opnsense-src/lib/libc/tests/stdio/getdelim_test.c
Bryan Drewery 8f8a794775 getdelim(3): Fix losing data on [EAGAIN]
Currently when an [EAGAIN] is encountered we return a partial result
that does not contain the delimeter.  On the next (successful) read we
were returning the next part of the line without the preceding string
from the first failed call.

Fix this by using the same mechanism as ungetc(3) does.  For the buffered
case we could simply set fp->_r and fp->_p back to their values before
sappend() is ran but for simplicity ungetc(3) is done in there as well.

Reviewed by:	kib
Differential Revision: https://reviews.freebsd.org/D31687
2021-09-02 11:26:26 -07:00

434 lines
11 KiB
C

/*-
* Copyright (c) 2009 David Schultz <das@FreeBSD.org>
* Copyright (c) 2021 Dell EMC
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <atf-c.h>
#define CHUNK_MAX 10
/* The assertions depend on this string. */
char apothegm[] = "All work and no play\0 makes Jack a dull boy.\n";
/*
* This is a neurotic reader function designed to give getdelim() a
* hard time. It reads through the string `apothegm' and returns a
* random number of bytes up to the requested length.
*/
static int
_reader(void *cookie, char *buf, int len)
{
size_t *offp = cookie;
size_t r;
r = random() % CHUNK_MAX + 1;
if (len > r)
len = r;
if (len > sizeof(apothegm) - *offp)
len = sizeof(apothegm) - *offp;
memcpy(buf, apothegm + *offp, len);
*offp += len;
return (len);
}
static FILE *
mkfilebuf(void)
{
size_t *offp;
offp = malloc(sizeof(*offp)); /* XXX leak */
*offp = 0;
return (fropen(offp, _reader));
}
ATF_TC_WITHOUT_HEAD(getline_basic);
ATF_TC_BODY(getline_basic, tc)
{
FILE *fp;
char *line;
size_t linecap;
int i;
srandom(0);
/*
* Test multiple times with different buffer sizes
* and different _reader() return values.
*/
errno = 0;
for (i = 0; i < 8; i++) {
fp = mkfilebuf();
linecap = i;
line = malloc(i);
/* First line: the full apothegm */
ATF_REQUIRE(getline(&line, &linecap, fp) == sizeof(apothegm) - 1);
ATF_REQUIRE(memcmp(line, apothegm, sizeof(apothegm)) == 0);
ATF_REQUIRE(linecap >= sizeof(apothegm));
/* Second line: the NUL terminator following the newline */
ATF_REQUIRE(getline(&line, &linecap, fp) == 1);
ATF_REQUIRE(line[0] == '\0' && line[1] == '\0');
/* Third line: EOF */
line[0] = 'X';
ATF_REQUIRE(getline(&line, &linecap, fp) == -1);
ATF_REQUIRE(line[0] == '\0');
free(line);
line = NULL;
ATF_REQUIRE(feof(fp));
ATF_REQUIRE(!ferror(fp));
fclose(fp);
}
ATF_REQUIRE(errno == 0);
}
ATF_TC_WITHOUT_HEAD(stream_error);
ATF_TC_BODY(stream_error, tc)
{
char *line;
size_t linecap;
/* Make sure read errors are handled properly. */
line = NULL;
linecap = 0;
errno = 0;
ATF_REQUIRE(getline(&line, &linecap, stdout) == -1);
ATF_REQUIRE(errno == EBADF);
errno = 0;
ATF_REQUIRE(getdelim(&line, &linecap, 'X', stdout) == -1);
ATF_REQUIRE(errno == EBADF);
ATF_REQUIRE(ferror(stdout));
}
ATF_TC_WITHOUT_HEAD(invalid_params);
ATF_TC_BODY(invalid_params, tc)
{
FILE *fp;
char *line;
size_t linecap;
/* Make sure NULL linep or linecapp pointers are handled. */
fp = mkfilebuf();
ATF_REQUIRE(getline(NULL, &linecap, fp) == -1);
ATF_REQUIRE(errno == EINVAL);
ATF_REQUIRE(getline(&line, NULL, fp) == -1);
ATF_REQUIRE(errno == EINVAL);
ATF_REQUIRE(ferror(fp));
fclose(fp);
}
ATF_TC_WITHOUT_HEAD(eof);
ATF_TC_BODY(eof, tc)
{
FILE *fp;
char *line;
size_t linecap;
/* Make sure getline() allocates memory as needed if fp is at EOF. */
errno = 0;
fp = mkfilebuf();
while (!feof(fp)) /* advance to EOF; can't fseek this stream */
getc(fp);
line = NULL;
linecap = 0;
printf("getline\n");
ATF_REQUIRE(getline(&line, &linecap, fp) == -1);
ATF_REQUIRE(line[0] == '\0');
ATF_REQUIRE(linecap > 0);
ATF_REQUIRE(errno == 0);
printf("feof\n");
ATF_REQUIRE(feof(fp));
ATF_REQUIRE(!ferror(fp));
fclose(fp);
}
ATF_TC_WITHOUT_HEAD(nul);
ATF_TC_BODY(nul, tc)
{
FILE *fp;
char *line;
size_t linecap, n;
errno = 0;
line = NULL;
linecap = 0;
/* Make sure a NUL delimiter works. */
fp = mkfilebuf();
n = strlen(apothegm);
printf("getdelim\n");
ATF_REQUIRE(getdelim(&line, &linecap, '\0', fp) == n + 1);
ATF_REQUIRE(strcmp(line, apothegm) == 0);
ATF_REQUIRE(line[n + 1] == '\0');
ATF_REQUIRE(linecap > n + 1);
n = strlen(apothegm + n + 1);
printf("getdelim 2\n");
ATF_REQUIRE(getdelim(&line, &linecap, '\0', fp) == n + 1);
ATF_REQUIRE(line[n + 1] == '\0');
ATF_REQUIRE(linecap > n + 1);
ATF_REQUIRE(errno == 0);
ATF_REQUIRE(!ferror(fp));
fclose(fp);
}
ATF_TC_WITHOUT_HEAD(empty_NULL_buffer);
ATF_TC_BODY(empty_NULL_buffer, tc)
{
FILE *fp;
char *line;
size_t linecap;
/* Make sure NULL *linep and zero *linecapp are handled. */
fp = mkfilebuf();
line = NULL;
linecap = 42;
ATF_REQUIRE(getline(&line, &linecap, fp) == sizeof(apothegm) - 1);
ATF_REQUIRE(memcmp(line, apothegm, sizeof(apothegm)) == 0);
fp = mkfilebuf();
free(line);
line = malloc(100);
linecap = 0;
ATF_REQUIRE(getline(&line, &linecap, fp) == sizeof(apothegm) - 1);
ATF_REQUIRE(memcmp(line, apothegm, sizeof(apothegm)) == 0);
free(line);
ATF_REQUIRE(!ferror(fp));
fclose(fp);
}
static void
_ipc_read(int fd, char wait_c)
{
char c;
ssize_t len;
c = 0;
while (c != wait_c) {
len = read(fd, &c, 1);
ATF_CHECK_MSG(len != 0,
"EOF on IPC pipe while waiting. Did other side fail?");
ATF_CHECK_MSG(len == 1 || errno == EINTR,
"read %zu bytes errno %d\n", len, errno);
if (len != 1 || errno != EINTR)
break;
}
}
static void
_ipc_write(int fd, char c)
{
while ((write(fd, &c, 1) != 1))
ATF_REQUIRE(errno == EINTR);
}
static void
ipc_wait(int ipcfd[2])
{
_ipc_read(ipcfd[0], '+');
/* Send ACK. */
_ipc_write(ipcfd[1], '-');
}
static void
ipc_wakeup(int ipcfd[2])
{
_ipc_write(ipcfd[1], '+');
/* Wait for ACK. */
_ipc_read(ipcfd[0], '-');
}
static void
_nonblock_eagain(int buf_mode)
{
FILE *fp;
const char delim = '!';
const char *strs[] = {
"first line partial!",
"second line is sent in full!",
"third line is sent partially!",
"last line is sent in full!",
};
char *line;
size_t linecap, strslen[nitems(strs)];
ssize_t linelen;
int fd_fifo, flags, i, ipcfd[2], pipedes[2], pipedes2[2], status;
pid_t pid;
line = NULL;
linecap = 0;
for (i = 0; i < nitems(strslen); i++)
strslen[i] = strlen(strs[i]);
ATF_REQUIRE(pipe2(pipedes, O_CLOEXEC) == 0);
ATF_REQUIRE(pipe2(pipedes2, O_CLOEXEC) == 0);
(void)unlink("fifo");
ATF_REQUIRE(mkfifo("fifo", 0666) == 0);
ATF_REQUIRE((pid = fork()) >= 0);
if (pid == 0) {
close(pipedes[0]);
ipcfd[1] = pipedes[1];
ipcfd[0] = pipedes2[0];
close(pipedes2[1]);
ATF_REQUIRE((fd_fifo = open("fifo", O_WRONLY)) != -1);
/* Partial write. */
ATF_REQUIRE(write(fd_fifo, strs[0], strslen[0] - 3) ==
strslen[0] - 3);
ipc_wakeup(ipcfd);
ipc_wait(ipcfd);
/* Finish off the first line. */
ATF_REQUIRE(write(fd_fifo,
&(strs[0][strslen[0] - 3]), 3) == 3);
/* And include the second full line and a partial 3rd line. */
ATF_REQUIRE(write(fd_fifo, strs[1], strslen[1]) == strslen[1]);
ATF_REQUIRE(write(fd_fifo, strs[2], strslen[2] - 3) ==
strslen[2] - 3);
ipc_wakeup(ipcfd);
ipc_wait(ipcfd);
/* Finish the partial write and partially send the last. */
ATF_REQUIRE(write(fd_fifo,
&(strs[2][strslen[2] - 3]), 3) == 3);
ATF_REQUIRE(write(fd_fifo, strs[3], strslen[3] - 3) ==
strslen[3] - 3);
ipc_wakeup(ipcfd);
ipc_wait(ipcfd);
/* Finish the write */
ATF_REQUIRE(write(fd_fifo,
&(strs[3][strslen[3] - 3]), 3) == 3);
ipc_wakeup(ipcfd);
_exit(0);
}
ipcfd[0] = pipedes[0];
close(pipedes[1]);
close(pipedes2[0]);
ipcfd[1] = pipedes2[1];
ATF_REQUIRE((fp = fopen("fifo", "r")) != NULL);
setvbuf(fp, (char *)NULL, buf_mode, 0);
ATF_REQUIRE((flags = fcntl(fileno(fp), F_GETFL, 0)) != -1);
ATF_REQUIRE(fcntl(fileno(fp), F_SETFL, flags | O_NONBLOCK) >= 0);
/* Wait until the writer completes its partial write. */
ipc_wait(ipcfd);
ATF_REQUIRE_ERRNO(EAGAIN,
(linelen = getdelim(&line, &linecap, delim, fp)) == -1);
ATF_REQUIRE_STREQ("", line);
ATF_REQUIRE(ferror(fp));
ATF_REQUIRE(!feof(fp));
clearerr(fp);
ipc_wakeup(ipcfd);
ipc_wait(ipcfd);
/*
* Should now have the finished first line, a full second line,
* and a partial third line.
*/
ATF_CHECK(getdelim(&line, &linecap, delim, fp) == strslen[0]);
ATF_REQUIRE_STREQ(strs[0], line);
ATF_REQUIRE(getdelim(&line, &linecap, delim, fp) == strslen[1]);
ATF_REQUIRE_STREQ(strs[1], line);
ATF_REQUIRE_ERRNO(EAGAIN,
(linelen = getdelim(&line, &linecap, delim, fp)) == -1);
ATF_REQUIRE_STREQ("", line);
ATF_REQUIRE(ferror(fp));
ATF_REQUIRE(!feof(fp));
clearerr(fp);
ipc_wakeup(ipcfd);
/* Wait for the partial write to be completed and another to be done. */
ipc_wait(ipcfd);
ATF_REQUIRE((linelen = getdelim(&line, &linecap, delim, fp)) != -1);
ATF_REQUIRE(!ferror(fp));
ATF_REQUIRE(!feof(fp));
ATF_REQUIRE_STREQ(strs[2], line);
ATF_REQUIRE(linelen == strslen[2]);
ATF_REQUIRE_ERRNO(EAGAIN,
(linelen = getdelim(&line, &linecap, delim, fp)) == -1);
ATF_REQUIRE_STREQ("", line);
ATF_REQUIRE(ferror(fp));
ATF_REQUIRE(!feof(fp));
clearerr(fp);
ipc_wakeup(ipcfd);
ipc_wait(ipcfd);
ATF_REQUIRE((linelen = getdelim(&line, &linecap, delim, fp)) != -1);
ATF_REQUIRE(!ferror(fp));
ATF_REQUIRE(!feof(fp));
ATF_REQUIRE_STREQ(strs[3], line);
ATF_REQUIRE(linelen == strslen[3]);
ATF_REQUIRE(waitpid(pid, &status, WEXITED) != -1);
ATF_REQUIRE(WIFEXITED(status));
ATF_REQUIRE(WEXITSTATUS(status) == 0);
}
ATF_TC_WITHOUT_HEAD(nonblock_eagain_buffered);
ATF_TC_BODY(nonblock_eagain_buffered, tc)
{
_nonblock_eagain(_IOFBF);
}
ATF_TC_WITHOUT_HEAD(nonblock_eagain_unbuffered);
ATF_TC_BODY(nonblock_eagain_unbuffered, tc)
{
_nonblock_eagain(_IONBF);
}
ATF_TP_ADD_TCS(tp)
{
ATF_TP_ADD_TC(tp, getline_basic);
ATF_TP_ADD_TC(tp, stream_error);
ATF_TP_ADD_TC(tp, eof);
ATF_TP_ADD_TC(tp, invalid_params);
ATF_TP_ADD_TC(tp, nul);
ATF_TP_ADD_TC(tp, empty_NULL_buffer);
ATF_TP_ADD_TC(tp, nonblock_eagain_unbuffered);
ATF_TP_ADD_TC(tp, nonblock_eagain_buffered);
return (atf_no_error());
}