X-Git-Url: http://git.sourceforge.jp/view?a=blobdiff_plain;f=gcc%2Fgcov-io.c;h=6d371cdcddf28048364452a92ae3fc02603eea4b;hb=653d0639db9f426c9cc72bdb620d2d06055af72e;hp=b59521745171524d84a022aaad2ebdc8142a6c21;hpb=ab6a34f2f7b7c7505a1feeeabdf1d87329eb8878;p=pf3gnuchains%2Fgcc-fork.git

diff --git a/gcc/gcov-io.c b/gcc/gcov-io.c
index b5952174517..6d371cdcddf 100644
--- a/gcc/gcov-io.c
+++ b/gcc/gcov-io.c
@@ -1,6 +1,6 @@
 /* File format for coverage information
-   Copyright (C) 1996, 1997, 1998, 2000, 2002,
-   2003  Free Software Foundation, Inc.
+   Copyright (C) 1996, 1997, 1998, 2000, 2002, 2003, 2004, 2005, 2007,
+   2008  Free Software Foundation, Inc.
    Contributed by Bob Manson <manson@cygnus.com>.
    Completely remangled by Nathan Sidwell <nathan@codesourcery.com>.
 
@@ -8,7 +8,7 @@ This file is part of GCC.
 
 GCC 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 2, or (at your option) any later
+Software Foundation; either version 3, or (at your option) any later
 version.
 
 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
@@ -17,113 +17,150 @@ 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 GCC; see the file COPYING.  If not, write to the Free
-Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-02111-1307, USA.  */
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
 
 /* Routines declared in gcov-io.h.  This file should be #included by
    another source file, after having #included gcov-io.h.  */
 
+#if !IN_GCOV
+static void gcov_write_block (unsigned);
+static gcov_unsigned_t *gcov_write_words (unsigned);
+#endif
+static const gcov_unsigned_t *gcov_read_words (unsigned);
+#if !IN_LIBGCOV
+static void gcov_allocate (unsigned);
+#endif
+
+static inline gcov_unsigned_t from_file (gcov_unsigned_t value)
+{
+#if !IN_LIBGCOV
+  if (gcov_var.endian)
+    {
+      value = (value >> 16) | (value << 16);
+      value = ((value & 0xff00ff) << 8) | ((value >> 8) & 0xff00ff);
+    }
+#endif
+  return value;
+}
+
 /* Open a gcov file. NAME is the name of the file to open and MODE
    indicates whether a new file should be created, or an existing file
-   opened for modification. If MODE is >= 0 an existing file will be
-   opened, if possible, and if MODE is <= 0, a new file will be
-   created. Use MODE=0 to attempt to reopen an existing file and then
-   fall back on creating a new one.  Return zero on failure, >0 on
-   opening an existing file and <0 on creating a new one.  */
+   opened. If MODE is >= 0 an existing file will be opened, if
+   possible, and if MODE is <= 0, a new file will be created. Use
+   MODE=0 to attempt to reopen an existing file and then fall back on
+   creating a new one.  If MODE < 0, the file will be opened in
+   read-only mode.  Otherwise it will be opened for modification.
+   Return zero on failure, >0 on opening an existing file and <0 on
+   creating a new one.  */
 
 GCOV_LINKAGE int
+#if IN_LIBGCOV
+gcov_open (const char *name)
+#else
 gcov_open (const char *name, int mode)
+#endif
 {
-  int result = 1;
-  size_t alloc = 1024;
-#if defined (TARGET_HAS_F_SETLKW) && IN_LIBGCOV
+#if IN_LIBGCOV
+  const int mode = 0;
+#endif
+#if GCOV_LOCKED
   struct flock s_flock;
+  int fd;
 
-  s_flock.l_type = F_WRLCK;
   s_flock.l_whence = SEEK_SET;
   s_flock.l_start = 0;
   s_flock.l_len = 0; /* Until EOF.  */
   s_flock.l_pid = getpid ();
 #endif
-  
-  if (gcov_var.file)
-    abort ();
-  gcov_var.position = gcov_var.length = 0;
-  gcov_var.error = gcov_var.modified = 0;
-  if (mode >= 0)
-    gcov_var.file = fopen (name, "r+b");
-  if (!gcov_var.file && mode <= 0)
+
+  gcc_assert (!gcov_var.file);
+  gcov_var.start = 0;
+  gcov_var.offset = gcov_var.length = 0;
+  gcov_var.overread = -1u;
+  gcov_var.error = 0;
+#if !IN_LIBGCOV
+  gcov_var.endian = 0;
+#endif
+#if GCOV_LOCKED
+  if (mode > 0)
     {
-      result = -1;
-      gcov_var.file = fopen (name, "w+b");
+      /* Read-only mode - acquire a read-lock.  */
+      s_flock.l_type = F_RDLCK;
+      fd = open (name, O_RDONLY);
     }
-  if (!gcov_var.file)
+  else
+    {
+      /* Write mode - acquire a write-lock.  */
+      s_flock.l_type = F_WRLCK;
+      fd = open (name, O_RDWR | O_CREAT, 0666);
+    }
+  if (fd < 0)
     return 0;
 
-#if defined (TARGET_HAS_F_SETLKW) && IN_LIBGCOV
-  while (fcntl (fileno (gcov_var.file), F_SETLKW, &s_flock)
-	 && errno == EINTR)
+  while (fcntl (fd, F_SETLKW, &s_flock) && errno == EINTR)
     continue;
-#endif
 
-  if (result >= 0)
+  gcov_var.file = fdopen (fd, (mode > 0) ? "rb" : "r+b");
+
+  if (!gcov_var.file)
     {
-      if (fseek (gcov_var.file, 0, SEEK_END))
-	{
-	  fclose (gcov_var.file);
-	  gcov_var.file = 0;
-	  return 0;
-	}
-      gcov_var.length = ftell (gcov_var.file);
-      fseek (gcov_var.file, 0, SEEK_SET);
-      alloc += gcov_var.length;
+      close (fd);
+      return 0;
     }
-  if (alloc > gcov_var.alloc)
+
+  if (mode > 0)
+    gcov_var.mode = 1;
+  else if (mode == 0)
     {
-      if (gcov_var.buffer)
-	free (gcov_var.buffer);
-      gcov_var.alloc = alloc;
-#if IN_LIBGCOV
-      gcov_var.buffer = malloc (gcov_var.alloc);
-      if (!gcov_var.buffer)
+      struct stat st;
+
+      if (fstat (fd, &st) < 0)
 	{
 	  fclose (gcov_var.file);
 	  gcov_var.file = 0;
-	  gcov_var.length = 0;
-	  gcov_var.alloc = 0;
 	  return 0;
 	}
-#else
-      gcov_var.buffer = xmalloc (gcov_var.alloc);
-#endif
+      if (st.st_size != 0)
+	gcov_var.mode = 1;
+      else
+	gcov_var.mode = mode * 2 + 1;
     }
-  if (result >= 0
-      && fread (gcov_var.buffer, gcov_var.length, 1, gcov_var.file) != 1)
+  else
+    gcov_var.mode = mode * 2 + 1;
+#else
+  if (mode >= 0)
+    gcov_var.file = fopen (name, (mode > 0) ? "rb" : "r+b");
+
+  if (gcov_var.file)
+    gcov_var.mode = 1;
+  else if (mode <= 0)
     {
-      fclose (gcov_var.file);
-      gcov_var.file = 0;
-      gcov_var.length = 0;
-      return 0;
+      gcov_var.file = fopen (name, "w+b");
+      if (gcov_var.file)
+	gcov_var.mode = mode * 2 + 1;
     }
-  return result;
+  if (!gcov_var.file)
+    return 0;
+#endif
+
+  setbuf (gcov_var.file, (char *)0);
+
+  return 1;
 }
 
 /* Close the current gcov file. Flushes data to disk. Returns nonzero
    on failure or error flag set.  */
 
 GCOV_LINKAGE int
-gcov_close ()
+gcov_close (void)
 {
-  int result = 0;
-  
   if (gcov_var.file)
     {
-      if (gcov_var.modified
-	  && (fseek (gcov_var.file, 0, SEEK_SET)
-	      || fwrite (gcov_var.buffer, gcov_var.length,
-			 1, gcov_var.file) != 1))
-	result = 1;
+#if !IN_GCOV
+      if (gcov_var.offset && gcov_var.mode < 0)
+	gcov_write_block (gcov_var.offset);
+#endif
       fclose (gcov_var.file);
       gcov_var.file = 0;
       gcov_var.length = 0;
@@ -133,47 +170,85 @@ gcov_close ()
   gcov_var.alloc = 0;
   gcov_var.buffer = 0;
 #endif
-  return result ? 1 : gcov_var.error;
+  gcov_var.mode = 0;
+  return gcov_var.error;
+}
+
+#if !IN_LIBGCOV
+/* Check if MAGIC is EXPECTED. Use it to determine endianness of the
+   file. Returns +1 for same endian, -1 for other endian and zero for
+   not EXPECTED.  */
+
+GCOV_LINKAGE int
+gcov_magic (gcov_unsigned_t magic, gcov_unsigned_t expected)
+{
+  if (magic == expected)
+    return 1;
+  magic = (magic >> 16) | (magic << 16);
+  magic = ((magic & 0xff00ff) << 8) | ((magic >> 8) & 0xff00ff);
+  if (magic == expected)
+    {
+      gcov_var.endian = 1;
+      return -1;
+    }
+  return 0;
+}
+#endif
+
+#if !IN_LIBGCOV
+static void
+gcov_allocate (unsigned length)
+{
+  size_t new_size = gcov_var.alloc;
+
+  if (!new_size)
+    new_size = GCOV_BLOCK_SIZE;
+  new_size += length;
+  new_size *= 2;
+
+  gcov_var.alloc = new_size;
+  gcov_var.buffer = XRESIZEVAR (gcov_unsigned_t, gcov_var.buffer, new_size << 2);
 }
+#endif
 
 #if !IN_GCOV
+/* Write out the current block, if needs be.  */
+
+static void
+gcov_write_block (unsigned size)
+{
+  if (fwrite (gcov_var.buffer, size << 2, 1, gcov_var.file) != 1)
+    gcov_var.error = 1;
+  gcov_var.start += size;
+  gcov_var.offset -= size;
+}
+
 /* Allocate space to write BYTES bytes to the gcov file. Return a
    pointer to those bytes, or NULL on failure.  */
 
-GCOV_LINKAGE unsigned char *
-gcov_write_bytes (unsigned bytes)
+static gcov_unsigned_t *
+gcov_write_words (unsigned words)
 {
-  char unsigned *result;
-
-  if (gcov_var.position + bytes > gcov_var.alloc)
-    {
-      size_t new_size = (gcov_var.alloc + bytes) * 3 / 2;
+  gcov_unsigned_t *result;
 
-      if (!gcov_var.buffer)
-	return 0;
+  gcc_assert (gcov_var.mode < 0);
 #if IN_LIBGCOV
-      result = realloc (gcov_var.buffer, new_size);
-      if (!result)
+  if (gcov_var.offset >= GCOV_BLOCK_SIZE)
+    {
+      gcov_write_block (GCOV_BLOCK_SIZE);
+      if (gcov_var.offset)
 	{
-	  free (gcov_var.buffer);
-	  gcov_var.buffer = 0;
-	  gcov_var.alloc = 0;
-	  gcov_var.position = gcov_var.length = 0;
-	  gcov_var.error = 1;
-	  return 0;
+	  gcc_assert (gcov_var.offset == 1);
+	  memcpy (gcov_var.buffer, gcov_var.buffer + GCOV_BLOCK_SIZE, 4);
 	}
+    }
 #else
-      result = xrealloc (gcov_var.buffer, new_size);
+  if (gcov_var.offset + words > gcov_var.alloc)
+    gcov_allocate (gcov_var.offset + words);
 #endif
-      gcov_var.alloc = new_size;
-      gcov_var.buffer = result;
-    }
-  
-  result = &gcov_var.buffer[gcov_var.position];
-  gcov_var.position += bytes;
-  gcov_var.modified = 1;
-  if (gcov_var.position > gcov_var.length)
-    gcov_var.length = gcov_var.position;
+  result = &gcov_var.buffer[gcov_var.offset];
+  gcov_var.offset += words;
+
   return result;
 }
 
@@ -181,22 +256,11 @@ gcov_write_bytes (unsigned bytes)
    appropriately.  */
 
 GCOV_LINKAGE void
-gcov_write_unsigned (unsigned value)
+gcov_write_unsigned (gcov_unsigned_t value)
 {
-  unsigned char *buffer = gcov_write_bytes (4);
-  unsigned ix;
+  gcov_unsigned_t *buffer = gcov_write_words (1);
 
-  if (!buffer)
-    return;
-  for (ix = 4; ix--; )
-    {
-      buffer[ix] = value;
-      value >>= 8;
-    }
-  if (sizeof (value) > 4 && value)
-    gcov_var.error = -1;
-
-  return;
+  buffer[0] = value;
 }
 
 /* Write counter VALUE to coverage file.  Sets error flag
@@ -206,22 +270,17 @@ gcov_write_unsigned (unsigned value)
 GCOV_LINKAGE void
 gcov_write_counter (gcov_type value)
 {
-  unsigned char *buffer = gcov_write_bytes (8);
-  unsigned ix;
+  gcov_unsigned_t *buffer = gcov_write_words (2);
 
-  if (!buffer)
-    return;
-  for (ix = 8; ix--; )
-    {
-      buffer[ix] = value;
-      value >>= 8;
-    }
-  if ((sizeof (value) > 8 && value) || value < 0)
-    gcov_var.error = -1;
-  return;
+  buffer[0] = (gcov_unsigned_t) value;
+  if (sizeof (value) > sizeof (gcov_unsigned_t))
+    buffer[1] = (gcov_unsigned_t) (value >> 32);
+  else
+    buffer[1] = 0;
 }
 #endif /* IN_LIBGCOV */
 
+#if !IN_LIBGCOV
 /* Write STRING to coverage file.  Sets error flag on file
    error, overflow flag on overflow */
 
@@ -229,50 +288,36 @@ GCOV_LINKAGE void
 gcov_write_string (const char *string)
 {
   unsigned length = 0;
-  unsigned pad = 0;
-  unsigned rem = 0;
-  unsigned char *buffer;
+  unsigned alloc = 0;
+  gcov_unsigned_t *buffer;
 
   if (string)
     {
       length = strlen (string);
-      rem = 4 - (length & 3);
-    }
-  
-  buffer = gcov_write_bytes (4 + length + rem);
-  if (buffer)
-    {
-      unsigned ix;
-      unsigned value = length;
-      
-      for (ix = 4; ix--; )
-	{
-	  buffer[ix] = value;
-	  value >>= 8;
-	}
-      memcpy (buffer + 4, string, length);
-      memcpy (buffer + 4 + length, &pad, rem);
+      alloc = (length + 4) >> 2;
     }
+
+  buffer = gcov_write_words (1 + alloc);
+
+  buffer[0] = alloc;
+  buffer[alloc] = 0;
+  memcpy (&buffer[1], string, length);
 }
+#endif
 
+#if !IN_LIBGCOV
 /* Write a tag TAG and reserve space for the record length. Return a
    value to be used for gcov_write_length.  */
 
-GCOV_LINKAGE unsigned long
-gcov_write_tag (unsigned tag)
+GCOV_LINKAGE gcov_position_t
+gcov_write_tag (gcov_unsigned_t tag)
 {
-  unsigned long result = gcov_var.position;
-  unsigned char *buffer = gcov_write_bytes (8);
-  unsigned ix;
+  gcov_position_t result = gcov_var.start + gcov_var.offset;
+  gcov_unsigned_t *buffer = gcov_write_words (2);
+
+  buffer[0] = tag;
+  buffer[1] = 0;
 
-  if (!buffer)
-    return 0;
-  for (ix = 4; ix--; )
-    {
-      buffer[ix] = tag;
-      tag >>= 8;
-    }
-  memset (buffer + 4, 0, 4);
   return result;
 }
 
@@ -282,36 +327,48 @@ gcov_write_tag (unsigned tag)
    overflow.  */
 
 GCOV_LINKAGE void
-gcov_write_length (unsigned long position)
+gcov_write_length (gcov_position_t position)
 {
-  if (position)
-    {
-      unsigned length = gcov_var.position - position - 8;
-      unsigned char *buffer = &gcov_var.buffer[position + 4];
-      unsigned ix;
-      
-      for (ix = 4; ix--; )
-	{
-	  buffer[ix] = length;
-	  length >>= 8;
-	}
-    }
+  unsigned offset;
+  gcov_unsigned_t length;
+  gcov_unsigned_t *buffer;
+
+  gcc_assert (gcov_var.mode < 0);
+  gcc_assert (position + 2 <= gcov_var.start + gcov_var.offset);
+  gcc_assert (position >= gcov_var.start);
+  offset = position - gcov_var.start;
+  length = gcov_var.offset - offset - 2;
+  buffer = (gcov_unsigned_t *) &gcov_var.buffer[offset];
+  buffer[1] = length;
+  if (gcov_var.offset >= GCOV_BLOCK_SIZE)
+    gcov_write_block (gcov_var.offset);
 }
 
-#if IN_LIBGCOV
-/* Write a summary structure to the gcov file.  Return non-zero on
+#else /* IN_LIBGCOV */
+
+/* Write a tag TAG and length LENGTH.  */
+
+GCOV_LINKAGE void
+gcov_write_tag_length (gcov_unsigned_t tag, gcov_unsigned_t length)
+{
+  gcov_unsigned_t *buffer = gcov_write_words (2);
+
+  buffer[0] = tag;
+  buffer[1] = length;
+}
+
+/* Write a summary structure to the gcov file.  Return nonzero on
    overflow.  */
 
 GCOV_LINKAGE void
-gcov_write_summary (unsigned tag, const struct gcov_summary *summary)
+gcov_write_summary (gcov_unsigned_t tag, const struct gcov_summary *summary)
 {
   unsigned ix;
   const struct gcov_ctr_summary *csum;
-  unsigned long base;
 
-  base = gcov_write_tag (tag);
+  gcov_write_tag_length (tag, GCOV_TAG_SUMMARY_LENGTH);
   gcov_write_unsigned (summary->checksum);
-  for (csum = summary->ctrs, ix = GCOV_COUNTERS; ix--; csum++)
+  for (csum = summary->ctrs, ix = GCOV_COUNTERS_SUMMABLE; ix--; csum++)
     {
       gcov_write_unsigned (csum->num);
       gcov_write_unsigned (csum->runs);
@@ -319,51 +376,70 @@ gcov_write_summary (unsigned tag, const struct gcov_summary *summary)
       gcov_write_counter (csum->run_max);
       gcov_write_counter (csum->sum_max);
     }
-  gcov_write_length (base);
 }
 #endif /* IN_LIBGCOV */
 
 #endif /*!IN_GCOV */
 
 /* Return a pointer to read BYTES bytes from the gcov file. Returns
-   NULL on failure (read past EOF). */
+   NULL on failure (read past EOF).  */
 
-GCOV_LINKAGE const unsigned char *
-gcov_read_bytes (unsigned bytes)
+static const gcov_unsigned_t *
+gcov_read_words (unsigned words)
 {
-  const unsigned char *result;
-  
-  if (gcov_var.position + bytes > gcov_var.length)
+  const gcov_unsigned_t *result;
+  unsigned excess = gcov_var.length - gcov_var.offset;
+
+  gcc_assert (gcov_var.mode > 0);
+  if (excess < words)
     {
-      gcov_var.error = 1;
-      return 0;
+      gcov_var.start += gcov_var.offset;
+#if IN_LIBGCOV
+      if (excess)
+	{
+	  gcc_assert (excess == 1);
+	  memcpy (gcov_var.buffer, gcov_var.buffer + gcov_var.offset, 4);
+	}
+#else
+      memmove (gcov_var.buffer, gcov_var.buffer + gcov_var.offset, excess * 4);
+#endif
+      gcov_var.offset = 0;
+      gcov_var.length = excess;
+#if IN_LIBGCOV
+      gcc_assert (!gcov_var.length || gcov_var.length == 1);
+      excess = GCOV_BLOCK_SIZE;
+#else
+      if (gcov_var.length + words > gcov_var.alloc)
+	gcov_allocate (gcov_var.length + words);
+      excess = gcov_var.alloc - gcov_var.length;
+#endif
+      excess = fread (gcov_var.buffer + gcov_var.length,
+		      1, excess << 2, gcov_var.file) >> 2;
+      gcov_var.length += excess;
+      if (gcov_var.length < words)
+	{
+	  gcov_var.overread += words - gcov_var.length;
+	  gcov_var.length = 0;
+	  return 0;
+	}
     }
-  
-  result = &gcov_var.buffer[gcov_var.position];
-  gcov_var.position += bytes;
+  result = &gcov_var.buffer[gcov_var.offset];
+  gcov_var.offset += words;
   return result;
 }
 
 /* Read unsigned value from a coverage file. Sets error flag on file
    error, overflow flag on overflow */
 
-GCOV_LINKAGE unsigned
-gcov_read_unsigned ()
+GCOV_LINKAGE gcov_unsigned_t
+gcov_read_unsigned (void)
 {
-  unsigned value = 0;
-  unsigned ix;
-  const unsigned char *buffer = gcov_read_bytes (4);
+  gcov_unsigned_t value;
+  const gcov_unsigned_t *buffer = gcov_read_words (1);
 
   if (!buffer)
     return 0;
-  for (ix = sizeof (value); ix < 4; ix++)
-    if (buffer[ix])
-      gcov_var.error = -1;
-  for (ix = 0; ix != 4; ix++)
-    {
-      value <<= 8;
-      value |= buffer[ix];
-    }
+  value = from_file (buffer[0]);
   return value;
 }
 
@@ -371,24 +447,19 @@ gcov_read_unsigned ()
    error, overflow flag on overflow */
 
 GCOV_LINKAGE gcov_type
-gcov_read_counter ()
+gcov_read_counter (void)
 {
-  gcov_type value = 0;
-  unsigned ix;
-  const unsigned char *buffer = gcov_read_bytes (8);
+  gcov_type value;
+  const gcov_unsigned_t *buffer = gcov_read_words (2);
 
   if (!buffer)
     return 0;
-  for (ix = sizeof (value); ix < 8; ix++)
-    if (buffer[ix])
-      gcov_var.error = -1;
-  for (ix = 0; ix != 8; ix++)
-    {
-      value <<= 8;
-      value |= buffer[ix];
-    }
-  if (value < 0)
+  value = from_file (buffer[0]);
+  if (sizeof (value) > sizeof (gcov_unsigned_t))
+    value |= ((gcov_type) from_file (buffer[1])) << 32;
+  else if (buffer[1])
     gcov_var.error = -1;
+
   return value;
 }
 
@@ -396,26 +467,27 @@ gcov_read_counter ()
    buffer, or NULL on empty string. You must copy the string before
    calling another gcov function.  */
 
+#if !IN_LIBGCOV
 GCOV_LINKAGE const char *
-gcov_read_string ()
+gcov_read_string (void)
 {
   unsigned length = gcov_read_unsigned ();
-  
+
   if (!length)
     return 0;
 
-  length += 4 - (length & 3);
-  return (const char *) gcov_read_bytes (length);
+  return (const char *) gcov_read_words (length);
 }
+#endif
 
 GCOV_LINKAGE void
 gcov_read_summary (struct gcov_summary *summary)
 {
   unsigned ix;
   struct gcov_ctr_summary *csum;
-  
+
   summary->checksum = gcov_read_unsigned ();
-  for (csum = summary->ctrs, ix = GCOV_COUNTERS; ix--; csum++)
+  for (csum = summary->ctrs, ix = GCOV_COUNTERS_SUMMABLE; ix--; csum++)
     {
       csum->num = gcov_read_unsigned ();
       csum->runs = gcov_read_unsigned ();
@@ -425,14 +497,48 @@ gcov_read_summary (struct gcov_summary *summary)
     }
 }
 
+#if !IN_LIBGCOV
+/* Reset to a known position.  BASE should have been obtained from
+   gcov_position, LENGTH should be a record length.  */
+
+GCOV_LINKAGE void
+gcov_sync (gcov_position_t base, gcov_unsigned_t length)
+{
+  gcc_assert (gcov_var.mode > 0);
+  base += length;
+  if (base - gcov_var.start <= gcov_var.length)
+    gcov_var.offset = base - gcov_var.start;
+  else
+    {
+      gcov_var.offset = gcov_var.length = 0;
+      fseek (gcov_var.file, base << 2, SEEK_SET);
+      gcov_var.start = ftell (gcov_var.file) >> 2;
+    }
+}
+#endif
+
+#if IN_LIBGCOV
+/* Move to a given position in a gcov file.  */
+
+GCOV_LINKAGE void
+gcov_seek (gcov_position_t base)
+{
+  gcc_assert (gcov_var.mode < 0);
+  if (gcov_var.offset)
+    gcov_write_block (gcov_var.offset);
+  fseek (gcov_var.file, base << 2, SEEK_SET);
+  gcov_var.start = ftell (gcov_var.file) >> 2;
+}
+#endif
+
 #if IN_GCOV > 0
 /* Return the modification time of the current gcov file.  */
 
 GCOV_LINKAGE time_t
-gcov_time ()
+gcov_time (void)
 {
   struct stat status;
-  
+
   if (fstat (fileno (gcov_var.file), &status))
     return 0;
   else