xref: /linux/scripts/kconfig/util.c (revision a9d83d74783b00f9189c14180f77bbed133b092c)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2002-2005 Roman Zippel <zippel@linux-m68k.org>
4  * Copyright (C) 2002-2005 Sam Ravnborg <sam@ravnborg.org>
5  */
6 
7 #include <stdarg.h>
8 #include <stdlib.h>
9 #include <string.h>
10 
11 #include <hashtable.h>
12 #include <xalloc.h>
13 #include "lkc.h"
14 
15 unsigned int strhash(const char *s)
16 {
17 	/* fnv32 hash */
18 	unsigned int hash = 2166136261U;
19 
20 	for (; *s; s++)
21 		hash = (hash ^ *s) * 0x01000193;
22 	return hash;
23 }
24 
25 /* hash table of all parsed Kconfig files */
26 static HASHTABLE_DEFINE(file_hashtable, 1U << 11);
27 
28 struct file {
29 	struct hlist_node node;
30 	char name[];
31 };
32 
33 /* file already present in list? If not add it */
34 const char *file_lookup(const char *name)
35 {
36 	struct file *file;
37 	size_t len;
38 	int hash = strhash(name);
39 
40 	hash_for_each_possible(file_hashtable, file, node, hash)
41 		if (!strcmp(name, file->name))
42 			return file->name;
43 
44 	len = strlen(name);
45 	file = xmalloc(sizeof(*file) + len + 1);
46 	memset(file, 0, sizeof(*file));
47 	memcpy(file->name, name, len);
48 	file->name[len] = '\0';
49 
50 	hash_add(file_hashtable, &file->node, hash);
51 
52 	str_printf(&autoconf_cmd, "\t%s \\\n", name);
53 
54 	return file->name;
55 }
56 
57 /* Allocate initial growable string */
58 struct gstr str_new(void)
59 {
60 	struct gstr gs;
61 	gs.s = xmalloc(sizeof(char) * 64);
62 	gs.len = 64;
63 	gs.max_width = 0;
64 	strcpy(gs.s, "\0");
65 	return gs;
66 }
67 
68 /* Free storage for growable string */
69 void str_free(struct gstr *gs)
70 {
71 	free(gs->s);
72 	gs->s = NULL;
73 	gs->len = 0;
74 }
75 
76 /* Append to growable string */
77 void str_append(struct gstr *gs, const char *s)
78 {
79 	size_t l;
80 	if (s) {
81 		l = strlen(gs->s) + strlen(s) + 1;
82 		if (l > gs->len) {
83 			gs->s = xrealloc(gs->s, l);
84 			gs->len = l;
85 		}
86 		strcat(gs->s, s);
87 	}
88 }
89 
90 /* Append printf formatted string to growable string */
91 void str_printf(struct gstr *gs, const char *fmt, ...)
92 {
93 	va_list ap;
94 	char s[10000]; /* big enough... */
95 	va_start(ap, fmt);
96 	vsnprintf(s, sizeof(s), fmt, ap);
97 	str_append(gs, s);
98 	va_end(ap);
99 }
100 
101 /* Retrieve value of growable string */
102 char *str_get(const struct gstr *gs)
103 {
104 	return gs->s;
105 }
106