update and split test cases 518 and 537 into its own source code file

3 files changed, 447 insertions, 167 deletions

diff --git a/tests/libtest/Makefile.am b/tests/libtest/Makefile.am
index eb936eb48..aadd9c7ed 100644
--- a/tests/libtest/Makefile.am
+++ b/tests/libtest/Makefile.am
@@ -103,7 +103,6 @@ lib517_SOURCES = lib517.c $(SUPPORTFILES)
 lib517_DEPENDENCIES = $(DEPENDENCIES)
 
 lib518_SOURCES = lib518.c $(SUPPORTFILES)
-lib518_CFLAGS = -DLIB518
 lib518_DEPENDENCIES = $(DEPENDENCIES)
 
 lib519_SOURCES = lib519.c $(SUPPORTFILES)
@@ -150,7 +149,6 @@ lib533_DEPENDENCIES = $(DEPENDENCIES)
 lib536_SOURCES = lib536.c $(SUPPORTFILES)
 lib536_DEPENDENCIES = $(DEPENDENCIES)
 
-lib537_SOURCES = lib518.c $(SUPPORTFILES)
-lib537_CFLAGS = -DLIB537
+lib537_SOURCES = lib537.c $(SUPPORTFILES)
 lib537_DEPENDENCIES = $(DEPENDENCIES)
 
diff --git a/tests/libtest/lib518.c b/tests/libtest/lib518.c
index 0edfb3a85..cff412010 100644
--- a/tests/libtest/lib518.c
+++ b/tests/libtest/lib518.c
@@ -8,56 +8,31 @@
  * $Id$
  */
 
-/*
- * This source code is used for lib518 and lib537.
- */
-
 #include "test.h"
 
 #ifdef HAVE_SYS_TYPES_H
 #include <sys/types.h>
 #endif
-#ifdef HAVE_SYS_STAT_H
-#include <sys/stat.h>
-#endif
-#ifdef HAVE_SYS_TIME_H
-#include <sys/time.h>
-#endif
 #ifdef HAVE_SYS_RESOURCE_H
 #include <sys/resource.h>
 #endif
 #ifdef HAVE_FCNTL_H
 #include <fcntl.h>
 #endif
-#ifdef HAVE_UNISTD_H
-#include <unistd.h>
-#endif
 #ifdef HAVE_LIMITS_H
 #include <limits.h>
 #endif
-
-#define _MPRINTF_REPLACE /* use our functions only */
-#include <mprintf.h>
-
-#ifdef HAVE_SYS_SELECT_H
-#include <sys/select.h>
+#ifdef HAVE_STRING_H
+#include <string.h>
 #endif
 
-#if defined(LIB518) && !defined(FD_SETSIZE)
+#ifndef FD_SETSIZE
 #error "this test requires FD_SETSIZE"
 #endif
 
-#ifdef LIB518
-#define SAFETY_MARGIN 16
-#define NUM_OPEN (FD_SETSIZE + 10)
-#define NUM_NEEDED (NUM_OPEN + SAFETY_MARGIN)
-#endif
-
-#ifdef LIB537
-#define SAFETY_MARGIN 5
-#endif
-
-#define MEMCHUNK_NITEMS 32000
+#define SAFETY_MARGIN (16)
+#define NUM_OPEN      (FD_SETSIZE + 10)
+#define NUM_NEEDED    (NUM_OPEN + SAFETY_MARGIN)
 
 #if defined(WIN32) || defined(_WIN32) || defined(MSDOS)
 #define DEV_NULL "NUL"
@@ -88,38 +63,31 @@ static int our_errno(void)
 static void store_errmsg(const char *msg, int err)
 {
   if (!err)
-    snprintf(msgbuff, sizeof(msgbuff), "%s", msg);
+    sprintf(msgbuff, "%s", msg);
   else
-    snprintf(msgbuff, sizeof(msgbuff), "%s, errno %d, %s",
-             msg, err, strerror(err));
+    sprintf(msgbuff, "%s, errno %d, %s", msg, err, strerror(err));
 }
 
 static void close_file_descriptors(void)
 {
-  fprintf(stderr, "closing file descriptors\n");
   for (num_open.rlim_cur = 0;
        num_open.rlim_cur < num_open.rlim_max;
        num_open.rlim_cur++)
-    close(fd[num_open.rlim_cur]);
+    if (fd[num_open.rlim_cur] > 0)
+      close(fd[num_open.rlim_cur]);
   free(fd);
   fd = NULL;
-  fprintf(stderr, "file descriptors closed\n");
 }
 
 static int rlimit(int keep_open)
 {
-#ifdef LIB537
-  int *tmpfd;
-#endif
-  int i;
+  int nitems, i;
   int *memchunk = NULL;
   char *fmt;
   struct rlimit rl;
   char strbuff[256];
   char strbuff1[81];
-#ifdef LIB518
   char strbuff2[81];
-#endif
   char fmt_u[] = "%u";
   char fmt_lu[] = "%lu";
 #ifdef HAVE_LONGLONG
@@ -146,7 +114,7 @@ static int rlimit(int keep_open)
     strcpy(strbuff, "INFINITY");
   else
 #endif
-    snprintf(strbuff, sizeof(strbuff), fmt, rl.rlim_cur);
+    sprintf(strbuff, fmt, rl.rlim_cur);
   fprintf(stderr, "initial soft limit: %s\n", strbuff);
 
 #ifdef RLIM_INFINITY
@@ -154,16 +122,14 @@ static int rlimit(int keep_open)
     strcpy(strbuff, "INFINITY");
   else
 #endif
-    snprintf(strbuff, sizeof(strbuff), fmt, rl.rlim_max);
+    sprintf(strbuff, fmt, rl.rlim_max);
   fprintf(stderr, "initial hard limit: %s\n", strbuff);
 
-#ifdef LIB518
   /* show our constants */
 
   fprintf(stderr, "test518 FD_SETSIZE: %d\n", FD_SETSIZE);
   fprintf(stderr, "test518 NUM_OPEN  : %d\n", NUM_OPEN);
   fprintf(stderr, "test518 NUM_NEEDED: %d\n", NUM_NEEDED);
-#endif
 
   /*
    * if soft limit and hard limit are different we ask the
@@ -199,7 +165,7 @@ static int rlimit(int keep_open)
       strcpy(strbuff, "INFINITY");
     else
 #endif
-      snprintf(strbuff, sizeof(strbuff), fmt, rl.rlim_cur);
+      sprintf(strbuff, fmt, rl.rlim_cur);
     fprintf(stderr, "current soft limit: %s\n", strbuff);
 
 #ifdef RLIM_INFINITY
@@ -207,7 +173,7 @@ static int rlimit(int keep_open)
       strcpy(strbuff, "INFINITY");
     else
 #endif
-      snprintf(strbuff, sizeof(strbuff), fmt, rl.rlim_max);
+      sprintf(strbuff, fmt, rl.rlim_max);
     fprintf(stderr, "current hard limit: %s\n", strbuff);
 
   } /* (rl.rlim_cur != rl.rlim_max) */
@@ -218,15 +184,8 @@ static int rlimit(int keep_open)
    * This means that if for any reason we are not able to
    * open more than FD_SETSIZE file descriptors then test
    * 518 should not be run.
-   *
-   * test 537 is all about testing libcurl functionality
-   * when the system has nearly exhausted the number of
-   * free file descriptors. Test 537 will try to run with 
-   * very few free file descriptors.
    */
 
-#ifdef LIB518
-
   /*
    * verify that soft limit is higher than NUM_NEEDED,
    * number of file descriptors we would try to open
@@ -240,17 +199,15 @@ static int rlimit(int keep_open)
      (rl.rlim_cur != RLIM_INFINITY) &&
 #endif
      (rl.rlim_cur <= num_open.rlim_cur)) {
-    snprintf(strbuff2, sizeof(strbuff2), fmt, rl.rlim_cur);
-    snprintf(strbuff1, sizeof(strbuff1), fmt, num_open.rlim_cur);
-    snprintf(strbuff, sizeof(strbuff), "fd needed (%s) > "
-             "system limit (%s)", strbuff1, strbuff2);
+    sprintf(strbuff2, fmt, rl.rlim_cur);
+    sprintf(strbuff1, fmt, num_open.rlim_cur);
+    sprintf(strbuff, "fd needed (%s) > system limit (%s)",
+            strbuff1, strbuff2);
     store_errmsg(strbuff, 0);
     fprintf(stderr, "%s\n", msgbuff);
-    return -6;
+    return -4;
   }
 
-#endif /* LIB518 */
-
   /*
    * reserve a chunk of memory before opening file descriptors to
    * avoid a low memory condition once the file descriptors are
@@ -260,7 +217,12 @@ static int rlimit(int keep_open)
    * that it becomes available to the test.
    */
 
-  memchunk = malloc(sizeof(*memchunk) * MEMCHUNK_NITEMS);
+  nitems = INT_MAX / sizeof(*memchunk);
+  do {
+    memchunk = malloc(sizeof(*memchunk) * (size_t)nitems);
+    if (!memchunk)
+      nitems /= 2;
+  } while (nitems && !memchunk);
   if (!memchunk) {
     store_errmsg("memchunk, malloc() failed", our_errno());
     fprintf(stderr, "%s\n", msgbuff);
@@ -269,44 +231,28 @@ static int rlimit(int keep_open)
 
   /* initialize it to fight lazy allocation */
 
-  for (i = 0; i < MEMCHUNK_NITEMS; i++)
+  for (i = 0; i < nitems; i++)
     memchunk[i] = -1;
 
-  /* set the number of file descriptors we will try to open to ... */
+  /* set the number of file descriptors we will try to open */
 
-#ifdef LIB518
-  /* NUM_OPEN */
   num_open.rlim_max = NUM_OPEN;
-#endif
-
-#ifdef LIB537
-#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 {
-    /* biggest file descriptor array size */
-    num_open.rlim_max = INT_MAX;
-  }
-#endif /* LIB537 */
 
   /* verify that we won't overflow size_t in malloc() */
 
   if (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);
+    sprintf(strbuff1, fmt, num_open.rlim_max);
+    sprintf(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 -8;
   }
 
-  snprintf(strbuff, sizeof(strbuff), fmt, num_open.rlim_max);
+  /* allocate array for file descriptors */
+
+  sprintf(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));
@@ -324,14 +270,14 @@ static int rlimit(int keep_open)
        num_open.rlim_cur++)
     fd[num_open.rlim_cur] = -1;
 
-  snprintf(strbuff, sizeof(strbuff), fmt, num_open.rlim_max);
+  sprintf(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);
+    sprintf(strbuff, "opening of %s failed", DEV_NULL);
     store_errmsg(strbuff, our_errno());
     fprintf(stderr, "%s\n", msgbuff);
     free(fd);
@@ -342,8 +288,6 @@ static int rlimit(int keep_open)
 
   /* create a bunch of file descriptors */
 
-#ifdef LIB518
-
   for (num_open.rlim_cur = 1; 
        num_open.rlim_cur < num_open.rlim_max; 
        num_open.rlim_cur++) {
@@ -355,19 +299,17 @@ static int rlimit(int keep_open)
       fd[num_open.rlim_cur] = -1;
 
       num_open.rlim_max = NUM_NEEDED;
-      snprintf(strbuff2, sizeof(strbuff2), fmt, num_open.rlim_max);
-      snprintf(strbuff1, sizeof(strbuff1), fmt, num_open.rlim_cur);
-      snprintf(strbuff, sizeof(strbuff), "fd needed (%s) > "
-               "system limit (%s)", strbuff2, strbuff1);
+      sprintf(strbuff2, fmt, num_open.rlim_max);
+      sprintf(strbuff1, fmt, num_open.rlim_cur);
+      sprintf(strbuff, "fd needed (%s) > system limit (%s)",
+              strbuff2, strbuff1);
       store_errmsg(strbuff, 0);
       fprintf(stderr, "%s\n", msgbuff);
 
-      fprintf(stderr, "closing file descriptors\n");
       for (num_open.rlim_cur = 0;
            fd[num_open.rlim_cur] >= 0;
            num_open.rlim_cur++)
         close(fd[num_open.rlim_cur]);
-      fprintf(stderr, "file descriptors closed\n");
       free(fd);
       fd = NULL;
       free(memchunk);
@@ -377,64 +319,7 @@ static int rlimit(int keep_open)
 
   }
 
-#endif /* LIB518 */
-
-#ifdef LIB537
-
-  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 + 2);
-      snprintf(strbuff, sizeof(strbuff), "system does not support opening "
-               "more than %s files" , strbuff1);
-      fprintf(stderr, "%s\n", strbuff);
-
-      num_open.rlim_max = num_open.rlim_cur + 2 - 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 files", 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(strbuff1), fmt, num_open.rlim_max);
-      fprintf(stderr, "shrinking array for %s file descriptors\n", strbuff);
-
-      tmpfd = realloc(fd, sizeof(*fd) * (size_t)(num_open.rlim_max));
-      if (!tmpfd) {
-        snprintf(strbuff, sizeof(strbuff), "fd, realloc() failed, "
-                 "errno %d, %s", our_errno(), strerror(our_errno()));
-        fprintf(stderr, "%s\n", strbuff);
-      }
-      else {
-        fd = tmpfd;
-        tmpfd = NULL;
-      }
-
-    }
-
-  }
-
-#endif /* LIB537 */
-
-  snprintf(strbuff, sizeof(strbuff), fmt, num_open.rlim_max);
+  sprintf(strbuff, fmt, num_open.rlim_max);
   fprintf(stderr, "%s file descriptors open\n", strbuff);
 
   /* free the chunk of memory we were reserving so that it
@@ -458,7 +343,6 @@ int test(char *URL)
   if(!strcmp(URL, "check")) {
     /* used by the test script to ask if we can run this test or not */
     if(rlimit(FALSE)) {
-      fprintf(stderr, "Previous condition prevents running this test\n");
       fprintf(stdout, "rlimit problem: %s\n", msgbuff);
       return 1;
     }
@@ -467,12 +351,9 @@ int test(char *URL)
 
   if (rlimit(TRUE)) {
     /* failure */
-    fprintf(stderr, "Previous condition aborts this test\n");
     return TEST_ERR_MAJOR_BAD;
   }
 
-  fprintf(stderr, "running test...\n");
-
   /* run the test with the bunch of open file descriptors 
      and close them all once the test is over */
 
@@ -500,12 +381,14 @@ int test(char *URL)
 
   return (int)res;
 }
-#else
-/* system lacks getrlimit() and/or setrlimit() */
+
+#else /* defined(HAVE_GETRLIMIT) && defined(HAVE_SETRLIMIT) */
+
 int test(char *URL)
 {
   (void)URL;
   printf("system lacks necessary system function(s)");
-  return 1;
+  return 1; /* skip test */
 }
-#endif
+
+#endif /* defined(HAVE_GETRLIMIT) && defined(HAVE_SETRLIMIT) */
diff --git a/tests/libtest/lib537.c b/tests/libtest/lib537.c
new file mode 100644
index 000000000..7f1d7b3e2
--- /dev/null
+++ b/tests/libtest/lib537.c
@@ -0,0 +1,399 @@
+/*****************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * $Id$
+ */
+
+/*
+ * This source code is used for lib518 and lib537.
+ */
+
+#include "test.h"
+
+#ifdef HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+#ifdef HAVE_SYS_RESOURCE_H
+#include <sys/resource.h>
+#endif
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+#ifdef HAVE_LIMITS_H
+#include <limits.h>
+#endif
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+
+#define SAFETY_MARGIN (10)
+
+#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];
+
+/*
+ * our_errno() returns the NOT *socket-related* errno (or equivalent)
+ * on this platform to hide platform specific for the calling function.
+ */
+
+static int our_errno(void)
+{
+#ifdef WIN32
+  return (int)GetLastError();
+#else
+  return errno;
+#endif
+}
+
+static void store_errmsg(const char *msg, int err)
+{
+  if (!err)
+    sprintf(msgbuff, "%s", msg);
+  else
+    sprintf(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 rlimit(int keep_open)
+{
+  int *tmpfd;
+  int 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", our_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
+    sprintf(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
+    sprintf(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) {
+
+    fprintf(stderr, "raising soft limit up to hard limit\n");
+    rl.rlim_cur = rl.rlim_max;
+    if (setrlimit(RLIMIT_NOFILE, &rl) != 0) {
+      store_errmsg("setrlimit() failed", our_errno());
+      fprintf(stderr, "%s\n", msgbuff);
+      return -2;
+    }
+
+    /* get current open file limits */
+
+    if (getrlimit(RLIMIT_NOFILE, &rl) != 0) {
+      store_errmsg("getrlimit() failed", our_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
+      sprintf(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
+      sprintf(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
+   * free file descriptors. Test 537 will try to run with 
+   * very few free file descriptors.
+   */
+
+  /*
+   * 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.
+   */
+
+  nitems = INT_MAX / sizeof(*memchunk);
+  do {
+    memchunk = malloc(sizeof(*memchunk) * (size_t)nitems);
+    if (!memchunk)
+      nitems /= 2;
+  } while (nitems && !memchunk);
+  if (!memchunk) {
+    store_errmsg("memchunk, malloc() failed", our_errno());
+    fprintf(stderr, "%s\n", msgbuff);
+    return -7;
+  }
+
+  /* initialize it to fight lazy allocation */
+
+  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 {
+    /* biggest file descriptor array size */
+    num_open.rlim_max = INT_MAX / sizeof(*fd);
+  }
+
+  /* verify that we won't overflow size_t in malloc() */
+
+  if (num_open.rlim_max > ((size_t)-1) / sizeof(*fd)) {
+    sprintf(strbuff1, fmt, num_open.rlim_max);
+    sprintf(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 -8;
+  }
+
+  /* allocate array for file descriptors */
+
+  do {
+    sprintf(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", our_errno());
+    fprintf(stderr, "%s\n", msgbuff);
+    free(memchunk);
+    return -9;
+  }
+
+  /* initialize it to fight lazy allocation */
+
+  for (num_open.rlim_cur = 0;
+       num_open.rlim_cur < num_open.rlim_max;
+       num_open.rlim_cur++)
+    fd[num_open.rlim_cur] = -1;
+
+  sprintf(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) {
+    sprintf(strbuff, "opening of %s failed", DEV_NULL);
+    store_errmsg(strbuff, our_errno());
+    fprintf(stderr, "%s\n", msgbuff);
+    free(fd);
+    fd = NULL;
+    free(memchunk);
+    return -10;
+  }
+
+  /* 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;
+
+      sprintf(strbuff1, fmt, num_open.rlim_cur);
+      sprintf(strbuff, "dup() attempt %s failed", strbuff1);
+      fprintf(stderr, "%s\n", strbuff);
+
+      sprintf(strbuff1, fmt, num_open.rlim_cur + 2);
+      sprintf(strbuff, "system does not support opening "
+              "more than %s files" , strbuff1);
+      fprintf(stderr, "%s\n", strbuff);
+
+      num_open.rlim_max = num_open.rlim_cur + 2 - SAFETY_MARGIN;
+
+      num_open.rlim_cur -= num_open.rlim_max;
+      sprintf(strbuff1, fmt, num_open.rlim_cur);
+      sprintf(strbuff, "closing %s files", 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;
+      }
+
+      sprintf(strbuff, fmt, num_open.rlim_max);
+      fprintf(stderr, "shrinking array for %s file descriptors\n", strbuff);
+
+      tmpfd = realloc(fd, sizeof(*fd) * (size_t)(num_open.rlim_max));
+      if (!tmpfd) {
+        sprintf(strbuff, "fd, realloc() failed, "
+                "errno %d, %s", our_errno(), strerror(our_errno()));
+        fprintf(stderr, "%s\n", strbuff);
+      }
+      else {
+        fd = tmpfd;
+        tmpfd = NULL;
+      }
+
+    }
+
+  }
+
+  sprintf(strbuff, fmt, num_open.rlim_max);
+  fprintf(stderr, "%s file descriptors open\n", strbuff);
+
+  /* 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;
+  }
+
+  if ((curl = curl_easy_init()) == NULL) {
+    fprintf(stderr, "curl_easy_init() failed\n");
+    close_file_descriptors();
+    curl_global_cleanup();
+    return TEST_ERR_MAJOR_BAD;
+  }
+
+  curl_easy_setopt(curl, CURLOPT_URL, URL);
+  curl_easy_setopt(curl, CURLOPT_HEADER, TRUE);
+
+  res = curl_easy_perform(curl);
+
+  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) */