[hackers] [sbase] readlink: add -m and -f flags || Tai Chi Minh Ralph Eastwood

From: <git_AT_suckless.org>
Date: Wed, 11 Feb 2015 12:55:27 +0100 (CET)

commit 760d79be62c26493c86256c2b821e190657c3690
Author: Tai Chi Minh Ralph Eastwood <tcmreastwood_AT_gmail.com>
Date: Wed Feb 11 08:55:17 2015 +0000

    readlink: add -m and -f flags

diff --git a/readlink.c b/readlink.c
index 9c1479a..1089d06 100644
--- a/readlink.c
+++ b/readlink.c
_AT_@ -5,6 +5,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/stat.h>
 
 #include "util.h"
 
_AT_@ -17,17 +18,18 @@ usage(void)
 int
 main(int argc, char *argv[])
 {
- char buf[PATH_MAX];
+ char buf1[PATH_MAX], buf2[PATH_MAX], arg[PATH_MAX];
         int nflag = 0;
- int fflag = 0;
+ int mefflag = 0;
         ssize_t n;
+ struct stat st;
+ char *p = arg, *lp = NULL, *b = buf1;
 
         ARGBEGIN {
- case 'e':
         case 'm':
- eprintf("not implemented\n");
+ case 'e':
         case 'f':
- fflag = 1;
+ mefflag = ARGC();
                 break;
         case 'n':
                 nflag = 1;
_AT_@ -42,16 +44,54 @@ main(int argc, char *argv[])
         if (strlen(argv[0]) > PATH_MAX - 1)
                 eprintf("path too long\n");
 
- if (fflag) {
- if (!realpath(argv[0], buf))
- exit(1);
- } else {
- if ((n = readlink(argv[0], buf, sizeof(buf) - 1)) < 0)
- exit(1);
- buf[n] = '\0';
+#define SWAP_BUF() (b = (b == buf1 ? buf2 : buf1));
+ switch (mefflag) {
+ case 'm':
+ if (argv[0][0] == '/') { /* case when path is on '/' */
+ arg[0] = '/';
+ arg[1] = '\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();
+ 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", buf);
+ printf("%s", b);
         if (!nflag)
                 putchar('\n');
 
Received on Wed Feb 11 2015 - 12:55:27 CET