Kernel+LibC: Tidy up sys$ttyname() and sys$ptsname()

- Remove goofy _r suffix from syscall names.
- Don't take a signed buffer size.
- Use Userspace<T>.
- Make TTY::tty_name() return a String instead of a StringView.

Kernel/API/Syscall.h

@@ -76,7 +76,7 @@ namespace Kernel {
     S(set_mmap_name)          \
     S(readlink)               \
     S(write)                  \
-    S(ttyname_r)              \
+    S(ttyname)                \
     S(stat)                   \
     S(getsid)                 \
     S(setsid)                 \
@@ -111,7 +111,7 @@ namespace Kernel {
     S(times)                  \
     S(utime)                  \
     S(sync)                   \
-    S(ptsname_r)              \
+    S(ptsname)                \
     S(select)                 \
     S(unlink)                 \
     S(poll)                   \

Kernel/Process.h

@@ -246,8 +246,8 @@ public:
     int sys$sethostname(const char*, ssize_t);
     int sys$uname(utsname*);
     int sys$readlink(const Syscall::SC_readlink_params*);
-    int sys$ttyname_r(int fd, char*, ssize_t);
-    int sys$ptsname_r(int fd, char*, ssize_t);
+    int sys$ttyname(int fd, Userspace<char*>, size_t);
+    int sys$ptsname(int fd, Userspace<char*>, size_t);
     pid_t sys$fork(RegisterState&);
     int sys$execve(const Syscall::SC_execve_params*);
     int sys$dup(int oldfd);

Kernel/Syscalls/ttyname.cpp

@@ -31,11 +31,9 @@
 
 namespace Kernel {
 
-int Process::sys$ttyname_r(int fd, char* buffer, ssize_t size)
+int Process::sys$ttyname(int fd, Userspace<char*> buffer, size_t size)
 {
     REQUIRE_PROMISE(tty);
-    if (size < 0)
-        return -EINVAL;
     if (!validate_write(buffer, size))
         return -EFAULT;
     auto description = file_description(fd);
@@ -43,18 +41,16 @@ int Process::sys$ttyname_r(int fd, char* buffer, ssize_t size)
         return -EBADF;
     if (!description->is_tty())
         return -ENOTTY;
-    String tty_name = description->tty()->tty_name();
-    if ((size_t)size < tty_name.length() + 1)
+    auto tty_name = description->tty()->tty_name();
+    if (size < tty_name.length() + 1)
         return -ERANGE;
     copy_to_user(buffer, tty_name.characters(), tty_name.length() + 1);
     return 0;
 }
 
-int Process::sys$ptsname_r(int fd, char* buffer, ssize_t size)
+int Process::sys$ptsname(int fd, Userspace<char*> buffer, size_t size)
 {
     REQUIRE_PROMISE(tty);
-    if (size < 0)
-        return -EINVAL;
     if (!validate_write(buffer, size))
         return -EFAULT;
     auto description = file_description(fd);
@@ -64,7 +60,7 @@ int Process::sys$ptsname_r(int fd, char* buffer, ssize_t size)
     if (!master_pty)
         return -ENOTTY;
     auto pts_name = master_pty->pts_name();
-    if ((size_t)size < pts_name.length() + 1)
+    if (size < pts_name.length() + 1)
         return -ERANGE;
     copy_to_user(buffer, pts_name.characters(), pts_name.length() + 1);
     return 0;

Kernel/TTY/SlavePTY.cpp

@@ -54,7 +54,7 @@ SlavePTY::~SlavePTY()
     DevPtsFS::unregister_slave_pty(*this);
 }
 
-StringView SlavePTY::tty_name() const
+String SlavePTY::tty_name() const
 {
     return m_tty_name;
 }

Kernel/TTY/SlavePTY.h

@@ -42,7 +42,7 @@ public:
 
 private:
     // ^TTY
-    virtual StringView tty_name() const override;
+    virtual String tty_name() const override;
     virtual ssize_t on_tty_write(const u8*, ssize_t) override;
     virtual void echo(u8) override;
 

Kernel/TTY/TTY.h

@@ -46,7 +46,7 @@ public:
     virtual int ioctl(FileDescription&, unsigned request, FlatPtr arg) override final;
     virtual String absolute_path(const FileDescription&) const override { return tty_name(); }
 
-    virtual StringView tty_name() const = 0;
+    virtual String tty_name() const = 0;
 
     unsigned short rows() const { return m_rows; }
     unsigned short columns() const { return m_columns; }

Kernel/TTY/VirtualConsole.h

@@ -55,7 +55,7 @@ private:
 
     // ^TTY
     virtual ssize_t on_tty_write(const u8*, ssize_t) override;
-    virtual StringView tty_name() const override { return m_tty_name; }
+    virtual String tty_name() const override { return m_tty_name; }
     virtual void echo(u8) override;
 
     // ^TerminalClient

Libraries/LibC/stdlib.cpp

@@ -670,7 +670,7 @@ char* ptsname(int fd)
 
 int ptsname_r(int fd, char* buffer, size_t size)
 {
-    int rc = syscall(SC_ptsname_r, fd, buffer, size);
+    int rc = syscall(SC_ptsname, fd, buffer, size);
     __RETURN_WITH_ERRNO(rc, rc, -1);
 }
 

Libraries/LibC/unistd.cpp

@@ -279,7 +279,7 @@ ssize_t write(int fd, const void* buf, size_t count)
 
 int ttyname_r(int fd, char* buffer, size_t size)
 {
-    int rc = syscall(SC_ttyname_r, fd, buffer, size);
+    int rc = syscall(SC_ttyname, fd, buffer, size);
     __RETURN_WITH_ERRNO(rc, rc, -1);
 }