/*
 * builtin-inject.c
 *
 * Builtin inject command: Examine the live mode (stdin) event stream
 * and repipe it to stdout while optionally injecting additional
 * events into it.
 */
#include "builtin.h"

#include "perf.h"
#include "util/session.h"
#include "util/debug.h"

#include "util/parse-options.h"

static char             const *input_name = "-";
static bool             inject_build_ids;

static int event__repipe_synth(event_t *event,
                               struct perf_session *session __used)
{
        uint32_t size;
        void *buf = event;

        size = event->header.size;

        while (size) {
                int ret = write(STDOUT_FILENO, buf, size);
                if (ret < 0)
                        return -errno;

                size -= ret;
                buf += ret;
        }

        return 0;
}

static int event__repipe(event_t *event, struct sample_data *sample __used,
                         struct perf_session *session)
{
        return event__repipe_synth(event, session);
}

static int event__repipe_mmap(event_t *self, struct sample_data *sample,
                              struct perf_session *session)
{
        int err;

        err = event__process_mmap(self, sample, session);
        event__repipe(self, sample, session);

        return err;
}

static int event__repipe_task(event_t *self, struct sample_data *sample,
                              struct perf_session *session)
{
        int err;

        err = event__process_task(self, sample, session);
        event__repipe(self, sample, session);

        return err;
}

static int event__repipe_tracing_data(event_t *self,
                                      struct perf_session *session)
{
        int err;

        event__repipe_synth(self, session);
        err = event__process_tracing_data(self, session);

        return err;
}

static int dso__read_build_id(struct dso *self)
{
        if (self->has_build_id)
                return 0;

        if (filename__read_build_id(self->long_name, self->build_id,
                                    sizeof(self->build_id)) > 0) {
                self->has_build_id = true;
                return 0;
        }

        return -1;
}

static int dso__inject_build_id(struct dso *self, struct perf_session *session)
{
        u16 misc = PERF_RECORD_MISC_USER;
        struct machine *machine;
        int err;

        if (dso__read_build_id(self) < 0) {
                pr_debug("no build_id found for %s\n", self->long_name);
                return -1;
        }

        machine = perf_session__find_host_machine(session);
        if (machine == NULL) {
                pr_err("Can't find machine for session\n");
                return -1;
        }

        if (self->kernel)
                misc = PERF_RECORD_MISC_KERNEL;

        err = event__synthesize_build_id(self, misc, event__repipe,
                                         machine, session);
        if (err) {
                pr_err("Can't synthesize build_id event for %s\n", self->long_name);
                return -1;
        }

        return 0;
}

static int event__inject_buildid(event_t *event, struct sample_data *sample,
                                 struct perf_session *session)
{
        struct addr_location al;
        struct thread *thread;
        u8 cpumode;

        cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;

        thread = perf_session__findnew(session, event->ip.pid);
        if (thread == NULL) {
                pr_err("problem processing %d event, skipping it.\n",
                       event->header.type);
                goto repipe;
        }

        thread__find_addr_map(thread, session, cpumode, MAP__FUNCTION,
                              event->ip.pid, event->ip.ip, &al);

        if (al.map != NULL) {
                if (!al.map->dso->hit) {
                        al.map->dso->hit = 1;
                        if (map__load(al.map, NULL) >= 0) {
                                dso__inject_build_id(al.map->dso, session);
                                /*
                                 * If this fails, too bad, let the other side
                                 * account this as unresolved.
                                 */
                        } else
                                pr_warning("no symbols found in %s, maybe "
                                           "install a debug package?\n",
                                           al.map->dso->long_name);
                }
        }

repipe:
        event__repipe(event, sample, session);
        return 0;
}

struct perf_event_ops inject_ops = {
        .sample         = event__repipe,
        .mmap           = event__repipe,
        .comm           = event__repipe,
        .fork           = event__repipe,
        .exit           = event__repipe,
        .lost           = event__repipe,
        .read           = event__repipe,
        .throttle       = event__repipe,
        .unthrottle     = event__repipe,
        .attr           = event__repipe_synth,
        .event_type     = event__repipe_synth,
        .tracing_data   = event__repipe_synth,
        .build_id       = event__repipe_synth,
};

extern volatile int session_done;

static void sig_handler(int sig __attribute__((__unused__)))
{
        session_done = 1;
}

static int __cmd_inject(void)
{
        struct perf_session *session;
        int ret = -EINVAL;

        signal(SIGINT, sig_handler);

        if (inject_build_ids) {
                inject_ops.sample       = event__inject_buildid;
                inject_ops.mmap         = event__repipe_mmap;
                inject_ops.fork         = event__repipe_task;
                inject_ops.tracing_data = event__repipe_tracing_data;
        }

        session = perf_session__new(input_name, O_RDONLY, false, true, &inject_ops);
        if (session == NULL)
                return -ENOMEM;

        ret = perf_session__process_events(session, &inject_ops);

        perf_session__delete(session);

        return ret;
}

static const char * const report_usage[] = {
        "perf inject [<options>]",
        NULL
};

static const struct option options[] = {
        OPT_BOOLEAN('b', "build-ids", &inject_build_ids,
                    "Inject build-ids into the output stream"),
        OPT_INCR('v', "verbose", &verbose,
                 "be more verbose (show build ids, etc)"),
        OPT_END()
};

int cmd_inject(int argc, const char **argv, const char *prefix __used)
{
        argc = parse_options(argc, argv, options, report_usage, 0);

        /*
         * Any (unrecognized) arguments left?
         */
        if (argc)
                usage_with_options(report_usage, options);

        if (symbol__init() < 0)
                return -1;

        return __cmd_inject();
}