Add ungetc and re-indent _io.rs.

Author: graydon

src/lib/_io.rs

@@ -5,150 +5,154 @@ import std._vec;
 
 type stdio_reader = unsafe obj {
                            fn getc() -> int;
+                           fn ungetc(int i);
 };
 
 fn new_stdio_reader(str path) -> stdio_reader {
-  unsafe obj stdio_FILE_reader(os.libc.FILE f) {
-    fn getc() -> int {
-      ret os.libc.fgetc(f);
-    }
-    drop {
-      os.libc.fclose(f);
+    unsafe obj stdio_FILE_reader(os.libc.FILE f) {
+        fn getc() -> int {
+            ret os.libc.fgetc(f);
+        }
+        fn ungetc(int i) {
+            os.libc.ungetc(i, f);
+        }
+        drop {
+            os.libc.fclose(f);
+        }
     }
-  }
-  ret stdio_FILE_reader(os.libc.fopen(_str.buf(path),
-                                      _str.buf("r")));
+    ret stdio_FILE_reader(os.libc.fopen(_str.buf(path),
+                                        _str.buf("r")));
 }
 
 
 type buf_reader = unsafe obj {
-  fn read() -> vec[u8];
+                         fn read() -> vec[u8];
 };
 
 type buf_writer = unsafe obj {
-  fn write(vec[u8] v);
+                         fn write(vec[u8] v);
 };
 
 fn default_bufsz() -> uint {
-  ret 4096u;
+    ret 4096u;
 }
 
 fn new_buf() -> vec[u8] {
-  ret _vec.alloc[u8](default_bufsz());
+    ret _vec.alloc[u8](default_bufsz());
 }
 
 fn new_buf_reader(str path) -> buf_reader {
 
-  unsafe obj fd_buf_reader(int fd, mutable vec[u8] buf) {
+    unsafe obj fd_buf_reader(int fd, mutable vec[u8] buf) {
 
-    fn read() -> vec[u8] {
+        fn read() -> vec[u8] {
 
-      // Ensure our buf is singly-referenced.
-      if (_vec.rustrt.refcount[u8](buf) != 1u) {
-        buf = new_buf();
-      }
+            // Ensure our buf is singly-referenced.
+            if (_vec.rustrt.refcount[u8](buf) != 1u) {
+                buf = new_buf();
+            }
 
-      auto len = default_bufsz();
-      auto vbuf = _vec.buf[u8](buf);
-      auto count = os.libc.read(fd, vbuf, len);
+            auto len = default_bufsz();
+            auto vbuf = _vec.buf[u8](buf);
+            auto count = os.libc.read(fd, vbuf, len);
 
-      if (count < 0) {
-        log "error filling buffer";
-        log sys.rustrt.last_os_error();
-        fail;
-      }
+            if (count < 0) {
+                log "error filling buffer";
+                log sys.rustrt.last_os_error();
+                fail;
+            }
+
+            _vec.len_set[u8](buf, count as uint);
+            ret buf;
+        }
 
-      _vec.len_set[u8](buf, count as uint);
-      ret buf;
+        drop {
+            os.libc.close(fd);
+        }
     }
 
-    drop {
-      os.libc.close(fd);
+    auto fd = os.libc.open(_str.buf(path),
+                           os.libc_constants.O_RDONLY() |
+                           os.libc_constants.O_BINARY(),
+                           0u);
+
+    if (fd < 0) {
+        log "error opening file for reading";
+        log sys.rustrt.last_os_error();
+        fail;
     }
-  }
-
-  auto fd = os.libc.open(_str.buf(path),
-                         os.libc_constants.O_RDONLY() |
-                         os.libc_constants.O_BINARY(),
-                         0u);
-
-  if (fd < 0) {
-    log "error opening file for reading";
-    log sys.rustrt.last_os_error();
-    fail;
-  }
-  ret fd_buf_reader(fd, new_buf());
+    ret fd_buf_reader(fd, new_buf());
 }
 
 type fileflag = tag(append(), create(), truncate());
 
 fn new_buf_writer(str path, vec[fileflag] flags) -> buf_writer {
 
-  unsafe obj fd_buf_writer(int fd) {
-
-    fn write(vec[u8] v) {
-      auto len = _vec.len[u8](v);
-      auto count = 0u;
-      auto vbuf;
-      while (count < len) {
-        vbuf = _vec.buf_off[u8](v, count);
-        auto nout = os.libc.write(fd, vbuf, len);
-        if (nout < 0) {
-          log "error dumping buffer";
-          log sys.rustrt.last_os_error();
-          fail;
+    unsafe obj fd_buf_writer(int fd) {
+
+        fn write(vec[u8] v) {
+            auto len = _vec.len[u8](v);
+            auto count = 0u;
+            auto vbuf;
+            while (count < len) {
+                vbuf = _vec.buf_off[u8](v, count);
+                auto nout = os.libc.write(fd, vbuf, len);
+                if (nout < 0) {
+                    log "error dumping buffer";
+                    log sys.rustrt.last_os_error();
+                    fail;
+                }
+                count += nout as uint;
+            }
+        }
+
+        drop {
+            os.libc.close(fd);
         }
-        count += nout as uint;
-      }
     }
 
-    drop {
-      os.libc.close(fd);
+    let int fflags =
+        os.libc_constants.O_WRONLY() |
+        os.libc_constants.O_BINARY();
+
+    for (fileflag f in flags) {
+        alt (f) {
+            case (append())   { fflags |= os.libc_constants.O_APPEND(); }
+            case (create())   { fflags |= os.libc_constants.O_CREAT(); }
+            case (truncate()) { fflags |= os.libc_constants.O_TRUNC(); }
+        }
     }
-  }
 
-  let int fflags =
-    os.libc_constants.O_WRONLY() |
-    os.libc_constants.O_BINARY();
+    auto fd = os.libc.open(_str.buf(path),
+                           fflags,
+                           os.libc_constants.S_IRUSR() |
+                           os.libc_constants.S_IWUSR());
 
-  for (fileflag f in flags) {
-    alt (f) {
-      case (append())   { fflags |= os.libc_constants.O_APPEND(); }
-      case (create())   { fflags |= os.libc_constants.O_CREAT(); }
-      case (truncate()) { fflags |= os.libc_constants.O_TRUNC(); }
+    if (fd < 0) {
+        log "error opening file for writing";
+        log sys.rustrt.last_os_error();
+        fail;
     }
-  }
-
-  auto fd = os.libc.open(_str.buf(path),
-                         fflags,
-                         os.libc_constants.S_IRUSR() |
-                         os.libc_constants.S_IWUSR());
-
-  if (fd < 0) {
-    log "error opening file for writing";
-    log sys.rustrt.last_os_error();
-    fail;
-  }
-  ret fd_buf_writer(fd);
+    ret fd_buf_writer(fd);
 }
 
 type writer =
-  unsafe obj {
-    fn write_str(str s);
-    fn write_int(int n);
-    fn write_uint(uint n);
-  };
+    unsafe obj {
+           fn write_str(str s);
+           fn write_int(int n);
+           fn write_uint(uint n);
+    };
 
 fn file_writer(str path,
                vec[fileflag] flags)
-  -> writer
+    -> writer
 {
-  unsafe obj fw(buf_writer out) {
-    fn write_str(str s)   { out.write(_str.bytes(s)); }
-    fn write_int(int n)   { out.write(_str.bytes(_int.to_str(n, 10u))); }
-    fn write_uint(uint n) { out.write(_str.bytes(_uint.to_str(n, 10u))); }
-  }
-  ret fw(new_buf_writer(path, flags));
+    unsafe obj fw(buf_writer out) {
+        fn write_str(str s)   { out.write(_str.bytes(s)); }
+        fn write_int(int n)   { out.write(_str.bytes(_int.to_str(n, 10u))); }
+        fn write_uint(uint n) { out.write(_str.bytes(_uint.to_str(n, 10u))); }
+    }
+    ret fw(new_buf_writer(path, flags));
 }
 
 //

src/lib/linux_os.rs

@@ -12,6 +12,7 @@ native mod libc = "libc.so.6" {
   fn fopen(sbuf path, sbuf mode) -> FILE;
   fn fclose(FILE f);
   fn fgetc(FILE f) -> int;
+  fn ungetc(int c, FILE f);
 
   type dir;
   // readdir is a mess; handle via wrapper function in rustrt.

src/lib/macos_os.rs

@@ -12,6 +12,7 @@ native mod libc = "libc.dylib" {
   fn fopen(sbuf path, sbuf mode) -> FILE;
   fn fclose(FILE f);
   fn fgetc(FILE f) -> int;
+  fn ungetc(int c, FILE f);
 
   type dir;
   // readdir is a mess; handle via wrapper function in rustrt.

src/lib/win32_os.rs

@@ -11,6 +11,7 @@ native mod libc = "msvcrt.dll" {
   fn fopen(sbuf path, sbuf mode) -> FILE;
   fn fclose(FILE f);
   fn fgetc(FILE f) -> int;
+  fn ungetc(int c, FILE f);
 }
 
 mod libc_constants {