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         Binit(&bout, 1, OWRITE);
  25         n = 0;
  26         while(argc > 1) {
  27                 --argc; argv++;
  28                 if(*argv[0] == '-'){
  29                         pglen = atoi(&argv[0][1]);
  30                         if(pglen <= 0)
  31                                 pglen = DEF;
  32                 } else {
  33                         n++;
  34                         f = open(argv[0], OREAD);
  35                         if(f < 0){
  36                                 fprint(2, "p: can't open %s - %r\n", argv[0]);
  37                                 continue;
  38                         }
  39                         printfile(f);
  40                         close(f);
  41                 }
  42         }
  43         if(n == 0)
  44                 printfile(0);
  45         exits(0);
  46 }
  47
  48 void
  49 printfile(int f)
  50 {
  51         int i, j, n;
  52         char *s, *cmd;
  53         Biobuf *b;
  54
  55         b = malloc(sizeof(Biobuf));
  56         Binit(b, f, OREAD);
  57         for(;;){
  58                 for(i=1; i <= pglen; i++) {
  59                         s = Brdline(b, '\n');
  60                         if(s == 0){
  61                                 n = Blinelen(b);
  62                                 if(n > 0)       /* line too long for Brdline */
  63                                         for(j=0; j<n; j++)
  64                                                 Bputc(&bout, Bgetc(b));
  65                                 else{           /* true EOF */
  66                                         free(b);
  67                                         return;
  68                                 }
  69                         }else{
  70                                 Bwrite(&bout, s, Blinelen(b)-1);
  71                                 if(i < pglen)
  72                                         Bwrite(&bout, "\n", 1);
  73                         }
  74                 }
  75                 Bflush(&bout);
  76             getcmd:
  77                 cmd = Brdline(cons, '\n');
  78                 if(cmd == 0 || *cmd == 'q')
  79                         exits(0);
  80                 cmd[Blinelen(cons)-1] = 0;
  81                 if(*cmd == '!'){
  82                         if(fork() == 0){
  83                                 dup(Bfildes(cons), 0);
  84                                 execl("/bin/rc", "rc", "-c", cmd+1, nil);
  85                         }
  86                         waitpid();
  87                         goto getcmd;
  88                 }
  89         }
  90 }