// SPDX-License-Identifier: GPL-2.0-only
/*
 * vsock test utilities
 *
 * Copyright (C) 2017 Red Hat, Inc.
 *
 * Author: Stefan Hajnoczi <stefanha@redhat.com>
 */

#include <errno.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
#include <assert.h>
#include <sys/epoll.h>

#include "timeout.h"
#include "control.h"
#include "util.h"

/* Install signal handlers */
void init_signals(void)
{
        struct sigaction act = {
                .sa_handler = sigalrm,
        };

        sigaction(SIGALRM, &act, NULL);
        signal(SIGPIPE, SIG_IGN);
}

/* Parse a CID in string representation */
unsigned int parse_cid(const char *str)
{
        char *endptr = NULL;
        unsigned long n;

        errno = 0;
        n = strtoul(str, &endptr, 10);
        if (errno || *endptr != '\0') {
                fprintf(stderr, "malformed CID \"%s\"\n", str);
                exit(EXIT_FAILURE);
        }
        return n;
}

/* Wait for the remote to close the connection */
void vsock_wait_remote_close(int fd)
{
        struct epoll_event ev;
        int epollfd, nfds;

        epollfd = epoll_create1(0);
        if (epollfd == -1) {
                perror("epoll_create1");
                exit(EXIT_FAILURE);
        }

        ev.events = EPOLLRDHUP | EPOLLHUP;
        ev.data.fd = fd;
        if (epoll_ctl(epollfd, EPOLL_CTL_ADD, fd, &ev) == -1) {
                perror("epoll_ctl");
                exit(EXIT_FAILURE);
        }

        nfds = epoll_wait(epollfd, &ev, 1, TIMEOUT * 1000);
        if (nfds == -1) {
                perror("epoll_wait");
                exit(EXIT_FAILURE);
        }

        if (nfds == 0) {
                fprintf(stderr, "epoll_wait timed out\n");
                exit(EXIT_FAILURE);
        }

        assert(nfds == 1);
        assert(ev.events & (EPOLLRDHUP | EPOLLHUP));
        assert(ev.data.fd == fd);

        close(epollfd);
}

/* Connect to <cid, port> and return the file descriptor. */
static int vsock_connect(unsigned int cid, unsigned int port, int type)
{
        union {
                struct sockaddr sa;
                struct sockaddr_vm svm;
        } addr = {
                .svm = {
                        .svm_family = AF_VSOCK,
                        .svm_port = port,
                        .svm_cid = cid,
                },
        };
        int ret;
        int fd;

        control_expectln("LISTENING");

        fd = socket(AF_VSOCK, type, 0);

        timeout_begin(TIMEOUT);
        do {
                ret = connect(fd, &addr.sa, sizeof(addr.svm));
                timeout_check("connect");
        } while (ret < 0 && errno == EINTR);
        timeout_end();

        if (ret < 0) {
                int old_errno = errno;

                close(fd);
                fd = -1;
                errno = old_errno;
        }
        return fd;
}

int vsock_stream_connect(unsigned int cid, unsigned int port)
{
        return vsock_connect(cid, port, SOCK_STREAM);
}

int vsock_seqpacket_connect(unsigned int cid, unsigned int port)
{
        return vsock_connect(cid, port, SOCK_SEQPACKET);
}

/* Listen on <cid, port> and return the first incoming connection.  The remote
 * address is stored to clientaddrp.  clientaddrp may be NULL.
 */
static int vsock_accept(unsigned int cid, unsigned int port,
                        struct sockaddr_vm *clientaddrp, int type)
{
        union {
                struct sockaddr sa;
                struct sockaddr_vm svm;
        } addr = {
                .svm = {
                        .svm_family = AF_VSOCK,
                        .svm_port = port,
                        .svm_cid = cid,
                },
        };
        union {
                struct sockaddr sa;
                struct sockaddr_vm svm;
        } clientaddr;
        socklen_t clientaddr_len = sizeof(clientaddr.svm);
        int fd;
        int client_fd;
        int old_errno;

        fd = socket(AF_VSOCK, type, 0);

        if (bind(fd, &addr.sa, sizeof(addr.svm)) < 0) {
                perror("bind");
                exit(EXIT_FAILURE);
        }

        if (listen(fd, 1) < 0) {
                perror("listen");
                exit(EXIT_FAILURE);
        }

        control_writeln("LISTENING");

        timeout_begin(TIMEOUT);
        do {
                client_fd = accept(fd, &clientaddr.sa, &clientaddr_len);
                timeout_check("accept");
        } while (client_fd < 0 && errno == EINTR);
        timeout_end();

        old_errno = errno;
        close(fd);
        errno = old_errno;

        if (client_fd < 0)
                return client_fd;

        if (clientaddr_len != sizeof(clientaddr.svm)) {
                fprintf(stderr, "unexpected addrlen from accept(2), %zu\n",
                        (size_t)clientaddr_len);
                exit(EXIT_FAILURE);
        }
        if (clientaddr.sa.sa_family != AF_VSOCK) {
                fprintf(stderr, "expected AF_VSOCK from accept(2), got %d\n",
                        clientaddr.sa.sa_family);
                exit(EXIT_FAILURE);
        }

        if (clientaddrp)
                *clientaddrp = clientaddr.svm;
        return client_fd;
}

int vsock_stream_accept(unsigned int cid, unsigned int port,
                        struct sockaddr_vm *clientaddrp)
{
        return vsock_accept(cid, port, clientaddrp, SOCK_STREAM);
}

int vsock_seqpacket_accept(unsigned int cid, unsigned int port,
                           struct sockaddr_vm *clientaddrp)
{
        return vsock_accept(cid, port, clientaddrp, SOCK_SEQPACKET);
}

/* Transmit one byte and check the return value.
 *
 * expected_ret:
 *  <0 Negative errno (for testing errors)
 *   0 End-of-file
 *   1 Success
 */
void send_byte(int fd, int expected_ret, int flags)
{
        const uint8_t byte = 'A';
        ssize_t nwritten;

        timeout_begin(TIMEOUT);
        do {
                nwritten = send(fd, &byte, sizeof(byte), flags);
                timeout_check("write");
        } while (nwritten < 0 && errno == EINTR);
        timeout_end();

        if (expected_ret < 0) {
                if (nwritten != -1) {
                        fprintf(stderr, "bogus send(2) return value %zd\n",
                                nwritten);
                        exit(EXIT_FAILURE);
                }
                if (errno != -expected_ret) {
                        perror("write");
                        exit(EXIT_FAILURE);
                }
                return;
        }

        if (nwritten < 0) {
                perror("write");
                exit(EXIT_FAILURE);
        }
        if (nwritten == 0) {
                if (expected_ret == 0)
                        return;

                fprintf(stderr, "unexpected EOF while sending byte\n");
                exit(EXIT_FAILURE);
        }
        if (nwritten != sizeof(byte)) {
                fprintf(stderr, "bogus send(2) return value %zd\n", nwritten);
                exit(EXIT_FAILURE);
        }
}

/* Receive one byte and check the return value.
 *
 * expected_ret:
 *  <0 Negative errno (for testing errors)
 *   0 End-of-file
 *   1 Success
 */
void recv_byte(int fd, int expected_ret, int flags)
{
        uint8_t byte;
        ssize_t nread;

        timeout_begin(TIMEOUT);
        do {
                nread = recv(fd, &byte, sizeof(byte), flags);
                timeout_check("read");
        } while (nread < 0 && errno == EINTR);
        timeout_end();

        if (expected_ret < 0) {
                if (nread != -1) {
                        fprintf(stderr, "bogus recv(2) return value %zd\n",
                                nread);
                        exit(EXIT_FAILURE);
                }
                if (errno != -expected_ret) {
                        perror("read");
                        exit(EXIT_FAILURE);
                }
                return;
        }

        if (nread < 0) {
                perror("read");
                exit(EXIT_FAILURE);
        }
        if (nread == 0) {
                if (expected_ret == 0)
                        return;

                fprintf(stderr, "unexpected EOF while receiving byte\n");
                exit(EXIT_FAILURE);
        }
        if (nread != sizeof(byte)) {
                fprintf(stderr, "bogus recv(2) return value %zd\n", nread);
                exit(EXIT_FAILURE);
        }
        if (byte != 'A') {
                fprintf(stderr, "unexpected byte read %c\n", byte);
                exit(EXIT_FAILURE);
        }
}

/* Run test cases.  The program terminates if a failure occurs. */
void run_tests(const struct test_case *test_cases,
               const struct test_opts *opts)
{
        int i;

        for (i = 0; test_cases[i].name; i++) {
                void (*run)(const struct test_opts *opts);
                char *line;

                printf("%d - %s...", i, test_cases[i].name);
                fflush(stdout);

                /* Full barrier before executing the next test.  This
                 * ensures that client and server are executing the
                 * same test case.  In particular, it means whoever is
                 * faster will not see the peer still executing the
                 * last test.  This is important because port numbers
                 * can be used by multiple test cases.
                 */
                if (test_cases[i].skip)
                        control_writeln("SKIP");
                else
                        control_writeln("NEXT");

                line = control_readln();
                if (control_cmpln(line, "SKIP", false) || test_cases[i].skip) {

                        printf("skipped\n");

                        free(line);
                        continue;
                }

                control_cmpln(line, "NEXT", true);
                free(line);

                if (opts->mode == TEST_MODE_CLIENT)
                        run = test_cases[i].run_client;
                else
                        run = test_cases[i].run_server;

                if (run)
                        run(opts);

                printf("ok\n");
        }
}

void list_tests(const struct test_case *test_cases)
{
        int i;

        printf("ID\tTest name\n");

        for (i = 0; test_cases[i].name; i++)
                printf("%d\t%s\n", i, test_cases[i].name);

        exit(EXIT_FAILURE);
}

void skip_test(struct test_case *test_cases, size_t test_cases_len,
               const char *test_id_str)
{
        unsigned long test_id;
        char *endptr = NULL;

        errno = 0;
        test_id = strtoul(test_id_str, &endptr, 10);
        if (errno || *endptr != '\0') {
                fprintf(stderr, "malformed test ID \"%s\"\n", test_id_str);
                exit(EXIT_FAILURE);
        }

        if (test_id >= test_cases_len) {
                fprintf(stderr, "test ID (%lu) larger than the max allowed (%lu)\n",
                        test_id, test_cases_len - 1);
                exit(EXIT_FAILURE);
        }

        test_cases[test_id].skip = true;
}