osd-contiki/core/loader/symtab.c

84 lines
2.8 KiB
C

/*
* Copyright (c) 2005, Swedish Institute of Computer Science
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is part of the Contiki operating system.
*
* @(#)$Id: symtab.c,v 1.7 2007/01/24 16:13:50 adamdunkels Exp $
*/
#include "symtab.h"
#include "loader/symbols.h"
#include <string.h>
/* Binary search is twice as large but still small. */
#ifndef SYMTAB_CONF_BINARY_SEARCH
#define SYMTAB_CONF_BINARY_SEARCH 1
#endif
/*---------------------------------------------------------------------------*/
#if SYMTAB_CONF_BINARY_SEARCH
void *
symtab_lookup(const char *name)
{
int start, middle, end;
int r;
start = 0;
end = symbols_nelts - 1; /* Last entry is { 0, 0 }. */
while(start <= end) {
/* Check middle, divide */
middle = (start + end) / 2;
r = strcmp(name, symbols[middle].name);
if(r < 0) {
end = middle - 1;
} else if(r > 0) {
start = middle + 1;
} else {
return symbols[middle].value;
}
}
return NULL;
}
#else /* SYMTAB_CONF_BINARY_SEARCH */
void *
symtab_lookup(const char *name)
{
const struct symbols *s;
for(s = symbols; s->name != NULL; ++s) {
if(strcmp(name, s->name) == 0) {
return s->value;
}
}
return 0;
}
#endif /* SYMTAB_CONF_BINARY_SEARCH */
/*---------------------------------------------------------------------------*/