text: // SPDX-License-Identifier: GPL-2.0
  #include <api/fd/array.h>
  #include <poll.h>
  #include "util/debug.h"
  #include "tests/tests.h"
  
  static void fdarray__init_revents(struct fdarray *fda, short revents)
  {
  	int fd;
  
  	fda->nr = fda->nr_alloc;
  
  	for (fd = 0; fd < fda->nr; ++fd) {
  		fda->entries[fd].fd	 = fda->nr - fd;
  		fda->entries[fd].revents = revents;
  	}
  }
  
  static int fdarray__fprintf_prefix(struct fdarray *fda, const char *prefix, FILE *fp)
  {
  	int printed = 0;
  
  	if (verbose <= 0)
  		return 0;
  
  	printed += fprintf(fp, "\n%s: ", prefix);
  	return printed + fdarray__fprintf(fda, fp);
  }
  
  int test__fdarray__filter(struct test *test __maybe_unused, int subtest __maybe_unused)
  {
  	int nr_fds, expected_fd[2], fd, err = TEST_FAIL;
  	struct fdarray *fda = fdarray__new(5, 5);
  
  	if (fda == NULL) {
  		pr_debug("\nfdarray__new() failed!");
  		goto out;
  	}
  
  	fdarray__init_revents(fda, POLLIN);
  	nr_fds = fdarray__filter(fda, POLLHUP, NULL, NULL);
  	if (nr_fds != fda->nr_alloc) {
  		pr_debug("\nfdarray__filter()=%d != %d shouldn't have filtered anything",
  			 nr_fds, fda->nr_alloc);
  		goto out_delete;
  	}
  
  	fdarray__init_revents(fda, POLLHUP);
  	nr_fds = fdarray__filter(fda, POLLHUP, NULL, NULL);
  	if (nr_fds != 0) {
  		pr_debug("\nfdarray__filter()=%d != %d, should have filtered all fds",
  			 nr_fds, fda->nr_alloc);
  		goto out_delete;
  	}
  
  	fdarray__init_revents(fda, POLLHUP);
  	fda->entries[2].revents = POLLIN;
  	expected_fd[0] = fda->entries[2].fd;
  
  	pr_debug("\nfiltering all but fda->entries[2]:");
  	fdarray__fprintf_prefix(fda, "before", stderr);
  	nr_fds = fdarray__filter(fda, POLLHUP, NULL, NULL);
  	fdarray__fprintf_prefix(fda, " after", stderr);
  	if (nr_fds != 1) {
  		pr_debug("\nfdarray__filter()=%d != 1, should have left just one event", nr_fds);
  		goto out_delete;
  	}
  
  	if (fda->entries[0].fd != expected_fd[0]) {
  		pr_debug("\nfda->entries[0].fd=%d != %d\n",
  			 fda->entries[0].fd, expected_fd[0]);
  		goto out_delete;
  	}
  
  	fdarray__init_revents(fda, POLLHUP);
  	fda->entries[0].revents = POLLIN;
  	expected_fd[0] = fda->entries[0].fd;
  	fda->entries[3].revents = POLLIN;
  	expected_fd[1] = fda->entries[3].fd;
  
  	pr_debug("\nfiltering all but (fda->entries[0], fda->entries[3]):");
  	fdarray__fprintf_prefix(fda, "before", stderr);
  	nr_fds = fdarray__filter(fda, POLLHUP, NULL, NULL);
  	fdarray__fprintf_prefix(fda, " after", stderr);
  	if (nr_fds != 2) {
  		pr_debug("\nfdarray__filter()=%d != 2, should have left just two events",
  			 nr_fds);
  		goto out_delete;
  	}
  
  	for (fd = 0; fd < 2; ++fd) {
  		if (fda->entries[fd].fd != expected_fd[fd]) {
  			pr_debug("\nfda->entries[%d].fd=%d != %d\n", fd,
  				 fda->entries[fd].fd, expected_fd[fd]);
  			goto out_delete;
  		}
  	}
  
  	pr_debug("\n");
  
  	err = 0;
  out_delete:
  	fdarray__delete(fda);
  out:
  	return err;
  }
  
  int test__fdarray__add(struct test *test __maybe_unused, int subtest __maybe_unused)
  {
  	int err = TEST_FAIL;
  	struct fdarray *fda = fdarray__new(2, 2);
  
  	if (fda == NULL) {
  		pr_debug("\nfdarray__new() failed!");
  		goto out;
  	}
  
  #define FDA_CHECK(_idx, _fd, _revents)					   \
  	if (fda->entries[_idx].fd != _fd) {				   \
  		pr_debug("\n%d: fda->entries[%d](%d) != %d!",		   \
  			 __LINE__, _idx, fda->entries[1].fd, _fd);	   \
  		goto out_delete;					   \
  	}								   \
  	if (fda->entries[_idx].events != (_revents)) {			   \
  		pr_debug("\n%d: fda->entries[%d].revents(%d) != %d!",	   \
  			 __LINE__, _idx, fda->entries[_idx].fd, _revents); \
  		goto out_delete;					   \
  	}
  
  #define FDA_ADD(_idx, _fd, _revents, _nr)				   \
  	if (fdarray__add(fda, _fd, _revents) < 0) {			   \
  		pr_debug("\n%d: fdarray__add(fda, %d, %d) failed!",	   \
  			 __LINE__,_fd, _revents);			   \
  		goto out_delete;					   \
  	}								   \
  	if (fda->nr != _nr) {						   \
  		pr_debug("\n%d: fdarray__add(fda, %d, %d)=%d != %d",	   \
  			 __LINE__,_fd, _revents, fda->nr, _nr);		   \
  		goto out_delete;					   \
  	}								   \
  	FDA_CHECK(_idx, _fd, _revents)
  
  	FDA_ADD(0, 1, POLLIN, 1);
  	FDA_ADD(1, 2, POLLERR, 2);
  
  	fdarray__fprintf_prefix(fda, "before growing array", stderr);
  
  	FDA_ADD(2, 35, POLLHUP, 3);
  
  	if (fda->entries == NULL) {
  		pr_debug("\nfdarray__add(fda, 35, POLLHUP) should have allocated fda->pollfd!");
  		goto out_delete;
  	}
  
  	fdarray__fprintf_prefix(fda, "after 3rd add", stderr);
  
  	FDA_ADD(3, 88, POLLIN | POLLOUT, 4);
  
  	fdarray__fprintf_prefix(fda, "after 4th add", stderr);
  
  	FDA_CHECK(0, 1, POLLIN);
  	FDA_CHECK(1, 2, POLLERR);
  	FDA_CHECK(2, 35, POLLHUP);
  	FDA_CHECK(3, 88, POLLIN | POLLOUT);
  
  #undef FDA_ADD
  #undef FDA_CHECK
  
  	pr_debug("\n");
  
  	err = 0;
  out_delete:
  	fdarray__delete(fda);
  out:
  	return err;
  }
  