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// SPDX-License-Identifier: LGPL-3.0-or-later
#include "sys/sys_local.h"
#include "sys/fs.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <libgen.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
Fildes Sys_Fopen(const char *path, FopenMode mode, unsigned flags)
{
Fildes fd;
errno = 0;
// Open file
switch (mode) {
case FM_READ:
fd = open(path, O_RDONLY);
break;
case FM_WRITE:
fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0666);
break;
case FM_APPEND:
fd = open(path, O_WRONLY | O_CREAT | O_APPEND, 0666);
break;
case FM_EXCL:
fd = open(path, O_WRONLY | O_CREAT | O_EXCL, 0666);
break;
case FM_TEMP: {
#ifdef __linux__
// Linux supports O_TMPFILE for safer temporary file creation
fd = open(path, O_WRONLY | O_EXCL | O_TMPFILE, 0600);
if (fd >= 0)
break; // success
if (errno == ENOENT || errno == ENOTDIR || errno == EISDIR)
break; // file not found - don't fallback
if (errno != EOPNOTSUPP)
break; // error - don't fallback
// Fallback to regular mkstemp()
#endif
size_t n = strlen(path);
char *buf = (char *) alloca(n + 1 + 6 + 1);
if (sprintf(buf, "%s/XXXXXX", path) < 0) {
Sys_SetErrStat(errno, "sprintf() failed");
return FILDES_BAD;
}
fd = mkstemp(buf);
break;
}
default:
Sys_SetErrStat(EINVAL, "Bad value for 'mode'");
return FILDES_BAD;
}
if (errno == ENOENT || errno == ENOTDIR || errno == EISDIR)
errno = 0; // file not found - not an error
Sys_SetErrStat(errno, "open()/mkstemp()");
// Apply hints (if possible)
#ifdef __linux__
if (fd >= 0) {
if (flags & FH_SEQ)
posix_fadvise(fd, 0, 0, POSIX_FADV_SEQUENTIAL);
if (flags & FH_RAND)
posix_fadvise(fd, 0, 0, POSIX_FADV_RANDOM);
if (flags & FH_NOREUSE)
posix_fadvise(fd, 0, 0, POSIX_FADV_NOREUSE);
}
#endif
USED(flags);
return fd;
}
Sint64 Sys_Fread(Fildes fd, void *buf, size_t nbytes)
{
Sint64 n;
errno = 0;
n = read(fd, buf, nbytes);
Sys_SetErrStat(errno, "read()");
return n;
}
Sint64 Sys_Fwrite(Fildes fd, const void *buf, size_t nbytes)
{
Sint64 n;
errno = 0;
n = write(fd, buf, nbytes);
Sys_SetErrStat(errno, "write() failed");
return n;
}
Sint64 Sys_Ftell(Fildes fd)
{
Sint64 pos;
errno = 0;
pos = lseek(fd, 0, SEEK_CUR);
if (pos < 0 && errno != ESPIPE)
errno = 0; // lseek() unsupported, but not a system error
Sys_SetErrStat(errno, "lseek()");
return pos;
}
Sint64 Sys_Fseek(Fildes fd, Sint64 off, SeekMode whence)
{
Sint64 pos;
int mode;
switch (whence) {
case SK_SET: mode = SEEK_SET; break;
case SK_CUR: mode = SEEK_CUR; break;
case SK_END: mode = SEEK_END; break;
default:
Sys_SetErrStat(EINVAL, "Bad value for 'whence'");
return -1;
}
errno = 0;
pos = lseek(fd, off, mode);
if (pos < 0 && errno == ESPIPE)
errno = 0; // lseek() unsupported, but not a system error
Sys_SetErrStat(errno, "lseek()");
return pos;
}
Sint64 Sys_FileSize(Fildes fd)
{
Sint64 size = -1;
struct stat buf;
errno = 0;
if (fstat(fd, &buf) == 0)
size = buf.st_size;
Sys_SetErrStat(errno, "fstat()");
return size;
}
Judgement Sys_SetEof(Fildes fd)
{
Sint64 pos = Sys_Ftell(fd);
if (pos < 0)
return NG; // Sys_Ftell() already sets error
ftruncate(fd, pos);
return Sys_SetErrStat(errno, "ftruncate()");
}
Judgement Sys_Fsync(Fildes fd, Boolean fullSync)
{
errno = 0;
#ifdef __linux__
// Take advantage of fdatasync() if possible
if (fullSync)
fsync(fd);
else
fdatasync(fd);
#else
// Play it safe and portable
USED(fullSync);
fsync(fd);
#endif
return Sys_SetErrStat(errno, "fsync()/fdatasync()");
}
void Sys_Fclose(Fildes fd)
{
errno = 0;
close(fd);
Sys_SetErrStat(errno, "close()");
}
typedef struct FileList FileList;
struct FileList {
FileList *next;
size_t len;
char name[1]; // dynamically sized, len+1
};
#ifdef _DIRENT_HAVE_D_TYPE
// May save some syscalls
#define ISUNK(ent) ((ent)->d_type == DT_UNKNOWN)
#define ISDIR(ent) ((ent)->d_type == DT_DIR)
#define ISLNK(ent) ((ent)->d_type == DT_LNK)
#else
// ...as if DT_UNKNOWN is always set
#define ISUNK(ent) (1)
#define ISDIR(ent) (0)
#define ISLNK(ent) (0)
#endif
char **Sys_ListFiles(const char *path, unsigned *nfiles, const char *pat)
{
DIR *dir = opendir(path);
if (!dir) {
if (errno != ENOENT && errno != ENOTDIR)
Sys_SetErrStat(errno, "opendir()");
if (nfiles)
*nfiles = 0;
return NULL;
}
if (!pat)
pat = "";
Boolean dirOnly = (strcmp(pat, "/") == 0);
size_t elen = strlen(pat);
// Scan directory
FileList *entries = NULL;
unsigned count = 0;
size_t nchars = 0;
struct stat st;
struct dirent *ent;
char **files;
char *namep;
errno = 0;
while ((ent = readdir(dir)) != NULL) {
// Skip special entries
if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0)
continue;
size_t len = strlen(ent->d_name);
if (dirOnly) {
// Filter anything other than subdirectories
Boolean isDir;
if (ISUNK(ent) || ISLNK(ent)) {
// Need a full stat() on entry
if (fstatat(dirfd(dir), ent->d_name, &st, 0) != 0) {
Sys_SetErrStat(errno, "fstatat()");
goto fail;
}
isDir = S_ISDIR(st.st_mode);
} else {
// May take advantage of dirent's d_type
isDir = ISDIR(ent);
}
if (!isDir)
continue;
} else {
// Filter by extension pattern
if (elen >= len)
continue;
if (strcmp(ent->d_name + len - elen, pat) != 0)
continue;
}
// Update counters
count++;
nchars += len + 1;
// ...and remember this entry
FileList *e = (FileList *) alloca(sizeof(*e) + len); // includes '\0'
e->next = entries;
e->len = len;
memcpy(e->name, ent->d_name, len + 1);
entries = e;
}
if (errno != 0) {
Sys_SetErrStat(errno, "readdir()");
goto fail;
}
// Allocate result, single malloc(), +1 for NULL sentinel
files = (char **) malloc(sizeof(*files) * (count + 1) + nchars);
if (!files) {
Sys_OutOfMemory();
goto fail;
}
closedir(dir); // safe, can't fail anymore
// Collect files in buffer
namep = (char *) (files + count + 1);
for (unsigned i = 0; i < count; i++) {
files[i] = namep;
size_t n = entries->len + 1;
memcpy(namep, entries->name, n);
namep += n;
entries = entries->next;
}
files[count] = NULL; // NULL-terminate the file list
if (nfiles)
*nfiles = count;
return files;
fail:
closedir(dir);
if (nfiles)
*nfiles = 0;
return NULL;
}
Judgement Sys_Mkdir(const char *path)
{
errno = 0;
if (mkdir(path, 0755) != 0) {
int err = errno; // save errno - avoid overriding by stat()
if (err == EEXIST) {
// Make sure this is actually a directory
struct stat buf;
if (stat(path, &buf) == 0 && S_ISDIR(buf.st_mode))
err = 0; // all good
}
errno = err;
}
return Sys_SetErrStat(errno, "mkdir()");
}
Judgement Sys_Rename(const char *path, const char *new_path)
{
errno = 0;
rename(path, new_path);
return Sys_SetErrStat(errno, "rename()");
}
Judgement Sys_Remove(const char *path)
{
errno = 0;
remove(path);
// TODO check not found
return Sys_SetErrStat(errno, "remove()");
}