Add libssh2_sftp_statvfs() and libssh2_sftp_fstatvfs()

These can be used to get file system statistics from servers that
support the statvfs@openssh.com and fstatvfs@openssh.com extensions.

docs/Makefile.am

@@ -113,6 +113,7 @@ dist_man_MANS = \
 	libssh2_sftp_fsetstat.3 \
 	libssh2_sftp_fstat.3 \
 	libssh2_sftp_fstat_ex.3 \
+	libssh2_sftp_fstatvfs.3 \
 	libssh2_sftp_init.3 \
 	libssh2_sftp_last_error.3 \
 	libssh2_sftp_lstat.3 \
@@ -136,6 +137,8 @@ dist_man_MANS = \
 	libssh2_sftp_shutdown.3 \
 	libssh2_sftp_stat.3 \
 	libssh2_sftp_stat_ex.3 \
+	libssh2_sftp_statvfs.3 \
+	libssh2_sftp_statvfs_ex.3 \
 	libssh2_sftp_symlink.3 \
 	libssh2_sftp_symlink_ex.3 \
 	libssh2_sftp_tell.3 \

docs/libssh2_sftp_fstatvfs.3

@@ -0,0 +1 @@
+.so man3/libssh2_sftp_statvfs.3

docs/libssh2_sftp_statvfs.3

@@ -0,0 +1,81 @@
+.TH libssh2_sftp_statvfs 3 "22 May 2010" "libssh2 1.2.6" "libssh2 manual"
+.SH NAME
+libssh2_sftp_statvfs, libssh2_sftp_fstatvfs - get file system statistics
+.SH SYNOPSIS
+.nf
+#include <libssh2.h>
+#include <libssh2_sftp.h>
+
+int
+libssh2_sftp_statvfs_ex(LIBSSH2_SFTP *sftp, const char *path,
+                        unsigned int path_len, LIBSSH2_SFTP_STATVFS *st);
+#define libssh2_sftp_statvfs(sftp, path, st) \\
+    libssh2_sftp_statvfs_ex((sftp), (path), strlen(path), (st))
+
+int
+libssh2_sftp_fstatvfs(LIBSSH2_SFTP_HANDLE *handle,
+                      LIBSSH2_SFTP_STATVFS *st)
+.fi
+.SH DESCRIPTION
+These functions provide statvfs(2)-like operations and require
+statvfs@openssh.com and fstatvfs@openssh.com extension support on the server.
+
+\fIsftp\fP - SFTP instance as returned by
+.BR libssh2_sftp_init(3)
+
+\fIhandle\fP - SFTP File Handle as returned by
+.BR libssh2_sftp_open_ex(3)
+
+\fIpath\fP - full path of any file within the mounted file system.
+
+\fIpath_len\fP - length of the full path.
+
+\fIst\fP - Pointer to a LIBSSH2_SFTP_STATVFS structure to place file system
+statistics into.
+
+.SH DATA TYPES
+LIBSSH2_SFTP_STATVFS is a typedefed struct that is defined as below
+
+.nf
+struct _LIBSSH2_SFTP_STATVFS {
+    libssh2_uint64_t  f_bsize;    /* file system block size */
+    libssh2_uint64_t  f_frsize;   /* fragment size */
+    libssh2_uint64_t  f_blocks;   /* size of fs in f_frsize units */
+    libssh2_uint64_t  f_bfree;    /* # free blocks */
+    libssh2_uint64_t  f_bavail;   /* # free blocks for non-root */
+    libssh2_uint64_t  f_files;    /* # inodes */
+    libssh2_uint64_t  f_ffree;    /* # free inodes */
+    libssh2_uint64_t  f_favail;   /* # free inodes for non-root */
+    libssh2_uint64_t  f_fsid;     /* file system ID */
+    libssh2_uint64_t  f_flag;     /* mount flags */
+    libssh2_uint64_t  f_namemax;  /* maximum filename length */
+};
+.fi
+
+It is unspecified whether all members of the returned struct have meaningful
+values on all file systems.
+
+The field \fIf_flag\fP is a bit mask. Bits are defined as follows:
+.IP LIBSSH2_SFTP_ST_RDONLY
+Read-only file system.
+.IP LIBSSH2_SFTP_ST_NOSUID
+Set-user-ID/set-group-ID bits are ignored by \fBexec\fP(3).
+
+.SH RETURN VALUE
+Returns 0 on success or negative on failure. If used in non-blocking mode, it
+returns LIBSSH2_ERROR_EAGAIN when it would otherwise block. While
+LIBSSH2_ERROR_EAGAIN is a negative number, it isn't really a failure per se.
+.SH ERRORS
+\fILIBSSH2_ERROR_ALLOC\fP -  An internal memory allocation call failed.
+
+\fILIBSSH2_ERROR_SOCKET_SEND\fP - Unable to send data on socket.
+
+\fILIBSSH2_ERROR_SOCKET_TIMEOUT\fP - 
+
+\fILIBSSH2_ERROR_SFTP_PROTOCOL\fP - An invalid SFTP protocol response was
+received on the socket, or an SFTP operation caused an errorcode to be returned
+by the server.
+.SH AVAILABILITY
+Added in libssh2 1.2.6
+.SH SEE ALSO
+.BR libssh2_sftp_open_ex(3)

docs/libssh2_sftp_statvfs_ex.3

@@ -0,0 +1 @@
+.so man3/libssh2_sftp_statvfs.3