Changeset 4ec6820 in mainline for uspace/lib/posix/fcntl.c

Timestamp:

2011-06-29T23:16:31Z (14 years ago)

Author:

Petr Koupy <petr.koupy@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

87ba48cb

Parents:

8b5fb5e

Message:

Implemented fcntl.

File:

• uspace/lib/posix/fcntl.c (modified) (1 diff)

uspace/lib/posix/fcntl.c

@@ -37 +37 @@
 #include "internal/common.h"
 #include "fcntl.h"
+#include "libc/unistd.h"
+#include "libc/vfs/vfs.h"
+#include <errno.h>
 
 /**
- * 
- * @param fd
- * @param cmd
- * @param ...
- * @return
+ * Performs set of operations on the opened files.
+ *
+ * @param fd File descriptor of the opened file.
+ * @param cmd Operation to carry out.
+ * @return Non-negative on success. Might have special meaning corresponding
+ *     to the requested operation.
  */
 int posix_fcntl(int fd, int cmd, ...)
 {
-        // TODO
-        not_implemented();
+        int rc;
+        int flags;
+
+        switch (cmd) {
+        case F_DUPFD:
+        case F_DUPFD_CLOEXEC: /* FD_CLOEXEC is not supported. */
+                /* VFS does not provide means to express constraints on the new
+                 * file descriptor so the third argument is ignored. */
+
+                /* Retrieve node triplet corresponding to the file descriptor. */
+                /* Empty statement after label. */;
+                fdi_node_t node;
+                rc = fd_node(fd, &node);
+                if (rc != EOK) {
+                        // TODO: propagate a POSIX compatible errno
+                        return -1;
+                }
+
+                /* Reopen the node so the fresh file descriptor is generated. */
+                int newfd = open_node(&node, 0);
+                if (newfd < 0) {
+                        // TODO: propagate a POSIX compatible errno
+                        return -1;
+                }
+
+                /* Associate the newly generated descriptor to the file description
+                 * of the old file descriptor. Just reopened node will be automatically
+                 * closed. */
+                rc = dup2(fd, newfd);
+                if (rc != EOK) {
+                        // TODO: propagate a POSIX compatible errno
+                        return -1;
+                }
+
+                return newfd;
+        case F_GETFD:
+                /* FD_CLOEXEC is not supported. There are no other flags. */
+                return 0;
+        case F_SETFD:
+                /* FD_CLOEXEC is not supported. Ignore arguments and report success. */
+                return 0;
+        case F_GETFL:
+                /* File status flags (i.e. O_APPEND) are currently private to the
+                 * VFS server so it cannot be easily retrieved. */
+                flags = 0;
+                /* File access flags are currently not supported for file descriptors.
+                 * Provide full access. */
+                flags |= O_RDWR;
+                return flags;
+        case F_SETFL:
+                /* File access flags are currently not supported for file descriptors.
+                 * Ignore arguments and report success. */
+                return 0;
+        case F_GETOWN:
+        case F_SETOWN:
+        case F_GETLK:
+        case F_SETLK:
+        case F_SETLKW:
+                /* Signals (SIGURG) and file locks are not supported. */
+                errno = ENOTSUP;
+                return -1;
+        default:
+                /* Unknown command */
+                errno = EINVAL;
+                return -1;
+        }
 }