changeset 912:f4f5132d5ac7

Stat cleanup. From the mailing list: Ok, first thing: clean up the help text. I realize what's there is copied verbatim from the man page, but that man page sucks. ("modification time" vs "change time"?) Took a bit of finagling to fit it in 80x24, but just made it. GLOBALS() indent was still tab, change to two spaces. And I tend to put a blank line between options lib/args.c automatically fills out and normal globals. We never do anything with date_stat_format() but immediately print it, might as well make the function do it. The types[] array in do_stat() is a rough edge. Hmmm... there's no else case that sets the type in case it was unknown (such as 0). In theory, this never happens. In practice it means I can cheat slightly, given this observation: $ find linux -name stat.h | xargs grep 'S_IF[A-Z]*[ \t]' linux/include/uapi/linux/stat.h:#define S_IFMT 00170000 linux/include/uapi/linux/stat.h:#define S_IFSOCK 0140000 linux/include/uapi/linux/stat.h:#define S_IFLNK 0120000 linux/include/uapi/linux/stat.h:#define S_IFREG 0100000 linux/include/uapi/linux/stat.h:#define S_IFBLK 0060000 linux/include/uapi/linux/stat.h:#define S_IFDIR 0040000 linux/include/uapi/linux/stat.h:#define S_IFCHR 0020000 linux/include/uapi/linux/stat.h:#define S_IFIFO 0010000 I.E. the only place the I_IFBLAH constants occur a stat.h header in current linux code is in the generic stuff, it doesn't vary per target. (The access permission bits are actually subtly standardized in posix due to the command line arguments to chmod, although I'm sure cygwin finds a way to break. But the type fields, not so much. But linux has to be binary compatible with itself foreverish, and that's all I really care about.) So, we have ALMOST have this going by twos, except there's no 8 and there is a 1. so let's make the 1 the default, feed a blank string into the 8... No, duh: octal. So it's actually 2, 4, 6, 8, 10, 12. So make the loop look like: filetype = statf->st_mode & S_IFMT; TT.ftname = types; for (i = 1; filetype != (i*8192) && i < 7; i++) TT.ftname += strlen(TT.ftname)+1; Yes that's linux-specific, and I think I'm ok with that. Printing all zeroes and pretending that's nanosecond resolution... either support it or don't. Let's see, supporting it is stat->st_atim.tv_nsec and similar... no mention of nanoseconds in strftime() (et tu, posix2008?) so pass it as a second argument and append it by hand... (Need to test that against musl...) When we hit an unknown type in print_it() we print the literal character, which is right for %% but what about an unknown option? $ stat -c %q / ? Eh, I guess that's a "don't care". It didn't die with an error, that's the important thing. I have a horrible idea for compressing the switch/case blocks, but should probably check this in and get some sleep for right now...
author Rob Landley <>
date Tue, 28 May 2013 00:28:45 -0500
parents accabaaac666
children 7fed25030389
files toys/pending/stat.c
diffstat 1 files changed, 46 insertions(+), 72 deletions(-) [+]
line wrap: on
line diff
--- a/toys/pending/stat.c	Sun May 26 09:48:13 2013 +0200
+++ b/toys/pending/stat.c	Tue May 28 00:28:45 2013 -0500
@@ -10,75 +10,55 @@
     usage: stat [-f] [-c FORMAT] FILE...
-    display file or file system status
+    Display status of files or filesystems.
-    -f display file system status instead of file status
-    -c use the specified FORMAT instead of the default;
-       output a newline after each use of FORMAT
+    -f display filesystem status instead of file status
+    -c Output specified FORMAT string instead of default
-    The valid format sequences for files:
-    %a     Access rights in octal
-    %A     Access rights in human readable form
-    %b     Number of blocks allocated
-    %B     The size in bytes of each block
-    %d     Device number in decimal
-    %D     Device number in hex
-    %f     Raw mode in hex
-    %F     File type
-    %g     Group ID of owner
-    %G     Group name of owner
-    %h     Number of hard links
-    %i     Inode number
-    %n     File name
-    %N     Quoted file name with dereference if symbolic link
-    %o     I/O block size
-    %s     Total size, in bytes
-    %u     User ID of owner
-    %U     User name of owner
-    %x     Time of last access
-    %X     Time of last access as seconds since Epoch
-    %y     Time of last modification
-    %Y     Time of last modification as seconds since Epoch
-    %z     Time of last change
-    %Z     Time of last change as seconds since Epoch
+    The valid format escape sequences for files:
+    %a  Access bits (octal) |%A  Access bits (flags)|%b  Blocks allocated
+    %B  Bytes per block     |%d  Device ID (dec)    |%D  Device ID (hex)
+    %f  All mode bits (hex) |%F  File type          |%g  Group ID
+    %G  Group name          |%h  Hard links         |%i  Inode
+    %n  Filename            |%N  Long filename      |%o  I/O block size
+    %s  Size (bytes)        |%u  User ID            |%U  User name
+    %x  Access time         |%X  Access unix time   |%y  File write time
+    %Y  File write unix time|%z  Dir change time    |%Z  Dir change unix time
-    The valid format sequences for file systems:
-    %a     Available blocks for unpriviledges user
-    %b     Total number of blocks
-    %c     Total number of inodes
-    %d     Number of free inodes
-    %f     Number of free blocks
-    %i     File system ID
-    %l     Maximum length of file names
-    %n     File name
-    %s     Fragment size
-    %S     Optimal transfer block size
-    %t     File system type
+    The valid format escape sequences for filesystems:
+    %a  Available blocks    |%b  Total blocks       |%c  Total inodes
+    %d  Free inodes         |%f  Free blocks        |%i  File system ID
+    %l  Max filename length |%n  File name          |%s  Fragment size
+    %S  Best transfer size  |%t  File system type
 #define FOR_stat
 #include "toys.h"
-	char *fmt;
-	void *stat;
-	char *file_type;
-	struct passwd *user_name;
-	struct group *group_name;
-	char access_str[11];
+  char *fmt;
+  void *stat;
+  struct passwd *user_name;
+  struct group *group_name;
+  char *ftname, access_str[11];
-static char * date_stat_format(time_t time)
+static void date_stat_format(time_t time, int nano)
   static char buf[36];
+  int len;
-  strftime(buf, sizeof(buf), "%Y-%m-%d %H:%M:%S.000000000", localtime(&time));
-  return buf;
+  len = strftime(buf, sizeof(buf), "%Y-%m-%d %H:%M:%S.", localtime(&time));
+  sprintf(buf+len, "%09d", nano);
+  xprintf("%s", buf);
-static int print_stat(char type) {
+static int print_stat(char type)
   struct stat *stat = (struct stat*)TT.stat;
   switch (type) {
     case 'a':
       xprintf("%04lo", stat->st_mode & ~S_IFMT);
@@ -102,7 +82,7 @@
       xprintf("%lx", stat->st_mode);
     case 'F':
-      xprintf("%s", TT.file_type);
+      xprintf("%s", TT.ftname);
     case 'g':
       xprintf("%lu", stat->st_gid);
@@ -132,19 +112,19 @@
       xprintf("%8s", TT.user_name->pw_name);
     case 'x':
-      xprintf("%s", date_stat_format(stat->st_atime));
+      date_stat_format(stat->st_atime, stat->st_atim.tv_nsec);
     case 'X':
       xprintf("%llu", stat->st_atime);
     case 'y':
-      xprintf("%s", date_stat_format(stat->st_mtime));
+      date_stat_format(stat->st_mtime, stat->st_mtim.tv_nsec);
     case 'Y':
       xprintf("%llu", stat->st_mtime);
     case 'z':
-      xprintf("%s", date_stat_format(stat->st_ctime));
+      date_stat_format(stat->st_ctime, stat->st_ctim.tv_nsec);
     case 'Z':
       xprintf("%llu", stat->st_ctime);
@@ -157,6 +137,7 @@
 static int print_statfs(char type) {
   struct statfs *statfs = (struct statfs*)TT.stat;
   switch (type) {
     case 'a':
       xprintf("%lu", statfs->f_bavail);
@@ -197,32 +178,25 @@
 static int do_stat(char *path)
   struct stat *statf = (struct stat*)TT.stat;
-  size_t i;
-  struct {
-    mode_t mode;
-    char *str;
-  } types[] = {
-    {S_IFDIR, "directory"},
-    {S_IFCHR, "character device"},
-    {S_IFBLK, "block device"},
-    {S_IFREG, "regular file"},
-    {S_IFIFO, "FIFO (named pipe)"},
-    {S_IFLNK, "symbolic link"},
-    {S_IFSOCK, "socket"}
-  };
+  char *types = "character device\0directory\0block device\0" \
+               "regular file\0symbolic link\0socket\0FIFO (named pipe)";
+  int i, filetype;
   if (stat(path, statf) < 0) return 1;
-  for (i = 0; i < sizeof(types)/sizeof(*types); i++)
-    if ((statf->st_mode & S_IFMT) == types[i].mode) TT.file_type = types[i].str;
-  if (!statf->st_size && (statf->st_mode & S_IFMT) == S_IFREG)
-    TT.file_type = "regular empty file";
+  filetype = statf->st_mode & S_IFMT;
+  TT.ftname = types;
+  for (i = 1; filetype != (i*8192) && i < 7; i++)
+    TT.ftname += strlen(TT.ftname)+1;
+  if (!statf->st_size && filetype == S_IFREG)
+    TT.ftname = "regular empty file";
   // check user and group name
   TT.user_name = getpwuid(statf->st_uid);
   TT.group_name = getgrgid(statf->st_gid);
   // function to get access in human readable format
   format_mode(&TT.access_str, statf->st_mode);
   return 0;