| The speed-relevant code is only the case for INPUT_CHAIN. I added the one
| for INPUT_STRING because it may be useful it situations I don't know of.
And here is, for completeness, the handling of INPUT_FILE. It requires the
modules freadahead, freadptr, freadseek from gnulib. No speed improvement
measureable with autoconf.
*** input.c.patch11 2008-02-28 14:52:02.000000000 +0100
--- input.c 2008-02-29 01:53:41.000000000 +0100
***************
*** 60,65 ****
--- 60,69 ----
swapping between input blocks updates the global variables
accordingly. */
+ #include "freadahead.h"
+ #include "freadptr.h"
+ #include "freadseek.h"
+
#ifdef ENABLE_CHANGEWORD
# include "regex.h"
#endif /* ENABLE_CHANGEWORD */
***************
*** 1733,1738 ****
--- 1737,1799 ----
continue;
}
}
+ else if (isp->type == INPUT_FILE)
+ {
+ if (!isp->u.u_f.end)
+ {
+ size_t n = freadahead (isp->u.u_f.fp);
+ if (n > 0)
+ {
+ const char *readptr = freadptr (isp->u.u_f.fp);
+ if (readptr != NULL)
+ {
+ unsigned char curr_quote_1 =
+ to_uchar (curr_quote.str1[0]);
+ unsigned char curr_quote_2 =
+ to_uchar (curr_quote.str2[0]);
+ const char *p = readptr;
+ size_t count;
+
+ do
+ {
+ unsigned char ch;
+
+ if (start_of_input_line)
+ {
+ start_of_input_line = false;
+ current_line = ++isp->line;
+ }
+ ch = to_uchar (*p);
+ if (ch == '\n')
+ start_of_input_line = true;
+ if (ch == curr_quote_2)
+ {
+ if (--quote_level == 0)
+ break;
+ }
+ else
+ quote_level += (ch == curr_quote_1);
+ p++;
+ n--;
+ }
+ while (n > 0);
+
+ count = p - readptr;
+ if (count > 0)
+ obstack_grow (obs_td, readptr, count);
+ count += (quote_level == 0);
+ assert (count > 0);
+ if (freadseek (isp->u.u_f.fp, count) < 0)
+ /* freadseek should not fail, since
+ count <= freadahead (isp->u.u_f.fp). */
+ abort ();
+ if (quote_level == 0)
+ break;
+ continue;
+ }
+ }
+ }
+ }
}
/* The general case. Proceed character by character. */
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