#include <linux/types.h>
#include "event.h"
#include "debug.h"
#include "machine.h"
#include "sort.h"
#include "string.h"
#include "strlist.h"
#include "thread.h"
#include "thread_map.h"

static const char *perf_event__names[] = {
        [0]                                     = "TOTAL",
        [PERF_RECORD_MMAP]                      = "MMAP",
        [PERF_RECORD_MMAP2]                     = "MMAP2",
        [PERF_RECORD_LOST]                      = "LOST",
        [PERF_RECORD_COMM]                      = "COMM",
        [PERF_RECORD_EXIT]                      = "EXIT",
        [PERF_RECORD_THROTTLE]                  = "THROTTLE",
        [PERF_RECORD_UNTHROTTLE]                = "UNTHROTTLE",
        [PERF_RECORD_FORK]                      = "FORK",
        [PERF_RECORD_READ]                      = "READ",
        [PERF_RECORD_SAMPLE]                    = "SAMPLE",
        [PERF_RECORD_HEADER_ATTR]               = "ATTR",
        [PERF_RECORD_HEADER_EVENT_TYPE]         = "EVENT_TYPE",
        [PERF_RECORD_HEADER_TRACING_DATA]       = "TRACING_DATA",
        [PERF_RECORD_HEADER_BUILD_ID]           = "BUILD_ID",
        [PERF_RECORD_FINISHED_ROUND]            = "FINISHED_ROUND",
};

const char *perf_event__name(unsigned int id)
{
        if (id >= ARRAY_SIZE(perf_event__names))
                return "INVALID";
        if (!perf_event__names[id])
                return "UNKNOWN";
        return perf_event__names[id];
}

static struct perf_sample synth_sample = {
        .pid       = -1,
        .tid       = -1,
        .time      = -1,
        .stream_id = -1,
        .cpu       = -1,
        .period    = 1,
};

static pid_t perf_event__get_comm_tgid(pid_t pid, char *comm, size_t len)
{
        char filename[PATH_MAX];
        char bf[BUFSIZ];
        FILE *fp;
        size_t size = 0;
        pid_t tgid = -1;

        snprintf(filename, sizeof(filename), "/proc/%d/status", pid);

        fp = fopen(filename, "r");
        if (fp == NULL) {
                pr_debug("couldn't open %s\n", filename);
                return 0;
        }

        while (!comm[0] || (tgid < 0)) {
                if (fgets(bf, sizeof(bf), fp) == NULL) {
                        pr_warning("couldn't get COMM and pgid, malformed %s\n",
                                   filename);
                        break;
                }

                if (memcmp(bf, "Name:", 5) == 0) {
                        char *name = bf + 5;
                        while (*name && isspace(*name))
                                ++name;
                        size = strlen(name) - 1;
                        if (size >= len)
                                size = len - 1;
                        memcpy(comm, name, size);
                        comm[size] = '\0';

                } else if (memcmp(bf, "Tgid:", 5) == 0) {
                        char *tgids = bf + 5;
                        while (*tgids && isspace(*tgids))
                                ++tgids;
                        tgid = atoi(tgids);
                }
        }

        fclose(fp);

        return tgid;
}

static pid_t perf_event__synthesize_comm(struct perf_tool *tool,
                                         union perf_event *event, pid_t pid,
                                         int full,
                                         perf_event__handler_t process,
                                         struct machine *machine)
{
        char filename[PATH_MAX];
        size_t size;
        DIR *tasks;
        struct dirent dirent, *next;
        pid_t tgid;

        memset(&event->comm, 0, sizeof(event->comm));

        tgid = perf_event__get_comm_tgid(pid, event->comm.comm,
                                         sizeof(event->comm.comm));
        if (tgid < 0)
                goto out;

        event->comm.pid = tgid;
        event->comm.header.type = PERF_RECORD_COMM;

        size = strlen(event->comm.comm) + 1;
        size = PERF_ALIGN(size, sizeof(u64));
        memset(event->comm.comm + size, 0, machine->id_hdr_size);
        event->comm.header.size = (sizeof(event->comm) -
                                (sizeof(event->comm.comm) - size) +
                                machine->id_hdr_size);
        if (!full) {
                event->comm.tid = pid;

                if (process(tool, event, &synth_sample, machine) != 0)
                        return -1;

                goto out;
        }

        snprintf(filename, sizeof(filename), "/proc/%d/task", pid);

        tasks = opendir(filename);
        if (tasks == NULL) {
                pr_debug("couldn't open %s\n", filename);
                return 0;
        }

        while (!readdir_r(tasks, &dirent, &next) && next) {
                char *end;
                pid = strtol(dirent.d_name, &end, 10);
                if (*end)
                        continue;

                /* already have tgid; jut want to update the comm */
                (void) perf_event__get_comm_tgid(pid, event->comm.comm,
                                         sizeof(event->comm.comm));

                size = strlen(event->comm.comm) + 1;
                size = PERF_ALIGN(size, sizeof(u64));
                memset(event->comm.comm + size, 0, machine->id_hdr_size);
                event->comm.header.size = (sizeof(event->comm) -
                                          (sizeof(event->comm.comm) - size) +
                                          machine->id_hdr_size);

                event->comm.tid = pid;

                if (process(tool, event, &synth_sample, machine) != 0) {
                        tgid = -1;
                        break;
                }
        }

        closedir(tasks);
out:
        return tgid;
}

static int perf_event__synthesize_mmap_events(struct perf_tool *tool,
                                              union perf_event *event,
                                              pid_t pid, pid_t tgid,
                                              perf_event__handler_t process,
                                              struct machine *machine)
{
        char filename[PATH_MAX];
        FILE *fp;
        int rc = 0;

        snprintf(filename, sizeof(filename), "/proc/%d/maps", pid);

        fp = fopen(filename, "r");
        if (fp == NULL) {
                /*
                 * We raced with a task exiting - just return:
                 */
                pr_debug("couldn't open %s\n", filename);
                return -1;
        }

        event->header.type = PERF_RECORD_MMAP;
        /*
         * Just like the kernel, see __perf_event_mmap in kernel/perf_event.c
         */
        event->header.misc = PERF_RECORD_MISC_USER;

        while (1) {
                char bf[BUFSIZ];
                char prot[5];
                char execname[PATH_MAX];
                char anonstr[] = "//anon";
                size_t size;
                ssize_t n;

                if (fgets(bf, sizeof(bf), fp) == NULL)
                        break;

                /* ensure null termination since stack will be reused. */
                strcpy(execname, "");

                /* 00400000-0040c000 r-xp 00000000 fd:01 41038  /bin/cat */
                n = sscanf(bf, "%"PRIx64"-%"PRIx64" %s %"PRIx64" %*x:%*x %*u %s\n",
                       &event->mmap.start, &event->mmap.len, prot,
                       &event->mmap.pgoff,
                       execname);

                if (n != 5)
                        continue;

                if (prot[2] != 'x')
                        continue;

                if (!strcmp(execname, ""))
                        strcpy(execname, anonstr);

                size = strlen(execname) + 1;
                memcpy(event->mmap.filename, execname, size);
                size = PERF_ALIGN(size, sizeof(u64));
                event->mmap.len -= event->mmap.start;
                event->mmap.header.size = (sizeof(event->mmap) -
                                        (sizeof(event->mmap.filename) - size));
                memset(event->mmap.filename + size, 0, machine->id_hdr_size);
                event->mmap.header.size += machine->id_hdr_size;
                event->mmap.pid = tgid;
                event->mmap.tid = pid;

                if (process(tool, event, &synth_sample, machine) != 0) {
                        rc = -1;
                        break;
                }
        }

        fclose(fp);
        return rc;
}

int perf_event__synthesize_modules(struct perf_tool *tool,
                                   perf_event__handler_t process,
                                   struct machine *machine)
{
        int rc = 0;
        struct rb_node *nd;
        struct map_groups *kmaps = &machine->kmaps;
        union perf_event *event = zalloc((sizeof(event->mmap) +
                                          machine->id_hdr_size));
        if (event == NULL) {
                pr_debug("Not enough memory synthesizing mmap event "
                         "for kernel modules\n");
                return -1;
        }

        event->header.type = PERF_RECORD_MMAP;

        /*
         * kernel uses 0 for user space maps, see kernel/perf_event.c
         * __perf_event_mmap
         */
        if (machine__is_host(machine))
                event->header.misc = PERF_RECORD_MISC_KERNEL;
        else
                event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;

        for (nd = rb_first(&kmaps->maps[MAP__FUNCTION]);
             nd; nd = rb_next(nd)) {
                size_t size;
                struct map *pos = rb_entry(nd, struct map, rb_node);

                if (pos->dso->kernel)
                        continue;

                size = PERF_ALIGN(pos->dso->long_name_len + 1, sizeof(u64));
                event->mmap.header.type = PERF_RECORD_MMAP;
                event->mmap.header.size = (sizeof(event->mmap) -
                                        (sizeof(event->mmap.filename) - size));
                memset(event->mmap.filename + size, 0, machine->id_hdr_size);
                event->mmap.header.size += machine->id_hdr_size;
                event->mmap.start = pos->start;
                event->mmap.len   = pos->end - pos->start;
                event->mmap.pid   = machine->pid;

                memcpy(event->mmap.filename, pos->dso->long_name,
                       pos->dso->long_name_len + 1);
                if (process(tool, event, &synth_sample, machine) != 0) {
                        rc = -1;
                        break;
                }
        }

        free(event);
        return rc;
}

static int __event__synthesize_thread(union perf_event *comm_event,
                                      union perf_event *mmap_event,
                                      pid_t pid, int full,
                                          perf_event__handler_t process,
                                      struct perf_tool *tool,
                                      struct machine *machine)
{
        pid_t tgid = perf_event__synthesize_comm(tool, comm_event, pid, full,
                                                 process, machine);
        if (tgid == -1)
                return -1;
        return perf_event__synthesize_mmap_events(tool, mmap_event, pid, tgid,
                                                  process, machine);
}

int perf_event__synthesize_thread_map(struct perf_tool *tool,
                                      struct thread_map *threads,
                                      perf_event__handler_t process,
                                      struct machine *machine)
{
        union perf_event *comm_event, *mmap_event;
        int err = -1, thread, j;

        comm_event = malloc(sizeof(comm_event->comm) + machine->id_hdr_size);
        if (comm_event == NULL)
                goto out;

        mmap_event = malloc(sizeof(mmap_event->mmap) + machine->id_hdr_size);
        if (mmap_event == NULL)
                goto out_free_comm;

        err = 0;
        for (thread = 0; thread < threads->nr; ++thread) {
                if (__event__synthesize_thread(comm_event, mmap_event,
                                               threads->map[thread], 0,
                                               process, tool, machine)) {
                        err = -1;
                        break;
                }

                /*
                 * comm.pid is set to thread group id by
                 * perf_event__synthesize_comm
                 */
                if ((int) comm_event->comm.pid != threads->map[thread]) {
                        bool need_leader = true;

                        /* is thread group leader in thread_map? */
                        for (j = 0; j < threads->nr; ++j) {
                                if ((int) comm_event->comm.pid == threads->map[j]) {
                                        need_leader = false;
                                        break;
                                }
                        }

                        /* if not, generate events for it */
                        if (need_leader &&
                            __event__synthesize_thread(comm_event,
                                                      mmap_event,
                                                      comm_event->comm.pid, 0,
                                                      process, tool, machine)) {
                                err = -1;
                                break;
                        }
                }
        }
        free(mmap_event);
out_free_comm:
        free(comm_event);
out:
        return err;
}

int perf_event__synthesize_threads(struct perf_tool *tool,
                                   perf_event__handler_t process,
                                   struct machine *machine)
{
        DIR *proc;
        struct dirent dirent, *next;
        union perf_event *comm_event, *mmap_event;
        int err = -1;

        comm_event = malloc(sizeof(comm_event->comm) + machine->id_hdr_size);
        if (comm_event == NULL)
                goto out;

        mmap_event = malloc(sizeof(mmap_event->mmap) + machine->id_hdr_size);
        if (mmap_event == NULL)
                goto out_free_comm;

        proc = opendir("/proc");
        if (proc == NULL)
                goto out_free_mmap;

        while (!readdir_r(proc, &dirent, &next) && next) {
                char *end;
                pid_t pid = strtol(dirent.d_name, &end, 10);

                if (*end) /* only interested in proper numerical dirents */
                        continue;
                /*
                 * We may race with exiting thread, so don't stop just because
                 * one thread couldn't be synthesized.
                 */
                __event__synthesize_thread(comm_event, mmap_event, pid, 1,
                                           process, tool, machine);
        }

        err = 0;
        closedir(proc);
out_free_mmap:
        free(mmap_event);
out_free_comm:
        free(comm_event);
out:
        return err;
}

struct process_symbol_args {
        const char *name;
        u64        start;
};

static int find_symbol_cb(void *arg, const char *name, char type,
                          u64 start)
{
        struct process_symbol_args *args = arg;

        /*
         * Must be a function or at least an alias, as in PARISC64, where "_text" is
         * an 'A' to the same address as "_stext".
         */
        if (!(symbol_type__is_a(type, MAP__FUNCTION) ||
              type == 'A') || strcmp(name, args->name))
                return 0;

        args->start = start;
        return 1;
}

int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
                                       perf_event__handler_t process,
                                       struct machine *machine,
                                       const char *symbol_name)
{
        size_t size;
        const char *filename, *mmap_name;
        char path[PATH_MAX];
        char name_buff[PATH_MAX];
        struct map *map;
        int err;
        /*
         * We should get this from /sys/kernel/sections/.text, but till that is
         * available use this, and after it is use this as a fallback for older
         * kernels.
         */
        struct process_symbol_args args = { .name = symbol_name, };
        union perf_event *event = zalloc((sizeof(event->mmap) +
                                          machine->id_hdr_size));
        if (event == NULL) {
                pr_debug("Not enough memory synthesizing mmap event "
                         "for kernel modules\n");
                return -1;
        }

        mmap_name = machine__mmap_name(machine, name_buff, sizeof(name_buff));
        if (machine__is_host(machine)) {
                /*
                 * kernel uses PERF_RECORD_MISC_USER for user space maps,
                 * see kernel/perf_event.c __perf_event_mmap
                 */
                event->header.misc = PERF_RECORD_MISC_KERNEL;
                filename = "/proc/kallsyms";
        } else {
                event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
                if (machine__is_default_guest(machine))
                        filename = (char *) symbol_conf.default_guest_kallsyms;
                else {
                        sprintf(path, "%s/proc/kallsyms", machine->root_dir);
                        filename = path;
                }
        }

        if (kallsyms__parse(filename, &args, find_symbol_cb) <= 0) {
                free(event);
                return -ENOENT;
        }

        map = machine->vmlinux_maps[MAP__FUNCTION];
        size = snprintf(event->mmap.filename, sizeof(event->mmap.filename),
                        "%s%s", mmap_name, symbol_name) + 1;
        size = PERF_ALIGN(size, sizeof(u64));
        event->mmap.header.type = PERF_RECORD_MMAP;
        event->mmap.header.size = (sizeof(event->mmap) -
                        (sizeof(event->mmap.filename) - size) + machine->id_hdr_size);
        event->mmap.pgoff = args.start;
        event->mmap.start = map->start;
        event->mmap.len   = map->end - event->mmap.start;
        event->mmap.pid   = machine->pid;

        err = process(tool, event, &synth_sample, machine);
        free(event);

        return err;
}

size_t perf_event__fprintf_comm(union perf_event *event, FILE *fp)
{
        return fprintf(fp, ": %s:%d\n", event->comm.comm, event->comm.tid);
}

int perf_event__process_comm(struct perf_tool *tool __maybe_unused,
                             union perf_event *event,
                             struct perf_sample *sample __maybe_unused,
                             struct machine *machine)
{
        return machine__process_comm_event(machine, event);
}

int perf_event__process_lost(struct perf_tool *tool __maybe_unused,
                             union perf_event *event,
                             struct perf_sample *sample __maybe_unused,
                             struct machine *machine)
{
        return machine__process_lost_event(machine, event);
}

size_t perf_event__fprintf_mmap(union perf_event *event, FILE *fp)
{
        return fprintf(fp, " %d/%d: [%#" PRIx64 "(%#" PRIx64 ") @ %#" PRIx64 "]: %s\n",
                       event->mmap.pid, event->mmap.tid, event->mmap.start,
                       event->mmap.len, event->mmap.pgoff, event->mmap.filename);
}

size_t perf_event__fprintf_mmap2(union perf_event *event, FILE *fp)
{
        return fprintf(fp, " %d/%d: [%#" PRIx64 "(%#" PRIx64 ") @ %#" PRIx64
                           " %02x:%02x %"PRIu64" %"PRIu64"]: %s\n",
                       event->mmap2.pid, event->mmap2.tid, event->mmap2.start,
                       event->mmap2.len, event->mmap2.pgoff, event->mmap2.maj,
                       event->mmap2.min, event->mmap2.ino,
                       event->mmap2.ino_generation,
                       event->mmap2.filename);
}

int perf_event__process_mmap(struct perf_tool *tool __maybe_unused,
                             union perf_event *event,
                             struct perf_sample *sample __maybe_unused,
                             struct machine *machine)
{
        return machine__process_mmap_event(machine, event);
}

int perf_event__process_mmap2(struct perf_tool *tool __maybe_unused,
                             union perf_event *event,
                             struct perf_sample *sample __maybe_unused,
                             struct machine *machine)
{
        return machine__process_mmap2_event(machine, event);
}

size_t perf_event__fprintf_task(union perf_event *event, FILE *fp)
{
        return fprintf(fp, "(%d:%d):(%d:%d)\n",
                       event->fork.pid, event->fork.tid,
                       event->fork.ppid, event->fork.ptid);
}

int perf_event__process_fork(struct perf_tool *tool __maybe_unused,
                             union perf_event *event,
                             struct perf_sample *sample __maybe_unused,
                             struct machine *machine)
{
        return machine__process_fork_event(machine, event);
}

int perf_event__process_exit(struct perf_tool *tool __maybe_unused,
                             union perf_event *event,
                             struct perf_sample *sample __maybe_unused,
                             struct machine *machine)
{
        return machine__process_exit_event(machine, event);
}

size_t perf_event__fprintf(union perf_event *event, FILE *fp)
{
        size_t ret = fprintf(fp, "PERF_RECORD_%s",
                             perf_event__name(event->header.type));

        switch (event->header.type) {
        case PERF_RECORD_COMM:
                ret += perf_event__fprintf_comm(event, fp);
                break;
        case PERF_RECORD_FORK:
        case PERF_RECORD_EXIT:
                ret += perf_event__fprintf_task(event, fp);
                break;
        case PERF_RECORD_MMAP:
                ret += perf_event__fprintf_mmap(event, fp);
                break;
        case PERF_RECORD_MMAP2:
                ret += perf_event__fprintf_mmap2(event, fp);
                break;
        default:
                ret += fprintf(fp, "\n");
        }

        return ret;
}

int perf_event__process(struct perf_tool *tool __maybe_unused,
                        union perf_event *event,
                        struct perf_sample *sample __maybe_unused,
                        struct machine *machine)
{
        return machine__process_event(machine, event);
}

void thread__find_addr_map(struct thread *self,
                           struct machine *machine, u8 cpumode,
                           enum map_type type, u64 addr,
                           struct addr_location *al)
{
        struct map_groups *mg = &self->mg;
        bool load_map = false;

        al->thread = self;
        al->addr = addr;
        al->cpumode = cpumode;
        al->filtered = false;

        if (machine == NULL) {
                al->map = NULL;
                return;
        }

        if (cpumode == PERF_RECORD_MISC_KERNEL && perf_host) {
                al->level = 'k';
                mg = &machine->kmaps;
                load_map = true;
        } else if (cpumode == PERF_RECORD_MISC_USER && perf_host) {
                al->level = '.';
        } else if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest) {
                al->level = 'g';
                mg = &machine->kmaps;
                load_map = true;
        } else {
                /*
                 * 'u' means guest os user space.
                 * TODO: We don't support guest user space. Might support late.
                 */
                if (cpumode == PERF_RECORD_MISC_GUEST_USER && perf_guest)
                        al->level = 'u';
                else
                        al->level = 'H';
                al->map = NULL;

                if ((cpumode == PERF_RECORD_MISC_GUEST_USER ||
                        cpumode == PERF_RECORD_MISC_GUEST_KERNEL) &&
                        !perf_guest)
                        al->filtered = true;
                if ((cpumode == PERF_RECORD_MISC_USER ||
                        cpumode == PERF_RECORD_MISC_KERNEL) &&
                        !perf_host)
                        al->filtered = true;

                return;
        }
try_again:
        al->map = map_groups__find(mg, type, al->addr);
        if (al->map == NULL) {
                /*
                 * If this is outside of all known maps, and is a negative
                 * address, try to look it up in the kernel dso, as it might be
                 * a vsyscall or vdso (which executes in user-mode).
                 *
                 * XXX This is nasty, we should have a symbol list in the
                 * "[vdso]" dso, but for now lets use the old trick of looking
                 * in the whole kernel symbol list.
                 */
                if ((long long)al->addr < 0 &&
                    cpumode == PERF_RECORD_MISC_USER &&
                    machine && mg != &machine->kmaps) {
                        mg = &machine->kmaps;
                        goto try_again;
                }
        } else {
                /*
                 * Kernel maps might be changed when loading symbols so loading
                 * must be done prior to using kernel maps.
                 */
                if (load_map)
                        map__load(al->map, machine->symbol_filter);
                al->addr = al->map->map_ip(al->map, al->addr);
        }
}

void thread__find_addr_location(struct thread *thread, struct machine *machine,
                                u8 cpumode, enum map_type type, u64 addr,
                                struct addr_location *al)
{
        thread__find_addr_map(thread, machine, cpumode, type, addr, al);
        if (al->map != NULL)
                al->sym = map__find_symbol(al->map, al->addr,
                                           machine->symbol_filter);
        else
                al->sym = NULL;
}

int perf_event__preprocess_sample(const union perf_event *event,
                                  struct machine *machine,
                                  struct addr_location *al,
                                  struct perf_sample *sample)
{
        u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
        struct thread *thread = machine__findnew_thread(machine, sample->pid,
                                                        sample->pid);

        if (thread == NULL)
                return -1;

        if (symbol_conf.comm_list &&
            !strlist__has_entry(symbol_conf.comm_list, thread->comm))
                goto out_filtered;

        dump_printf(" ... thread: %s:%d\n", thread->comm, thread->tid);
        /*
         * Have we already created the kernel maps for this machine?
         *
         * This should have happened earlier, when we processed the kernel MMAP
         * events, but for older perf.data files there was no such thing, so do
         * it now.
         */
        if (cpumode == PERF_RECORD_MISC_KERNEL &&
            machine->vmlinux_maps[MAP__FUNCTION] == NULL)
                machine__create_kernel_maps(machine);

        thread__find_addr_map(thread, machine, cpumode, MAP__FUNCTION,
                              sample->ip, al);
        dump_printf(" ...... dso: %s\n",
                    al->map ? al->map->dso->long_name :
                        al->level == 'H' ? "[hypervisor]" : "<not found>");
        al->sym = NULL;
        al->cpu = sample->cpu;

        if (al->map) {
                struct dso *dso = al->map->dso;

                if (symbol_conf.dso_list &&
                    (!dso || !(strlist__has_entry(symbol_conf.dso_list,
                                                  dso->short_name) ||
                               (dso->short_name != dso->long_name &&
                                strlist__has_entry(symbol_conf.dso_list,
                                                   dso->long_name)))))
                        goto out_filtered;

                al->sym = map__find_symbol(al->map, al->addr,
                                           machine->symbol_filter);
        }

        if (symbol_conf.sym_list &&
                (!al->sym || !strlist__has_entry(symbol_conf.sym_list,
                                                al->sym->name)))
                goto out_filtered;

        return 0;

out_filtered:
        al->filtered = true;
        return 0;
}