From 24604d024a187dd06544ddbda880ab4bc4bcdb4d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jos=C3=A9=20Luis=20Lafuente?= <jose.lafuente@tweag.io>
Date: Tue, 9 Jan 2024 22:51:39 +0100
Subject: [PATCH] C API: fix docs build after rebase

---
 Makefile                       |  9 +++++++++
 Makefile.config.in             |  1 +
 configure.ac                   |  4 ++++
 doc/external-api/README.md     |  6 +++---
 doc/external-api/local.mk      | 16 ++--------------
 package.nix                    |  3 +++
 src/libstore/c/nix_api_store.h |  2 +-
 7 files changed, 23 insertions(+), 18 deletions(-)

diff --git a/Makefile b/Makefile
index d9efc8154..ae4a8f0a4 100644
--- a/Makefile
+++ b/Makefile
@@ -129,3 +129,12 @@ internal-api-html:
 	@echo "Internal API docs are disabled. Configure with '--enable-internal-api-docs', or avoid calling 'make internal-api-html'."
 	@exit 1
 endif
+
+ifeq ($(ENABLE_EXTERNAL_API_DOCS), yes)
+$(eval $(call include-sub-makefile, doc/external-api/local.mk))
+else
+.PHONY: external-api-html
+external-api-html:
+	@echo "External API docs are disabled. Configure with '--enable-external-api-docs', or avoid calling 'make external-api-html'."
+	@exit 1
+endif
diff --git a/Makefile.config.in b/Makefile.config.in
index d5c382630..7f517898c 100644
--- a/Makefile.config.in
+++ b/Makefile.config.in
@@ -12,6 +12,7 @@ ENABLE_BUILD = @ENABLE_BUILD@
 ENABLE_DOC_GEN = @ENABLE_DOC_GEN@
 ENABLE_FUNCTIONAL_TESTS = @ENABLE_FUNCTIONAL_TESTS@
 ENABLE_INTERNAL_API_DOCS = @ENABLE_INTERNAL_API_DOCS@
+ENABLE_EXTERNAL_API_DOCS = @ENABLE_EXTERNAL_API_DOCS@
 ENABLE_S3 = @ENABLE_S3@
 ENABLE_UNIT_TESTS = @ENABLE_UNIT_TESTS@
 GTEST_LIBS = @GTEST_LIBS@
diff --git a/configure.ac b/configure.ac
index c3823c01c..1d327d51d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -177,6 +177,10 @@ AC_ARG_ENABLE(internal-api-docs, AS_HELP_STRING([--enable-internal-api-docs],[Bu
   ENABLE_INTERNAL_API_DOCS=$enableval, ENABLE_INTERNAL_API_DOCS=no)
 AC_SUBST(ENABLE_INTERNAL_API_DOCS)
 
+AC_ARG_ENABLE(external-api-docs, AS_HELP_STRING([--enable-external-api-docs],[Build API docs for Nix's external unstable C interfaces]),
+  ENABLE_EXTERNAL_API_DOCS=$enableval, ENABLE_EXTERNAL_API_DOCS=no)
+AC_SUBST(ENABLE_EXTERNAL_API_DOCS)
+
 AS_IF(
   [test "$ENABLE_FUNCTIONAL_TESTS" == "yes" || test "$ENABLE_DOC_GEN" == "yes"],
   [NEED_PROG(jq, jq)])
diff --git a/doc/external-api/README.md b/doc/external-api/README.md
index ff0a30ff4..3fa1c55f9 100644
--- a/doc/external-api/README.md
+++ b/doc/external-api/README.md
@@ -48,7 +48,7 @@ int main() {
    return 0;
 }
 ```
- 
+
 **Usage:**
 ```ShellSession
 $ gcc main.c $(pkg-config nix-expr-c --libs --cflags) -o main
@@ -66,7 +66,7 @@ It will increment the argument if it is an integer and throw an error otherwise.
 #include <nix_api_util.h>
 #include <nix_api_expr.h>
 #include <nix_api_value.h>
- 
+
 void increment(void* user_data, nix_c_context* ctx, State* state, Value** args, Value* v) {
     nix_value_force(NULL, state, args[0]);
     if (nix_get_type(NULL, args[0]) == NIX_TYPE_INT) {
@@ -75,7 +75,7 @@ void increment(void* user_data, nix_c_context* ctx, State* state, Value** args,
       nix_set_err_msg(ctx, NIX_ERR_UNKNOWN, "First argument should be an integer.");
     }
 }
- 
+
 void nix_plugin_entry() {
   const char* args[] = {"n", NULL};
   PrimOp *p = nix_alloc_primop(NULL, increment, 1, "increment", args, "Example custom built-in function: increments an integer", NULL);
diff --git a/doc/external-api/local.mk b/doc/external-api/local.mk
index aa501198b..c739bdaf0 100644
--- a/doc/external-api/local.mk
+++ b/doc/external-api/local.mk
@@ -1,19 +1,7 @@
-.PHONY: external-api-html
-
-ifeq ($(external_api_docs), yes)
-
 $(docdir)/external-api/html/index.html $(docdir)/external-api/latex: $(d)/doxygen.cfg
 	mkdir -p $(docdir)/external-api
 	{ cat $< ; echo "OUTPUT_DIRECTORY=$(docdir)/external-api" ; } | doxygen -
 
-# Generate the HTML API docs for Nix's unstable external interfaces.
+# Generate the HTML API docs for Nix's unstable C bindings
+.PHONY: external-api-html
 external-api-html: $(docdir)/external-api/html/index.html
-
-else
-
-# Make a nicer error message
-external-api-html:
-	@echo "External API docs are disabled. Configure with '--enable-external-api-docs', or avoid calling 'make external-api-html'."
-	@exit 1
-
-endif
diff --git a/package.nix b/package.nix
index af4ca9b46..c9e50c399 100644
--- a/package.nix
+++ b/package.nix
@@ -184,6 +184,9 @@ in {
           ./doc/manual
         ] ++ lib.optionals enableInternalAPIDocs [
           ./doc/internal-api
+        ] ++ lib.optionals enableExternalAPIDocs [
+          ./doc/external-api
+        ] ++ lib.optionals (enableInternalAPIDocs || enableExternalAPIDocs) [
           # Source might not be compiled, but still must be available
           # for Doxygen to gather comments.
           ./src
diff --git a/src/libstore/c/nix_api_store.h b/src/libstore/c/nix_api_store.h
index 91abdb201..7732ade6b 100644
--- a/src/libstore/c/nix_api_store.h
+++ b/src/libstore/c/nix_api_store.h
@@ -109,7 +109,7 @@ bool nix_store_is_valid_path(nix_c_context * context, Store * store, StorePath *
 /**
  * @brief Realise a Nix store path
  *
- * Blocking, calls callback once for each realisedoutput
+ * Blocking, calls callback once for each realised output
  *
  * @param[out] context Optional, stores error information
  * @param[in] store Nix Store reference