sbase/libutil/recurse.c
Michael Forney edbcc223ea libutil/recurse: Use a single path buffer, and directory fd
This way, we don't use PATH_MAX bytes on the stack per path component,
and don't have to keep copying the complete path around.
2020-03-05 00:45:53 -08:00

107 lines
2.4 KiB
C

/* See LICENSE file for copyright and license details. */
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include "../fs.h"
#include "../util.h"
int recurse_status = 0;
void
recurse(int dirfd, const char *name, void *data, struct recursor *r)
{
struct dirent *d;
struct history *new, *h;
struct stat st, dst;
DIR *dp;
int flags = 0, fd;
size_t pathlen = r->pathlen;
if (dirfd == AT_FDCWD)
pathlen = estrlcpy(r->path, name, sizeof(r->path));
if (r->follow == 'P' || (r->follow == 'H' && r->depth))
flags |= AT_SYMLINK_NOFOLLOW;
if (fstatat(dirfd, name, &st, flags) < 0) {
if (!(r->flags & SILENT)) {
weprintf("stat %s:", r->path);
recurse_status = 1;
}
return;
}
if (!S_ISDIR(st.st_mode)) {
r->fn(dirfd, name, &st, data, r);
return;
}
new = emalloc(sizeof(struct history));
new->prev = r->hist;
r->hist = new;
new->dev = st.st_dev;
new->ino = st.st_ino;
for (h = new->prev; h; h = h->prev)
if (h->ino == st.st_ino && h->dev == st.st_dev)
return;
if (!r->depth && (r->flags & DIRFIRST))
r->fn(dirfd, name, &st, data, r);
if (!r->maxdepth || r->depth + 1 < r->maxdepth) {
fd = openat(dirfd, name, O_RDONLY | O_CLOEXEC | O_DIRECTORY);
if (fd < 0) {
weprintf("open %s:", r->path);
recurse_status = 1;
}
if (!(dp = fdopendir(fd))) {
if (!(r->flags & SILENT)) {
weprintf("fdopendir:");
recurse_status = 1;
}
return;
}
if (r->path[pathlen - 1] != '/')
pathlen += estrlcpy(r->path + pathlen, "/", sizeof(r->path) - pathlen);
if (r->follow == 'H')
flags |= AT_SYMLINK_NOFOLLOW;
while ((d = readdir(dp))) {
if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
continue;
r->pathlen = pathlen + estrlcpy(r->path + pathlen, d->d_name, sizeof(r->path) - pathlen);
if (fstatat(fd, d->d_name, &dst, flags) < 0) {
if (!(r->flags & SILENT)) {
weprintf("stat %s:", r->path);
recurse_status = 1;
}
} else if ((r->flags & SAMEDEV) && dst.st_dev != st.st_dev) {
continue;
} else {
r->depth++;
r->fn(fd, d->d_name, &dst, data, r);
r->depth--;
}
}
closedir(dp);
}
if (!r->depth) {
if (!(r->flags & DIRFIRST))
r->fn(dirfd, name, &st, data, r);
while (r->hist) {
h = r->hist;
r->hist = r->hist->prev;
free(h);
}
}
}