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980c9e198f
Currently, a linked list is used to keep track of all the Kconfig
files that have ever been parsed. Every time the "source" statement
is encountered, the linked list is traversed to check if the file has
been opened before. This prevents the same file from being recorded
in include/config/auto.conf.cmd again.
Given 1500+ Kconfig files parsed, a hashtable is now a more optimal
data structure.
By the way, you may wonder why we check this in the first place.
It matters only when the same file is included multiple times.
In old days, such a use case was forbidden, but commit f094f8a1b2
("kconfig: allow multiple inclusion of the same file") provided a bit
more flexibility. Of course, it is almost hypothetical...
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
154 lines
2.6 KiB
C
154 lines
2.6 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (C) 2002-2005 Roman Zippel <zippel@linux-m68k.org>
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* Copyright (C) 2002-2005 Sam Ravnborg <sam@ravnborg.org>
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*/
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#include <stdarg.h>
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#include <stdlib.h>
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#include <string.h>
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#include "hashtable.h"
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#include "lkc.h"
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unsigned int strhash(const char *s)
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{
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/* fnv32 hash */
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unsigned int hash = 2166136261U;
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for (; *s; s++)
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hash = (hash ^ *s) * 0x01000193;
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return hash;
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}
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/* hash table of all parsed Kconfig files */
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static HASHTABLE_DEFINE(file_hashtable, 1U << 11);
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struct file {
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struct hlist_node node;
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char name[];
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};
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/* file already present in list? If not add it */
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const char *file_lookup(const char *name)
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{
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struct file *file;
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size_t len;
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int hash = strhash(name);
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hash_for_each_possible(file_hashtable, file, node, hash)
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if (!strcmp(name, file->name))
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return file->name;
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len = strlen(name);
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file = xmalloc(sizeof(*file) + len + 1);
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memset(file, 0, sizeof(*file));
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memcpy(file->name, name, len);
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file->name[len] = '\0';
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hash_add(file_hashtable, &file->node, hash);
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str_printf(&autoconf_cmd, "\t%s \\\n", name);
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return file->name;
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}
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/* Allocate initial growable string */
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struct gstr str_new(void)
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{
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struct gstr gs;
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gs.s = xmalloc(sizeof(char) * 64);
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gs.len = 64;
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gs.max_width = 0;
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strcpy(gs.s, "\0");
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return gs;
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}
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/* Free storage for growable string */
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void str_free(struct gstr *gs)
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{
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free(gs->s);
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gs->s = NULL;
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gs->len = 0;
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}
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/* Append to growable string */
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void str_append(struct gstr *gs, const char *s)
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{
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size_t l;
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if (s) {
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l = strlen(gs->s) + strlen(s) + 1;
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if (l > gs->len) {
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gs->s = xrealloc(gs->s, l);
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gs->len = l;
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}
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strcat(gs->s, s);
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}
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}
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/* Append printf formatted string to growable string */
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void str_printf(struct gstr *gs, const char *fmt, ...)
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{
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va_list ap;
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char s[10000]; /* big enough... */
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va_start(ap, fmt);
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vsnprintf(s, sizeof(s), fmt, ap);
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str_append(gs, s);
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va_end(ap);
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}
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/* Retrieve value of growable string */
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char *str_get(struct gstr *gs)
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{
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return gs->s;
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}
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void *xmalloc(size_t size)
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{
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void *p = malloc(size);
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if (p)
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return p;
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fprintf(stderr, "Out of memory.\n");
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exit(1);
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}
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void *xcalloc(size_t nmemb, size_t size)
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{
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void *p = calloc(nmemb, size);
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if (p)
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return p;
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fprintf(stderr, "Out of memory.\n");
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exit(1);
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}
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void *xrealloc(void *p, size_t size)
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{
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p = realloc(p, size);
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if (p)
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return p;
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fprintf(stderr, "Out of memory.\n");
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exit(1);
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}
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char *xstrdup(const char *s)
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{
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char *p;
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p = strdup(s);
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if (p)
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return p;
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fprintf(stderr, "Out of memory.\n");
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exit(1);
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}
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char *xstrndup(const char *s, size_t n)
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{
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char *p;
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p = strndup(s, n);
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if (p)
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return p;
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fprintf(stderr, "Out of memory.\n");
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exit(1);
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}
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