BSD 2 development

[unix-history] / .ref-BSD-1 / pi / main.c

#
/*
* pi - Pascal interpreter code translator
*
* Charles Haley, Bill Joy UCB
* Version 1.0 August 1977
*/

#include "whoami"
#include "0.h"

/*
* This program is described in detail in the "PI 1.0 Implementation Notes"
*
* This version of pi has been in use at Berkeley since May 1977
* and is very stable, except for the syntactic error recovery which
* has just been written.  Please report any problems with the error
* recovery to the second author at the address given in the file
* READ_ME.  The second author takes full responsibility for any bugs
* in the syntactic error recovery.
*/

char    piusage[]       "pi [ -blnpstuw ] [ -i file ... ] name.p";
char    pixusage[]      "pix [ -blnpstuw ] [ -i file ... ] name.p [ arg ... ]";

char    *usageis        piusage;
char    *obj            "obj";
/*
* Be careful changing errfile and howfile.
* There are the "magic" constants 9 and 15 immediately below.
*/
char    *errfile        "/usr/lib/pi_strings";
char    *howfile        "/usr/lib/how_pi\0";

int     onintr();

extern  int ibuf[259];

extern  char *lastname;

/*
* Main program for pi.
* Process options, then call yymain
* to do all the real work.
*/
main(argc, argv)
       int argc;
       char *argv[];
{
       register char *cp;
       register c;
       int i;

       if (argv[0][0] == 'a')
               errfile =+ 9, howfile =+ 9;
       if (argv[0][0] == '-' && argv[0][1] == 'o') {
               obj = &argv[0][2];
               usageis = pixusage;
               howfile[15] = 'x';
               ofil = 3;
       } else {
               ofil = creat(obj, 0755);
               if (ofil < 0) {
                       perror(obj);
                       pexit(NOSTART);
               }
       }
       argv++, argc--;
       if (argc == 0) {
               i = fork();
               if (i == -1)
                       goto usage;
               if (i == 0) {
                       execl("/bin/cat", "cat", howfile, 0);
                       goto usage;
               }
               while (wait(&i) != -1)
                       continue;
               pexit(NOSTART);
       }
       opt('p') = opt('t') = opt('b') = 1;
       while (argc > 0) {
               cp = argv[0];
               if (*cp++ != '-')
                       break;
               while (c = *cp++) switch (c) {
#ifdef DEBUG
                       case 'c':
                       case 'r':
                       case 'y':
                               togopt(c);
                               continue;
                       case 'C':
                               yycosts();
                               pexit(NOSTART);
                       case 'A':
                               testtrace++;
                       case 'F':
                               fulltrace++;
                       case 'E':
                               errtrace++;
                               opt('r')++;
                               continue;
                       case 'U':
                               yyunique = 0;
                               continue;
#endif
                       case 'b':
                               opt('b') = 2;
                               continue;
                       case 'i':
                               pflist = argv + 1;
                               pflstc = 0;
                               while (argc > 1) {
                                       if (dotted(argv[1], 'p'))
                                               break;
                                       pflstc++, argc--, argv++;
                               }
                               if (pflstc == 0)
                                       goto usage;
                               continue;
                       case 'l':
                       case 'n':
                       case 'p':
                       case 's':
                       case 't':
                       case 'u':
                       case 'w':
                               togopt(c);
                               continue;
                       case 'z':
                               monflg++;
                               continue;
                       default:
usage:
                               Perror( "Usage", usageis);
                               pexit(NOSTART);
               }
               argc--, argv++;
       }
       if (argc != 1)
               goto usage;
       efil = open(errfile, 0);
       if (efil < 0)
               perror(errfile), pexit(NOSTART);
       filename = argv[0];
       if (!dotted(filename, 'p')) {
               Perror(filename, "Name must end in '.p'");
               pexit(NOSTART);
       }
       close(0);
       if (fopen(filename, ibuf) < 0)
               perror(filename), pexit(NOSTART);
       if ((signal(2, 1) & 01) == 0)
               signal(2, onintr);
       if (opt('l')) {
               opt('n')++;
               yysetfile(filename);
               opt('n')--;
       } else
               lastname = filename;
       yymain();
       /* No return */
}

/*
* Buffer for putchar
*/
char    pcbuf[128];
char    *pcbp pcbuf;

/*
* Line buffered putchar for pi.
*/
putchar(c)
       char c;
{

       *pcbp++ = c;
       if (c == '\n' || pcbp == &pcbuf[sizeof pcbuf-1]) {
               write(1, &pcbuf, pcbp-pcbuf);
               pcbp = pcbuf;
       }
}

char    ugh[]   "Fatal error in pi\n";
/*
* Exit from the Pascal system.
* We throw in an ungraceful termination
* message if c > 1 indicating a severe
* error such as running out of memory
* or an internal inconsistency.
*/
pexit(c)
       int c;
{

       if (opt('l') && c != DIED && c != NOSTART)
               while (getline() != -1)
                       continue;
       yyflush();
       switch (c) {
               case DIED:
                       write(2, ugh, sizeof ugh);
               case NOSTART:
               case ERRS:
                       if (ofil > 0)
                               unlink(obj);
                       break;
               case AOK:
                       pflush();
                       break;
       }
       exit(c);
}

onintr()
{

       signal(2, 1);
       pexit(NOSTART);
}

/*
* Get an error message from the error message file
*/
geterr(seekpt, buf)
       int seekpt;
       char *buf;
{

       if (seek(efil, seekpt, 0) || read(efil, buf, 256) <= 0)
               perror(errfile), pexit(DIED);
}

header()
{
       extern char version[];
       static char anyheaders;

       gettime();
       if (anyheaders && opt('n'))
               putchar('\f');
       anyheaders++;
       printf("UNIX Pascal PI -- Version 1.0 (%s)\n\n%s  %s\n\n", version, myctime(tvec), filename);
}