diff options
Diffstat (limited to 'usr/src/lib/libast/common/sfio/sfgetr.c')
| -rw-r--r-- | usr/src/lib/libast/common/sfio/sfgetr.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/usr/src/lib/libast/common/sfio/sfgetr.c b/usr/src/lib/libast/common/sfio/sfgetr.c new file mode 100644 index 0000000000..a3df6757a9 --- /dev/null +++ b/usr/src/lib/libast/common/sfio/sfgetr.c @@ -0,0 +1,163 @@ +/*********************************************************************** +* * +* This software is part of the ast package * +* Copyright (c) 1985-2007 AT&T Knowledge Ventures * +* and is licensed under the * +* Common Public License, Version 1.0 * +* by AT&T Knowledge Ventures * +* * +* A copy of the License is available at * +* http://www.opensource.org/licenses/cpl1.0.txt * +* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) * +* * +* Information and Software Systems Research * +* AT&T Research * +* Florham Park NJ * +* * +* Glenn Fowler <gsf@research.att.com> * +* David Korn <dgk@research.att.com> * +* Phong Vo <kpv@research.att.com> * +* * +***********************************************************************/ +#include "sfhdr.h" + +/* Read a record delineated by a character. +** The record length can be accessed via sfvalue(f). +** +** Written by Kiem-Phong Vo +*/ + +#if __STD_C +char* sfgetr(reg Sfio_t *f, reg int rc, int type) +#else +char* sfgetr(f,rc,type) +reg Sfio_t* f; /* stream to read from */ +reg int rc; /* record separator */ +int type; +#endif +{ + reg ssize_t n, un; + reg uchar *s, *ends, *us; + reg int found; + reg Sfrsrv_t* rsrv; + + SFMTXSTART(f, NIL(char*)); + + if(rc < 0 || (f->mode != SF_READ && _sfmode(f,SF_READ,0) < 0) ) + SFMTXRETURN(f, NIL(char*)); + SFLOCK(f,0); + + /* buffer to be returned */ + rsrv = NIL(Sfrsrv_t*); + us = NIL(uchar*); + un = 0; + found = 0; + + /* compatibility mode */ + type = type < 0 ? SF_LASTR : type == 1 ? SF_STRING : type; + + if(type&SF_LASTR) /* return the broken record */ + { if((rsrv = f->rsrv) && (un = -rsrv->slen) > 0) + { us = rsrv->data; + found = 1; + } + goto done; + } + + while(!found) + { /* fill buffer if necessary */ + if((n = (ends = f->endb) - (s = f->next)) <= 0) + { /* for unseekable devices, peek-read 1 record */ + f->getr = rc; + f->mode |= SF_RC; + + /* fill buffer the conventional way */ + if(SFRPEEK(f,s,n) <= 0) + { us = NIL(uchar*); + goto done; + } + else + { ends = s+n; + if(f->mode&SF_RC) + { s = ends[-1] == rc ? ends-1 : ends; + goto do_copy; + } + } + } + +#if _lib_memchr + if(!(s = (uchar*)memchr((char*)s,rc,n))) + s = ends; +#else + while(*s != rc) + if((s += 1) == ends) + break; +#endif + do_copy: + if(s < ends) /* found separator */ + { s += 1; /* include the separator */ + found = 1; + + if(!us && + (!(type&SF_STRING) || !(f->flags&SF_STRING) || + ((f->flags&SF_STRING) && (f->bits&SF_BOTH) ) ) ) + { /* returning data in buffer */ + us = f->next; + un = s - f->next; + f->next = s; + goto done; + } + } + + /* amount to be read */ + n = s - f->next; + + if(!found && _Sfmaxr > 0 && un+n+1 >= _Sfmaxr) /* already exceed limit */ + { us = NIL(uchar*); + goto done; + } + + /* get internal buffer */ + if(!rsrv || rsrv->size < un+n+1) + { if(rsrv) + rsrv->slen = un; + if((rsrv = _sfrsrv(f,un+n+1)) != NIL(Sfrsrv_t*)) + us = rsrv->data; + else + { us = NIL(uchar*); + goto done; + } + } + + /* now copy data */ + s = us+un; + un += n; + ends = f->next; + f->next += n; + MEMCPY(s,ends,n); + } + +done: + _Sfi = f->val = un; + f->getr = 0; + if(found && rc != 0 && (type&SF_STRING) ) + { us[un-1] = '\0'; + if(us >= f->data && us < f->endb) + { f->getr = rc; + f->mode |= SF_GETR; + } + } + + /* prepare for a call to get the broken record */ + if(rsrv) + rsrv->slen = found ? 0 : -un; + + SFOPEN(f,0); + + if(us && (type&SF_LOCKR) ) + { f->mode |= SF_PEEK|SF_GETR; + f->endr = f->data; + } + + SFMTXRETURN(f, (char*)us); +} |