mirror of
https://github.com/tstack/lnav
synced 2024-11-09 19:10:52 +00:00
91 lines
2.8 KiB
C++
91 lines
2.8 KiB
C++
/**
|
|
* Copyright (c) 2014, Timothy Stack
|
|
*
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions are met:
|
|
*
|
|
* * Redistributions of source code must retain the above copyright notice, this
|
|
* list of conditions and the following disclaimer.
|
|
* * 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.
|
|
* * Neither the name of Timothy Stack 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 REGENTS 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 REGENTS 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.
|
|
*
|
|
* @file intern_string.cc
|
|
*/
|
|
|
|
#include "config.h"
|
|
|
|
#include <string.h>
|
|
|
|
#include "intern_string.hh"
|
|
|
|
const static int TABLE_SIZE = 4095;
|
|
static intern_string *TABLE[TABLE_SIZE];
|
|
|
|
unsigned long
|
|
hash_str(const char *str, size_t len)
|
|
{
|
|
unsigned long retval = 5381;
|
|
|
|
for (size_t lpc = 0; lpc < len; lpc++) {
|
|
/* retval * 33 + c */
|
|
retval = ((retval << 5) + retval) + (unsigned char)str[lpc];
|
|
}
|
|
|
|
return retval;
|
|
}
|
|
|
|
const intern_string *intern_string::lookup(const char *str, ssize_t len)
|
|
{
|
|
unsigned long h;
|
|
intern_string *curr;
|
|
|
|
if (len == -1) {
|
|
len = strlen(str);
|
|
}
|
|
h = hash_str(str, len) % TABLE_SIZE;
|
|
|
|
curr = TABLE[h];
|
|
while (curr != NULL) {
|
|
if (curr->is_len == len && strncmp(curr->is_str, str, len) == 0) {
|
|
return curr;
|
|
}
|
|
curr = curr->is_next;
|
|
}
|
|
|
|
char *strcp = new char[len + 1];
|
|
memcpy(strcp, str, len);
|
|
strcp[len] = '\0';
|
|
curr = new intern_string(strcp, len);
|
|
curr->is_next = TABLE[h];
|
|
TABLE[h] = curr;
|
|
|
|
return curr;
|
|
}
|
|
|
|
const intern_string *intern_string::lookup(const string_fragment &sf)
|
|
{
|
|
return lookup(sf.data(), sf.length());
|
|
}
|
|
|
|
const intern_string *intern_string::lookup(const std::string &str)
|
|
{
|
|
return lookup(str.c_str(), str.size());
|
|
}
|