builtin basic function

Author: chengscott

builtin.c

@@ -1,11 +1,64 @@
+#include <dirent.h>
+#include <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/stat.h>
+#include <sys/time.h>
 #include <sys/types.h>
+#include <time.h>
 #include <unistd.h>
+#include <utime.h>
 #define N 1024
 
+const char *help_string[] = {
+    "cat {file}:              Display content of {file}.",
+    "cd {dir}:                Switch current working directory to {dir}.",
+    "chmod {mode} {file/dir}: Change the mode (permission) of a file or "
+    "directory.",
+    "                         {mode} is an octal number.",
+    "                         Please do not follow symbolc links.",
+    "echo {str} [filename]:   Display {str}. If [filename] is given,",
+    "                         open [filename] and append {str} to the file.",
+    "exit:                    Leave the shell.",
+    "find [dir]:              List files/dirs in the current working "
+    "directory",
+    "                         or [dir] if it is given.",
+    "                         Minimum outputs contatin file type, size, and "
+    "name.",
+    "help:                    Display help message.",
+    "id:                      Show current euid and egid.",
+    "mkdir {dir}:             Create a new directory {dir}.",
+    "pwd:                     Print the current working directory.",
+    "rm {file}:               Remove a file.",
+    "rmdir {dir}:             Remove an empty directory.",
+    "stat {file/dir}:         Display detailed information of the given "
+    "file/dir.",
+    "touch {file}:            Create {file} if it does not exist,",
+    "                         or update its access and modification "
+    "timestamp.",
+    "umask {mode}:            Change the umask of the current session."};
+
+const char *get_file_type(int mode) {
+  const char *file_type[] = {"named pipe (fifo)",
+                             "character special file",
+                             "directory",
+                             "block special file",
+                             "regular file",
+                             "symbolic link",
+                             "socket",
+                             "unknown"};
+  const int file_mask[] = {S_IFIFO, S_IFCHR, S_IFDIR, S_IFBLK,
+                           S_IFREG, S_IFLNK, S_IFSOCK};
+
+  for (size_t i = 0; i < 7; ++i) {
+    if (mode == file_mask[i]) {
+      return file_type[i];
+    }
+  }
+  return file_type[7];
+}
+
 int builtin_cat(char *line) {
   char arg[N], extra[N];
   if (sscanf(line, "%*s %s %s", arg, extra) != 1) return -1;
@@ -64,40 +117,31 @@ int builtin_exit(char *line) {
   return 1;
 }
 
-int builtin_find(char *cmd) { return 0; }
+int builtin_find(char *line) {
+  char arg[N], extra[N];
+  int argc;
+  if ((argc = sscanf(line, "%*s %s %s", arg, extra)) > 1) return -1;
+
+  DIR *dir = opendir(argc == 1 ? arg : ".");
+  struct dirent *dp;
+  struct stat info;
+  int ret;
+  while ((dp = readdir(dir)) != NULL) {
+    printf("%-20s", dp->d_name);
+    ret = stat(dp->d_name, &info);
+    // if (ret == -1) { ; continue; }
+    printf("\t%-20s\t%-5ld\n", get_file_type(info.st_mode & S_IFMT),
+           info.st_size);
+  }
+  closedir(dir);
+  return 0;
+}
 
 int builtin_help(char *line) {
   char extra[N];
   if (sscanf(line, "%*s %s", extra) > 0) return -1;
 
-  const char *help_string[] = {
-      "cat {file}:              Display content of {file}.",
-      "cd {dir}:                Switch current working directory to {dir}.",
-      "chmod {mode} {file/dir}: Change the mode (permission) of a file or "
-      "directory.",
-      "                         {mode} is an octal number.",
-      "                         Please do not follow symbolc links.",
-      "echo {str} [filename]:   Display {str}. If [filename] is given,",
-      "                         open [filename] and append {str} to the file.",
-      "exit:                    Leave the shell.",
-      "find [dir]:              List files/dirs in the current working "
-      "directory",
-      "                         or [dir] if it is given.",
-      "                         Minimum outputs contatin file type, size, and "
-      "name.",
-      "help:                    Display help message.",
-      "id:                      Show current euid and egid.",
-      "mkdir {dir}:             Create a new directory {dir}.",
-      "pwd:                     Print the current working directory.",
-      "rm {file}:               Remove a file.",
-      "rmdir {dir}:             Remove an empty directory.",
-      "stat {file/dir}:         Display detailed information of the given "
-      "file/dir.",
-      "touch {file}:            Create {file} if it does not exist,",
-      "                         or update its access and modification "
-      "timestamp.",
-      "umask {mode}:            Change the umask of the current session."};
-  size_t len = sizeof(help_string) / sizeof(char *);
+  const size_t len = sizeof(help_string) / sizeof(char *);
   for (size_t i = 0; i < len; ++i) printf("%s\n", help_string[i]);
   return 0;
 }
@@ -148,16 +192,38 @@ int builtin_rmdir(char *line) {
   return 0;
 }
 
-int builtin_stat(char *cmd) { return 0; }
+int builtin_stat(char *line) {
+  char arg[N], extra[N];
+  if (sscanf(line, "%*s %s %s", arg, extra) != 1) return -1;
+
+  struct stat info;
+  int ret = stat(arg, &info);
+  // if (ret == -1)
+  printf(
+      "\
+  File: %s\n\
+  Size: %lld               Blocks: %lld          IO Block: %ld   %s\n\
+Device: %s      Inode: %ld   Links: %d\n\
+Access: (%lo)  Uid: (%ld)   Gid: (%ld)\n\
+Access: %s\
+Modify: %s\
+Change: %s",
+      arg, info.st_size, info.st_blocks, info.st_blksize,
+      get_file_type(info.st_mode & S_IFMT),
+      "",  // info.st_dev,
+      info.st_ino, info.st_nlink, info.st_mode & 0777, info.st_uid, info.st_gid,
+      ctime(&info.st_atime), ctime(&info.st_mtime), ctime(&info.st_ctime));
+  return 0;
+}
 
 int builtin_touch(char *line) {
   char arg[N], extra[N];
   if (sscanf(line, "%*s %s %s", arg, extra) != 1) return -1;
 
-  FILE *file;
-  // if (access(arg, F_OK) != -1)
-  file = fopen(arg, "a+");
-  fclose(file);
+  int fd = open(arg, O_WRONLY | O_CREAT | O_NOCTTY | O_NONBLOCK, 0666);
+  // if (fd < 0)
+  int rc = utimensat(AT_FDCWD, arg, NULL, 0);
+  // if (rc)
   return 0;
 }