cosmopolitan/libc/calls/hefty/dirstream.c

245 lines
7.2 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ This program is free software; you can redistribute it and/or modify │
│ it under the terms of the GNU General Public License as published by │
│ the Free Software Foundation; version 2 of the License. │
│ │
│ This program 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 │
│ General Public License for more details. │
│ │
│ You should have received a copy of the GNU General Public License │
│ along with this program; if not, write to the Free Software │
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
│ 02110-1301 USA │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/bits/bits.h"
#include "libc/bits/progn.h"
#include "libc/calls/internal.h"
#include "libc/calls/struct/dirent.h"
#include "libc/dce.h"
#include "libc/mem/mem.h"
#include "libc/nt/enum/fileflagandattributes.h"
#include "libc/nt/enum/filetype.h"
#include "libc/nt/files.h"
#include "libc/nt/runtime.h"
#include "libc/nt/struct/win32finddata.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/dt.h"
#include "libc/sysv/consts/o.h"
#include "libc/sysv/errfuns.h"
struct dirent$freebsd {
uint32_t d_fileno;
uint16_t d_reclen;
uint8_t d_type;
uint8_t d_namlen;
char d_name[256];
};
struct dirstream {
int64_t tell;
int64_t fd;
struct dirent ent;
union {
struct {
unsigned buf_pos;
unsigned buf_end;
char buf[BUFSIZ];
};
struct {
bool isdone;
struct NtWin32FindData windata;
};
};
};
static textwindows noinline DIR *opendir$nt(const char *name) {
int len;
DIR *res;
char16_t name16[PATH_MAX];
if ((len = mkntpath(name, name16)) == -1) return NULL;
if (len + 2 + 1 > PATH_MAX) return PROGN(enametoolong(), NULL);
if (name16[len - 1] == u'/' || name16[len - 1] == u'\\') {
name16[--len] = u'\0';
}
name16[len++] = u'/';
name16[len++] = u'*';
name16[len] = u'\0';
if (!(res = calloc(1, sizeof(DIR)))) return NULL;
if ((res->fd = FindFirstFile(name16, &res->windata)) != -1) {
return res;
} else {
winerr();
free(res);
return NULL;
}
}
static textwindows noinline struct dirent *readdir$nt(DIR *dir) {
if (!dir->isdone) {
memset(&dir->ent, 0, sizeof(dir->ent));
dir->ent.d_ino = 0;
dir->ent.d_off = dir->tell++;
dir->ent.d_reclen = sizeof(dir->ent) +
tprecode16to8(dir->ent.d_name, sizeof(dir->ent.d_name),
dir->windata.cFileName) +
1;
switch (dir->windata.dwFileType) {
case kNtFileTypeDisk:
dir->ent.d_type = DT_BLK;
break;
case kNtFileTypeChar:
dir->ent.d_type = DT_CHR;
break;
case kNtFileTypePipe:
dir->ent.d_type = DT_FIFO;
break;
default:
if (dir->windata.dwFileAttributes & kNtFileAttributeDirectory) {
dir->ent.d_type = DT_DIR;
} else {
dir->ent.d_type = DT_REG;
}
break;
}
dir->isdone = !FindNextFile(dir->fd, &dir->windata);
return &dir->ent;
} else {
return NULL;
}
}
/**
* Opens directory, e.g.
*
* DIR *d;
* struct dirent *e;
* CHECK((d = opendir(path)));
* while ((e = readdir(d))) {
* printf("%s/%s\n", path, e->d_name);
* }
* LOGIFNEG1(closedir(d));
*
* @returns newly allocated DIR object, or NULL w/ errno
* @errors ENOENT, ENOTDIR, EACCES, EMFILE, ENFILE, ENOMEM
* @see glob()
*/
DIR *opendir(const char *name) {
int fd;
DIR *res;
if (!IsWindows() && !IsXnu()) {
res = NULL;
if ((fd = open(name, O_RDONLY | O_DIRECTORY | O_CLOEXEC)) != -1) {
if (!(res = fdopendir(fd))) close(fd);
}
return res;
} else if (IsWindows()) {
return opendir$nt(name);
} else {
enosys(); /* TODO(jart): Implement me! */
return NULL;
}
}
/**
* Creates directory object for file descriptor.
*
* @param fd gets owned by this function, if it succeeds
* @return new directory object, which must be freed by closedir(),
* or NULL w/ errno
* @errors ENOMEM and fd is closed
*/
DIR *fdopendir(int fd) {
DIR *dir;
if (!IsWindows() && !IsXnu()) {
if ((dir = calloc(1, sizeof(*dir)))) {
dir->fd = fd;
return dir;
}
} else {
enosys(); /* TODO(jart): Implement me! */
}
return NULL;
}
/**
* Reads next entry from DIR.
*
* This API doesn't define any particular ordering.
*
* @param dir is the object opendir() or fdopendir() returned
* @return next entry or NULL on end or error, which can be
* differentiated by setting errno to 0 beforehand
*/
struct dirent *readdir(DIR *dir) {
int rc;
struct dirent *ent;
struct dirent$freebsd *freebsd;
if (!IsWindows()) {
if (dir->buf_pos >= dir->buf_end) {
if (!(rc = getdents(dir->fd, dir->buf,
sizeof(dir->buf) - sizeof(dir->ent.d_name))) ||
rc == -1) {
return NULL;
}
dir->buf_pos = 0;
dir->buf_end = rc;
}
if (IsLinux()) {
ent = (struct dirent *)(dir->buf + dir->buf_pos);
dir->buf_pos += ent->d_reclen;
dir->tell = ent->d_off;
} else {
freebsd = (struct dirent$freebsd *)(dir->buf + dir->buf_pos);
dir->buf_pos += freebsd->d_reclen;
ent = &dir->ent;
ent->d_ino = freebsd->d_fileno;
ent->d_off = dir->tell++;
ent->d_reclen = freebsd->d_reclen;
ent->d_type = freebsd->d_type;
memcpy(ent->d_name, freebsd->d_name, freebsd->d_namlen + 1);
}
return ent;
} else {
return readdir$nt(dir);
}
}
/**
* Closes directory object returned by opendir().
* @return 0 on success or -1 w/ errno
*/
int closedir(DIR *dir) {
int rc;
if (dir) {
if (!IsWindows()) {
rc = close(dir->fd);
} else {
rc = FindClose(dir->fd) ? 0 : winerr();
}
free(dir);
} else {
rc = 0;
}
return rc;
}
/**
* Returns offset into directory data.
*/
long telldir(DIR *dir) {
return dir->tell;
}
/**
* Returns file descriptor associated with DIR object.
*/
int dirfd(DIR *dir) {
return dir->fd;
}