mirror of https://github.com/python/cpython
Rationalizing the fallback code for portable fseek -- this is all much
simpler if we use fgetpos and fsetpos, rather than trying to mess with platform-specific TELL64 alternatives. Of course, this hasn't been tested on a 64-bit platform, so I may have to withdraw this -- but I'm hopeful, and Trent Mick supports this patch!
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@ -55,15 +55,6 @@
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#include <errno.h>
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#endif
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/* define the appropriate 64-bit capable tell() function */
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#if defined(MS_WIN64)
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#define TELL64 _telli64
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#elif defined(__NetBSD__) || defined(__OpenBSD__) || defined(__FreeBSD__) || defined(_HAVE_BSDI) || defined(__APPLE__)
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/* NOTE: this is only used on older
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NetBSD prior to f*o() funcions */
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#define TELL64(fd) lseek((fd),0,SEEK_CUR)
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#endif
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typedef struct {
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PyObject_HEAD
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@ -257,25 +248,20 @@ _portable_fseek(FILE *fp, off_t offset, int whence)
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#elif defined(__BEOS__)
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return _fseek(fp, offset, whence);
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#elif defined(HAVE_LARGEFILE_SUPPORT) && SIZEOF_FPOS_T >= 8
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/* lacking a 64-bit capable fseek() (as Win64 does) use a 64-bit capable
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fsetpos() and tell() to implement fseek()*/
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/* lacking a 64-bit capable fseek(), use a 64-bit capable fsetpos()
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and fgetpos() to implement fseek()*/
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fpos_t pos;
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switch (whence) {
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case SEEK_CUR:
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if (fgetpos(fp, &pos) != 0)
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return -1;
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offset += pos;
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break;
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case SEEK_END:
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/* do a "no-op" seek first to sync the buffering so that
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the low-level tell() can be used correctly */
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if (fseek(fp, 0, SEEK_END) != 0)
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return -1;
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if ((pos = TELL64(fileno(fp))) == -1L)
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return -1;
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offset += pos;
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break;
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/* case SEEK_SET: break; */
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case SEEK_END:
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if (fseek(fp, 0, SEEK_END) != 0)
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return -1;
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/* fall through */
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case SEEK_CUR:
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if (fgetpos(fp, &pos) != 0)
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return -1;
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offset += pos;
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break;
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/* case SEEK_SET: break; */
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}
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return fsetpos(fp, &offset);
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#else
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