1 /*
2 * The PCI Library -- ID to Name Hash
3 *
4 * Copyright (c) 1997--2008 Martin Mares <[email protected]>
5 *
6 * Can be freely distributed and used under the terms of the GNU GPL v2+.
7 *
8 * SPDX-License-Identifier: GPL-2.0-or-later
9 */
10
11 #include <string.h>
12
13 #include "internal.h"
14 #include "names.h"
15
16 struct id_bucket {
17 struct id_bucket *next;
18 unsigned int full;
19 };
20
21 #ifdef __GNUC__
22 #define BUCKET_ALIGNMENT __alignof__(struct id_bucket)
23 #else
24 union id_align {
25 struct id_bucket *next;
26 unsigned int full;
27 };
28 #define BUCKET_ALIGNMENT sizeof(union id_align)
29 #endif
30 #define BUCKET_ALIGN(n) ((n)+BUCKET_ALIGNMENT-(n)%BUCKET_ALIGNMENT)
31
id_alloc(struct pci_access * a,unsigned int size)32 static void *id_alloc(struct pci_access *a, unsigned int size)
33 {
34 struct id_bucket *buck = a->current_id_bucket;
35 unsigned int pos;
36
37 if (!a->id_hash)
38 {
39 a->id_hash = pci_malloc(a, sizeof(struct id_entry *) * HASH_SIZE);
40 memset(a->id_hash, 0, sizeof(struct id_entry *) * HASH_SIZE);
41 }
42
43 if (!buck || buck->full + size > BUCKET_SIZE)
44 {
45 buck = pci_malloc(a, BUCKET_SIZE);
46 buck->next = a->current_id_bucket;
47 a->current_id_bucket = buck;
48 buck->full = BUCKET_ALIGN(sizeof(struct id_bucket));
49 }
50 pos = buck->full;
51 buck->full = BUCKET_ALIGN(buck->full + size);
52 return (byte *)buck + pos;
53 }
54
id_hash(int cat,u32 id12,u32 id34)55 static inline unsigned int id_hash(int cat, u32 id12, u32 id34)
56 {
57 unsigned int h;
58
59 h = id12 ^ (id34 << 3) ^ (cat << 5);
60 return h % HASH_SIZE;
61 }
62
63 int
pci_id_insert(struct pci_access * a,int cat,int id1,int id2,int id3,int id4,char * text,enum id_entry_src src)64 pci_id_insert(struct pci_access *a, int cat, int id1, int id2, int id3, int id4, char *text, enum id_entry_src src)
65 {
66 u32 id12 = id_pair(id1, id2);
67 u32 id34 = id_pair(id3, id4);
68 unsigned int h = id_hash(cat, id12, id34);
69 struct id_entry *n = a->id_hash ? a->id_hash[h] : NULL;
70 int len = strlen(text);
71
72 while (n && (n->id12 != id12 || n->id34 != id34 || n->cat != cat))
73 n = n->next;
74 if (n)
75 return 1;
76 n = id_alloc(a, sizeof(struct id_entry) + len);
77 n->id12 = id12;
78 n->id34 = id34;
79 n->cat = cat;
80 n->src = src;
81 memcpy(n->name, text, len+1);
82 n->next = a->id_hash[h];
83 a->id_hash[h] = n;
84 return 0;
85 }
86
87 char
pci_id_lookup(struct pci_access * a,int flags,int cat,int id1,int id2,int id3,int id4)88 *pci_id_lookup(struct pci_access *a, int flags, int cat, int id1, int id2, int id3, int id4)
89 {
90 struct id_entry *n, *best;
91 u32 id12 = id_pair(id1, id2);
92 u32 id34 = id_pair(id3, id4);
93
94 if (a->id_hash)
95 {
96 n = a->id_hash[id_hash(cat, id12, id34)];
97 best = NULL;
98 for (; n; n=n->next)
99 {
100 if (n->id12 != id12 || n->id34 != id34 || n->cat != cat)
101 continue;
102 if (n->src == SRC_LOCAL && (flags & PCI_LOOKUP_SKIP_LOCAL))
103 continue;
104 if (n->src == SRC_NET && !(flags & PCI_LOOKUP_NETWORK))
105 continue;
106 if (n->src == SRC_CACHE && !(flags & PCI_LOOKUP_CACHE))
107 continue;
108 if (n->src == SRC_HWDB && (flags & (PCI_LOOKUP_SKIP_LOCAL | PCI_LOOKUP_NO_HWDB)))
109 continue;
110 if (!best || best->src < n->src)
111 best = n;
112 }
113 if (best)
114 return best->name;
115 }
116 return NULL;
117 }
118
119 void
pci_id_hash_free(struct pci_access * a)120 pci_id_hash_free(struct pci_access *a)
121 {
122 pci_mfree(a->id_hash);
123 a->id_hash = NULL;
124 while (a->current_id_bucket)
125 {
126 struct id_bucket *buck = a->current_id_bucket;
127 a->current_id_bucket = buck->next;
128 pci_mfree(buck);
129 }
130 }
131