busybox/findutils/find.c
2006-11-01 10:25:35 +00:00

569 lines
14 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini find implementation for busybox
*
* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
*
* Reworked by David Douthitt <n9ubh@callsign.net> and
* Matt Kraai <kraai@alumni.carnegiemellon.edu>.
*
* Licensed under the GPL version 2, see the file LICENSE in this tarball.
*/
/* findutils-4.1.20:
*
* # find file.txt -exec 'echo {}' '{} {}' ';'
* find: echo file.txt: No such file or directory
* # find file.txt -exec 'echo' '{} {}' '; '
* find: missing argument to `-exec'
* # find file.txt -exec 'echo {}' '{} {}' ';' junk
* find: paths must precede expression
* # find file.txt -exec 'echo {}' '{} {}' ';' junk ';'
* find: paths must precede expression
* # find file.txt -exec 'echo' '{} {}' ';'
* file.txt file.txt
* (strace: execve("/bin/echo", ["echo", "file.txt file.txt"], [ 30 vars ]))
* # find file.txt -exec 'echo' '{} {}' ';' -print -exec pwd ';'
* file.txt file.txt
* file.txt
* /tmp
* # find -name '*.c' -o -name '*.h'
* [shows files, *.c and *.h intermixed]
* # find file.txt -name '*f*' -o -name '*t*'
* file.txt
* # find file.txt -name '*z*' -o -name '*t*'
* file.txt
* # find file.txt -name '*f*' -o -name '*z*'
* file.txt
*
* # find t z -name '*t*' -print -o -name '*z*'
* t
* # find t z t z -name '*t*' -o -name '*z*' -print
* z
* z
* # find t z t z '(' -name '*t*' -o -name '*z*' ')' -o -print
* (no output)
*/
#include "busybox.h"
#include <fnmatch.h>
USE_FEATURE_FIND_XDEV(static dev_t *xdev_dev;)
USE_FEATURE_FIND_XDEV(static int xdev_count;)
typedef int (*action_fp)(const char *fileName, struct stat *statbuf, void *);
typedef struct {
action_fp f;
} action;
#define ACTS(name, arg...) typedef struct { action a; arg; } action_##name;
#define ACTF(name) static int func_##name(const char *fileName, struct stat *statbuf, action_##name* ap)
ACTS(print)
ACTS(name, char *pattern;)
USE_FEATURE_FIND_PRINT0(ACTS(print0))
USE_FEATURE_FIND_TYPE( ACTS(type, int type_mask;))
USE_FEATURE_FIND_PERM( ACTS(perm, char perm_char; int perm_mask;))
USE_FEATURE_FIND_MTIME( ACTS(mtime, char mtime_char; int mtime_days;))
USE_FEATURE_FIND_MMIN( ACTS(mmin, char mmin_char; int mmin_mins;))
USE_FEATURE_FIND_NEWER( ACTS(newer, time_t newer_mtime;))
USE_FEATURE_FIND_INUM( ACTS(inum, ino_t inode_num;))
USE_FEATURE_FIND_EXEC( ACTS(exec, char **exec_argv; int *subst_count; int exec_argc;))
USE_DESKTOP( ACTS(paren, action ***subexpr;))
USE_DESKTOP( ACTS(prune))
static action ***actions;
static int need_print = 1;
static inline int one_char(const char* str, char c)
{
return (str[0] == c && str[1] == '\0');
}
static int count_subst(const char *str)
{
int count = 0;
while ((str = strstr(str, "{}"))) {
count++;
str++;
}
return count;
}
static char* subst(const char *src, int count, const char* filename)
{
char *buf, *dst, *end;
int flen = strlen(filename);
/* we replace each '{}' with filename: growth by strlen-2 */
buf = dst = xmalloc(strlen(src) + count*(flen-2) + 1);
while ((end = strstr(src, "{}"))) {
memcpy(dst, src, end - src);
dst += end - src;
src = end + 2;
memcpy(dst, filename, flen);
dst += flen;
}
strcpy(dst, src);
return buf;
}
static int exec_actions(action ***appp, const char *fileName, struct stat *statbuf)
{
int cur_group;
int cur_action;
int rc = TRUE;
action **app, *ap;
cur_group = -1;
while ((app = appp[++cur_group])) {
cur_action = -1;
do {
ap = app[++cur_action];
} while (ap && (rc = ap->f(fileName, statbuf, ap)));
if (!ap) {
/* all actions in group were successful */
break;
}
}
return rc;
}
ACTF(name)
{
const char *tmp = strrchr(fileName, '/');
if (tmp == NULL)
tmp = fileName;
else
tmp++;
return fnmatch(ap->pattern, tmp, FNM_PERIOD) == 0;
}
#if ENABLE_FEATURE_FIND_TYPE
ACTF(type)
{
return ((statbuf->st_mode & S_IFMT) == ap->type_mask);
}
#endif
#if ENABLE_FEATURE_FIND_PERM
ACTF(perm)
{
return !((isdigit(ap->perm_char) && (statbuf->st_mode & 07777) == ap->perm_mask)
|| (ap->perm_char == '-' && (statbuf->st_mode & ap->perm_mask) == ap->perm_mask)
|| (ap->perm_char == '+' && (statbuf->st_mode & ap->perm_mask) != 0));
}
#endif
#if ENABLE_FEATURE_FIND_MTIME
ACTF(mtime)
{
time_t file_age = time(NULL) - statbuf->st_mtime;
time_t mtime_secs = ap->mtime_days * 24 * 60 * 60;
return !((isdigit(ap->mtime_char) && file_age >= mtime_secs
&& file_age < mtime_secs + 24 * 60 * 60)
|| (ap->mtime_char == '+' && file_age >= mtime_secs + 24 * 60 * 60)
|| (ap->mtime_char == '-' && file_age < mtime_secs));
}
#endif
#if ENABLE_FEATURE_FIND_MMIN
ACTF(mmin)
{
time_t file_age = time(NULL) - statbuf->st_mtime;
time_t mmin_secs = ap->mmin_mins * 60;
return !((isdigit(ap->mmin_char) && file_age >= mmin_secs
&& file_age < mmin_secs + 60)
|| (ap->mmin_char == '+' && file_age >= mmin_secs + 60)
|| (ap->mmin_char == '-' && file_age < mmin_secs));
}
#endif
#if ENABLE_FEATURE_FIND_NEWER
ACTF(newer)
{
return (ap->newer_mtime >= statbuf->st_mtime);
}
#endif
#if ENABLE_FEATURE_FIND_INUM
ACTF(inum)
{
return (statbuf->st_ino != ap->inode_num);
}
#endif
#if ENABLE_FEATURE_FIND_EXEC
ACTF(exec)
{
int i, rc;
char *argv[ap->exec_argc+1];
for (i = 0; i < ap->exec_argc; i++)
argv[i] = subst(ap->exec_argv[i], ap->subst_count[i], fileName);
argv[i] = NULL; /* terminate the list */
errno = 0;
rc = wait4pid(spawn(argv));
if (errno)
bb_perror_msg("%s", argv[0]);
for (i = 0; i < ap->exec_argc; i++)
free(argv[i]);
return rc == 0; /* return 1 if success */
}
#endif
#if ENABLE_FEATURE_FIND_PRINT0
ACTF(print0)
{
printf("%s%c", fileName, '\0');
return TRUE;
}
#endif
ACTF(print)
{
puts(fileName);
return TRUE;
}
#if ENABLE_DESKTOP
ACTF(paren)
{
return exec_actions(ap->subexpr, fileName, statbuf);
}
/*
* -prune: if -depth is not given, return true and do not descend
* current dir; if -depth is given, return false with no effect.
* Example:
* find dir -name 'asm-*' -prune -o -name '*.[chS]' -print
*/
ACTF(prune)
{
return SKIP;
}
#endif
static int fileAction(const char *fileName, struct stat *statbuf, void* junk, int depth)
{
int rc;
#ifdef CONFIG_FEATURE_FIND_XDEV
if (S_ISDIR(statbuf->st_mode) && xdev_count) {
int i;
for (i = 0; i < xdev_count; i++) {
if (xdev_dev[i] != statbuf->st_dev)
return SKIP;
}
}
#endif
rc = exec_actions(actions, fileName, statbuf);
/* Had no explicit -print[0] or -exec? then print */
if (rc && need_print)
puts(fileName);
/* Cannot return 0: our caller, recursive_action(),
* will perror() and skip dirs (if called on dir) */
return rc == 0 ? TRUE : rc;
}
#if ENABLE_FEATURE_FIND_TYPE
static int find_type(char *type)
{
int mask = 0;
switch (type[0]) {
case 'b':
mask = S_IFBLK;
break;
case 'c':
mask = S_IFCHR;
break;
case 'd':
mask = S_IFDIR;
break;
case 'p':
mask = S_IFIFO;
break;
case 'f':
mask = S_IFREG;
break;
case 'l':
mask = S_IFLNK;
break;
case 's':
mask = S_IFSOCK;
break;
}
if (mask == 0 || type[1] != '\0')
bb_error_msg_and_die(bb_msg_invalid_arg, type, "-type");
return mask;
}
#endif
action*** parse_params(char **argv)
{
action*** appp;
int cur_group = 0;
int cur_action = 0;
action* alloc_action(int sizeof_struct, action_fp f)
{
action *ap;
appp[cur_group] = xrealloc(appp[cur_group], (cur_action+2) * sizeof(*appp));
appp[cur_group][cur_action++] = ap = xmalloc(sizeof_struct);
appp[cur_group][cur_action] = NULL;
ap->f = f;
return ap;
}
#define ALLOC_ACTION(name) (action_##name*)alloc_action(sizeof(action_##name), (action_fp) func_##name)
appp = xzalloc(2 * sizeof(*appp)); /* appp[0],[1] == NULL */
// Actions have side effects and return a true or false value
// We implement: -print, -print0, -exec
// The rest are tests.
// Tests and actions are grouped by operators
// ( expr ) Force precedence
// ! expr True if expr is false
// -not expr Same as ! expr
// expr1 [-a[nd]] expr2 And; expr2 is not evaluated if expr1 is false
// expr1 -o[r] expr2 Or; expr2 is not evaluated if expr1 is true
// expr1 , expr2 List; both expr1 and expr2 are always evaluated
// We implement: (), -a, -o
while (*argv) {
char *arg = argv[0];
char *arg1 = argv[1];
/* --- Operators --- */
if (strcmp(arg, "-a") == 0
USE_DESKTOP(|| strcmp(arg, "-and") == 0)
) {
/* no special handling required */
}
else if (strcmp(arg, "-o") == 0
USE_DESKTOP(|| strcmp(arg, "-or") == 0)
) {
/* start new OR group */
cur_group++;
appp = xrealloc(appp, (cur_group+2) * sizeof(*appp));
appp[cur_group] = NULL;
appp[cur_group+1] = NULL;
cur_action = 0;
}
/* --- Tests and actions --- */
else if (strcmp(arg, "-print") == 0) {
need_print = 0;
(void) ALLOC_ACTION(print);
}
#if ENABLE_FEATURE_FIND_PRINT0
else if (strcmp(arg, "-print0") == 0) {
need_print = 0;
(void) ALLOC_ACTION(print0);
}
#endif
else if (strcmp(arg, "-name") == 0) {
action_name *ap;
if (!*++argv)
bb_error_msg_and_die(bb_msg_requires_arg, arg);
ap = ALLOC_ACTION(name);
ap->pattern = arg1;
}
#if ENABLE_FEATURE_FIND_TYPE
else if (strcmp(arg, "-type") == 0) {
action_type *ap;
if (!*++argv)
bb_error_msg_and_die(bb_msg_requires_arg, arg);
ap = ALLOC_ACTION(type);
ap->type_mask = find_type(arg1);
}
#endif
#if ENABLE_FEATURE_FIND_PERM
/* TODO:
* -perm mode File's permission bits are exactly mode (octal or symbolic).
* Symbolic modes use mode 0 as a point of departure.
* -perm -mode All of the permission bits mode are set for the file.
* -perm +mode Any of the permission bits mode are set for the file.
*/
else if (strcmp(arg, "-perm") == 0) {
action_perm *ap;
if (!*++argv)
bb_error_msg_and_die(bb_msg_requires_arg, arg);
ap = ALLOC_ACTION(perm);
ap->perm_mask = xstrtol_range(arg1, 8, 0, 07777);
ap->perm_char = arg1[0];
if (ap->perm_char == '-')
ap->perm_mask = -ap->perm_mask;
}
#endif
#if ENABLE_FEATURE_FIND_MTIME
else if (strcmp(arg, "-mtime") == 0) {
action_mtime *ap;
if (!*++argv)
bb_error_msg_and_die(bb_msg_requires_arg, arg);
ap = ALLOC_ACTION(mtime);
ap->mtime_days = xatol(arg1);
ap->mtime_char = arg1[0];
if (ap->mtime_char == '-')
ap->mtime_days = -ap->mtime_days;
}
#endif
#if ENABLE_FEATURE_FIND_MMIN
else if (strcmp(arg, "-mmin") == 0) {
action_mmin *ap;
if (!*++argv)
bb_error_msg_and_die(bb_msg_requires_arg, arg);
ap = ALLOC_ACTION(mmin);
ap->mmin_mins = xatol(arg1);
ap->mmin_char = arg1[0];
if (ap->mmin_char == '-')
ap->mmin_mins = -ap->mmin_mins;
}
#endif
#if ENABLE_FEATURE_FIND_NEWER
else if (strcmp(arg, "-newer") == 0) {
action_newer *ap;
struct stat stat_newer;
if (!*++argv)
bb_error_msg_and_die(bb_msg_requires_arg, arg);
xstat(arg1, &stat_newer);
ap = ALLOC_ACTION(newer);
ap->newer_mtime = stat_newer.st_mtime;
}
#endif
#if ENABLE_FEATURE_FIND_INUM
else if (strcmp(arg, "-inum") == 0) {
action_inum *ap;
if (!*++argv)
bb_error_msg_and_die(bb_msg_requires_arg, arg);
ap = ALLOC_ACTION(inum);
ap->inode_num = xatoul(arg1);
}
#endif
#if ENABLE_FEATURE_FIND_EXEC
else if (strcmp(arg, "-exec") == 0) {
int i;
action_exec *ap;
need_print = 0;
ap = ALLOC_ACTION(exec);
ap->exec_argv = ++argv; /* first arg after -exec */
ap->exec_argc = 0;
while (1) {
if (!*argv) /* did not see ';' till end */
bb_error_msg_and_die(bb_msg_requires_arg, arg);
if (one_char(argv[0], ';'))
break;
argv++;
ap->exec_argc++;
}
if (ap->exec_argc == 0)
bb_error_msg_and_die(bb_msg_requires_arg, arg);
ap->subst_count = xmalloc(ap->exec_argc * sizeof(int));
i = ap->exec_argc;
while (i--)
ap->subst_count[i] = count_subst(ap->exec_argv[i]);
}
#endif
#if ENABLE_DESKTOP
else if (one_char(arg, '(')) {
action_paren *ap;
char **endarg;
int nested = 1;
endarg = argv;
while (1) {
if (!*++endarg)
bb_error_msg_and_die("unpaired '('");
if (one_char(*endarg, '('))
nested++;
else if (one_char(*endarg, ')') && !--nested) {
*endarg = NULL;
break;
}
}
ap = ALLOC_ACTION(paren);
ap->subexpr = parse_params(argv + 1);
*endarg = ")"; /* restore NULLed parameter */
argv = endarg;
}
else if (strcmp(arg, "-prune") == 0) {
(void) ALLOC_ACTION(prune);
}
#endif
else
bb_show_usage();
argv++;
}
return appp;
#undef ALLOC_ACTION
}
int find_main(int argc, char **argv)
{
int dereference = FALSE;
char *arg;
char **argp;
int i, firstopt, status = EXIT_SUCCESS;
for (firstopt = 1; firstopt < argc; firstopt++) {
if (argv[firstopt][0] == '-')
break;
#if ENABLE_DESKTOP
if (one_char(argv[firstopt], '('))
break;
#endif
}
if (firstopt == 1) {
argv[0] = ".";
argv--;
firstopt++;
}
// All options always return true. They always take effect,
// rather than being processed only when their place in the
// expression is reached
// We implement: -follow, -xdev
/* Process options, and replace then with -a */
/* (-a will be ignored by recursive parser later) */
argp = &argv[firstopt];
while ((arg = argp[0])) {
if (strcmp(arg, "-follow") == 0) {
dereference = TRUE;
argp[0] = "-a";
}
#if ENABLE_FEATURE_FIND_XDEV
else if (strcmp(arg, "-xdev") == 0) {
struct stat stbuf;
if (!xdev_count) {
xdev_count = firstopt - 1;
xdev_dev = xmalloc(xdev_count * sizeof(dev_t));
for (i = 1; i < firstopt; i++) {
/* not xstat(): shouldn't bomb out on
* "find not_exist exist -xdev" */
if (stat(argv[i], &stbuf)) stbuf.st_dev = -1L;
xdev_dev[i-1] = stbuf.st_dev;
}
}
argp[0] = "-a";
}
argp++;
}
#endif
actions = parse_params(&argv[firstopt]);
for (i = 1; i < firstopt; i++) {
if (!recursive_action(argv[i],
TRUE, // recurse
dereference, // follow links
FALSE, // depth first
fileAction, // file action
fileAction, // dir action
NULL, // user data
0)) // depth
status = EXIT_FAILURE;
}
return status;
}