lnav/test/slicer.cc
2022-03-16 15:38:08 -07:00

100 lines
3.1 KiB
C++

/**
* Copyright (c) 2007-2012, 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.
*/
#include <string>
#include <vector>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "line_buffer.hh"
using namespace std;
int
main(int argc, char* argv[])
{
int retval = EXIT_SUCCESS;
vector<file_range> index;
auto_fd fd;
if (argc < 2) {
fprintf(stderr, "error: expecting file argument\n");
retval = EXIT_FAILURE;
} else if ((fd = open(argv[1], O_RDONLY)) == -1) {
perror("open");
retval = EXIT_FAILURE;
} else {
int line_number, start, end;
line_buffer lb;
file_range range;
lb.set_fd(fd);
while (true) {
auto load_result = lb.load_next_line(range);
if (load_result.isErr()) {
return EXIT_FAILURE;
}
auto li = load_result.unwrap();
if (li.li_file_range.empty()) {
break;
}
index.emplace_back(li.li_file_range);
range = li.li_file_range;
}
try {
while (scanf("%d:%d:%d", &line_number, &start, &end) == 3) {
range = index[line_number];
auto read_result = lb.read_range(range);
if (read_result.isErr()) {
return EXIT_FAILURE;
}
auto str = to_string(read_result.unwrap());
str = str.substr(start, end - start);
printf("%s\n", str.c_str());
}
} catch (line_buffer::error& e) {
fprintf(stderr, "error: line buffer %s\n", strerror(e.e_err));
}
}
return retval;
}