From 781aa78ee25fca2bb27a9b724ae111f9581e63f7 Mon Sep 17 00:00:00 2001
From: Steve Muckle <smuckle@google.com>
Date: Thu, 1 Aug 2019 14:55:07 -0700
Subject: [PATCH] libmodprobe: add GetAllDependencies

Add a method to retrieve the dependencies (both hard and soft) of a
module.

Change-Id: Ie44ceb3e36856bb1a3e68c5d3c0d55a38deb0ef9
---
 libmodprobe/include/modprobe/modprobe.h |  3 +++
 libmodprobe/libmodprobe.cpp             | 33 +++++++++++++++++++++++++
 2 files changed, 36 insertions(+)

diff --git a/libmodprobe/include/modprobe/modprobe.h b/libmodprobe/include/modprobe/modprobe.h
index 913a7870b..0599ec538 100644
--- a/libmodprobe/include/modprobe/modprobe.h
+++ b/libmodprobe/include/modprobe/modprobe.h
@@ -30,6 +30,9 @@ class Modprobe {
                          const std::string& parameters = "");
     bool Remove(const std::string& module_name);
     std::vector<std::string> ListModules(const std::string& pattern);
+    bool GetAllDependencies(const std::string& module, std::vector<std::string>* pre_dependencies,
+                            std::vector<std::string>* dependencies,
+                            std::vector<std::string>* post_dependencies);
     void EnableBlacklist(bool enable);
 
   private:
diff --git a/libmodprobe/libmodprobe.cpp b/libmodprobe/libmodprobe.cpp
index 010624240..3e9001a0e 100644
--- a/libmodprobe/libmodprobe.cpp
+++ b/libmodprobe/libmodprobe.cpp
@@ -376,3 +376,36 @@ std::vector<std::string> Modprobe::ListModules(const std::string& pattern) {
     }
     return rv;
 }
+
+bool Modprobe::GetAllDependencies(const std::string& module,
+                                  std::vector<std::string>* pre_dependencies,
+                                  std::vector<std::string>* dependencies,
+                                  std::vector<std::string>* post_dependencies) {
+    std::string canonical_name = MakeCanonical(module);
+    if (pre_dependencies) {
+        pre_dependencies->clear();
+        for (const auto& [it_module, it_softdep] : module_pre_softdep_) {
+            if (canonical_name == it_module) {
+                pre_dependencies->emplace_back(it_softdep);
+            }
+        }
+    }
+    if (dependencies) {
+        dependencies->clear();
+        auto hard_deps = GetDependencies(canonical_name);
+        if (hard_deps.empty()) {
+            return false;
+        }
+        for (auto dep = hard_deps.rbegin(); dep != hard_deps.rend(); dep++) {
+            dependencies->emplace_back(*dep);
+        }
+    }
+    if (post_dependencies) {
+        for (const auto& [it_module, it_softdep] : module_post_softdep_) {
+            if (canonical_name == it_module) {
+                post_dependencies->emplace_back(it_softdep);
+            }
+        }
+    }
+    return true;
+}