BSD 4_1c_2 release

[unix-history] / usr / src / ucb / apply.c

static char sccsid[] = "@(#)apply.c     4.2     (Berkeley)      2/9/83";

/*%cc -s -O %
* apply - apply a command to a set of arguments
*
*      apply echo * == ls
*      apply -2 cmp A1 B1 A2 B2   compares A's with B's
*      apply "ln %1 /usr/fred/dir" *  duplicates a directory
*/
#include <stdio.h>
char    *cmdp;
#define NCHARS 512
char    cmd[512];
char    defargs=1;
#define DEFARGCHAR      '%'
char    argchar=DEFARGCHAR;
int     nchars;
extern  char *getenv();

main(argc, argv)
       char *argv[];
{
       register n;
       while(argc>2 && argv[1][0]=='-'){
               if(argv[1][1]=='a'){
                       argchar=argv[1][2];
                       if(argchar=='\0')
                               argchar=DEFARGCHAR;
               } else {
                       defargs = atoi(&argv[1][1]);
                       if(defargs < 0)
                               defargs = 1;
               }
               --argc; ++argv;
       }
       if(argc<2){
               fprintf(stderr, "usage: apply [-14] [-a%] cmd arglist\n");
               exit(1);
       }
       argc -= 2;
       cmdp = argv[1];
       argv += 2;
       while(n=docmd(argc, argv)){
               argc -= n;
               argv += n;
       }
}
char
addc(c)
       char c;
{
       if(nchars++>=NCHARS){
               fprintf(stderr, "apply: command too long\n");
               exit(1);
       }
       return(c);
}
char *
addarg(s, t)
       register char *s, *t;
{
       while(*t = addc(*s++))
               *t++;
       return(t);
}
docmd(argc, argv)
       char *argv[];
{
       register char *p, *q;
       register max, i;
       char gotit;
       if(argc<=0)
               return(0);
       nchars = 0;
       max = 0;
       gotit = 0;
       p = cmdp;
       q = cmd;
       while(*q = addc(*p++)){
               if(*q++!=argchar || *p<'1' || '9'<*p)
                       continue;
               if((i= *p++-'1') > max)
                       max = i;
               if(i>=argc){
       Toofew:
                       fprintf(stderr, "apply: expecting argument(s) after `%s'\n", argv[argc-1]);
                       exit(1);
               }
               q = addarg(argv[i], q-1);
               gotit++;
       }
       if(defargs!=0 && gotit==0){
               if(defargs>argc)
                       goto Toofew;
               for(i=0; i<defargs; i++){
                       *q++ = addc(' ');
                       q = addarg(argv[i], q);
               }
       }
       i = system(cmd);
       if(i == 127){
               fprintf(stderr, "apply: no shell!\n");
               exit(1);
       }
       return(max==0? (defargs==0? 1 : defargs) : max+1);
}
system(s)
char *s;
{
       int status, pid, w;
       char *shell = getenv("SHELL");

       if ((pid = fork()) == 0) {
               execl(shell ? shell : "/bin/sh", "sh", "-c", s, 0);
               _exit(127);
       }
       if(pid == -1){
               fprintf(stderr, "apply: can't fork\n");
               exit(1);
       }
       while ((w = wait(&status)) != pid && w != -1)
               ;
       if (w == -1)
               status = -1;
       return(status);
}