fix fs_read and cat

lab5/user/lab5/apps/init.c

@@ -7,6 +7,7 @@
 #include <ipc.h>
 #include <string.h>
 #include <proc.h>
+#include "malloc.h"
 
 #define SERVER_READY_FLAG(vaddr) (*(int *)(vaddr))
 #define SERVER_EXIT_FLAG(vaddr)  (*(int *)((u64)vaddr+ 4))
@@ -14,6 +15,7 @@
 extern ipc_struct_t *tmpfs_ipc_struct;
 static ipc_struct_t ipc_struct;
 static int tmpfs_scan_pmo_cap;
+static int tmpfs_read_pmo_cap;
 
 /* fs_server_cap in current process; can be copied to others */
 int fs_server_cap;
@@ -83,21 +85,51 @@ int do_top()
 	return 0;
 }
 
+/**
+ * 转为绝对路径
+ */
+void path_to_absolute(char *path) {
+    char pathbuf[BUFLEN];
+    strcpy(pathbuf + 1, path);
+    pathbuf[0] = '/';
+    strcpy(path, pathbuf);
+}
+
+/**
+ * 路径连接
+ */
+void path_append(char *path, char *sub) {
+    size_t path_len = strlen(path);
+    // path 末尾应该有 '/'
+    if (path[path_len - 1] == '/') {
+        path += path_len;
+    } else {
+        path[path_len] = '/';
+        path += path_len + 1;
+    }
+    // sub 之前没有 '/'
+    while (*sub == '/') sub++;
+    // 连接路径
+    strcpy(path, sub);
+}
+
+/**
+ * 扫描目录
+ */
 int fs_scan(char *path)
 {
-	// TODO: your code here
     int count = 4096/2;
-    char str[256];
     struct fs_request fr;
     int ret;
 
+    // 拼接请求
     fr.req = FS_REQ_SCAN;
     fr.buff = (char *) TMPFS_SCAN_BUF_VADDR;
-    strcpy(fr.path + 1, path);
-    fr.path[0] = '/';
+    strcpy(fr.path, path);
     fr.offset = 0;
     fr.count = count;
 
+    // 发送
     printf("Send ls: %s\n", path);
     ipc_msg_t *ipc_msg = ipc_create_msg(tmpfs_ipc_struct, sizeof(fr), 1);
     ipc_set_msg_data(ipc_msg, (void *)&fr, 0, sizeof(fr));
@@ -108,16 +140,98 @@ int fs_scan(char *path)
     return ret;
 }
 
+/**
+ * 获得文件大小
+ */
+int fs_get_size(char *path)
+{
+    struct fs_request fr;
+    int ret;
+
+    // 拼接请求
+    fr.req = FS_REQ_GET_SIZE;
+    strcpy(fr.path, path);
+
+    // 发送
+    ipc_msg_t *ipc_msg = ipc_create_msg(tmpfs_ipc_struct, sizeof(fr), 1);
+    ipc_set_msg_data(ipc_msg, (void *)&fr, 0, sizeof(fr));
+    ipc_set_msg_cap(ipc_msg, 0, tmpfs_scan_pmo_cap);
+    ret = ipc_call(tmpfs_ipc_struct, ipc_msg);
+    ipc_destroy_msg(ipc_msg);
+    return ret;
+}
+
+int fs_read(char *path, off_t offset, ssize_t count) {
+    struct fs_request fr;
+    int ret;
+
+    fail_cond(count > PAGE_SIZE,
+              "read size should smaller than %d, now %d", PAGE_SIZE, count);
+
+    // 拼接请求
+    fr.req = FS_REQ_READ;
+    fr.buff = (char *) TMPFS_READ_BUF_VADDR;
+    strcpy(fr.path, path);
+    fr.offset = offset;
+    fr.count = count;
+
+    // 发送
+    ipc_msg_t *ipc_msg = ipc_create_msg(tmpfs_ipc_struct, sizeof(fr), 1);
+    ipc_set_msg_data(ipc_msg, (void *)&fr, 0, sizeof(fr));
+    ipc_set_msg_cap(ipc_msg, 0, tmpfs_read_pmo_cap);
+    ret = ipc_call(tmpfs_ipc_struct, ipc_msg);
+    ipc_destroy_msg(ipc_msg);
+    return ret;
+}
+
+/**
+ * 读入文件并返回长度
+ */
+int fs_read_all(char *path, void **ret_buf)
+{
+    // 获得文件长度
+    int size = fs_get_size(path);
+    if (size < 0) {
+        return size;
+    }
+
+    // 申请缓冲
+    unsigned char *buf = malloc(size);
+    if (!buf) {
+        return -1;
+    }
+    *ret_buf = buf;
+
+    // 读入文件
+    // FIXME: 读取 1 页以上会遇到 warning: vmr overlap
+    int pos = 0;
+    while (size - pos > 0) {
+        int cur = fs_read(path, pos, PAGE_SIZE - 1);
+        if (cur < 0) {
+            return cur;
+        }
+        memcpy(buf, (const void *) TMPFS_READ_BUF_VADDR, cur);
+        pos += cur;
+        buf += cur;
+    }
+
+    return size;
+}
+
 int do_ls(char *cmdline)
 {
 	char pathbuf[BUFLEN];
+    char fpathbuf[BUFLEN];
 	int ret;
 
 	pathbuf[0] = '\0';
 	cmdline += 2;
 	while (*cmdline == ' ')
 		cmdline++;
-	strcat(pathbuf, cmdline);
+	// 路径格式化
+    strcat(pathbuf, cmdline);
+    path_to_absolute(pathbuf);
+    // 请求 fs
     ret = fs_scan(pathbuf);
     if (ret >= 0) {
         char *print_ptr;
@@ -126,7 +240,17 @@ int do_ls(char *cmdline)
 
         for (int i = 0; i < ret; i++) {
             dirat = (struct dirent *) print_ptr;
-            printf(" %s\n", dirat->d_name);
+            // 文件类型
+            char type = 'f';
+            if (dirat->d_type == 2) {
+                type = 'd'; // 目录
+            }
+            // 文件大小
+            strcpy(fpathbuf, pathbuf);
+            path_append(fpathbuf, dirat->d_name);
+            int size = fs_get_size(fpathbuf);
+            // 输出
+            printf("%c %10d %s\n", type, size, dirat->d_name);
             print_ptr += dirat->d_reclen;
         }
     } else {
@@ -143,9 +267,22 @@ int do_cat(char *cmdline)
 	cmdline += 3;
 	while (*cmdline == ' ')
 		cmdline++;
-	strcat(pathbuf, cmdline);
-	// fs_scan(pathbuf);
-	printf("apple banana This is a test file.\n");
+    // 路径格式化
+    strcat(pathbuf, cmdline);
+    path_to_absolute(pathbuf);
+	// 读入文件
+    char *buf;
+    int ret = fs_read_all(pathbuf, (void **) &buf);
+    if (ret < 0) {
+        printf("cannot cat file, code %d\n", ret);
+        return ret;
+    }
+    // 打印
+    for (int i = 0; i < ret; i++) {
+        usys_putc(buf[i]);
+    }
+    free(buf);
+
 	return 0;
 }
 
@@ -296,5 +433,15 @@ void boot_fs(void)
 			   TMPFS_SCAN_BUF_VADDR, VM_READ | VM_WRITE);
 	fail_cond(ret < 0, "usys_map_pmo ret %d\n", ret);
 
+    // 创建读文件 pmo
+    tmpfs_read_pmo_cap = usys_create_pmo(PAGE_SIZE, PMO_DATA);
+    fail_cond(tmpfs_read_pmo_cap < 0, "usys create_ret ret %d\n",
+              tmpfs_read_pmo_cap);
+
+    ret = usys_map_pmo(SELF_CAP,
+                       tmpfs_read_pmo_cap,
+                       TMPFS_READ_BUF_VADDR, VM_READ | VM_WRITE);
+    fail_cond(ret < 0, "usys_map_pmo ret %d\n", ret);
+
 	printf("fs is UP.\n");
 }