1 /**********************************************************************
2 Freeciv - Copyright (C) 1996 - A Kjeldberg, L Gregersen, P Unold
3 This program is free software; you can redistribute it and/or modify
4 it under the terms of the GNU General Public License as published by
5 the Free Software Foundation; either version 2, or (at your option)
6 any later version.
7
8 This program is distributed in the hope that it will be useful,
9 but WITHOUT ANY WARRANTY; without even the implied warranty of
10 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 GNU General Public License for more details.
12 ***********************************************************************/
13
14 #ifdef HAVE_CONFIG_H
15 #include <fc_config.h>
16 #endif
17
18 #include "fc_prehdrs.h"
19
20 #include <string.h>
21
22 /* utility */
23 #include "shared.h" /* TRUE, FALSE */
24 #include "support.h" /* fc_is* */
25
26 #include "capability.h"
27
28 #define GET_TOKEN(start, end) \
29 { \
30 /* skip leading whitespace */ \
31 while (fc_isspace(*start)) { \
32 start++; \
33 } \
34 /* skip to end of token */ \
35 for (end = start; *end != '\0' && !fc_isspace(*end) && *end != ','; \
36 end++) { \
37 /* nothing */ \
38 } \
39 }
40
41 /***************************************************************************
42 This routine returns true if the capability in cap appears
43 in the capability list in capstr. The capabilities in capstr
44 are allowed to start with a "+", but the capability in cap must not.
45 ***************************************************************************/
fc_has_capability(const char * cap,const char * capstr,const size_t cap_len)46 static bool fc_has_capability(const char *cap, const char *capstr,
47 const size_t cap_len)
48 {
49 const char *next;
50
51 fc_assert_ret_val(capstr != NULL, FALSE);
52
53 for (;;) {
54 GET_TOKEN(capstr, next);
55
56 if (*capstr == '+') {
57 capstr++;
58 }
59
60 fc_assert(next >= capstr);
61
62 if (((size_t)(next - capstr) == cap_len)
63 && strncmp(cap, capstr, cap_len) == 0) {
64 return TRUE;
65 }
66 if (*next == '\0') {
67 return FALSE;
68 }
69
70 capstr = next + 1;
71 }
72 }
73
74 /***************************************************************************
75 Wrapper for fc_has_capability() for NULL terminated strings.
76 ***************************************************************************/
has_capability(const char * cap,const char * capstr)77 bool has_capability(const char *cap, const char *capstr)
78 {
79 return fc_has_capability(cap, capstr, strlen(cap));
80 }
81
82 /***************************************************************************
83 This routine returns true if all the mandatory capabilities in
84 us appear in them.
85 ***************************************************************************/
has_capabilities(const char * us,const char * them)86 bool has_capabilities(const char *us, const char *them)
87 {
88 const char *next;
89
90 for (;;) {
91 GET_TOKEN(us, next);
92
93 if (*us == '+' && !fc_has_capability(us+1, them, next-(us+1))) {
94 return FALSE;
95 }
96 if (*next == '\0') {
97 return TRUE;
98 }
99
100 us = next+1;
101 }
102 }
103