/*      $NetBSD: collect.c,v 1.49 2017/11/09 20:27:50 christos Exp $    */

/*
 * 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. 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.
 */

#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)collect.c   8.2 (Berkeley) 4/19/94";
#else
__RCSID("$NetBSD: collect.c,v 1.49 2017/11/09 20:27:50 christos Exp $");
#endif
#endif /* not lint */

/*
 * Mail -- a mail program
 *
 * Collect input from standard input, handling
 * ~ escapes.
 */

#include <assert.h>
#include <util.h>

#include "rcv.h"
#include "extern.h"
#include "format.h"
#ifdef MIME_SUPPORT
#include "mime.h"
#endif
#include "sig.h"
#include "thread.h"


/*
 * Read a message from standard input and return a read file to it
 * or NULL on error.
 */

/*
 * The following hokiness with global variables is so that on
 * receipt of an interrupt signal, the partial message can be salted
 * away on dead.letter.
 */
static  FILE    *collf;                 /* File for saving away */
static  int     hadintr;                /* Have seen one SIGINT so far */

static  jmp_buf abort_jmpbuf;           /* To end collection with error */
static  jmp_buf reset_jmpbuf;           /* To get back to work */
static  int     reset_on_stop;          /* To do job control longjmp. */

/*
 * Write a file, ex-like if f set.
 */
static int
exwrite(const char name[], FILE *fp, int f)
{
        FILE *of;
        int c;
        long cc;
        int lc;
        struct stat junk;

        if (f) {
                (void)printf("\"%s\" ", name);
                (void)fflush(stdout);
        }
        if (stat(name, &junk) >= 0 && S_ISREG(junk.st_mode)) {
                if (!f)
                        (void)fprintf(stderr, "%s: ", name);
                (void)fprintf(stderr, "File exists\n");
                return -1;
        }
        if ((of = Fopen(name, "we")) == NULL) {
                warn("%s", name);
                return -1;
        }
        lc = 0;
        cc = 0;
        while ((c = getc(fp)) != EOF) {
                cc++;
                if (c == '\n')
                        lc++;
                (void)putc(c, of);
                if (ferror(of)) {
                        warn("%s", name);
                        (void)Fclose(of);
                        return -1;
                }
        }
        (void)Fclose(of);
        (void)printf("%d/%ld\n", lc, cc);
        (void)fflush(stdout);
        return 0;
}

/*
 * Edit the message being collected on fp.
 * On return, make the edit file the new temp file.
 */
static void
mesedit(FILE *fp, int c)
{
        struct sigaction osa;
        sigset_t oset;
        FILE *nf;

        sig_check();
        (void)sig_ignore(SIGINT, &osa, &oset);
        nf = run_editor(fp, (off_t)-1, c, 0);
        if (nf != NULL) {
                (void)fseek(nf, 0L, 2);
                collf = nf;
                (void)Fclose(fp);
        }
        (void)sig_restore(SIGINT, &osa, &oset);
        sig_check();
}

/*
 * Pipe the message through the command.
 * Old message is on stdin of command;
 * New message collected from stdout.
 * Sh -c must return 0 to accept the new message.
 */
static void
mespipe(FILE *fp, char cmd[])
{
        FILE *nf;
        struct sigaction osa;
        sigset_t oset;
        const char *shellcmd;
        int fd;
        char tempname[PATHSIZE];

        sig_check();
        (void)sig_ignore(SIGINT, &osa, &oset);

        (void)snprintf(tempname, sizeof(tempname),
            "%s/mail.ReXXXXXXXXXX", tmpdir);
        if ((fd = mkstemp(tempname)) == -1 ||
            (nf = Fdopen(fd, "wef+")) == NULL) {
                if (fd != -1)
                        (void)close(fd);
                warn("%s", tempname);
                goto out;
        }
        (void)unlink(tempname);
        /*
         * stdin = current message.
         * stdout = new message.
         */
        if ((shellcmd = value(ENAME_SHELL)) == NULL)
                shellcmd = _PATH_CSHELL;
        if (run_command(shellcmd,
            NULL, fileno(fp), fileno(nf), "-c", cmd, NULL) < 0) {
                (void)Fclose(nf);
                goto out;
        }
        if (fsize(nf) == 0) {
                (void)fprintf(stderr, "No bytes from \"%s\" !?\n", cmd);
                (void)Fclose(nf);
                goto out;
        }
        /*
         * Take new files.
         */
        (void)fseek(nf, 0L, 2);
        collf = nf;
        (void)Fclose(fp);
 out:
        (void)sig_restore(SIGINT, &osa, &oset);
        sig_check();
}

/*
 * Interpolate the named messages into the current
 * message, preceding each line with a tab.
 * Return a count of the number of characters now in
 * the message, or -1 if an error is encountered writing
 * the message temporary.  The flag argument is 'm' if we
 * should shift over and 'f' if not.
 */
static int
interpolate(char ms[], FILE *fp, char *fn, int f)
{
        int *msgvec;
        struct ignoretab *ig;
        const char *tabst;
#ifdef MIME_SUPPORT
        struct mime_info *mip;
        int retval;
#endif
        msgvec = salloc((get_msgCount() + 1) * sizeof(*msgvec));
        if (msgvec == NULL)
                return 0;
        if (getmsglist(ms, msgvec, 0) < 0)
                return 0;
        if (*msgvec == 0) {
                *msgvec = first(0, MMNORM);
                if (*msgvec == 0) {
                        (void)printf("No appropriate messages\n");
                        return 0;
                }
                msgvec[1] = 0;
        }
        if (f == 'f' || f == 'F')
                tabst = NULL;
        else if ((tabst = value(ENAME_INDENTPREFIX)) == NULL)
                tabst = "\t";
        ig = isupper(f) ? NULL : ignore;
        (void)printf("Interpolating:");
        for (/*EMPTY*/; *msgvec != 0; msgvec++) {
                struct message *mp;
                char *fmtstr;

                mp = get_message(*msgvec);
                touch(mp);
                (void)printf(" %d", *msgvec);
                (void)fflush(stdout);   /* flush stdout and the above */

                if (tabst && (fmtstr = value(ENAME_INDENT_PREAMBLE)) != NULL)
                        fmsgprintf(collf, fmtstr, mp);
#ifdef MIME_SUPPORT
                mip = NULL;
                if (value(ENAME_MIME_DECODE_MSG)) {
                        if ((tabst == NULL && value(ENAME_MIME_DECODE_INSERT)) ||
                            (tabst != NULL && value(ENAME_MIME_DECODE_QUOTE)))
                                mip = mime_decode_open(mp);
                }
                retval = mime_sendmessage(mp, fp, ig, tabst, mip);
                mime_decode_close(mip);
                if (retval < 0)
#else
                if (sendmessage(mp, fp, ig, tabst, NULL) < 0)
#endif
                {
                        warn("%s", fn);
                        return -1;
                }
                if (tabst && (fmtstr = value(ENAME_INDENT_POSTSCRIPT)) != NULL)
                        fmsgprintf(collf, fmtstr, mp);
        }
        (void)printf("\n");
        return 0;
}

/*
 * Append the contents of the file to the end of the deadletter file.
 */
PUBLIC void
savedeadletter(FILE *fp)
{
        FILE *dbuf;
        mode_t m;
        int c;
        const char *cp;

        if (fsize(fp) == 0)
                return;
        cp = getdeadletter();
        m = umask(077);
        dbuf = Fopen(cp, "ae");
        (void)umask(m);
        if (dbuf == NULL)
                return;
        (void)printf("Saving message body to `%s'.\n", cp);
        while ((c = getc(fp)) != EOF)
                (void)putc(c, dbuf);
        (void)Fclose(dbuf);
        rewind(fp);
}

/*
 * On interrupt, come here to save the partial message in ~/dead.letter.
 * Then jump out of the collection loop.
 */
static void
coll_int(int signo)
{
        sig_t o = signal(SIGINT, SIG_IGN);

        /*
         * the control flow is subtle, because we can be called from ~q.
         */
        if (!hadintr) {
                if (value(ENAME_IGNORE) != NULL) {
                        (void)puts("@");
                        (void)fflush(stdout);
                        clearerr(stdin);
                        signal(SIGINT, o);
                        return;
                }
                hadintr = 1;
                signal(SIGINT, o);
                longjmp(reset_jmpbuf, signo);
        }
        if (collf) {
                rewind(collf);
                if (value(ENAME_NOSAVE) == NULL)
                        savedeadletter(collf);
        }
        signal(SIGINT, o);
        longjmp(abort_jmpbuf, signo);
}

/*ARGSUSED*/
__dead static void
coll_hup(int signo __unused)
{

        rewind(collf);
        savedeadletter(collf);
        /*
         * Let's pretend nobody else wants to clean up,
         * a true statement at this time.
         */
        exit(EXIT_FAILURE);
}

/*
 * Print (continue) when continued after ^Z.
 */
static void
coll_stop(int signo)
{

        if (reset_on_stop) {
                reset_on_stop = 0;
                hadintr = 0;
                longjmp(reset_jmpbuf, signo);
        }
}

PUBLIC FILE *
collect(struct header *hp, int printheaders)
{
        sig_t volatile old_sigint = sig_current(SIGINT);
        sig_t volatile old_sighup = sig_current(SIGHUP);
        sig_t volatile old_sigtstp = sig_current(SIGTSTP);
        sig_t volatile old_sigttin = sig_current(SIGTTIN);
        sig_t volatile old_sigttou = sig_current(SIGTTOU);
        FILE *fbuf;
        int lc, cc;
        int c, fd, t;
        char linebuf[LINESIZE];
        const char *cp;
        char tempname[PATHSIZE];
        char mailtempname[PATHSIZE];
        int eofcount;
        int longline;
        int lastlong, rc;       /* So we don't make 2 or more lines
                                   out of a long input line. */

        /* The following are declared volatile to avoid longjmp clobbering. */
        char volatile getsub;
        int volatile escape;

        (void)memset(mailtempname, 0, sizeof(mailtempname));
        collf = NULL;

        if (setjmp(abort_jmpbuf) || setjmp(reset_jmpbuf)) {
                (void)rm(mailtempname);
                goto err;
        }
        sig_check();

        sig_hold();
        old_sigint  = sig_signal(SIGINT,  coll_int);
        old_sighup  = sig_signal(SIGHUP,  coll_hup);
        old_sigtstp = sig_signal(SIGTSTP, coll_stop);
        old_sigttin = sig_signal(SIGTTIN, coll_stop);
        old_sigttou = sig_signal(SIGTTOU, coll_stop);
        sig_release();

        noreset++;
        (void)snprintf(mailtempname, sizeof(mailtempname),
            "%s/mail.RsXXXXXXXXXX", tmpdir);
        if ((fd = mkstemp(mailtempname)) == -1 ||
            (collf = Fdopen(fd, "wef+")) == NULL) {
                if (fd != -1)
                        (void)close(fd);
                warn("%s", mailtempname);
                goto err;
        }
        (void)rm(mailtempname);

        /*
         * If we are going to prompt for a subject,
         * refrain from printing a newline after
         * the headers (since some people mind).
         */
        t = GTO | GSUBJECT | GCC | GNL | GSMOPTS;
        getsub = 0;
        if (hp->h_subject == NULL && value(ENAME_INTERACTIVE) != NULL &&
            (value(ENAME_ASK) != NULL || value(ENAME_ASKSUB) != NULL)) {
                t &= ~GNL;
                getsub++;
        }
        if (printheaders) {
                (void)puthead(hp, stdout, t);
                (void)fflush(stdout);
        }
        if ((cp = value(ENAME_ESCAPE)) != NULL)
                escape = *cp;
        else
                escape = ESCAPE;
        hadintr = 0;
        if (setjmp(reset_jmpbuf) == 0) {
                if (getsub)
                        (void)grabh(hp, GSUBJECT);
        } else {
                /*
                 * Come here for printing the after-signal message.
                 * Duplicate messages won't be printed because
                 * the write is aborted if we get a SIGTTOU.
                 */
 cont:
                if (hadintr) {
                        (void)fflush(stdout);
                        (void)fprintf(stderr,
                        "\n(Interrupt -- one more to kill letter)\n");
                } else {
                        (void)printf("(continue)\n");
                        (void)fflush(stdout);
                }
        }
        eofcount = 0;   /* reset after possible longjmp */
        longline = 0;   /* reset after possible longjmp */
        for (;;) {
                reset_on_stop = 1;
                c = readline(stdin, linebuf, LINESIZE, reset_on_stop);
                reset_on_stop = 0;

                if (c < 0) {
                        char *p;

                        if (value(ENAME_INTERACTIVE) != NULL &&
                            (p = value(ENAME_IGNOREEOF)) != NULL &&
                            ++eofcount < (*p == 0 ? 25 : atoi(p))) {
                                (void)printf("Use \".\" to terminate letter\n");
                                continue;
                        }
                        break;
                }
                lastlong = longline;
                longline = c == LINESIZE - 1;
                eofcount = 0;
                hadintr = 0;
                if (linebuf[0] == '.' && linebuf[1] == '\0' &&
                    value(ENAME_INTERACTIVE) != NULL && !lastlong &&
                    (value(ENAME_DOT) != NULL || value(ENAME_IGNOREEOF) != NULL))
                        break;
                if (linebuf[0] != escape || value(ENAME_INTERACTIVE) == NULL ||
                    lastlong) {
                        if (putline(collf, linebuf, !longline) < 0)
                                goto err;
                        continue;
                }
                c = linebuf[1];
                switch (c) {
                default:
                        /*
                         * On double escape, just send the single one.
                         * Otherwise, it's an error.
                         */
                        if (c == escape) {
                                if (putline(collf, &linebuf[1], !longline) < 0)
                                        goto err;
                                else
                                        break;
                        }
                        (void)printf("Unknown tilde escape.\n");
                        break;
#ifdef MIME_SUPPORT
                case '@':
                        hp->h_attach = mime_attach_files(hp->h_attach, &linebuf[2]);
                        break;
#endif
                case 'C':
                        /*
                         * Dump core.
                         */
                        (void)core(NULL);
                        break;
                case '!':
                        /*
                         * Shell escape, send the balance of the
                         * line to sh -c.
                         */
                        (void)shell(&linebuf[2]);
                        break;
                case ':':
                case '_':
                        /*
                         * Escape to command mode, but be nice!
                         */
                        (void)execute(&linebuf[2], ec_composing);
                        goto cont;
                case '.':
                        /*
                         * Simulate end of file on input.
                         */
                        goto out;
                case 'q':
                        /*
                         * Force a quit of sending mail.
                         * Act like an interrupt happened.
                         */
                        hadintr++;
                        coll_int(SIGINT);
                        exit(1);
                        /*NOTREACHED*/

                case 'x':       /* exit, do not save in dead.letter */
                        goto err;

                case 'h':
                        /*
                         * Grab a bunch of headers.
                         */
                        (void)grabh(hp, GTO | GSUBJECT | GCC | GBCC | GSMOPTS);
                        goto cont;
                case 't':
                        /*
                         * Add to the To list.
                         */
                        hp->h_to = cat(hp->h_to, extract(&linebuf[2], GTO));
                        break;
                case 's':
                        /*
                         * Set the Subject list.
                         */
                        cp = skip_WSP(&linebuf[2]);
                        hp->h_subject = savestr(cp);
                        break;
                case 'c':
                        /*
                         * Add to the CC list.
                         */
                        hp->h_cc = cat(hp->h_cc, extract(&linebuf[2], GCC));
                        break;
                case 'b':
                        /*
                         * Add stuff to blind carbon copies list.
                         */
                        hp->h_bcc = cat(hp->h_bcc, extract(&linebuf[2], GBCC));
                        break;
                case 'i':
                case 'A':
                case 'a':
                        /*
                         * Insert named variable in message
                         */

                        switch(c) {
                                case 'i':
                                        cp = skip_WSP(&linebuf[2]);
                                        break;
                                case 'a':
                                        cp = "sign";
                                        break;
                                case 'A':
                                        cp = "Sign";
                                        break;
                                default:
                                        goto err;
                        }

                        if (*cp && (cp = value(cp)) != NULL) {
                                (void)printf("%s\n", cp);
                                if (putline(collf, cp, 1) < 0)
                                        goto err;
                        }

                        break;

                case 'd':
                        (void)strcpy(linebuf + 2, getdeadletter());
                        /* FALLTHROUGH */
                case 'r':
                case '<':
                        /*
                         * Invoke a file:
                         * Search for the file name,
                         * then open it and copy the contents to collf.
                         */
                        cp = skip_WSP(&linebuf[2]);
                        if (*cp == '\0') {
                                (void)printf("Interpolate what file?\n");
                                break;
                        }

                        cp = expand(cp);
                        if (cp == NULL)
                                break;

                        if (*cp == '!') {       /* insert stdout of command */
                                const char *shellcmd;
                                int nullfd;
                                int rc2;

                                if ((nullfd = open("/dev/null", O_RDONLY, 0)) == -1) {
                                        warn("/dev/null");
                                        break;
                                }

                                (void)snprintf(tempname, sizeof(tempname),
                                    "%s/mail.ReXXXXXXXXXX", tmpdir);
                                if ((fd = mkstemp(tempname)) == -1 ||
                                    (fbuf = Fdopen(fd, "wef+")) == NULL) {
                                        if (fd != -1)
                                                (void)close(fd);
                                        warn("%s", tempname);
                                        break;
                                }
                                (void)unlink(tempname);

                                if ((shellcmd = value(ENAME_SHELL)) == NULL)
                                        shellcmd = _PATH_CSHELL;

                                rc2 = run_command(shellcmd, NULL, nullfd, fileno(fbuf), "-c", cp + 1, NULL);

                                (void)close(nullfd);

                                if (rc2 < 0) {
                                        (void)Fclose(fbuf);
                                        break;
                                }

                                if (fsize(fbuf) == 0) {
                                        (void)fprintf(stderr, "No bytes from command \"%s\"\n", cp + 1);
                                        (void)Fclose(fbuf);
                                        break;
                                }

                                rewind(fbuf);
                        }
                        else if (isdir(cp)) {
                                (void)printf("%s: Directory\n", cp);
                                break;
                        }
                        else if ((fbuf = Fopen(cp, "re")) == NULL) {
                                warn("%s", cp);
                                break;
                        }
                        (void)printf("\"%s\" ", cp);
                        (void)fflush(stdout);
                        lc = 0;
                        cc = 0;
                        while ((rc = readline(fbuf, linebuf, LINESIZE, 0)) >= 0) {
                                if (rc != LINESIZE-1) lc++;
                                if ((t = putline(collf, linebuf,
                                                 rc != LINESIZE-1)) < 0) {
                                        (void)Fclose(fbuf);
                                        goto err;
                                }
                                cc += t;
                        }
                        (void)Fclose(fbuf);
                        (void)printf("%d/%d\n", lc, cc);
                        break;
                case 'w':
                        /*
                         * Write the message on a file.
                         */
                        cp = skip_WSP(&linebuf[2]);
                        if (*cp == '\0') {
                                (void)fprintf(stderr, "Write what file!?\n");
                                break;
                        }
                        if ((cp = expand(cp)) == NULL)
                                break;
                        rewind(collf);
                        (void)exwrite(cp, collf, 1);
                        break;
                case 'm':
                case 'M':
                case 'f':
                case 'F':
                        /*
                         * Interpolate the named messages, if we
                         * are in receiving mail mode.  Does the
                         * standard list processing garbage.
                         * If ~f is given, we don't shift over.
                         */
                        if (interpolate(linebuf + 2, collf, mailtempname, c) < 0)
                                goto err;
                        goto cont;
                case '?':
                        cathelp(_PATH_TILDE);
                        break;
                case 'p':
                        /*
                         * Print out the current state of the
                         * message without altering anything.
                         */
                        rewind(collf);
                        (void)printf("-------\nMessage contains:\n");
                        (void)puthead(hp, stdout,
                            GTO | GSUBJECT | GCC | GBCC | GSMOPTS | GNL);
                        while ((t = getc(collf)) != EOF)
                                (void)putchar(t);
                        goto cont;
                case '|':
                        /*
                         * Pipe message through command.
                         * Collect output as new message.
                         */
                        rewind(collf);
                        mespipe(collf, &linebuf[2]);
                        goto cont;
                case 'v':
                case 'e':
                        /*
                         * Edit the current message.
                         * 'e' means to use EDITOR
                         * 'v' means to use VISUAL
                         */
                        rewind(collf);
                        mesedit(collf, c);
                        goto cont;
                }
        }
        goto out;
 err:
        if (collf != NULL) {
                (void)Fclose(collf);
                collf = NULL;
        }
 out:
        if (collf != NULL)
                rewind(collf);
        noreset--;

        sig_hold();
        (void)sig_signal(SIGINT,  old_sigint);
        (void)sig_signal(SIGHUP,  old_sighup);
        (void)sig_signal(SIGTSTP, old_sigtstp);
        (void)sig_signal(SIGTTIN, old_sigttin);
        (void)sig_signal(SIGTTOU, old_sigttou);
        sig_release();

        sig_check();
        return collf;
}