zig/lib/libc/mingw/stdio/ftruncate64.c

372 lines
9.2 KiB
C

#ifdef TEST_FTRUNCATE64
#include <fcntl.h>
#include <sys/stat.h>
#endif /* TEST_FTRUNCATE64 */
#include <stdio.h>
#include <unistd.h>
#include <io.h>
#include <stdlib.h>
#include <errno.h>
#include <wchar.h>
#include <windows.h>
#include <psapi.h>
/* Mutually exclusive methods
We check disk space as truncating more than the allowed space results
in file getting mysteriously deleted
*/
#define _CHECK_SPACE_BY_VOLUME_METHOD_ 1 /* Needs to walk through all volumes */
#define _CHECK_SPACE_BY_PSAPI_METHOD_ 0 /* Requires psapi.dll */
#define _CHECK_SPACE_BY_VISTA_METHOD_ 0 /* Won't work on XP */
#if (_CHECK_SPACE_BY_PSAPI_METHOD_ == 1) /* Retrive actual volume path */
static LPWSTR getdirpath(const LPWSTR __str){
int len, walk = 0;
LPWSTR dirname;
while (__str[walk] != L'\0'){
walk++;
if (__str[walk] == L'\\') len = walk + 1;
}
dirname = calloc(len + 1, sizeof(wchar_t));
if (!dirname) return dirname; /* memory error */
return wcsncpy(dirname,__str,len);
}
static LPWSTR xp_normalize_fn(const LPWSTR fn) {
DWORD len, err, walker, isfound;
LPWSTR drives = NULL;
LPWSTR target = NULL;
LPWSTR ret = NULL;
wchar_t tmplt[3] = L" :"; /* Template */
/*Get list of drive letters */
len = GetLogicalDriveStringsW(0,NULL);
drives = calloc(len,sizeof(wchar_t));
if (!drives) return NULL;
len = GetLogicalDriveStringsW(len,drives);
/*Allocatate memory */
target = calloc(MAX_PATH + 1,sizeof(wchar_t));
if (!target) {
free(drives);
return NULL;
}
walker = 0;
while ((walker < len) && !(drives[walker] == L'\0' && drives[walker + 1] == L'\0')){
/* search through alphabets */
if(iswalpha(drives[walker])) {
*tmplt = drives[walker]; /* Put drive letter */
err = QueryDosDeviceW(tmplt,target,MAX_PATH);
if(!err) {
free(drives);
free(target);
return NULL;
}
if( _wcsnicmp(target,fn,wcslen(target)) == 0) break;
wmemset(target,L'\0',MAX_PATH);
walker++;
} else walker++;
}
if (!iswalpha(*tmplt)) {
free(drives);
free(target);
return NULL; /* Finish walking without finding correct drive */
}
ret = calloc(MAX_PATH + 1,sizeof(wchar_t));
if (!ret) {
free(drives);
free(target);
return NULL;
}
_snwprintf(ret,MAX_PATH,L"%ws%ws",tmplt,fn+wcslen(target));
return ret;
}
/* XP method of retrieving filename from handles, based on:
http://msdn.microsoft.com/en-us/library/aa366789%28VS.85%29.aspx
*/
static LPWSTR xp_getfilepath(const HANDLE f, const LARGE_INTEGER fsize){
HANDLE hFileMap = NULL;
void* pMem = NULL;
LPWSTR temp, ret;
DWORD err;
temp = calloc(MAX_PATH + 1, sizeof(wchar_t));
if (!temp) goto errormap;
/* CreateFileMappingW limitation: Cannot map 0 byte files, so extend it to 1 byte */
if (!fsize.QuadPart) {
SetFilePointer(f, 1, NULL, FILE_BEGIN);
err = SetEndOfFile(f);
if(!temp) goto errormap;
}
hFileMap = CreateFileMappingW(f,NULL,PAGE_READONLY,0,1,NULL);
if(!hFileMap) goto errormap;
pMem = MapViewOfFile(hFileMap, FILE_MAP_READ, 0, 0, 1);
if(!pMem) goto errormap;
err = GetMappedFileNameW(GetCurrentProcess(),pMem,temp,MAX_PATH);
if(!err) goto errormap;
if (pMem) UnmapViewOfFile(pMem);
if (hFileMap) CloseHandle(hFileMap);
ret = xp_normalize_fn(temp);
free(temp);
return ret;
errormap:
if (temp) free(temp);
if (pMem) UnmapViewOfFile(pMem);
if (hFileMap) CloseHandle(hFileMap);
_set_errno(EBADF);
return NULL;
}
#endif /* _CHECK_SPACE_BY_PSAPI_METHOD_ */
static int
checkfreespace (const HANDLE f, const ULONGLONG requiredspace)
{
LPWSTR dirpath, volumeid, volumepath;
ULARGE_INTEGER freespace;
LARGE_INTEGER currentsize;
DWORD check, volumeserial;
BY_HANDLE_FILE_INFORMATION fileinfo;
HANDLE vol;
/* Get current size */
check = GetFileSizeEx (f, &currentsize);
if (!check)
{
_set_errno(EBADF);
return -1; /* Error checking file size */
}
/* Short circuit disk space check if shrink operation */
if ((ULONGLONG)currentsize.QuadPart >= requiredspace)
return 0;
/* We check available space to user before attempting to truncate */
#if (_CHECK_SPACE_BY_VISTA_METHOD_ == 1)
/* Get path length */
DWORD err;
LPWSTR filepath = NULL;
check = GetFinalPathNameByHandleW(f,filepath,0,FILE_NAME_NORMALIZED|VOLUME_NAME_GUID);
err = GetLastError();
if (err == ERROR_PATH_NOT_FOUND || err == ERROR_INVALID_PARAMETER) {
_set_errno(EINVAL);
return -1; /* IO error */
}
filepath = calloc(check + 1,sizeof(wchar_t));
if (!filepath) {
_set_errno(EBADF);
return -1; /* Out of memory */
}
check = GetFinalPathNameByHandleW(f,filepath,check,FILE_NAME_NORMALIZED|VOLUME_NAME_GUID);
/* FIXME: last error was set to error 87 (0x57)
"The parameter is incorrect." for some reason but works out */
if (!check) {
_set_errno(EBADF);
return -1; /* Error resolving filename */
}
#endif /* _CHECK_SPACE_BY_VISTA_METHOD_ */
#if (_CHECK_SPACE_BY_PSAPI_METHOD_ == 1)
LPWSTR filepath = NULL;
filepath = xp_getfilepath(f,currentsize);
/* Get durectory path */
dirpath = getdirpath(filepath);
free(filepath);
filepath = NULL;
if (!dirpath) {
_set_errno(EBADF);
return -1; /* Out of memory */
}
#endif /* _CHECK_SPACE_BY_PSAPI_METHOD_ */
#if _CHECK_SPACE_BY_VOLUME_METHOD_
if(!GetFileInformationByHandle(f,&fileinfo)) {
_set_errno(EINVAL);
return -1; /* Resolution failure */
}
volumeid = calloc(51,sizeof(wchar_t));
volumepath = calloc(MAX_PATH+2,sizeof(wchar_t));
if(!volumeid || !volumepath) {
_set_errno(EBADF);
return -1; /* Out of memory */
}
dirpath = NULL;
vol = FindFirstVolumeW(volumeid,50);
/* wprintf(L"%d - %ws\n",wcslen(volumeid),volumeid); */
do {
check = GetVolumeInformationW(volumeid,volumepath,MAX_PATH+1,&volumeserial,NULL,NULL,NULL,0);
/* wprintf(L"GetVolumeInformationW %d id %ws path %ws error %d\n",check,volumeid,volumepath,GetLastError()); */
if(volumeserial == fileinfo.dwVolumeSerialNumber) {
dirpath = volumeid;
break;
}
} while (FindNextVolumeW(vol,volumeid,50));
FindVolumeClose(vol);
if(!dirpath) free(volumeid); /* we found the volume */
free(volumepath);
#endif /* _CHECK_SPACE_BY_VOLUME_METHOD_ */
/* Get available free space */
check = GetDiskFreeSpaceExW(dirpath,&freespace,NULL,NULL);
//wprintf(L"freespace %I64u\n",freespace);
free(dirpath);
if(!check) {
_set_errno(EFBIG);
return -1; /* Error getting free space */
}
/* Check space requirements */
if ((requiredspace - currentsize.QuadPart) > freespace.QuadPart)
{
_set_errno(EFBIG); /* File too big for disk */
return -1;
} /* We have enough space to truncate/expand */
return 0;
}
int ftruncate64(int __fd, _off64_t __length) {
HANDLE f;
LARGE_INTEGER quad;
DWORD check;
int ret = 0;
__int64 pos;
/* Sanity check */
if (__length < 0) {
goto errorout;
}
/* Get Win32 Handle */
if(__fd == -1) {
goto errorout;
}
f = (HANDLE)_get_osfhandle(__fd);
if (f == INVALID_HANDLE_VALUE || (GetFileType(f) != FILE_TYPE_DISK)) {
_set_errno(EBADF);
return -1;
}
/* Save position */
if((pos = _telli64(__fd)) == -1LL){
goto errorout;
}
/* Check available space */
check = checkfreespace(f,__length);
if (check != 0) {
return -1; /* Error, errno already set */
}
quad.QuadPart = __length;
check = SetFilePointer(f, (LONG)quad.LowPart, &(quad.HighPart), FILE_BEGIN);
if (check == INVALID_SET_FILE_POINTER && quad.LowPart != INVALID_SET_FILE_POINTER) {
switch (GetLastError()) {
case ERROR_NEGATIVE_SEEK:
_set_errno(EFBIG); /* file too big? */
return -1;
case INVALID_SET_FILE_POINTER:
_set_errno(EINVAL); /* shouldn't happen */
return -1;
default:
_set_errno(EINVAL); /* shouldn't happen */
return -1;
}
}
check = SetEndOfFile(f);
if (!check) {
goto errorout;
}
if(_lseeki64(__fd,pos,SEEK_SET) == -1LL){
goto errorout;
}
return ret;
errorout:
_set_errno(EINVAL);
return -1;
}
#if (TEST_FTRUNCATE64 == 1)
int main(){
LARGE_INTEGER sz;
ULARGE_INTEGER freespace;
int f;
LPWSTR path, dir;
sz.QuadPart = 0LL;
f = _open("XXX.tmp", _O_BINARY|_O_CREAT|_O_RDWR, _S_IREAD | _S_IWRITE);
wprintf(L"%d\n",ftruncate64(f,12));
wprintf(L"%d\n",ftruncate64(f,20));
wprintf(L"%d\n",ftruncate64(f,15));
/* path = xp_getfilepath((HANDLE)_get_osfhandle(f),sz);
dir = getdirpath(path);
GetDiskFreeSpaceExW(dir,&freespace,NULL,NULL);
wprintf(L"fs - %ws\n",path);
wprintf(L"dirfs - %ws\n",dir);
wprintf(L"free - %I64u\n",freespace.QuadPart);
free(dir);
free(path);*/
_close(f);
return 0;
}
#endif /* TEST_FTRUNCATE64 */
#if (TEST_FTRUNCATE64 == 2)
int main() {
FILE *f;
int fd;
char buf[100];
int cnt;
unlink("test.out");
f = fopen("test.out","w+");
fd = fileno(f);
write(fd,"abc",3);
fflush(f);
printf ("err: %d\n", ftruncate64(fd,10));
cnt = read(fd,buf,100);
printf("cnt = %d\n",cnt);
return 0;
}
#endif /* TEST_FTRUNCATE64 */
#if (TEST_FTRUNCATE64 == 3)
int main() {
FILE *f;
int fd;
char buf[100];
int cnt;
unlink("test.out");
f = fopen("test.out","w+");
fd = fileno(f);
write(fd,"abc",3);
fflush(f);
ftruncate64(fd,0);
write(fd,"def",3);
fclose(f);
f = fopen("test.out","r");
cnt = fread(buf,1,100,f);
printf("cnt = %d\n",cnt);
return 0;
}
#endif /* TEST_FTRUNCATE64 */