Revert "preprocessor/58580 - preprocessor goes OOM with warning for zero literals"

This reverts commit fc3eff8854861fcd70d33d26095b17fe456fae31.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@204490 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 27 insertions, 88 deletions

diff --git a/gcc/input.c b/gcc/input.c
index cb3a0a09f33..a141a92cac3 100644
--- a/gcc/input.c
+++ b/gcc/input.c
@@ -87,114 +87,53 @@ expand_location_1 (source_location loc,
   return xloc;
 }
 
-/* This function reads a line that might contain bytes whose value is
-   zero.  It returns the number of bytes read.  The 'end-of-line'
-   character found at the end of the line is not contained in the
-   returned buffer.  Note that this function has been adapted from
-   getline() and _IO_getdelim() GNU C library functions.  It's been
-   duplicated here because the getline() function is not necessarily
-   present on all platforms.
-
-   LINEPTR points to a buffer that is to contain the line read.
-
-   N points to the size of the the LINEPTR buffer.
-
-   FP points to the file to consider.  */
-
-static ssize_t
-get_line (char **lineptr, size_t *n, FILE *fp)
+/* Reads one line from file into a static buffer.  */
+static const char *
+read_line (FILE *file)
 {
-  ssize_t cur_len = 0, len;
-  char buf[16384];
-
-  if (lineptr == NULL || n == NULL)
-    return -1;
+  static char *string;
+  static size_t string_len;
+  size_t pos = 0;
+  char *ptr;
 
-  if (*lineptr == NULL || *n == 0)
+  if (!string_len)
     {
-      *n = 120;
-      *lineptr = XNEWVEC (char, *n);
+      string_len = 200;
+      string = XNEWVEC (char, string_len);
     }
 
-  len = fread (buf, 1, sizeof buf, fp);
-  if (ferror (fp))
-    return -1;
-
-  for (;;)
+  while ((ptr = fgets (string + pos, string_len - pos, file)))
     {
-      size_t needed;
-      char *t = (char*) memchr (buf, '\n', len);
-      if (t != NULL) len = (t - buf);
-      if (__builtin_expect (len >= SSIZE_MAX - cur_len, 0))
-	return -1;
-      needed = cur_len + len + 1;
-      if (needed > *n)
+      size_t len = strlen (string + pos);
+
+      if (string[pos + len - 1] == '\n')
 	{
-	  char *new_lineptr;
-	  if (needed < 2 * *n)
-	    needed = 2 * *n;
-	  new_lineptr = XRESIZEVEC (char, *lineptr, needed);
-	  *lineptr = new_lineptr;
-	  *n = needed;
+	  string[pos + len - 1] = 0;
+	  return string;
 	}
-      memcpy (*lineptr + cur_len, buf, len);
-      cur_len += len;
-      if (t != NULL)
-	break;
-      len = fread (buf, 1, sizeof buf, fp);
-      if (ferror (fp))
-	return -1;
-      if (len == 0)
-	break;
+      pos += len;
+      string = XRESIZEVEC (char, string, string_len * 2);
+      string_len *= 2;
     }
-
-  if (cur_len)
-    (*lineptr)[cur_len] = '\0';
-  return cur_len;
-}
-
-/* Reads one line from FILE into a static buffer.  If LINE_LENGTH is
- *non-null LINE_LENGTH, will be set by this function to the length of
- *the returned line.  Note that the returned line can contain several
- *zero bytes.  Also note that the returned string is allocated in
- *static storage that is going to be re-used by subsequent invocations
- *of read_line.  */
-static const char *
-read_line (FILE *file, int *line_length)
-{
-  static char *string;
-  static size_t string_len;
-  int len;
-
-  len = get_line (&string, &string_len, file);
-  if (line_length)
-    *line_length = len;
-  return len ? string : NULL;
+      
+  return pos ? string : NULL;
 }
 
 /* Return the physical source line that corresponds to xloc in a
    buffer that is statically allocated.  The newline is replaced by
-   the null character.  Note that the line can contain several null
-   characters, so LINE_LEN, if non-null, points to the actual length
-   of the line.  */
+   the null character.  */
 
 const char *
-location_get_source_line (expanded_location xloc,
-			  int *line_len)
+location_get_source_line (expanded_location xloc)
 {
-  const char *buffer = NULL, *ptr;
-  int lines = 0, len = 0;
+  const char *buffer;
+  int lines = 1;
   FILE *stream = xloc.file ? fopen (xloc.file, "r") : NULL;
   if (!stream)
     return NULL;
 
-  while ((ptr = read_line (stream, &len)) && lines < xloc.line)
-    {
-      buffer = ptr;
-      lines++;
-      if (line_len)
-	*line_len = len;
-    }
+  while ((buffer = read_line (stream)) && lines < xloc.line)
+    lines++;
 
   fclose (stream);
   return buffer;