More work towards getting bash to build.

Implemented some syscalls: dup(), dup2(), getdtablesize(). FileHandle is now a retainable, since that's needed for dup()'ed fd's. I didn't really test any of this beyond a basic smoke check.
luteresa · Nov 5, 2018 · 9f2b9c8 · 9f2b9c8
1 parent 82f84ba
commit 9f2b9c8
Show file tree

Hide file tree

Showing 17 changed files with 114 additions and 23 deletions.
diff --git a/Kernel/Process.cpp b/Kernel/Process.cpp
@@ -1158,7 +1158,6 @@ int Process::sys$open(const char* path, int options)
  if (!m_file_descriptors[fd])
  break;
  }
- handle->setFD(fd);
  m_file_descriptors[fd] = move(handle);
  return fd;
 }
@@ -1435,3 +1434,35 @@ int Process::sys$tcsetpgrp(int fd, pid_t pgid)
  tty.set_pgid(pgid);
  return 0;
 }
+
+int Process::sys$getdtablesize()
+{
+ return m_max_open_file_descriptors;
+}
+
+int Process::sys$dup(int old_fd)
+{
+ auto* handle = fileHandleIfExists(old_fd);
+ if (!handle)
+ return -EBADF;
+ if (number_of_open_file_descriptors() == m_max_open_file_descriptors)
+ return -EMFILE;
+ int new_fd = 0;
+ for (; new_fd < m_max_open_file_descriptors; ++new_fd) {
+ if (!m_file_descriptors[new_fd])
+ break;
+ }
+ m_file_descriptors[new_fd] = handle;
+ return new_fd;
+}
+
+int Process::sys$dup2(int old_fd, int new_fd)
+{
+ auto* handle = fileHandleIfExists(old_fd);
+ if (!handle)
+ return -EBADF;
+ if (number_of_open_file_descriptors() == m_max_open_file_descriptors)
+ return -EMFILE;
+ m_file_descriptors[new_fd] = handle;
+ return new_fd;
+}
diff --git a/Kernel/Process.h b/Kernel/Process.h
@@ -126,6 +126,9 @@ class Process : public InlineLinkedListNode<Process> {
  int sys$execve(const char* filename, const char** argv, const char** envp);
  Unix::sighandler_t sys$signal(int signum, Unix::sighandler_t);
  int sys$isatty(int fd);
+ int sys$getdtablesize();
+ int sys$dup(int oldfd);
+ int sys$dup2(int oldfd, int newfd);
 
  static void initialize();
 
@@ -193,7 +196,7 @@ class Process : public InlineLinkedListNode<Process> {
  State m_state { Invalid };
  DWORD m_wakeupTime { 0 };
  TSS32 m_tss;
- Vector<OwnPtr<FileHandle>> m_file_descriptors;
+ Vector<RetainPtr<FileHandle>> m_file_descriptors;
  RingLevel m_ring { Ring0 };
  int m_error { 0 };
  void* m_kernelStack { nullptr };

diff --git a/Kernel/Syscall.cpp b/Kernel/Syscall.cpp
@@ -140,6 +140,12 @@ static DWORD handle(RegisterDump& regs, DWORD function, DWORD arg1, DWORD arg2,
  return (dword)current->sys$signal((int)arg1, (Unix::sighandler_t)arg2);
  case Syscall::PosixIsatty:
  return current->sys$isatty((int)arg1);
+ case Syscall::Getdtablesize:
+ return current->sys$getdtablesize();
+ case Syscall::Dup:
+ return current->sys$dup((int)arg1);
+ case Syscall::Dup2:
+ return current->sys$dup2((int)arg1, (int)arg2);
  default:
  kprintf("<%u> int0x80: Unknown function %x requested {%x, %x, %x}\n", current->pid(), function, arg1, arg2, arg3);
  break;

diff --git a/Kernel/Syscall.h b/Kernel/Syscall.h
@@ -53,6 +53,9 @@ enum Function {
  PosixGetegid = 0x2021,
  PosixSignal = 0x2022,
  PosixIsatty = 0x2023,
+ Getdtablesize = 0x2024,
+ Dup = 0x2025,
+ Dup2 = 0x2026,
 };
 
 void initialize();

diff --git a/LibC/dirent.cpp b/LibC/dirent.cpp
@@ -3,6 +3,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <errno.h>
 #include <Kernel/Syscall.h>
 
 extern "C" {
@@ -20,6 +21,16 @@ DIR* opendir(const char* name)
  return dirp;
 }
 
+int closedir(DIR* dirp)
+{
+ if (!dirp || dirp->fd == -1)
+ return -EBADF;
+ int rc = close(dirp->fd);
+ if (rc == 0)
+ dirp->fd = -1;
+ return rc;
+}
+
 struct sys_dirent {
  ino_t ino;
  byte file_type;

diff --git a/LibC/dirent.h b/LibC/dirent.h
@@ -23,7 +23,8 @@ struct __DIR {
 typedef struct __DIR DIR;
 
 DIR* opendir(const char* name);
-struct dirent* readdir(DIR* dirp);
+int closedir(DIR*);
+struct dirent* readdir(DIR*);
 
 __END_DECLS
 
diff --git a/LibC/stdio.cpp b/LibC/stdio.cpp
@@ -193,6 +193,17 @@ FILE* fopen(const char* pathname, const char* mode)
  return fp;
 }
 
+FILE* fdopen(int fd, const char* mode)
+{
+ assert(!strcmp(mode, "r") || !strcmp(mode, "rb"));
+ if (fd < 0)
+ return nullptr;
+ auto* fp = (FILE*)malloc(sizeof(FILE));
+ fp->fd = fd;
+ fp->eof = false;
+ return fp;
+}
+
 int fclose(FILE* stream)
 {
  int rc = close(stream->fd);

diff --git a/LibC/stdio.h b/LibC/stdio.h
@@ -29,6 +29,7 @@ int fileno(FILE*);
 int fgetc(FILE*);
 int getc(FILE*);
 int getchar();
+FILE* fdopen(int fd, const char* mode);
 FILE* fopen(const char* pathname, const char* mode);
 int fclose(FILE*);
 void rewind(FILE*);

diff --git a/LibC/sys/resource.h b/LibC/sys/resource.h
diff --git a/LibC/unistd.cpp b/LibC/unistd.cpp
@@ -190,5 +190,22 @@ int isatty(int fd)
  __RETURN_WITH_ERRNO(rc, 1, 0);
 }
 
+int getdtablesize()
+{
+ int rc = Syscall::invoke(Syscall::Getdtablesize);
+ __RETURN_WITH_ERRNO(rc, 1, 0);
+}
+
+int dup(int old_fd)
+{
+ int rc = Syscall::invoke(Syscall::Dup, (dword)old_fd);
+ __RETURN_WITH_ERRNO(rc, rc, -1);
 }
 
+int dup2(int old_fd, int new_fd)
+{
+ int rc = Syscall::invoke(Syscall::Dup2, (dword)old_fd, (dword)new_fd);
+ __RETURN_WITH_ERRNO(rc, rc, -1);
+}
+
+}
diff --git a/LibC/unistd.h b/LibC/unistd.h
@@ -39,6 +39,9 @@ int ttyname_r(int fd, char* buffer, size_t);
 off_t lseek(int fd, off_t, int whence);
 int link(const char* oldpath, const char* newpath);
 int unlink(const char* pathname);
+int getdtablesize();
+int dup(int old_fd);
+int dup2(int old_fd, int new_fd);
 
 #define WEXITSTATUS(status) (((status) & 0xff00) >> 8)
 #define WTERMSIG(status) ((status) & 0x7f)

diff --git a/VirtualFileSystem/CharacterDevice.cpp b/VirtualFileSystem/CharacterDevice.cpp
@@ -4,7 +4,7 @@ CharacterDevice::~CharacterDevice()
 {
 }
 
-OwnPtr<FileHandle> CharacterDevice::open(int options)
+RetainPtr<FileHandle> CharacterDevice::open(int options)
 {
  return VirtualFileSystem::the().open(*this, options);
 }
diff --git a/VirtualFileSystem/CharacterDevice.h b/VirtualFileSystem/CharacterDevice.h
@@ -8,7 +8,7 @@ class CharacterDevice {
 public:
  virtual ~CharacterDevice();
 
- virtual OwnPtr<FileHandle> open(int options);
+ RetainPtr<FileHandle> open(int options);
 
  virtual bool hasDataAvailableForRead() const = 0;
 

diff --git a/VirtualFileSystem/FileHandle.cpp b/VirtualFileSystem/FileHandle.cpp
@@ -6,6 +6,11 @@
 #include "TTY.h"
 #include <AK/BufferStream.h>
 
+RetainPtr<FileHandle> FileHandle::create(RetainPtr<VirtualFileSystem::Node>&& vnode)
+{
+ return adopt(*new FileHandle(move(vnode)));
+}
+
 FileHandle::FileHandle(RetainPtr<VirtualFileSystem::Node>&& vnode)
  : m_vnode(move(vnode))
 {
@@ -15,9 +20,9 @@ FileHandle::~FileHandle()
 {
 }
 
-OwnPtr<FileHandle> FileHandle::clone()
+RetainPtr<FileHandle> FileHandle::clone()
 {
- auto handle = make<FileHandle>(m_vnode.copyRef());
+ auto handle = FileHandle::create(m_vnode.copyRef());
  if (!handle)
  return nullptr;
  handle->m_currentOffset = m_currentOffset;

diff --git a/VirtualFileSystem/FileHandle.h b/VirtualFileSystem/FileHandle.h
@@ -3,15 +3,16 @@
 #include "VirtualFileSystem.h"
 #include "InodeMetadata.h"
 #include <AK/ByteBuffer.h>
+#include <AK/Retainable.h>
 
 class TTY;
 
-class FileHandle {
+class FileHandle : public Retainable<FileHandle> {
 public:
- explicit FileHandle(RetainPtr<VirtualFileSystem::Node>&&);
+ static RetainPtr<FileHandle> create(RetainPtr<VirtualFileSystem::Node>&&);
  ~FileHandle();
 
- OwnPtr<FileHandle> clone();
+ RetainPtr<FileHandle> clone();
 
  int close();
 
@@ -39,9 +40,6 @@ class FileHandle {
  VirtualFileSystem::Node* vnode() { return m_vnode.ptr(); }
 
 #ifdef SERENITY
- int fd() const { return m_fd; }
- void setFD(int fd) { m_fd = fd; }
-
  bool isBlocking() const { return m_isBlocking; }
  void setBlocking(bool b) { m_isBlocking = b; }
 #endif
@@ -50,6 +48,7 @@ class FileHandle {
 
 private:
  friend class VirtualFileSystem;
+ explicit FileHandle(RetainPtr<VirtualFileSystem::Node>&&);
 
  RetainPtr<VirtualFileSystem::Node> m_vnode;
 

diff --git a/VirtualFileSystem/VirtualFileSystem.cpp b/VirtualFileSystem/VirtualFileSystem.cpp
@@ -398,34 +398,34 @@ bool VirtualFileSystem::touch(const String& path)
  return inode.fileSystem()->setModificationTime(inode, ktime(nullptr));
 }
 
-OwnPtr<FileHandle> VirtualFileSystem::open(CharacterDevice& device, int options)
+RetainPtr<FileHandle> VirtualFileSystem::open(CharacterDevice& device, int options)
 {
  auto vnode = getOrCreateNode(device);
  if (!vnode)
  return nullptr;
- return make<FileHandle>(move(vnode));
+ return FileHandle::create(move(vnode));
 }
 
-OwnPtr<FileHandle> VirtualFileSystem::open(const String& path, int& error, int options, InodeIdentifier base)
+RetainPtr<FileHandle> VirtualFileSystem::open(const String& path, int& error, int options, InodeIdentifier base)
 {
  auto inode = resolvePath(path, error, base, options);
  if (!inode.isValid())
  return nullptr;
  auto vnode = getOrCreateNode(inode);
  if (!vnode)
  return nullptr;
- return make<FileHandle>(move(vnode));
+ return FileHandle::create(move(vnode));
 }
 
-OwnPtr<FileHandle> VirtualFileSystem::create(const String& path, InodeIdentifier base)
+RetainPtr<FileHandle> VirtualFileSystem::create(const String& path, InodeIdentifier base)
 {
  // FIXME: Do the real thing, not just this fake thing!
  (void) path;
  m_rootNode->fileSystem()->createInode(m_rootNode->fileSystem()->rootInode(), "empty", 0100644, 0);
  return nullptr;
 }
 
-OwnPtr<FileHandle> VirtualFileSystem::mkdir(const String& path, InodeIdentifier base)
+RetainPtr<FileHandle> VirtualFileSystem::mkdir(const String& path, InodeIdentifier base)
 {
  // FIXME: Do the real thing, not just this fake thing!
  (void) path;

diff --git a/VirtualFileSystem/VirtualFileSystem.h b/VirtualFileSystem/VirtualFileSystem.h
@@ -93,10 +93,10 @@ class VirtualFileSystem {
  bool mountRoot(RetainPtr<FileSystem>&&);
  bool mount(RetainPtr<FileSystem>&&, const String& path);
 
- OwnPtr<FileHandle> open(CharacterDevice&, int options);
- OwnPtr<FileHandle> open(const String& path, int& error, int options = 0, InodeIdentifier base = InodeIdentifier());
- OwnPtr<FileHandle> create(const String& path, InodeIdentifier base = InodeIdentifier());
- OwnPtr<FileHandle> mkdir(const String& path, InodeIdentifier base = InodeIdentifier());
+ RetainPtr<FileHandle> open(CharacterDevice&, int options);
+ RetainPtr<FileHandle> open(const String& path, int& error, int options = 0, InodeIdentifier base = InodeIdentifier());
+ RetainPtr<FileHandle> create(const String& path, InodeIdentifier base = InodeIdentifier());
+ RetainPtr<FileHandle> mkdir(const String& path, InodeIdentifier base = InodeIdentifier());
 
  bool isRoot(InodeIdentifier) const;