BSD 4_4 release

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

/*
* Copyright (c) 1980, 1993
*      The Regents of the University of California.  All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
*    must display the following acknowledgement:
*      This product includes software developed by the University of
*      California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#ifndef lint
static char sccsid[] = "@(#)lex.c       8.1 (Berkeley) 6/6/93";
#endif /* not lint */

#include "rcv.h"
#include <errno.h>
#include <fcntl.h>
#include "extern.h"

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

char    *prompt = "& ";

/*
* Set up editing on the given file name.
* If the first character of name is %, we are considered to be
* editing the file, otherwise we are reading our mail which has
* signficance for mbox and so forth.
*/
int
setfile(name)
       char *name;
{
       FILE *ibuf;
       int i;
       struct stat stb;
       char isedit = *name != '%';
       char *who = name[1] ? name + 1 : myname;
       static int shudclob;
       extern char tempMesg[];
       extern int errno;

       if ((name = expand(name)) == NOSTR)
               return -1;

       if ((ibuf = Fopen(name, "r")) == NULL) {
               if (!isedit && errno == ENOENT)
                       goto nomail;
               perror(name);
               return(-1);
       }

       if (fstat(fileno(ibuf), &stb) < 0) {
               perror("fstat");
               Fclose(ibuf);
               return (-1);
       }

       switch (stb.st_mode & S_IFMT) {
       case S_IFDIR:
               Fclose(ibuf);
               errno = EISDIR;
               perror(name);
               return (-1);

       case S_IFREG:
               break;

       default:
               Fclose(ibuf);
               errno = EINVAL;
               perror(name);
               return (-1);
       }

       /*
        * Looks like all will be well.  We must now relinquish our
        * hold on the current set of stuff.  Must hold signals
        * while we are reading the new file, else we will ruin
        * the message[] data structure.
        */

       holdsigs();
       if (shudclob)
               quit();

       /*
        * Copy the messages into /tmp
        * and set pointers.
        */

       readonly = 0;
       if ((i = open(name, 1)) < 0)
               readonly++;
       else
               close(i);
       if (shudclob) {
               fclose(itf);
               fclose(otf);
       }
       shudclob = 1;
       edit = isedit;
       strcpy(prevfile, mailname);
       if (name != mailname)
               strcpy(mailname, name);
       mailsize = fsize(ibuf);
       if ((otf = fopen(tempMesg, "w")) == NULL) {
               perror(tempMesg);
               exit(1);
       }
       (void) fcntl(fileno(otf), F_SETFD, 1);
       if ((itf = fopen(tempMesg, "r")) == NULL) {
               perror(tempMesg);
               exit(1);
       }
       (void) fcntl(fileno(itf), F_SETFD, 1);
       rm(tempMesg);
       setptr(ibuf);
       setmsize(msgCount);
       Fclose(ibuf);
       relsesigs();
       sawcom = 0;
       if (!edit && msgCount == 0) {
nomail:
               fprintf(stderr, "No mail for %s\n", who);
               return -1;
       }
       return(0);
}

int     *msgvec;
int     reset_on_stop;                  /* do a reset() if stopped */

/*
* Interpret user commands one by one.  If standard input is not a tty,
* print no prompt.
*/
void
commands()
{
       int eofloop = 0;
       register int n;
       char linebuf[LINESIZE];
       void intr(), stop(), hangup();

       if (!sourcing) {
               if (signal(SIGINT, SIG_IGN) != SIG_IGN)
                       signal(SIGINT, intr);
               if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
                       signal(SIGHUP, hangup);
               signal(SIGTSTP, stop);
               signal(SIGTTOU, stop);
               signal(SIGTTIN, stop);
       }
       setexit();
       for (;;) {
               /*
                * Print the prompt, if needed.  Clear out
                * string space, and flush the output.
                */
               if (!sourcing && value("interactive") != NOSTR) {
                       reset_on_stop = 1;
                       printf(prompt);
               }
               fflush(stdout);
               sreset();
               /*
                * Read a line of commands from the current input
                * and handle end of file specially.
                */
               n = 0;
               for (;;) {
                       if (readline(input, &linebuf[n], LINESIZE - n) < 0) {
                               if (n == 0)
                                       n = -1;
                               break;
                       }
                       if ((n = strlen(linebuf)) == 0)
                               break;
                       n--;
                       if (linebuf[n] != '\\')
                               break;
                       linebuf[n++] = ' ';
               }
               reset_on_stop = 0;
               if (n < 0) {
                               /* eof */
                       if (loading)
                               break;
                       if (sourcing) {
                               unstack();
                               continue;
                       }
                       if (value("interactive") != NOSTR &&
                           value("ignoreeof") != NOSTR &&
                           ++eofloop < 25) {
                               printf("Use \"quit\" to quit.\n");
                               continue;
                       }
                       break;
               }
               eofloop = 0;
               if (execute(linebuf, 0))
                       break;
       }
}

/*
* Execute a single command.
* Command functions return 0 for success, 1 for error, and -1
* for abort.  A 1 or -1 aborts a load or source.  A -1 aborts
* the interactive command loop.
* Contxt is non-zero if called while composing mail.
*/
int
execute(linebuf, contxt)
       char linebuf[];
       int contxt;
{
       char word[LINESIZE];
       char *arglist[MAXARGC];
       struct cmd *com;
       register char *cp, *cp2;
       register int c;
       int muvec[2];
       int e = 1;

       /*
        * 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.
        */

       for (cp = linebuf; isspace(*cp); cp++)
               ;
       if (*cp == '!') {
               if (sourcing) {
                       printf("Can't \"!\" while sourcing\n");
                       goto out;
               }
               shell(cp+1);
               return(0);
       }
       cp2 = word;
       while (*cp && index(" \t0123456789$^.:/-+*'\"", *cp) == NOSTR)
               *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 && *word == '\0')
               return(0);
       com = lex(word);
       if (com == NONE) {
               printf("Unknown command: \"%s\"\n", word);
               goto out;
       }

       /*
        * See if we should execute the command -- if a conditional
        * we always execute it, otherwise, check the state of cond.
        */

       if ((com->c_argtype & F) == 0)
               if (cond == CRCV && !rcvmode || cond == CSEND && rcvmode)
                       return(0);

       /*
        * 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);
               goto out;
       }
       if (sourcing && com->c_argtype & I) {
               printf("May not execute \"%s\" while sourcing\n",
                   com->c_name);
               goto out;
       }
       if (readonly && com->c_argtype & W) {
               printf("May not execute \"%s\" -- message file is read only\n",
                  com->c_name);
               goto out;
       }
       if (contxt && com->c_argtype & R) {
               printf("Cannot recursively invoke \"%s\"\n", com->c_name);
               goto out;
       }
       switch (com->c_argtype & ~(F|P|I|M|T|W|R)) {
       case MSGLIST:
               /*
                * A message list defaulting to nearest forward
                * legal message.
                */
               if (msgvec == 0) {
                       printf("Illegal use of \"message list\"\n");
                       break;
               }
               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 (msgvec == 0) {
                       printf("Illegal use of \"message list\"\n");
                       break;
               }
               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 (isspace(*cp))
                       cp++;
               e = (*com->c_func)(cp);
               break;

       case RAWLIST:
               /*
                * A vector of strings, in shell style.
                */
               if ((c = getrawlist(cp, arglist,
                               sizeof arglist / sizeof *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");
       }

out:
       /*
        * Exit the current source file on
        * error.
        */
       if (e) {
               if (e < 0)
                       return 1;
               if (loading)
                       return 1;
               if (sourcing)
                       unstack();
               return 0;
       }
       if (value("autoprint") != NOSTR && com->c_argtype & P)
               if ((dot->m_flag & MDELETED) == 0) {
                       muvec[0] = dot - &message[0] + 1;
                       muvec[1] = 0;
                       type(muvec);
               }
       if (!sourcing && (com->c_argtype & T) == 0)
               sawcom = 1;
       return(0);
}

/*
* Set the size of the message vector used to construct argument
* lists to message list functions.
*/
void
setmsize(sz)
       int sz;
{

       if (msgvec != 0)
               free((char *) msgvec);
       msgvec = (int *) calloc((unsigned) (sz + 1), sizeof *msgvec);
}

/*
* 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.
*/
int
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 an interrupt.  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.
* Also, unstack all source files.
*/

int     inithdr;                        /* am printing startup headers */

/*ARGSUSED*/
void
intr(s)
       int s;
{

       noreset = 0;
       if (!inithdr)
               sawcom++;
       inithdr = 0;
       while (sourcing)
               unstack();

       close_all_files();

       if (image >= 0) {
               close(image);
               image = -1;
       }
       fprintf(stderr, "Interrupt\n");
       reset(0);
}

/*
* When we wake up after ^Z, reprint the prompt.
*/
void
stop(s)
       int s;
{
       sig_t old_action = signal(s, SIG_DFL);

       sigsetmask(sigblock(0) & ~sigmask(s));
       kill(0, s);
       sigblock(sigmask(s));
       signal(s, old_action);
       if (reset_on_stop) {
               reset_on_stop = 0;
               reset(0);
       }
}

/*
* Branch here on hangup signal and simulate "exit".
*/
/*ARGSUSED*/
void
hangup(s)
       int s;
{

       /* nothing to do? */
       exit(1);
}

/*
* Announce the presence of the current Mail version,
* give the message count, and print a header listing.
*/
void
announce()
{
       int vec[2], mdot;

       mdot = newfileinfo();
       vec[0] = mdot;
       vec[1] = 0;
       dot = &message[mdot - 1];
       if (msgCount > 0 && value("noheader") == NOSTR) {
               inithdr++;
               headers(vec);
               inithdr = 0;
       }
}

/*
* Announce information about the file we are editing.
* Return a likely place to set dot.
*/
int
newfileinfo()
{
       register struct message *mp;
       register int u, n, mdot, d, s;
       char fname[BUFSIZ], zname[BUFSIZ], *ename;

       for (mp = &message[0]; mp < &message[msgCount]; mp++)
               if (mp->m_flag & MNEW)
                       break;
       if (mp >= &message[msgCount])
               for (mp = &message[0]; mp < &message[msgCount]; mp++)
                       if ((mp->m_flag & MREAD) == 0)
                               break;
       if (mp < &message[msgCount])
               mdot = mp - &message[0] + 1;
       else
               mdot = 1;
       s = d = 0;
       for (mp = &message[0], n = 0, u = 0; mp < &message[msgCount]; mp++) {
               if (mp->m_flag & MNEW)
                       n++;
               if ((mp->m_flag & MREAD) == 0)
                       u++;
               if (mp->m_flag & MDELETED)
                       d++;
               if (mp->m_flag & MSAVED)
                       s++;
       }
       ename = mailname;
       if (getfold(fname) >= 0) {
               strcat(fname, "/");
               if (strncmp(fname, mailname, strlen(fname)) == 0) {
                       sprintf(zname, "+%s", mailname + strlen(fname));
                       ename = zname;
               }
       }
       printf("\"%s\": ", ename);
       if (msgCount == 1)
               printf("1 message");
       else
               printf("%d messages", msgCount);
       if (n > 0)
               printf(" %d new", n);
       if (u-n > 0)
               printf(" %d unread", u);
       if (d > 0)
               printf(" %d deleted", d);
       if (s > 0)
               printf(" %d saved", s);
       if (readonly)
               printf(" [Read only]");
       printf("\n");
       return(mdot);
}

/*
* Print the current version number.
*/

/*ARGSUSED*/
int
pversion(e)
       int e;
{
       extern char *version;

       printf("Version %s\n", version);
       return(0);
}

/*
* Load a file of user definitions.
*/
void
load(name)
       char *name;
{
       register FILE *in, *oldin;

       if ((in = Fopen(name, "r")) == NULL)
               return;
       oldin = input;
       input = in;
       loading = 1;
       sourcing = 1;
       commands();
       loading = 0;
       sourcing = 0;
       input = oldin;
       Fclose(in);
}