diff options
Diffstat (limited to 'package/aufs2-util/src/rdu.c')
| -rw-r--r-- | package/aufs2-util/src/rdu.c | 749 |
1 files changed, 0 insertions, 749 deletions
diff --git a/package/aufs2-util/src/rdu.c b/package/aufs2-util/src/rdu.c deleted file mode 100644 index ac958f084..000000000 --- a/package/aufs2-util/src/rdu.c +++ /dev/null @@ -1,749 +0,0 @@ -/* - * Copyright (C) 2009 Junjiro Okajima - * - * This program, aufs is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - */ - -#define _ATFILE_SOURCE -#define _GNU_SOURCE -#define _REENTRANT - -#include <linux/aufs_type.h> -#include <sys/ioctl.h> -#include <sys/stat.h> -#include <sys/types.h> -#include <sys/vfs.h> /* or <sys/statfs.h> */ -#include <assert.h> -#include <dirent.h> -#include <dlfcn.h> -#include <errno.h> -#include <fcntl.h> -#include <pthread.h> -#include <search.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> - -#include "compat.h" - -/* ---------------------------------------------------------------------- */ - -struct rdu { -#ifdef AuRDU_REENTRANT - pthread_rwlock_t lock; -#else - struct dirent de; -#endif - - int fd; - - unsigned long npos, idx; - struct au_rdu_ent **pos; - - unsigned long nent, sz; - struct au_rdu_ent *ent; - - int shwh; - struct au_rdu_ent *real, *wh; -}; - -static struct rdu **rdu; -#define RDU_STEP 8 -static int rdu_cur, rdu_lim = RDU_STEP; - -/* ---------------------------------------------------------------------- */ - -/* #define RduLocalTest */ -#ifdef RduLocalTest -static int rdu_test_data(struct rdu *p, int err) -{ - struct au_rdu_ent *e = p->ent; - static int i; - - if (!i++) { - err = 3; - e->ino = e->type = e->nlen = 1; - strcpy(e->name, "."); - e += au_rdu_len(e->nlen); - e->ino = e->type = e->nlen = 2; - strcpy(e->name, ".."); - e += au_rdu_len(e->nlen); - e->ino = e->type = e->nlen = 3; - strcpy(e->name, "foo"); - } else - err = 0; - - return err; -} -#else -static int rdu_test_data(struct rdu *p, int err) -{ - return err; -} -#endif - -/* #define RduDebug */ -#ifdef RduDebug -#define DPri(fmt, args...) fprintf(stderr, "%s:%d: " fmt, \ - __func__, __LINE__, ##args) -#else -#define DPri(fmt, args...) do {} while (0) -#endif - -/* ---------------------------------------------------------------------- */ - -#ifdef AuRDU_REENTRANT -static void rdu_rwlock_init(struct rdu *p) -{ - pthread_rwlock_init(&p->lock); -} - -static void rdu_read_lock(struct rdu *p) -{ - pthread_rwlock_rdlock(&p->lock); -} - -static void rdu_write_lock(struct rdu *p) -{ - pthread_rwlock_wrlock(&p->lock); -} - -static void rdu_unlock(struct rdu *p) -{ - pthread_rwlock_unlock(&p->lock); -} - -static pthread_mutex_t rdu_lib_mtx = PTHREAD_MUTEX_INITIALIZER; -#define rdu_lib_lock() pthread_mutex_lock(&rdu_lib_mtx) -#define rdu_lib_unlock() pthread_mutex_unlock(&rdu_lib_mtx) -#define rdu_lib_must_lock() assert(pthread_mutex_trylock(&rdu_lib_mtx)) -#else -static void rdu_rwlock_init(struct rdu *p) -{ - /* empty */ -} - -static void rdu_read_lock(struct rdu *p) -{ - /* empty */ -} - -static void rdu_write_lock(struct rdu *p) -{ - /* empty */ -} - -static void rdu_unlock(struct rdu *p) -{ - /* empty */ -} - -#define rdu_lib_lock() do {} while(0) -#define rdu_lib_unlock() do {} while(0) -#define rdu_lib_must_lock() do {} while(0) -#endif - -/* - * initialize this library, particularly global variables. - */ -static int rdu_lib_init(void) -{ - int err; - - err = 0; - if (rdu) - goto out; - - rdu_lib_lock(); - if (!rdu) { - rdu = calloc(rdu_lim, sizeof(*rdu)); - err = !rdu; - } - rdu_lib_unlock(); - - out: - return err; -} - -static int rdu_append(struct rdu *p) -{ - int err, i; - void *t; - - rdu_lib_must_lock(); - - err = 0; - if (rdu_cur < rdu_lim - 1) - rdu[rdu_cur++] = p; - else { - t = realloc(rdu, rdu_lim + RDU_STEP * sizeof(*rdu)); - if (t) { - rdu = t; - rdu_lim += RDU_STEP; - rdu[rdu_cur++] = p; - for (i = 0; i < RDU_STEP - 1; i++) - rdu[rdu_cur + i] = NULL; - } else - err = -1; - } - - return err; -} - -/* ---------------------------------------------------------------------- */ - -static struct rdu *rdu_new(int fd) -{ - struct rdu *p; - int err; - - p = malloc(sizeof(*p)); - if (p) { - rdu_rwlock_init(p); - p->fd = fd; - p->sz = BUFSIZ; - p->ent = malloc(BUFSIZ); - if (p->ent) { - err = rdu_append(p); - if (!err) - goto out; /* success */ - } - } - free(p); - p = NULL; - - out: - return p; -} - -static struct rdu *rdu_buf_lock(int fd) -{ - struct rdu *p; - int i; - - assert(rdu); - assert(fd >= 0); - - p = NULL; - rdu_lib_lock(); - for (i = 0; i < rdu_cur; i++) - if (rdu[i] && rdu[i]->fd == fd) { - p = rdu[i]; - goto out; - } - - for (i = 0; i < rdu_cur; i++) - if (rdu[i] && rdu[i]->fd == -1) { - p = rdu[i]; - p->fd = fd; - goto out; - } - if (!p) - p = rdu_new(fd); - - out: - if (p) - rdu_write_lock(p); - rdu_lib_unlock(); - - return p; -} - -static void rdu_free(int fd) -{ - struct rdu *p; - - p = rdu_buf_lock(fd); - if (p) { - free(p->ent); - free(p->pos); - p->fd = -1; - p->ent = NULL; - p->pos = NULL; - rdu_unlock(p); - } -} - -/* ---------------------------------------------------------------------- */ - -static int rdu_do_store(int dirfd, struct au_rdu_ent *ent, - struct au_rdu_ent **pos, struct rdu *p) -{ - int err; - unsigned char c; - struct stat st; - - c = ent->name[ent->nlen]; - ent->name[ent->nlen] = 0; - DPri("%s\n", ent->name); - err = fstatat(dirfd, ent->name, &st, AT_SYMLINK_NOFOLLOW); - ent->name[ent->nlen] = c; - if (!err) { - ent->ino = st.st_ino; - pos[p->idx++] = ent; - } else { - DPri("err %d\n", err); - if (errno == ENOENT) - err = 0; - } - - return err; -} - -struct rdu_thread_arg { - int pipefd; - struct rdu *p; -}; - -static void *rdu_thread(void *_arg) -{ - int err, pipefd, dirfd; - ssize_t ssz; - struct rdu_thread_arg *arg = _arg; - struct au_rdu_ent *ent, **pos; - struct rdu *p; - - pipefd = arg->pipefd; - p = arg->p; - dirfd = p->fd; - pos = p->pos; - while (1) { - DPri("read\n"); - ssz = read(pipefd, &ent, sizeof(ent)); - DPri("ssz %zd\n", ssz); - if (ssz != sizeof(ent) || !ent) { - //perror("read"); - break; - } - - //DPri("%p\n", ent); - err = rdu_do_store(dirfd, ent, pos, p); - } - - DPri("here\n"); - return NULL; -} - -static int rdu_store(struct rdu *p, struct au_rdu_ent *ent, int pipefd) -{ -#ifdef RduLocalTest - if (ent) - return rdu_do_store(p->fd, ent, p->pos, p); - return 0; -#else - ssize_t ssz; - - //DPri("%p\n", ent); - ssz = write(pipefd, &ent, sizeof(ent)); - DPri("ssz %zd\n", ssz); - //sleep(1); - return ssz != sizeof(ent); -#endif -} - -/* ---------------------------------------------------------------------- */ -/* the heart of this library */ - -static void rdu_tfree(void *node) -{ - /* empty */ -} - -static int rdu_ent_compar(const void *_a, const void *_b) -{ - int ret; - const struct au_rdu_ent *a = _a, *b = _b; - - ret = (int)a->nlen - b->nlen; - if (!ret) - ret = memcmp(a->name, b->name, a->nlen); - return ret; -} - -static int rdu_ent_compar_wh(const void *_a, const void *_b) -{ - int ret; - const struct au_rdu_ent *real = _a, *wh = _b; - - if (real->nlen >= AUFS_WH_PFX_LEN - && !memcmp(real->name, AUFS_WH_PFX, AUFS_WH_PFX_LEN)) { - wh = _a; - real = _b; - } - - ret = (int)wh->nlen - AUFS_WH_PFX_LEN - real->nlen; - if (!ret) - ret = memcmp(wh->name + AUFS_WH_PFX_LEN, real->name, - real->nlen); - return ret; -} - -/* tsearch(3) may not be thread-safe */ -static int rdu_ent_append(struct rdu *p, struct au_rdu_ent *ent, int pipefd) -{ - int err; - struct au_rdu_ent *e; - - err = 0; - e = tfind(ent, (void *)&p->wh, rdu_ent_compar_wh); - if (e) - goto out; - - e = tsearch(ent, (void *)&p->real, rdu_ent_compar); - if (e) - err = rdu_store(p, ent, pipefd); - else - err = -1; - - out: - return err; -} - -static int rdu_ent_append_wh(struct rdu *p, struct au_rdu_ent *ent, int pipefd) -{ - int err; - struct au_rdu_ent *e; - - err = 0; - e = tfind(ent, (void *)&p->wh, rdu_ent_compar); - if (e) - goto out; - - e = tsearch(ent, (void *)&p->wh, rdu_ent_compar); - if (e) { - if (p->shwh) - err = rdu_store(p, ent, pipefd); - } else - err = -1; - - out: - return err; -} - -static int rdu_merge(struct rdu *p) -{ - int err; - unsigned long ul; - pthread_t th; - int fds[2]; - struct rdu_thread_arg arg; - struct au_rdu_ent *ent; - void *t; - - err = -1; - p->pos = malloc(sizeof(*p->pos) * p->npos); - if (!p->pos) - goto out; - - /* pipe(2) may not be scheduled well in linux-2.6.23 and earlier */ - err = pipe(fds); - if (err) - goto out_free; - - arg.pipefd = fds[0]; - arg.p = p; -#ifndef RduLocalTest - err = pthread_create(&th, NULL, rdu_thread, &arg); -#endif - if (err) - goto out_close; - - p->real = NULL; - p->wh = NULL; - ent = p->ent; - for (ul = 0; !err && ul < p->npos; ul++) { - if (ent->nlen <= AUFS_WH_PFX_LEN - || strncmp(ent->name, AUFS_WH_PFX, AUFS_WH_PFX_LEN)) - err = rdu_ent_append(p, ent, fds[1]); - else - err = rdu_ent_append_wh(p, ent, fds[1]); - ent += au_rdu_len(ent->nlen); - } - rdu_store(p, /*ent*/NULL, fds[1]); /* terminate the thread */ - tdestroy(p->real, rdu_tfree); - tdestroy(p->wh, rdu_tfree); - -#ifndef RduLocalTest - pthread_join(th, NULL); -#endif - p->npos = p->idx; - t = realloc(p->pos, sizeof(*p->pos) * p->npos); - if (t) - p->pos = t; - /* t == NULL is not an error */ - - out_close: - close(fds[1]); - close(fds[0]); - if (!err) - goto out; /* success */ - out_free: - free(p->pos); - p->pos = NULL; - out: - return err; -} - -static int rdu_init(struct rdu *p) -{ - int err; - struct aufs_rdu param; - char *t; - - memset(¶m, 0, sizeof(param)); - param.ent = p->ent; - param.sz = p->sz; - t = getenv("AUFS_RDU_BLK"); - if (t) - param.blk = strtoul(t + sizeof("AUFS_RDU_BLK"), NULL, 0); - - do { - err = ioctl(p->fd, AUFS_CTL_RDU, ¶m); - err = rdu_test_data(p, err); - if (err > 0) { - p->npos += err; - if (!param.full) - continue; - - assert(param.blk); - t = realloc(p->ent, p->sz + param.blk); - if (t) { - param.sz = param.blk; - param.ent = (void *)(t + p->sz); - p->ent = (void *)t; - p->sz += param.blk; - } else - err = -1; - } - } while (err > 0); - p->shwh = param.shwh; - if (!err) - err = rdu_merge(p); - - if (err) { - free(p->ent); - p->ent = NULL; - } - - return err; -} - -static int rdu_pos(struct dirent *de, struct rdu *p, long pos) -{ - int err; - struct au_rdu_ent *ent; - - err = -1; - if (pos <= p->npos) { - ent = p->pos[pos]; - de->d_ino = ent->ino; - de->d_off = pos; - de->d_reclen = sizeof(*ent) + ent->nlen; - de->d_type = ent->type; - memcpy(de->d_name, ent->name, ent->nlen); - de->d_name[ent->nlen] = 0; - err = 0; - } - return err; -} - -/* ---------------------------------------------------------------------- */ - -static struct dirent *(*real_readdir)(DIR *dir); -static int (*real_readdir_r)(DIR *dir, struct dirent *de, struct dirent **rde); -static int (*real_closedir)(DIR *dir); - -static int rdu_dl(void **real, char *sym) -{ - char *p; - - if (*real) - return 0; - - dlerror(); /* clear */ - *real = dlsym(RTLD_NEXT, sym); - p = dlerror(); - if (p) - fprintf(stderr, "%s\n", p); - return !!p; -} - -#define RduDlFunc(sym) \ -static int rdu_dl_##sym(void) \ -{ \ - return rdu_dl((void *)&real_##sym, #sym); \ -} - -RduDlFunc(readdir); -RduDlFunc(closedir); - -#ifdef AuRDU_REENTRANT -RduDlFunc(readdir_r); -#else -#define rdu_dl_readdir_r() 1 -#endif - -/* ---------------------------------------------------------------------- */ - -static int rdu_readdir(DIR *dir, struct dirent *de, struct dirent **rde) -{ - int err, fd; - struct rdu *p; - long pos; - struct statfs stfs; - - if (rde) - *rde = NULL; - - errno = EBADF; - fd = dirfd(dir); - err = fd; - if (fd < 0) - goto out; - - err = fstatfs(fd, &stfs); - if (err) - goto out; - - if ( -#ifdef RduLocalTest - 1 || -#endif - stfs.f_type == AUFS_SUPER_MAGIC) { - err = rdu_lib_init(); - if (err) - goto out; - - p = rdu_buf_lock(fd); - if (!p) - goto out; - - pos = telldir(dir); - if (!pos || !p->npos) { - err = rdu_init(p); - rdu_unlock(p); - } - if (err) - goto out; - - rdu_read_lock(p); - if (!de) - de = &p->de; - err = rdu_pos(de, p, pos); - rdu_unlock(p); - if (!err) { - *rde = de; - seekdir(dir, pos + 1); - } - } else if (!de) { - if (!rdu_dl_readdir()) { - err = 0; - *rde = real_readdir(dir); - if (!*rde) - err = -1; - } - } else { - if (!rdu_dl_readdir_r()) - err = real_readdir_r(dir, de, rde); - } - out: - return err; -} - -struct dirent *readdir(DIR *dir) -{ - struct dirent *de; - int err; - - err = rdu_readdir(dir, NULL, &de); - DPri("err %d\n", err); - return de; -} - -#ifdef AuRDU_REENTRANT -int readdir_r(DIR *dirp, struct dirent *de, struct dirent **rde) -{ - return rdu_readdir(dir, de, rde); -} -#endif - -int closedir(DIR *dir) -{ - int err, fd; - struct statfs stfs; - - errno = EBADF; - fd = dirfd(dir); - if (fd < 0) - goto out; - err = fstatfs(fd, &stfs); - if (err) - goto out; - - if (stfs.f_type == AUFS_SUPER_MAGIC) - rdu_free(fd); - if (!rdu_dl_closedir()) - err = real_closedir(dir); - - out: - return err; -} - -#if 0 -extern DIR *opendir (__const char *__name) __nonnull ((1)); -extern int closedir (DIR *__dirp) __nonnull ((1)); -extern struct dirent *__REDIRECT (readdir, (DIR *__dirp), readdir64) - __nonnull ((1)); -extern struct dirent64 *readdir64 (DIR *__dirp) __nonnull ((1)); -extern int readdir_r (DIR *__restrict __dirp, - struct dirent *__restrict __entry, - struct dirent **__restrict __result) - __nonnull ((1, 2, 3)); -extern int readdir64_r (DIR *__restrict __dirp, - struct dirent64 *__restrict __entry, - struct dirent64 **__restrict __result) - __nonnull ((1, 2, 3)); -extern void rewinddir (DIR *__dirp) __THROW __nonnull ((1)); -extern void seekdir (DIR *__dirp, long int __pos) __THROW __nonnull ((1)); -extern long int telldir (DIR *__dirp) __THROW __nonnull ((1)); -extern int dirfd (DIR *__dirp) __THROW __nonnull ((1)); -extern int scandir (__const char *__restrict __dir, - struct dirent ***__restrict __namelist, - int (*__selector) (__const struct dirent *), - int (*__cmp) (__const void *, __const void *)) - __nonnull ((1, 2)); -extern int scandir64 (__const char *__restrict __dir, - struct dirent64 ***__restrict __namelist, - int (*__selector) (__const struct dirent64 *), - int (*__cmp) (__const void *, __const void *)) - __nonnull ((1, 2)); -extern int alphasort (__const void *__e1, __const void *__e2) - __THROW __attribute_pure__ __nonnull ((1, 2)); -extern int alphasort64 (__const void *__e1, __const void *__e2) - __THROW __attribute_pure__ __nonnull ((1, 2)); -extern int versionsort (__const void *__e1, __const void *__e2) - __THROW __attribute_pure__ __nonnull ((1, 2)); -extern int versionsort64 (__const void *__e1, __const void *__e2) - __THROW __attribute_pure__ __nonnull ((1, 2)); -extern __ssize_t getdirentries (int __fd, char *__restrict __buf, - size_t __nbytes, - __off_t *__restrict __basep) - __THROW __nonnull ((2, 4)); -extern __ssize_t getdirentries64 (int __fd, char *__restrict __buf, - size_t __nbytes, - __off64_t *__restrict __basep) - __THROW __nonnull ((2, 4)); -#endif |