/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.haxx.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
***************************************************************************/
#include "test.h"
#ifdef HAVE_SYS_RESOURCE_H
#include <sys/resource.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#include <limits.h>
#include "warnless.h"
#include "memdebug.h"
#if !defined(HAVE_POLL_FINE) && \
!defined(USE_WINSOCK) && \
!defined(TPF) && \
!defined(FD_SETSIZE)
#error "this test requires FD_SETSIZE"
#endif
#define SAFETY_MARGIN (11)
#if defined(WIN32) || defined(_WIN32) || defined(MSDOS)
#define DEV_NULL "NUL"
#else
#define DEV_NULL "/dev/null"
#endif
#if defined(HAVE_GETRLIMIT) && defined(HAVE_SETRLIMIT)
static int *fd = NULL;
static struct rlimit num_open;
static char msgbuff[256];
static void store_errmsg(const char *msg, int err)
{
if(!err)
snprintf(msgbuff, sizeof(msgbuff), "%s", msg);
else
snprintf(msgbuff, sizeof(msgbuff), "%s, errno %d, %s", msg, err,
strerror(err));
}
static void close_file_descriptors(void)
{
for(num_open.rlim_cur = 0;
num_open.rlim_cur < num_open.rlim_max;
num_open.rlim_cur++)
if(fd[num_open.rlim_cur] > 0)
close(fd[num_open.rlim_cur]);
free(fd);
fd = NULL;
}
static int fopen_works(void)
{
FILE *fpa[3];
int i;
int ret = 1;
for(i = 0; i < 3; i++) {
fpa[i] = NULL;
}
for(i = 0; i < 3; i++) {
fpa[i] = fopen(DEV_NULL, FOPEN_READTEXT);
if(fpa[i] == NULL) {
store_errmsg("fopen failed", errno);
fprintf(stderr, "%s\n", msgbuff);
ret = 0;
break;
}
}
for(i = 0; i < 3; i++) {
if(fpa[i] != NULL)
fclose(fpa[i]);
}
return ret;
}
static int rlimit(int keep_open)
{
int *tmpfd;
rlim_t nitems, i;
int *memchunk = NULL;
char *fmt;
struct rlimit rl;
char strbuff[256];
char strbuff1[81];
char fmt_u[] = "%u";
char fmt_lu[] = "%lu";
#ifdef HAVE_LONGLONG
char fmt_llu[] = "%llu";
if(sizeof(rl.rlim_max) > sizeof(long))
fmt = fmt_llu;
else
#endif
fmt = (sizeof(rl.rlim_max) < sizeof(long))?fmt_u:fmt_lu;
/* get initial open file limits */
if(getrlimit(RLIMIT_NOFILE, &rl) != 0) {
store_errmsg("getrlimit() failed", errno);
fprintf(stderr, "%s\n", msgbuff);
return -1;
}
/* show initial open file limits */
#ifdef RLIM_INFINITY
if(rl.rlim_cur == RLIM_INFINITY)
strcpy(strbuff, "INFINITY");
else
#endif
snprintf(strbuff, sizeof(strbuff), fmt, rl.rlim_cur);
fprintf(stderr, "initial soft limit: %s\n", strbuff);
#ifdef RLIM_INFINITY
if(rl.rlim_max == RLIM_INFINITY)
strcpy(strbuff, "INFINITY");
else
#endif
snprintf(strbuff, sizeof(strbuff), fmt, rl.rlim_max);
fprintf(stderr, "initial hard limit: %s\n", strbuff);
/*
* if soft limit and hard limit are different we ask the
* system to raise soft limit all the way up to the hard
* limit. Due to some other system limit the soft limit
* might not be raised up to the hard limit. So from this
* point the resulting soft limit is our limit. Trying to
* open more than soft limit file descriptors will fail.
*/
if(rl.rlim_cur != rl.rlim_max) {
#ifdef OPEN_MAX
if((rl.rlim_cur > 0) &&
(rl.rlim_cur < OPEN_MAX)) {
fprintf(stderr, "raising soft limit up to OPEN_MAX\n");
rl.rlim_cur = OPEN_MAX;
if(setrlimit(RLIMIT_NOFILE, &rl) != 0) {
/* on failure don't abort just issue a warning */
store_errmsg("setrlimit() failed", errno);
fprintf(stderr, "%s\n", msgbuff);
msgbuff[0] = '\0';
}
}
#endif
fprintf(stderr, "raising soft limit up to hard limit\n");
rl.rlim_cur = rl.rlim_max;
if(setrlimit(RLIMIT_NOFILE, &rl) != 0) {
/* on failure don't abort just issue a warning */
store_errmsg("setrlimit() failed", errno);
fprintf(stderr, "%s\n", msgbuff);
msgbuff[0] = '\0';
}
/* get current open file limits */
if(getrlimit(RLIMIT_NOFILE, &rl) != 0) {
store_errmsg("getrlimit() failed", errno);
fprintf(stderr, "%s\n", msgbuff);
return -3;
}
/* show current open file limits */
#ifdef RLIM_INFINITY
if(rl.rlim_cur == RLIM_INFINITY)
strcpy(strbuff, "INFINITY");
else
#endif
snprintf(strbuff, sizeof(strbuff), fmt, rl.rlim_cur);
fprintf(stderr, "current soft limit: %s\n", strbuff);
#ifdef RLIM_INFINITY
if(rl.rlim_max == RLIM_INFINITY)
strcpy(strbuff, "INFINITY");
else
#endif
snprintf(strbuff, sizeof(strbuff), fmt, rl.rlim_max);
fprintf(stderr, "current hard limit: %s\n", strbuff);
} /* (rl.rlim_cur != rl.rlim_max) */
/*
* test 537 is all about testing libcurl functionality
* when the system has nearly exhausted the number of
* available file descriptors. Test 537 will try to run
* with a very small number of file descriptors available.
* This implies that any file descriptor which is open
* when the test runs will have a number in the high range
* of whatever the system supports.
*/
/*
* reserve a chunk of memory before opening file descriptors to
* avoid a low memory condition once the file descriptors are
* open. System conditions that could make the test fail should
* be addressed in the precheck phase. This chunk of memory shall
* be always free()ed before exiting the rlimit() function so
* that it becomes available to the test.
*/
for(nitems = i = 1; nitems <= i; i *= 2)
nitems = i;
if(nitems > 0x7fff)
nitems = 0x40000;
do {
num_open.rlim_max = sizeof(*memchunk) * nitems;
snprintf(strbuff, sizeof(strbuff), fmt, num_open.rlim_max);
fprintf(stderr, "allocating memchunk %s byte array\n", strbuff);
memchunk = malloc(sizeof(*memchunk) * (size_t)nitems);
if(!memchunk) {
fprintf(stderr, "memchunk, malloc() failed\n");
nitems /= 2;
}
} while(nitems && !memchunk);
if(!memchunk) {
store_errmsg("memchunk, malloc() failed", errno);
fprintf(stderr, "%s\n", msgbuff);
return -4;
}
/* initialize it to fight lazy allocation */
fprintf(stderr, "initializing memchunk array\n");
for(i = 0; i < nitems; i++)
memchunk[i] = -1;
/* set the number of file descriptors we will try to open */
#ifdef RLIM_INFINITY
if((rl.rlim_cur > 0) && (rl.rlim_cur != RLIM_INFINITY)) {
#else
if(rl.rlim_cur > 0) {
#endif
/* soft limit minus SAFETY_MARGIN */
num_open.rlim_max = rl.rlim_cur - SAFETY_MARGIN;
}
else {
/* a huge number of file descriptors */
for(nitems = i = 1; nitems <= i; i *= 2)
nitems = i;
if(nitems > 0x7fff)
nitems = 0x40000;
num_open.rlim_max = nitems;
}
/* verify that we won't overflow size_t in malloc() */
if((size_t)(num_open.rlim_max) > ((size_t)-1) / sizeof(*fd)) {
snprintf(strbuff1, sizeof(strbuff1), fmt, num_open.rlim_max);
snprintf(strbuff, sizeof(strbuff), "unable to allocate an array for %s "
"file descriptors, would overflow size_t", strbuff1);
store_errmsg(strbuff, 0);
fprintf(stderr, "%s\n", msgbuff);
free(memchunk);
return -5;
}
/* allocate array for file descriptors */
do {
snprintf(strbuff, sizeof(strbuff), fmt, num_open.rlim_max);
fprintf(stderr, "allocating array for %s file descriptors\n", strbuff);
fd = malloc(sizeof(*fd) * (size_t)(num_open.rlim_max));
if(!fd) {
fprintf(stderr, "fd, malloc() failed\n");
num_open.rlim_max /= 2;
}
} while(num_open.rlim_max && !fd);
if(!fd) {
store_errmsg("fd, malloc() failed", errno);
fprintf(stderr, "%s\n", msgbuff);
free(memchunk);
return -6;
}
/* initialize it to fight lazy allocation */
fprintf(stderr, "initializing fd array\n");
for(num_open.rlim_cur = 0;
num_open.rlim_cur < num_open.rlim_max;
num_open.rlim_cur++)
fd[num_open.rlim_cur] = -1;
snprintf(strbuff, sizeof(strbuff), fmt, num_open.rlim_max);
fprintf(stderr, "trying to open %s file descriptors\n", strbuff);
/* open a dummy descriptor */
fd[0] = open(DEV_NULL, O_RDONLY);
if(fd[0] < 0) {
snprintf(strbuff, sizeof(strbuff), "opening of %s failed", DEV_NULL);
store_errmsg(strbuff, errno);
fprintf(stderr, "%s\n", msgbuff);
free(fd);
fd = NULL;
free(memchunk);
return -7;
}
/* create a bunch of file descriptors */
for(num_open.rlim_cur = 1;
num_open.rlim_cur < num_open.rlim_max;
num_open.rlim_cur++) {
fd[num_open.rlim_cur] = dup(fd[0]);
if(fd[num_open.rlim_cur] < 0) {
fd[num_open.rlim_cur] = -1;
snprintf(strbuff1, sizeof(strbuff1), fmt, num_open.rlim_cur);
snprintf(strbuff, sizeof(strbuff), "dup() attempt %s failed", strbuff1);
fprintf(stderr, "%s\n", strbuff);
snprintf(strbuff1, sizeof(strbuff1), fmt, num_open.rlim_cur);
snprintf(strbuff, sizeof(strbuff), "fds system limit seems close to %s",
strbuff1);
fprintf(stderr, "%s\n", strbuff);
num_open.rlim_max = num_open.rlim_cur - SAFETY_MARGIN;
num_open.rlim_cur -= num_open.rlim_max;
snprintf(strbuff1, sizeof(strbuff1), fmt, num_open.rlim_cur);
snprintf(strbuff, sizeof(strbuff), "closing %s file descriptors",
strbuff1);
fprintf(stderr, "%s\n", strbuff);
for(num_open.rlim_cur = num_open.rlim_max;
fd[num_open.rlim_cur] >= 0;
num_open.rlim_cur++) {
close(fd[num_open.rlim_cur]);
fd[num_open.rlim_cur] = -1;
}
snprintf(strbuff, sizeof(strbuff), fmt, num_open.rlim_max);
fprintf(stderr, "shrinking array for %s file descriptors\n", strbuff);
/* we don't care if we can't shrink it */
tmpfd = realloc(fd, sizeof(*fd) * (size_t)(num_open.rlim_max));
if(tmpfd) {
fd = tmpfd;
tmpfd = NULL;
}
break;
}
}
snprintf(strbuff, sizeof(strbuff), fmt, num_open.rlim_max);
fprintf(stderr, "%s file descriptors open\n", strbuff);
#if !defined(HAVE_POLL_FINE) && \
!defined(USE_WINSOCK) && \
!defined(TPF)
/*
* when using select() instead of poll() we cannot test
* libcurl functionality with a socket number equal or
* greater than FD_SETSIZE. In any case, macro VERIFY_SOCK
* in lib/select.c enforces this check and protects libcurl
* from a possible crash. The effect of this protection
* is that test 537 will always fail, since the actual
* call to select() never takes place. We skip test 537
* with an indication that select limit would be exceeded.
*/
num_open.rlim_cur = FD_SETSIZE - SAFETY_MARGIN;
if(num_open.rlim_max > num_open.rlim_cur) {
snprintf(strbuff, sizeof(strbuff), "select limit is FD_SETSIZE %d",
FD_SETSIZE);
store_errmsg(strbuff, 0);
fprintf(stderr, "%s\n", msgbuff);
close_file_descriptors();
free(memchunk);
return -8;
}
num_open.rlim_cur = FD_SETSIZE - SAFETY_MARGIN;
for(rl.rlim_cur = 0;
rl.rlim_cur < num_open.rlim_max;
rl.rlim_cur++) {
if((fd[rl.rlim_cur] > 0) &&
((unsigned int)fd[rl.rlim_cur] > num_open.rlim_cur)) {
snprintf(strbuff, sizeof(strbuff), "select limit is FD_SETSIZE %d",
FD_SETSIZE);
store_errmsg(strbuff, 0);
fprintf(stderr, "%s\n", msgbuff);
close_file_descriptors();
free(memchunk);
return -9;
}
}
#endif /* using a FD_SETSIZE bound select() */
/*
* Old or 'backwards compatible' implementations of stdio do not allow
* handling of streams with an underlying file descriptor number greater
* than 255, even when allowing high numbered file descriptors for sockets.
* At this point we have a big number of file descriptors which have been
* opened using dup(), so lets test the stdio implementation and discover
* if it is capable of fopen()ing some additional files.
*/
if(!fopen_works()) {
snprintf(strbuff1, sizeof(strbuff1), fmt, num_open.rlim_max);
snprintf(strbuff, sizeof(strbuff), "fopen fails with %s fds open",
strbuff1);
fprintf(stderr, "%s\n", msgbuff);
snprintf(strbuff, sizeof(strbuff), "fopen fails with lots of fds open");
store_errmsg(strbuff, 0);
close_file_descriptors();
free(memchunk);
return -10;
}
/* free the chunk of memory we were reserving so that it
becomes becomes available to the test */
free(memchunk);
/* close file descriptors unless instructed to keep them */
if(!keep_open) {
close_file_descriptors();
}
return 0;
}
int test(char *URL)
{
CURLcode res;
CURL *curl;
if(!strcmp(URL, "check")) {
/* used by the test script to ask if we can run this test or not */
if(rlimit(FALSE)) {
fprintf(stdout, "rlimit problem: %s\n", msgbuff);
return 1;
}
return 0; /* sure, run this! */
}
if(rlimit(TRUE)) {
/* failure */
return TEST_ERR_MAJOR_BAD;
}
/* run the test with the bunch of open file descriptors
and close them all once the test is over */
if(curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK) {
fprintf(stderr, "curl_global_init() failed\n");
close_file_descriptors();
return TEST_ERR_MAJOR_BAD;
}
curl = curl_easy_init();
if(!curl) {
fprintf(stderr, "curl_easy_init() failed\n");
close_file_descriptors();
curl_global_cleanup();
return TEST_ERR_MAJOR_BAD;
}
test_setopt(curl, CURLOPT_URL, URL);
test_setopt(curl, CURLOPT_HEADER, 1L);
res = curl_easy_perform(curl);
test_cleanup:
close_file_descriptors();
curl_easy_cleanup(curl);
curl_global_cleanup();
return (int)res;
}
#else /* defined(HAVE_GETRLIMIT) && defined(HAVE_SETRLIMIT) */
int test(char *URL)
{
(void)URL;
printf("system lacks necessary system function(s)");
return 1; /* skip test */
}
#endif /* defined(HAVE_GETRLIMIT) && defined(HAVE_SETRLIMIT) */