* libio/fileops.c (_IO_file_sync_mmap): New function.

	(_IO_file_jumps_mmap): Use it.
	(_IO_file_underflow_mmap): Rewritten.  If after EOF or fflush,
	repeat the stat check and resize the mapped buffer as necessary.

2002-07-31  Roland McGrath  <roland@frob.com>

	* libio/fileops.c (decide_maybe_mmap): New static function.
	Code taken from libio/iofopen.c:__fopen_maybe_mmap to try to
	mmap the file contents.  Then switch the jump tables to the mmap
	tables if it worked, or the vanilla file tables if not.
	(_IO_file_underflow_maybe_mmap): New function.
	(_IO_file_seekoff_maybe_mmap): New function.
	(_IO_file_xsgetn_maybe_mmap): New function.
	(_IO_file_jumps_maybe_mmap): New variable, jump table using those.
	* libio/libioP.h: Declare those.
	* libio/wfileops.c (_IO_wfile_underflow_maybe_mmap): New function.
	(_IO_wfile_jumps_maybe_mmap): New variable, jump table using that.
	* libio/iofopen.c (__fopen_maybe_mmap): Don't try to mmap here.
	If the stream is read-only, set its jump tables to those new ones.
	* libio/iofdopen.c (_IO_new_fdopen) [_G_HAVE_MMAP]: Set the initial
	jump tables to the maybe_mmap ones, and don't call __fopen_maybe_mmap.
	We need the tables set before _IO_file_attach.

	* libio/tst-mmap-eofsync.c: New file.
	* libio/tst-mmap-fflushsync.c: New file.
	* libio/bug-mmap-fflush.c: New file.
	* libio/tst-mmap2-eofsync.c: New file.
	* libio/Makefile (tests): Add them.

	* libio/wfileops.c (_IO_wfile_underflow_mmap): Don't set EOF bit when
	_IO_file_underflow_mmap fails, it already set the appropriate bit.

1 files changed, 106 insertions, 0 deletions

diff --git a/libio/tst-mmap-eofsync.c b/libio/tst-mmap-eofsync.c
new file mode 100644
index 0000000..909e868
--- /dev/null
+++ b/libio/tst-mmap-eofsync.c
@@ -0,0 +1,106 @@
+/* Test program for synchronization of stdio state with file after EOF.  */
+
+#include <stdio.h>
+#include <error.h>
+#include <errno.h>
+
+static void do_prepare (void);
+#define PREPARE(argc, argv) do_prepare ()
+static int do_test (void);
+#define TEST_FUNCTION do_test ()
+#include <test-skeleton.c>
+
+static char *temp_file;
+static int temp_fd;
+
+static char text1[] = "Line the first\n";
+static char text2[] = "Line the second\n";
+
+static void
+do_prepare (void)
+{
+  temp_fd = create_temp_file ("tst-mmap-eofsync.", &temp_file);
+  if (temp_fd == -1)
+    error (1, errno, "cannot create temporary file");
+  else
+    {
+      ssize_t cc = write (temp_fd, text1, sizeof text1 - 1);
+      if (cc != sizeof text1 - 1)
+	error (1, errno, "cannot write to temporary file");
+    }
+}
+
+static int
+do_test (void)
+{
+  FILE *f;
+  char buf[128];
+  int result = 0;
+  int c;
+
+  f = fopen (temp_file, "r");
+  if (f == NULL)
+    {
+      perror (temp_file);
+      return 1;
+    }
+
+  if (fgets (buf, sizeof buf, f) == NULL)
+    {
+      perror ("fgets");
+      return 1;
+    }
+
+  if (strcmp (buf, text1))
+    {
+      printf ("read \"%s\", expected \"%s\"\n", buf, text1);
+      result = 1;
+    }
+
+  printf ("feof = %d, ferror = %d immediately after fgets\n",
+	  feof (f), ferror (f));
+
+#if 1
+  c = fgetc (f);
+  if (c == EOF)
+    printf ("fgetc -> EOF (feof = %d, ferror = %d)\n",
+	    feof (f), ferror (f));
+  else
+    {
+      printf ("fgetc returned %o (feof = %d, ferror = %d)\n",
+	      c, feof (f), ferror (f));
+      result = 1;
+    }
+#endif
+
+  c = write (temp_fd, text2, sizeof text2 - 1);
+  if (c == sizeof text2 - 1)
+    printf ("wrote more to file\n");
+  else
+    {
+      printf ("wrote %d != %d (%m)\n", c, sizeof text2 - 1);
+      result = 1;
+    }
+
+  if (fgets (buf, sizeof buf, f) == NULL)
+    {
+      printf ("second fgets fails: feof = %d, ferror = %d (%m)\n",
+	      feof (f), ferror (f));
+      clearerr (f);
+      if (fgets (buf, sizeof buf, f) == NULL)
+	{
+	  printf ("retry fgets fails: feof = %d, ferror = %d (%m)\n",
+		  feof (f), ferror (f));
+	  result = 1;
+	}
+    }
+  if (result == 0 && strcmp (buf, text2))
+    {
+      printf ("second time read \"%s\", expected \"%s\"\n", buf, text2);
+      result = 1;
+    }
+
+  fclose (f);
+
+  return result;
+}