cpython/Objects/fileobject.c

1285 lines
27 KiB
C

/* File object implementation */
#include "Python.h"
#include "structmember.h"
#ifndef DONT_HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif /* DONT_HAVE_SYS_TYPES_H */
/* We expect that fstat exists on most systems.
It's confirmed on Unix, Mac and Windows.
If you don't have it, add #define DONT_HAVE_FSTAT to your config.h. */
#ifndef DONT_HAVE_FSTAT
#define HAVE_FSTAT
#ifndef DONT_HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifndef DONT_HAVE_SYS_STAT_H
#include <sys/stat.h>
#else
#ifdef HAVE_STAT_H
#include <stat.h>
#endif
#endif
#endif /* DONT_HAVE_FSTAT */
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef MS_WIN32
#define fileno _fileno
/* can (almost fully) duplicate with _chsize, see file_truncate */
#define HAVE_FTRUNCATE
#endif
#ifdef macintosh
#ifdef USE_GUSI
#define HAVE_FTRUNCATE
#endif
#endif
#ifdef __MWERKS__
/* Mwerks fopen() doesn't always set errno */
#define NO_FOPEN_ERRNO
#endif
#define BUF(v) PyString_AS_STRING((PyStringObject *)v)
#ifndef DONT_HAVE_ERRNO_H
#include <errno.h>
#endif
/* define the appropriate 64-bit capable tell() function */
#if defined(MS_WIN64)
#define TELL64 _telli64
#elif defined(__NetBSD__) || defined(__OpenBSD__)
/* NOTE: this is only used on older
NetBSD prior to f*o() funcions */
#define TELL64(fd) lseek((fd),0,SEEK_CUR)
#endif
typedef struct {
PyObject_HEAD
FILE *f_fp;
PyObject *f_name;
PyObject *f_mode;
int (*f_close)(FILE *);
int f_softspace; /* Flag used by 'print' command */
int f_binary; /* Flag which indicates whether the file is open
open in binary (1) or test (0) mode */
} PyFileObject;
FILE *
PyFile_AsFile(PyObject *f)
{
if (f == NULL || !PyFile_Check(f))
return NULL;
else
return ((PyFileObject *)f)->f_fp;
}
PyObject *
PyFile_Name(PyObject *f)
{
if (f == NULL || !PyFile_Check(f))
return NULL;
else
return ((PyFileObject *)f)->f_name;
}
PyObject *
PyFile_FromFile(FILE *fp, char *name, char *mode, int (*close)(FILE *))
{
PyFileObject *f = PyObject_NEW(PyFileObject, &PyFile_Type);
if (f == NULL)
return NULL;
f->f_fp = NULL;
f->f_name = PyString_FromString(name);
f->f_mode = PyString_FromString(mode);
f->f_close = close;
f->f_softspace = 0;
if (strchr(mode,'b') != NULL)
f->f_binary = 1;
else
f->f_binary = 0;
if (f->f_name == NULL || f->f_mode == NULL) {
Py_DECREF(f);
return NULL;
}
f->f_fp = fp;
return (PyObject *) f;
}
PyObject *
PyFile_FromString(char *name, char *mode)
{
extern int fclose(FILE *);
PyFileObject *f;
f = (PyFileObject *) PyFile_FromFile((FILE *)NULL, name, mode, fclose);
if (f == NULL)
return NULL;
#ifdef HAVE_FOPENRF
if (*mode == '*') {
FILE *fopenRF();
f->f_fp = fopenRF(name, mode+1);
}
else
#endif
{
Py_BEGIN_ALLOW_THREADS
f->f_fp = fopen(name, mode);
Py_END_ALLOW_THREADS
}
if (f->f_fp == NULL) {
#ifdef NO_FOPEN_ERRNO
/* Metroworks only, not testable, so unchanged */
if ( errno == 0 ) {
PyErr_SetString(PyExc_IOError, "Cannot open file");
Py_DECREF(f);
return NULL;
}
#endif
PyErr_SetFromErrnoWithFilename(PyExc_IOError, name);
Py_DECREF(f);
return NULL;
}
return (PyObject *)f;
}
void
PyFile_SetBufSize(PyObject *f, int bufsize)
{
if (bufsize >= 0) {
#ifdef HAVE_SETVBUF
int type;
switch (bufsize) {
case 0:
type = _IONBF;
break;
case 1:
type = _IOLBF;
bufsize = BUFSIZ;
break;
default:
type = _IOFBF;
}
setvbuf(((PyFileObject *)f)->f_fp, (char *)NULL,
type, bufsize);
#else /* !HAVE_SETVBUF */
if (bufsize <= 1)
setbuf(((PyFileObject *)f)->f_fp, (char *)NULL);
#endif /* !HAVE_SETVBUF */
}
}
static PyObject *
err_closed(void)
{
PyErr_SetString(PyExc_ValueError, "I/O operation on closed file");
return NULL;
}
/* Methods */
static void
file_dealloc(PyFileObject *f)
{
if (f->f_fp != NULL && f->f_close != NULL) {
Py_BEGIN_ALLOW_THREADS
(*f->f_close)(f->f_fp);
Py_END_ALLOW_THREADS
}
if (f->f_name != NULL) {
Py_DECREF(f->f_name);
}
if (f->f_mode != NULL) {
Py_DECREF(f->f_mode);
}
PyObject_DEL(f);
}
static PyObject *
file_repr(PyFileObject *f)
{
char buf[300];
sprintf(buf, "<%s file '%.256s', mode '%.10s' at %p>",
f->f_fp == NULL ? "closed" : "open",
PyString_AsString(f->f_name),
PyString_AsString(f->f_mode),
f);
return PyString_FromString(buf);
}
static PyObject *
file_close(PyFileObject *f, PyObject *args)
{
int sts = 0;
if (!PyArg_NoArgs(args))
return NULL;
if (f->f_fp != NULL) {
if (f->f_close != NULL) {
Py_BEGIN_ALLOW_THREADS
errno = 0;
sts = (*f->f_close)(f->f_fp);
Py_END_ALLOW_THREADS
}
f->f_fp = NULL;
}
if (sts == EOF)
return PyErr_SetFromErrno(PyExc_IOError);
if (sts != 0)
return PyInt_FromLong((long)sts);
Py_INCREF(Py_None);
return Py_None;
}
/* a portable fseek() function
return 0 on success, non-zero on failure (with errno set) */
int
#if defined(HAVE_LARGEFILE_SUPPORT) && SIZEOF_OFF_T < 8 && SIZEOF_FPOS_T >= 8
_portable_fseek(FILE *fp, fpos_t offset, int whence)
#else
_portable_fseek(FILE *fp, off_t offset, int whence)
#endif
{
#if defined(HAVE_FSEEKO)
return fseeko(fp, offset, whence);
#elif defined(HAVE_FSEEK64)
return fseek64(fp, offset, whence);
#elif defined(__BEOS__)
return _fseek(fp, offset, whence);
#elif defined(HAVE_LARGEFILE_SUPPORT) && SIZEOF_FPOS_T >= 8
/* lacking a 64-bit capable fseek() (as Win64 does) use a 64-bit capable
fsetpos() and tell() to implement fseek()*/
fpos_t pos;
switch (whence) {
case SEEK_CUR:
if (fgetpos(fp, &pos) != 0)
return -1;
offset += pos;
break;
case SEEK_END:
/* do a "no-op" seek first to sync the buffering so that
the low-level tell() can be used correctly */
if (fseek(fp, 0, SEEK_END) != 0)
return -1;
if ((pos = TELL64(fileno(fp))) == -1L)
return -1;
offset += pos;
break;
/* case SEEK_SET: break; */
}
return fsetpos(fp, &offset);
#else
return fseek(fp, offset, whence);
#endif
}
/* a portable ftell() function
Return -1 on failure with errno set appropriately, current file
position on success */
#if defined(HAVE_LARGEFILE_SUPPORT) && SIZEOF_OFF_T < 8 && SIZEOF_FPOS_T >= 8
fpos_t
#else
off_t
#endif
_portable_ftell(FILE* fp)
{
#if defined(HAVE_FTELLO) && defined(HAVE_LARGEFILE_SUPPORT)
return ftello(fp);
#elif defined(HAVE_FTELL64) && defined(HAVE_LARGEFILE_SUPPORT)
return ftell64(fp);
#elif SIZEOF_FPOS_T >= 8 && defined(HAVE_LARGEFILE_SUPPORT)
fpos_t pos;
if (fgetpos(fp, &pos) != 0)
return -1;
return pos;
#else
return ftell(fp);
#endif
}
static PyObject *
file_seek(PyFileObject *f, PyObject *args)
{
int whence;
int ret;
#if defined(HAVE_LARGEFILE_SUPPORT) && SIZEOF_OFF_T < 8 && SIZEOF_FPOS_T >= 8
fpos_t offset, pos;
#else
off_t offset;
#endif /* !MS_WIN64 */
PyObject *offobj;
if (f->f_fp == NULL)
return err_closed();
whence = 0;
if (!PyArg_ParseTuple(args, "O|i:seek", &offobj, &whence))
return NULL;
#if !defined(HAVE_LARGEFILE_SUPPORT)
offset = PyInt_AsLong(offobj);
#else
offset = PyLong_Check(offobj) ?
PyLong_AsLongLong(offobj) : PyInt_AsLong(offobj);
#endif
if (PyErr_Occurred())
return NULL;
Py_BEGIN_ALLOW_THREADS
errno = 0;
ret = _portable_fseek(f->f_fp, offset, whence);
Py_END_ALLOW_THREADS
if (ret != 0) {
PyErr_SetFromErrno(PyExc_IOError);
clearerr(f->f_fp);
return NULL;
}
Py_INCREF(Py_None);
return Py_None;
}
#ifdef HAVE_FTRUNCATE
static PyObject *
file_truncate(PyFileObject *f, PyObject *args)
{
int ret;
#if defined(HAVE_LARGEFILE_SUPPORT) && SIZEOF_OFF_T < 8 && SIZEOF_FPOS_T >= 8
fpos_t newsize;
#else
off_t newsize;
#endif
PyObject *newsizeobj;
if (f->f_fp == NULL)
return err_closed();
newsizeobj = NULL;
if (!PyArg_ParseTuple(args, "|O:truncate", &newsizeobj))
return NULL;
if (newsizeobj != NULL) {
#if !defined(HAVE_LARGEFILE_SUPPORT)
newsize = PyInt_AsLong(newsizeobj);
#else
newsize = PyLong_Check(newsizeobj) ?
PyLong_AsLongLong(newsizeobj) :
PyInt_AsLong(newsizeobj);
#endif
if (PyErr_Occurred())
return NULL;
} else {
/* Default to current position*/
Py_BEGIN_ALLOW_THREADS
errno = 0;
newsize = _portable_ftell(f->f_fp);
Py_END_ALLOW_THREADS
if (newsize == -1) {
PyErr_SetFromErrno(PyExc_IOError);
clearerr(f->f_fp);
return NULL;
}
}
Py_BEGIN_ALLOW_THREADS
errno = 0;
ret = fflush(f->f_fp);
Py_END_ALLOW_THREADS
if (ret != 0) goto onioerror;
#ifdef MS_WIN32
/* can use _chsize; if, however, the newsize overflows 32-bits then
_chsize is *not* adequate; in this case, an OverflowError is raised */
if (newsize > LONG_MAX) {
PyErr_SetString(PyExc_OverflowError,
"the new size is too long for _chsize (it is limited to 32-bit values)");
return NULL;
} else {
Py_BEGIN_ALLOW_THREADS
errno = 0;
ret = _chsize(fileno(f->f_fp), newsize);
Py_END_ALLOW_THREADS
if (ret != 0) goto onioerror;
}
#else
Py_BEGIN_ALLOW_THREADS
errno = 0;
ret = ftruncate(fileno(f->f_fp), newsize);
Py_END_ALLOW_THREADS
if (ret != 0) goto onioerror;
#endif /* !MS_WIN32 */
Py_INCREF(Py_None);
return Py_None;
onioerror:
PyErr_SetFromErrno(PyExc_IOError);
clearerr(f->f_fp);
return NULL;
}
#endif /* HAVE_FTRUNCATE */
static PyObject *
file_tell(PyFileObject *f, PyObject *args)
{
#if defined(HAVE_LARGEFILE_SUPPORT) && SIZEOF_OFF_T < 8 && SIZEOF_FPOS_T >= 8
fpos_t pos;
#else
off_t pos;
#endif
if (f->f_fp == NULL)
return err_closed();
if (!PyArg_NoArgs(args))
return NULL;
Py_BEGIN_ALLOW_THREADS
errno = 0;
pos = _portable_ftell(f->f_fp);
Py_END_ALLOW_THREADS
if (pos == -1) {
PyErr_SetFromErrno(PyExc_IOError);
clearerr(f->f_fp);
return NULL;
}
#if !defined(HAVE_LARGEFILE_SUPPORT)
return PyInt_FromLong(pos);
#else
return PyLong_FromLongLong(pos);
#endif
}
static PyObject *
file_fileno(PyFileObject *f, PyObject *args)
{
if (f->f_fp == NULL)
return err_closed();
if (!PyArg_NoArgs(args))
return NULL;
return PyInt_FromLong((long) fileno(f->f_fp));
}
static PyObject *
file_flush(PyFileObject *f, PyObject *args)
{
int res;
if (f->f_fp == NULL)
return err_closed();
if (!PyArg_NoArgs(args))
return NULL;
Py_BEGIN_ALLOW_THREADS
errno = 0;
res = fflush(f->f_fp);
Py_END_ALLOW_THREADS
if (res != 0) {
PyErr_SetFromErrno(PyExc_IOError);
clearerr(f->f_fp);
return NULL;
}
Py_INCREF(Py_None);
return Py_None;
}
static PyObject *
file_isatty(PyFileObject *f, PyObject *args)
{
long res;
if (f->f_fp == NULL)
return err_closed();
if (!PyArg_NoArgs(args))
return NULL;
Py_BEGIN_ALLOW_THREADS
res = isatty((int)fileno(f->f_fp));
Py_END_ALLOW_THREADS
return PyInt_FromLong(res);
}
#if BUFSIZ < 8192
#define SMALLCHUNK 8192
#else
#define SMALLCHUNK BUFSIZ
#endif
#if SIZEOF_INT < 4
#define BIGCHUNK (512 * 32)
#else
#define BIGCHUNK (512 * 1024)
#endif
static size_t
new_buffersize(PyFileObject *f, size_t currentsize)
{
#ifdef HAVE_FSTAT
long pos, end;
struct stat st;
if (fstat(fileno(f->f_fp), &st) == 0) {
end = st.st_size;
/* The following is not a bug: we really need to call lseek()
*and* ftell(). The reason is that some stdio libraries
mistakenly flush their buffer when ftell() is called and
the lseek() call it makes fails, thereby throwing away
data that cannot be recovered in any way. To avoid this,
we first test lseek(), and only call ftell() if lseek()
works. We can't use the lseek() value either, because we
need to take the amount of buffered data into account.
(Yet another reason why stdio stinks. :-) */
pos = lseek(fileno(f->f_fp), 0L, SEEK_CUR);
if (pos >= 0)
pos = ftell(f->f_fp);
if (pos < 0)
clearerr(f->f_fp);
if (end > pos && pos >= 0)
return currentsize + end - pos + 1;
/* Add 1 so if the file were to grow we'd notice. */
}
#endif
if (currentsize > SMALLCHUNK) {
/* Keep doubling until we reach BIGCHUNK;
then keep adding BIGCHUNK. */
if (currentsize <= BIGCHUNK)
return currentsize + currentsize;
else
return currentsize + BIGCHUNK;
}
return currentsize + SMALLCHUNK;
}
static PyObject *
file_read(PyFileObject *f, PyObject *args)
{
long bytesrequested = -1;
size_t bytesread, buffersize, chunksize;
PyObject *v;
if (f->f_fp == NULL)
return err_closed();
if (!PyArg_ParseTuple(args, "|l:read", &bytesrequested))
return NULL;
if (bytesrequested < 0)
buffersize = new_buffersize(f, (size_t)0);
else
buffersize = bytesrequested;
if (buffersize > INT_MAX) {
PyErr_SetString(PyExc_OverflowError,
"requested number of bytes is more than a Python string can hold");
return NULL;
}
v = PyString_FromStringAndSize((char *)NULL, buffersize);
if (v == NULL)
return NULL;
bytesread = 0;
for (;;) {
Py_BEGIN_ALLOW_THREADS
errno = 0;
chunksize = fread(BUF(v) + bytesread, 1,
buffersize - bytesread, f->f_fp);
Py_END_ALLOW_THREADS
if (chunksize == 0) {
if (!ferror(f->f_fp))
break;
PyErr_SetFromErrno(PyExc_IOError);
clearerr(f->f_fp);
Py_DECREF(v);
return NULL;
}
bytesread += chunksize;
if (bytesread < buffersize)
break;
if (bytesrequested < 0) {
buffersize = new_buffersize(f, buffersize);
if (_PyString_Resize(&v, buffersize) < 0)
return NULL;
}
}
if (bytesread != buffersize)
_PyString_Resize(&v, bytesread);
return v;
}
static PyObject *
file_readinto(PyFileObject *f, PyObject *args)
{
char *ptr;
size_t ntodo, ndone, nnow;
if (f->f_fp == NULL)
return err_closed();
if (!PyArg_Parse(args, "w#", &ptr, &ntodo))
return NULL;
ndone = 0;
while (ntodo > 0) {
Py_BEGIN_ALLOW_THREADS
errno = 0;
nnow = fread(ptr+ndone, 1, ntodo, f->f_fp);
Py_END_ALLOW_THREADS
if (nnow == 0) {
if (!ferror(f->f_fp))
break;
PyErr_SetFromErrno(PyExc_IOError);
clearerr(f->f_fp);
return NULL;
}
ndone += nnow;
ntodo -= nnow;
}
return PyInt_FromLong((long)ndone);
}
/* Internal routine to get a line.
Size argument interpretation:
> 0: max length;
= 0: read arbitrary line;
< 0: strip trailing '\n', raise EOFError if EOF reached immediately
*/
static PyObject *
get_line(PyFileObject *f, int n)
{
register FILE *fp;
register int c;
register char *buf, *end;
size_t n1, n2;
PyObject *v;
fp = f->f_fp;
n2 = n > 0 ? n : 100;
v = PyString_FromStringAndSize((char *)NULL, n2);
if (v == NULL)
return NULL;
buf = BUF(v);
end = buf + n2;
Py_BEGIN_ALLOW_THREADS
for (;;) {
if ((c = getc(fp)) == EOF) {
clearerr(fp);
Py_BLOCK_THREADS
if (PyErr_CheckSignals()) {
Py_DECREF(v);
return NULL;
}
if (n < 0 && buf == BUF(v)) {
Py_DECREF(v);
PyErr_SetString(PyExc_EOFError,
"EOF when reading a line");
return NULL;
}
Py_UNBLOCK_THREADS
break;
}
if ((*buf++ = c) == '\n') {
if (n < 0)
buf--;
break;
}
if (buf == end) {
if (n > 0)
break;
n1 = n2;
n2 += 1000;
if (n2 > INT_MAX) {
PyErr_SetString(PyExc_OverflowError,
"line is longer than a Python string can hold");
return NULL;
}
Py_BLOCK_THREADS
if (_PyString_Resize(&v, n2) < 0)
return NULL;
Py_UNBLOCK_THREADS
buf = BUF(v) + n1;
end = BUF(v) + n2;
}
}
Py_END_ALLOW_THREADS
n1 = buf - BUF(v);
if (n1 != n2)
_PyString_Resize(&v, n1);
return v;
}
/* External C interface */
PyObject *
PyFile_GetLine(PyObject *f, int n)
{
if (f == NULL) {
PyErr_BadInternalCall();
return NULL;
}
if (!PyFile_Check(f)) {
PyObject *reader;
PyObject *args;
PyObject *result;
reader = PyObject_GetAttrString(f, "readline");
if (reader == NULL)
return NULL;
if (n <= 0)
args = Py_BuildValue("()");
else
args = Py_BuildValue("(i)", n);
if (args == NULL) {
Py_DECREF(reader);
return NULL;
}
result = PyEval_CallObject(reader, args);
Py_DECREF(reader);
Py_DECREF(args);
if (result != NULL && !PyString_Check(result)) {
Py_DECREF(result);
result = NULL;
PyErr_SetString(PyExc_TypeError,
"object.readline() returned non-string");
}
if (n < 0 && result != NULL) {
char *s = PyString_AsString(result);
int len = PyString_Size(result);
if (len == 0) {
Py_DECREF(result);
result = NULL;
PyErr_SetString(PyExc_EOFError,
"EOF when reading a line");
}
else if (s[len-1] == '\n') {
if (result->ob_refcnt == 1)
_PyString_Resize(&result, len-1);
else {
PyObject *v;
v = PyString_FromStringAndSize(s,
len-1);
Py_DECREF(result);
result = v;
}
}
}
return result;
}
if (((PyFileObject*)f)->f_fp == NULL)
return err_closed();
return get_line((PyFileObject *)f, n);
}
/* Python method */
static PyObject *
file_readline(PyFileObject *f, PyObject *args)
{
int n = -1;
if (f->f_fp == NULL)
return err_closed();
if (!PyArg_ParseTuple(args, "|i:readline", &n))
return NULL;
if (n == 0)
return PyString_FromString("");
if (n < 0)
n = 0;
return get_line(f, n);
}
static PyObject *
file_readlines(PyFileObject *f, PyObject *args)
{
long sizehint = 0;
PyObject *list;
PyObject *line;
char small_buffer[SMALLCHUNK];
char *buffer = small_buffer;
size_t buffersize = SMALLCHUNK;
PyObject *big_buffer = NULL;
size_t nfilled = 0;
size_t nread;
size_t totalread = 0;
char *p, *q, *end;
int err;
if (f->f_fp == NULL)
return err_closed();
if (!PyArg_ParseTuple(args, "|l:readlines", &sizehint))
return NULL;
if ((list = PyList_New(0)) == NULL)
return NULL;
for (;;) {
Py_BEGIN_ALLOW_THREADS
errno = 0;
nread = fread(buffer+nfilled, 1, buffersize-nfilled, f->f_fp);
Py_END_ALLOW_THREADS
if (nread == 0) {
sizehint = 0;
if (!ferror(f->f_fp))
break;
PyErr_SetFromErrno(PyExc_IOError);
clearerr(f->f_fp);
error:
Py_DECREF(list);
list = NULL;
goto cleanup;
}
totalread += nread;
p = memchr(buffer+nfilled, '\n', nread);
if (p == NULL) {
/* Need a larger buffer to fit this line */
nfilled += nread;
buffersize *= 2;
if (buffersize > INT_MAX) {
PyErr_SetString(PyExc_OverflowError,
"line is longer than a Python string can hold");
goto error;
}
if (big_buffer == NULL) {
/* Create the big buffer */
big_buffer = PyString_FromStringAndSize(
NULL, buffersize);
if (big_buffer == NULL)
goto error;
buffer = PyString_AS_STRING(big_buffer);
memcpy(buffer, small_buffer, nfilled);
}
else {
/* Grow the big buffer */
_PyString_Resize(&big_buffer, buffersize);
buffer = PyString_AS_STRING(big_buffer);
}
continue;
}
end = buffer+nfilled+nread;
q = buffer;
do {
/* Process complete lines */
p++;
line = PyString_FromStringAndSize(q, p-q);
if (line == NULL)
goto error;
err = PyList_Append(list, line);
Py_DECREF(line);
if (err != 0)
goto error;
q = p;
p = memchr(q, '\n', end-q);
} while (p != NULL);
/* Move the remaining incomplete line to the start */
nfilled = end-q;
memmove(buffer, q, nfilled);
if (sizehint > 0)
if (totalread >= (size_t)sizehint)
break;
}
if (nfilled != 0) {
/* Partial last line */
line = PyString_FromStringAndSize(buffer, nfilled);
if (line == NULL)
goto error;
if (sizehint > 0) {
/* Need to complete the last line */
PyObject *rest = get_line(f, 0);
if (rest == NULL) {
Py_DECREF(line);
goto error;
}
PyString_Concat(&line, rest);
Py_DECREF(rest);
if (line == NULL)
goto error;
}
err = PyList_Append(list, line);
Py_DECREF(line);
if (err != 0)
goto error;
}
cleanup:
if (big_buffer) {
Py_DECREF(big_buffer);
}
return list;
}
static PyObject *
file_write(PyFileObject *f, PyObject *args)
{
char *s;
int n, n2;
if (f->f_fp == NULL)
return err_closed();
if (!PyArg_Parse(args, f->f_binary ? "s#" : "t#", &s, &n))
return NULL;
f->f_softspace = 0;
Py_BEGIN_ALLOW_THREADS
errno = 0;
n2 = fwrite(s, 1, n, f->f_fp);
Py_END_ALLOW_THREADS
if (n2 != n) {
PyErr_SetFromErrno(PyExc_IOError);
clearerr(f->f_fp);
return NULL;
}
Py_INCREF(Py_None);
return Py_None;
}
static PyObject *
file_writelines(PyFileObject *f, PyObject *args)
{
#define CHUNKSIZE 1000
PyObject *list, *line;
PyObject *result;
int i, j, index, len, nwritten, islist;
if (f->f_fp == NULL)
return err_closed();
if (args == NULL || !PySequence_Check(args)) {
PyErr_SetString(PyExc_TypeError,
"writelines() argument must be a sequence of strings");
return NULL;
}
islist = PyList_Check(args);
/* Strategy: slurp CHUNKSIZE lines into a private list,
checking that they are all strings, then write that list
without holding the interpreter lock, then come back for more. */
index = 0;
if (islist)
list = NULL;
else {
list = PyList_New(CHUNKSIZE);
if (list == NULL)
return NULL;
}
result = NULL;
for (;;) {
if (islist) {
Py_XDECREF(list);
list = PyList_GetSlice(args, index, index+CHUNKSIZE);
if (list == NULL)
return NULL;
j = PyList_GET_SIZE(list);
}
else {
for (j = 0; j < CHUNKSIZE; j++) {
line = PySequence_GetItem(args, index+j);
if (line == NULL) {
if (PyErr_ExceptionMatches(
PyExc_IndexError)) {
PyErr_Clear();
break;
}
/* Some other error occurred.
XXX We may lose some output. */
goto error;
}
PyList_SetItem(list, j, line);
}
}
if (j == 0)
break;
/* Check that all entries are indeed strings. If not,
apply the same rules as for file.write() and
convert the results to strings. This is slow, but
seems to be the only way since all conversion APIs
could potentially execute Python code. */
for (i = 0; i < j; i++) {
PyObject *v = PyList_GET_ITEM(list, i);
if (!PyString_Check(v)) {
const char *buffer;
int len;
if (((f->f_binary &&
PyObject_AsReadBuffer(v,
(const void**)&buffer,
&len)) ||
PyObject_AsCharBuffer(v,
&buffer,
&len))) {
PyErr_SetString(PyExc_TypeError,
"writelines() argument must be a sequence of strings");
goto error;
}
line = PyString_FromStringAndSize(buffer,
len);
if (line == NULL)
goto error;
Py_DECREF(v);
PyList_SET_ITEM(list, i, line);
}
}
/* Since we are releasing the global lock, the
following code may *not* execute Python code. */
Py_BEGIN_ALLOW_THREADS
f->f_softspace = 0;
errno = 0;
for (i = 0; i < j; i++) {
line = PyList_GET_ITEM(list, i);
len = PyString_GET_SIZE(line);
nwritten = fwrite(PyString_AS_STRING(line),
1, len, f->f_fp);
if (nwritten != len) {
Py_BLOCK_THREADS
PyErr_SetFromErrno(PyExc_IOError);
clearerr(f->f_fp);
goto error;
}
}
Py_END_ALLOW_THREADS
if (j < CHUNKSIZE)
break;
index += CHUNKSIZE;
}
Py_INCREF(Py_None);
result = Py_None;
error:
Py_XDECREF(list);
return result;
}
static PyMethodDef file_methods[] = {
{"readline", (PyCFunction)file_readline, 1},
{"read", (PyCFunction)file_read, 1},
{"write", (PyCFunction)file_write, 0},
{"fileno", (PyCFunction)file_fileno, 0},
{"seek", (PyCFunction)file_seek, 1},
#ifdef HAVE_FTRUNCATE
{"truncate", (PyCFunction)file_truncate, 1},
#endif
{"tell", (PyCFunction)file_tell, 0},
{"readinto", (PyCFunction)file_readinto, 0},
{"readlines", (PyCFunction)file_readlines, 1},
{"writelines", (PyCFunction)file_writelines, 0},
{"flush", (PyCFunction)file_flush, 0},
{"close", (PyCFunction)file_close, 0},
{"isatty", (PyCFunction)file_isatty, 0},
{NULL, NULL} /* sentinel */
};
#define OFF(x) offsetof(PyFileObject, x)
static struct memberlist file_memberlist[] = {
{"softspace", T_INT, OFF(f_softspace)},
{"mode", T_OBJECT, OFF(f_mode), RO},
{"name", T_OBJECT, OFF(f_name), RO},
/* getattr(f, "closed") is implemented without this table */
{"closed", T_INT, 0, RO},
{NULL} /* Sentinel */
};
static PyObject *
file_getattr(PyFileObject *f, char *name)
{
PyObject *res;
res = Py_FindMethod(file_methods, (PyObject *)f, name);
if (res != NULL)
return res;
PyErr_Clear();
if (strcmp(name, "closed") == 0)
return PyInt_FromLong((long)(f->f_fp == 0));
return PyMember_Get((char *)f, file_memberlist, name);
}
static int
file_setattr(PyFileObject *f, char *name, PyObject *v)
{
if (v == NULL) {
PyErr_SetString(PyExc_AttributeError,
"can't delete file attributes");
return -1;
}
return PyMember_Set((char *)f, file_memberlist, name, v);
}
PyTypeObject PyFile_Type = {
PyObject_HEAD_INIT(&PyType_Type)
0,
"file",
sizeof(PyFileObject),
0,
(destructor)file_dealloc, /*tp_dealloc*/
0, /*tp_print*/
(getattrfunc)file_getattr, /*tp_getattr*/
(setattrfunc)file_setattr, /*tp_setattr*/
0, /*tp_compare*/
(reprfunc)file_repr, /*tp_repr*/
};
/* Interface for the 'soft space' between print items. */
int
PyFile_SoftSpace(PyObject *f, int newflag)
{
int oldflag = 0;
if (f == NULL) {
/* Do nothing */
}
else if (PyFile_Check(f)) {
oldflag = ((PyFileObject *)f)->f_softspace;
((PyFileObject *)f)->f_softspace = newflag;
}
else {
PyObject *v;
v = PyObject_GetAttrString(f, "softspace");
if (v == NULL)
PyErr_Clear();
else {
if (PyInt_Check(v))
oldflag = PyInt_AsLong(v);
Py_DECREF(v);
}
v = PyInt_FromLong((long)newflag);
if (v == NULL)
PyErr_Clear();
else {
if (PyObject_SetAttrString(f, "softspace", v) != 0)
PyErr_Clear();
Py_DECREF(v);
}
}
return oldflag;
}
/* Interfaces to write objects/strings to file-like objects */
int
PyFile_WriteObject(PyObject *v, PyObject *f, int flags)
{
PyObject *writer, *value, *args, *result;
if (f == NULL) {
PyErr_SetString(PyExc_TypeError, "writeobject with NULL file");
return -1;
}
else if (PyFile_Check(f)) {
FILE *fp = PyFile_AsFile(f);
if (fp == NULL) {
err_closed();
return -1;
}
return PyObject_Print(v, fp, flags);
}
writer = PyObject_GetAttrString(f, "write");
if (writer == NULL)
return -1;
if (flags & Py_PRINT_RAW)
value = PyObject_Str(v);
else
value = PyObject_Repr(v);
if (value == NULL) {
Py_DECREF(writer);
return -1;
}
args = Py_BuildValue("(O)", value);
if (args == NULL) {
Py_DECREF(value);
Py_DECREF(writer);
return -1;
}
result = PyEval_CallObject(writer, args);
Py_DECREF(args);
Py_DECREF(value);
Py_DECREF(writer);
if (result == NULL)
return -1;
Py_DECREF(result);
return 0;
}
int
PyFile_WriteString(char *s, PyObject *f)
{
if (f == NULL) {
/* Should be caused by a pre-existing error */
if (!PyErr_Occurred())
PyErr_SetString(PyExc_SystemError,
"null file for PyFile_WriteString");
return -1;
}
else if (PyFile_Check(f)) {
FILE *fp = PyFile_AsFile(f);
if (fp == NULL) {
err_closed();
return -1;
}
fputs(s, fp);
return 0;
}
else if (!PyErr_Occurred()) {
PyObject *v = PyString_FromString(s);
int err;
if (v == NULL)
return -1;
err = PyFile_WriteObject(v, f, Py_PRINT_RAW);
Py_DECREF(v);
return err;
}
else
return -1;
}
/* Try to get a file-descriptor from a Python object. If the object
is an integer or long integer, its value is returned. If not, the
object's fileno() method is called if it exists; the method must return
an integer or long integer, which is returned as the file descriptor value.
-1 is returned on failure.
*/
int PyObject_AsFileDescriptor(PyObject *o)
{
int fd;
PyObject *meth;
if (PyInt_Check(o)) {
fd = PyInt_AsLong(o);
}
else if (PyLong_Check(o)) {
fd = PyLong_AsLong(o);
}
else if ((meth = PyObject_GetAttrString(o, "fileno")) != NULL)
{
PyObject *fno = PyEval_CallObject(meth, NULL);
Py_DECREF(meth);
if (fno == NULL)
return -1;
if (PyInt_Check(fno)) {
fd = PyInt_AsLong(fno);
Py_DECREF(fno);
}
else if (PyLong_Check(fno)) {
fd = PyLong_AsLong(fno);
Py_DECREF(fno);
}
else {
PyErr_SetString(PyExc_TypeError,
"fileno() returned a non-integer");
Py_DECREF(fno);
return -1;
}
}
else {
PyErr_SetString(PyExc_TypeError,
"argument must be an int, or have a fileno() method.");
return -1;
}
if (fd < 0) {
PyErr_Format(PyExc_ValueError,
"file descriptor cannot be a negative integer (%i)",
fd);
return -1;
}
return fd;
}