README: mention *crawl* branch

[s-mailx.git] / main.c

/*@ S-nail - a mail user agent derived from Berkeley Mail.
 *@ Startup -- interface with user.
 *
 * Copyright (c) 2000-2004 Gunnar Ritter, Freiburg i. Br., Germany.
 * Copyright (c) 2012 - 2013 Steffen "Daode" Nurpmeso <sdaoden@users.sf.net>.
 */
/*
 * 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.
 */

/*
 * Most strcpy/sprintf functions have been changed to strncpy/snprintf to
 * correct several buffer overruns (at least one ot them was exploitable).
 * Sat Jun 20 04:58:09 CEST 1998 Alvaro Martinez Echevarria <alvaro@lander.es>
 * ---
 * Note: We set egid to realgid ... and only if we need the egid we will
 *       switch back temporary.  Nevertheless, I do not like seg faults.
 *       Werner Fink, <werner@suse.de>
 */

#include "config.h"

#include <sys/ioctl.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <termios.h>
#include <unistd.h>
#ifdef HAVE_NL_LANGINFO
# include <langinfo.h>
#endif
#ifdef HAVE_SETLOCALE
# include <locale.h>
#endif

#define _MAIL_GLOBS_
#include "rcv.h"
#include "extern.h"

struct a_arg {
        struct a_arg    *aa_next;
        char            *aa_file;
};

/* Perform basic startup initialization */
static void     _startup(void);

/* Grow a char** */
static int      _grow_cpp(char const ***cpp, int size, int count);

/* Initialize *tempdir*, *myname*, *homedir* */
static void     _setup_vars(void);

/* We're in an interactive session - compute what the screen size for printing
 * headers etc. should be; notify tty upon resize if *is_sighdl* is not 0.
 * We use the following algorithm for the height:
 *      If baud rate < 1200, use  9
 *      If baud rate = 1200, use 14
 *      If baud rate > 1200, use 24 or ws_row
 * Width is either 80 or ws_col */
static void     _setscreensize(int is_sighdl);

/* Ok, we are reading mail.  Decide whether we are editing a mailbox or reading
 * the system mailbox, and open up the right stuff */
static int      _rcv_mode(char const *folder);

/* Interrupt printing of the headers */
static void     _hdrstop(int signo);

static void
_startup(void)
{
        char *cp;

        /* Absolutely the first thing we do is save our egid
         * and set it to the rgid, so that we can safely run
         * setgid.  We use the sgid (saved set-gid) to allow ourselves
         * to revert to the egid if we want (temporarily) to become
         * privileged */
        effectivegid = getegid();
        realgid = getgid();
        if (setgid(realgid) < 0) {
                perror("setgid");
                exit(1);
        }

        image = -1;

        if ((cp = strrchr(progname, '/')) != NULL)
                progname = ++cp;

        /* Set up a reasonable environment.
         * Figure out whether we are being run interactively,
         * start the SIGCHLD catcher, and so forth */
        safe_signal(SIGCHLD, sigchild);

        if (isatty(0))
                options |= OPT_TTYIN | OPT_INTERACTIVE;
        if (isatty(1))
                options |= OPT_TTYOUT;
        if (IS_TTY_SESSION())
                safe_signal(SIGPIPE, dflpipe = SIG_IGN);
        assign("header", "");
        assign("save", "");

#ifdef HAVE_SETLOCALE
        setlocale(LC_ALL, "");
        mb_cur_max = MB_CUR_MAX;
# if defined HAVE_NL_LANGINFO && defined CODESET
        if (value("ttycharset") == NULL && (cp = nl_langinfo(CODESET)) != NULL)
                assign("ttycharset", cp);
# endif

# if defined HAVE_MBTOWC && defined HAVE_WCTYPE_H
        if (mb_cur_max > 1) {
                wchar_t wc;
                if (mbtowc(&wc, "\303\266", 2) == 2 && wc == 0xF6 &&
                                mbtowc(&wc, "\342\202\254", 3) == 3 &&
                                wc == 0x20AC)
                        utf8 = 1;
                /* Reset state - it may have been messed up; luckily this also
                 * gives us an indication wether the encoding has locking shift
                 * state sequences */
                /* TODO temporary - use option bits! */
                enc_has_state = mbtowc(&wc, NULL, mb_cur_max);
        }
# endif
#else
        mb_cur_max = 1;
#endif

#ifdef HAVE_CATGETS
# ifdef NL_CAT_LOCALE
        catd = catopen(CATNAME, NL_CAT_LOCALE);
# else
        catd = catopen(CATNAME, 0);
# endif
#endif

#ifdef HAVE_ICONV
        iconvd = (iconv_t)-1;
#endif
}

static int
_grow_cpp(char const ***cpp, int size, int count)
{
        /* Before spreserve(): use our string pool instead of LibC heap;
         * Increment *size* by at least 5! */
        char const **newcpp = salloc(sizeof(char*) * (size += 8));

        if (count > 0)
                memcpy(newcpp, *cpp, count * sizeof(char*));
        *cpp = newcpp;
        return size;
}

static void
_setup_vars(void)
{
        /* Before spreserve(): use our string pool instead of LibC heap */
        char const *cp;

        tempdir = ((cp = getenv("TMPDIR")) != NULL) ? savestr(cp) : "/tmp";

        myname = savestr(username());

        if ((cp = getenv("HOME")) == NULL)
                cp = ".";
        homedir = savestr(cp);
}

static void
_setscreensize(int is_sighdl)
{
        struct termios tbuf;
#ifdef TIOCGWINSZ
        struct winsize ws;
#elif defined TIOCGSIZE
        struct ttysize ts;
#endif

        scrnheight = realscreenheight = scrnwidth = 0;

        /* (Also) POSIX: LINES and COLUMNS always override.  Adjust this
         * a little bit to be able to honour resizes during our lifetime and
         * only honour it upon first run; abuse *is_sighdl* as an indicator */
        if (is_sighdl == 0) {
                char *cp;
                long i;

                if ((cp = getenv("LINES")) != NULL &&
                                (i = strtol(cp, NULL, 10)) > 0)
                        scrnheight = realscreenheight = (int)i;
                if ((cp = getenv("COLUMNS")) != NULL &&
                                (i = strtol(cp, NULL, 10)) > 0)
                        scrnwidth = (int)i;

                if (scrnwidth != 0 && scrnheight != 0)
                        goto jleave;
        }

#ifdef TIOCGWINSZ
        if (ioctl(1, TIOCGWINSZ, &ws) < 0)
                ws.ws_col = ws.ws_row = 0;
#elif defined TIOCGSIZE
        if (ioctl(1, TIOCGSIZE, &ws) < 0)
                ts.ts_lines = ts.ts_cols = 0;
#endif

        if (scrnheight == 0) {
                speed_t ospeed = (tcgetattr(1, &tbuf) < 0) ? B9600 :
                                cfgetospeed(&tbuf);

                if (ospeed < B1200)
                        scrnheight = 9;
                else if (ospeed == B1200)
                        scrnheight = 14;
#ifdef TIOCGWINSZ
                else if (ws.ws_row != 0)
                        scrnheight = ws.ws_row;
#elif defined TIOCGSIZE
                else if (ts.ts_lines != 0)
                        scrnheight = ts.ts_lines;
#endif
                else
                        scrnheight = 24;

#if defined TIOCGWINSZ || defined TIOCGSIZE
                if (0 ==
# ifdef TIOCGWINSZ
                                (realscreenheight = ws.ws_row)
# else
                                (realscreenheight = ts.ts_lines)
# endif
                )
                        realscreenheight = 24;
#endif
        }

        if (scrnwidth == 0 && 0 ==
#ifdef TIOCGWINSZ
                        (scrnwidth = ws.ws_col)
#elif defined TIOCGSIZE
                        (scrnwidth = ts.ts_cols)
#endif
        )
                scrnwidth = 80;

jleave:
#ifdef SIGWINCH
        if (is_sighdl && (options & OPT_INTERACTIVE))
                tty_signal(SIGWINCH);
#endif
}

static sigjmp_buf       __hdrjmp; /* XXX */

static int
_rcv_mode(char const *folder)
{
        char *cp;
        int i;
        sighandler_type prevint;

        if (folder == NULL)
                folder = "%";
        else if (*folder == '@') {
                /* This must be treated specially to make invocation like
                 * -A imap -f @mailbox work */
                if ((cp = value("folder")) != NULL &&
                                which_protocol(cp) == PROTO_IMAP)
                        (void)n_strlcpy(mailname, cp, MAXPATHLEN);
        }

        i = setfile(folder, 0);
        if (i < 0)
                exit(1);                /* error already reported */
        if (options & OPT_EXISTONLY)
                exit(i);

        if (options & OPT_HEADERSONLY) {
#ifdef USE_IMAP
                if (mb.mb_type == MB_IMAP)
                        imap_getheaders(1, msgCount);
#endif
                time_current_update(&time_current, FAL0);
                for (i = 1; i <= msgCount; i++)
                        printhead(i, stdout, 0);
                exit(exit_status);
        }

        callhook(mailname, 0);
        if (i > 0 && value("emptystart") == NULL)
                exit(1);

        if (sigsetjmp(__hdrjmp, 1) == 0) {
                if ((prevint = safe_signal(SIGINT, SIG_IGN)) != SIG_IGN)
                        safe_signal(SIGINT, _hdrstop);
                if ((options & OPT_N_FLAG) == 0) {
                        if (! value("quiet"))
                                printf(tr(140,
                                        "%s version %s.  Type ? for help.\n"),
                                        value("bsdcompat") ? "Mail" : uagent,
                                        version);
                        announce(1);
                        fflush(stdout);
                }
                safe_signal(SIGINT, prevint);
        }

        /* Enter the command loop */
        if (options & OPT_INTERACTIVE)
                tty_init();
        commands();
        if (options & OPT_INTERACTIVE)
                tty_destroy();

        if (mb.mb_type == MB_FILE || mb.mb_type == MB_MAILDIR) {
                safe_signal(SIGHUP, SIG_IGN);
                safe_signal(SIGINT, SIG_IGN);
                safe_signal(SIGQUIT, SIG_IGN);
        }
        n_strlcpy(mboxname, expand("&"), sizeof(mboxname));
        quit();
        return exit_status;
}

static void
_hdrstop(int signo)
{
        (void)signo;

        fflush(stdout);
        fprintf(stderr, tr(141, "\nInterrupt\n"));
        siglongjmp(__hdrjmp, 1);
}

char const *const       weekday_names[7 + 1] = {
        "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", NULL
};
char const *const       month_names[12 + 1] = {
        "Jan", "Feb", "Mar", "Apr", "May", "Jun",
        "Jul", "Aug", "Sep", "Oct", "Nov", "Dec", NULL
};

sighandler_type         dflpipe = SIG_DFL;

int 
main(int argc, char *argv[])
{
        static char const optstr[] = "A:a:Bb:c:DdEeFfHiNnO:q:Rr:S:s:tu:Vv~#",
                usagestr[] =
                "Synopsis:\n"
                "  %s [-BDdEFintv~] [-A acc] [-a attachment] "
                        "[-b bcc-addr] [-c cc-addr]\n"
                "\t  [-O mtaopt [-O mtaopt-arg]] [-q file] [-r from-addr] "
                        "[-S var[=value]]\n"
                "\t  [-s subject] to-addr...\n"
                "  %s [-BDdEeHiNnRv~#] [-A acct] "
                        "[-S var[=value]] -f [file]\n"
                "  %s [-BDdEeiNnRv~#] [-A acc] [-S var[=value]] [-u user]\n";

        struct a_arg *a_head = NULL, *a_curr = /* silence CC */ NULL;
        struct name *to = NULL, *cc = NULL, *bcc = NULL;
        struct attachment *attach = NULL;
        char *cp = NULL, *subject = NULL, *qf = NULL, *Aflag = NULL;
        char const *okey, **oargs = NULL, *folder = NULL;
        int oargs_size = 0, oargs_count = 0, smopts_size = 0, i;

        /*
         * Start our lengthy setup
         */

        starting =
        unset_allow_undefined = TRU1;

        progname = argv[0];
        _startup();

        /* Command line parsing */
        while ((i = getopt(argc, argv, optstr)) >= 0) {
                switch (i) {
                case 'A':
                        /* Execute an account command later on */
                        Aflag = optarg;
                        break;
                case 'a':
                        {       struct a_arg *nap = ac_alloc(
                                                sizeof(struct a_arg));
                                if (a_head == NULL)
                                        a_head = nap;
                                else
                                        a_curr->aa_next = nap;
                                nap->aa_next = NULL;
                                nap->aa_file = optarg;
                                a_curr = nap;
                        }
                        options |= OPT_SENDMODE;
                        break;
                case 'B':
                        /* Make 0/1 line buffered */
                        setvbuf(stdin, NULL, _IOLBF, 0);
                        setvbuf(stdout, NULL, _IOLBF, 0);
                        break;
                case 'b':
                        /* Get Blind Carbon Copy Recipient list */
                        bcc = cat(bcc, checkaddrs(lextract(optarg,GBCC|GFULL)));
                        options |= OPT_SENDMODE;
                        break;
                case 'c':
                        /* Get Carbon Copy Recipient list */
                        cc = cat(cc, checkaddrs(lextract(optarg, GCC|GFULL)));
                        options |= OPT_SENDMODE;
                        break;
                case 'D':
#ifdef USE_IMAP
                        okey = "disconnected";
                        goto joarg;
#else
                        break;
#endif
                case 'd':
                        okey = "debug";
#ifdef WANT_ASSERTS
                        assign(okey, "");
#endif
                        goto joarg;
                case 'E':
                        okey = "skipemptybody";
                        goto joarg;
                case 'e':
                        options |= OPT_EXISTONLY;
                        break;
                case 'F':
                        options |= OPT_F_FLAG | OPT_SENDMODE;
                        break;
                case 'f':
                        /* User is specifying file to "edit" with Mail,
                         * as opposed to reading system mailbox.
                         * If no argument is given, we read his mbox file.
                         * Check for remaining arguments later */
                        folder = "&";
                        break;
                case 'H':
                        options |= OPT_HEADERSONLY;
                        break;
                case 'i':
                        /* Ignore interrupts */
                        okey = "ignore";
                        goto joarg;
                case 'N':
                        /* Avoid initial header printing */
                        okey = "noheader";
                        goto joarg;
                case 'n':
                        /* Don't source "unspecified system start-up file" */
                        options |= OPT_NOSRC;
                        break;
                case 'O':
                        /* Additional options to pass-through to MTA */
                        if (smopts_count == (size_t)smopts_size)
                                smopts_size = _grow_cpp(&smopts, smopts_size,
                                                (int)smopts_count);
                        smopts[smopts_count++] = skin(optarg);
                        break;
                case 'q':
                        /* Quote file TODO drop? -Q with real quote?? what ? */
                        if (*optarg != '-')
                                qf = optarg;
                        options |= OPT_SENDMODE;
                        break;
                case 'R':
                        /* Open folders read-only */
                        options |= OPT_R_FLAG;
                        break;
                case 'r':
                        /* Set From address. */
                        options |= OPT_r_FLAG;
                        if ((option_r_arg = optarg)[0] != '\0') {
                                struct name *fa = nalloc(optarg, GFULL);

                                if (is_addr_invalid(fa, 1) ||
                                                is_fileorpipe_addr(fa)) {
                                        fprintf(stderr, tr(271,
                                                "Invalid address argument "
                                                "with -r\n"));
                                        goto usage;
                                }
                                option_r_arg = fa->n_name;
                                /* TODO -r options is set in smopts, but may
                                 * TODO be overwritten by setting from= in
                                 * TODO an interactive session!
                                 * TODO Maybe disable setting of from?
                                 * TODO Warn user?  Update manual!! */
                                okey = savecat("from=", fa->n_fullname);
                                goto joarg;
                                /* ..and fa goes even though it is ready :/ */
                        }
                        break;
                case 'S':
                        /* Set variable.  We need to do this twice, since the
                         * user surely wants the setting to take effect
                         * immediately, but also doesn't want it to be
                         * overwritten from within resource files */
                        {       char *a[2];
                                okey = a[0] = optarg;
                                a[1] = NULL;
                                set(a);
                        }
joarg:
                        if (oargs_count == oargs_size)
                                oargs_size = _grow_cpp(&oargs, oargs_size,
                                                oargs_count);
                        oargs[oargs_count++] = okey;
                        break;
                case 's':
                        /* Subject: */
                        subject = optarg;
                        options |= OPT_SENDMODE;
                        break;
                case 't':
                        /* Read defined set of headers from mail to be send */
                        options |= OPT_SENDMODE | OPT_t_FLAG;
                        break;
                case 'u':
                        /* Set user name to pretend to be  */
                        myname = option_u_arg = optarg;
                        break;
                case 'V':
                        puts(version);
                        exit(0);
                        /* NOTREACHED */
                case 'v':
                        /* Be verbose */
                        okey = "verbose";
#ifdef WANT_ASSERTS
                        assign(okey, "");
#endif
                        goto joarg;
                case '~':
                        /* Enable tilde escapes even in non-interactive mode */
                        options |= OPT_TILDE_FLAG;
                        break;
                case '#':
                        /* Work in batch mode, even if non-interactive */
                        if (oargs_count + 3 >= oargs_size)
                                oargs_size = _grow_cpp(&oargs, oargs_size,
                                                oargs_count);
                        oargs[oargs_count++] = "dot";
                        oargs[oargs_count++] = "emptystart";
                        oargs[oargs_count++] = "noheader";
                        oargs[oargs_count++] = "sendwait";
                        options |= OPT_TILDE_FLAG | OPT_BATCH_FLAG;
                        break;
                case '?':
usage:                  fprintf(stderr, tr(135, usagestr),
                                progname, progname, progname);
                        exit(2);
                }
        }

        if (folder != NULL) {
                if (optind < argc) {
                        if (optind + 1 < argc) {
                                fprintf(stderr, tr(205,
                                        "More than one file given with -f\n"));
                                goto usage;
                        }
                        folder = argv[optind];
                }
        } else {
                for (i = optind; argv[i]; i++)
                        to = cat(to, checkaddrs(lextract(argv[i], GTO|GFULL)));
                if (to != NULL)
                        options |= OPT_SENDMODE;
        }

        /* Check for inconsistent arguments */
        if (folder != NULL && to != NULL) {
                fprintf(stderr, tr(137,
                        "Cannot give -f and people to send to.\n"));
                goto usage;
        }
        if ((options & (OPT_SENDMODE|OPT_t_FLAG)) == OPT_SENDMODE &&
                        to == NULL) {
                fprintf(stderr, tr(138,
                        "Send options without primary recipient specified.\n"));
                goto usage;
        }
        if ((options & OPT_R_FLAG) && to != NULL) {
                fprintf(stderr, "The -R option is meaningless in send mode.\n");
                goto usage;
        }

        /*
         * Likely to go, perform more setup
         */

        _setup_vars();

        if (options & OPT_INTERACTIVE) {
                _setscreensize(0);
#ifdef SIGWINCH
# ifndef TTY_WANTS_SIGWINCH
                if (safe_signal(SIGWINCH, SIG_IGN) != SIG_IGN)
# endif
                        safe_signal(SIGWINCH, _setscreensize);
#endif
        } else
                scrnheight = realscreenheight = 24, scrnwidth = 80;

        /* Snapshot our string pools.  Memory is auto-reclaimed from now on */
        spreserve();

        if ((options & OPT_NOSRC) == 0)
                load(SYSCONFRC);
        /* *expand() returns a savestr(), but load only uses the file name
         * for fopen(), so it's safe to do this */
        if ((cp = getenv("MAILRC")) != NULL)
                load(file_expand(cp));
        else if ((cp = getenv("NAILRC")) != NULL)
                load(file_expand(cp));
        else
                load(file_expand("~/.mailrc"));
        if (getenv("NAIL_EXTRA_RC") == NULL &&
                        (cp = value("NAIL_EXTRA_RC")) != NULL)
                load(file_expand(cp));

        /* Now we can set the account */
        if (Aflag != NULL) {
                char *a[2];
                a[0] = Aflag;
                a[1] = NULL;
                account(a);
        }

        /* Ensure the -S and other command line options take precedence over
         * anything that may have been placed in resource files */
        for (i = 0; i < oargs_count; ++i) {
                char const *a[2];
                a[0] = oargs[i];
                a[1] = NULL;
                set(a);
        }

        /*
         * We're finally completely setup and ready to go
         */

        starting =
        unset_allow_undefined = FAL0;

        if (options & OPT_DEBUG)
                fprintf(stderr, tr(199, "user = %s, homedir = %s\n"),
                        myname, homedir);

        if (! (options & OPT_SENDMODE))
                return _rcv_mode(folder);

        /* Now that full mailx(1)-style file expansion is possible handle the
         * attachments which we had delayed due to this.
         * This may use savestr(), but since we won't enter the command loop we
         * don't need to care about that */
        while (a_head != NULL) {
                attach = add_attachment(attach, a_head->aa_file, NULL);
                if (attach != NULL) {
                        a_curr = a_head;
                        a_head = a_head->aa_next;
                        ac_free(a_curr);
                } else {
                        perror(a_head->aa_file);
                        exit(1);
                }
        }

        /* xxx exit_status = EXIT_OK; */
        if (options & OPT_INTERACTIVE)
                tty_init();
        mail(to, cc, bcc, subject, attach, qf, ((options & OPT_F_FLAG) != 0));
        if (options & OPT_INTERACTIVE)
                tty_destroy();
        return exit_status;
}