/*
 * Copyright (C) 2013 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <errno.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#include <sys/mman.h>

#include <hardware/memtrack.h>

#include "memtrack_msm.h"

#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
#define min(x, y) ((x) < (y) ? (x) : (y))

struct memtrack_record record_templates[] = {
    {
        .flags = MEMTRACK_FLAG_SMAPS_ACCOUNTED |
                 MEMTRACK_FLAG_PRIVATE |
                 MEMTRACK_FLAG_NONSECURE,
    },
    {
        .flags = MEMTRACK_FLAG_SMAPS_UNACCOUNTED |
                 MEMTRACK_FLAG_PRIVATE |
                 MEMTRACK_FLAG_NONSECURE,
    },
};

int kgsl_memtrack_get_memory(pid_t pid, enum memtrack_type type,
                             struct memtrack_record *records,
                             size_t *num_records)
{
    size_t allocated_records = min(*num_records, ARRAY_SIZE(record_templates));
    FILE *fp;
    char line[1024];
    char tmp[128];
    size_t accounted_size = 0;
    size_t unaccounted_size = 0;

    *num_records = ARRAY_SIZE(record_templates);

    /* fastpath to return the necessary number of records */
    if (allocated_records == 0) {
        return 0;
    }

    memcpy(records, record_templates,
           sizeof(struct memtrack_record) * allocated_records);

    snprintf(tmp, sizeof(tmp), "/d/kgsl/proc/%d/mem", pid);
    fp = fopen(tmp, "r");
    if (fp == NULL) {
        return -errno;
    }

    /* Go through each line of <pid>/mem file and for every entry of type "gpumem"
     * check if the gpubuffer entry is usermapped or not. If the entry is usermapped
     * count the entry as accounted else count the entry as unaccounted.
     */
    while (1) {
        unsigned long size, mapsize;
        char line_type[7];
        char flags[10];
        char line_usage[19];
        int ret, egl_surface_count = 0, egl_image_count = 0;

        if (fgets(line, sizeof(line), fp) == NULL) {
            break;
        }

        /* Format:
         *  gpuaddr useraddr     size    id flags       type            usage sglen mapsize eglsrf eglimg
         * 545ba000 545ba000     4096     1 -----pY     gpumem      arraybuffer     1  4096      0      0
         */
        ret = sscanf(line, "%*x %*x %lu %*d %9s %6s %18s %*d %lu %6d %6d\n",
                       &size, flags, line_type, line_usage, &mapsize,
                       &egl_surface_count, &egl_image_count);
        if (ret != 7) {
            continue;
        }

        if (size == 0)
            return -EINVAL;

        if (unaccounted_size + size < size)
            return -ERANGE;

        if (type == MEMTRACK_TYPE_GL && strcmp(line_type, "gpumem") == 0) {

            if (flags[6] == 'Y') {
                if (accounted_size + mapsize < accounted_size)
                    return -ERANGE;

                accounted_size += mapsize;

                if (mapsize > size)
                    return -EINVAL;

                unaccounted_size += size - mapsize;
            } else
                unaccounted_size += size;
        } else if (type == MEMTRACK_TYPE_GRAPHICS && strcmp(line_type, "ion") == 0) {
            if (strcmp(line_usage, "egl_surface") == 0)
                unaccounted_size += size;
            else if (egl_surface_count == 0)
                unaccounted_size += size / (egl_image_count ? egl_image_count : 1);
        }
    }

    if (allocated_records > 0) {
        records[0].size_in_bytes = accounted_size;
    }
    if (allocated_records > 1) {
        records[1].size_in_bytes = unaccounted_size;
    }

    fclose(fp);

    return 0;
}