sh5.c

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#define Extern extern
#include <sys/types.h>
#include <signal.h>
#include <errno.h>
#include <setjmp.h>
#include "sh.h"

/* -------- io.c -------- */
/* #include "sh.h" */

/*
 * shell IO
 */

static struct iobuf sharedbuf = {AFID_NOBUF};
static struct iobuf mainbuf = {AFID_NOBUF};
static unsigned bufid = AFID_ID;        /* buffer id counter */

struct ioarg temparg = {0, 0, 0, AFID_NOBUF, 0};

_PROTOTYPE(static void readhere, (char **name, char *s, int ec ));
_PROTOTYPE(void pushio, (struct ioarg *argp, int (*fn)()));
_PROTOTYPE(static int xxchar, (struct ioarg *ap ));
_PROTOTYPE(void tempname, (char *tname ));

int
getc(ec)
register int ec;
{
        register int c;

        if(e.linep > elinep) {
                while((c=readc()) != '\n' && c)
                        ;
                err("input line too long");
                gflg++;
                return(c);
        }
        c = readc();
        if (ec != '\'' && e.iop->task != XGRAVE) {
                if(c == '\\') {
                        c = readc();
                        if (c == '\n' && ec != '\"')
                                return(getc(ec));
                        c |= QUOTE;
                }
        }
        return(c);
}

void
unget(c)
int c;
{
        if (e.iop >= e.iobase)
                e.iop->peekc = c;
}

int
eofc()

{
  return e.iop < e.iobase || (e.iop->peekc == 0 && e.iop->prev == 0);
}

int
readc()
{
        register c;

        for (; e.iop >= e.iobase; e.iop--)
                if ((c = e.iop->peekc) != '\0') {
                        e.iop->peekc = 0;
                        return(c);
                }
                else {
                    if (e.iop->prev != 0) {
                        if ((c = (*e.iop->iofn)(e.iop->argp, e.iop)) != '\0') {
                                if (c == -1) {
                                        e.iop++;
                                        continue;
                                }
                                if (e.iop == iostack)
                                        ioecho(c);
                                return(e.iop->prev = c);
                        }
                        else if (e.iop->task == XIO && e.iop->prev != '\n') {
                                e.iop->prev = 0;
                                if (e.iop == iostack)
                                        ioecho('\n');
                                return '\n';
                        }
                    }
                    if (e.iop->task == XIO) {
                        if (multiline)
                            return e.iop->prev = 0;
                        if (talking && e.iop == iostack+1)
                            prs(prompt->value);
                    }
                }
        if (e.iop >= iostack)
                return(0);
        leave();
        /* NOTREACHED */
}

void
ioecho(c)
char c;
{
        if (flag['v'])
                write(2, &c, sizeof c);
}

void
pushio(argp, fn)
struct ioarg *argp;
int (*fn)();
{
        if (++e.iop >= &iostack[NPUSH]) {
                e.iop--;
                err("Shell input nested too deeply");
                gflg++;
                return;
        }
        e.iop->iofn = fn;

        if (argp->afid != AFID_NOBUF)
          e.iop->argp = argp;
        else {
          e.iop->argp  = ioargstack + (e.iop - iostack);
          *e.iop->argp = *argp;
          e.iop->argp->afbuf = e.iop == &iostack[0] ? &mainbuf : &sharedbuf;
          if (isatty(e.iop->argp->afile) == 0 &&
              (e.iop == &iostack[0] ||
               lseek(e.iop->argp->afile, 0L, 1) != -1)) {
            if (++bufid == AFID_NOBUF)
              bufid = AFID_ID;
            e.iop->argp->afid  = bufid;
          }
        }

        e.iop->prev  = ~'\n';
        e.iop->peekc = 0;
        e.iop->xchar = 0;
        e.iop->nlcount = 0;
        if (fn == filechar || fn == linechar)
                e.iop->task = XIO;
        else if (fn == gravechar || fn == qgravechar)
                e.iop->task = XGRAVE;
        else
                e.iop->task = XOTHER;
}

struct io *
setbase(ip)
struct io *ip;
{
        register struct io *xp;

        xp = e.iobase;
        e.iobase = ip;
        return(xp);
}

/*
 * Input generating functions
 */

/*
 * Produce the characters of a string, then a newline, then EOF.
 */
int
nlchar(ap)
register struct ioarg *ap;
{
        register int c;

        if (ap->aword == NULL)
                return(0);
        if ((c = *ap->aword++) == 0) {
                ap->aword = NULL;
                return('\n');
        }
        return(c);
}

/*
 * Given a list of words, produce the characters
 * in them, with a space after each word.
 */
int
wdchar(ap)
register struct ioarg *ap;
{
        register char c;
        register char **wl;

        if ((wl = ap->awordlist) == NULL)
                return(0);
        if (*wl != NULL) {
                if ((c = *(*wl)++) != 0)
                        return(c & 0177);
                ap->awordlist++;
                return(' ');
        }
        ap->awordlist = NULL;
        return('\n');
}

/*
 * Return the characters of a list of words,
 * producing a space between them.
 */
int
dolchar(ap)
register struct ioarg *ap;
{
        register char *wp;

        if ((wp = *ap->awordlist++) != NULL) {
                PUSHIO(aword, wp, *ap->awordlist == NULL? strchar: xxchar);
                return(-1);
        }
        return(0);
}

static int
xxchar(ap)
register struct ioarg *ap;
{
        register int c;

        if (ap->aword == NULL)
                return(0);
        if ((c = *ap->aword++) == '\0') {
                ap->aword = NULL;
                return(' ');
        }
        return(c);
}

/*
 * Produce the characters from a single word (string).
 */
int
strchar(ap)
register struct ioarg *ap;
{
        register int c;

        if (ap->aword == NULL || (c = *ap->aword++) == 0)
                return(0);
        return(c);
}

/*
 * Produce quoted characters from a single word (string).
 */
int
qstrchar(ap)
register struct ioarg *ap;
{
        register int c;

        if (ap->aword == NULL || (c = *ap->aword++) == 0)
                return(0);
        return(c|QUOTE);
}

/*
 * Return the characters from a file.
 */
int
filechar(ap)
register struct ioarg *ap;
{
        register int i;
        char c;
        struct iobuf *bp = ap->afbuf;

        if (ap->afid != AFID_NOBUF) {
          if ((i = ap->afid != bp->id) || bp->bufp == bp->ebufp) {
            if (i)
              lseek(ap->afile, ap->afpos, 0);
            do {
              i = read(ap->afile, bp->buf, sizeof(bp->buf));
            } while (i < 0 && errno == EINTR);
            if (i <= 0) {
              closef(ap->afile);
              return 0;
            }
            bp->id = ap->afid;
            bp->ebufp = (bp->bufp  = bp->buf) + i;
          }
          ap->afpos++;
          return *bp->bufp++ & 0177;
        }

        do {
                i = read(ap->afile, &c, sizeof(c));
        } while (i < 0 && errno == EINTR);
        return(i == sizeof(c)? c&0177: (closef(ap->afile), 0));
}

/*
 * Return the characters from a here temp file.
 */
int
herechar(ap)
register struct ioarg *ap;
{
        char c;


        if (read(ap->afile, &c, sizeof(c)) != sizeof(c)) {
                close(ap->afile);
                c = 0;
        }
        return (c);

}

/*
 * Return the characters produced by a process (`...`).
 * Quote them if required, and remove any trailing newline characters.
 */
int
gravechar(ap, iop)
struct ioarg *ap;
struct io *iop;
{
        register int c;

        if ((c = qgravechar(ap, iop)&~QUOTE) == '\n')
                c = ' ';
        return(c);
}

int
qgravechar(ap, iop)
register struct ioarg *ap;
struct io *iop;
{
        register int c;

        if (iop->xchar) {
                if (iop->nlcount) {
                        iop->nlcount--;
                        return('\n'|QUOTE);
                }
                c = iop->xchar;
                iop->xchar = 0;
        } else if ((c = filechar(ap)) == '\n') {
                iop->nlcount = 1;
                while ((c = filechar(ap)) == '\n')
                        iop->nlcount++;
                iop->xchar = c;
                if (c == 0)
                        return(c);
                iop->nlcount--;
                c = '\n';
        }
        return(c!=0? c|QUOTE: 0);
}

/*
 * Return a single command (usually the first line) from a file.
 */
int
linechar(ap)
register struct ioarg *ap;
{
        register int c;

        if ((c = filechar(ap)) == '\n') {
                if (!multiline) {
                        closef(ap->afile);
                        ap->afile = -1; /* illegal value */
                }
        }
        return(c);
}

void
prs(s)
register char *s;
{
        if (*s)
                write(2, s, strlen(s));
}

void
putc(c)
char c;
{
        write(2, &c, sizeof c);
}

void
prn(u)
unsigned u;
{
        prs(itoa(u, 0));
}

void
closef(i)
register int i;
{
        if (i > 2)
                close(i);
}

void
closeall()
{
        register u;

        for (u=NUFILE; u<NOFILE;)
                close(u++);
}

/*
 * remap fd into Shell's fd space
 */
int
remap(fd)
register int fd;
{
        register int i;
        int map[NOFILE];

        if (fd < e.iofd) {
                for (i=0; i<NOFILE; i++)
                        map[i] = 0;
                do {
                        map[fd] = 1;
                        fd = dup(fd);
                } while (fd >= 0 && fd < e.iofd);
                for (i=0; i<NOFILE; i++)
                        if (map[i])
                                close(i);
                if (fd < 0)
                        err("too many files open in shell");
        }
        return(fd);
}

int
openpipe(pv)
register int *pv;
{
        register int i;

        if ((i = pipe(pv)) < 0)
                err("can't create pipe - try again");
        return(i);
}

void
closepipe(pv)
register int *pv;
{
        if (pv != NULL) {
                close(*pv++);
                close(*pv);
        }
}

/* -------- here.c -------- */
/* #include "sh.h" */

/*
 * here documents
 */

struct  here {
        char    *h_tag;
        int     h_dosub;
        struct  ioword *h_iop;
        struct  here    *h_next;
};

static  struct here *inhere;            /* list of hear docs while parsing */
static  struct here *acthere;           /* list of active here documents */

void
inithere()
{
        inhere=acthere=(struct here*)0;
}

void
markhere(s, iop)
register char *s;
struct ioword *iop;
{
        register struct here *h, *lh;

        h = (struct here *) space(sizeof(struct here));
        if (h == 0)
                return;
        h->h_tag = evalstr(s, DOSUB);
        if (h->h_tag == 0)
                return;
        h->h_iop = iop;
        iop->io_name = 0;
        h->h_next = NULL;
        if (inhere == 0)
                inhere = h;
        else
                for (lh = inhere; lh!=NULL; lh = lh->h_next)
                        if (lh->h_next == 0) {
                                lh->h_next = h;
                                break;
                        }
        iop->io_flag |= IOHERE|IOXHERE;
        for (s = h->h_tag; *s; s++)
                if (*s & QUOTE) {
                        iop->io_flag &= ~ IOXHERE;
                        *s &= ~ QUOTE;
                }
        h->h_dosub = iop->io_flag & IOXHERE;
}

void
gethere()
{
        register struct here *h, *hp;

        /* Scan here files first leaving inhere list in place */
        for (hp = h = inhere; h != NULL; hp = h, h = h->h_next)
          readhere(&h->h_iop->io_name, h->h_tag, h->h_dosub? 0: '\'');

        /* Make inhere list active - keep list intact for scraphere */
        if (hp != NULL) {
          hp->h_next = acthere;
          acthere    = inhere;
          inhere     = NULL;
        }
}

static void
readhere(name, s, ec)
char **name;
register char *s;
int ec;
{
        int tf;
        char tname[30];
        register c;
        jmp_buf ev;
        char line [LINELIM+1];
        char *next;

        tempname(tname);
        *name = strsave(tname, areanum);
        tf = creat(tname, 0600);
        if (tf < 0)
                return;
        if (newenv(setjmp(errpt = ev)) != 0)
                unlink(tname);
        else {
                pushio(e.iop->argp, e.iop->iofn);
                e.iobase = e.iop;
                for (;;) {
                        if (talking && e.iop <= iostack)
                                prs(cprompt->value);
                        next = line;
                        while ((c = readc()) != '\n' && c) {
                                if (next >= &line[LINELIM]) {
                                        c = 0;
                                        break;
                                }
                                *next++ = c;
                        }
                        *next = 0;
                        if (strcmp(s, line) == 0 || c == 0)
                                break;
                        *next++ = '\n';
                        write (tf, line, (int)(next-line));
                }
                if (c == 0) {
                        prs("here document `"); prs(s); err("' unclosed");
                }
                quitenv();
        }
        close(tf);
}

/*
 * open here temp file.
 * if unquoted here, expand here temp file into second temp file.
 */
int
herein(hname, xdoll)
char *hname;
int xdoll;
{
        register hf, tf;

        if (hname == 0)
                return(-1);
        hf = open(hname, 0);
        if (hf < 0)
                return (-1);
        if (xdoll) {
                char c;
                char tname[30];
                jmp_buf ev;

                tempname(tname);
                if ((tf = creat(tname, 0600)) < 0)
                        return (-1);
                if (newenv(setjmp(errpt = ev)) == 0) {
                        PUSHIO(afile, hf, herechar);
                        setbase(e.iop);
                        while ((c = subgetc(0, 0)) != 0) {
                                char c1 = c&~QUOTE;

                                if (c&QUOTE && !any(c1,"`$\\"))
                                        write(tf,"\\",1);
                                write(tf, &c1, 1);
                        }
                        quitenv();
                } else
                        unlink(tname);
                close(tf);
                tf = open(tname, 0);
                unlink(tname);
                return (tf);
        } else
                return (hf);
}

void
scraphere()
{
        register struct here *h;

        for (h = inhere; h != NULL; h = h->h_next) {
                if (h->h_iop && h->h_iop->io_name)
                  unlink(h->h_iop->io_name);
        }
        inhere = NULL;
}

/* unlink here temp files before a freearea(area) */
void
freehere(area)
int area;
{
        register struct here *h, *hl;

        hl = NULL;
        for (h = acthere; h != NULL; h = h->h_next)
                if (getarea((char *) h) >= area) {
                        if (h->h_iop->io_name != NULL)
                                unlink(h->h_iop->io_name);
                        if (hl == NULL)
                                acthere = h->h_next;
                        else
                                hl->h_next = h->h_next;
                } else
                        hl = h;
}

void
tempname(tname)
char *tname;
{
        static int inc;
        register char *cp, *lp;

        for (cp = tname, lp = "/tmp/shtm"; (*cp = *lp++) != '\0'; cp++)
                ;
        lp = putn(getpid()*1000 + inc++);
        for (; (*cp = *lp++) != '\0'; cp++)
                ;
}

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