Merge pull request #14254 from roberth/upstream-RossComputerGuy/feat/expose-computefsclosure

libstore-c: add nix_store_get_fs_closure #14025 with tests and realise error fix

Author: Ericson2314

src/libstore-c/nix_api_store.cc

@@ -126,6 +126,36 @@ StorePath * nix_store_parse_path(nix_c_context * context, Store * store, const c
     NIXC_CATCH_ERRS_NULL
 }
 
+nix_err nix_store_get_fs_closure(
+    nix_c_context * context,
+    Store * store,
+    const StorePath * store_path,
+    bool flip_direction,
+    bool include_outputs,
+    bool include_derivers,
+    void * userdata,
+    void (*callback)(nix_c_context * context, void * userdata, const StorePath * store_path))
+{
+    if (context)
+        context->last_err_code = NIX_OK;
+    try {
+        const auto nixStore = store->ptr;
+
+        nix::StorePathSet set;
+        nixStore->computeFSClosure(store_path->path, set, flip_direction, include_outputs, include_derivers);
+
+        if (callback) {
+            for (const auto & path : set) {
+                const StorePath tmp{path};
+                callback(context, userdata, &tmp);
+                if (context && context->last_err_code != NIX_OK)
+                    return context->last_err_code;
+            }
+        }
+    }
+    NIXC_CATCH_ERRS
+}
+
 nix_err nix_store_realise(
     nix_c_context * context,
     Store * store,
@@ -143,6 +173,14 @@ nix_err nix_store_realise(
         const auto nixStore = store->ptr;
         auto results = nixStore->buildPathsWithResults(paths, nix::bmNormal, nixStore);
 
+        assert(results.size() == 1);
+
+        // Check if any builds failed
+        for (auto & result : results) {
+            if (auto * failureP = result.tryGetFailure())
+                failureP->rethrow();
+        }
+
         if (callback) {
             for (const auto & result : results) {
                 if (auto * success = result.tryGetSuccess()) {

src/libstore-c/nix_api_store.h

@@ -186,6 +186,8 @@ nix_err nix_store_real_path(
  * @param[in] path Path to build
  * @param[in] userdata data to pass to every callback invocation
  * @param[in] callback called for every realised output
+ * @return NIX_OK if the build succeeded, or an error code if the build/scheduling/outputs/copying/etc failed.
+ *         On error, the callback is never invoked and error information is stored in context.
  */
 nix_err nix_store_realise(
     nix_c_context * context,
@@ -245,6 +247,35 @@ void nix_derivation_free(nix_derivation * drv);
  */
 nix_err nix_store_copy_closure(nix_c_context * context, Store * srcStore, Store * dstStore, StorePath * path);
 
+/**
+ * @brief Gets the closure of a specific store path
+ *
+ * @note The callback borrows each StorePath only for the duration of the call.
+ *
+ * @param[out] context Optional, stores error information
+ * @param[in] store nix store reference
+ * @param[in] store_path The path to compute from
+ * @param[in] flip_direction If false, compute the forward closure (paths referenced by any store path in the closure).
+ *                           If true, compute the backward closure (paths that reference any store path in the closure).
+ * @param[in] include_outputs If flip_direction is false: for any derivation in the closure, include its outputs.
+ *                            If flip_direction is true: for any output in the closure, include derivations that produce
+ *                            it.
+ * @param[in] include_derivers If flip_direction is false: for any output in the closure, include the derivation that
+ *                             produced it.
+ *                             If flip_direction is true: for any derivation in the closure, include its outputs.
+ * @param[in] callback The function to call for every store path, in no particular order
+ * @param[in] userdata The userdata to pass to the callback
+ */
+nix_err nix_store_get_fs_closure(
+    nix_c_context * context,
+    Store * store,
+    const StorePath * store_path,
+    bool flip_direction,
+    bool include_outputs,
+    bool include_derivers,
+    void * userdata,
+    void (*callback)(nix_c_context * context, void * userdata, const StorePath * store_path));
+
 // cffi end
 #ifdef __cplusplus
 }