// SPDX-License-Identifier: GPL-2.0
#include "unwind.h"
#include "dso.h"
#include "map.h"
#include "thread.h"
#include "session.h"
#include "debug.h"
#include "env.h"
#include "callchain.h"

struct unwind_libunwind_ops __weak *local_unwind_libunwind_ops;
struct unwind_libunwind_ops __weak *x86_32_unwind_libunwind_ops;
struct unwind_libunwind_ops __weak *arm64_unwind_libunwind_ops;

int unwind__prepare_access(struct maps *maps, struct map *map, bool *initialized)
{
        const char *arch;
        enum dso_type dso_type;
        struct unwind_libunwind_ops *ops = local_unwind_libunwind_ops;
        struct dso *dso = map__dso(map);
        struct machine *machine;
        int err;

        if (!dwarf_callchain_users)
                return 0;

        if (maps__addr_space(maps)) {
                pr_debug("unwind: thread map already set, dso=%s\n", dso__name(dso));
                if (initialized)
                        *initialized = true;
                return 0;
        }

        machine = maps__machine(maps);
        /* env->arch is NULL for live-mode (i.e. perf top) */
        if (!machine->env || !machine->env->arch)
                goto out_register;

        dso_type = dso__type(dso, machine);
        if (dso_type == DSO__TYPE_UNKNOWN)
                return 0;

        arch = perf_env__arch(machine->env);

        if (!strcmp(arch, "x86")) {
                if (dso_type != DSO__TYPE_64BIT)
                        ops = x86_32_unwind_libunwind_ops;
        } else if (!strcmp(arch, "arm64") || !strcmp(arch, "arm")) {
                if (dso_type == DSO__TYPE_64BIT)
                        ops = arm64_unwind_libunwind_ops;
        }

        if (!ops) {
                pr_warning_once("unwind: target platform=%s is not supported\n", arch);
                return 0;
        }
out_register:
        maps__set_unwind_libunwind_ops(maps, ops);

        err = maps__unwind_libunwind_ops(maps)->prepare_access(maps);
        if (initialized)
                *initialized = err ? false : true;
        return err;
}

void unwind__flush_access(struct maps *maps)
{
        const struct unwind_libunwind_ops *ops = maps__unwind_libunwind_ops(maps);

        if (ops)
                ops->flush_access(maps);
}

void unwind__finish_access(struct maps *maps)
{
        const struct unwind_libunwind_ops *ops = maps__unwind_libunwind_ops(maps);

        if (ops)
                ops->finish_access(maps);
}

int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
                         struct thread *thread,
                         struct perf_sample *data, int max_stack,
                         bool best_effort)
{
        const struct unwind_libunwind_ops *ops = maps__unwind_libunwind_ops(thread__maps(thread));

        if (ops)
                return ops->get_entries(cb, arg, thread, data, max_stack, best_effort);
        return 0;
}