1 files changed, 421 insertions, 0 deletions
diff --git a/src/vfs/sftpfs/file.c b/src/vfs/sftpfs/file.c
new file mode 100644
index 0000000..f124d17
--- /dev/null
+++ b/src/vfs/sftpfs/file.c
@@ -0,0 +1,421 @@
+/* Virtual File System: SFTP file system.
+   The internal functions: files
+
+   Copyright (C) 2011-2022
+   Free Software Foundation, Inc.
+
+   Written by:
+   Ilia Maslakov <il.smind@gmail.com>, 2011
+   Slava Zanko <slavazanko@gmail.com>, 2011, 2012
+
+   This file is part of the Midnight Commander.
+
+   The Midnight Commander is free software: you can redistribute it
+   and/or modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation, either version 3 of the License,
+   or (at your option) any later version.
+
+   The Midnight Commander is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+
+#include <errno.h>
+#include <libssh2.h>
+#include <libssh2_sftp.h>
+
+#include "lib/global.h"
+#include "lib/util.h"
+
+#include "internal.h"
+
+/*** global variables ****************************************************************************/
+
+/*** file scope macro definitions ****************************************************************/
+
+#define SFTP_FILE_HANDLER(a) ((sftpfs_file_handler_t *) a)
+
+/*** file scope type declarations ****************************************************************/
+
+typedef struct
+{
+    vfs_file_handler_t base;    /* base class */
+
+    LIBSSH2_SFTP_HANDLE *handle;
+    int flags;
+    mode_t mode;
+} sftpfs_file_handler_t;
+
+/*** file scope variables ************************************************************************/
+
+/* --------------------------------------------------------------------------------------------- */
+/*** file scope functions ************************************************************************/
+/* --------------------------------------------------------------------------------------------- */
+/**
+ * Reopen file by file handle.
+ *
+ * @param fh      the file handler
+ * @param mcerror pointer to the error handler
+ */
+static void
+sftpfs_reopen (vfs_file_handler_t * fh, GError ** mcerror)
+{
+    sftpfs_file_handler_t *file = SFTP_FILE_HANDLER (fh);
+    int flags;
+    mode_t mode;
+
+    g_return_if_fail (mcerror == NULL || *mcerror == NULL);
+
+    flags = file->flags;
+    mode = file->mode;
+
+    sftpfs_close_file (fh, mcerror);
+    sftpfs_open_file (fh, flags, mode, mcerror);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static int
+sftpfs_file__handle_error (sftpfs_super_t * super, int sftp_res, GError ** mcerror)
+{
+    if (sftpfs_is_sftp_error (super->sftp_session, sftp_res, LIBSSH2_FX_PERMISSION_DENIED))
+        return -EACCES;
+
+    if (sftpfs_is_sftp_error (super->sftp_session, sftp_res, LIBSSH2_FX_NO_SUCH_FILE))
+        return -ENOENT;
+
+    if (!sftpfs_waitsocket (super, sftp_res, mcerror))
+        return -1;
+
+    return 0;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/*** public functions ****************************************************************************/
+/* --------------------------------------------------------------------------------------------- */
+
+vfs_file_handler_t *
+sftpfs_fh_new (struct vfs_s_inode * ino, gboolean changed)
+{
+    sftpfs_file_handler_t *fh;
+
+    fh = g_new0 (sftpfs_file_handler_t, 1);
+    vfs_s_init_fh (VFS_FILE_HANDLER (fh), ino, changed);
+
+    return VFS_FILE_HANDLER (fh);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+ * Open new SFTP file.
+ *
+ * @param fh      the file handler
+ * @param flags   flags (see man 2 open)
+ * @param mode    mode (see man 2 open)
+ * @param mcerror pointer to the error handler
+ * @return TRUE if connection was created successfully, FALSE otherwise
+ */
+
+gboolean
+sftpfs_open_file (vfs_file_handler_t * fh, int flags, mode_t mode, GError ** mcerror)
+{
+    unsigned long sftp_open_flags = 0;
+    int sftp_open_mode = 0;
+    gboolean do_append = FALSE;
+    sftpfs_file_handler_t *file = SFTP_FILE_HANDLER (fh);
+    sftpfs_super_t *super = SFTP_SUPER (fh->ino->super);
+    char *name;
+    const GString *fixfname;
+
+    (void) mode;
+    mc_return_val_if_error (mcerror, FALSE);
+
+    name = vfs_s_fullpath (vfs_sftpfs_ops, fh->ino);
+    if (name == NULL)
+        return FALSE;
+
+    if ((flags & O_CREAT) != 0 || (flags & O_WRONLY) != 0)
+    {
+        sftp_open_flags = (flags & O_WRONLY) != 0 ? LIBSSH2_FXF_WRITE : 0;
+        sftp_open_flags |= (flags & O_CREAT) != 0 ? LIBSSH2_FXF_CREAT : 0;
+        if ((flags & O_APPEND) != 0)
+        {
+            sftp_open_flags |= LIBSSH2_FXF_APPEND;
+            do_append = TRUE;
+        }
+        sftp_open_flags |= (flags & O_TRUNC) != 0 ? LIBSSH2_FXF_TRUNC : 0;
+
+        sftp_open_mode = LIBSSH2_SFTP_S_IRUSR |
+            LIBSSH2_SFTP_S_IWUSR | LIBSSH2_SFTP_S_IRGRP | LIBSSH2_SFTP_S_IROTH;
+    }
+    else
+        sftp_open_flags = LIBSSH2_FXF_READ;
+
+    fixfname = sftpfs_fix_filename (name);
+
+    while (TRUE)
+    {
+        int libssh_errno;
+
+        file->handle =
+            libssh2_sftp_open_ex (super->sftp_session, fixfname->str, fixfname->len,
+                                  sftp_open_flags, sftp_open_mode, LIBSSH2_SFTP_OPENFILE);
+        if (file->handle != NULL)
+            break;
+
+        libssh_errno = libssh2_session_last_errno (super->session);
+        if (libssh_errno != LIBSSH2_ERROR_EAGAIN)
+        {
+            sftpfs_ssherror_to_gliberror (super, libssh_errno, mcerror);
+            g_free (name);
+            return FALSE;
+        }
+    }
+
+    g_free (name);
+
+    file->flags = flags;
+    file->mode = mode;
+
+    if (do_append)
+    {
+        struct stat file_info = {
+            .st_dev = 0
+        };
+        /* In case of
+
+           struct stat file_info = { 0 };
+
+           gcc < 4.7 [1] generates the following:
+
+           error: missing initializer [-Werror=missing-field-initializers]
+           error: (near initialization for 'file_info.st_dev') [-Werror=missing-field-initializers]
+
+           [1] http://stackoverflow.com/questions/13373695/how-to-remove-the-warning-in-gcc-4-6-missing-initializer-wmissing-field-initi/27461062#27461062
+         */
+
+        if (sftpfs_fstat (fh, &file_info, mcerror) == 0)
+            libssh2_sftp_seek64 (file->handle, file_info.st_size);
+    }
+    return TRUE;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+ * Stats the file specified by the file descriptor.
+ *
+ * @param data    file handler
+ * @param buf     buffer for store stat-info
+ * @param mcerror pointer to the error handler
+ * @return 0 if success, negative value otherwise
+ */
+
+int
+sftpfs_fstat (void *data, struct stat *buf, GError ** mcerror)
+{
+    int res;
+    LIBSSH2_SFTP_ATTRIBUTES attrs;
+    vfs_file_handler_t *fh = VFS_FILE_HANDLER (data);
+    sftpfs_file_handler_t *sftpfs_fh = (sftpfs_file_handler_t *) data;
+    struct vfs_s_super *super = VFS_FILE_HANDLER_SUPER (fh);
+    sftpfs_super_t *sftpfs_super = SFTP_SUPER (super);
+
+    mc_return_val_if_error (mcerror, -1);
+
+    if (sftpfs_fh->handle == NULL)
+        return -1;
+
+    do
+    {
+        int err;
+
+        res = libssh2_sftp_fstat_ex (sftpfs_fh->handle, &attrs, 0);
+        if (res >= 0)
+            break;
+
+        err = sftpfs_file__handle_error (sftpfs_super, res, mcerror);
+        if (err < 0)
+            return err;
+    }
+    while (res == LIBSSH2_ERROR_EAGAIN);
+
+    sftpfs_attr_to_stat (&attrs, buf);
+
+    return 0;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/**
+ * Read up to 'count' bytes from the file descriptor 'fh' to the buffer starting at 'buffer'.
+ *
+ * @param fh      file handler
+ * @param buffer  buffer for data
+ * @param count   data size
+ * @param mcerror pointer to the error handler
+ *
+ * @return 0 on success, negative value otherwise
+ */
+
+ssize_t
+sftpfs_read_file (vfs_file_handler_t * fh, char *buffer, size_t count, GError ** mcerror)
+{
+    ssize_t rc;
+    sftpfs_file_handler_t *file = SFTP_FILE_HANDLER (fh);
+    sftpfs_super_t *super;
+
+    mc_return_val_if_error (mcerror, -1);
+
+    if (fh == NULL)
+    {
+        mc_propagate_error (mcerror, 0, "%s",
+                            _("sftp: No file handler data present for reading file"));
+        return -1;
+    }
+
+    super = SFTP_SUPER (VFS_FILE_HANDLER_SUPER (fh));
+
+    do
+    {
+        int err;
+
+        rc = libssh2_sftp_read (file->handle, buffer, count);
+        if (rc >= 0)
+            break;
+
+        err = sftpfs_file__handle_error (super, (int) rc, mcerror);
+        if (err < 0)
+            return err;
+    }
+    while (rc == LIBSSH2_ERROR_EAGAIN);
+
+    fh->pos = (off_t) libssh2_sftp_tell64 (file->handle);
+
+    return rc;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+/**
+ * Write up to 'count' bytes from  the buffer starting at 'buffer' to the descriptor 'fh'.
+ *
+ * @param fh      file handler
+ * @param buffer  buffer for data
+ * @param count   data size
+ * @param mcerror pointer to the error handler
+ *
+ * @return 0 on success, negative value otherwise
+ */
+
+ssize_t
+sftpfs_write_file (vfs_file_handler_t * fh, const char *buffer, size_t count, GError ** mcerror)
+{
+    ssize_t rc;
+    sftpfs_file_handler_t *file = SFTP_FILE_HANDLER (fh);
+    sftpfs_super_t *super = SFTP_SUPER (VFS_FILE_HANDLER_SUPER (fh));
+
+    mc_return_val_if_error (mcerror, -1);
+
+    fh->pos = (off_t) libssh2_sftp_tell64 (file->handle);
+
+    do
+    {
+        int err;
+
+        rc = libssh2_sftp_write (file->handle, buffer, count);
+        if (rc >= 0)
+            break;
+
+        err = sftpfs_file__handle_error (super, (int) rc, mcerror);
+        if (err < 0)
+            return err;
+    }
+    while (rc == LIBSSH2_ERROR_EAGAIN);
+
+    return rc;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+/**
+ * Close a file descriptor.
+ *
+ * @param fh      file handler
+ * @param mcerror pointer to the error handler
+ *
+ * @return 0 on success, negative value otherwise
+ */
+
+int
+sftpfs_close_file (vfs_file_handler_t * fh, GError ** mcerror)
+{
+    int ret;
+
+    mc_return_val_if_error (mcerror, -1);
+
+    ret = libssh2_sftp_close (SFTP_FILE_HANDLER (fh)->handle);
+
+    return ret == 0 ? 0 : -1;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+/**
+ * Reposition the offset of the open file associated with the file descriptor.
+ *
+ * @param fh      file handler
+ * @param offset  file offset
+ * @param whence  method of seek (at begin, at current, at end)
+ * @param mcerror pointer to the error handler
+ *
+ * @return 0 on success, negative value otherwise
+ */
+
+off_t
+sftpfs_lseek (vfs_file_handler_t * fh, off_t offset, int whence, GError ** mcerror)
+{
+    sftpfs_file_handler_t *file = SFTP_FILE_HANDLER (fh);
+
+    mc_return_val_if_error (mcerror, 0);
+
+    switch (whence)
+    {
+    case SEEK_SET:
+        /* Need reopen file because:
+           "You MUST NOT seek during writing or reading a file with SFTP, as the internals use
+           outstanding packets and changing the "file position" during transit will results in
+           badness." */
+        if (fh->pos > offset || offset == 0)
+        {
+            sftpfs_reopen (fh, mcerror);
+            mc_return_val_if_error (mcerror, 0);
+        }
+        fh->pos = offset;
+        break;
+    case SEEK_CUR:
+        fh->pos += offset;
+        break;
+    case SEEK_END:
+        if (fh->pos > fh->ino->st.st_size - offset)
+        {
+            sftpfs_reopen (fh, mcerror);
+            mc_return_val_if_error (mcerror, 0);
+        }
+        fh->pos = fh->ino->st.st_size - offset;
+        break;
+    default:
+        break;
+    }
+
+    libssh2_sftp_seek64 (file->handle, fh->pos);
+    fh->pos = (off_t) libssh2_sftp_tell64 (file->handle);
+
+    return fh->pos;
+}
+
+/* --------------------------------------------------------------------------------------------- */