134 lines
3.5 KiB
C
134 lines
3.5 KiB
C
/* Implement the SELECT statement for character variables.
|
|
Copyright (C) 2008-2019 Free Software Foundation, Inc.
|
|
|
|
This file is part of the GNU Fortran runtime library (libgfortran).
|
|
|
|
Libgfortran 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 3, or (at your option)
|
|
any later version.
|
|
|
|
Libgfortran is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
Under Section 7 of GPL version 3, you are granted additional
|
|
permissions described in the GCC Runtime Library Exception, version
|
|
3.1, as published by the Free Software Foundation.
|
|
|
|
You should have received a copy of the GNU General Public License and
|
|
a copy of the GCC Runtime Library Exception along with this program;
|
|
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#define select_string SUFFIX(select_string)
|
|
#define select_struct SUFFIX(select_struct)
|
|
#define compare_string SUFFIX(compare_string)
|
|
|
|
typedef struct
|
|
{
|
|
CHARTYPE *low;
|
|
gfc_charlen_type low_len;
|
|
CHARTYPE *high;
|
|
gfc_charlen_type high_len;
|
|
int address;
|
|
}
|
|
select_struct;
|
|
|
|
extern int select_string (select_struct *table, int table_len,
|
|
const CHARTYPE *selector,
|
|
gfc_charlen_type selector_len);
|
|
export_proto(select_string);
|
|
|
|
|
|
/* select_string()-- Given a selector string and a table of
|
|
* select_struct structures, return the address to jump to. */
|
|
|
|
int
|
|
select_string (select_struct *table, int table_len, const CHARTYPE *selector,
|
|
gfc_charlen_type selector_len)
|
|
{
|
|
select_struct *t;
|
|
int i, low, high, mid;
|
|
int default_jump = -1;
|
|
|
|
if (table_len == 0)
|
|
return -1;
|
|
|
|
/* Record the default address if present */
|
|
|
|
if (table->low == NULL && table->high == NULL)
|
|
{
|
|
default_jump = table->address;
|
|
|
|
table++;
|
|
table_len--;
|
|
if (table_len == 0)
|
|
return default_jump;
|
|
}
|
|
|
|
/* Try the high and low bounds if present. */
|
|
|
|
if (table->low == NULL)
|
|
{
|
|
if (compare_string (table->high_len, table->high,
|
|
selector_len, selector) >= 0)
|
|
return table->address;
|
|
|
|
table++;
|
|
table_len--;
|
|
if (table_len == 0)
|
|
return default_jump;
|
|
}
|
|
|
|
t = table + table_len - 1;
|
|
|
|
if (t->high == NULL)
|
|
{
|
|
if (compare_string (t->low_len, t->low, selector_len, selector) <= 0)
|
|
return t->address;
|
|
|
|
table_len--;
|
|
if (table_len == 0)
|
|
return default_jump;
|
|
}
|
|
|
|
/* At this point, the only table entries are bounded entries. Find
|
|
the right entry with a binary chop. */
|
|
|
|
low = -1;
|
|
high = table_len;
|
|
|
|
while (low + 1 < high)
|
|
{
|
|
mid = (low + high) / 2;
|
|
|
|
t = table + mid;
|
|
i = compare_string (t->low_len, t->low, selector_len, selector);
|
|
|
|
if (i == 0)
|
|
return t->address;
|
|
|
|
if (i < 0)
|
|
low = mid;
|
|
else
|
|
high = mid;
|
|
}
|
|
|
|
/* The string now lies between the low indeces of the now-adjacent
|
|
high and low entries. Because it is less than the low entry of
|
|
'high', it can't be that one. If low is still -1, then no
|
|
entries match. Otherwise, we have to check the high entry of
|
|
'low'. */
|
|
|
|
if (low == -1)
|
|
return default_jump;
|
|
|
|
t = table + low;
|
|
if (compare_string (selector_len, selector, t->high_len, t->high) <= 0)
|
|
return t->address;
|
|
|
|
return default_jump;
|
|
}
|