feature (syscalls): implemented basic file syscalls (nx_fopen, nx_fclose, nx_fread, nx_fwrite)

kernel/inc/proc/process.h

@@ -6,6 +6,7 @@
 #include "utils/stdtypes.h"
 #include "utils/string.h"
 #include "utils/bitmap.h"
+#include "proc/file_descriptor.h"
 #include "mm/page_map.h"
 #include "drivers/elf/elf.h"
 
@@ -28,6 +29,7 @@ struct process_T {
 
     page_map_T*                 page_map;
     elf_executable_T*           executable;
+    file_descriptor_array_T*    fd_array;
 
     uint32_t                num_threads;
     void*                       threads;

kernel/src/kmain.c

@@ -57,9 +57,12 @@ void kmain(boot_info_T boot_info) {
 
     log(LOG_INFO, "!=====[ Kernel Initialized ]=====!\n");
 
-    status_E status = syscall_perform(SYSCALL_FILES_OPEN, (uint64_t)"/initrd/test.txt", 0, 0, 0);
-
-    log(LOG_DEBUG, "syscall returned status: %s", g_status_code_strings[status]);
+    file_descriptor_t fd;
+    syscall_perform(SYSCALL_FILES_OPEN, (uint64_t)"/initrd/test.txt", &fd, 0, 0);
+    syscall_perform(SYSCALL_FILES_WRITE, fd, 0, "Write test", 10);
+    char buffer[64];
+    syscall_perform(SYSCALL_FILES_READ, fd, 0, (uint64_t)buffer, 64);
+    memory_hexdump(buffer, 64);
 
 //    vfs_node_T* node = vfs_resolve_path(&g_root_fs, "/initrd/test.elf");
 //    void* buffer = memory_allocate(node->size);

kernel/src/platform/syscall.c

@@ -7,8 +7,8 @@
 #include "drivers/fs/vfs.h"
 
 void syscall_handle_nx_fopen(cpu_state_T* state) {
-    // read arguments
     uint64_t arg1 = state->rdi;
+    uint64_t arg2 = state->rsi;
 
     vfs_node_T *node = vfs_resolve_path(&g_root_fs, (string_t) arg1);
     if (node == NULL) {
@@ -16,7 +16,41 @@ void syscall_handle_nx_fopen(cpu_state_T* state) {
         return;
     }
 
-    log(LOG_DEBUG, "resolved file '%s' -> 0x%x", arg1, node);
+    *(file_descriptor_t*)(arg2) = file_descriptor_request(scheduler_get_current_process()->fd_array, node);
+}
+
+void syscall_handle_nx_fclose(cpu_state_T* state) {
+    uint64_t arg1 = state->rdi;
+
+    file_descriptor_free(scheduler_get_current_process()->fd_array, (file_descriptor_t)arg1);
+
+    state->rax = STATUS_SUCCESS;
+}
+
+void syscall_handle_nx_fread(cpu_state_T* state) {
+    uint64_t arg1 = state->rdi;
+    uint64_t arg2 = state->rsi;
+    uint64_t arg3 = state->rdx;
+    uint64_t arg4 = state->rcx;
+
+    vfs_node_T* node = file_descriptor_resolve(scheduler_get_current_process()->fd_array, (file_descriptor_t)arg1);
+
+    vfs_file_read(node, arg2, arg4, (uint8_t*)arg3);
+
+    state->rax = STATUS_SUCCESS;
+}
+
+void syscall_handle_nx_fwrite(cpu_state_T* state) {
+    uint64_t arg1 = state->rdi;
+    uint64_t arg2 = state->rsi;
+    uint64_t arg3 = state->rdx;
+    uint64_t arg4 = state->rcx;
+
+    vfs_node_T* node = file_descriptor_resolve(scheduler_get_current_process()->fd_array, (file_descriptor_t)arg1);
+
+    vfs_file_write(node, arg2, arg4, (uint8_t*)arg3);
+
+    state->rax = STATUS_SUCCESS;
 }
 
 
@@ -35,6 +69,18 @@ cpu_state_T* syscall_handle(cpu_state_T* state) {
                     syscall_handle_nx_fopen(state);
                     break;
                 }
+                case SYSCALL_FILES_CLOSE: {
+                    syscall_handle_nx_fclose(state);
+                    break;
+                }
+                case SYSCALL_FILES_READ: {
+                    syscall_handle_nx_fread(state);
+                    break;
+                }
+                case SYSCALL_FILES_WRITE: {
+                    syscall_handle_nx_fwrite(state);
+                    break;
+                }
             }
             break;
         }
@@ -77,6 +123,7 @@ cpu_state_T* syscall_handle(cpu_state_T* state) {
                     break;
                 }
             }
+            break;
         }
 
         default: {

kernel/src/proc/process.c

@@ -12,6 +12,7 @@ void process_kernel_spawn(elf_executable_T* executable) {
     process->threads     = NULL;
     process->parent      = NULL;
     process->executable  = executable;
+    process->fd_array    = file_descriptor_array_alloc();
 
     memory_copy("kernel", process->name, 7);
 
@@ -29,6 +30,7 @@ pid_t process_spawn(pid_t parent, string_t name, elf_executable_T* executable, v
     process->thread_ids  = bitmap_init(MAX_THREADS_PER_PROCESS);
     process->parent      = scheduler_get_process(parent);
     process->executable  = executable;
+    process->fd_array    = file_descriptor_array_alloc();
 
     memory_copy(name, process->name, MIN(string_length(name), 127));
 
@@ -61,6 +63,7 @@ void process_kill_pid(pid_t pid) {
 void process_kill(process_T* process) {
     scheduler_kill_process(process);
 
+    file_descriptor_array_destruct(process->fd_array);
     elf_executable_destruct(process->executable);
     page_map_destruct(process->page_map);
     bitmap_destruct(&process->thread_ids);