Added ignoreeof flag which requires explicit quit instead of

[unix-history] / usr / src / usr.bin / mail / lex.c

#

#include "rcv.h"

/*
* Mail -- a mail program
*
* Lexical processing of commands.
*/

static char *SccsId = "@(#)lex.c        1.2 %G%";

/*
* Interpret user commands one by one.  If standard input is not a tty,
* print no prompt.
*/

int     *msgvec;

commands()
{
       int prompt, firstsw, stop();
       register int n;
       char linebuf[LINESIZE];

       msgvec = (int *) calloc((unsigned) (msgCount + 1), sizeof *msgvec);
       if (rcvmode)
               if (signal(SIGINT, SIG_IGN) == SIG_DFL)
                       signal(SIGINT, stop);
       input = stdin;
       prompt = 1;
       if (!intty)
               prompt = 0;
       firstsw = 1;
       for (;;) {
               setexit();
               if (firstsw > 0) {
                       firstsw = 0;
                       source1(mailrc);
                       if (!nosrc)
                               source1(MASTER);
               }

               /*
                * How's this for obscure:  after we
                * finish sourcing for the first time,
                * go off and print the headers!
                */

               if (firstsw == 0 && !sourcing) {
                       firstsw = -1;
                       if (rcvmode)
                               announce();
               }

               /*
                * Print the prompt, if needed.  Clear out
                * string space, and flush the output.
                */

               if (!rcvmode && !sourcing)
                       return;
top:
               if (prompt && !sourcing)
                       printf("_\r");
               flush();
               sreset();

               /*
                * Read a line of commands from the current input
                * and handle end of file specially.
                */

               n = 0;
               for (;;) {
                       if (readline(input, &linebuf[n]) <= 0) {
                               if (n != 0)
                                       break;
                               if (sourcing) {
                                       unstack();
                                       goto more;
                               }
                               if (value("ignoreeof") != NOSTR && prompt) {
                                       printf("Use \"quit\" to quit.\n");
                                       goto top;
                               }
                               if (!edit) {
                                       signal(SIGINT, SIG_IGN);
                                       return;
                               }
                               edstop();
                               return;
                       }
                       if ((n = strlen(linebuf)) == 0)
                               break;
                       n--;
                       if (linebuf[n] != '\\')
                               break;
                       linebuf[n++] = ' ';
               }
               if (execute(linebuf))
                       return;
more:           ;
       }
}

/*
* Execute a single command.  If the command executed
* is "quit," then return non-zero so that the caller
* will know to return back to main, if he cares.
*/

execute(linebuf)
       char linebuf[];
{
       char word[LINESIZE];
       char *arglist[MAXARGC];
       struct cmd *com;
       register char *cp, *cp2;
       register int c;
       int edstop(), e;

       /*
        * Strip the white space away from the beginning
        * of the command, then scan out a word, which
        * consists of anything except digits and white space.
        *
        * Handle ! escapes differently to get the correct
        * lexical conventions.
        */

       cp = linebuf;
       while (any(*cp, " \t"))
               cp++;
       if (*cp == '!') {
               if (sourcing) {
                       printf("Can't \"!\" while sourcing\n");
                       unstack();
                       return(0);
               }
               shell(cp+1);
               return(0);
       }
       cp2 = word;
       while (*cp && !any(*cp, " \t0123456789$^.-+*'\""))
               *cp2++ = *cp++;
       *cp2 = '\0';

       /*
        * Look up the command; if not found, bitch.
        * Normally, a blank command would map to the
        * first command in the table; while sourcing,
        * however, we ignore blank lines to eliminate
        * confusion.
        */

       if (sourcing && equal(word, ""))
               return(0);
       com = lex(word);
       if (com == NONE) {
               printf("What?\n");
               if (sourcing)
                       unstack();
               return(0);
       }

       /*
        * Special case so that quit causes a return to
        * main, who will call the quit code directly.
        * If we are in a source file, just unstack.
        */

       if (com->c_func == edstop && sourcing) {
               unstack();
               return(0);
       }
       if (!edit && com->c_func == edstop) {
               signal(SIGINT, SIG_IGN);
               return(1);
       }

       /*
        * Process the arguments to the command, depending
        * on the type he expects.  Default to an error.
        * If we are sourcing an interactive command, it's
        * an error.
        */

       if (!rcvmode && (com->c_argtype & M) == 0) {
               printf("May not execute \"%s\" while sending\n",
                   com->c_name);
               unstack();
               return(0);
       }
       if (sourcing && com->c_argtype & I) {
               printf("May not execute \"%s\" while sourcing\n",
                   com->c_name);
               unstack();
               return(0);
       }
       e = 1;
       switch (com->c_argtype & ~(P|I|M)) {
       case MSGLIST:
               /*
                * A message list defaulting to nearest forward
                * legal message.
                */
               if ((c = getmsglist(cp, msgvec, com->c_msgflag)) < 0)
                       break;
               if (c  == 0) {
                       *msgvec = first(com->c_msgflag,
                               com->c_msgmask);
                       msgvec[1] = NULL;
               }
               if (*msgvec == NULL) {
                       printf("No applicable messages\n");
                       break;
               }
               e = (*com->c_func)(msgvec);
               break;

       case NDMLIST:
               /*
                * A message list with no defaults, but no error
                * if none exist.
                */
               if (getmsglist(cp, msgvec, com->c_msgflag) < 0)
                       break;
               e = (*com->c_func)(msgvec);
               break;

       case STRLIST:
               /*
                * Just the straight string, with
                * leading blanks removed.
                */
               while (any(*cp, " \t"))
                       cp++;
               e = (*com->c_func)(cp);
               break;

       case RAWLIST:
               /*
                * A vector of strings, in shell style.
                */
               if ((c = getrawlist(cp, arglist)) < 0)
                       break;
               if (c < com->c_minargs) {
                       printf("%s requires at least %d arg(s)\n",
                               com->c_name, com->c_minargs);
                       break;
               }
               if (c > com->c_maxargs) {
                       printf("%s takes no more than %d arg(s)\n",
                               com->c_name, com->c_maxargs);
                       break;
               }
               e = (*com->c_func)(arglist);
               break;

       case NOLIST:
               /*
                * Just the constant zero, for exiting,
                * eg.
                */
               e = (*com->c_func)(0);
               break;

       default:
               panic("Unknown argtype");
       }

       /*
        * Exit the current source file on
        * error.
        */

       if (e && sourcing)
               unstack();
       if (com->c_func == edstop)
               return(1);
       if (value("autoprint") != NOSTR && com->c_argtype & P)
               if ((dot->m_flag & MDELETED) == 0)
                       print(dot);
       if (!sourcing)
               sawcom = 1;
       return(0);
}

/*
* Find the correct command in the command table corresponding
* to the passed command "word"
*/

struct cmd *
lex(word)
       char word[];
{
       register struct cmd *cp;
       extern struct cmd cmdtab[];

       for (cp = &cmdtab[0]; cp->c_name != NOSTR; cp++)
               if (isprefix(word, cp->c_name))
                       return(cp);
       return(NONE);
}

/*
* Determine if as1 is a valid prefix of as2.
* Return true if yep.
*/

isprefix(as1, as2)
       char *as1, *as2;
{
       register char *s1, *s2;

       s1 = as1;
       s2 = as2;
       while (*s1++ == *s2)
               if (*s2++ == '\0')
                       return(1);
       return(*--s1 == '\0');
}

/*
* The following gets called on receipt of a rubout.  This is
* to abort printout of a command, mainly.
* Dispatching here when command() is inactive crashes rcv.
* Close all open files except 0, 1, 2, and the temporary.
* The special call to getuserid() is needed so it won't get
* annoyed about losing its open file.
* Also, unstack all source files.
*/

stop()
{
       register FILE *fp;

       noreset = 0;
       signal(SIGINT, SIG_IGN);
       sawcom++;
       while (sourcing)
               unstack();
       getuserid((char *) -1);
       for (fp = &_iob[0]; fp < &_iob[_NFILE]; fp++) {
               if (fp == stdin || fp == stdout)
                       continue;
               if (fp == itf || fp == otf)
                       continue;
               if (fp == stderr)
                       continue;
               fclose(fp);
       }
       if (image >= 0) {
               close(image);
               image = -1;
       }
       clrbuf(stdout);
       printf("Interrupt\n");
       signal(SIGINT, stop);
       reset(0);
}

/*
* Announce the presence of the current Mail version,
* give the message count, and print a header listing.
*/

char    *greeting       = "Mail version 2.0 %s.  Type ? for help.\n";

announce()
{
       int vec[2];
       extern char *version;
       register struct message *mp;

       if (value("hold") != NOSTR)
               for (mp = &message[0]; mp < &message[msgCount]; mp++)
                       mp->m_flag |= MPRESERVE;
       vec[0] = 1;
       vec[1] = 0;
       if (value("quiet") == NOSTR)
               printf(greeting, version);
       if (msgCount == 1)
               printf("1 message:\n");
       else
               printf("%d messages:\n", msgCount);
       headers(vec);
}

strace() {}

/*
* Print the current version number.
*/

pversion(e)
{
       printf(greeting, version);
       return(0);
}