-/* Read a line from FP. The function reallocs the storage as needed
- to accomodate for any length of the line. Reallocs are done
- storage exponentially, doubling the storage after each overflow to
- minimize the number of calls to realloc() and fgets(). The newline
- character at the end of line is retained.
-
- After end-of-file is encountered without anything being read, NULL
- is returned. NULL is also returned on error. To distinguish
- between these two cases, use the stdio function ferror(). */
-
-char *
-read_whole_line (FILE *fp)
-{
- int length = 0;
- int bufsize = 81;
- char *line = xmalloc (bufsize);
-
- while (fgets (line + length, bufsize - length, fp))
- {
- length += strlen (line + length);
- assert (length > 0);
- if (line[length - 1] == '\n')
- break;
- /* fgets() guarantees to read the whole line, or to use up the
- space we've given it. We can double the buffer
- unconditionally. */
- bufsize <<= 1;
- line = xrealloc (line, bufsize);
- }
- if (length == 0 || ferror (fp))
- {
- xfree (line);
- return NULL;
- }
- if (length + 1 < bufsize)
- /* Relieve the memory from our exponential greediness. We say
- `length + 1' because the terminating \0 is not included in
- LENGTH. We don't need to zero-terminate the string ourselves,
- though, because fgets() does that. */
- line = xrealloc (line, length + 1);
- return line;
-}