From f23efbb66c1f7a4d165bc2f001dbf2a0b252821c Mon Sep 17 00:00:00 2001
From: Prem Chaitanya Prathi <chaitanyaprem@gmail.com>
Date: Wed, 6 Mar 2024 05:45:33 +0530
Subject: [PATCH] chore: support a non-callback version of reconcile_with_ids

---
 cpp/example/test.c       | 21 ++++++++++----
 cpp/negentropy_wrapper.c | 62 ++++++++++++++++++++++++++++++++++++++--
 cpp/negentropy_wrapper.h | 11 +++++++
 3 files changed, 85 insertions(+), 9 deletions(-)

diff --git a/cpp/example/test.c b/cpp/example/test.c
index 0fb7211..f3511db 100644
--- a/cpp/example/test.c
+++ b/cpp/example/test.c
@@ -102,13 +102,22 @@ int main(){
    printf("reconcile returned with output of len %zu \n", outSize);
    b3.len = outSize;
 
-   outSize = reconcile_with_ids(ngn_inst1, &b3, &rec_callback);
+   //outSize = reconcile_with_ids(ngn_inst1, &b3, &rec_callback);
+
+   result res;
+   reconcile_with_ids_no_cbk(ngn_inst1, &b3, &res);
+   printf("needIds count:%llu , haveIds count: %llu \n",res.need_ids_len, res.have_ids_len);
+
+   for (int i=0; i < res.need_ids_len ; i++) {
+      printf("need ID at %d :", i);
+      printHexBuffer(res.need_ids[i]);
+   }
+
+   for (int j=0; j < res.have_ids_len ; j++) {
+      printf("need ID at %d :", j);
+      printHexBuffer(res.have_ids[j]);
+   }
 
    free(b3.data);
    free(b4.data);
-   //b3.len = len;
-   //b3.data = (char*)malloc(len);
-
-   //reconcile_with_ids(ngn_inst1, &b3, )
-   
 }
\ No newline at end of file
diff --git a/cpp/negentropy_wrapper.c b/cpp/negentropy_wrapper.c
index f624a7f..5a14c37 100644
--- a/cpp/negentropy_wrapper.c
+++ b/cpp/negentropy_wrapper.c
@@ -74,7 +74,6 @@ void negentropy_setinitiator(void* negentropy){
 
 }
 
-
 bool storage_insert(void* storage, uint64_t createdAt, buffer* id){
     negentropy::storage::BTreeMem* lmdbStorage;
     lmdbStorage = reinterpret_cast<negentropy::storage::BTreeMem*>(storage);
@@ -88,7 +87,6 @@ bool storage_insert(void* storage, uint64_t createdAt, buffer* id){
     return lmdbStorage->insert(createdAt, data);
 }
 
-
 bool storage_erase(void* storage, uint64_t createdAt, buffer* id){
     negentropy::storage::BTreeMem* lmdbStorage;
     lmdbStorage = reinterpret_cast<negentropy::storage::BTreeMem*>(storage);
@@ -101,7 +99,6 @@ bool storage_erase(void* storage, uint64_t createdAt, buffer* id){
     return lmdbStorage->erase(createdAt, data);
 }
 
-
 size_t reconcile(void* negentropy, buffer* query, buffer* output){
     Negentropy<negentropy::storage::BTreeMem> *ngn_inst;
     ngn_inst = reinterpret_cast<Negentropy<negentropy::storage::BTreeMem>*>(negentropy);
@@ -171,3 +168,62 @@ int reconcile_with_ids(void* negentropy, buffer*  query,reconcile_cbk cbk, char*
     free(need_ids);
     return 0;
 }   
+
+void transform_with_alloc(std::vector<std::string> &from_ids, buffer* to_ids)
+{
+   for (int i=0; i < from_ids.size(); i ++){
+    to_ids[i].data = (unsigned char*) malloc(from_ids[i].size()*sizeof(unsigned char));  
+    to_ids[i].len = from_ids[i].size();
+    memcpy(to_ids[i].data, from_ids[i].c_str(),to_ids[i].len);
+   }
+}
+
+void reconcile_with_ids_no_cbk(void* negentropy, buffer*  query, result* result){
+    Negentropy<negentropy::storage::BTreeMem> *ngn_inst;
+    ngn_inst = reinterpret_cast<Negentropy<negentropy::storage::BTreeMem>*>(negentropy);
+
+    std::optional<std::string> out;
+    std::vector<std::string> haveIds, needIds;
+    try {
+        out = ngn_inst->reconcile(std::string_view(reinterpret_cast< char const* >(query->data), query->len), haveIds, needIds);
+
+        result->have_ids_len = haveIds.size();
+        result->need_ids_len = needIds.size();
+        result->have_ids = (buffer*)malloc(result->have_ids_len*sizeof(buffer));
+        result->need_ids = (buffer*)malloc(result->need_ids_len*sizeof(buffer));
+
+        std::cout << "have_ids_len:" << result->have_ids_len << "need_ids_len:" << result->need_ids_len << std::endl;
+
+        transform_with_alloc(haveIds, result->have_ids);
+        transform_with_alloc(needIds, result->need_ids);
+
+    } catch(negentropy::err e){
+        std::cout << "caught error "<< e.what() << std::endl;
+        //TODO:Find a way to return this error and cleanup partially allocated memory if any
+        return ;
+    }
+    buffer output = {0,NULL};
+    if (out) {
+        result->output.len = out.value().size();
+        result->output.data = (unsigned char*)malloc(out.value().size()*sizeof(unsigned char));
+        result->output.data = (unsigned char*)out.value().c_str();
+        std::cout << "reconcile_with_ids output of reconcile is, len:" << out.value().size() << ", output:";
+        printHexString(std::string_view(out.value()));
+    }
+    return ;
+}
+
+//Note: This function assumes that all relevant heap memory is alloced and just tries to free
+void free_result(result* r){
+    free((void *) r->output.data);
+    
+    for (int i = 0; i < r->have_ids_len; i++) {
+        free((void *) r->have_ids[i].data);
+    }
+    free((void *)r->have_ids);
+
+    for (int i = 0; i < r->need_ids_len; i++) {
+        free((void *) r->need_ids[i].data);
+    }
+    free((void *)r->need_ids);
+}
\ No newline at end of file
diff --git a/cpp/negentropy_wrapper.h b/cpp/negentropy_wrapper.h
index f3d0eac..dd3fd29 100644
--- a/cpp/negentropy_wrapper.h
+++ b/cpp/negentropy_wrapper.h
@@ -13,6 +13,14 @@ typedef struct _buffer_{
     unsigned char* data;
 }buffer;
 
+typedef struct _result_ {
+  buffer output;
+  uint64_t have_ids_len;
+  uint64_t need_ids_len;
+  buffer* have_ids;
+  buffer* need_ids;
+} result;
+
 //This is a C-wrapper for the C++ library that helps in integrating negentropy with nim code.
 //TODO: Do error handling by catching exceptions
 
@@ -34,6 +42,9 @@ EXTERNC typedef void (*reconcile_cbk)(buffer* have_ids, uint64_t have_ids_len, b
 
 EXTERNC int reconcile_with_ids(void* negentropy, buffer*  query, reconcile_cbk cbk, char* outptr);
 
+EXTERNC void reconcile_with_ids_no_cbk(void* negentropy, buffer*  query, result* result);
+
+EXTERNC void free_result(result* result);
 
 #endif