ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/deliantra/server/include/shstr.h
(Generate patch)

Comparing deliantra/server/include/shstr.h (file contents):
Revision 1.4 by root, Thu Aug 31 17:54:14 2006 UTC vs.
Revision 1.7 by root, Sun Sep 3 09:00:09 2006 UTC

1#ifndef SHSTR_H__ 1#ifndef SHSTR_H__
2#define SHSTR_H__ 2#define SHSTR_H__
3 3
4//// OLD STUFF
5
6/* The size of the shared strings hashtable. This must be smaller than
7 * 32767, but 947 ought to be plenty enough.
8 */
9#define TABLESIZE 4133
10
11/* This specifies how many characters the hashing routine should look at.
12 * You may actually save CPU by increasing this number if the typical string
13 * is large.
14 */
15#ifndef MAXSTRING
16#define MAXSTRING 20
17#endif
18
19/* In the unlikely occurence that 16383 references to a string are too
20 * few, you can modify the below type to something bigger.
21 * (The top bit of "refcount" is used to signify that "u.array" points
22 * at the array entry.)
23 */
24#define REFCOUNT_TYPE int
25
26/* The offsetof macro is part of ANSI C, but many compilers lack it, for
27 * example "gcc -ansi"
28 */
29#if !defined (offsetof)
30#define offsetof(type, member) (int)&(((type *)0)->member)
31#endif
32
33/* SS(string) will return the address of the shared_string struct which
34 * contains "string".
35 */
36#define SS(x) ((shared_string *) ((x) - offsetof(shared_string, string)))
37
38#define SS_STATISTICS
39
40#define SS_DUMP_TABLE 1
41#define SS_DUMP_TOTALS 2
42
43#ifdef SS_STATISTICS
44static struct statistics {
45 int calls;
46 int hashed;
47 int strcmps;
48 int search;
49 int linked;
50} add_stats, add_ref_stats, free_stats, find_stats, hash_stats;
51#define GATHER(n) (++n)
52#else /* !SS_STATISTICS */
53#define GATHER(n)
54#endif /* SS_STATISTICS */
55
56#define TOPBIT ((unsigned REFCOUNT_TYPE) 1 << (sizeof(REFCOUNT_TYPE) * CHAR_BIT - 1))
57
58#define PADDING ((2 * sizeof(long) - sizeof(REFCOUNT_TYPE)) % sizeof(long)) + 1
59
60typedef struct _shared_string {
61 union {
62 struct _shared_string **array;
63 struct _shared_string *previous;
64 } u;
65 struct _shared_string *next;
66 /* The top bit of "refcount" is used to signify that "u.array" points
67 * at the array entry.
68 */
69 unsigned REFCOUNT_TYPE refcount;
70 /* Padding will be unused memory, since we can't know how large
71 * the padding when allocating memory. We assume here that
72 * sizeof(long) is a good boundary.
73 */
74 char string[PADDING];
75} shared_string;
76
77extern void init_hash_table(void);
78extern const char *add_string(const char *str);
79extern const char *add_refcount(const char *str);
80extern int query_refcount(const char *str);
81extern const char *find_string(const char *str);
82extern void free_string(const char *str);
83extern void ss_dump_statistics(void);
84extern const char *ss_dump_table(int what);
85extern int buf_overflow(const char *buf1, const char *buf2, int bufsize); 4extern int buf_overflow(const char *buf1, const char *buf2, int bufsize);
86 5
87//// NEW STUFF
88
89#if 0
90struct shstr 6struct shstr
91{ 7{
92 const char *s; 8 const char *s;
9
10 static int &refcnt (const char *s)
11 {
12 return *((int *)s - 1);
13 }
14
15 static int &length (const char *s)
16 {
17 return *((int *)s - 2);
18 }
19
20 int &refcnt () const
21 {
22 return refcnt (s);
23 }
24
25 int length () const
26 {
27 return s ? length (s) : 0;
28 }
29
30 static const char *find (const char *s);
31 static const char *intern (const char *s);
32
33 static void gc (); // garbage collect a few strings
34
35 // this is used for informational messages and the like
36 const char *operator &() const { return s ? s : "<nil>"; }
37
38 const char &operator [](int i) const { return s[i]; }
93 operator const char *() const { return s; }; 39 operator const char *() const { return s; }
40
41 shstr ()
42 : s (0)
43 {
44 }
45
46 shstr (const shstr &sh)
47 : s (sh.s)
48 {
49 if (s) ++refcnt ();
50 }
51
52 explicit shstr (const char *s)
53 : s (intern (s))
54 {
55 }
56
57 ~shstr ()
58 {
59 if (s) --refcnt ();
60 }
61
62 const shstr &operator =(const shstr &sh)
63 {
64 if (s) --refcnt ();
65 s = sh.s;
66 if (s) ++refcnt ();
67
68 return *this;
69 }
70
94 shstr &operator =(const char *str) { s = str; }; 71 const shstr &operator =(const char *str)
72 {
73 if (s) --refcnt ();
74 s = intern (str);
75
76 return *this;
77 }
95}; 78};
96#else 79
97typedef const char *shstr; 80inline int strlen (const shstr &sh)
98#endif 81{
82 return sh.length ();
83}
84
85inline bool operator ==(const shstr &a, const shstr &b)
86{
87 return a.s == b.s;
88}
89
90inline bool operator !=(const shstr &a, const shstr &b)
91{
92 return !(a == b);
93}
99 94
100#endif 95#endif
101 96

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines