feature (syscalls): changed 'nx_fread' and 'nx_fwrite' to match updated sysabi

inc/drivers/fs/ramfs.h

@@ -5,9 +5,9 @@
 
 #include "drivers/fs/vfs.h"
 
-void ramfs_file_delete  (vfs_node_T* node);
+void     ramfs_file_delete  (vfs_node_T* node);
-void ramfs_file_write   (vfs_node_T* node, uint64_t size, uint8_t* buffer_in);
+uint64_t ramfs_file_write   (vfs_node_T* node, uint64_t size, uint8_t* buffer_in);
-void ramfs_file_read    (vfs_node_T* node, uint64_t size, uint8_t* buffer_out);
+uint64_t ramfs_file_read    (vfs_node_T* node, uint64_t size, uint8_t* buffer_out);
 
 
 #endif //NOX_RAMFS_H

inc/drivers/fs/vfs.h

@@ -65,8 +65,8 @@ vfs_node_T*         vfs_node_resolve_child      (vfs_node_T* node, string_t chil
 
 vfs_node_T*         vfs_file_create             (fs_T* filesystem, string_t path);
 void                vfs_file_delete             (vfs_node_T* file);
-void                vfs_file_write              (vfs_node_T* file, uint64_t position, uint64_t size, uint8_t* buffer_in);
+uint64_t            vfs_file_write              (vfs_node_T* file, uint64_t position, uint64_t size, uint8_t* buffer_in);
-void                vfs_file_read               (vfs_node_T* file, uint64_t position, uint64_t size, uint8_t* buffer_out);
+uint64_t            vfs_file_read               (vfs_node_T* file, uint64_t position, uint64_t size, uint8_t* buffer_out);
 
 vfs_node_T*         vfs_directory_create        (fs_T* filesystem, string_t path);
 void                vfs_directory_delete        (vfs_node_T* directory);

src/drivers/fs/ramfs.c

@@ -10,7 +10,7 @@ void ramfs_file_delete(vfs_node_T* node) {
     vfs_node_cache_destruct(node->cache);
 }
 
-void ramfs_file_write(vfs_node_T* node, uint64_t size, uint8_t* buffer_in) {
+uint64_t ramfs_file_write(vfs_node_T* node, uint64_t size, uint8_t* buffer_in) {
     if (node->cache != NULL) {
         vfs_node_cache_destruct(node->cache);
     }
@@ -18,10 +18,13 @@ void ramfs_file_write(vfs_node_T* node, uint64_t size, uint8_t* buffer_in) {
     vfs_node_cache_create(node, size);
 
     memory_copy(buffer_in, node->cache->buffer, size);
+
+    return size;
 }
 
-void ramfs_file_read(vfs_node_T* node, uint64_t size, uint8_t* buffer_out) {
+uint64_t ramfs_file_read(vfs_node_T* node, uint64_t size, uint8_t* buffer_out) {
-    if (node->cache == NULL) { return; }
+    if (node->cache == NULL) { return 0; }
 
     memory_copy(node->cache->buffer, buffer_out, MIN(size, node->cache->buffer_size));
+    return size;
 }

src/drivers/fs/vfs.c

@@ -224,31 +224,33 @@ void vfs_file_delete(vfs_node_T* file) {
     vfs_node_destruct(file);
 }
 
-void vfs_file_write(vfs_node_T* file, uint64_t position, uint64_t size, uint8_t* buffer_in) {
+uint64_t vfs_file_write(vfs_node_T* file, uint64_t position, uint64_t size, uint8_t* buffer_in) {
     // in future this probably isn't a good way to determine the size of a file:
     file->size = size;
 
     switch (file->filesystem->type) {
         case FS_RAMFS: {
-            ramfs_file_write(file, size, buffer_in);
+            return ramfs_file_write(file, size, buffer_in);
-            break;
         }
         default: {
             break;
         }
     }
+
+    return 0;
 }
 
-void vfs_file_read(vfs_node_T* file, uint64_t position, uint64_t size, uint8_t* buffer_out) {
+uint64_t vfs_file_read(vfs_node_T* file, uint64_t position, uint64_t size, uint8_t* buffer_out) {
     switch (file->filesystem->type) {
         case FS_RAMFS: {
-            ramfs_file_read(file, size, buffer_out);
+            return ramfs_file_read(file, size, buffer_out);
-            break;
         }
         default: {
             break;
         }
     }
+
+    return 0;
 }
 
 vfs_node_T* vfs_directory_create(fs_T* filesystem, string_t path) {

src/platform/syscall.c

@@ -44,28 +44,23 @@ void syscall_handle_nx_fread(cpu_state_T* state) {
         case FILE_DESCRIPTOR_INVALID:
         case FILE_DESCRIPTOR_STDOUT:
         case FILE_DESCRIPTOR_STDERR: {
-            state->rax = STATUS_RESOURCE_NOT_AVAILABLE;
             break;
         }
 
         case FILE_DESCRIPTOR_STDIN: {
             read_bytes = pipe_read(&process->stdin, mem, n);
-            state->rax = STATUS_SUCCESS;
             break;
         }
 
         default: {
             vfs_node_T* node = file_descriptor_resolve(scheduler_get_current_process()->fd_array, fd);
 
-            // TODO: set read_bytes
+            read_bytes = vfs_file_read(node, offset, n, mem);
-
-            vfs_file_read(node, offset, n, mem);
-
-            state->rax = STATUS_SUCCESS;
             break;
         }
     }
-    // TODO: return read_bytes to process
+
+    state->rax = read_bytes;
 }
 
 void syscall_handle_nx_fwrite(cpu_state_T* state) {
@@ -80,7 +75,6 @@ void syscall_handle_nx_fwrite(cpu_state_T* state) {
     switch (fd) {
         case FILE_DESCRIPTOR_INVALID:
         case FILE_DESCRIPTOR_STDIN: {
-            state->rax = STATUS_RESOURCE_NOT_AVAILABLE;
             break;
         }
 
@@ -88,8 +82,6 @@ void syscall_handle_nx_fwrite(cpu_state_T* state) {
             if (process->stderr != NULL) {
                 written_bytes = pipe_write(process->stderr, mem, n);
             }
-
-            state->rax = STATUS_SUCCESS;
             break;
         }
 
@@ -97,23 +89,18 @@ void syscall_handle_nx_fwrite(cpu_state_T* state) {
             if (process->stdout != NULL) {
                 written_bytes = pipe_write(process->stdout, mem, n);
             }
-
-            state->rax = STATUS_SUCCESS;
             break;
         }
 
         default: {
             vfs_node_T* node = file_descriptor_resolve(scheduler_get_current_process()->fd_array, fd);
 
-            // TODO: set written_bytes
+            written_bytes = vfs_file_write(node, offset, n, mem);
-
-            vfs_file_write(node, offset, n, mem);
-            state->rax = STATUS_SUCCESS;
             break;
         }
     }
 
-    // TODO: return written_bytes to process
+    state->rax = written_bytes;
 }
 
 void syscall_handle_nx_fdelete(cpu_state_T* state) {