Larry suggested using concat_path_file() would be an even safer bet

for 'which'.  I ageed, so I whipped this up -- which revealed a bug in
concat_path_file.  It turns out that that a '/' can be appended from
either the path _or_ the filename, but only the former was checked.
 -Erik

3 files changed, 9 insertions, 9 deletions

diff --git a/findutils/which.c b/findutils/which.c
index 08813c149..1e5e9eed5 100644
--- a/findutils/which.c
+++ b/findutils/which.c
@@ -53,10 +53,9 @@ extern int which_main(int argc, char **argv)
                 argv++;
                 found = 0;
                 for (i = 0; i < count; i++) {
-                        char buf[strlen(path_n)+strlen(*argv)+2];
-                        strcpy (buf, path_n);
-                        strcat (buf, "/");
-                        strcat (buf, *argv);
+                        char *buf;
+                        buf = concat_path_file(buf, path_n);
+                        buf = concat_path_file(buf, *argv);
                         if (stat (buf, &filestat) == 0
                             && filestat.st_mode & S_IXUSR)
                         {
diff --git a/libbb/concat_path_file.c b/libbb/concat_path_file.c
index d53dc0e2e..ce92310ea 100644
--- a/libbb/concat_path_file.c
+++ b/libbb/concat_path_file.c
@@ -15,9 +15,11 @@ extern char *concat_path_file(const char *path, const char *filename)
         int  flg_slash = 1;
 
         l = strlen(path);
-        if(l>0 && path[l-1] == '/')
+        if (l>0 && path[l-1] == '/')
                 flg_slash--;
         l += strlen(filename);
+        if (l>0 && filename[0] == '/')
+                flg_slash--;
         outbuf = xmalloc(l+1+flg_slash);
         sprintf(outbuf, (flg_slash ? "%s/%s" : "%s%s"), path, filename);
         return outbuf;
diff --git a/which.c b/which.c
index 08813c149..1e5e9eed5 100644
--- a/which.c
+++ b/which.c
@@ -53,10 +53,9 @@ extern int which_main(int argc, char **argv)
                 argv++;
                 found = 0;
                 for (i = 0; i < count; i++) {
-                        char buf[strlen(path_n)+strlen(*argv)+2];
-                        strcpy (buf, path_n);
-                        strcat (buf, "/");
-                        strcat (buf, *argv);
+                        char *buf;
+                        buf = concat_path_file(buf, path_n);
+                        buf = concat_path_file(buf, *argv);
                         if (stat (buf, &filestat) == 0
                             && filestat.st_mode & S_IXUSR)
                         {