/* Copyright (C) 2014 Stony Brook University
This file is part of Graphene Library OS.
Graphene Library OS is free software: you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public License
as published by the Free Software Foundation, either version 3 of the
License, or (at your option) any later version.
Graphene Library OS is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program. If not, see . */
/*
* db_files.c
*
* This file contains operands to handle streams with URIs that start with
* "file:" or "dir:".
*/
#include "pal_defs.h"
#include "pal_linux_defs.h"
#include "pal.h"
#include "pal_internal.h"
#include "pal_linux.h"
#include "pal_linux_error.h"
#include "pal_debug.h"
#include "pal_error.h"
#include "api.h"
#include
typedef __kernel_pid_t pid_t;
#undef __GLIBC__
#include
#include
/* 'open' operation for file streams */
static int file_open (PAL_HANDLE * handle, const char * type, const char * uri,
int access, int share, int create, int options)
{
if (strcmp_static(type, URI_TYPE_FILE))
return -PAL_ERROR_INVAL;
/* try to do the real open */
int ret = INLINE_SYSCALL(open, 3, uri,
HOST_ACCESS(access)|create|options|O_CLOEXEC,
share);
if (IS_ERR(ret))
return unix_to_pal_error(ERRNO(ret));
/* if try_create_path succeeded, prepare for the file handle */
size_t len = strlen(uri);
PAL_HANDLE hdl = malloc(HANDLE_SIZE(file) + len + 1);
SET_HANDLE_TYPE(hdl, file);
HANDLE_HDR(hdl)->flags |= RFD(0)|WFD(0);
hdl->file.fd = ret;
hdl->file.map_start = NULL;
char * path = (void *) hdl + HANDLE_SIZE(file);
memcpy(path, uri, len + 1);
hdl->file.realpath = (PAL_STR) path;
*handle = hdl;
return 0;
}
/* 'read' operation for file streams. */
static int64_t file_read (PAL_HANDLE handle, uint64_t offset, uint64_t count,
void * buffer)
{
int fd = handle->file.fd;
int64_t ret;
ret = INLINE_SYSCALL(pread64, 4, fd, buffer, count, offset);
if (IS_ERR(ret))
return unix_to_pal_error(ERRNO(ret));
return ret;
}
/* 'write' operation for file streams. */
static int64_t file_write (PAL_HANDLE handle, uint64_t offset, uint64_t count,
const void * buffer)
{
int fd = handle->file.fd;
int64_t ret;
ret = INLINE_SYSCALL(pwrite64, 4, fd, buffer, count, offset);
if (IS_ERR(ret))
return unix_to_pal_error(ERRNO(ret));
return ret;
}
/* 'close' operation for file streams. In this case, it will only
close the file withou deleting it. */
static int file_close (PAL_HANDLE handle)
{
int fd = handle->file.fd;
int ret = INLINE_SYSCALL(close, 1, fd);
/* initial realpath is part of handle object and will be freed with it */
if (handle->file.realpath &&
handle->file.realpath != (void *) handle + HANDLE_SIZE(file)) {
free((void *) handle->file.realpath);
}
return IS_ERR(ret) ? unix_to_pal_error(ERRNO(ret)) : 0;
}
/* 'delete' operation for file streams. It will actually delete
the file if we can successfully close it. */
static int file_delete (PAL_HANDLE handle, int access)
{
if (access)
return -PAL_ERROR_INVAL;
INLINE_SYSCALL(unlink, 1, handle->file.realpath);
return 0;
}
/* 'map' operation for file stream. */
static int file_map (PAL_HANDLE handle, void ** addr, int prot,
uint64_t offset, uint64_t size)
{
int fd = handle->file.fd;
void * mem = *addr;
/*
* work around for fork emulation
* the first exec image to be loaded has to be at same address
* as parent.
*/
if (mem == NULL && handle->file.map_start != NULL) {
mem = (PAL_PTR)handle->file.map_start;
/* this address is used. don't over-map it later */
handle->file.map_start = NULL;
}
int flags = MAP_FILE|HOST_FLAGS(0, prot)|(mem ? MAP_FIXED : 0);
prot = HOST_PROT(prot);
/* The memory will always allocated with flag MAP_PRIVATE
and MAP_FILE */
mem = (void *) ARCH_MMAP(mem, size, prot, flags, fd, offset);
if (IS_ERR_P(mem))
return -PAL_ERROR_DENIED;
*addr = mem;
return 0;
}
/* 'setlength' operation for file stream. */
static int64_t file_setlength (PAL_HANDLE handle, uint64_t length)
{
int ret = INLINE_SYSCALL(ftruncate, 2, handle->file.fd, length);
if (IS_ERR(ret))
return (ERRNO(ret) == EINVAL || ERRNO(ret) == EBADF) ?
-PAL_ERROR_BADHANDLE : -PAL_ERROR_DENIED;
return (int64_t) length;
}
/* 'flush' operation for file stream. */
static int file_flush (PAL_HANDLE handle)
{
int ret = INLINE_SYSCALL(fsync, 1, handle->file.fd);
if (IS_ERR(ret))
return (ERRNO(ret) == EINVAL || ERRNO(ret) == EBADF) ?
-PAL_ERROR_BADHANDLE : -PAL_ERROR_DENIED;
return 0;
}
static inline int file_stat_type (struct stat * stat)
{
if (S_ISREG(stat->st_mode))
return pal_type_file;
if (S_ISDIR(stat->st_mode))
return pal_type_dir;
if (S_ISCHR(stat->st_mode))
return pal_type_dev;
if (S_ISFIFO(stat->st_mode))
return pal_type_pipe;
if (S_ISSOCK(stat->st_mode))
return pal_type_dev;
return 0;
}
/* copy attr content from POSIX stat struct to PAL_STREAM_ATTR */
static inline void
file_attrcopy (PAL_STREAM_ATTR * attr, struct stat * stat)
{
attr->handle_type = file_stat_type(stat);
attr->disconnected = PAL_FALSE;
attr->nonblocking = PAL_FALSE;
attr->readable = stataccess(stat, ACCESS_R);
attr->writable = stataccess(stat, ACCESS_W);
attr->runnable = stataccess(stat, ACCESS_X);
attr->share_flags = stat->st_mode;
attr->pending_size = stat->st_size;
}
/* 'attrquery' operation for file streams */
static int file_attrquery (const char * type, const char * uri,
PAL_STREAM_ATTR * attr)
{
if (strcmp_static(type, URI_TYPE_FILE) && strcmp_static(type, URI_TYPE_DIR))
return -PAL_ERROR_INVAL;
struct stat stat_buf;
/* try to do the real open */
int ret = INLINE_SYSCALL(stat, 2, uri, &stat_buf);
/* if it failed, return the right error code */
if (IS_ERR(ret))
return unix_to_pal_error(ERRNO(ret));
file_attrcopy(attr, &stat_buf);
return 0;
}
/* 'attrquerybyhdl' operation for file streams */
static int file_attrquerybyhdl (PAL_HANDLE handle,
PAL_STREAM_ATTR * attr)
{
int fd = handle->generic.fds[0];
struct stat stat_buf;
int ret = INLINE_SYSCALL(fstat, 2, fd, &stat_buf);
if (IS_ERR(ret))
return unix_to_pal_error(ERRNO(ret));
file_attrcopy(attr, &stat_buf);
return 0;
}
static int file_attrsetbyhdl (PAL_HANDLE handle,
PAL_STREAM_ATTR * attr)
{
int fd = handle->generic.fds[0], ret;
ret = INLINE_SYSCALL(fchmod, 2, fd, attr->share_flags | 0600);
if (IS_ERR(ret))
return unix_to_pal_error(ERRNO(ret));
return 0;
}
static int file_rename (PAL_HANDLE handle, const char * type,
const char * uri)
{
if (strcmp_static(type, URI_TYPE_FILE))
return -PAL_ERROR_INVAL;
char* tmp = strdup(uri);
if (!tmp)
return -PAL_ERROR_NOMEM;
int ret = INLINE_SYSCALL(rename, 2, handle->file.realpath, uri);
if (IS_ERR(ret)) {
free(tmp);
return unix_to_pal_error(ERRNO(ret));
}
/* initial realpath is part of handle object and will be freed with it */
if (handle->file.realpath &&
handle->file.realpath != (void *) handle + HANDLE_SIZE(file)) {
free((void *) handle->file.realpath);
}
handle->file.realpath = tmp;
return 0;
}
static int file_getname (PAL_HANDLE handle, char * buffer, size_t count)
{
if (!handle->file.realpath)
return 0;
size_t len = strlen(handle->file.realpath);
char * tmp = strcpy_static(buffer, URI_PREFIX_FILE, count);
if (!tmp || buffer + count < tmp + len + 1)
return -PAL_ERROR_TOOLONG;
memcpy(tmp, handle->file.realpath, len + 1);
return tmp + len - buffer;
}
const char * file_getrealpath (PAL_HANDLE handle)
{
return handle->file.realpath;
}
struct handle_ops file_ops = {
.getname = &file_getname,
.getrealpath = &file_getrealpath,
.open = &file_open,
.read = &file_read,
.write = &file_write,
.close = &file_close,
.delete = &file_delete,
.map = &file_map,
.setlength = &file_setlength,
.flush = &file_flush,
.attrquery = &file_attrquery,
.attrquerybyhdl = &file_attrquerybyhdl,
.attrsetbyhdl = &file_attrsetbyhdl,
.rename = &file_rename,
};
/* 'open' operation for directory stream. Directory stream does not have a
specific type prefix, its URI looks the same file streams, plus it
ended with slashes. dir_open will be called by file_open. */
static int dir_open (PAL_HANDLE * handle, const char * type, const char * uri,
int access, int share, int create, int options)
{
if (strcmp_static(type, URI_TYPE_DIR))
return -PAL_ERROR_INVAL;
if (!WITHIN_MASK(access, PAL_ACCESS_MASK))
return -PAL_ERROR_INVAL;
int ret = 0;
if (create & PAL_CREATE_TRY) {
ret = INLINE_SYSCALL(mkdir, 2, uri, share);
if (IS_ERR(ret) && ERRNO(ret) == EEXIST &&
create & PAL_CREATE_ALWAYS)
return -PAL_ERROR_STREAMEXIST;
}
ret = INLINE_SYSCALL(open, 3, uri, O_DIRECTORY|options|O_CLOEXEC, 0);
if (IS_ERR(ret))
return unix_to_pal_error(ERRNO(ret));
size_t len = strlen(uri);
PAL_HANDLE hdl = malloc(HANDLE_SIZE(dir) + len + 1);
SET_HANDLE_TYPE(hdl, dir);
HANDLE_HDR(hdl)->flags |= RFD(0);
hdl->dir.fd = ret;
char * path = (void *) hdl + HANDLE_SIZE(dir);
memcpy(path, uri, len + 1);
hdl->dir.realpath = (PAL_STR) path;
hdl->dir.buf = (PAL_PTR) NULL;
hdl->dir.ptr = (PAL_PTR) NULL;
hdl->dir.end = (PAL_PTR) NULL;
hdl->dir.endofstream = PAL_FALSE;
*handle = hdl;
return 0;
}
struct linux_dirent64 {
unsigned long d_ino;
unsigned long d_off;
unsigned short d_reclen;
unsigned char d_type;
char d_name[];
};
#define DT_UNKNOWN 0
#define DT_FIFO 1
#define DT_CHR 2
#define DT_DIR 4
#define DT_BLK 6
#define DT_REG 8
#define DT_LNK 10
#define DT_SOCK 12
#define DT_WHT 14
#define DIRBUF_SIZE 1024
static inline bool is_dot_or_dotdot(const char* name) {
return (name[0] == '.' && !name[1]) || (name[0] == '.' && name[1] == '.' && !name[2]);
}
/* 'read' operation for directory stream. Directory stream will not
need a 'write' operation. */
static int64_t dir_read(PAL_HANDLE handle, uint64_t offset, size_t count, void* _buf) {
size_t bytes_written = 0;
char* buf = (char*)_buf;
if (offset) {
return -PAL_ERROR_INVAL;
}
if (handle->dir.endofstream == PAL_TRUE) {
return -PAL_ERROR_ENDOFSTREAM;
}
while (1) {
while ((char*)handle->dir.ptr < (char*)handle->dir.end) {
struct linux_dirent64* dirent = (struct linux_dirent64*)handle->dir.ptr;
if (is_dot_or_dotdot(dirent->d_name)) {
goto skip;
}
bool is_dir = dirent->d_type == DT_DIR;
size_t len = strlen(dirent->d_name);
if (len + 1 + (is_dir ? 1 : 0) > count) {
goto out;
}
memcpy(buf, dirent->d_name, len);
if (is_dir) {
buf[len++] = '/';
}
buf[len++] = '\0';
buf += len;
bytes_written += len;
count -= len;
skip:
handle->dir.ptr = (char*)handle->dir.ptr + dirent->d_reclen;
}
if (!count) {
/* No space left, returning */
goto out;
}
if (!handle->dir.buf) {
handle->dir.buf = (PAL_PTR)malloc(DIRBUF_SIZE);
if (!handle->dir.buf) {
return -PAL_ERROR_NOMEM;
}
}
int size = INLINE_SYSCALL(getdents64, 3, handle->dir.fd, handle->dir.buf, DIRBUF_SIZE);
if (IS_ERR(size)) {
/* If something was written just return that and pretend
* no error was seen - it will be caught next time. */
if (bytes_written) {
return bytes_written;
}
return unix_to_pal_error(ERRNO(size));
}
if (!size) {
handle->dir.endofstream = PAL_TRUE;
goto out;
}
handle->dir.ptr = handle->dir.buf;
handle->dir.end = (char*)handle->dir.buf + size;
}
out:
return (int64_t)bytes_written ? : -PAL_ERROR_ENDOFSTREAM;
}
/* 'close' operation of directory streams */
static int dir_close (PAL_HANDLE handle)
{
int fd = handle->dir.fd;
int ret = INLINE_SYSCALL(close, 1, fd);
if (handle->dir.buf) {
free((void *) handle->dir.buf);
handle->dir.buf = handle->dir.ptr = handle->dir.end = (PAL_PTR) NULL;
}
/* initial realpath is part of handle object and will be freed with it */
if (handle->dir.realpath &&
handle->dir.realpath != (void *) handle + HANDLE_SIZE(dir)) {
free((void *) handle->dir.realpath);
}
if (IS_ERR(ret))
return -PAL_ERROR_BADHANDLE;
return 0;
}
/* 'delete' operation of directoy streams */
static int dir_delete (PAL_HANDLE handle, int access)
{
if (access)
return -PAL_ERROR_INVAL;
int ret = dir_close(handle);
if (ret < 0)
return ret;
ret = INLINE_SYSCALL(rmdir, 1, handle->dir.realpath);
return (IS_ERR(ret) && ERRNO(ret) != ENOENT) ?
-PAL_ERROR_DENIED : 0;
}
static int dir_rename (PAL_HANDLE handle, const char * type,
const char * uri)
{
if (strcmp_static(type, URI_TYPE_DIR))
return -PAL_ERROR_INVAL;
char* tmp = strdup(uri);
if (!tmp)
return -PAL_ERROR_NOMEM;
int ret = INLINE_SYSCALL(rename, 2, handle->dir.realpath, uri);
if (IS_ERR(ret)) {
free(tmp);
return unix_to_pal_error(ERRNO(ret));
}
/* initial realpath is part of handle object and will be freed with it */
if (handle->dir.realpath &&
handle->dir.realpath != (void *) handle + HANDLE_SIZE(dir)) {
free((void *) handle->dir.realpath);
}
handle->dir.realpath = tmp;
return 0;
}
static int dir_getname (PAL_HANDLE handle, char * buffer, size_t count)
{
if (!handle->dir.realpath)
return 0;
size_t len = strlen(handle->dir.realpath);
char * tmp = strcpy_static(buffer, URI_PREFIX_DIR, count);
if (!tmp || buffer + count < tmp + len + 1)
return -PAL_ERROR_TOOLONG;
memcpy(tmp, handle->dir.realpath, len + 1);
return tmp + len - buffer;
}
static const char * dir_getrealpath (PAL_HANDLE handle)
{
return handle->dir.realpath;
}
struct handle_ops dir_ops = {
.getname = &dir_getname,
.getrealpath = &dir_getrealpath,
.open = &dir_open,
.read = &dir_read,
.close = &dir_close,
.delete = &dir_delete,
.attrquery = &file_attrquery,
.attrquerybyhdl = &file_attrquerybyhdl,
.attrsetbyhdl = &file_attrsetbyhdl,
.rename = &dir_rename,
};