暂时提交（未测试代码

apps/filereader/main.c

@@ -5,47 +5,57 @@ static bool isprint(char c) {
   return c >= 0x20 && c <= 0x7e;
 }
 
+static void print_data(const byte *data, usize len) {
+  for (usize i = 0; i < len; i += 16) {
+    printf("\033[1;33m%08x\033[0m  ", i);
+    for (usize j = 0; j < 16; j++) {
+      if (i + j < len) {
+        printf("%02x ", data[i + j]);
+      } else {
+        printf("   ");
+      }
+    }
+    printf(" ");
+    for (usize j = 0; j < 16; j++) {
+      if (i + j >= len) break;
+      if (isprint(data[i + j]))
+        printf("\033[1;32m%c\033[0m", data[i + j]);
+      else
+        printf("\033[1;30m.\033[0m");
+    }
+    printf("\n");
+  }
+}
 int main(int argc, const char **argv) {
+
   if (argc != 2) {
     printf("Usage: %s filename\n", argv[0]);
     return 1;
   }
-  isize size = __syscall(SYSCALL_FILE_SIZE, argv[1]);
-  if (size < 0) {
-    printf("File not found: %s\n", argv[1]);
-    return 1;
-  }
-  byte *buf = (byte *)xmalloc(size);
-  if (__syscall(SYSCALL_LOAD_FILE, argv[1], buf, size) < 0) {
-    printf("Failed to load file: %s\n", argv[1]);
-    free(buf);
+  int fd = __syscall(SYSCALL_OPEN, argv[1], 0, 0);
+  if (fd < 0) {
+    printf("Failed to open file: %s\n", argv[1]);
     return 1;
   }
+  // isize size = __syscall(SYSCALL_FILE_SIZE, argv[1]);
+  // if (size < 0) {
+  //   printf("File not found: %s\n", argv[1]);
+  //   return 1;
+  // }
+
   printf("\033[1;35mHEX DUMP\033[0m  ");
   for (usize j = 0; j < 16; j++) {
     printf("\033[1;37m%02x\033[0m ", j);
   }
   printf(" \033[1;36mCHAR\033[0m\n");
-  for (usize i = 0; i < size; i += 16) {
-    printf("\033[1;33m%08x\033[0m  ", i);
-    for (usize j = 0; j < 16; j++) {
-      if (i + j < size) {
-        printf("%02x ", buf[i + j]);
-      } else {
-        printf("   ");
-      }
-    }
-    printf(" ");
-    for (usize j = 0; j < 16; j++) {
-      if (i + j >= size) break;
-      if (isprint(buf[i + j])) {
-        printf("\033[1;32m%c\033[0m", buf[i + j]);
-      } else {
-        printf("\033[1;30m.\033[0m");
-      }
-    }
-    printf("\n");
+
+  byte *buf = malloc(1024);
+  while (true) {
+    val len = __syscall(SYSCALL_READ,fd, buf, 1024);
+    if (len == 0) break;
+    print_data(buf, len);
   }
   free(buf);
+  __syscall(SYSCALL_CLOSE, fd);
   return 0;
 }

include/kernel/resman.h

@@ -10,8 +10,10 @@ typedef struct descriptor {
   vfs_node_t node;
   i32        refrence_cout;
 } *describtor_t;
-
-#define resman_free(man) free(((void *)(man)))
+typedef struct handle {
+  describtor_t fd;
+  isize        offset;
+} *handle_t;
 
 resman_t resman_alloc();
 void     resman_init(resman_t man);
@@ -20,5 +22,7 @@ int      resman_open(resman_t man, i32 working_dir, cstr path);
 int      resman_close(resman_t man, i32 id);
 resman_t resman_clone(resman_t man);
 void     resman_deinit(resman_t man);
+int      resman_set_offset(resman_t man, i32 id, isize offset);
 
+#define resman_free(man)          free(((void *)(man)))
 #define resman_open_root_dir(man) resman_open((man), 0, "/")

include/kernel/syscall.h

@@ -13,3 +13,5 @@ void   *syscall_mmap(void *start, u32 length);
 void    syscall_munmap(void *start, u32 length);
 ssize_t syscall_read(int fd, void *addr, size_t size);
 ssize_t syscall_write(int fd, const void *addr, size_t size);
+int     syscall_open(const char *path, int flags, int mode);
+int     syscall_close(int fd);

include/sys/plos-syscall.h

@@ -12,6 +12,8 @@ enum {
   SYSCALL_MUNMAP  = 7,
   SYSCALL_READ    = 8,
   SYSCALL_WRITE   = 9,
+  SYSCALL_OPEN    = 10,
+  SYSCALL_CLOSE   = 11,
   //% 以下是临时 syscall，编号从 128 开始，可能随时删除
   SYSCALL_VBE_SETMODE = 128,
   SYSCALL_VBE_FLIP    = 129,

src/fs/vfs.c

@@ -248,7 +248,9 @@ ssize_t vfs_write(vfs_node_t file, const void *addr, size_t offset, size_t size)
   assert(addr != null);
   do_update(file);
   if (file->type != file_block) return -1;
-  return callbackof(file, write)(file->handle, addr, offset, size);
+  ssize_t write_bytes = callbackof(file, write)(file->handle, addr, offset, size);
+  if (write_bytes > 0) { file->size = max(file->size, offset + write_bytes); }
+  return write_bytes;
 }
 
 int vfs_unmount(cstr path) {
@@ -277,8 +279,8 @@ int vfs_unmount(cstr path) {
 // 使用请记得free掉返回的buff
 char *vfs_get_fullpath(vfs_node_t node) {
   if (node == null) return null;
-  int inital = 16;
-  vfs_node_t *nodes = (vfs_node_t *)malloc(sizeof(vfs_node_t) * inital);
+  int         inital = 16;
+  vfs_node_t *nodes  = (vfs_node_t *)malloc(sizeof(vfs_node_t) * inital);
   int         count  = 0;
   for (vfs_node_t cur = node; cur; cur = cur->parent) {
     if (count >= inital) {

src/kernel/hal/resman.c

@@ -68,13 +68,23 @@ int resman_open(resman_t man, i32 working_dir, cstr path) {
     assert(dir, "open / failed");
     full_path = strdup(path);
   } else {
-    fd_dir = avltree_get(man->avltree, working_dir);
+    // 先取得工作目录的句柄
+    handle_t dir_hand = avltree_get(man->avltree, working_dir);
+    klogd("dir_hand is %p", dir_hand);
+    if (!dir_hand) return -1; // 无效的工作目录
+
+    // 然后取得工作目录的文件描述符
+    fd_dir = dir_hand->fd;
     klogd("fd_dir is %p", fd_dir);
     if (!fd_dir) return -1; // 无效的工作目录
+
+    // 然后取得工作目录的节点
     dir = fd_dir->node;
     if (dir->type != file_dir) return -1; // 工作目录不是一个目录
+
     full_path = vfs_get_fullpath(dir);
     full_path = (char *)realloc(full_path, strlen(full_path) + strlen(path) + 2);
+
     assert(full_path); // 这如果申请失败了，那么炸了算了
     if (full_path[strlen(full_path) - 1] != '/') strcat(full_path, "/");
     strcat(full_path, path);
@@ -87,23 +97,40 @@ int resman_open(resman_t man, i32 working_dir, cstr path) {
   klogd("we get the fd %p", fd);
   free(full_path);
 
-  int id = alloc_next_id(man);
-  avltree_insert(man->avltree, id, fd);
+  int      id     = alloc_next_id(man);
+  handle_t handle = malloc(sizeof(struct handle));
+  handle->fd      = fd;
+  handle->offset  = 0;
+  avltree_insert(man->avltree, id, handle);
   return id;
 
 err:
   free(full_path);
   return -1;
 }
 
+// @return 0: success, -1: failed
+int resman_set_offset(resman_t man, i32 id, isize offset) {
+  handle_t hand = avltree_get(man->avltree, id);
+  if (!hand) return -1; // 无效的文件描述符
+
+  if (hand->fd->node->type == file_dir || hand->fd->node->type == file_none)
+    return -1; // 不是一个文件或者没有被vfs正常打开
+
+  if (hand->offset + offset > hand->fd->node->size) return -1; // 超出文件大小
+
+  hand->offset = offset;
+  return 0;
+}
+
 // @return 0: success, -1: failed
 int resman_close(resman_t man, i32 id) {
-  describtor_t fd = avltree_get(man->avltree, id);
-  if (!fd) return -1; // 无效的文件描述符
+  handle_t hand = avltree_get(man->avltree, id);
+  if (!hand) return -1; // 无效的文件描述符
 
-  int status = descriptor_close(fd);
+  int status = descriptor_close(hand->fd);
   if (status == -1) return -1;
-
+  free(hand);
   avltree_delete(man->avltree, id);
   man->next_id = id;
   return 0;
@@ -125,7 +152,9 @@ resman_t resman_clone(resman_t man) {
   return new_resman;
 }
 static void close_file(void *p) {
-  descriptor_close(p);
+  handle_t hand = p;
+  descriptor_close(hand->fd);
+  free(hand);
 }
 void resman_deinit(resman_t man) {
   avltree_free_with(man->avltree, close_file);

src/kernel/syscall/read-write.c

@@ -7,21 +7,67 @@
 //   open,
 //   close,
 // };
+
+//TODO: The parameter mode does not support yet
 int syscall_open(const char *path, int flags, int mode) {
   if (!check_string_permission(path)) task_abort();
-  return resman_open(current_task->resman, current_task->working_dir, path);
+  int fd = resman_open(current_task->resman, current_task->working_dir, path);
+  if (fd < 0) return -1;
+
+  handle_t file = avltree_get(current_task->resman->avltree, fd);
+
+  // 检查文件句柄是否合法
+  if (file == null) return -1;
+  if (file->fd == null) return -1;
+  if (file->fd->node == null) return -1;
+  if (file->fd->node->type == file_dir) {
+    resman_close(current_task->resman, fd);
+    return -1;
+  }
+
+  return fd;
 }
 
 isize syscall_read(int fd, void *addr, usize size) {
   if (fd < 0) return -1;
   if (addr == null) return -1;
-  describtor_t file = avltree_get(current_task->resman->avltree, fd);
+
+  handle_t file = avltree_get(current_task->resman->avltree, fd);
+
+  // 检查文件句柄是否合法
   if (file == null) return -1;
-  return vfs_read(file->node, addr, 0, size);
+  if (file->fd == null) return -1;
+  if (file->fd->node == null) return -1;
+  if (file->fd->node->type == file_dir) return -1;
+
+  isize read_bytes = vfs_read(file->fd->node, addr, file->offset, size);
+
+  // 这里offset必不可能超过文件大小
+  file->offset += read_bytes;
+
+  return read_bytes;
 }
 
 isize syscall_write(int fd, const void *addr, usize size) {
   if (fd < 0) return -1;
   if (addr == null) return -1;
-  return 0;
+
+  handle_t file = avltree_get(current_task->resman->avltree, fd);
+
+  // 检查文件句柄是否合法
+  if (file == null) return -1;
+  if (file->fd == null) return -1;
+  if (file->fd->node == null) return -1;
+  if (file->fd->node->type == file_dir) return -1;
+
+  isize write_bytes = vfs_write(file->fd->node, addr, file->offset, size);
+
+  file->offset += write_bytes;
+
+  return write_bytes;
+}
+
+int syscall_close(int fd) {
+  if (fd < 0) return -1;
+  return resman_close(current_task->resman, fd);
 }

src/kernel/syscall/syscall.c

@@ -84,8 +84,8 @@ static void *const sycall_handlers[MAX_SYSCALLS] = {
     [SYSCALL_MUNMAP]  = &syscall_munmap,
     [SYSCALL_READ]    = &syscall_read,
     [SYSCALL_WRITE]   = &syscall_write,
-    // [SYSCALL_OPEN] = syscall_open,
-    // [SYSCALL_CLOSE] = syscall_close,
+    [SYSCALL_OPEN]    = &syscall_open,
+    [SYSCALL_CLOSE]   = &syscall_close,
     // [SYSCALL_WAITPID] = syscall_waitpid,
     // [SYSCALL_EXECVE] = syscall_execve,
     // [SYSCALL_CHDIR] = syscall_chdir,