Merge pull request #820 from brendanzagaeski/master

[mono.git] / mcs / class / Mono.Posix / Mono.Unix.Native / Syscall.cs

diff --git a/mcs/class/Mono.Posix/Mono.Unix.Native/Syscall.cs b/mcs/class/Mono.Posix/Mono.Unix.Native/Syscall.cs
index 27d241539d5a7e3a35ea4d74436ff211bdfd4afb..7ba53e922bf7d1dd53db2206246a8281c522af7c 100644 (file)
--- a/mcs/class/Mono.Posix/Mono.Unix.Native/Syscall.cs
+++ b/mcs/class/Mono.Posix/Mono.Unix.Native/Syscall.cs
@@ -2305,7 +2305,7 @@ namespace Mono.Unix.Native {
                        // Syscall to getpwnam to retrieve user uid
                        Passwd pw = Syscall.getpwnam (username);
                        if (pw == null)
-                               throw new ArgumentException (string.Format ("User {0} does not exists",username), "username");
+                               throw new ArgumentException (string.Format ("User {0} does not exist", username), "username");
                        return getgrouplist (pw);
                }
 
@@ -3937,17 +3937,51 @@ namespace Mono.Unix.Native {
                                [MarshalAs (UnmanagedType.CustomMarshaler, MarshalTypeRef=typeof(FileNameMarshaler))]
                                string newpath);
 
+               delegate long DoReadlinkFun (byte[] target);
+
+               // Helper function for readlink(string, StringBuilder) and readlinkat (int, string, StringBuilder)
+               static int ReadlinkIntoStringBuilder (DoReadlinkFun doReadlink, [Out] StringBuilder buf, ulong bufsiz)
+               {
+                       // bufsiz > int.MaxValue can't work because StringBuilder can store only int.MaxValue chars
+                       int bufsizInt = checked ((int) bufsiz);
+                       var target = new byte [bufsizInt];
+
+                       var r = doReadlink (target);
+                       if (r < 0)
+                               return checked ((int) r);
+
+                       buf.Length = 0;
+                       var chars = UnixEncoding.Instance.GetChars (target, 0, checked ((int) r));
+                       // Make sure that at more bufsiz chars are written
+                       buf.Append (chars, 0, System.Math.Min (bufsizInt, chars.Length));
+                       if (r == bufsizInt) {
+                               // may not have read full contents; fill 'buf' so that caller can properly check
+                               buf.Append (new string ('\x00', bufsizInt - buf.Length));
+                       }
+                       return buf.Length;
+               }
+
                // readlink(2)
-               //    int readlink(const char *path, char *buf, size_t bufsize);
+               //    ssize_t readlink(const char *path, char *buf, size_t bufsize);
+               public static int readlink (string path, [Out] StringBuilder buf, ulong bufsiz)
+               {
+                       return ReadlinkIntoStringBuilder (target => readlink (path, target), buf, bufsiz);
+               }
+
+               public static int readlink (string path, [Out] StringBuilder buf)
+               {
+                       return readlink (path, buf, (ulong) buf.Capacity);
+               }
+
                [DllImport (MPH, SetLastError=true,
                                EntryPoint="Mono_Posix_Syscall_readlink")]
-               public static extern int readlink (
+               private static extern long readlink (
                                [MarshalAs (UnmanagedType.CustomMarshaler, MarshalTypeRef=typeof(FileNameMarshaler))]
-                               string path, [Out] StringBuilder buf, ulong bufsiz);
+                               string path, byte[] buf, ulong bufsiz);
 
-               public static int readlink (string path, [Out] StringBuilder buf)
+               public static long readlink (string path, byte[] buf)
                {
-                       return readlink (path, buf, (ulong) buf.Capacity);
+                       return readlink (path, buf, (ulong) buf.LongLength);
                }
 
                [DllImport (LIBC, SetLastError=true)]
@@ -4226,16 +4260,26 @@ namespace Mono.Unix.Native {
                }
 
                // readlinkat(2)
-               //    int readlinkat(int dirfd, const char *pathname, char *buf, size_t bufsize);
+               //    ssize_t readlinkat(int dirfd, const char *pathname, char *buf, size_t bufsize);
+               public static int readlinkat (int dirfd, string pathname, [Out] StringBuilder buf, ulong bufsiz)
+               {
+                       return ReadlinkIntoStringBuilder (target => readlinkat (dirfd, pathname, target), buf, bufsiz);
+               }
+
+               public static int readlinkat (int dirfd, string pathname, [Out] StringBuilder buf)
+               {
+                       return readlinkat (dirfd, pathname, buf, (ulong) buf.Capacity);
+               }
+
                [DllImport (MPH, SetLastError=true,
                                EntryPoint="Mono_Posix_Syscall_readlinkat")]
-               public static extern int readlinkat (int dirfd,
+               private static extern long readlinkat (int dirfd,
                                [MarshalAs (UnmanagedType.CustomMarshaler, MarshalTypeRef=typeof(FileNameMarshaler))]
-                               string pathname, [Out] StringBuilder buf, ulong bufsiz);
+                               string pathname, byte[] buf, ulong bufsiz);
 
-               public static int readlinkat (int dirfd, string pathname, [Out] StringBuilder buf)
+               public static long readlinkat (int dirfd, string pathname, byte[] buf)
                {
-                       return readlinkat (dirfd, pathname, buf, (ulong) buf.Capacity);
+                       return readlinkat (dirfd, pathname, buf, (ulong) buf.LongLength);
                }
 
                [DllImport (LIBC, SetLastError=true)]