hush/coreutils/du.c
Denys Vlasenko 393c395ca5 du: document incompatibility with standard tool
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2012-12-14 17:14:11 +01:00

273 lines
7.3 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini du implementation for busybox
*
* Copyright (C) 1999,2000,2001 by Lineo, inc. and John Beppu
* Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org>
* Copyright (C) 2002 Edward Betts <edward@debian.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
/* BB_AUDIT SUSv3 compliant (unless default blocksize set to 1k) */
/* http://www.opengroup.org/onlinepubs/007904975/utilities/du.html */
/* Mar 16, 2003 Manuel Novoa III (mjn3@codepoet.org)
*
* Mostly rewritten for SUSv3 compliance and to fix bugs/defects.
* 1) Added support for SUSv3 -a, -H, -L, gnu -c, and (busybox) -d options.
* The -d option allows setting of max depth (similar to gnu --max-depth).
* 2) Fixed incorrect size calculations for links and directories, especially
* when errors occurred. Calculates sizes should now match gnu du output.
* 3) Added error checking of output.
* 4) Fixed busybox bug #1284 involving long overflow with human_readable.
*/
//usage:#define du_trivial_usage
//usage: "[-aHLdclsx" IF_FEATURE_HUMAN_READABLE("hm") "k] [FILE]..."
//usage:#define du_full_usage "\n\n"
//usage: "Summarize disk space used for each FILE and/or directory\n"
//usage: "\n -a Show file sizes too"
//usage: "\n -L Follow all symlinks"
//usage: "\n -H Follow symlinks on command line"
//usage: "\n -d N Limit output to directories (and files with -a) of depth < N"
//usage: "\n -c Show grand total"
//usage: "\n -l Count sizes many times if hard linked"
//usage: "\n -s Display only a total for each argument"
//usage: "\n -x Skip directories on different filesystems"
//usage: IF_FEATURE_HUMAN_READABLE(
//usage: "\n -h Sizes in human readable format (e.g., 1K 243M 2G)"
//usage: "\n -m Sizes in megabytes"
//usage: )
//usage: "\n -k Sizes in kilobytes" IF_FEATURE_DU_DEFAULT_BLOCKSIZE_1K(" (default)")
//usage: IF_NOT_FEATURE_DU_DEFAULT_BLOCKSIZE_1K(
//usage: "\n Default unit is 512 bytes"
//usage: )
//usage:
//usage:#define du_example_usage
//usage: "$ du\n"
//usage: "16 ./CVS\n"
//usage: "12 ./kernel-patches/CVS\n"
//usage: "80 ./kernel-patches\n"
//usage: "12 ./tests/CVS\n"
//usage: "36 ./tests\n"
//usage: "12 ./scripts/CVS\n"
//usage: "16 ./scripts\n"
//usage: "12 ./docs/CVS\n"
//usage: "104 ./docs\n"
//usage: "2417 .\n"
#include "libbb.h"
enum {
OPT_a_files_too = (1 << 0),
OPT_H_follow_links = (1 << 1),
OPT_k_kbytes = (1 << 2),
OPT_L_follow_links = (1 << 3),
OPT_s_total_norecurse = (1 << 4),
OPT_x_one_FS = (1 << 5),
OPT_d_maxdepth = (1 << 6),
OPT_l_hardlinks = (1 << 7),
OPT_c_total = (1 << 8),
OPT_h_for_humans = (1 << 9),
OPT_m_mbytes = (1 << 10),
};
struct globals {
#if ENABLE_FEATURE_HUMAN_READABLE
unsigned long disp_hr;
#else
unsigned disp_k;
#endif
int max_print_depth;
bool status;
int slink_depth;
int du_depth;
dev_t dir_dev;
} FIX_ALIASING;
#define G (*(struct globals*)&bb_common_bufsiz1)
#define INIT_G() do { } while (0)
/* FIXME? coreutils' du rounds sizes up:
* for example, 1025k file is shown as "2" by du -m.
* We round to nearest.
*/
static void print(unsigned long long size, const char *filename)
{
/* TODO - May not want to defer error checking here. */
#if ENABLE_FEATURE_HUMAN_READABLE
printf("%s\t%s\n",
/* size x 512 / G.disp_hr, show one fractional,
* use suffixes if G.disp_hr == 0 */
make_human_readable_str(size, 512, G.disp_hr),
filename);
#else
if (G.disp_k) {
size++;
size >>= 1;
}
printf("%llu\t%s\n", size, filename);
#endif
}
/* tiny recursive du */
static unsigned long long du(const char *filename)
{
struct stat statbuf;
unsigned long long sum;
if (lstat(filename, &statbuf) != 0) {
bb_simple_perror_msg(filename);
G.status = EXIT_FAILURE;
return 0;
}
if (option_mask32 & OPT_x_one_FS) {
if (G.du_depth == 0) {
G.dir_dev = statbuf.st_dev;
} else if (G.dir_dev != statbuf.st_dev) {
return 0;
}
}
sum = statbuf.st_blocks;
if (S_ISLNK(statbuf.st_mode)) {
if (G.slink_depth > G.du_depth) { /* -H or -L */
if (stat(filename, &statbuf) != 0) {
bb_simple_perror_msg(filename);
G.status = EXIT_FAILURE;
return 0;
}
sum = statbuf.st_blocks;
if (G.slink_depth == 1) {
/* Convert -H to -L */
G.slink_depth = INT_MAX;
}
}
}
if (!(option_mask32 & OPT_l_hardlinks)
&& statbuf.st_nlink > 1
) {
/* Add files/directories with links only once */
if (is_in_ino_dev_hashtable(&statbuf)) {
return 0;
}
add_to_ino_dev_hashtable(&statbuf, NULL);
}
if (S_ISDIR(statbuf.st_mode)) {
DIR *dir;
struct dirent *entry;
char *newfile;
dir = warn_opendir(filename);
if (!dir) {
G.status = EXIT_FAILURE;
return sum;
}
while ((entry = readdir(dir))) {
newfile = concat_subpath_file(filename, entry->d_name);
if (newfile == NULL)
continue;
++G.du_depth;
sum += du(newfile);
--G.du_depth;
free(newfile);
}
closedir(dir);
} else {
if (!(option_mask32 & OPT_a_files_too) && G.du_depth != 0)
return sum;
}
if (G.du_depth <= G.max_print_depth) {
print(sum, filename);
}
return sum;
}
int du_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int du_main(int argc UNUSED_PARAM, char **argv)
{
unsigned long long total;
int slink_depth_save;
unsigned opt;
INIT_G();
#if ENABLE_FEATURE_HUMAN_READABLE
IF_FEATURE_DU_DEFAULT_BLOCKSIZE_1K(G.disp_hr = 1024;)
IF_NOT_FEATURE_DU_DEFAULT_BLOCKSIZE_1K(G.disp_hr = 512;)
if (getenv("POSIXLY_CORRECT")) /* TODO - a new libbb function? */
G.disp_hr = 512;
#else
IF_FEATURE_DU_DEFAULT_BLOCKSIZE_1K(G.disp_k = 1;)
/* IF_NOT_FEATURE_DU_DEFAULT_BLOCKSIZE_1K(G.disp_k = 0;) - G is pre-zeroed */
#endif
G.max_print_depth = INT_MAX;
/* Note: SUSv3 specifies that -a and -s options cannot be used together
* in strictly conforming applications. However, it also says that some
* du implementations may produce output when -a and -s are used together.
* gnu du exits with an error code in this case. We choose to simply
* ignore -a. This is consistent with -s being equivalent to -d 0.
*/
#if ENABLE_FEATURE_HUMAN_READABLE
opt_complementary = "h-km:k-hm:m-hk:H-L:L-H:s-d:d-s:d+";
opt = getopt32(argv, "aHkLsx" "d:" "lc" "hm", &G.max_print_depth);
argv += optind;
if (opt & OPT_h_for_humans) {
G.disp_hr = 0;
}
if (opt & OPT_m_mbytes) {
G.disp_hr = 1024*1024;
}
if (opt & OPT_k_kbytes) {
G.disp_hr = 1024;
}
#else
opt_complementary = "H-L:L-H:s-d:d-s:d+";
opt = getopt32(argv, "aHkLsx" "d:" "lc", &G.max_print_depth);
argv += optind;
#if !ENABLE_FEATURE_DU_DEFAULT_BLOCKSIZE_1K
if (opt & OPT_k_kbytes) {
G.disp_k = 1;
}
#endif
#endif
if (opt & OPT_H_follow_links) {
G.slink_depth = 1;
}
if (opt & OPT_L_follow_links) {
G.slink_depth = INT_MAX;
}
if (opt & OPT_s_total_norecurse) {
G.max_print_depth = 0;
}
/* go through remaining args (if any) */
if (!*argv) {
*--argv = (char*)".";
if (G.slink_depth == 1) {
G.slink_depth = 0;
}
}
slink_depth_save = G.slink_depth;
total = 0;
do {
total += du(*argv);
/* otherwise du /dir /dir won't show /dir twice: */
reset_ino_dev_hashtable();
G.slink_depth = slink_depth_save;
} while (*++argv);
if (opt & OPT_c_total)
print(total, "total");
fflush_stdout_and_exit(G.status);
}