemServer/main.cpp
@@ -1,13 +1,14 @@
 #include <AK/Assertions.h>
 #include <LibCore/CFile.h>
 #include <errno.h>
+#include <fcntl.h>
 #include <sched.h>
 #include <stdio.h>
 #include <string.h>
 #include <sys/types.h>
 #include <unistd.h>
 
-void start_process(const char* prog, int prio)
+void start_process(const char* prog, const char* arg, int prio, const char* tty = nullptr)
 {
     pid_t pid = 0;
 
@@ -32,9 +33,17 @@ void start_process(const char* prog, int prio)
         int ret = sched_setparam(pid, &p);
         ASSERT(ret == 0);
 
+        if (tty != nullptr) {
+            close(0);
+            ASSERT(open(tty, O_RDWR) == 0);
+            dup2(0, 1);
+            dup2(0, 2);
+        }
+
         char* progv[256];
         progv[0] = const_cast<char*>(prog);
-        progv[1] = nullptr;
+        progv[1] = const_cast<char*>(arg);
+        progv[2] = nullptr;
         ret = execv(prog, progv);
         if (ret < 0) {
             dbgprintf("Exec %s failed! %s", prog, strerror(errno));
@@ -72,12 +81,26 @@ int main(int, char**)
 {
     int lowest_prio = sched_get_priority_min(SCHED_OTHER);
     int highest_prio = sched_get_priority_max(SCHED_OTHER);
-    start_process("/bin/LookupServer", lowest_prio);
-    start_process("/bin/WindowServer", highest_prio);
-    start_process("/bin/AudioServer", highest_prio);
-    start_process("/bin/Taskbar", highest_prio);
-    start_process("/bin/Terminal", highest_prio - 1);
-    start_process("/bin/Launcher", highest_prio);
+
+    // Mount the filesystems.
+    start_process("/bin/mount", "-a", highest_prio);
+    wait(nullptr);
+
+    start_process("/bin/TTYServer", "tty0", highest_prio, "/dev/tty0");
+    start_process("/bin/TTYServer", "tty1", highest_prio, "/dev/tty1");
+    start_process("/bin/TTYServer", "tty2", highest_prio, "/dev/tty2");
+    start_process("/bin/TTYServer", "tty3", highest_prio, "/dev/tty3");
+
+    // Drop privileges.
+    setuid(100);
+    setgid(100);
+
+    start_process("/bin/LookupServer", nullptr, lowest_prio);
+    start_process("/bin/WindowServer", nullptr, highest_prio);
+    start_process("/bin/AudioServer", nullptr, highest_prio);
+    start_process("/bin/Taskbar", nullptr, highest_prio);
+    start_process("/bin/Terminal", nullptr, highest_prio - 1);
+    start_process("/bin/Launcher", nullptr, highest_prio);
 
     // This won't return if we're in test mode.
     check_for_test_mode();