orca/src/platform/posix_io.c

579 lines
13 KiB
C

/************************************************************/ /**
*
* @file: posix_io.c
* @author: Martin Fouilleul
* @date: 25/05/2023
*
*****************************************************************/
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <sys/stat.h>
#include <unistd.h>
#include "platform_io_common.c"
#include "platform_io_internal.c"
oc_file_desc oc_file_desc_nil()
{
return (-1);
}
bool oc_file_desc_is_nil(oc_file_desc fd)
{
return (fd < 0);
}
oc_io_error oc_io_raw_last_error()
{
oc_io_error error = OC_IO_OK;
switch(errno)
{
case EPERM:
case EACCES:
case EROFS:
error = OC_IO_ERR_PERM;
break;
case ENOENT:
error = OC_IO_ERR_NO_ENTRY;
break;
case EINTR:
error = OC_IO_ERR_INTERRUPT;
break;
case EIO:
error = OC_IO_ERR_PHYSICAL;
break;
case ENXIO:
error = OC_IO_ERR_NO_DEVICE;
break;
case EBADF:
// this should only happen when user tries to write/read to a file handle
// opened with readonly/writeonly access
error = OC_IO_ERR_PERM;
break;
case ENOMEM:
error = OC_IO_ERR_MEM;
break;
case EFAULT:
case EINVAL:
case EDOM:
error = OC_IO_ERR_ARG;
break;
case EBUSY:
case EAGAIN:
error = OC_IO_ERR_NOT_READY;
break;
case EEXIST:
error = OC_IO_ERR_EXISTS;
break;
case ENOTDIR:
error = OC_IO_ERR_NOT_DIR;
break;
case EISDIR:
error = OC_IO_ERR_DIR;
break;
case ENFILE:
case EMFILE:
error = OC_IO_ERR_MAX_FILES;
break;
case EFBIG:
error = OC_IO_ERR_FILE_SIZE;
break;
case ENOSPC:
case EDQUOT:
error = OC_IO_ERR_SPACE;
break;
case ELOOP:
error = OC_IO_ERR_MAX_LINKS;
break;
case ENAMETOOLONG:
error = OC_IO_ERR_PATH_LENGTH;
break;
case EOVERFLOW:
error = OC_IO_ERR_OVERFLOW;
break;
default:
error = OC_IO_ERR_UNKNOWN;
break;
}
return (error);
}
static int oc_io_convert_access_rights(oc_file_access rights)
{
int oflags = 0;
if(rights & OC_FILE_ACCESS_READ)
{
if(rights & OC_FILE_ACCESS_WRITE)
{
oflags = O_RDWR;
}
else
{
oflags = O_RDONLY;
}
}
else if(rights & OC_FILE_ACCESS_WRITE)
{
oflags = O_WRONLY;
}
return (oflags);
}
static int oc_io_convert_open_flags(oc_file_open_flags flags)
{
int oflags = 0;
if(flags & OC_FILE_OPEN_TRUNCATE)
{
oflags |= O_TRUNC;
}
if(flags & OC_FILE_OPEN_APPEND)
{
oflags |= O_APPEND;
}
if(flags & OC_FILE_OPEN_CREATE)
{
oflags |= O_CREAT;
}
if(flags & OC_FILE_OPEN_NO_FOLLOW)
{
oflags |= O_NOFOLLOW;
}
if(flags & OC_FILE_OPEN_SYMLINK)
{
oflags |= O_SYMLINK;
}
return (oflags);
}
static int oc_io_update_dir_flags_at(int dirFd, char* path, int flags)
{
struct stat s;
if(!fstatat(dirFd, path, &s, AT_SYMLINK_NOFOLLOW))
{
if((s.st_mode & S_IFMT) == S_IFDIR)
{
if(flags & O_WRONLY)
{
flags &= ~O_WRONLY;
}
else if(flags & O_RDWR)
{
flags &= ~O_RDWR;
flags |= O_RDONLY;
}
}
}
return (flags);
}
oc_file_desc oc_io_raw_open_at(oc_file_desc dirFd, oc_str8 path, oc_file_access accessRights, oc_file_open_flags openFlags)
{
int flags = oc_io_convert_access_rights(accessRights);
flags |= oc_io_convert_open_flags(openFlags);
mode_t mode = S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
| S_IROTH
| S_IWOTH;
oc_arena_scope scratch = oc_scratch_begin();
oc_file_desc fd = -1;
if(dirFd >= 0)
{
if(path.len && path.ptr[0] == '/')
{
//NOTE: if path is absolute, change for a relative one, otherwise openat ignores fd.
oc_str8_list list = { 0 };
oc_str8_list_push(scratch.arena, &list, OC_STR8("."));
oc_str8_list_push(scratch.arena, &list, path);
path = oc_str8_list_join(scratch.arena, list);
}
}
else
{
dirFd = AT_FDCWD;
}
char* pathCStr = oc_str8_to_cstring(scratch.arena, path);
flags = oc_io_update_dir_flags_at(dirFd, pathCStr, flags);
fd = openat(dirFd, pathCStr, flags, mode);
oc_scratch_end(scratch);
return (fd);
}
void oc_io_raw_close(oc_file_desc fd)
{
close(fd);
}
static oc_file_perm oc_io_convert_perm_from_stat(u16 mode)
{
oc_file_perm perm = mode & 07777;
return (perm);
}
static oc_file_type oc_io_convert_type_from_stat(u16 mode)
{
oc_file_type type;
switch(mode & S_IFMT)
{
case S_IFIFO:
type = OC_FILE_FIFO;
break;
case S_IFCHR:
type = OC_FILE_CHARACTER;
break;
case S_IFDIR:
type = OC_FILE_DIRECTORY;
break;
case S_IFBLK:
type = OC_FILE_BLOCK;
break;
case S_IFREG:
type = OC_FILE_REGULAR;
break;
case S_IFLNK:
type = OC_FILE_SYMLINK;
break;
case S_IFSOCK:
type = OC_FILE_SOCKET;
break;
default:
type = OC_FILE_UNKNOWN;
break;
}
return (type);
}
oc_io_error oc_io_raw_fstat(oc_file_desc fd, oc_file_status* status)
{
oc_io_error error = OC_IO_OK;
struct stat s;
if(fstat(fd, &s))
{
error = oc_io_raw_last_error();
}
else
{
status->uid = s.st_ino;
status->perm = oc_io_convert_perm_from_stat(s.st_mode);
status->type = oc_io_convert_type_from_stat(s.st_mode);
status->size = s.st_size;
//TODO: times
}
return (error);
}
oc_io_error oc_io_raw_fstat_at(oc_file_desc dirFd, oc_str8 path, oc_file_open_flags flags, oc_file_status* status)
{
oc_arena_scope scratch = oc_scratch_begin();
if(dirFd >= 0)
{
if(path.len && path.ptr[0] == '/')
{
oc_str8_list list = { 0 };
oc_str8_list_push(scratch.arena, &list, OC_STR8("."));
oc_str8_list_push(scratch.arena, &list, path);
path = oc_str8_list_join(scratch.arena, list);
}
}
else
{
dirFd = AT_FDCWD;
}
char* pathCStr = oc_str8_to_cstring(scratch.arena, path);
int statFlag = (flags & OC_FILE_OPEN_SYMLINK) ? AT_SYMLINK_NOFOLLOW : 0;
oc_io_error error = OC_IO_OK;
struct stat s;
if(fstatat(dirFd, pathCStr, &s, statFlag))
{
error = oc_io_raw_last_error();
}
else
{
status->uid = s.st_ino;
status->perm = oc_io_convert_perm_from_stat(s.st_mode);
status->type = oc_io_convert_type_from_stat(s.st_mode);
status->size = s.st_size;
//TODO: times
}
oc_scratch_end(scratch);
return (error);
}
oc_io_raw_read_link_result oc_io_raw_read_link_at(oc_arena* arena, oc_file_desc dirFd, oc_str8 path)
{
oc_arena_scope scratch = oc_scratch_begin_next(arena);
if(dirFd >= 0)
{
if(path.len && path.ptr[0] == '/')
{
oc_str8_list list = { 0 };
oc_str8_list_push(scratch.arena, &list, OC_STR8("."));
oc_str8_list_push(scratch.arena, &list, path);
path = oc_str8_list_join(scratch.arena, list);
}
}
else
{
dirFd = AT_FDCWD;
}
char* pathCStr = oc_str8_to_cstring(scratch.arena, path);
oc_io_raw_read_link_result result = { 0 };
char buffer[PATH_MAX];
u64 bufferSize = PATH_MAX;
i64 r = readlinkat(dirFd, pathCStr, buffer, bufferSize);
if(r < 0)
{
result.error = oc_io_raw_last_error();
}
else
{
result.target.len = r;
result.target.ptr = oc_arena_push_array(arena, char, result.target.len);
memcpy(result.target.ptr, buffer, result.target.len);
}
oc_scratch_end(scratch);
return (result);
}
bool oc_io_raw_file_exists_at(oc_file_desc dirFd, oc_str8 path, oc_file_open_flags openFlags)
{
oc_arena_scope scratch = oc_scratch_begin();
if(dirFd >= 0)
{
if(path.len && path.ptr[0] == '/')
{
oc_str8_list list = { 0 };
oc_str8_list_push(scratch.arena, &list, OC_STR8("."));
oc_str8_list_push(scratch.arena, &list, path);
path = oc_str8_list_join(scratch.arena, list);
}
}
else
{
dirFd = AT_FDCWD;
}
char* pathCStr = oc_str8_to_cstring(scratch.arena, path);
int flags = (openFlags & OC_FILE_OPEN_SYMLINK) ? AT_SYMLINK_NOFOLLOW : 0;
int r = faccessat(dirFd, pathCStr, F_OK, flags);
bool result = (r == 0);
oc_scratch_end(scratch);
return (result);
}
oc_io_cmp oc_io_close(oc_file_slot* slot, oc_io_req* req, oc_file_table* table)
{
oc_io_cmp cmp = { 0 };
if(slot->fd >= 0)
{
close(slot->fd);
}
oc_file_slot_recycle(table, slot);
return (cmp);
}
oc_io_cmp oc_io_fstat(oc_file_slot* slot, oc_io_req* req)
{
oc_io_cmp cmp = { 0 };
if(req->size < sizeof(oc_file_status))
{
cmp.error = OC_IO_ERR_ARG;
}
else
{
struct stat s;
if(fstat(slot->fd, &s))
{
slot->error = oc_io_raw_last_error();
cmp.error = slot->error;
}
else
{
oc_file_status* status = (oc_file_status*)req->buffer;
status->perm = oc_io_convert_perm_from_stat(s.st_mode);
status->type = oc_io_convert_type_from_stat(s.st_mode);
status->size = s.st_size;
//TODO: times
}
}
return (cmp);
}
oc_io_cmp oc_io_seek(oc_file_slot* slot, oc_io_req* req)
{
oc_io_cmp cmp = { 0 };
int whence;
switch(req->whence)
{
case OC_FILE_SEEK_CURRENT:
whence = SEEK_CUR;
break;
case OC_FILE_SEEK_SET:
whence = SEEK_SET;
break;
case OC_FILE_SEEK_END:
whence = SEEK_END;
}
cmp.result = lseek(slot->fd, req->offset, whence);
if(cmp.result < 0)
{
slot->error = oc_io_raw_last_error();
cmp.error = slot->error;
}
return (cmp);
}
oc_io_cmp oc_io_read(oc_file_slot* slot, oc_io_req* req)
{
oc_io_cmp cmp = { 0 };
cmp.result = read(slot->fd, req->buffer, req->size);
if(cmp.result < 0)
{
slot->error = oc_io_raw_last_error();
cmp.result = 0;
cmp.error = slot->error;
}
return (cmp);
}
oc_io_cmp oc_io_write(oc_file_slot* slot, oc_io_req* req)
{
oc_io_cmp cmp = { 0 };
cmp.result = write(slot->fd, req->buffer, req->size);
if(cmp.result < 0)
{
slot->error = oc_io_raw_last_error();
cmp.result = 0;
cmp.error = slot->error;
}
return (cmp);
}
oc_io_cmp oc_io_get_error(oc_file_slot* slot, oc_io_req* req)
{
oc_io_cmp cmp = { 0 };
cmp.result = slot->error;
return (cmp);
}
oc_io_cmp oc_io_wait_single_req_with_table(oc_io_req* req, oc_file_table* table)
{
oc_io_cmp cmp = { 0 };
oc_file_slot* slot = oc_file_slot_from_handle(table, req->handle);
if(!slot)
{
if(req->op != OC_IO_OPEN_AT)
{
cmp.error = OC_IO_ERR_HANDLE;
}
}
else if(slot->fatal
&& req->op != OC_IO_CLOSE
&& req->op != OC_OC_IO_ERROR)
{
cmp.error = OC_IO_ERR_PREV;
}
if(cmp.error == OC_IO_OK)
{
switch(req->op)
{
case OC_IO_OPEN_AT:
cmp = oc_io_open_at(slot, req, table);
break;
case OC_IO_FSTAT:
cmp = oc_io_fstat(slot, req);
break;
case OC_IO_CLOSE:
cmp = oc_io_close(slot, req, table);
break;
case OC_IO_READ:
cmp = oc_io_read(slot, req);
break;
case OC_IO_WRITE:
cmp = oc_io_write(slot, req);
break;
case OC_IO_SEEK:
cmp = oc_io_seek(slot, req);
break;
case OC_OC_IO_ERROR:
cmp = oc_io_get_error(slot, req);
break;
default:
cmp.error = OC_IO_ERR_OP;
break;
}
}
return (cmp);
}