readlink: add -m and -f flags

This commit is contained in:
Tai Chi Minh Ralph Eastwood 2015-02-11 08:55:17 +00:00 committed by sin
parent 0fcad66c75
commit 28e26bc688

View File

@ -5,6 +5,7 @@
#include <stdio.h> #include <stdio.h>
#include <stdlib.h> #include <stdlib.h>
#include <string.h> #include <string.h>
#include <sys/stat.h>
#include "util.h" #include "util.h"
@ -17,17 +18,18 @@ usage(void)
int int
main(int argc, char *argv[]) main(int argc, char *argv[])
{ {
char buf[PATH_MAX]; char buf1[PATH_MAX], buf2[PATH_MAX], arg[PATH_MAX];
int nflag = 0; int nflag = 0;
int fflag = 0; int mefflag = 0;
ssize_t n; ssize_t n;
struct stat st;
char *p = arg, *lp = NULL, *b = buf1;
ARGBEGIN { ARGBEGIN {
case 'e':
case 'm': case 'm':
eprintf("not implemented\n"); case 'e':
case 'f': case 'f':
fflag = 1; mefflag = ARGC();
break; break;
case 'n': case 'n':
nflag = 1; nflag = 1;
@ -42,16 +44,54 @@ main(int argc, char *argv[])
if (strlen(argv[0]) > PATH_MAX - 1) if (strlen(argv[0]) > PATH_MAX - 1)
eprintf("path too long\n"); eprintf("path too long\n");
if (fflag) { #define SWAP_BUF() (b = (b == buf1 ? buf2 : buf1));
if (!realpath(argv[0], buf)) switch (mefflag) {
exit(1); case 'm':
} else { if (argv[0][0] == '/') { /* case when path is on '/' */
if ((n = readlink(argv[0], buf, sizeof(buf) - 1)) < 0) arg[0] = '/';
exit(1); arg[1] = '\0';
buf[n] = '\0'; p++;
} else if (!strchr(argv[0], '/')) { /* relative path */
arg[0] = '.';
arg[1] = '/';
arg[2] = '\0';
} else
arg[0] = '\0';
strncat(arg, argv[0], PATH_MAX);
while ((p = strchr(p, '/'))) {
*p = '\0';
if (!realpath(arg, b)) {
*p = '/';
goto mdone;
} }
SWAP_BUF();
printf("%s", buf); lp = p;
*p++ = '/';
}
if (!realpath(arg, b)) {
mdone:
SWAP_BUF();
if (lp) {
/* drop the extra '/' on root */
lp += (argv[0][0] == '/' &&
lp - arg == 1);
strncat(b, lp, PATH_MAX);
}
}
break;
case 'e':
if (stat(argv[0], &st) < 0)
exit(1);
case 'f':
if (!realpath(argv[0], b))
exit(1);
break;
default:
if ((n = readlink(argv[0], b, PATH_MAX - 1)) < 0)
exit(1);
b[n] = '\0';
}
printf("%s", b);
if (!nflag) if (!nflag)
putchar('\n'); putchar('\n');