/*-
 * Copyright (c) 2011 Jilles Tjoelker
 * 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.
 */

/*
 * Test program for posix_spawn() and posix_spawnp() as specified by
 * IEEE Std. 1003.1-2008.
 */

#include <sys/param.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <dlfcn.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <spawn.h>

#include <atf-c.h>

static const char true_script[] =
    "#!/usr/bin/env\n"
    "/usr/bin/true\n";

char *myenv[2] = { "answer=42", NULL };

ATF_TC_WITHOUT_HEAD(posix_spawn_simple_test);
ATF_TC_BODY(posix_spawn_simple_test, tc)
{
        char *myargs[4];
        int error, status;
        pid_t pid, waitres;

        /* Make sure we have no child processes. */
        while (waitpid(-1, NULL, 0) != -1)
                ;
        ATF_REQUIRE_MSG(errno == ECHILD, "errno was not ECHILD: %d", errno);

        /* Simple test. */
        myargs[0] = "sh";
        myargs[1] = "-c";
        myargs[2] = "exit $answer";
        myargs[3] = NULL;
        error = posix_spawnp(&pid, myargs[0], NULL, NULL, myargs, myenv);
        ATF_REQUIRE(error == 0);
        waitres = waitpid(pid, &status, 0);
        ATF_REQUIRE(waitres == pid);
        ATF_REQUIRE(WIFEXITED(status) && WEXITSTATUS(status) == 42);
}

ATF_TC_WITHOUT_HEAD(posix_spawn_no_such_command_negative_test);
ATF_TC_BODY(posix_spawn_no_such_command_negative_test, tc)
{
        char *myargs[4];
        int error, status;
        pid_t pid, waitres;

        /*
         * If the executable does not exist, the function shall either fail
         * and not create a child process or succeed and create a child
         * process that exits with status 127.
         */
        myargs[0] = "/var/empty/nonexistent";
        myargs[1] = NULL;
        error = posix_spawn(&pid, myargs[0], NULL, NULL, myargs, myenv);
        if (error == 0) {
                waitres = waitpid(pid, &status, 0);
                ATF_REQUIRE(waitres == pid);
                ATF_REQUIRE(WIFEXITED(status) && WEXITSTATUS(status) == 127);
        } else {
                ATF_REQUIRE(error == ENOENT);
                waitres = waitpid(-1, NULL, 0);
                ATF_REQUIRE(waitres == -1 && errno == ECHILD);
        }
}

ATF_TC_WITHOUT_HEAD(posix_spawnp_enoexec_fallback);
ATF_TC_BODY(posix_spawnp_enoexec_fallback, tc)
{
        char buf[FILENAME_MAX];
        char *myargs[2];
        int error, status;
        pid_t pid, waitres;

        snprintf(buf, sizeof(buf), "%s/spawnp_enoexec.sh",
            atf_tc_get_config_var(tc, "srcdir"));
        myargs[0] = buf;
        myargs[1] = NULL;
        error = posix_spawnp(&pid, myargs[0], NULL, NULL, myargs, myenv);
        ATF_REQUIRE(error == 0);
        waitres = waitpid(pid, &status, 0);
        ATF_REQUIRE(waitres == pid);
        ATF_REQUIRE(WIFEXITED(status) && WEXITSTATUS(status) == 42);
}

ATF_TC_WITHOUT_HEAD(posix_spawnp_enoexec_fallback_null_argv0);
ATF_TC_BODY(posix_spawnp_enoexec_fallback_null_argv0, tc)
{
        char buf[FILENAME_MAX];
        char *myargs[1];
        int error;
        pid_t pid;

        snprintf(buf, sizeof(buf), "%s/spawnp_enoexec.sh",
            atf_tc_get_config_var(tc, "srcdir"));
        myargs[0] = NULL;
        error = posix_spawnp(&pid, buf, NULL, NULL, myargs, myenv);
        ATF_REQUIRE(error == EINVAL);
}

ATF_TC(posix_spawnp_eacces);
ATF_TC_HEAD(posix_spawnp_eacces, tc)
{
        atf_tc_set_md_var(tc, "descr", "Verify EACCES behavior in posix_spawnp");
        atf_tc_set_md_var(tc, "require.user", "unprivileged");
}
ATF_TC_BODY(posix_spawnp_eacces, tc)
{
        const struct spawnp_eacces_tc {
                const char      *pathvar;
                int              error_expected;
        } spawnp_eacces_tests[] = {
                { ".",                  EACCES }, /* File exists, but not +x */
                { "unsearchable",       ENOENT }, /* File exists, dir not +x */
        };
        char *myargs[2] = { "eacces", NULL };
        int error;

        error = mkdir("unsearchable", 0755);
        ATF_REQUIRE(error == 0);
        error = symlink("/usr/bin/true", "unsearchable/eacces");
        ATF_REQUIRE(error == 0);

        (void)chmod("unsearchable", 0444);

        /* this will create a non-executable file */
        atf_utils_create_file("eacces", true_script);

        for (size_t i = 0; i < nitems(spawnp_eacces_tests); i++) {
                const struct spawnp_eacces_tc *tc = &spawnp_eacces_tests[i];
                pid_t pid;

                error = setenv("PATH", tc->pathvar, 1);
                ATF_REQUIRE_EQ(0, error);

                error = posix_spawnp(&pid, myargs[0], NULL, NULL, myargs,
                    myenv);
                ATF_CHECK_INTEQ_MSG(tc->error_expected, error,
                    "path '%s'", tc->pathvar);
        }
}

#define NUM_DSO 512
ATF_TC_WITHOUT_HEAD(posix_spawnp_stackunderflow);
ATF_TC_BODY(posix_spawnp_stackunderflow, tc)
{
        struct stat sb;
        char dsopath[MAXPATHLEN];
        char *myargs[] = { "true", NULL };
        void **handles;
        char *dsomap;
        size_t dsosz;
        int error, fd, nfd, status;
        pid_t pid, waitres;

        /* Make sure we have no child processes. */
        while (waitpid(-1, NULL, 0) != -1)
                ;
        ATF_REQUIRE_MSG(errno == ECHILD, "errno was not ECHILD: %d", errno);

        (void)snprintf(dsopath, sizeof(dsopath), "%s/libdummy.so",
            atf_tc_get_config_var(tc, "srcdir"));

        fd = open(dsopath, O_RDONLY);
        ATF_REQUIRE(fd >= 0);

        /*
         * We'll open our original shlib and fdlopen() it repeatedly until we
         * have a lot of DSOs open, then we'll trigger a posix_spawnp.  This
         * previously unearthed suboptimal stack usage in rtld that caused
         * posix_spawnp()'s effectively-vforked environment to underflow its
         * stack.
         *
         * We only get one shot to trigger the underflow, as rtld binding the
         * symbols in the exec path in the rfork-child will affect the main
         * process, so we only test that we don't have a problem with a large
         * number of DSOs loaded.
         */
        ATF_REQUIRE(fstat(fd, &sb) == 0);
        dsosz = sb.st_size;
        dsomap = mmap(NULL, dsosz, PROT_READ, MAP_SHARED, fd, 0);
        ATF_REQUIRE(dsomap != MAP_FAILED);

        handles = calloc(sizeof(*handles), NUM_DSO);
        ATF_REQUIRE(handles != NULL);

        for (int i = 0; i < NUM_DSO; i++) {
                nfd = memfd_create("dsobase", MFD_CLOEXEC);
                ATF_REQUIRE(nfd >= 0);
                ATF_REQUIRE(ftruncate(nfd, dsosz) == 0);
                ATF_REQUIRE(write(nfd, dsomap, dsosz) == dsosz);

                handles[i] = fdlopen(nfd, RTLD_LAZY);
                ATF_REQUIRE(handles[i] != NULL);
                if (i > 0)
                        ATF_REQUIRE(handles[i] != handles[i - 1]);

                close(nfd);
        }

        error = posix_spawnp(&pid, myargs[0], NULL, NULL, myargs, myenv);
        ATF_REQUIRE(error == 0);
        waitres = waitpid(pid, &status, 0);
        ATF_REQUIRE(waitres == pid);
        ATF_REQUIRE(WIFEXITED(status) && WEXITSTATUS(status) == 0);
}

ATF_TP_ADD_TCS(tp)
{

        ATF_TP_ADD_TC(tp, posix_spawn_simple_test);
        ATF_TP_ADD_TC(tp, posix_spawn_no_such_command_negative_test);
        ATF_TP_ADD_TC(tp, posix_spawnp_enoexec_fallback);
        ATF_TP_ADD_TC(tp, posix_spawnp_enoexec_fallback_null_argv0);
        ATF_TP_ADD_TC(tp, posix_spawnp_eacces);
        ATF_TP_ADD_TC(tp, posix_spawnp_stackunderflow);

        return (atf_no_error());
}