// SPDX-License-Identifier: GPL-2.0-only
/*
 *
 * Copyright (C) 2015 Naveen N. Rao, IBM Corporation
 */

#include "dso.h"
#include "symbol.h"
#include "map.h"
#include "probe-event.h"
#include "probe-file.h"

int arch__choose_best_symbol(struct symbol *syma,
                             struct symbol *symb __maybe_unused)
{
        char *sym = syma->name;

#if !defined(_CALL_ELF) || _CALL_ELF != 2
        /* Skip over any initial dot */
        if (*sym == '.')
                sym++;
#endif

        /* Avoid "SyS" kernel syscall aliases */
        if (strlen(sym) >= 3 && !strncmp(sym, "SyS", 3))
                return SYMBOL_B;
        if (strlen(sym) >= 10 && !strncmp(sym, "compat_SyS", 10))
                return SYMBOL_B;

        return SYMBOL_A;
}

#if !defined(_CALL_ELF) || _CALL_ELF != 2
/* Allow matching against dot variants */
int arch__compare_symbol_names(const char *namea, const char *nameb)
{
        /* Skip over initial dot */
        if (*namea == '.')
                namea++;
        if (*nameb == '.')
                nameb++;

        return strcmp(namea, nameb);
}

int arch__compare_symbol_names_n(const char *namea, const char *nameb,
                                 unsigned int n)
{
        /* Skip over initial dot */
        if (*namea == '.')
                namea++;
        if (*nameb == '.')
                nameb++;

        return strncmp(namea, nameb, n);
}

const char *arch__normalize_symbol_name(const char *name)
{
        /* Skip over initial dot */
        if (name && *name == '.')
                name++;
        return name;
}
#endif

#if defined(_CALL_ELF) && _CALL_ELF == 2

#ifdef HAVE_LIBELF_SUPPORT
void arch__sym_update(struct symbol *s, GElf_Sym *sym)
{
        s->arch_sym = sym->st_other;
}
#endif

#define PPC64LE_LEP_OFFSET      8

void arch__fix_tev_from_maps(struct perf_probe_event *pev,
                             struct probe_trace_event *tev, struct map *map,
                             struct symbol *sym)
{
        int lep_offset;

        /*
         * When probing at a function entry point, we normally always want the
         * LEP since that catches calls to the function through both the GEP and
         * the LEP. Hence, we would like to probe at an offset of 8 bytes if
         * the user only specified the function entry.
         *
         * However, if the user specifies an offset, we fall back to using the
         * GEP since all userspace applications (objdump/readelf) show function
         * disassembly with offsets from the GEP.
         */
        if (pev->point.offset || !map || !sym)
                return;

        /* For kretprobes, add an offset only if the kernel supports it */
        if (!pev->uprobes && pev->point.retprobe) {
#ifdef HAVE_LIBELF_SUPPORT
                if (!kretprobe_offset_is_supported())
#endif
                        return;
        }

        lep_offset = PPC64_LOCAL_ENTRY_OFFSET(sym->arch_sym);

        if (map__dso(map)->symtab_type == DSO_BINARY_TYPE__KALLSYMS)
                tev->point.offset += PPC64LE_LEP_OFFSET;
        else if (lep_offset) {
                if (pev->uprobes)
                        tev->point.address += lep_offset;
                else
                        tev->point.offset += lep_offset;
        }
}

#ifdef HAVE_LIBELF_SUPPORT
void arch__post_process_probe_trace_events(struct perf_probe_event *pev,
                                           int ntevs)
{
        struct probe_trace_event *tev;
        struct map *map;
        struct symbol *sym = NULL;
        struct rb_node *tmp;
        int i = 0;

        map = get_target_map(pev->target, pev->nsi, pev->uprobes);
        if (!map || map__load(map) < 0)
                return;

        for (i = 0; i < ntevs; i++) {
                tev = &pev->tevs[i];
                map__for_each_symbol(map, sym, tmp) {
                        if (map__unmap_ip(map, sym->start) == tev->point.address) {
                                arch__fix_tev_from_maps(pev, tev, map, sym);
                                break;
                        }
                }
        }
}
#endif /* HAVE_LIBELF_SUPPORT */

#endif