Путь: Toys/POSIX, команды версии: Ver.4 Ver.9 find Комментарии в файле find.c :
Исходный текст в файле find.c #define FOR_find
#include "toys.h"
GLOBALS(
char **filter;
struct double_list *argdata;
int topdir, xdev, depth;
time_t now;
long max_bytes;
char *start;
)
struct execdir_data {
struct execdir_data *next;
int namecount;
struct double_list *names;
};
// None of this can go in TT because you can have more than one -exec
struct exec_range {
char *next, *prev; // layout compatible with struct double_list
int dir, plus, arglen, argsize, curly;
char **argstart;
struct execdir_data exec, *execdir;
};
// Perform pending -exec (if any)
static int flush_exec(struct dirtree *new, struct exec_range *aa)
{
struct execdir_data *bb = aa->execdir ? aa->execdir : &aa->exec;
char **newargs;
int rc, revert = 0;
if (!bb->namecount) return 0;
dlist_terminate(bb->names);
// switch to directory for -execdir, or back to top if we have an -execdir
// _and_ a normal -exec, or are at top of tree in -execdir
if (TT.topdir != -1) {
if (aa->dir && new && new->parent) {
revert++;
rc = fchdir(new->parent->dirfd);
} else rc = fchdir(TT.topdir);
if (rc) {
perror_msg_raw(revert ? new->name : ".");
return rc;
}
}
// execdir: accumulated execs in this directory's children.
newargs = xmalloc(sizeof(char *)*(aa->arglen+bb->namecount+1));
if (aa->curly < 0) {
memcpy(newargs, aa->argstart, sizeof(char *)*aa->arglen);
newargs[aa->arglen] = 0;
} else {
int pos = aa->curly, rest = aa->arglen - aa->curly;
struct double_list *dl;
// Collate argument list
memcpy(newargs, aa->argstart, sizeof(char *)*pos);
for (dl = bb->names; dl; dl = dl->next) newargs[pos++] = dl->data;
rest = aa->arglen - aa->curly - 1;
memcpy(newargs+pos, aa->argstart+aa->curly+1, sizeof(char *)*rest);
newargs[pos+rest] = 0;
}
rc = xrun(newargs);
llist_traverse(bb->names, llist_free_double);
bb->names = 0;
bb->namecount = 0;
if (revert) revert = fchdir(TT.topdir);
return rc;
}
// Return numeric value with explicit sign
static int compare_numsign(long val, long units, char *str)
{
char sign = 0;
long myval;
if (*str == '+' || *str == '-') sign = *(str++);
else if (!isdigit(*str)) error_exit("%s not [+-]N", str);
myval = atolx(str);
if (units && isdigit(str[strlen(str)-1])) myval *= units;
if (sign == '+') return val > myval;
if (sign == '-') return val < myval;
return val == myval;
}
static void do_print(struct dirtree *new, char c)
{
char *s=dirtree_path(new, 0);
xprintf("%s%c", s, c);
free(s);
}
// Descend or ascend -execdir + directory level
static void execdir(struct dirtree *new, int flush)
{
struct double_list *dl;
struct exec_range *aa;
struct execdir_data *bb;
if (new && TT.topdir == -1) return;
for (dl = TT.argdata; dl; dl = dl->next) {
if (dl->prev != (void *)1) continue;
aa = (void *)dl;
if (!aa->plus || (new && !aa->dir)) continue;
if (flush) {
// Flush pending "-execdir +" instances for this dir
// or flush everything for -exec at top
toys.exitval |= flush_exec(new, aa);
// pop per-directory struct
if ((bb = aa->execdir)) {
aa->execdir = bb->next;
free(bb);
}
} else if (aa->dir) {
// Push new per-directory struct for -execdir/okdir + codepath. (Can't
// use new->extra because command line may have multiple -execdir)
bb = xzalloc(sizeof(struct execdir_data));
bb->next = aa->execdir;
aa->execdir = bb;
}
}
}
// Call this with 0 for first pass argument parsing and syntax checking (which
// populates argdata). Later commands traverse argdata (in order) when they
// need "do once" results.
static int do_find(struct dirtree *new)
{
int pcount = 0, print = 0, not = 0, active = !!new, test = active, recurse;
struct double_list *argdata = TT.argdata;
char *s, **ss, *arg;
recurse = DIRTREE_STATLESS|DIRTREE_COMEAGAIN|
(DIRTREE_SYMFOLLOW*!!(toys.optflags&FLAG_L));
// skip . and .. below topdir, handle -xdev and -depth
if (new) {
// Handle stat failures first.
if (new->again&2) {
if (!new->parent || errno != ENOENT) {
perror_msg("'%s'", s = dirtree_path(new, 0));
free(s);
}
return 0;
}
if (new->parent) {
if (!dirtree_notdotdot(new)) return 0;
if (TT.xdev && new->st.st_dev != new->parent->st.st_dev) recurse = 0;
} else TT.start = new->name;
if (S_ISDIR(new->st.st_mode)) {
// Descending into new directory
if (!new->again) {
struct dirtree *n;
for (n = new->parent; n; n = n->parent) {
if (same_file(&n->st, &new->st)) {
error_msg("'%s': loop detected", s = dirtree_path(new, 0));
free(s);
return 0;
}
}
if (TT.depth) {
execdir(new, 0);
return recurse;
}
// Done with directory (COMEAGAIN call)
} else {
execdir(new, 1);
recurse = 0;
if (!TT.depth) return 0;
}
}
}
// pcount: parentheses stack depth (using toybuf bytes, 4096 max depth)
// test: result of most recent test
// active: if 0 don't perform tests
// not: a pending ! applies to this test (only set if performing tests)
// print: saw one of print/ok/exec, no need for default -print
if (TT.filter) for (ss = TT.filter; (s = *ss); ss++) {
int check = active && test;
// if (!new) perform one-time setup, if (check) perform test
// handle ! ( ) using toybuf as a stack
if (*s != '-') {
if (s[1]) goto error;
if (*s == '!') {
// Don't invert if we're not making a decision
if (check) not = !not;
// Save old "not" and "active" on toybuf stack.
// Deactivate this parenthetical if !test
// Note: test value should never change while !active
} else if (*s == '(') {
if (pcount == sizeof(toybuf)) goto error;
toybuf[pcount++] = not+(active<<1);
if (!check) active = 0;
not = 0;
// Pop status, apply deferred not to test
} else if (*s == ')') {
if (--pcount < 0) goto error;
// Pop active state, apply deferred not (which was only set if checking)
active = (toybuf[pcount]>>1)&1;
if (active && (toybuf[pcount]&1)) test = !test;
not = 0;
} else goto error;
continue;
} else s++;
if (!strcmp(s, "xdev")) TT.xdev = 1;
else if (!strcmp(s, "delete")) {
// Delete forces depth first
TT.depth = 1;
if (new && check)
test = !unlinkat(dirtree_parentfd(new), new->name,
S_ISDIR(new->st.st_mode) ? AT_REMOVEDIR : 0);
} else if (!strcmp(s, "depth") || !strcmp(s, "d")) TT.depth = 1;
else if (!strcmp(s, "o") || !strcmp(s, "or")) {
if (not) goto error;
if (active) {
if (!test) test = 1;
else active = 0; // decision has been made until next ")"
}
} else if (!strcmp(s, "not")) {
if (check) not = !not;
continue;
} else if (!strcmp(s, "true")) {
if (check) test = 1;
} else if (!strcmp(s, "false")) {
if (check) test = 0;
// Mostly ignore NOP argument
} else if (!strcmp(s, "a") || !strcmp(s, "and") || !strcmp(s, "noleaf")) {
if (not) goto error;
} else if (!strcmp(s, "print") || !strcmp("print0", s)) {
print++;
if (check) do_print(new, s[5] ? 0 : '\n');
} else if (!strcmp(s, "empty")) {
if (check) {
// Alas neither st_size nor st_blocks reliably show an empty directory
if (S_ISDIR(new->st.st_mode)) {
int fd = openat(dirtree_parentfd(new), new->name, O_RDONLY);
DIR *dfd = fdopendir(fd);
struct dirent *de = (void *)1;
if (dfd) {
while ((de = readdir(dfd)) && isdotdot(de->d_name));
closedir(dfd);
}
if (de) test = 0;
} else if (S_ISREG(new->st.st_mode)) {
if (new->st.st_size) test = 0;
} else test = 0;
}
} else if (!strcmp(s, "nouser")) {
if (check && bufgetpwuid(new->st.st_uid)) test = 0;
} else if (!strcmp(s, "nogroup")) {
if (check && bufgetgrgid(new->st.st_gid)) test = 0;
} else if (!strcmp(s, "prune")) {
if (check && S_ISDIR(new->st.st_mode) && !TT.depth) recurse = 0;
} else if (!strcmp(s, "executable")) {
if (check && faccessat(dirtree_parentfd(new), new->name,X_OK,0)) test = 0;
} else if (!strcmp(s, "quit")) {
if (check) {
execdir(0, 1);
xexit();
}
// Remaining filters take an argument
} else {
arg = *++ss;
if (!strcmp(s, "name") || !strcmp(s, "iname")
|| !strcmp(s, "wholename") || !strcmp(s, "iwholename")
|| !strcmp(s, "path") || !strcmp(s, "ipath")
|| !strcmp(s, "lname") || !strcmp(s, "ilname"))
{
int i = (*s == 'i'), is_path = (s[i] != 'n');
char *path = 0, *name = new ? new->name : arg;
// Handle path expansion and case flattening
if (new && s[i] == 'l')
name = path = xreadlinkat(dirtree_parentfd(new), new->name);
else if (new && is_path) name = path = dirtree_path(new, 0);
if (i) {
if ((check || !new) && name) name = strlower(name);
if (!new) dlist_add(&TT.argdata, name);
else arg = ((struct double_list *)llist_pop(&argdata))->data;
}
if (check) {
test = !fnmatch(arg, path ? name : basename(name),
FNM_PATHNAME*(!is_path));
if (i) free(name);
}
free(path);
} else if (!CFG_TOYBOX_LSM_NONE && !strcmp(s, "context")) {
if (check) {
char *path = dirtree_path(new, 0), *context;
if (lsm_get_context(path, &context) != -1) {
test = !fnmatch(arg, context, 0);
free(context);
} else test = 0;
free(path);
}
} else if (!strcmp(s, "perm")) {
if (check) {
int match_min = *arg == '-', match_any = *arg == '/';
mode_t m1 = string_to_mode(arg+(match_min || match_any), 0),
m2 = new->st.st_mode & 07777;
if (match_min || match_any) m2 &= m1;
test = match_any ? !m1 || m2 : m1 == m2;
}
} else if (!strcmp(s, "type")) {
if (check) {
int types[] = {S_IFBLK, S_IFCHR, S_IFDIR, S_IFLNK, S_IFIFO,
S_IFREG, S_IFSOCK}, i;
for (; *arg; arg++) {
if (*arg == ',') continue;
i = stridx("bcdlpfs", *arg);
if (i<0) error_exit("bad -type '%c'", *arg);
if ((new->st.st_mode & S_IFMT) == types[i]) break;
}
test = *arg;
}
} else if (strchr("acm", *s)
&& (!strcmp(s+1, "time") || !strcmp(s+1, "min")))
{
if (check) {
time_t thyme = (int []){new->st.st_atime, new->st.st_ctime,
new->st.st_mtime}[stridx("acm", *s)];
int len = strlen(arg), uu, units = (s[1]=='m') ? 60 : 86400;
if (len && -1!=(uu = stridx("dhms",tolower(arg[len-1])))) {
arg = xstrdup(arg);
arg[--len] = 0;
units = (int []){86400, 3600, 60, 1}[uu];
}
test = compare_numsign(TT.now - thyme, units, arg);
if (*ss != arg) free(arg);
}
} else if (!strcmp(s, "size")) {
if (check) test = compare_numsign(new->st.st_size, 512, arg);
} else if (!strcmp(s, "links")) {
if (check) test = compare_numsign(new->st.st_nlink, 0, arg);
} else if (!strcmp(s, "inum")) {
if (check) test = compare_numsign(new->st.st_ino, 0, arg);
} else if (!strcmp(s, "mindepth") || !strcmp(s, "maxdepth")) {
if (check) {
struct dirtree *dt = new;
int i = 0, d = atolx(arg);
while ((dt = dt->parent)) i++;
if (s[1] == 'i') {
test = i >= d;
if (i == d && not) recurse = 0;
} else {
test = i <= d;
if (i == d && !not) recurse = 0;
}
}
} else if (!strcmp(s, "user") || !strcmp(s, "group")
|| !strncmp(s, "newer", 5) || !strcmp(s, "samefile"))
{
int macoff[] = {offsetof(struct stat, st_mtim),
offsetof(struct stat, st_atim), offsetof(struct stat, st_ctim)};
struct {
void *next, *prev;
union {
uid_t uid;
gid_t gid;
struct timespec tm;
struct dev_ino di;
};
} *udl;
struct stat st;
if (!new) {
if (arg) {
udl = xmalloc(sizeof(*udl));
dlist_add_nomalloc(&TT.argdata, (void *)udl);
if (strchr("sn", *s)) {
if (*s=='n' && s[5] && (s[7] || !strchr("Bmac", s[5]) || !strchr("tBmac", s[6])))
goto error;
if (*s=='s' || !s[5] || s[6]!='t') {
xstat(arg, &st);
if (*s=='s') udl->di.dev = st.st_dev, udl->di.ino = st.st_ino;
else udl->tm = *(struct timespec *)(((char *)&st)
+ macoff[!s[5] ? 0 : stridx("ac", s[6])+1]);
} else if (s[6] == 't') {
unsigned nano;
xparsedate(arg, &(udl->tm.tv_sec), &nano, 1);
udl->tm.tv_nsec = nano;
}
} else if (*s == 'u') udl->uid = xgetuid(arg);
else udl->gid = xgetgid(arg);
}
} else {
udl = (void *)llist_pop(&argdata);
if (check) {
if (*s == 'u') test = new->st.st_uid == udl->uid;
else if (*s == 'g') test = new->st.st_gid == udl->gid;
else if (*s == 's') test = same_dev_ino(&new->st, &udl->di);
else {
struct timespec *tm = (void *)(((char *)&new->st)
+ macoff[!s[5] ? 0 : stridx("ac", s[5])+1]);
if (s[5] == 'B') test = 0;
else test = (tm->tv_sec == udl->tm.tv_sec)
? tm->tv_nsec > udl->tm.tv_nsec
: tm->tv_sec > udl->tm.tv_sec;
}
}
}
} else if (!strcmp(s, "exec") || !strcmp("ok", s)
|| !strcmp(s, "execdir") || !strcmp(s, "okdir"))
{
struct exec_range *aa;
print++;
// Initial argument parsing pass
if (!new) {
int len;
// catch "-exec" with no args and "-exec \;"
if (!arg || !strcmp(arg, ";")) error_exit("'%s' needs 1 arg", s);
dlist_add_nomalloc(&TT.argdata, (void *)(aa = xzalloc(sizeof(*aa))));
aa->argstart = ss;
aa->curly = -1;
// Record command line arguments to -exec
for (len = 0; ss[len]; len++) {
if (!strcmp(ss[len], ";")) break;
else if (!strcmp(ss[len], "{}")) {
aa->curly = len;
if (ss[len+1] && !strcmp(ss[len+1], "+")) {
aa->plus++;
len++;
break;
}
} else aa->argsize += sizeof(char *) + strlen(ss[len]) + 1;
}
if (!ss[len]) error_exit("-exec without %s",
aa->curly!=-1 ? "\\;" : "{}");
ss += len;
aa->arglen = len;
aa->dir = !!strchr(s, 'd');
if (TT.topdir == -1) TT.topdir = xopenro(".");
// collect names and execute commands
} else {
char *name;
struct execdir_data *bb;
// Grab command line exec argument list
aa = (void *)llist_pop(&argdata);
ss += aa->arglen;
if (!check) goto cont;
// name is always a new malloc, so we can always free it.
name = aa->dir ? xstrdup(new->name) : dirtree_path(new, 0);
if (*s == 'o') {
fprintf(stderr, "[%s] %s", arg, name);
if (!(test = yesno(0))) {
free(name);
goto cont;
}
}
// Add next name to list (global list without -dir, local with)
bb = aa->execdir ? aa->execdir : &aa->exec;
dlist_add(&bb->names, name);
bb->namecount++;
// -exec + collates and saves result in exitval
if (aa->plus) {
// Mark entry so COMEAGAIN can call flush_exec() in parent.
// This is never a valid pointer value for prev to have otherwise
// Done here vs argument parsing pass so it's after dlist_terminate
aa->prev = (void *)1;
// Flush if the child's environment space gets too large.
// Linux caps individual arguments/variables at 131072 bytes,
// so this counter can't wrap.
if ((aa->plus += sizeof(char *)+strlen(name)+1) > TT.max_bytes) {
aa->plus = 1;
toys.exitval |= flush_exec(new, aa);
}
} else test = !flush_exec(new, aa);
}
// Argument consumed, skip the check.
goto cont;
} else if (!strcmp(s, "printf")) {
char *fmt, *ff, next[32], buf[64], ch;
long ll;
int len;
print++;
if (check) for (fmt = arg; *fmt; fmt++) {
// Print the parts that aren't escapes
if (*fmt == '\\') {
unsigned u;
if (fmt[1] == 'c') break;
if ((u = unescape2(&fmt, 0))<128) putchar(u);
else printf("%.*s", (int)wcrtomb(buf, u, 0), buf);
fmt--;
} else if (*fmt != '%') putchar(*fmt);
else if (*++fmt == '%') putchar('%');
else {
fmt = next_printf(ff = fmt-1, 0);
if ((len = fmt-ff)>28) error_exit("bad %.*s", len+1, ff);
memcpy(next, ff, len);
ff = 0;
ch = *fmt;
// long long is its own stack size on LP64, so handle separately
if (ch == 'i' || ch == 's') {
strcpy(next+len, "lld");
printf(next, (ch == 'i') ? (long long)new->st.st_ino
: (long long)new->st.st_size);
} else {
// LP64 says these are all a single "long" argument to printf
strcpy(next+len, "s");
if (ch == 'G') next[len] = 'd', ll = new->st.st_gid;
else if (ch == 'm') next[len] = 'o', ll = new->st.st_mode&~S_IFMT;
else if (ch == 'U') next[len] = 'd', ll = new->st.st_uid;
else if (ch == 'f') ll = (long)new->name;
else if (ch == 'g') ll = (long)getgroupname(new->st.st_gid);
else if (ch == 'u') ll = (long)getusername(new->st.st_uid);
else if (ch == 'l') {
ll = (long)(ff = xreadlinkat(dirtree_parentfd(new), new->name));
if (!ll) ll = (long)"";
} else if (ch == 'M') {
mode_to_string(new->st.st_mode, buf);
ll = (long)buf;
} else if (ch == 'P') {
ch = *TT.start;
*TT.start = 0;
ll = (long)(ff = dirtree_path(new, 0));
*TT.start = ch;
} else if (ch == 'p') ll = (long)(ff = dirtree_path(new, 0));
else if (ch == 'T') {
if (*++fmt!='@') error_exit("bad -printf %%T: %%T%c", *fmt);
sprintf(buf, "%lld.%ld", (long long)new->st.st_mtim.tv_sec,
new->st.st_mtim.tv_nsec);
ll = (long)buf;
} else if (ch == 'Z') {
char *path = dirtree_path(new, 0);
ll = (lsm_get_context(path, &ff) != -1) ? (long)ff : (long)"?";
free(path);
} else error_exit("bad -printf %%%c", ch);
printf(next, ll);
free(ff);
}
}
}
} else goto error;
// This test can go at the end because we do a syntax checking
// pass first. Putting it here gets the error message (-unknown
// vs -known noarg) right.
if (!check && !arg) error_exit("'%s' needs 1 arg", s-1);
}
cont:
// Apply pending "!" to result
if (active && not) test = !test;
not = 0;
}
if (new) {
// If there was no action, print
if (!print && test) do_print(new, '\n');
if (S_ISDIR(new->st.st_mode)) execdir(new, 0);
} else dlist_terminate(TT.argdata);
return recurse;
error:
error_exit("bad arg '%s'", *ss);
}
void find_main(void)
{
int i, len;
char **ss = (char *[]){"."};
TT.topdir = -1;
TT.max_bytes = sysconf(_SC_ARG_MAX) - environ_bytes();
// Distinguish paths from filters
for (len = 0; toys.optargs[len]; len++)
if (*toys.optargs[len] && strchr("-!(", *toys.optargs[len])) break;
TT.filter = toys.optargs+len;
// use "." if no paths
if (len) ss = toys.optargs;
else len = 1;
// first pass argument parsing, verify args match up, handle "evaluate once"
TT.now = time(0);
do_find(0);
// Loop through paths
for (i = 0; i < len; i++)
dirtree_flagread(ss[i],
DIRTREE_STATLESS|(DIRTREE_SYMFOLLOW*!!(toys.optflags&(FLAG_H|FLAG_L))),
do_find);
execdir(0, 1);
if (CFG_TOYBOX_FREE) {
close(TT.topdir);
llist_traverse(TT.argdata, free);
}
} |
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