// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2009, Steven Rostedt <srostedt@redhat.com>
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

#include "debug.h"
#include "trace-event.h"

#include <linux/ctype.h>
#include <linux/kernel.h>
#include <event-parse.h>

static int get_common_field(struct scripting_context *context,
                            int *offset, int *size, const char *type)
{
        struct tep_handle *pevent = context->pevent;
        struct tep_event *event;
        struct tep_format_field *field;

        if (!*size) {

                event = tep_get_first_event(pevent);
                if (!event)
                        return 0;

                field = tep_find_common_field(event, type);
                if (!field)
                        return 0;
                *offset = field->offset;
                *size = field->size;
        }

        return tep_read_number(pevent, context->event_data + *offset, *size);
}

int common_lock_depth(struct scripting_context *context)
{
        static int offset;
        static int size;
        int ret;

        ret = get_common_field(context, &size, &offset,
                               "common_lock_depth");
        if (ret < 0)
                return -1;

        return ret;
}

int common_flags(struct scripting_context *context)
{
        static int offset;
        static int size;
        int ret;

        ret = get_common_field(context, &size, &offset,
                               "common_flags");
        if (ret < 0)
                return -1;

        return ret;
}

int common_pc(struct scripting_context *context)
{
        static int offset;
        static int size;
        int ret;

        ret = get_common_field(context, &size, &offset,
                               "common_preempt_count");
        if (ret < 0)
                return -1;

        return ret;
}

unsigned long long
raw_field_value(struct tep_event *event, const char *name, void *data)
{
        struct tep_format_field *field;
        unsigned long long val;

        field = tep_find_any_field(event, name);
        if (!field)
                return 0ULL;

        tep_read_number_field(field, data, &val);

        return val;
}

unsigned long long read_size(struct tep_event *event, void *ptr, int size)
{
        return tep_read_number(event->tep, ptr, size);
}

void event_format__fprintf(const struct tep_event *event,
                           int cpu, void *data, int size, FILE *fp)
{
        struct tep_record record;
        struct trace_seq s;

        memset(&record, 0, sizeof(record));
        record.cpu = cpu;
        record.size = size;
        record.data = data;

        trace_seq_init(&s);
        tep_print_event(event->tep, &s, &record, "%s", TEP_PRINT_INFO);
        trace_seq_do_fprintf(&s, fp);
        trace_seq_destroy(&s);
}

/*
 * prev_state is of size long, which is 32 bits on 32 bit architectures.
 * As it needs to have the same bits for both 32 bit and 64 bit architectures
 * we can just assume that the flags we care about will all be within
 * the 32 bits.
 */
#define MAX_STATE_BITS 32

static const char *convert_sym(struct tep_print_flag_sym *sym)
{
        static char save_states[MAX_STATE_BITS + 1];

        memset(save_states, 0, sizeof(save_states));

        /* This is the flags for the prev_state_field, now make them into a string */
        for (; sym; sym = sym->next) {
                long bitmask = strtoul(sym->value, NULL, 0);
                int i;

                for (i = 0; !(bitmask & 1); i++)
                        bitmask >>= 1;

                if (i >= MAX_STATE_BITS)
                        continue;

                save_states[i] = sym->str[0];
        }

        return save_states;
}

static struct tep_print_arg_field *
find_arg_field(struct tep_format_field *prev_state_field, struct tep_print_arg *arg)
{
        struct tep_print_arg_field *field;

        if (!arg)
                return NULL;

        if (arg->type == TEP_PRINT_FIELD)
                return &arg->field;

        if (arg->type == TEP_PRINT_OP) {
                field = find_arg_field(prev_state_field, arg->op.left);
                if (field && field->field == prev_state_field)
                        return field;
                field = find_arg_field(prev_state_field, arg->op.right);
                if (field && field->field == prev_state_field)
                        return field;
        }
        return NULL;
}

static struct tep_print_flag_sym *
test_flags(struct tep_format_field *prev_state_field, struct tep_print_arg *arg)
{
        struct tep_print_arg_field *field;

        field = find_arg_field(prev_state_field, arg->flags.field);
        if (!field)
                return NULL;

        return arg->flags.flags;
}

static struct tep_print_flag_sym *
search_op(struct tep_format_field *prev_state_field, struct tep_print_arg *arg)
{
        struct tep_print_flag_sym *sym = NULL;

        if (!arg)
                return NULL;

        if (arg->type == TEP_PRINT_OP) {
                sym = search_op(prev_state_field, arg->op.left);
                if (sym)
                        return sym;

                sym = search_op(prev_state_field, arg->op.right);
                if (sym)
                        return sym;
        } else if (arg->type == TEP_PRINT_FLAGS) {
                sym = test_flags(prev_state_field, arg);
        }

        return sym;
}

const char *parse_task_states(struct tep_format_field *state_field)
{
        struct tep_print_flag_sym *sym;
        struct tep_print_arg *arg;
        struct tep_event *event;

        event = state_field->event;

        /*
         * Look at the event format fields, and search for where
         * the prev_state is parsed via the format flags.
         */
        for (arg = event->print_fmt.args; arg; arg = arg->next) {
                /*
                 * Currently, the __print_flags() for the prev_state
                 * is embedded in operations, so they too must be
                 * searched.
                 */
                sym = search_op(state_field, arg);
                if (sym)
                        return convert_sym(sym);
        }
        return NULL;
}

void parse_ftrace_printk(struct tep_handle *pevent,
                         char *file, unsigned int size __maybe_unused)
{
        unsigned long long addr;
        char *printk;
        char *line;
        char *next = NULL;
        char *addr_str;
        char *fmt = NULL;

        line = strtok_r(file, "\n", &next);
        while (line) {
                addr_str = strtok_r(line, ":", &fmt);
                if (!addr_str) {
                        pr_warning("printk format with empty entry");
                        break;
                }
                addr = strtoull(addr_str, NULL, 16);
                /* fmt still has a space, skip it */
                printk = strdup(fmt+1);
                line = strtok_r(NULL, "\n", &next);
                tep_register_print_string(pevent, printk, addr);
                free(printk);
        }
}

void parse_saved_cmdline(struct tep_handle *pevent,
                         char *file, unsigned int size __maybe_unused)
{
        char comm[17]; /* Max comm length in the kernel is 16. */
        char *line;
        char *next = NULL;
        int pid;

        line = strtok_r(file, "\n", &next);
        while (line) {
                if (sscanf(line, "%d %16s", &pid, comm) == 2)
                        tep_register_comm(pevent, comm, pid);
                line = strtok_r(NULL, "\n", &next);
        }
}

int parse_ftrace_file(struct tep_handle *pevent, char *buf, unsigned long size)
{
        return tep_parse_event(pevent, buf, size, "ftrace");
}

int parse_event_file(struct tep_handle *pevent,
                     char *buf, unsigned long size, char *sys)
{
        return tep_parse_event(pevent, buf, size, sys);
}

struct flag {
        const char *name;
        unsigned long long value;
};

static const struct flag flags[] = {
        { "HI_SOFTIRQ", 0 },
        { "TIMER_SOFTIRQ", 1 },
        { "NET_TX_SOFTIRQ", 2 },
        { "NET_RX_SOFTIRQ", 3 },
        { "BLOCK_SOFTIRQ", 4 },
        { "IRQ_POLL_SOFTIRQ", 5 },
        { "TASKLET_SOFTIRQ", 6 },
        { "SCHED_SOFTIRQ", 7 },
        { "HRTIMER_SOFTIRQ", 8 },
        { "RCU_SOFTIRQ", 9 },

        { "HRTIMER_NORESTART", 0 },
        { "HRTIMER_RESTART", 1 },
};

unsigned long long eval_flag(const char *flag)
{
        int i;

        /*
         * Some flags in the format files do not get converted.
         * If the flag is not numeric, see if it is something that
         * we already know about.
         */
        if (isdigit(flag[0]))
                return strtoull(flag, NULL, 0);

        for (i = 0; i < (int)(ARRAY_SIZE(flags)); i++)
                if (strcmp(flags[i].name, flag) == 0)
                        return flags[i].value;

        return 0;
}