/*

  zip_source_file_stdio.c -- read-only stdio file source implementation

  Copyright (C) 2020-2023 Dieter Baron and Thomas Klausner

  This file is part of libzip, a library to manipulate ZIP archives.

  The authors can be contacted at <info@libzip.org>

  Redistribution and use in source and binary forms, with or without

  modification, are permitted provided that the following conditions

  are met:

  1. Redistributions of source code must retain the above copyright

     notice, this list of conditions and the following disclaimer.

  2. Redistributions in binary form must reproduce the above copyright

     notice, this list of conditions and the following disclaimer in

     the documentation and/or other materials provided with the

     distribution.

  3. The names of the authors may not be used to endorse or promote

     products derived from this software without specific prior

     written permission.

  THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS

  OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

  ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY

  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE

  GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER

  IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR

  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN

  IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

*/

#include "zipint.h"

#include "zip_source_file.h"

#include "zip_source_file_stdio.h"

#include <fcntl.h>

#include <stdio.h>

#include <stdlib.h>

#ifdef _WIN32

#ifndef S_IWUSR

#define S_IWUSR _S_IWRITE

#endif

#endif

/* clang-format off */

static zip_source_file_operations_t ops_stdio_read = {

    _zip_stdio_op_close,

    NULL,

    NULL,

    NULL,

    NULL,

    _zip_stdio_op_read,

    NULL,

    NULL,

    _zip_stdio_op_seek,

    _zip_stdio_op_stat,

    NULL,

    _zip_stdio_op_tell,

    NULL

};

/* clang-format on */

ZIP_EXTERN zip_source_t *

zip_source_filep(zip_t *za, FILE *file, zip_uint64_t start, zip_int64_t len) {

    if (za == NULL) {

        return NULL;

    }

    return zip_source_filep_create(file, start, len, &za->error);

}

ZIP_EXTERN zip_source_t *

zip_source_filep_create(FILE *file, zip_uint64_t start, zip_int64_t length, zip_error_t *error) {

    if (file == NULL || length < ZIP_LENGTH_UNCHECKED) {

        zip_error_set(error, ZIP_ER_INVAL, 0);

        return NULL;

    }

    return zip_source_file_common_new(NULL, file, start, length, NULL, &ops_stdio_read, NULL, error);

}

void

_zip_stdio_op_close(zip_source_file_context_t *ctx) {

    fclose((FILE *)ctx->f);

}

zip_int64_t

_zip_stdio_op_read(zip_source_file_context_t *ctx, void *buf, zip_uint64_t len) {

    size_t i;

#if SIZE_MAX < ZIP_UINT64_MAX

    if (len > SIZE_MAX) {

        len = SIZE_MAX;

    }

#endif

    if ((i = fread(buf, 1, (size_t)len, ctx->f)) == 0) {

        if (ferror((FILE *)ctx->f)) {

            zip_error_set(&ctx->error, ZIP_ER_READ, errno);

            return -1;

        }

    }

    return (zip_int64_t)i;

}

bool

_zip_stdio_op_seek(zip_source_file_context_t *ctx, void *f, zip_int64_t offset, int whence) {

#if ZIP_FSEEK_MAX > ZIP_INT64_MAX

    if (offset > ZIP_FSEEK_MAX || offset < ZIP_FSEEK_MIN) {

        zip_error_set(&ctx->error, ZIP_ER_SEEK, EOVERFLOW);

        return false;

    }

#endif

    if (zip_os_fseek((FILE *)f, (zip_off_t)offset, whence) < 0) {

        zip_error_set(&ctx->error, ZIP_ER_SEEK, errno);

        return false;

    }

    return true;

}

bool

_zip_stdio_op_stat(zip_source_file_context_t *ctx, zip_source_file_stat_t *st) {

    zip_os_stat_t sb;

    int ret;

    if (ctx->fname) {

        ret = zip_os_stat(ctx->fname, &sb);

    }

    else {

        ret = zip_os_fstat(fileno((FILE *)ctx->f), &sb);

    }

    if (ret < 0) {

        if (errno == ENOENT) {

            st->exists = false;

            return true;

        }

        zip_error_set(&ctx->error, ZIP_ER_READ, errno);

        return false;

    }

    st->size = (zip_uint64_t)sb.st_size;

    st->mtime = sb.st_mtime;

    st->regular_file = S_ISREG(sb.st_mode);

    st->exists = true;

    /* We're using UNIX file API, even on Windows; thus, we supply external file attributes with Unix values. */

    /* TODO: This could be improved on Windows by providing Windows-specific file attributes */

    ctx->attributes.valid = ZIP_FILE_ATTRIBUTES_HOST_SYSTEM | ZIP_FILE_ATTRIBUTES_EXTERNAL_FILE_ATTRIBUTES;

    ctx->attributes.host_system = ZIP_OPSYS_UNIX;

    ctx->attributes.external_file_attributes = (((zip_uint32_t)sb.st_mode) << 16) | ((sb.st_mode & S_IWUSR) ? 0 : 1);

    return true;

}

zip_int64_t

_zip_stdio_op_tell(zip_source_file_context_t *ctx, void *f) {

    zip_off_t offset = zip_os_ftell((FILE *)f);

    if (offset < 0) {

        zip_error_set(&ctx->error, ZIP_ER_SEEK, errno);

    }

    return offset;

}