execable.c: forgot to do "svn add" again...

diff --git a/libbb/execable.c b/libbb/execable.c
new file mode 100644 (file)
index 0000000..cb56b91
--- /dev/null
+++ b/libbb/execable.c
@@ -0,0 +1,62 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) 2006 Gabriel Somlo <somlo at cmu.edu>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ */
+
+#include "libbb.h"
+
+/* check if path points to an executable file;
+ * return 1 if found;
+ * return 0 otherwise;
+ */
+int execable_file(const char *name)
+{
+       struct stat s;
+       return (!access(name, X_OK) && !stat(name, &s) && S_ISREG(s.st_mode));
+}
+
+/* search $PATH for an executable file;
+ * return allocated string containing full path if found;
+ * return NULL otherwise;
+ */
+char *find_execable(const char *filename)
+{
+       char *path, *p, *n;
+
+       p = path = xstrdup(getenv("PATH") ? : "");
+       while (p) {
+               n = strchr(p, ':');
+               if (n)
+                       *n++ = '\0';
+               if (*p != '\0') { /* it's not a PATH="foo::bar" situation */
+                       p = concat_path_file(p, filename);
+                       if (execable_file(p)) {
+                               free(path);
+                               return p;
+                       }
+                       free(p);
+               }
+               p = n;
+       }
+       free(path);
+       return NULL;
+}
+
+/* search $PATH for an executable file;
+ * return 1 if found;
+ * return 0 otherwise;
+ */
+int exists_execable(const char *filename)
+{
+       char *ret = find_execable(filename);
+       if (ret) {
+               free(ret);
+               return 1;
+       }
+       return 0;
+}
+