Update copyright notice

[empserver] / src / client / secure.c

diff --git a/src/client/secure.c b/src/client/secure.c
index b691743565a20890d4f4b53fd8aede8fd0b64933..1a0650085f9df6641a4db6bc085a367b148fd54f 100644 (file)
--- a/src/client/secure.c
+++ b/src/client/secure.c
@@ -1,11 +1,11 @@
 /*
  *  Empire - A multi-player, client/server Internet based war game.
- *  Copyright (C) 1986-2008, Dave Pare, Jeff Bailey, Thomas Ruschak,
- *                           Ken Stevens, Steve McClure
+ *  Copyright (C) 1986-2020, Dave Pare, Jeff Bailey, Thomas Ruschak,
+ *                Ken Stevens, Steve McClure, Markus Armbruster
  *
- *  This program is free software; you can redistribute it and/or modify
+ *  Empire 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 of the License, or
+ *  the Free Software Foundation, either version 3 of the License, or
  *  (at your option) any later version.
  *
  *  This program is distributed in the hope that it will be useful,
@@ -14,8 +14,7 @@
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
- *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
  *  ---
  *
@@ -28,79 +27,81 @@
  *  secure.c: Check redir etc. to protect against tampering deity
  *
  *  Known contributors to this file:
- *     Markus Armbruster, 2007
+ *     Markus Armbruster, 2007-2017
  */
 
 #include <config.h>
 
 #include <assert.h>
+#include <ctype.h>
+#include <stdio.h>
 #include <string.h>
 #include "ringbuf.h"
 #include "secure.h"
 
 static struct ring recent_input;
-static size_t saved_bytes;
 
 /*
- * Remember line of input INP for a while.
- * It must end with a newline.
- * Return value is suitable for forget_input(): it makes it forget all
- * input up to and including this line.
+ * Remember input @inp for a while.
  */
-size_t
-save_input(char *inp)
+void
+save_input(char inp)
 {
-    size_t len = strlen(inp);
     int eol;
 
-    assert(len && inp[len - 1] == '\n');
-
-    while (ring_putm(&recent_input, inp, len) < 0) {
-       eol = ring_search(&recent_input, "\n");
+    while (ring_putc(&recent_input, inp) < 0) {
+       eol = ring_search(&recent_input, "\n", 0);
        assert(eol >= 0);
        ring_discard(&recent_input, eol + 1);
     }
-    saved_bytes += len;
-    return saved_bytes;
 }
 
 /*
- * Can you still remember a line of input that ends with TAIL?
+ * Can you still remember a line of input that ends with @tail?
  * It must end with a newline.
- * Return non-zero iff TAIL can be remembered.
- * Passing that value to forget_input() will forget all input up to
- * and including this line.
  */
-size_t
+int
 seen_input(char *tail)
 {
     size_t len = strlen(tail);
-    size_t remembered = ring_len(&recent_input);
-    int dist;
 
     assert(len && tail[len - 1] == '\n');
-
-    dist = ring_search(&recent_input, tail);
-    if (dist < 0)
-       return 0;
-
-    assert(dist + len <= remembered && remembered <= saved_bytes);
-    return saved_bytes - remembered + dist + len;
+    return ring_search(&recent_input, tail, 0) >= 0;
 }
 
 /*
- * Forget remembered input up to SEEN.
- * SEEN should be obtained from save_input() or seen_input().
+ * Can you still remember input that looks like an execute @arg?
+ * @arg must end with a newline.
  */
-void
-forget_input(size_t seen)
+int
+seen_exec_input(char *arg)
 {
-    size_t forgotten = saved_bytes - ring_len(&recent_input);
+    size_t len = strlen(arg);
+    int n, i, j, ch;
+    unsigned char buf[RING_SIZE + 1];
+
+    assert(len && arg[len - 1] == '\n');
+
+    n = 1;
+    for (;;) {
+       /* find next line ending with arg */
+       n = ring_search(&recent_input, arg, n + 1);
+       if (n <= 0)
+           return 0;
 
-    assert(seen);
+       /* extract command (same or previous line) */
+       i = n - 1;
+       if (ring_peek(&recent_input, i) == '\n')
+           i--;
+       j = sizeof(buf);
+       buf[--j] = 0;
+       for (; i >= 0 && (ch = ring_peek(&recent_input, i)) != '\n'; i--)
+           buf[--j] = ch;
 
-    if (seen > forgotten) {
-       assert(ring_peek(&recent_input, seen - forgotten - 1) == '\n');
-       ring_discard(&recent_input, seen - forgotten);
+       /* compare command */
+       for (; isspace(buf[j]); j++) ;
+       for (i = j; buf[i] && !isspace(buf[i]); i++) ;
+       if (i - j >= 2 && !strncmp("execute", (char *)buf + j, i - j))
+           return 1;
     }
 }