diff options
Diffstat (limited to 'private/crt32/lowio/dup.c')
| -rw-r--r-- | private/crt32/lowio/dup.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/private/crt32/lowio/dup.c b/private/crt32/lowio/dup.c new file mode 100644 index 000000000..1eaa12597 --- /dev/null +++ b/private/crt32/lowio/dup.c @@ -0,0 +1,156 @@ +/*** +*dup.c - OS/2 duplicate file handles +* +* Copyright (c) 1989-1992, Microsoft Corporation. All rights reserved. +* +*Purpose: +* defines _dup() - duplicate file handles +* +*Revision History: +* 06-09-89 PHG Module created, based on asm version +* 03-12-90 GJF Made calling type _CALLTYPE2 (for now), added #include +* <cruntime.h> and fixed the copyright. Also, cleaned up +* the formatting a bit. +* 04-03-90 GJF Now _CALLTYPE1. +* 07-24-90 SBM Removed '32' from API names +* 08-14-90 SBM Compiles cleanly with -W3 +* 09-28-90 GJF New-style function declarator. +* 12-04-90 GJF Appended Win32 version onto the source with #ifdef-s. +* It is enough different that there is little point in +* trying to more closely merge the two versions. +* 12-04-90 SRW Changed to include <oscalls.h> instead of <doscalls.h> +* 12-06-90 SRW Changed to use _osfile and _osfhnd instead of _osfinfo +* 01-16-91 GJF ANSI naming. +* 02-07-91 SRW Changed to call _get_osfhandle [_WIN32_] +* 02-18-91 SRW Changed to call _free_osfhnd [_WIN32_] +* 02-25-91 SRW Renamed _get_free_osfhnd to be _alloc_osfhnd [_WIN32_] +* 02-13-92 GJF Replaced _nfile by _nhandle for Win32. +* 09-03-92 GJF Added explicit check for unopened handles [_WIN32_]. +* +*******************************************************************************/ + +#include <cruntime.h> +#include <oscalls.h> +#include <errno.h> +#include <os2dll.h> +#include <io.h> +#include <msdos.h> +#include <internal.h> +#include <stdlib.h> + +/*** +*int _dup(fh) - duplicate a file handle +* +*Purpose: +* Assigns another file handle to the file associated with the +* handle fh. The next available file handle is assigned. +* +* Multi-thread: Be sure not to hold two file handle locks +* at the same time! +* +*Entry: +* int fh - file handle to duplicate +* +*Exit: +* returns new file handle if successful +* returns -1 (and sets errno) if fails +* +*Exceptions: +* +*******************************************************************************/ + +int _CALLTYPE1 _dup ( + int fh + ) +{ + ULONG dosretval; /* OS/2 return value */ + int newfh; /* variable for new file handle */ + char fileinfo; /* _osfile info for file */ + + /* validate file handle */ +#ifdef _WIN32_ + if ( ((unsigned)fh >= (unsigned)_nhandle) || + !(_osfile[fh] & FOPEN) ) { +#else + if ((unsigned)fh >= (unsigned)_nfile) { +#endif + errno = EBADF; + _doserrno = 0; /* no OS/2 error */ + return -1; + } + + _lock_fh(fh); /* lock file handle */ + fileinfo = _osfile[fh]; /* get file info for file */ + + /* create duplicate handle */ + +#ifdef _CRUISER_ + + newfh = -1; /* ask for new handle */ + dosretval = DOSDUPHANDLE(fh, &newfh); + + /* validate range of new handle */ + if (dosretval == 0 && (unsigned)newfh >= (unsigned)_nfile) { + /* file handle is not in range -- close it and return error */ + _doserrno = DOSCLOSE(newfh); + errno = EMFILE; + _unlock_fh(fh); + return -1; + } + +#else /* ndef _CRUISER_ */ + +#ifdef _WIN32_ + { + long new_osfhandle; + + if ( (newfh = _alloc_osfhnd()) == -1 ) { + errno = EMFILE; /* too many files error */ + _doserrno = 0L; /* not an OS error */ + _unlock_fh(fh); + return -1; /* return error to caller */ + } + + /* + * duplicate the file handle + */ + + if ( !(DuplicateHandle(GetCurrentProcess(), + (HANDLE)_get_osfhandle(fh), + GetCurrentProcess(), + (PHANDLE)&new_osfhandle, + 0L, + TRUE, + DUPLICATE_SAME_ACCESS)) ) + { + dosretval = GetLastError(); + } + else { + _set_osfhnd(newfh, new_osfhandle); + dosretval = 0; + } + } + + _unlock_fh(newfh); + +#else /* ndef _WIN32_ */ + +#error ERROR - ONLY CRUISER OR WIN32 TARGET SUPPORTED! + +#endif /* _WIN32_ */ + +#endif /* _CRUISER_ */ + + _unlock_fh(fh); /* unlock file handle */ + + if (dosretval) { + /* OS/2 error -- map and return */ + _dosmaperr(dosretval); + return -1; + } + + /* copy _osfile info */ + _osfile[newfh] = fileinfo; + + return newfh; +} |