Various fixes

optimized  nmbs_bitfield macros a little

.github/workflows/ci.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Clone repo
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       - name: configure
         run: |
           cmake -S . -B build -DBUILD_TESTS=ON -DCMAKE_BUILD_TYPE=Debug
@@ -19,7 +19,7 @@ jobs:
       - name: Compress Build Directory
         run: tar -czf build.tar.gz build/
       - name: Upload Build Artifact
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: build
           path: build.tar.gz
@@ -27,7 +27,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Clone repo
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
       - name: Build Arduino examples
         run: |
           mkdir -p build
@@ -60,7 +60,7 @@ jobs:
     steps:
       - uses: actions/checkout@v3
       - name: Download Build Directory
-        uses: actions/download-artifact@v3
+        uses: actions/download-artifact@v4
         with:
           name: build  
       - name: Extract Build Directory

CMakeLists.txt

@@ -12,14 +12,14 @@ include_directories(tests examples/linux .)
 add_library(nanomodbus nanomodbus.c)
 target_include_directories(nanomodbus PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})
 
-if(BUILD_EXAMPLES)
+if (BUILD_EXAMPLES)
     add_executable(client-tcp examples/linux/client-tcp.c)
     target_link_libraries(client-tcp nanomodbus)
     add_executable(server-tcp examples/linux/server-tcp.c)
     target_link_libraries(server-tcp nanomodbus)
-endif()
+endif ()
 
-if(BUILD_TESTS)
+if (BUILD_TESTS)
     add_executable(nanomodbus_tests nanomodbus.c tests/nanomodbus_tests.c)
     target_link_libraries(nanomodbus_tests pthread)
 
@@ -38,4 +38,4 @@ if(BUILD_TESTS)
     add_test(NAME test_server_disabled COMMAND $<TARGET_FILE:server_disabled>)
     add_test(NAME test_client_disabled COMMAND $<TARGET_FILE:client_disabled>)
     add_test(NAME test_multi_server_rtu COMMAND $<TARGET_FILE:multi_server_rtu>)
-endif()
+endif ()

README.md

@@ -114,7 +114,7 @@ FetchContent_Declare(
 
 FetchContent_MakeAvailable(nanomodbus)
 
-...
+#...
 
 add_executable(your_program source_codes)
 target_link_libraries(your_program nanomodbus)
@@ -187,4 +187,5 @@ Please refer to `examples/arduino/README.md` for more info about building and ru
         - `NMBS_SERVER_READ_WRITE_REGISTERS_DISABLED`
         - `NMBS_SERVER_READ_DEVICE_IDENTIFICATION_DISABLED`
     - `NMBS_STRERROR_DISABLED` to disable the code that converts `nmbs_error`s to strings
+    - `NMBS_BITFIELD_MAX` to set the size of the `nmbs_bitfield` type, used to store coil values (default is `2000`)
 - Debug prints about received and sent messages can be enabled by defining `NMBS_DEBUG`

nanomodbus.c

@@ -546,7 +546,7 @@ static nmbs_error recv_read_discrete_res(nmbs_t* nmbs, nmbs_bitfield values) {
     uint8_t coils_bytes = get_1(nmbs);
     NMBS_DEBUG_PRINT("b %d\t", coils_bytes);
 
-    if (coils_bytes > 250) {
+    if (coils_bytes > NMBS_BITFIELD_BYTES_MAX) {
         return NMBS_ERROR_INVALID_RESPONSE;
     }
 
@@ -1958,7 +1958,7 @@ nmbs_error nmbs_client_create(nmbs_t* nmbs, const nmbs_platform_conf* platform_c
 
 
 static nmbs_error read_discrete(nmbs_t* nmbs, uint8_t fc, uint16_t address, uint16_t quantity, nmbs_bitfield values) {
-    if (quantity < 1 || quantity > 2000)
+    if (quantity < 1 || quantity > NMBS_BITFIELD_MAX)
         return NMBS_ERROR_INVALID_ARGUMENT;
 
     if ((uint32_t) address + (uint32_t) quantity > ((uint32_t) 0xFFFF) + 1)
@@ -2126,7 +2126,7 @@ nmbs_error nmbs_write_multiple_registers(nmbs_t* nmbs, uint16_t address, uint16_
         return err;
 
     if (!nmbs->msg.broadcast)
-        return recv_write_single_register_res(nmbs, address, quantity);
+        return recv_write_multiple_registers_res(nmbs, address, quantity);
 
     return NMBS_ERROR_NONE;
 }

nanomodbus.h

@@ -78,11 +78,21 @@ typedef enum nmbs_error {
  */
 #define nmbs_error_is_exception(e) ((e) > 0 && (e) < 5)
 
+#ifndef NMBS_BITFIELD_MAX
+#define NMBS_BITFIELD_MAX 2000
+#endif
+
+/* check coil count divisible by 8 */
+#if ((NMBS_BITFIELD_MAX & 7) > 0)
+#error "NMBS_BITFIELD_MAX must be divisible by 8"
+#endif
+
+#define NMBS_BITFIELD_BYTES_MAX (NMBS_BITFIELD_MAX / 8)
 
 /**
  * Bitfield consisting of 2000 coils/discrete inputs
  */
-typedef uint8_t nmbs_bitfield[250];
+typedef uint8_t nmbs_bitfield[NMBS_BITFIELD_BYTES_MAX];
 
 /**
  * Bitfield consisting of 256 values
@@ -92,24 +102,22 @@ typedef uint8_t nmbs_bitfield_256[32];
 /**
  * Read a bit from the nmbs_bitfield bf at position b
  */
-#define nmbs_bitfield_read(bf, b) ((bool) ((bf)[(b) / 8] & (0x1 << ((b) % 8))))
+#define nmbs_bitfield_read(bf, b) ((bool) ((bf)[(b) >> 3] & (0x1 << ((b) & (8 - 1)))))
 
 /**
  * Set a bit of the nmbs_bitfield bf at position b
  */
-#define nmbs_bitfield_set(bf, b) (((bf)[(b) / 8]) = (((bf)[(b) / 8]) | (0x1 << ((b) % 8))))
+#define nmbs_bitfield_set(bf, b) (((bf)[(b) >> 3]) = (((bf)[(b) >> 3]) | (0x1 << ((b) & (8 - 1)))))
 
 /**
  * Reset a bit of the nmbs_bitfield bf at position b
  */
-#define nmbs_bitfield_unset(bf, b) (((bf)[(b) / 8]) = (((bf)[(b) / 8]) & ~(0x1 << ((b) % 8))))
+#define nmbs_bitfield_unset(bf, b) (((bf)[(b) >> 3]) = (((bf)[(b) >> 3]) & ~(0x1 << ((b) & (8 - 1)))))
 
 /**
  * Write value v to the nmbs_bitfield bf at position b
  */
-#define nmbs_bitfield_write(bf, b, v)                                                                                  \
-    (((bf)[(b) / 8]) = ((v) ? (((bf)[(b) / 8]) | (0x1 << ((b) % 8))) : (((bf)[(b) / 8]) & ~(0x1 << ((b) % 8)))))
-
+#define nmbs_bitfield_write(bf, b, v) ((bf)[(b) >> 3] = ((bf)[(b) >> 3] & ~(1 << ((b) & 7))) | ((v) << ((b) & 7)))
 /**
  * Reset (zero) the whole bitfield
  */