// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
 *
 * Module Name: apfiles - File-related functions for acpidump utility
 *
 * Copyright (C) 2000 - 2025, Intel Corp.
 *
 *****************************************************************************/

#include "acpidump.h"

/* Local prototypes */

static int ap_is_existing_file(char *pathname);

/******************************************************************************
 *
 * FUNCTION:    ap_is_existing_file
 *
 * PARAMETERS:  pathname            - Output filename
 *
 * RETURN:      0 on success
 *
 * DESCRIPTION: Query for file overwrite if it already exists.
 *
 ******************************************************************************/

static int ap_is_existing_file(char *pathname)
{
#if !defined(_GNU_EFI) && !defined(_EDK2_EFI)
        struct stat stat_info;
        int in_char;

        if (!stat(pathname, &stat_info)) {
                fprintf(stderr,
                        "Target path already exists, overwrite? [y|n] ");

                in_char = fgetc(stdin);
                if (in_char == '\n') {
                        in_char = fgetc(stdin);
                }

                if (in_char != 'y' && in_char != 'Y') {
                        return (-1);
                }
        }
#endif

        return (0);
}

/******************************************************************************
 *
 * FUNCTION:    ap_open_output_file
 *
 * PARAMETERS:  pathname            - Output filename
 *
 * RETURN:      Open file handle
 *
 * DESCRIPTION: Open a text output file for acpidump. Checks if file already
 *              exists.
 *
 ******************************************************************************/

int ap_open_output_file(char *pathname)
{
        ACPI_FILE file;

        /* If file exists, prompt for overwrite */

        if (ap_is_existing_file(pathname) != 0) {
                return (-1);
        }

        /* Point stdout to the file */

        file = fopen(pathname, "w");
        if (!file) {
                fprintf(stderr, "Could not open output file: %s\n", pathname);
                return (-1);
        }

        /* Save the file and path */

        gbl_output_file = file;
        gbl_output_filename = pathname;
        return (0);
}

/******************************************************************************
 *
 * FUNCTION:    ap_write_to_binary_file
 *
 * PARAMETERS:  table               - ACPI table to be written
 *              instance            - ACPI table instance no. to be written
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Write an ACPI table to a binary file. Builds the output
 *              filename from the table signature.
 *
 ******************************************************************************/

int ap_write_to_binary_file(struct acpi_table_header *table, u32 instance)
{
        char filename[ACPI_NAMESEG_SIZE + 16];
        char instance_str[16];
        ACPI_FILE file;
        acpi_size actual;
        u32 table_length;

        /* Obtain table length */

        table_length = ap_get_table_length(table);

        /* Construct lower-case filename from the table local signature */

        if (ACPI_VALIDATE_RSDP_SIG(table->signature)) {
                ACPI_COPY_NAMESEG(filename, ACPI_RSDP_NAME);
        } else {
                ACPI_COPY_NAMESEG(filename, table->signature);
        }

        filename[0] = (char)tolower((int)filename[0]);
        filename[1] = (char)tolower((int)filename[1]);
        filename[2] = (char)tolower((int)filename[2]);
        filename[3] = (char)tolower((int)filename[3]);
        filename[ACPI_NAMESEG_SIZE] = 0;

        /* Handle multiple SSDts - create different filenames for each */

        if (instance > 0) {
                snprintf(instance_str, sizeof(instance_str), "%u", instance);
                strcat(filename, instance_str);
        }

        strcat(filename, FILE_SUFFIX_BINARY_TABLE);

        if (gbl_verbose_mode) {
                fprintf(stderr,
                        "Writing [%4.4s] to binary file: %s 0x%X (%u) bytes\n",
                        table->signature, filename, table->length,
                        table->length);
        }

        /* Open the file and dump the entire table in binary mode */

        file = fopen(filename, "wb");
        if (!file) {
                fprintf(stderr, "Could not open output file: %s\n", filename);
                return (-1);
        }

        actual = fwrite(table, 1, table_length, file);
        if (actual != table_length) {
                fprintf(stderr, "Error writing binary output file: %s\n",
                        filename);
                fclose(file);
                return (-1);
        }

        fclose(file);
        return (0);
}

/******************************************************************************
 *
 * FUNCTION:    ap_get_table_from_file
 *
 * PARAMETERS:  pathname            - File containing the binary ACPI table
 *              out_file_size       - Where the file size is returned
 *
 * RETURN:      Buffer containing the ACPI table. NULL on error.
 *
 * DESCRIPTION: Open a file and read it entirely into a new buffer
 *
 ******************************************************************************/

struct acpi_table_header *ap_get_table_from_file(char *pathname,
                                                 u32 *out_file_size)
{
        struct acpi_table_header *buffer = NULL;
        ACPI_FILE file;
        u32 file_size;
        acpi_size actual;

        /* Must use binary mode */

        file = fopen(pathname, "rb");
        if (!file) {
                fprintf(stderr, "Could not open input file: %s\n", pathname);
                return (NULL);
        }

        /* Need file size to allocate a buffer */

        file_size = cm_get_file_size(file);
        if (file_size == ACPI_UINT32_MAX) {
                fprintf(stderr,
                        "Could not get input file size: %s\n", pathname);
                goto cleanup;
        }

        /* Allocate a buffer for the entire file */

        buffer = ACPI_ALLOCATE_ZEROED(file_size);
        if (!buffer) {
                fprintf(stderr,
                        "Could not allocate file buffer of size: %u\n",
                        file_size);
                goto cleanup;
        }

        /* Read the entire file */

        actual = fread(buffer, 1, file_size, file);
        if (actual != file_size) {
                fprintf(stderr, "Could not read input file: %s\n", pathname);
                ACPI_FREE(buffer);
                buffer = NULL;
                goto cleanup;
        }

        *out_file_size = file_size;

cleanup:
        fclose(file);
        return (buffer);
}