source: trunk/athena/bin/discuss/client/edit.c @ 12439

/*
 *
 *    Copyright (C) 1989 by the Massachusetts Institute of Technology
 *    Developed by the MIT Student Information Processing Board (SIPB).
 *    For copying information, see the file mit-copyright.h in this release.
 *
 */
/*
 *      $Id: edit.c,v 1.16 1999-02-02 20:39:46 kcr Exp $
 *
 *      Utility routines.
 *
 *
 */

#ifndef lint
static char rcsid_discuss_utils_c[] =
    "$Id: edit.c,v 1.16 1999-02-02 20:39:46 kcr Exp $";
#endif /* lint */

#include <stdio.h>
#include <sys/file.h>
#include <string.h>
#include <signal.h>
#include <ss/ss.h>
#include <discuss/discuss.h>
#include "globals.h"
#include <sys/types.h>
#if HAVE_SYS_WAIT_H
#include <sys/wait.h>
#endif
#ifndef WEXITSTATUS
#define WEXITSTATUS(stat_val) ((unsigned)(stat_val) >> 8)
#endif
#include <sys/stat.h>
#include <sys/errno.h>

bool    use_editor = TRUE;
char    *editor_path = NULL;

extern char *getenv();

/*
 * int edit(fn, editor)
 *
 * fn: pathname of file to edit
 *
 * editor:
 *      name of editor command to run; if NULL, use the default
 * (specified on the command line or $EDITOR); if "", use a simple
 * type-in prompter.
 * 
 * return value: error_code if error occurs, or child exits with nonzero
 *      status, 0 otherwise
 *
 * call up an editor (from environment variable EDITOR or default
 *      value DEFAULT_EDITOR) on the specified file.
 */

int
edit(fn, edit_path)
        char *fn;
        char *edit_path;
{
        char *editor_path_e, *editor_path_2 = NULL;
        char *editor_path_v;
        int pid;
        int (*handler)();
        int wbuf;

        struct stat buf;
        char buffer[BUFSIZ];
        FILE *the_file = NULL;
#if HAVE_SIGACTION
        struct sigaction act, oact;
        sigemptyset(&act.sa_mask);
        act.sa_flags = 0;
#endif

        editor_path_e = getenv("EDITOR");
        if (!editor_path_e) editor_path_e = "/bin/ed";
        editor_path_v = getenv("VISUAL");
        if (!editor_path_v) editor_path_v = "/usr/ucb/vi";

        if (use_editor && editor_path && !edit_path)
            editor_path_2 = editor_path; 
        else if (edit_path && (*edit_path != '\0'))
            editor_path_2 = edit_path;
        else {
                the_file = fopen(fn, "w");
                if (!the_file) { 
                        perror(fn);
                        printf("Error opening file: %d\n",errno);
                        return(errno);
                }

                ftruncate(fileno(the_file), 0);
                fchmod(fileno(the_file), 0700);
                printf("Enter transaction; end with ^D or '.' on a line by itself.\n");
                for (;;) {
                        if ((gets(buffer) == NULL) || interrupt || !strcmp(buffer, ".")) break;
                        else if (!strcmp(buffer,"\\f")) {
                                editor_path_2 = editor_path_e;
                                break;
                        } else if (!strcmp(buffer,"~e")) {
                                editor_path_2 = editor_path_e;
                                break;
                        } else if (!strcmp(buffer,"~v")) {
                                editor_path_2 = editor_path_v;
                                break;
                        } else {
                                fputs(buffer,the_file);
                                fputc('\n',the_file);
                        }
                }
        }

        if (editor_path_2) {
                if (the_file) {
                        clearerr(stdin);
                        fclose(the_file);
                }
                switch ((pid = fork())) {
                case -1:
                        perror("couldn't fork");
                        printf("Couldn't fork, error %d\n",errno);
                        return(errno);
                case 0:
                        (void) execlp(editor_path_2, editor_path_2, fn, 0);
                        (void) perror(editor_path_2);
                        exit(1);
                default:
                        break;
                }
#if HAVE_SIGACTION
                act.sa_handler= (void (*)()) SIG_IGN;
                (void) sigaction(SIGINT, &act, &oact);
#else
                handler = signal(SIGINT, SIG_IGN);
#endif
                while (wait(&wbuf) != pid)
                        ;
#if HAVE_SIGACTION
              (void) sigaction(SIGINT, &oact, NULL);
#else
                (void) signal(SIGINT, handler);
#endif
                if (WIFSIGNALED(wbuf))
                        return(ET_CHILD_DIED);
                if (WEXITSTATUS(wbuf))
                        return(ET_CHILD_ERR);
        } else {
                clearerr(stdin);
                fclose(the_file);
        }

        if (stat (fn, &buf) != 0 || buf.st_size == 0) {
                unlink(fn);
        }
        return(0);
}

touch(fn)
        char *fn;
{
        int fd;
        if ((fd=creat(fn, 0600)) < 0) 
                return(errno);
        else close(fd);
        return(0);
}