tests: cache glibc version check

[git/gitster.git] / t / helper / test-simple-ipc.c

/*
 * test-simple-ipc.c: verify that the Inter-Process Communication works.
 */

#include "test-tool.h"
#include "cache.h"
#include "strbuf.h"
#include "simple-ipc.h"
#include "parse-options.h"
#include "thread-utils.h"
#include "strvec.h"
#include "run-command.h"

#ifndef SUPPORTS_SIMPLE_IPC
int cmd__simple_ipc(int argc, const char **argv)
{
        die("simple IPC not available on this platform");
}
#else

/*
 * The test daemon defines an "application callback" that supports a
 * series of commands (see `test_app_cb()`).
 *
 * Unknown commands are caught here and we send an error message back
 * to the client process.
 */
static int app__unhandled_command(const char *command,
                                  ipc_server_reply_cb *reply_cb,
                                  struct ipc_server_reply_data *reply_data)
{
        struct strbuf buf = STRBUF_INIT;
        int ret;

        strbuf_addf(&buf, "unhandled command: %s", command);
        ret = reply_cb(reply_data, buf.buf, buf.len);
        strbuf_release(&buf);

        return ret;
}

/*
 * Reply with a single very large buffer.  This is to ensure that
 * long response are properly handled -- whether the chunking occurs
 * in the kernel or in the (probably pkt-line) layer.
 */
#define BIG_ROWS (10000)
static int app__big_command(ipc_server_reply_cb *reply_cb,
                            struct ipc_server_reply_data *reply_data)
{
        struct strbuf buf = STRBUF_INIT;
        int row;
        int ret;

        for (row = 0; row < BIG_ROWS; row++)
                strbuf_addf(&buf, "big: %.75d\n", row);

        ret = reply_cb(reply_data, buf.buf, buf.len);
        strbuf_release(&buf);

        return ret;
}

/*
 * Reply with a series of lines.  This is to ensure that we can incrementally
 * compute the response and chunk it to the client.
 */
#define CHUNK_ROWS (10000)
static int app__chunk_command(ipc_server_reply_cb *reply_cb,
                              struct ipc_server_reply_data *reply_data)
{
        struct strbuf buf = STRBUF_INIT;
        int row;
        int ret;

        for (row = 0; row < CHUNK_ROWS; row++) {
                strbuf_setlen(&buf, 0);
                strbuf_addf(&buf, "big: %.75d\n", row);
                ret = reply_cb(reply_data, buf.buf, buf.len);
        }

        strbuf_release(&buf);

        return ret;
}

/*
 * Slowly reply with a series of lines.  This is to model an expensive to
 * compute chunked response (which might happen if this callback is running
 * in a thread and is fighting for a lock with other threads).
 */
#define SLOW_ROWS     (1000)
#define SLOW_DELAY_MS (10)
static int app__slow_command(ipc_server_reply_cb *reply_cb,
                             struct ipc_server_reply_data *reply_data)
{
        struct strbuf buf = STRBUF_INIT;
        int row;
        int ret;

        for (row = 0; row < SLOW_ROWS; row++) {
                strbuf_setlen(&buf, 0);
                strbuf_addf(&buf, "big: %.75d\n", row);
                ret = reply_cb(reply_data, buf.buf, buf.len);
                sleep_millisec(SLOW_DELAY_MS);
        }

        strbuf_release(&buf);

        return ret;
}

/*
 * The client sent a command followed by a (possibly very) large buffer.
 */
static int app__sendbytes_command(const char *received, size_t received_len,
                                  ipc_server_reply_cb *reply_cb,
                                  struct ipc_server_reply_data *reply_data)
{
        struct strbuf buf_resp = STRBUF_INIT;
        const char *p = "?";
        int len_ballast = 0;
        int k;
        int errs = 0;
        int ret;

        /*
         * The test is setup to send:
         *     "sendbytes" SP <n * char>
         */
        if (received_len < strlen("sendbytes "))
                BUG("received_len is short in app__sendbytes_command");

        if (skip_prefix(received, "sendbytes ", &p))
                len_ballast = strlen(p);

        /*
         * Verify that the ballast is n copies of a single letter.
         * And that the multi-threaded IO layer didn't cross the streams.
         */
        for (k = 1; k < len_ballast; k++)
                if (p[k] != p[0])
                        errs++;

        if (errs)
                strbuf_addf(&buf_resp, "errs:%d\n", errs);
        else
                strbuf_addf(&buf_resp, "rcvd:%c%08d\n", p[0], len_ballast);

        ret = reply_cb(reply_data, buf_resp.buf, buf_resp.len);

        strbuf_release(&buf_resp);

        return ret;
}

/*
 * An arbitrary fixed address to verify that the application instance
 * data is handled properly.
 */
static int my_app_data = 42;

static ipc_server_application_cb test_app_cb;

/*
 * This is the "application callback" that sits on top of the
 * "ipc-server".  It completely defines the set of commands supported
 * by this application.
 */
static int test_app_cb(void *application_data,
                       const char *command, size_t command_len,
                       ipc_server_reply_cb *reply_cb,
                       struct ipc_server_reply_data *reply_data)
{
        /*
         * Verify that we received the application-data that we passed
         * when we started the ipc-server.  (We have several layers of
         * callbacks calling callbacks and it's easy to get things mixed
         * up (especially when some are "void*").)
         */
        if (application_data != (void*)&my_app_data)
                BUG("application_cb: application_data pointer wrong");

        if (command_len == 4 && !strncmp(command, "quit", 4)) {
                /*
                 * The client sent a "quit" command.  This is an async
                 * request for the server to shutdown.
                 *
                 * We DO NOT send the client a response message
                 * (because we have nothing to say and the other
                 * server threads have not yet stopped).
                 *
                 * Tell the ipc-server layer to start shutting down.
                 * This includes: stop listening for new connections
                 * on the socket/pipe and telling all worker threads
                 * to finish/drain their outgoing responses to other
                 * clients.
                 *
                 * This DOES NOT force an immediate sync shutdown.
                 */
                return SIMPLE_IPC_QUIT;
        }

        if (command_len == 4 && !strncmp(command, "ping", 4)) {
                const char *answer = "pong";
                return reply_cb(reply_data, answer, strlen(answer));
        }

        if (command_len == 3 && !strncmp(command, "big", 3))
                return app__big_command(reply_cb, reply_data);

        if (command_len == 5 && !strncmp(command, "chunk", 5))
                return app__chunk_command(reply_cb, reply_data);

        if (command_len == 4 && !strncmp(command, "slow", 4))
                return app__slow_command(reply_cb, reply_data);

        if (command_len >= 10 && starts_with(command, "sendbytes "))
                return app__sendbytes_command(command, command_len,
                                              reply_cb, reply_data);

        return app__unhandled_command(command, reply_cb, reply_data);
}

struct cl_args
{
        const char *subcommand;
        const char *path;
        const char *token;

        int nr_threads;
        int max_wait_sec;
        int bytecount;
        int batchsize;

        char bytevalue;
};

static struct cl_args cl_args = {
        .subcommand = NULL,
        .path = "ipc-test",
        .token = NULL,

        .nr_threads = 5,
        .max_wait_sec = 60,
        .bytecount = 1024,
        .batchsize = 10,

        .bytevalue = 'x',
};

/*
 * This process will run as a simple-ipc server and listen for IPC commands
 * from client processes.
 */
static int daemon__run_server(void)
{
        int ret;

        struct ipc_server_opts opts = {
                .nr_threads = cl_args.nr_threads,
        };

        /*
         * Synchronously run the ipc-server.  We don't need any application
         * instance data, so pass an arbitrary pointer (that we'll later
         * verify made the round trip).
         */
        ret = ipc_server_run(cl_args.path, &opts, test_app_cb, (void*)&my_app_data);
        if (ret == -2)
                error("socket/pipe already in use: '%s'", cl_args.path);
        else if (ret == -1)
                error_errno("could not start server on: '%s'", cl_args.path);

        return ret;
}

static start_bg_wait_cb bg_wait_cb;

static int bg_wait_cb(const struct child_process *cp, void *cb_data)
{
        int s = ipc_get_active_state(cl_args.path);

        switch (s) {
        case IPC_STATE__LISTENING:
                /* child is "ready" */
                return 0;

        case IPC_STATE__NOT_LISTENING:
        case IPC_STATE__PATH_NOT_FOUND:
                /* give child more time */
                return 1;

        default:
        case IPC_STATE__INVALID_PATH:
        case IPC_STATE__OTHER_ERROR:
                /* all the time in world won't help */
                return -1;
        }
}

static int daemon__start_server(void)
{
        struct child_process cp = CHILD_PROCESS_INIT;
        enum start_bg_result sbgr;

        strvec_push(&cp.args, "test-tool");
        strvec_push(&cp.args, "simple-ipc");
        strvec_push(&cp.args, "run-daemon");
        strvec_pushf(&cp.args, "--name=%s", cl_args.path);
        strvec_pushf(&cp.args, "--threads=%d", cl_args.nr_threads);

        cp.no_stdin = 1;
        cp.no_stdout = 1;
        cp.no_stderr = 1;

        sbgr = start_bg_command(&cp, bg_wait_cb, NULL, cl_args.max_wait_sec);

        switch (sbgr) {
        case SBGR_READY:
                return 0;

        default:
        case SBGR_ERROR:
        case SBGR_CB_ERROR:
                return error("daemon failed to start");

        case SBGR_TIMEOUT:
                return error("daemon not online yet");

        case SBGR_DIED:
                return error("daemon terminated");
        }
}

/*
 * This process will run a quick probe to see if a simple-ipc server
 * is active on this path.
 *
 * Returns 0 if the server is alive.
 */
static int client__probe_server(void)
{
        enum ipc_active_state s;

        s = ipc_get_active_state(cl_args.path);
        switch (s) {
        case IPC_STATE__LISTENING:
                return 0;

        case IPC_STATE__NOT_LISTENING:
                return error("no server listening at '%s'", cl_args.path);

        case IPC_STATE__PATH_NOT_FOUND:
                return error("path not found '%s'", cl_args.path);

        case IPC_STATE__INVALID_PATH:
                return error("invalid pipe/socket name '%s'", cl_args.path);

        case IPC_STATE__OTHER_ERROR:
        default:
                return error("other error for '%s'", cl_args.path);
        }
}

/*
 * Send an IPC command token to an already-running server daemon and
 * print the response.
 *
 * This is a simple 1 word command/token that `test_app_cb()` (in the
 * daemon process) will understand.
 */
static int client__send_ipc(void)
{
        const char *command = "(no-command)";
        struct strbuf buf = STRBUF_INIT;
        struct ipc_client_connect_options options
                = IPC_CLIENT_CONNECT_OPTIONS_INIT;

        if (cl_args.token && *cl_args.token)
                command = cl_args.token;

        options.wait_if_busy = 1;
        options.wait_if_not_found = 0;

        if (!ipc_client_send_command(cl_args.path, &options,
                                     command, strlen(command),
                                     &buf)) {
                if (buf.len) {
                        printf("%s\n", buf.buf);
                        fflush(stdout);
                }
                strbuf_release(&buf);

                return 0;
        }

        return error("failed to send '%s' to '%s'", command, cl_args.path);
}

/*
 * Send an IPC command to an already-running server and ask it to
 * shutdown.  "send quit" is an async request and queues a shutdown
 * event in the server, so we spin and wait here for it to actually
 * shutdown to make the unit tests a little easier to write.
 */
static int client__stop_server(void)
{
        int ret;
        time_t time_limit, now;
        enum ipc_active_state s;

        time(&time_limit);
        time_limit += cl_args.max_wait_sec;

        cl_args.token = "quit";

        ret = client__send_ipc();
        if (ret)
                return ret;

        for (;;) {
                sleep_millisec(100);

                s = ipc_get_active_state(cl_args.path);

                if (s != IPC_STATE__LISTENING) {
                        /*
                         * The socket/pipe is gone and/or has stopped
                         * responding.  Lets assume that the daemon
                         * process has exited too.
                         */
                        return 0;
                }

                time(&now);
                if (now > time_limit)
                        return error("daemon has not shutdown yet");
        }
}

/*
 * Send an IPC command followed by ballast to confirm that a large
 * message can be sent and that the kernel or pkt-line layers will
 * properly chunk it and that the daemon receives the entire message.
 */
static int do_sendbytes(int bytecount, char byte, const char *path,
                        const struct ipc_client_connect_options *options)
{
        struct strbuf buf_send = STRBUF_INIT;
        struct strbuf buf_resp = STRBUF_INIT;

        strbuf_addstr(&buf_send, "sendbytes ");
        strbuf_addchars(&buf_send, byte, bytecount);

        if (!ipc_client_send_command(path, options,
                                     buf_send.buf, buf_send.len,
                                     &buf_resp)) {
                strbuf_rtrim(&buf_resp);
                printf("sent:%c%08d %s\n", byte, bytecount, buf_resp.buf);
                fflush(stdout);
                strbuf_release(&buf_send);
                strbuf_release(&buf_resp);

                return 0;
        }

        return error("client failed to sendbytes(%d, '%c') to '%s'",
                     bytecount, byte, path);
}

/*
 * Send an IPC command with ballast to an already-running server daemon.
 */
static int client__sendbytes(void)
{
        struct ipc_client_connect_options options
                = IPC_CLIENT_CONNECT_OPTIONS_INIT;

        options.wait_if_busy = 1;
        options.wait_if_not_found = 0;
        options.uds_disallow_chdir = 0;

        return do_sendbytes(cl_args.bytecount, cl_args.bytevalue, cl_args.path,
                            &options);
}

struct multiple_thread_data {
        pthread_t pthread_id;
        struct multiple_thread_data *next;
        const char *path;
        int bytecount;
        int batchsize;
        int sum_errors;
        int sum_good;
        char letter;
};

static void *multiple_thread_proc(void *_multiple_thread_data)
{
        struct multiple_thread_data *d = _multiple_thread_data;
        int k;
        struct ipc_client_connect_options options
                = IPC_CLIENT_CONNECT_OPTIONS_INIT;

        options.wait_if_busy = 1;
        options.wait_if_not_found = 0;
        /*
         * A multi-threaded client should not be randomly calling chdir().
         * The test will pass without this restriction because the test is
         * not otherwise accessing the filesystem, but it makes us honest.
         */
        options.uds_disallow_chdir = 1;

        trace2_thread_start("multiple");

        for (k = 0; k < d->batchsize; k++) {
                if (do_sendbytes(d->bytecount + k, d->letter, d->path, &options))
                        d->sum_errors++;
                else
                        d->sum_good++;
        }

        trace2_thread_exit();
        return NULL;
}

/*
 * Start a client-side thread pool.  Each thread sends a series of
 * IPC requests.  Each request is on a new connection to the server.
 */
static int client__multiple(void)
{
        struct multiple_thread_data *list = NULL;
        int k;
        int sum_join_errors = 0;
        int sum_thread_errors = 0;
        int sum_good = 0;

        for (k = 0; k < cl_args.nr_threads; k++) {
                struct multiple_thread_data *d = xcalloc(1, sizeof(*d));
                d->next = list;
                d->path = cl_args.path;
                d->bytecount = cl_args.bytecount + cl_args.batchsize*(k/26);
                d->batchsize = cl_args.batchsize;
                d->sum_errors = 0;
                d->sum_good = 0;
                d->letter = 'A' + (k % 26);

                if (pthread_create(&d->pthread_id, NULL, multiple_thread_proc, d)) {
                        warning("failed to create thread[%d] skipping remainder", k);
                        free(d);
                        break;
                }

                list = d;
        }

        while (list) {
                struct multiple_thread_data *d = list;

                if (pthread_join(d->pthread_id, NULL))
                        sum_join_errors++;

                sum_thread_errors += d->sum_errors;
                sum_good += d->sum_good;

                list = d->next;
                free(d);
        }

        printf("client (good %d) (join %d), (errors %d)\n",
               sum_good, sum_join_errors, sum_thread_errors);

        return (sum_join_errors + sum_thread_errors) ? 1 : 0;
}

int cmd__simple_ipc(int argc, const char **argv)
{
        const char * const simple_ipc_usage[] = {
                N_("test-helper simple-ipc is-active    [<name>] [<options>]"),
                N_("test-helper simple-ipc run-daemon   [<name>] [<threads>]"),
                N_("test-helper simple-ipc start-daemon [<name>] [<threads>] [<max-wait>]"),
                N_("test-helper simple-ipc stop-daemon  [<name>] [<max-wait>]"),
                N_("test-helper simple-ipc send         [<name>] [<token>]"),
                N_("test-helper simple-ipc sendbytes    [<name>] [<bytecount>] [<byte>]"),
                N_("test-helper simple-ipc multiple     [<name>] [<threads>] [<bytecount>] [<batchsize>]"),
                NULL
        };

        const char *bytevalue = NULL;

        struct option options[] = {
#ifndef GIT_WINDOWS_NATIVE
                OPT_STRING(0, "name", &cl_args.path, N_("name"), N_("name or pathname of unix domain socket")),
#else
                OPT_STRING(0, "name", &cl_args.path, N_("name"), N_("named-pipe name")),
#endif
                OPT_INTEGER(0, "threads", &cl_args.nr_threads, N_("number of threads in server thread pool")),
                OPT_INTEGER(0, "max-wait", &cl_args.max_wait_sec, N_("seconds to wait for daemon to start or stop")),

                OPT_INTEGER(0, "bytecount", &cl_args.bytecount, N_("number of bytes")),
                OPT_INTEGER(0, "batchsize", &cl_args.batchsize, N_("number of requests per thread")),

                OPT_STRING(0, "byte", &bytevalue, N_("byte"), N_("ballast character")),
                OPT_STRING(0, "token", &cl_args.token, N_("token"), N_("command token to send to the server")),

                OPT_END()
        };

        if (argc < 2)
                usage_with_options(simple_ipc_usage, options);

        if (argc == 2 && !strcmp(argv[1], "-h"))
                usage_with_options(simple_ipc_usage, options);

        if (argc == 2 && !strcmp(argv[1], "SUPPORTS_SIMPLE_IPC"))
                return 0;

        cl_args.subcommand = argv[1];

        argc--;
        argv++;

        argc = parse_options(argc, argv, NULL, options, simple_ipc_usage, 0);

        if (cl_args.nr_threads < 1)
                cl_args.nr_threads = 1;
        if (cl_args.max_wait_sec < 0)
                cl_args.max_wait_sec = 0;
        if (cl_args.bytecount < 1)
                cl_args.bytecount = 1;
        if (cl_args.batchsize < 1)
                cl_args.batchsize = 1;

        if (bytevalue && *bytevalue)
                cl_args.bytevalue = bytevalue[0];

        /*
         * Use '!!' on all dispatch functions to map from `error()` style
         * (returns -1) style to `test_must_fail` style (expects 1).  This
         * makes shell error messages less confusing.
         */

        if (!strcmp(cl_args.subcommand, "is-active"))
                return !!client__probe_server();

        if (!strcmp(cl_args.subcommand, "run-daemon"))
                return !!daemon__run_server();

        if (!strcmp(cl_args.subcommand, "start-daemon"))
                return !!daemon__start_server();

        /*
         * Client commands follow.  Ensure a server is running before
         * sending any data.  This might be overkill, but then again
         * this is a test harness.
         */

        if (!strcmp(cl_args.subcommand, "stop-daemon")) {
                if (client__probe_server())
                        return 1;
                return !!client__stop_server();
        }

        if (!strcmp(cl_args.subcommand, "send")) {
                if (client__probe_server())
                        return 1;
                return !!client__send_ipc();
        }

        if (!strcmp(cl_args.subcommand, "sendbytes")) {
                if (client__probe_server())
                        return 1;
                return !!client__sendbytes();
        }

        if (!strcmp(cl_args.subcommand, "multiple")) {
                if (client__probe_server())
                        return 1;
                return !!client__multiple();
        }

        die("Unhandled subcommand: '%s'", cl_args.subcommand);
}
#endif