mirror of
https://passt.top/passt
synced 2024-06-27 13:32:41 +00:00
ca2749e1bd
In practical terms, passt doesn't benefit from the additional protection offered by the AGPL over the GPL, because it's not suitable to be executed over a computer network. Further, restricting the distribution under the version 3 of the GPL wouldn't provide any practical advantage either, as long as the passt codebase is concerned, and might cause unnecessary compatibility dilemmas. Change licensing terms to the GNU General Public License Version 2, or any later version, with written permission from all current and past contributors, namely: myself, David Gibson, Laine Stump, Andrea Bolognani, Paul Holzinger, Richard W.M. Jones, Chris Kuhn, Florian Weimer, Giuseppe Scrivano, Stefan Hajnoczi, and Vasiliy Ulyanov. Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
116 lines
2.7 KiB
C
116 lines
2.7 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
|
|
/* PASST - Plug A Simple Socket Transport
|
|
* for qemu/UNIX domain socket mode
|
|
*
|
|
* PASTA - Pack A Subtle Tap Abstraction
|
|
* for network namespace/tap device mode
|
|
*
|
|
* lineread.c - Allocation free line-by-line buffered file input
|
|
*
|
|
* Copyright Red Hat
|
|
* Author: David Gibson <david@gibson.dropbear.id.au>
|
|
*/
|
|
|
|
#include <stddef.h>
|
|
#include <fcntl.h>
|
|
#include <string.h>
|
|
#include <stdbool.h>
|
|
#include <unistd.h>
|
|
|
|
#include "lineread.h"
|
|
#include "util.h"
|
|
|
|
/**
|
|
* lineread_init() - Prepare for line by line file reading without allocation
|
|
* @lr: Line reader state structure to initialize
|
|
* @fd: File descriptor to read lines from
|
|
*/
|
|
void lineread_init(struct lineread *lr, int fd)
|
|
{
|
|
lr->fd = fd;
|
|
lr->next_line = lr->count = 0;
|
|
}
|
|
|
|
/**
|
|
* peek_line() - Find and NULL-terminate next line in buffer
|
|
* @lr: Line reader state structure
|
|
* @eof: Caller indicates end-of-file was already found by read()
|
|
*
|
|
* Return: length of line in bytes, -1 if no line was found
|
|
*/
|
|
static int peek_line(struct lineread *lr, bool eof)
|
|
{
|
|
char *nl;
|
|
|
|
/* Sanity checks (which also document invariants) */
|
|
ASSERT(lr->count >= 0);
|
|
ASSERT(lr->next_line >= 0);
|
|
ASSERT(lr->next_line + lr->count >= lr->next_line);
|
|
ASSERT(lr->next_line + lr->count <= LINEREAD_BUFFER_SIZE);
|
|
|
|
nl = memchr(lr->buf + lr->next_line, '\n', lr->count);
|
|
|
|
if (nl) {
|
|
*nl = '\0';
|
|
return nl - lr->buf - lr->next_line + 1;
|
|
}
|
|
|
|
if (eof) {
|
|
lr->buf[lr->next_line + lr->count] = '\0';
|
|
/* No trailing newline, so treat all remaining bytes
|
|
* as the last line
|
|
*/
|
|
return lr->count;
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
/**
|
|
* lineread_get() - Read a single line from file (no allocation)
|
|
* @lr: Line reader state structure
|
|
* @line: Place a pointer to the next line in this variable
|
|
*
|
|
* Return: Length of line read on success, 0 on EOF, negative on error
|
|
*/
|
|
int lineread_get(struct lineread *lr, char **line)
|
|
{
|
|
bool eof = false;
|
|
int line_len;
|
|
|
|
while ((line_len = peek_line(lr, eof)) < 0) {
|
|
int rc;
|
|
|
|
if ((lr->next_line + lr->count) == LINEREAD_BUFFER_SIZE) {
|
|
/* No space at end */
|
|
if (lr->next_line == 0) {
|
|
/* Buffer is full, which means we've
|
|
* hit a line too long for us to
|
|
* process. FIXME: report error
|
|
* better
|
|
*/
|
|
return -1;
|
|
}
|
|
memmove(lr->buf, lr->buf + lr->next_line, lr->count);
|
|
lr->next_line = 0;
|
|
}
|
|
|
|
/* Read more data into the end of buffer */
|
|
rc = read(lr->fd, lr->buf + lr->next_line + lr->count,
|
|
LINEREAD_BUFFER_SIZE - lr->next_line - lr->count);
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
if (rc == 0)
|
|
eof = true;
|
|
else
|
|
lr->count += rc;
|
|
}
|
|
|
|
*line = lr->buf + lr->next_line;
|
|
lr->next_line += line_len;
|
|
lr->count -= line_len;
|
|
return line_len;
|
|
}
|