read.c revision 3f54fd611f536639ec30dd53c48e5ec1897cc7d9
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1982-2012 AT&T Intellectual Property *
* and is licensed under the *
* Eclipse Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.eclipse.org/org/documents/epl-v10.html *
* (with md5 checksum b35adb5213ca9657e911e9befb180842) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* David Korn <dgk@research.att.com> *
* *
***********************************************************************/
#pragma prototyped
/*
* read [-ACprs] [-d delim] [-u filenum] [-t timeout] [-n n] [-N n] [name...]
*
* David Korn
* AT&T Labs
*
*/
#include <ast.h>
#include <error.h>
#include "defs.h"
#include "variables.h"
#include "lexstates.h"
#include "io.h"
#include "name.h"
#include "builtins.h"
#include "history.h"
#include "terminal.h"
#include "edit.h"
#define R_FLAG 1 /* raw mode */
#define S_FLAG 2 /* save in history file */
#define A_FLAG 4 /* read into array */
#define N_FLAG 8 /* fixed size read at most */
#define NN_FLAG 0x10 /* fixed size read exact */
#define V_FLAG 0x20 /* use default value */
#define C_FLAG 0x40 /* read into compound variable */
#define D_FLAG 8 /* must be number of bits for all flags */
#define SS_FLAG 0x80 /* read .csv format file */
struct read_save
{
char **argv;
char *prompt;
short fd;
short plen;
int flags;
ssize_t len;
long timeout;
};
int b_read(int argc,char *argv[], Shbltin_t *context)
{
Sfdouble_t sec;
register char *name;
register int r, flags=0, fd=0;
register Shell_t *shp = context->shp;
ssize_t len=0;
long timeout = 1000*shp->st.tmout;
int save_prompt, fixargs=context->invariant;
struct read_save *rp;
static char default_prompt[3] = {ESC,ESC};
rp = (struct read_save*)(context->data);
if(argc==0)
{
if(rp)
free((void*)rp);
return(0);
}
if(rp)
{
flags = rp->flags;
timeout = rp->timeout;
fd = rp->fd;
argv = rp->argv;
name = rp->prompt;
r = rp->plen;
goto bypass;
}
while((r = optget(argv,sh_optread))) switch(r)
{
case 'A':
flags |= A_FLAG;
break;
case 'C':
flags |= C_FLAG;
break;
case 't':
sec = sh_strnum(opt_info.arg, (char**)0,1);
timeout = sec ? 1000*sec : 1;
break;
case 'd':
if(opt_info.arg && *opt_info.arg!='\n')
{
char *cp = opt_info.arg;
flags &= ~((1<<D_FLAG)-1);
flags |= (mbchar(cp)<< D_FLAG);
}
break;
case 'p':
if((fd = shp->cpipe[0])<=0)
errormsg(SH_DICT,ERROR_exit(1),e_query);
break;
case 'n': case 'N':
flags &= ((1<<D_FLAG)-1);
flags |= (r=='n'?N_FLAG:NN_FLAG);
len = opt_info.num;
break;
case 'r':
flags |= R_FLAG;
break;
case 's':
/* save in history file */
flags |= S_FLAG;
break;
case 'S':
flags |= SS_FLAG;
break;
case 'u':
fd = (int)opt_info.num;
if(sh_inuse(shp,fd))
fd = -1;
break;
case 'v':
flags |= V_FLAG;
break;
case ':':
errormsg(SH_DICT,2, "%s", opt_info.arg);
break;
case '?':
errormsg(SH_DICT,ERROR_usage(2), "%s", opt_info.arg);
break;
}
argv += opt_info.index;
if(error_info.errors)
errormsg(SH_DICT,ERROR_usage(2), "%s", optusage((char*)0));
if(!((r=shp->fdstatus[fd])&IOREAD) || !(r&(IOSEEK|IONOSEEK)))
r = sh_iocheckfd(shp,fd);
if(fd<0 || !(r&IOREAD))
errormsg(SH_DICT,ERROR_system(1),e_file+4);
/* look for prompt */
if((name = *argv) && (name=strchr(name,'?')) && (r&IOTTY))
r = strlen(name++);
else
r = 0;
if(argc==fixargs && (rp=newof(NIL(struct read_save*),struct read_save,1,0)))
{
context->data = (void*)rp;
rp->fd = fd;
rp->flags = flags;
rp->timeout = timeout;
rp->argv = argv;
rp->prompt = name;
rp->plen = r;
rp->len = len;
}
bypass:
shp->prompt = default_prompt;
if(r && (shp->prompt=(char*)sfreserve(sfstderr,r,SF_LOCKR)))
{
memcpy(shp->prompt,name,r);
sfwrite(sfstderr,shp->prompt,r-1);
}
shp->timeout = 0;
save_prompt = shp->nextprompt;
shp->nextprompt = 0;
r=sh_readline(shp,argv,fd,flags,len,timeout);
shp->nextprompt = save_prompt;
if(r==0 && (r=(sfeof(shp->sftable[fd])||sferror(shp->sftable[fd]))))
{
if(fd == shp->cpipe[0] && errno!=EINTR)
sh_pclose(shp->cpipe);
}
return(r);
}
/*
* here for read timeout
*/
static void timedout(void *handle)
{
sfclrlock((Sfio_t*)handle);
sh_exit(1);
}
/*
* This is the code to read a line and to split it into tokens
* <names> is an array of variable names
* <fd> is the file descriptor
* <flags> is union of -A, -r, -s, and contains delimiter if not '\n'
* <timeout> is number of milli-seconds until timeout
*/
int sh_readline(register Shell_t *shp,char **names, volatile int fd, int flags,ssize_t size,long timeout)
{
register ssize_t c;
register unsigned char *cp;
register Namval_t *np;
register char *name, *val;
register Sfio_t *iop;
Namfun_t *nfp;
char *ifs;
unsigned char *cpmax;
unsigned char *del;
char was_escape = 0;
char use_stak = 0;
volatile char was_write = 0;
volatile char was_share = 1;
volatile int keytrap;
int rel, wrd;
long array_index = 0;
void *timeslot=0;
int delim = '\n';
int jmpval=0;
int binary;
int oflags=NV_ASSIGN|NV_VARNAME;
char inquote = 0;
struct checkpt buff;
Edit_t *ep = (struct edit*)shp->gd->ed_context;
if(!(iop=shp->sftable[fd]) && !(iop=sh_iostream(shp,fd)))
return(1);
sh_stats(STAT_READS);
if(names && (name = *names))
{
Namval_t *mp;
if(val= strchr(name,'?'))
*val = 0;
if(flags&C_FLAG)
oflags |= NV_ARRAY;
np = nv_open(name,shp->var_tree,oflags);
if(np && nv_isarray(np) && (mp=nv_opensub(np)))
np = mp;
if((flags&V_FLAG) && shp->gd->ed_context)
((struct edit*)shp->gd->ed_context)->e_default = np;
if(flags&A_FLAG)
{
Namarr_t *ap;
flags &= ~A_FLAG;
array_index = 1;
if((ap=nv_arrayptr(np)) && !ap->fun)
ap->nelem++;
nv_unset(np);
if((ap=nv_arrayptr(np)) && !ap->fun)
ap->nelem--;
nv_putsub(np,NIL(char*),0L);
}
else if(flags&C_FLAG)
{
char *sp = np->nvenv;
delim = -1;
nv_unset(np);
if(!nv_isattr(np,NV_MINIMAL))
np->nvenv = sp;
nv_setvtree(np);
}
else
name = *++names;
if(val)
*val = '?';
}
else
{
name = 0;
if(dtvnext(shp->var_tree) || shp->namespace)
np = nv_open(nv_name(REPLYNOD),shp->var_tree,0);
else
np = REPLYNOD;
}
keytrap = ep?ep->e_keytrap:0;
if(size || (flags>>D_FLAG)) /* delimiter not new-line or fixed size read */
{
if((shp->fdstatus[fd]&IOTTY) && !keytrap)
tty_raw(fd,1);
if(!(flags&(N_FLAG|NN_FLAG)))
{
delim = ((unsigned)flags)>>D_FLAG;
ep->e_nttyparm.c_cc[VEOL] = delim;
ep->e_nttyparm.c_lflag |= ISIG;
tty_set(fd,TCSADRAIN,&ep->e_nttyparm);
}
}
binary = nv_isattr(np,NV_BINARY);
if(!binary && !(flags&(N_FLAG|NN_FLAG)))
{
Namval_t *mp;
/* set up state table based on IFS */
ifs = nv_getval(mp=sh_scoped(shp,IFSNOD));
if((flags&R_FLAG) && shp->ifstable['\\']==S_ESC)
shp->ifstable['\\'] = 0;
else if(!(flags&R_FLAG) && shp->ifstable['\\']==0)
shp->ifstable['\\'] = S_ESC;
if(delim>0)
shp->ifstable[delim] = S_NL;
if(delim!='\n')
{
shp->ifstable['\n'] = 0;
nv_putval(mp, ifs, NV_RDONLY);
}
shp->ifstable[0] = S_EOF;
if((flags&SS_FLAG))
{
shp->ifstable['"'] = S_QUOTE;
shp->ifstable['\r'] = S_ERR;
}
}
sfclrerr(iop);
for(nfp=np->nvfun; nfp; nfp = nfp->next)
{
if(nfp->disc && nfp->disc->readf)
{
Namval_t *mp = nv_open(name,shp->var_tree,oflags|NV_NOREF);
if((c=(*nfp->disc->readf)(mp,iop,delim,nfp))>=0)
return(c);
}
}
if(binary && !(flags&(N_FLAG|NN_FLAG)))
{
flags |= NN_FLAG;
size = nv_size(np);
}
was_write = (sfset(iop,SF_WRITE,0)&SF_WRITE)!=0;
if(fd==0)
was_share = (sfset(iop,SF_SHARE,shp->redir0!=2)&SF_SHARE)!=0;
if(timeout || (shp->fdstatus[fd]&(IOTTY|IONOSEEK)))
{
sh_pushcontext(shp,&buff,1);
jmpval = sigsetjmp(buff.buff,0);
if(jmpval)
goto done;
if(timeout)
timeslot = (void*)sh_timeradd(timeout,0,timedout,(void*)iop);
}
if(flags&(N_FLAG|NN_FLAG))
{
char buf[256],*var=buf,*cur,*end,*up,*v;
/* reserved buffer */
if((c=size)>=sizeof(buf))
{
if(!(var = (char*)malloc(c+1)))
sh_exit(1);
end = var + c;
}
else
end = var + sizeof(buf) - 1;
up = cur = var;
if((sfset(iop,SF_SHARE,1)&SF_SHARE) && fd!=0)
was_share = 1;
if(size==0)
{
cp = sfreserve(iop,0,0);
c = 0;
}
else
{
ssize_t m;
int f;
for (;;)
{
c = size;
if(keytrap)
{
cp = 0;
f = 0;
m = 0;
while(c-->0 && (buf[m]=ed_getchar(ep,0)))
m++;
if(m>0)
cp = (unsigned char*)buf;
}
else
{
f = 1;
if(cp = sfreserve(iop,c,SF_LOCKR))
m = sfvalue(iop);
else if(flags&NN_FLAG)
{
c = size;
m = (cp = sfreserve(iop,c,0)) ? sfvalue(iop) : 0;
f = 0;
}
else
{
c = sfvalue(iop);
m = (cp = sfreserve(iop,c,SF_LOCKR)) ? sfvalue(iop) : 0;
}
}
if(m>0 && (flags&N_FLAG) && !binary && (v=memchr(cp,'\n',m)))
{
*v++ = 0;
m = v-(char*)cp;
}
if((c=m)>size)
c = size;
if(c>0)
{
if(c > (end-cur))
{
ssize_t cx = cur - var, ux = up - var;
m = (end - var) + (c - (end - cur));
if (var == buf)
{
v = (char*)malloc(m+1);
var = memcpy(v, var, cur - var);
}
else
var = newof(var, char, m, 1);
end = var + m;
cur = var + cx;
up = var + ux;
}
if(cur!=(char*)cp)
memcpy((void*)cur,cp,c);
if(f)
sfread(iop,cp,c);
cur += c;
#if SHOPT_MULTIBYTE
if(!binary && mbwide())
{
int x;
int z;
mbinit();
*cur = 0;
x = z = 0;
while (up < cur && (z = mbsize(up)) > 0)
{
up += z;
x++;
}
if((size -= x) > 0 && (up >= cur || z < 0) && ((flags & NN_FLAG) || z < 0 || m > c))
continue;
}
#endif
}
#if SHOPT_MULTIBYTE
if(!binary && mbwide() && (up == var || (flags & NN_FLAG) && size))
cur = var;
#endif
*cur = 0;
if(c>=size || (flags&N_FLAG) || m==0)
{
if(m)
sfclrerr(iop);
break;
}
size -= c;
}
}
if(timeslot)
timerdel(timeslot);
if(binary && !((size=nv_size(np)) && nv_isarray(np) && c!=size))
{
if((c==size) && np->nvalue.cp && !nv_isarray(np))
memcpy((char*)np->nvalue.cp,var,c);
else
{
Namval_t *mp;
if(var==buf)
var = memdup(var,c+1);
nv_putval(np,var,NV_RAW);
nv_setsize(np,c);
if(!nv_isattr(np,NV_IMPORT|NV_EXPORT) && (mp=(Namval_t*)np->nvenv))
nv_setsize(mp,c);
}
}
else
{
nv_putval(np,var,0);
if(var!=buf)
free((void*)var);
}
goto done;
}
else if(cp = (unsigned char*)sfgetr(iop,delim,0))
c = sfvalue(iop);
else if(cp = (unsigned char*)sfgetr(iop,delim,-1))
{
c = sfvalue(iop)+1;
if(!sferror(iop) && sfgetc(iop) >=0)
errormsg(SH_DICT,ERROR_exit(1),e_overlimit,"line length");
}
if(timeslot)
timerdel(timeslot);
if((flags&S_FLAG) && !shp->gd->hist_ptr)
{
sh_histinit((void*)shp);
if(!shp->gd->hist_ptr)
flags &= ~S_FLAG;
}
if(cp)
{
cpmax = cp + c;
#if SHOPT_CRNL
if(delim=='\n' && c>=2 && cpmax[-2]=='\r')
cpmax--;
#endif /* SHOPT_CRNL */
if(*(cpmax-1) != delim)
*(cpmax-1) = delim;
if(flags&S_FLAG)
sfwrite(shp->gd->hist_ptr->histfp,(char*)cp,c);
c = shp->ifstable[*cp++];
#if !SHOPT_MULTIBYTE
if(!name && (flags&R_FLAG)) /* special case single argument */
{
/* skip over leading blanks */
while(c==S_SPACE)
c = shp->ifstable[*cp++];
/* strip trailing delimiters */
if(cpmax[-1] == '\n')
cpmax--;
if(cpmax>cp)
{
while((c=shp->ifstable[*--cpmax])==S_DELIM || c==S_SPACE);
cpmax[1] = 0;
}
else
*cpmax =0;
if(nv_isattr(np, NV_RDONLY))
{
errormsg(SH_DICT,ERROR_warn(0),e_readonly, nv_name(np));
jmpval = 1;
}
else
nv_putval(np,(char*)cp-1,0);
goto done;
}
#endif /* !SHOPT_MULTIBYTE */
}
else
c = S_NL;
shp->nextprompt = 2;
rel= staktell();
/* val==0 at the start of a field */
val = 0;
del = 0;
while(1)
{
switch(c)
{
#if SHOPT_MULTIBYTE
case S_MBYTE:
if(val==0)
val = (char*)(cp-1);
if(sh_strchr(ifs,(char*)cp-1)>=0)
{
c = mbsize((char*)cp-1);
if(name)
cp[-1] = 0;
if(c>1)
cp += (c-1);
c = S_DELIM;
}
else
c = 0;
continue;
#endif /*SHOPT_MULTIBYTE */
case S_QUOTE:
c = shp->ifstable[*cp++];
inquote = !inquote;
if(val)
{
stakputs(val);
use_stak = 1;
*val = 0;
}
continue;
case S_ESC:
/* process escape character */
if((c = shp->ifstable[*cp++]) == S_NL)
was_escape = 1;
else
c = 0;
if(val)
{
stakputs(val);
use_stak = 1;
was_escape = 1;
*val = 0;
}
continue;
case S_ERR:
cp++;
case S_EOF:
/* check for end of buffer */
if(val && *val)
{
stakputs(val);
use_stak = 1;
}
val = 0;
if(cp>=cpmax)
{
c = S_NL;
break;
}
/* eliminate null bytes */
c = shp->ifstable[*cp++];
if(!name && val && (c==S_SPACE||c==S_DELIM||c==S_MBYTE))
c = 0;
continue;
case S_NL:
if(was_escape)
{
was_escape = 0;
if(cp = (unsigned char*)sfgetr(iop,delim,0))
c = sfvalue(iop);
else if(cp=(unsigned char*)sfgetr(iop,delim,-1))
c = sfvalue(iop)+1;
if(cp)
{
if(flags&S_FLAG)
sfwrite(shp->gd->hist_ptr->histfp,(char*)cp,c);
cpmax = cp + c;
c = shp->ifstable[*cp++];
val=0;
if(!name && (c==S_SPACE || c==S_DELIM || c==S_MBYTE))
c = 0;
continue;
}
}
c = S_NL;
break;
case S_SPACE:
/* skip over blanks */
while((c=shp->ifstable[*cp++])==S_SPACE);
if(!val)
continue;
#if SHOPT_MULTIBYTE
if(c==S_MBYTE)
{
if(sh_strchr(ifs,(char*)cp-1)>=0)
{
if((c = mbsize((char*)cp-1))>1)
cp += (c-1);
c = S_DELIM;
}
else
c = 0;
}
#endif /* SHOPT_MULTIBYTE */
if(c!=S_DELIM)
break;
/* FALL THRU */
case S_DELIM:
if(!del)
del = cp - 1;
if(name)
{
/* skip over trailing blanks */
while((c=shp->ifstable[*cp++])==S_SPACE);
break;
}
/* FALL THRU */
case 0:
if(val==0 || was_escape)
{
val = (char*)(cp-1);
was_escape = 0;
}
/* skip over word characters */
wrd = -1;
while(1)
{
while((c=shp->ifstable[*cp++])==0)
if(!wrd)
wrd = 1;
if(inquote)
{
if(c==S_QUOTE)
{
if(shp->ifstable[*cp]==S_QUOTE)
{
if(val)
{
stakwrite(val,cp-(unsigned char*)val);
use_stak = 1;
}
val = (char*)++cp;
}
else
break;
}
if(c && c!=S_EOF)
{
if(c==S_NL)
{
if(val)
{
stakwrite(val,cp-(unsigned char*)val);
use_stak=1;
}
if(cp = (unsigned char*)sfgetr(iop,delim,0))
c = sfvalue(iop);
else if(cp = (unsigned char*)sfgetr(iop,delim,-1))
c = sfvalue(iop)+1;
val = (char*)cp;
}
continue;
}
}
if(!del&&c==S_DELIM)
del = cp - 1;
if(name || c==S_NL || c==S_ESC || c==S_EOF || c==S_MBYTE)
break;
if(wrd<0)
wrd = 0;
}
if(wrd>0)
del = (unsigned char*)"";
if(c!=S_MBYTE)
cp[-1] = 0;
continue;
}
/* assign value and advance to next variable */
if(!val)
val = "";
if(use_stak)
{
stakputs(val);
stakputc(0);
val = stakptr(rel);
}
if(!name && *val)
{
/* strip off trailing space delimiters */
register unsigned char *vp = (unsigned char*)val + strlen(val);
while(shp->ifstable[*--vp]==S_SPACE);
if(vp==del)
{
if(vp==(unsigned char*)val)
vp--;
else
while(shp->ifstable[*--vp]==S_SPACE);
}
vp[1] = 0;
}
if(nv_isattr(np, NV_RDONLY))
{
errormsg(SH_DICT,ERROR_warn(0),e_readonly, nv_name(np));
jmpval = 1;
}
else
nv_putval(np,val,0);
val = 0;
del = 0;
if(use_stak)
{
stakseek(rel);
use_stak = 0;
}
if(array_index)
{
nv_putsub(np, NIL(char*), array_index++);
if(c!=S_NL)
continue;
name = *++names;
}
while(1)
{
if(sh_isoption(SH_ALLEXPORT)&&!strchr(nv_name(np),'.') && !nv_isattr(np,NV_EXPORT))
{
nv_onattr(np,NV_EXPORT);
sh_envput(shp->env,np);
}
if(name)
{
nv_close(np);
np = nv_open(name,shp->var_tree,NV_NOASSIGN|NV_VARNAME);
name = *++names;
}
else
np = 0;
if(c!=S_NL)
break;
if(!np)
goto done;
if(nv_isattr(np, NV_RDONLY))
{
errormsg(SH_DICT,ERROR_warn(0),e_readonly, nv_name(np));
jmpval = 1;
}
else
nv_putval(np, "", 0);
}
}
done:
if(timeout || (shp->fdstatus[fd]&(IOTTY|IONOSEEK)))
sh_popcontext(shp,&buff);
if(was_write)
sfset(iop,SF_WRITE,1);
if(!was_share)
sfset(iop,SF_SHARE,0);
nv_close(np);
if((shp->fdstatus[fd]&IOTTY) && !keytrap)
tty_cooked(fd);
if(flags&S_FLAG)
hist_flush(shp->gd->hist_ptr);
if(jmpval > 1)
siglongjmp(*shp->jmplist,jmpval);
return(jmpval);
}