Use /proc/self/exe to deduce the correct path. (#7908)

1 files changed, 13 insertions, 7 deletions

diff --git a/projects/ruby/fuzz_ruby_gems.c b/projects/ruby/fuzz_ruby_gems.c
index a627839d..7f955b58 100644
--- a/projects/ruby/fuzz_ruby_gems.c
+++ b/projects/ruby/fuzz_ruby_gems.c
@@ -251,16 +251,22 @@ static init_TargetFunction_ptr init_functions[] = {
 // will work.
 static int setenv_rubylib() {
   char rubylib[0x1000];
-  char cwd[PATH_MAX];
-  const char *outpath = getenv("OUT");
+  char exepath[PATH_MAX];
 
-  getcwd(cwd, sizeof(cwd));
-  if (!outpath) {
-    outpath = cwd;
-  }
+  // Deduce the location of the OUT directory from the executable path.
+  ssize_t n = readlink("/proc/self/exe", exepath, sizeof(exepath));
+
+  // Find the parent directory.
+  do {
+    if (n <= 0) {
+      return -1;
+    }
+  } while(exepath[--n] != '/');
+  exepath[n] = '\0';
+  fprintf(stderr, "exepath = %s\n", exepath);
 
   // init_ruby_load_paths() is automatically generated by build.sh
-  const int r = init_ruby_load_paths(rubylib, sizeof(rubylib), outpath);
+  const int r = init_ruby_load_paths(rubylib, sizeof(rubylib), exepath);
   if (r < 0 || (size_t)r >= sizeof(rubylib)) {
     return -1;
   }