1/***************************************************************************
2 *                                  _   _ ____  _
3 *  Project                     ___| | | |  _ \| |
4 *                             / __| | | | |_) | |
5 *                            | (__| |_| |  _ <| |___
6 *                             \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2013, Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at http://curl.haxx.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 ***************************************************************************/
22#include "test.h"
23
24#ifdef HAVE_SYS_RESOURCE_H
25#include <sys/resource.h>
26#endif
27#ifdef HAVE_FCNTL_H
28#include <fcntl.h>
29#endif
30#ifdef HAVE_LIMITS_H
31#include <limits.h>
32#endif
33
34#include "warnless.h"
35#include "memdebug.h"
36
37#if !defined(HAVE_POLL_FINE)    && \
38    !defined(USE_WINSOCK)       && \
39    !defined(TPF)               && \
40    !defined(FD_SETSIZE)
41#error "this test requires FD_SETSIZE"
42#endif
43
44#define SAFETY_MARGIN (11)
45
46#if defined(WIN32) || defined(_WIN32) || defined(MSDOS)
47#define DEV_NULL "NUL"
48#else
49#define DEV_NULL "/dev/null"
50#endif
51
52#if defined(HAVE_GETRLIMIT) && defined(HAVE_SETRLIMIT)
53
54static int *fd = NULL;
55static struct rlimit num_open;
56static char msgbuff[256];
57
58static void store_errmsg(const char *msg, int err)
59{
60  if (!err)
61    sprintf(msgbuff, "%s", msg);
62  else
63    sprintf(msgbuff, "%s, errno %d, %s", msg, err, strerror(err));
64}
65
66static void close_file_descriptors(void)
67{
68  for (num_open.rlim_cur = 0;
69       num_open.rlim_cur < num_open.rlim_max;
70       num_open.rlim_cur++)
71    if (fd[num_open.rlim_cur] > 0)
72      close(fd[num_open.rlim_cur]);
73  free(fd);
74  fd = NULL;
75}
76
77static int fopen_works(void)
78{
79  FILE *fpa[3];
80  int i;
81  int ret = 1;
82
83  for (i = 0; i < 3; i++) {
84    fpa[i] = NULL;
85  }
86  for (i = 0; i < 3; i++) {
87    fpa[i] = fopen(DEV_NULL, "r");
88    if (fpa[i] == NULL) {
89      store_errmsg("fopen() failed", ERRNO);
90      fprintf(stderr, "%s\n", msgbuff);
91      ret = 0;
92      break;
93    }
94  }
95  for (i = 0; i < 3; i++) {
96    if (fpa[i] != NULL)
97      fclose(fpa[i]);
98  }
99  return ret;
100}
101
102static int rlimit(int keep_open)
103{
104  int *tmpfd;
105  int nitems, i;
106  int *memchunk = NULL;
107  char *fmt;
108  struct rlimit rl;
109  char strbuff[256];
110  char strbuff1[81];
111  char fmt_u[] = "%u";
112  char fmt_lu[] = "%lu";
113#ifdef HAVE_LONGLONG
114  char fmt_llu[] = "%llu";
115
116  if (sizeof(rl.rlim_max) > sizeof(long))
117    fmt = fmt_llu;
118  else
119#endif
120    fmt = (sizeof(rl.rlim_max) < sizeof(long))?fmt_u:fmt_lu;
121
122  /* get initial open file limits */
123
124  if (getrlimit(RLIMIT_NOFILE, &rl) != 0) {
125    store_errmsg("getrlimit() failed", ERRNO);
126    fprintf(stderr, "%s\n", msgbuff);
127    return -1;
128  }
129
130  /* show initial open file limits */
131
132#ifdef RLIM_INFINITY
133  if (rl.rlim_cur == RLIM_INFINITY)
134    strcpy(strbuff, "INFINITY");
135  else
136#endif
137    sprintf(strbuff, fmt, rl.rlim_cur);
138  fprintf(stderr, "initial soft limit: %s\n", strbuff);
139
140#ifdef RLIM_INFINITY
141  if (rl.rlim_max == RLIM_INFINITY)
142    strcpy(strbuff, "INFINITY");
143  else
144#endif
145    sprintf(strbuff, fmt, rl.rlim_max);
146  fprintf(stderr, "initial hard limit: %s\n", strbuff);
147
148  /*
149   * if soft limit and hard limit are different we ask the
150   * system to raise soft limit all the way up to the hard
151   * limit. Due to some other system limit the soft limit
152   * might not be raised up to the hard limit. So from this
153   * point the resulting soft limit is our limit. Trying to
154   * open more than soft limit file descriptors will fail.
155   */
156
157  if (rl.rlim_cur != rl.rlim_max) {
158
159#ifdef OPEN_MAX
160    if ((rl.rlim_cur > 0) &&
161        (rl.rlim_cur < OPEN_MAX)) {
162      fprintf(stderr, "raising soft limit up to OPEN_MAX\n");
163      rl.rlim_cur = OPEN_MAX;
164      if (setrlimit(RLIMIT_NOFILE, &rl) != 0) {
165        /* on failure don't abort just issue a warning */
166        store_errmsg("setrlimit() failed", ERRNO);
167        fprintf(stderr, "%s\n", msgbuff);
168        msgbuff[0] = '\0';
169      }
170    }
171#endif
172
173    fprintf(stderr, "raising soft limit up to hard limit\n");
174    rl.rlim_cur = rl.rlim_max;
175    if (setrlimit(RLIMIT_NOFILE, &rl) != 0) {
176      /* on failure don't abort just issue a warning */
177      store_errmsg("setrlimit() failed", ERRNO);
178      fprintf(stderr, "%s\n", msgbuff);
179      msgbuff[0] = '\0';
180    }
181
182    /* get current open file limits */
183
184    if (getrlimit(RLIMIT_NOFILE, &rl) != 0) {
185      store_errmsg("getrlimit() failed", ERRNO);
186      fprintf(stderr, "%s\n", msgbuff);
187      return -3;
188    }
189
190    /* show current open file limits */
191
192#ifdef RLIM_INFINITY
193    if (rl.rlim_cur == RLIM_INFINITY)
194      strcpy(strbuff, "INFINITY");
195    else
196#endif
197      sprintf(strbuff, fmt, rl.rlim_cur);
198    fprintf(stderr, "current soft limit: %s\n", strbuff);
199
200#ifdef RLIM_INFINITY
201    if (rl.rlim_max == RLIM_INFINITY)
202      strcpy(strbuff, "INFINITY");
203    else
204#endif
205      sprintf(strbuff, fmt, rl.rlim_max);
206    fprintf(stderr, "current hard limit: %s\n", strbuff);
207
208  } /* (rl.rlim_cur != rl.rlim_max) */
209
210  /*
211   * test 537 is all about testing libcurl functionality
212   * when the system has nearly exhausted the number of
213   * available file descriptors. Test 537 will try to run
214   * with a very small number of file descriptors available.
215   * This implies that any file descriptor which is open
216   * when the test runs will have a number in the high range
217   * of whatever the system supports.
218   */
219
220  /*
221   * reserve a chunk of memory before opening file descriptors to
222   * avoid a low memory condition once the file descriptors are
223   * open. System conditions that could make the test fail should
224   * be addressed in the precheck phase. This chunk of memory shall
225   * be always free()ed before exiting the rlimit() function so
226   * that it becomes available to the test.
227   */
228
229  for (nitems = i = 1; nitems <= i; i *= 2)
230    nitems = i;
231  if (nitems > 0x7fff)
232    nitems = 0x40000;
233  do {
234    num_open.rlim_max = sizeof(*memchunk) * (size_t)nitems;
235    sprintf(strbuff, fmt, num_open.rlim_max);
236    fprintf(stderr, "allocating memchunk %s byte array\n", strbuff);
237    memchunk = malloc(sizeof(*memchunk) * (size_t)nitems);
238    if (!memchunk) {
239      fprintf(stderr, "memchunk, malloc() failed\n");
240      nitems /= 2;
241    }
242  } while (nitems && !memchunk);
243  if (!memchunk) {
244    store_errmsg("memchunk, malloc() failed", ERRNO);
245    fprintf(stderr, "%s\n", msgbuff);
246    return -4;
247  }
248
249  /* initialize it to fight lazy allocation */
250
251  fprintf(stderr, "initializing memchunk array\n");
252
253  for (i = 0; i < nitems; i++)
254    memchunk[i] = -1;
255
256  /* set the number of file descriptors we will try to open */
257
258#ifdef RLIM_INFINITY
259  if ((rl.rlim_cur > 0) && (rl.rlim_cur != RLIM_INFINITY)) {
260#else
261  if (rl.rlim_cur > 0) {
262#endif
263    /* soft limit minus SAFETY_MARGIN */
264    num_open.rlim_max = rl.rlim_cur - SAFETY_MARGIN;
265  }
266  else {
267    /* a huge number of file descriptors */
268    for (nitems = i = 1; nitems <= i; i *= 2)
269      nitems = i;
270    if (nitems > 0x7fff)
271      nitems = 0x40000;
272    num_open.rlim_max = nitems;
273  }
274
275  /* verify that we won't overflow size_t in malloc() */
276
277  if ((size_t)(num_open.rlim_max) > ((size_t)-1) / sizeof(*fd)) {
278    sprintf(strbuff1, fmt, num_open.rlim_max);
279    sprintf(strbuff, "unable to allocate an array for %s "
280            "file descriptors, would overflow size_t", strbuff1);
281    store_errmsg(strbuff, 0);
282    fprintf(stderr, "%s\n", msgbuff);
283    free(memchunk);
284    return -5;
285  }
286
287  /* allocate array for file descriptors */
288
289  do {
290    sprintf(strbuff, fmt, num_open.rlim_max);
291    fprintf(stderr, "allocating array for %s file descriptors\n", strbuff);
292    fd = malloc(sizeof(*fd) * (size_t)(num_open.rlim_max));
293    if (!fd) {
294      fprintf(stderr, "fd, malloc() failed\n");
295      num_open.rlim_max /= 2;
296    }
297  } while (num_open.rlim_max && !fd);
298  if (!fd) {
299    store_errmsg("fd, malloc() failed", ERRNO);
300    fprintf(stderr, "%s\n", msgbuff);
301    free(memchunk);
302    return -6;
303  }
304
305  /* initialize it to fight lazy allocation */
306
307  fprintf(stderr, "initializing fd array\n");
308
309  for (num_open.rlim_cur = 0;
310       num_open.rlim_cur < num_open.rlim_max;
311       num_open.rlim_cur++)
312    fd[num_open.rlim_cur] = -1;
313
314  sprintf(strbuff, fmt, num_open.rlim_max);
315  fprintf(stderr, "trying to open %s file descriptors\n", strbuff);
316
317  /* open a dummy descriptor */
318
319  fd[0] = open(DEV_NULL, O_RDONLY);
320  if (fd[0] < 0) {
321    sprintf(strbuff, "opening of %s failed", DEV_NULL);
322    store_errmsg(strbuff, ERRNO);
323    fprintf(stderr, "%s\n", msgbuff);
324    free(fd);
325    fd = NULL;
326    free(memchunk);
327    return -7;
328  }
329
330  /* create a bunch of file descriptors */
331
332  for (num_open.rlim_cur = 1;
333       num_open.rlim_cur < num_open.rlim_max;
334       num_open.rlim_cur++) {
335
336    fd[num_open.rlim_cur] = dup(fd[0]);
337
338    if (fd[num_open.rlim_cur] < 0) {
339
340      fd[num_open.rlim_cur] = -1;
341
342      sprintf(strbuff1, fmt, num_open.rlim_cur);
343      sprintf(strbuff, "dup() attempt %s failed", strbuff1);
344      fprintf(stderr, "%s\n", strbuff);
345
346      sprintf(strbuff1, fmt, num_open.rlim_cur);
347      sprintf(strbuff, "fds system limit seems close to %s", strbuff1);
348      fprintf(stderr, "%s\n", strbuff);
349
350      num_open.rlim_max = num_open.rlim_cur - SAFETY_MARGIN;
351
352      num_open.rlim_cur -= num_open.rlim_max;
353      sprintf(strbuff1, fmt, num_open.rlim_cur);
354      sprintf(strbuff, "closing %s file descriptors", strbuff1);
355      fprintf(stderr, "%s\n", strbuff);
356
357      for (num_open.rlim_cur = num_open.rlim_max;
358           fd[num_open.rlim_cur] >= 0;
359           num_open.rlim_cur++) {
360        close(fd[num_open.rlim_cur]);
361        fd[num_open.rlim_cur] = -1;
362      }
363
364      sprintf(strbuff, fmt, num_open.rlim_max);
365      fprintf(stderr, "shrinking array for %s file descriptors\n", strbuff);
366
367      /* we don't care if we can't shrink it */
368
369      tmpfd = realloc(fd, sizeof(*fd) * (size_t)(num_open.rlim_max));
370      if (tmpfd) {
371        fd = tmpfd;
372        tmpfd = NULL;
373      }
374
375      break;
376
377    }
378
379  }
380
381  sprintf(strbuff, fmt, num_open.rlim_max);
382  fprintf(stderr, "%s file descriptors open\n", strbuff);
383
384#if !defined(HAVE_POLL_FINE)    && \
385    !defined(USE_WINSOCK)       && \
386    !defined(TPF)
387
388  /*
389   * when using select() instead of poll() we cannot test
390   * libcurl functionality with a socket number equal or
391   * greater than FD_SETSIZE. In any case, macro VERIFY_SOCK
392   * in lib/select.c enforces this check and protects libcurl
393   * from a possible crash. The effect of this protection
394   * is that test 537 will always fail, since the actual
395   * call to select() never takes place. We skip test 537
396   * with an indication that select limit would be exceeded.
397   */
398
399  num_open.rlim_cur = FD_SETSIZE - SAFETY_MARGIN;
400  if (num_open.rlim_max > num_open.rlim_cur) {
401    sprintf(strbuff, "select limit is FD_SETSIZE %d", FD_SETSIZE);
402    store_errmsg(strbuff, 0);
403    fprintf(stderr, "%s\n", msgbuff);
404    close_file_descriptors();
405    free(memchunk);
406    return -8;
407  }
408
409  num_open.rlim_cur = FD_SETSIZE - SAFETY_MARGIN;
410  for (rl.rlim_cur = 0;
411       rl.rlim_cur < num_open.rlim_max;
412       rl.rlim_cur++) {
413    if ((fd[rl.rlim_cur] > 0) &&
414       ((unsigned int)fd[rl.rlim_cur] > num_open.rlim_cur)) {
415      sprintf(strbuff, "select limit is FD_SETSIZE %d", FD_SETSIZE);
416      store_errmsg(strbuff, 0);
417      fprintf(stderr, "%s\n", msgbuff);
418      close_file_descriptors();
419      free(memchunk);
420      return -9;
421    }
422  }
423
424#endif /* using a FD_SETSIZE bound select() */
425
426  /*
427   * Old or 'backwards compatible' implementations of stdio do not allow
428   * handling of streams with an underlying file descriptor number greater
429   * than 255, even when allowing high numbered file descriptors for sockets.
430   * At this point we have a big number of file descriptors which have been
431   * opened using dup(), so lets test the stdio implementation and discover
432   * if it is capable of fopen()ing some additional files.
433   */
434
435  if (!fopen_works()) {
436    sprintf(strbuff1, fmt, num_open.rlim_max);
437    sprintf(strbuff, "stdio fopen() fails with %s fds open()",
438            strbuff1);
439    fprintf(stderr, "%s\n", msgbuff);
440    sprintf(strbuff, "stdio fopen() fails with lots of fds open()");
441    store_errmsg(strbuff, 0);
442    close_file_descriptors();
443    free(memchunk);
444    return -10;
445  }
446
447  /* free the chunk of memory we were reserving so that it
448     becomes becomes available to the test */
449
450  free(memchunk);
451
452  /* close file descriptors unless instructed to keep them */
453
454  if (!keep_open) {
455    close_file_descriptors();
456  }
457
458  return 0;
459}
460
461int test(char *URL)
462{
463  CURLcode res;
464  CURL *curl;
465
466  if(!strcmp(URL, "check")) {
467    /* used by the test script to ask if we can run this test or not */
468    if(rlimit(FALSE)) {
469      fprintf(stdout, "rlimit problem: %s\n", msgbuff);
470      return 1;
471    }
472    return 0; /* sure, run this! */
473  }
474
475  if (rlimit(TRUE)) {
476    /* failure */
477    return TEST_ERR_MAJOR_BAD;
478  }
479
480  /* run the test with the bunch of open file descriptors
481     and close them all once the test is over */
482
483  if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK) {
484    fprintf(stderr, "curl_global_init() failed\n");
485    close_file_descriptors();
486    return TEST_ERR_MAJOR_BAD;
487  }
488
489  if ((curl = curl_easy_init()) == NULL) {
490    fprintf(stderr, "curl_easy_init() failed\n");
491    close_file_descriptors();
492    curl_global_cleanup();
493    return TEST_ERR_MAJOR_BAD;
494  }
495
496  test_setopt(curl, CURLOPT_URL, URL);
497  test_setopt(curl, CURLOPT_HEADER, 1L);
498
499  res = curl_easy_perform(curl);
500
501test_cleanup:
502
503  close_file_descriptors();
504  curl_easy_cleanup(curl);
505  curl_global_cleanup();
506
507  return (int)res;
508}
509
510#else /* defined(HAVE_GETRLIMIT) && defined(HAVE_SETRLIMIT) */
511
512int test(char *URL)
513{
514  (void)URL;
515  printf("system lacks necessary system function(s)");
516  return 1; /* skip test */
517}
518
519#endif /* defined(HAVE_GETRLIMIT) && defined(HAVE_SETRLIMIT) */
520