#include <sfio/sfhdr.h>
-/* Create a temporary stream for read/write.
-** The stream is originally created as a memory-resident stream.
-** When this memory is exceeded, a real temp file will be created.
-** The temp file creation sequence is somewhat convoluted so that
-** pool/stack/discipline will work correctly.
-**
-** Written by David Korn and Kiem-Phong Vo.
-*/
-
-#if _tmp_rmfail
-
-/* File not removable while there is an open file descriptor.
-** To ensure that temp files are properly removed, we need:
-** 1. A discipline to remove a file when the corresponding stream is closed.
-** Care must be taken to close the file descriptor before removing the
-** file because systems such as NT do not allow file removal while
-** there is an open file handle.
-** 2. An atexit() function is set up to close temp files when process exits.
-** 3. On systems with O_TEMPORARY (e.g., NT), this is used to further ensure
-** that temp files will be removed after the last handle is closed.
-*/
-
-typedef struct _file_s File_t;
-struct _file_s {
- File_t *next; /* link list */
- Sfio_t *f; /* associated stream */
- char name[1]; /* temp file name */
-};
-
-static File_t *File; /* list pf temp files */
-
-static int _tmprmfile(Sfio_t * f, int type, void * val, Sfdisc_t * disc)
-{
- File_t *ff, *last;
-
- NOTUSED(val);
-
- if (type == SF_DPOP) /* don't allow this to pop */
- return -1;
-
- if (type == SF_CLOSING) {
- vtmtxlock(_Sfmutex);
- for (last = NIL(File_t *), ff = File; ff; last = ff, ff = ff->next)
- if (ff->f == f)
- break;
- if (ff) {
- if (!last)
- File = ff->next;
- else
- last->next = ff->next;
-
- if (_Sfnotify)
- (*_Sfnotify) (f, SF_CLOSING, f->file);
- CLOSE(f->file);
- f->file = -1;
- while (remove(ff->name) < 0 && errno == EINTR)
- errno = 0;
-
- free((void *) ff);
- }
- vtmtxunlock(_Sfmutex);
- }
-
- return 0;
-}
-
-static void _rmfiles(void)
-{
- File_t *ff, *next;
-
- vtmtxlock(_Sfmutex);
- for (ff = File; ff; ff = next) {
- next = ff->next;
- _tmprmfile(ff->f, SF_CLOSING, NIL(void *), ff->f->disc);
- }
- vtmtxunlock(_Sfmutex);
-}
-
-static Sfdisc_t Rmdisc =
- { NIL(Sfread_f), NIL(Sfwrite_f), NIL(Sfseek_f), _tmprmfile,
-NIL(Sfdisc_t *) };
-
-#endif /*_tmp_rmfail*/
-
-static int _rmtmp(Sfio_t * f, char *file)
-{
-#if _tmp_rmfail /* remove only when stream is closed */
- File_t *ff;
-
- if (!File)
- atexit(_rmfiles);
-
- if (!(ff = (File_t *) malloc(sizeof(File_t) + strlen(file))))
- return -1;
- vtmtxlock(_Sfmutex);
- ff->f = f;
- strcpy(ff->name, file);
- ff->next = File;
- File = ff;
- vtmtxunlock(_Sfmutex);
-
-#else /* can remove now */
- while (remove(file) < 0 && errno == EINTR)
- errno = 0;
-#endif
-
- return 0;
-}
-
-#include <time.h>
-#define TMPDFLT "/tmp"
-static char **Tmppath, **Tmpcur;
-
char **_sfgetpath(char *path)
{
char *p, **dirs;
return dirs;
}
-
-static int _tmpfd(Sfio_t * f)
-{
- char *file;
- int fd;
- int t;
-
- /* set up path of dirs to create temp files */
- if (!Tmppath && !(Tmppath = _sfgetpath("TMPPATH"))) {
- if (!(Tmppath = (char **) malloc(2 * sizeof(char *))))
- return -1;
- if (!(file = getenv("TMPDIR")))
- file = TMPDFLT;
- if (!(Tmppath[0] = (char *) malloc(strlen(file) + 1))) {
- free(Tmppath);
- Tmppath = NIL(char **);
- return -1;
- }
- strcpy(Tmppath[0], file);
- Tmppath[1] = NIL(char *);
- }
-
- /* set current directory to create this temp file */
- if (Tmpcur)
- Tmpcur += 1;
- if (!Tmpcur || !Tmpcur[0])
- Tmpcur = Tmppath;
-
- file = NIL(char *);
- fd = -1;
- for (t = 0; t < 10; ++t) { /* compute a random name */
- static ulong Key, A;
- if (A == 0 || t > 0) { /* get a quasi-random coefficient */
- int r;
- A = (ulong) time(NIL(time_t *)) ^ (((ulong) (&t)) >> 3);
- if (Key == 0)
- Key = (A >> 16) | ((A & 0xffff) << 16);
- A ^= Key;
- if ((r = (A - 1) & 03) != 0) /* Knuth vol.2, page.16, Thm.A */
- A += 4 - r;
- }
-
- Key = A * Key + 987654321;
- file = sfprints("%s/sf%3.3.32lu.%3.3.32lu",
- Tmpcur[0], (Key >> 15) & 0x7fff, Key & 0x7fff);
-
- if (!file)
- return -1;
-#if _has_oflags
- if ((fd =
- open(file, O_RDWR | O_CREAT | O_EXCL | O_TEMPORARY,
- SF_CREATMODE)) >= 0)
- break;
-#else
- if ((fd = open(file, O_RDONLY)) >= 0) { /* file already exists */
- CLOSE(fd);
- fd = -1;
- } else if ((fd = creat(file, SF_CREATMODE)) >= 0) { /* reopen for read and write */
- CLOSE(fd);
- if ((fd = open(file, O_RDWR)) >= 0)
- break;
-
- /* don't know what happened but must remove file */
- while (remove(file) < 0 && errno == EINTR)
- errno = 0;
- }
-#endif
- }
-
- if (fd >= 0)
- _rmtmp(f, file);
-
- return fd;
-}
-
-static int _tmpexcept(Sfio_t * f, int type, void * val, Sfdisc_t * disc)
-{
- int fd, m;
- Sfio_t *sf;
- Sfio_t newf, savf;
- void (*notifyf) (Sfio_t *, int, int);
-
- NOTUSED(val);
-
- /* the discipline needs to change only under the following exceptions */
- if (type != SF_WRITE && type != SF_SEEK &&
- type != SF_DPUSH && type != SF_DPOP && type != SF_DBUFFER)
- return 0;
-
- /* notify function */
- notifyf = _Sfnotify;
-
- /* try to create the temp file */
- SFCLEAR(&newf, NIL(Vtmutex_t *));
- newf.flags = SF_STATIC;
- newf.mode = SF_AVAIL;
-
- if ((fd = _tmpfd(f)) < 0)
- return -1;
-
- /* make sure that the notify function won't be called here since
- we are only interested in creating the file, not the stream */
- _Sfnotify = 0;
- sf = sfnew(&newf, NIL(void *), (size_t) SF_UNBOUND, fd,
- SF_READ | SF_WRITE);
- _Sfnotify = notifyf;
- if (!sf)
- return -1;
-
- if (newf.mutex) { /* don't need a mutex for this stream */
- vtmtxclrlock(newf.mutex);
- vtmtxclose(newf.mutex);
- newf.mutex = NIL(Vtmutex_t *);
- }
-
- /* make sure that new stream has the same mode */
- if ((m = f->flags & (SF_READ | SF_WRITE)) != (SF_READ | SF_WRITE))
- sfset(sf, ((~m) & (SF_READ | SF_WRITE)), 0);
- sfset(sf, (f->mode & (SF_READ | SF_WRITE)), 1);
-
- /* now remake the old stream into the new image */
- memcpy((void *) (&savf), (void *) f, sizeof(Sfio_t));
- memcpy((void *) f, (void *) sf, sizeof(Sfio_t));
- f->push = savf.push;
- f->pool = savf.pool;
- f->rsrv = savf.rsrv;
- f->proc = savf.proc;
- f->mutex = savf.mutex;
- f->stdio = savf.stdio;
-
- if (savf.data) {
- SFSTRSIZE(&savf);
- if (!(savf.flags & SF_MALLOC))
- (void) sfsetbuf(f, (void *) savf.data, savf.size);
- if (savf.extent > 0)
- (void) sfwrite(f, (void *) savf.data, (size_t) savf.extent);
- (void) sfseek(f, (Sfoff_t) (savf.next - savf.data), 0);
- if ((savf.flags & SF_MALLOC))
- free((void *) savf.data);
- }
-
- /* announce change of status */
- if (notifyf)
- (*notifyf) (f, SF_NEW, f->file);
-
- f->disc = disc->disc;
-
- /* erase all traces of newf */
- newf.data = newf.endb = newf.endr = newf.endw = NIL(uchar *);
- newf.file = -1;
- sfclose(&newf);
-
- return 1;
-}
-
-Sfio_t *sftmp(size_t s)
-{
- Sfio_t *f;
- static Sfdisc_t Tmpdisc =
- { NIL(Sfread_f), NIL(Sfwrite_f), NIL(Sfseek_f), _tmpexcept,
-#if _tmp_rmfail
- &Rmdisc
-#else
- NIL(Sfdisc_t *)
-#endif
- };
-
- /* start with a memory resident stream */
- if (!
- (f =
- sfnew(NIL(Sfio_t *), NIL(char *), s, -1,
- SF_STRING | SF_READ | SF_WRITE)))
- return NIL(Sfio_t *);
-
- if (s != (size_t) SF_UNBOUND) /* set up a discipline for out-of-bound, etc. */
- f->disc = &Tmpdisc;
-
- /* make the file now */
- if (s == 0 && _tmpexcept(f, SF_DPOP, NIL(void *), f->disc) < 0) {
- sfclose(f);
- return NIL(Sfio_t *);
- }
-
- return f;
-}
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