src/server/plugins/postgresql/vfs.h

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2022 Olaf Wintermann. All rights reserved.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT HOLDER OR CONTRIBUTORS 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.
 */

#ifndef WS_PG_VFS_H
#define WS_PG_VFS_H

#include "../../public/nsapi.h"
#include "../../public/vfs.h"

#include "config.h"

#include <libpq-fe.h>
#include <libpq/libpq-fs.h>

#ifdef __cplusplus
extern "C" {
#endif

#define PG_ETAG_MAXLEN 48
    
typedef struct PgVFS {
    ResourceData *pg_resource;
    PGconn *connection;
    char root_resource_id_str[32];
    int64_t root_resource_id;
} PgVFS;

typedef struct PgFile {
    int64_t      resource_id;
    int64_t      parent_id;
    WSBool       iscollection;
    Oid          oid;
    int          fd;
    int          oflags;
    char         etag[PG_ETAG_MAXLEN];
    struct stat  s;
} PgFile;

typedef struct PgDir {
    VFSFile      *file;
    PGresult     *result;
    int          row;
    int          nrows;
} PgDir;

void* pg_vfs_init(ServerConfiguration *cfg, pool_handle_t *pool, WSConfigNode *config);

VFS* pg_vfs_create(Session *sn, Request *rq, pblock *pb, void *initData);

VFS* pg_vfs_create_from_resourcedata(Session *sn, Request *rq, PgRepository *repo, ResourceData *resdata);


/*
 * Resolve a path into a parent_id and resource name
 * 
 * Only absolute paths are supported, therefore path[0] must be '/'
 * 
 * If the resource is not found, res_errno is set to ENOENT
 */
int pg_resolve_path(
        PGconn *connection,
        const char *path,
        const char *root_id,
        int64_t *parent_id,
        int64_t *resource_id,
        Oid *oid,
        const char **resource_name,
        WSBool *iscollection,
        struct stat *s,
        char *etag,
        int *res_errno);

void pg_set_stat(
        struct stat *s,
        const char *iscollection,
        const char *lastmodified,
        const char *creationdate,
        const char *contentlength);

int pg_create_file(
        VFSContext *ctx,
        PgVFS *pg,
        const char *path,
        int64_t *new_resource_id,
        int64_t *res_parent_id,
        Oid *oid,
        const char **resource_name,
        struct stat *s,
        WSBool collection);

int pg_remove_res(
        VFSContext *ctx,
        PgVFS *pg,
        int64_t resource_id,
        Oid oid);

int pg_update_resource(PgVFS *pg, int64_t resource_id, int64_t contentlength);
    
SYS_FILE pg_vfs_open(VFSContext *ctx, const char *path, int oflags);
int pg_vfs_stat(VFSContext *ctx, const char *path, struct stat *buf);
int pg_vfs_fstat(VFSContext *ctx, SYS_FILE fd, struct stat *buf);
VFS_DIR pg_vfs_opendir(VFSContext *ctx, const char *path);
VFS_DIR pg_vfs_fdopendir(VFSContext *ctx, SYS_FILE fd);
int pg_vfs_mkdir(VFSContext *ctx, const char *path);
int pg_vfs_unlink(VFSContext *ctx, const char *path);
int pg_vfs_rmdir(VFSContext *ctx, const char *path);

    
ssize_t pg_vfs_io_read(SYS_FILE fd, void *buf, size_t nbyte);
ssize_t pg_vfs_io_write(SYS_FILE fd, const void *buf, size_t nbyte);
ssize_t pg_vfs_io_pread(SYS_FILE fd, void *buf, size_t nbyte, off_t offset);
ssize_t pg_vfs_io_pwrite(SYS_FILE fd, const void *buf, size_t nbyte, off_t offset);
off_t pg_vfs_io_seek(SYS_FILE fd, off_t offset, int whence);
off_t pg_vfs_io_tell(SYS_FILE fd);
void pg_vfs_io_close(SYS_FILE fd);
const char *pg_vfs_io_getetag(SYS_FILE fd);


int pg_vfs_dirio_readdir(VFS_DIR dir, VFS_ENTRY *entry, int getstat);
void pg_vfs_dirio_close(VFS_DIR dir);

time_t pg_convert_timestamp(const char *timestamp);
int pg_convert_timestamp_tm(const char *timestamp, struct tm *tm);

#ifdef __cplusplus
}
#endif

#endif /* WS_PG_VFS_H */