libexpr: add C bindings

src/libexpr/nix_api_expr.cc

@@ -0,0 +1,141 @@
+#include <cstring>
+#include <iostream>
+#include <stdexcept>
+#include <string>
+
+#include "config.hh"
+#include "eval.hh"
+#include "globals.hh"
+#include "util.hh"
+
+#include "nix_api_expr.h"
+#include "nix_api_expr_internal.h"
+#include "nix_api_store.h"
+#include "nix_api_store_internal.h"
+#include "nix_api_util.h"
+#include "nix_api_util_internal.h"
+
+#ifdef HAVE_BOEHMGC
+#define GC_INCLUDE_NEW 1
+#include "gc_cpp.h"
+#endif
+
+nix_err nix_libexpr_init(nix_c_context *context) {
+  if (context)
+    context->last_err_code = NIX_OK;
+  {
+    auto ret = nix_libutil_init(context);
+    if (ret != NIX_OK)
+      return ret;
+  }
+  {
+    auto ret = nix_libstore_init(context);
+    if (ret != NIX_OK)
+      return ret;
+  }
+  try {
+    nix::initGC();
+  }
+  NIXC_CATCH_ERRS
+}
+
+Expr *nix_parse_expr_from_string(nix_c_context *context, State *state,
+                                 const char *expr, const char *path,
+                                 GCRef *ref) {
+  if (context)
+    context->last_err_code = NIX_OK;
+  try {
+    Expr *result = state->state.parseExprFromString(
+        expr, state->state.rootPath(nix::CanonPath(path)));
+    if (ref)
+      ref->ptr = result;
+    return result;
+  }
+  NIXC_CATCH_ERRS_NULL
+}
+
+nix_err nix_expr_eval(nix_c_context *context, State *state, Expr *expr,
+                      Value *value) {
+  if (context)
+    context->last_err_code = NIX_OK;
+  try {
+    state->state.eval((nix::Expr *)expr, *(nix::Value *)value);
+  }
+  NIXC_CATCH_ERRS
+}
+
+nix_err nix_value_call(nix_c_context *context, State *state, Value *fn,
+                       Value *arg, Value *value) {
+  if (context)
+    context->last_err_code = NIX_OK;
+  try {
+    state->state.callFunction(*(nix::Value *)fn, *(nix::Value *)arg,
+                              *(nix::Value *)value, nix::noPos);
+  }
+  NIXC_CATCH_ERRS
+}
+
+nix_err nix_value_force(nix_c_context *context, State *state, Value *value) {
+  if (context)
+    context->last_err_code = NIX_OK;
+  try {
+    state->state.forceValue(*(nix::Value *)value, nix::noPos);
+  }
+  NIXC_CATCH_ERRS
+}
+
+nix_err nix_value_force_deep(nix_c_context *context, State *state,
+                             Value *value) {
+  if (context)
+    context->last_err_code = NIX_OK;
+  try {
+    state->state.forceValueDeep(*(nix::Value *)value);
+  }
+  NIXC_CATCH_ERRS
+}
+
+State *nix_state_create(nix_c_context *context, const char **searchPath_c,
+                        Store *store) {
+  if (context)
+    context->last_err_code = NIX_OK;
+  try {
+    nix::Strings searchPath;
+    if (searchPath_c != nullptr)
+      for (size_t i = 0; searchPath_c[i] != nullptr; i++)
+        searchPath.push_back(searchPath_c[i]);
+
+    return new State{
+        nix::EvalState(nix::SearchPath::parse(searchPath), store->ptr)};
+  }
+  NIXC_CATCH_ERRS_NULL
+}
+
+void nix_state_free(State *state) { delete state; }
+
+GCRef *nix_gc_ref(nix_c_context *context, void *obj) {
+  if (context)
+    context->last_err_code = NIX_OK;
+  try {
+#if HAVE_BOEHMGC
+    return new (NoGC) GCRef{obj};
+#else
+    return new GCRef{obj};
+#endif
+  }
+  NIXC_CATCH_ERRS_NULL
+}
+
+void nix_gc_free(GCRef *ref) {
+#if HAVE_BOEHMGC
+  GC_FREE(ref);
+#else
+  delete ref;
+#endif
+}
+
+void nix_gc_register_finalizer(void *obj, void *cd,
+                               void (*finalizer)(void *obj, void *cd)) {
+#ifdef HAVE_BOEHMGC
+  GC_REGISTER_FINALIZER(obj, finalizer, cd, 0, 0);
+#endif
+}