From 765081325adaa32b8e6b7cee6b6400a63465d5d1 Mon Sep 17 00:00:00 2001
From: Lawrence Nahum <lawrence@greenaddress.it>
Date: Wed, 15 May 2024 16:57:34 +0200
Subject: [PATCH] remove some unnecessary wrapper functions

---
 src/bytewords.cpp        |  9 +++++++++
 src/fountain-decoder.cpp |  3 ++-
 src/fountain-encoder.cpp |  3 ++-
 src/utils.cpp            | 24 ------------------------
 src/utils.hpp            |  4 ----
 src/xoshiro256.cpp       |  8 +++++++-
 6 files changed, 20 insertions(+), 31 deletions(-)

diff --git a/src/bytewords.cpp b/src/bytewords.cpp
index e599882..d792856 100644
--- a/src/bytewords.cpp
+++ b/src/bytewords.cpp
@@ -9,6 +9,8 @@
 #include "utils.hpp"
 #include <stdexcept>
 #include <algorithm>
+#include <cstring>
+#include <esp_crc.h>
 
 namespace ur {
 
@@ -124,6 +126,13 @@ static string encode(const ByteVector& buf, const string& separator) {
     return join(words, separator);
 }
 
+static inline ByteVector crc32_bytes(const ByteVector &buf) {
+    uint32_t checksum = __builtin_bswap32(esp_crc32_le(0, buf.data(), buf.size()));
+    ByteVector result(sizeof(checksum));
+    std::memcpy(result.data(), &checksum, sizeof(checksum));
+    return result;
+}
+
 static ByteVector add_crc(const ByteVector& buf) {
     auto crc_buf = crc32_bytes(buf);
     auto result = buf;
diff --git a/src/fountain-decoder.cpp b/src/fountain-decoder.cpp
index f191c7c..22e936a 100644
--- a/src/fountain-decoder.cpp
+++ b/src/fountain-decoder.cpp
@@ -11,6 +11,7 @@
 #include <string>
 #include <cmath>
 #include <numeric>
+#include <esp_crc.h>
 
 using namespace std;
 
@@ -143,7 +144,7 @@ void FountainDecoder::process_simple_part(Part& p) {
         auto message = join_fragments(fragments, *_expected_message_len);
 
         // Verify the message checksum and note success or failure
-        auto checksum = crc32_int(message);
+        auto checksum = esp_crc32_le(0, message.data(), message.size());
         if(checksum == _expected_checksum) {
             result_ = message;
         } else {
diff --git a/src/fountain-encoder.cpp b/src/fountain-encoder.cpp
index 461c666..c52e852 100644
--- a/src/fountain-encoder.cpp
+++ b/src/fountain-encoder.cpp
@@ -12,6 +12,7 @@
 #include <vector>
 #include <limits>
 #include <cbor.h>
+#include <esp_crc.h>
 using namespace std;
 
 namespace ur {
@@ -177,7 +178,7 @@ ByteVector FountainEncoder::Part::cbor() const {
 FountainEncoder::FountainEncoder(const ByteVector& message, size_t max_fragment_len, uint32_t first_seq_num, size_t min_fragment_len) {
     assert(message.size() <= std::numeric_limits<uint32_t>::max());
     message_len_ = message.size();
-    checksum_ = crc32_int(message);
+    checksum_ = esp_crc32_le(0, message.data(), message.size());
     fragment_len_ = find_nominal_fragment_length(message_len_, min_fragment_len, max_fragment_len);
     fragments_ = partition_message(message, fragment_len_);
     seq_num_ = first_seq_num;
diff --git a/src/utils.cpp b/src/utils.cpp
index 0b00b0b..1c734a4 100644
--- a/src/utils.cpp
+++ b/src/utils.cpp
@@ -11,36 +11,12 @@
 #include <vector>
 #include <algorithm>
 #include <cctype>
-#include <mbedtls/sha256.h>
-#include <esp_crc.h>
 
 
 using namespace std;
 
 namespace ur {
 
-#define SHA256_LEN 32
-
-void sha256(const ByteVector &buf, std::array<uint8_t, SHA256_LEN> &digest) {
-    mbedtls_sha256_context ctx;
-    mbedtls_sha256_init(&ctx);
-    mbedtls_sha256_starts(&ctx, 0);
-    mbedtls_sha256_update(&ctx, buf.data(), buf.size());
-    mbedtls_sha256_finish(&ctx, digest.data());
-    mbedtls_sha256_free(&ctx);
-}
-
-ByteVector crc32_bytes(const ByteVector &buf) {
-    uint32_t checksum = __builtin_bswap32(crc32_int(buf));
-    auto *cbegin = (uint8_t*)&checksum;
-    auto *cend = cbegin + sizeof(uint32_t);
-    return {cbegin, cend};
-}
-
-uint32_t crc32_int(const ByteVector &buf) {
-    return esp_crc32_le(0, buf.data(), buf.size());
-}
-
 ByteVector string_to_bytes(const string& s) {
     return {s.begin(), s.end()};
 }
diff --git a/src/utils.hpp b/src/utils.hpp
index 43fa2cf..cfe5190 100644
--- a/src/utils.hpp
+++ b/src/utils.hpp
@@ -23,10 +23,6 @@ using ByteVector = std::vector<uint8_t, PSRAMAllocator<uint8_t>>;
 using ByteVectorVector = std::vector<ByteVector, PSRAMAllocator<ByteVector>>;
 using StringVector = std::vector<std::string, PSRAMAllocator<std::string>>;
 
-void sha256(const ByteVector &buf, std::array<uint8_t, 32> &digest);
-ByteVector crc32_bytes(const ByteVector &buf);
-uint32_t crc32_int(const ByteVector &buf);
-
 ByteVector string_to_bytes(const std::string& s);
 
 std::string data_to_hex(const ByteVector& in);
diff --git a/src/xoshiro256.cpp b/src/xoshiro256.cpp
index 90e7a90..eb3b1fd 100644
--- a/src/xoshiro256.cpp
+++ b/src/xoshiro256.cpp
@@ -8,6 +8,7 @@
 #include "xoshiro256.hpp"
 #include <limits>
 #include <cstring>
+#include <mbedtls/sha256.h>
 
 /*  Written in 2018 by David Blackman and Sebastiano Vigna (vigna@acm.org)
 
@@ -55,7 +56,12 @@ void Xoshiro256::set_s(const std::array<uint8_t, 32>& a) {
 
 void Xoshiro256::hash_then_set_s(const ByteVector& bytes) {
     std::array<uint8_t, 32> a;
-    sha256(bytes, a);
+    mbedtls_sha256_context ctx;
+    mbedtls_sha256_init(&ctx);
+    mbedtls_sha256_starts(&ctx, 0);
+    mbedtls_sha256_update(&ctx, bytes.data(), bytes.size());
+    mbedtls_sha256_finish(&ctx, a.data());
+    mbedtls_sha256_free(&ctx);
     set_s(a);
 }