sys/src/cmd/p.c

   1 #include <u.h>
   2 #include <libc.h>
   3 #include <bio.h>
   4
   5 #define DEF     22      /* lines in chunk: 3*DEF == 66, #lines per nroff page */
   6
   7 Biobuf *cons;
   8 Biobuf bout;
   9
  10 int pglen = DEF;
  11
  12 void printfile(int);
  13
  14 void
  15 main(int argc, char *argv[])
  16 {
  17         int n;
  18         int f;
  19
  20         if((cons = Bopen("/dev/cons", OREAD)) == 0) {
  21                 fprint(2, "p: can't open /dev/cons\n");
  22                 exits("missing /dev/cons");
  23         }
  24         Blethal(cons, nil);
  25         Binit(&bout, 1, OWRITE);
  26         Blethal(&bout, nil);
  27         n = 0;
  28         while(argc > 1) {
  29                 --argc; argv++;
  30                 if(*argv[0] == '-'){
  31                         pglen = atoi(&argv[0][1]);
  32                         if(pglen <= 0)
  33                                 pglen = DEF;
  34                 } else {
  35                         n++;
  36                         f = open(argv[0], OREAD);
  37                         if(f < 0){
  38                                 fprint(2, "p: can't open %s - %r\n", argv[0]);
  39                                 continue;
  40                         }
  41                         printfile(f);
  42                         close(f);
  43                 }
  44         }
  45         if(n == 0)
  46                 printfile(0);
  47         exits(0);
  48 }
  49
  50 void
  51 printfile(int f)
  52 {
  53         int i, j, n;
  54         char *s, *cmd;
  55         Biobuf *b;
  56
  57         b = malloc(sizeof(Biobuf));
  58         Binit(b, f, OREAD);
  59         Blethal(b, nil);
  60         for(;;){
  61                 for(i=1; i <= pglen; i++) {
  62                         s = Brdline(b, '\n');
  63                         if(s == 0){
  64                                 n = Blinelen(b);
  65                                 if(n > 0)       /* line too long for Brdline */
  66                                         for(j=0; j<n; j++)
  67                                                 Bputc(&bout, Bgetc(b));
  68                                 else{           /* true EOF */
  69                                         free(b);
  70                                         return;
  71                                 }
  72                         }else{
  73                                 Bwrite(&bout, s, Blinelen(b)-1);
  74                                 if(i < pglen)
  75                                         Bwrite(&bout, "\n", 1);
  76                         }
  77                 }
  78                 Bflush(&bout);
  79             getcmd:
  80                 cmd = Brdline(cons, '\n');
  81                 if(cmd == 0 || *cmd == 'q')
  82                         exits(0);
  83                 cmd[Blinelen(cons)-1] = 0;
  84                 if(*cmd == '!'){
  85                         if(fork() == 0){
  86                                 dup(Bfildes(cons), 0);
  87                                 execl("/bin/rc", "rc", "-c", cmd+1, nil);
  88                         }
  89                         waitpid();
  90                         goto getcmd;
  91                 }
  92         }
  93 }