diplodocus.org Git - nmh/blob - docs/historical/mh-nov-1983/subs/m_edit.c

   1 #include "mh.h"
   2 #include <sys/types.h>
   3 #include <sys/stat.h>
   4 #include <signal.h>
   5 #include <stdio.h>
   6 #include "strings.h"
   7
   8 struct msgs *mp;
   9
  10 char *rindex();
  11
  12 m_edit(ed, file, use, altmsg)
  13 char **ed, *file, *altmsg;
  14 int use;
  15 {
  16         /* Exec editor.  Normal exit returns 0.
  17          * To abort, returns -1.  To try again, returns -2
  18          */
  19
  20         static char *edsave;
  21         static int  reedit;
  22         struct stat stbuf;
  23         int retstat;
  24         register char *cp;
  25         int pid, wpid;
  26         int intr;
  27         union { int statint;
  28                 struct {char lobyte, hibyte;} statby;
  29         } status;
  30
  31         if(!reedit) {                   /* set initial editor */
  32                 if(!*ed && (*ed = m_find("editor")) == NULL)
  33                         *ed = sysed;
  34         } else
  35                 if(!*ed) {              /* no explicit editor */
  36                         *ed = edsave;
  37                         cp = rindex(*ed, '/');
  38                         if(cp == 0)
  39                                 cp = *ed;
  40                         cp = concat(cp, "-next", 0);
  41                         if((cp = m_find(cp)) != NULL)
  42                                 *ed = cp;
  43                 }
  44         intr = (int) signal(SIGINT, SIG_IGN);
  45         if((pid = fork()) == 0) {
  46                 if(altmsg) {
  47                         unlink("@");
  48                         link(altmsg, "@");    /* An easy handle on cur msg */
  49                 }
  50                 m_update();
  51                 fflush(stdout);
  52                 signal(SIGINT, (int (*)()) intr);
  53                 execlp(*ed, *ed, file, 0);
  54                 fprintf(stderr, "Can't exec the editor:  ");
  55                 perror(*ed);  done(-1);
  56         } else if(pid == -1) {
  57                 fprintf(stderr, "No forks!\n");
  58                 retstat = -1;
  59                 goto leave;
  60         } else
  61                 while((wpid = wait(&status)) != -1 && wpid != pid) ;
  62         signal(SIGINT, (int (*)()) intr);
  63         if(status.statint) {
  64                 if((status.statby.hibyte == -1) ||      /* Can't exec editor */
  65                    (reedit && !status.statby.lobyte)) { /*2nd edit.Aborted by user*/
  66                         retstat = -2;
  67                         goto leave;
  68                 }
  69                 fprintf(stderr, "[%s aborted--%s ", invo_name(), file);
  70                 if(!use && status.statby.hibyte) {      /* edit aborted by user */
  71                         unlink(file);
  72                         fprintf(stderr, "deleted]\n");
  73                 } else                          /* 'use' or system abort */
  74                         fprintf(stderr, "preserved]\n");
  75                 retstat = -2;
  76                 goto leave;
  77         }
  78         reedit++;
  79         retstat = 0;
  80         if(altmsg && !mp->msgflags&READONLY) {
  81                 stat("@", &stbuf);
  82                 if(stbuf.st_nlink == 1)  /*@'s been edited by Ned*/
  83                         if(unlink(altmsg) == -1 || link("@", altmsg) == -1){
  84                                 fprintf(stderr, "Can't update %s from @ file!\n",altmsg);
  85                                 retstat = 0;
  86                                 goto leave;
  87                         }
  88         }
  89  leave:
  90         edsave = getcpy(*ed);
  91         *ed = 0;
  92         unlink("@");          /* Remove this extra link */
  93         return(retstat);
  94 }