This finally enables busybox's copy_file() code under a new name (because "copy_file" is already taken in Git code base). Because this comes from busybox, POSIXy (or even Linuxy) behavior is expected. More changes may be needed for Windows support. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@xxxxxxxxx> --- cache.h | 1 + copy.c | 216 ++++++++++++++++++++++++++++++++++++++++++++++++++++------------ 2 files changed, 179 insertions(+), 38 deletions(-) diff --git a/cache.h b/cache.h index 9f09540..213a8d3 100644 --- a/cache.h +++ b/cache.h @@ -1677,6 +1677,7 @@ extern void fprintf_or_die(FILE *, const char *fmt, ...); extern int copy_fd(int ifd, int ofd); extern int copy_file(const char *dst, const char *src, int mode); extern int copy_file_with_time(const char *dst, const char *src, int mode); +extern int copy_dir_recursively(const char *source, const char *dest); extern void write_or_die(int fd, const void *buf, size_t count); extern int write_or_whine(int fd, const void *buf, size_t count, const char *msg); diff --git a/copy.c b/copy.c index 00f8349..f04ac87 100644 --- a/copy.c +++ b/copy.c @@ -1,4 +1,6 @@ #include "cache.h" +#include "dir.h" +#include "hashmap.h" int copy_fd(int ifd, int ofd) { @@ -66,21 +68,126 @@ int copy_file_with_time(const char *dst, const char *src, int mode) return status; } -#if 0 -/* Return: - * -1 error, copy not made - * 0 copy is made or user answered "no" in interactive mode - * (failures to preserve mode/owner/times are not reported in exit code) +struct inode_key { + struct hashmap_entry entry; + ino_t ino; + dev_t dev; + /* + * Reportedly, on cramfs a file and a dir can have same ino. + * Need to also remember "file/dir" bit: + */ + char isdir; /* bool */ +}; + +struct inode_value { + struct inode_key key; + char name[FLEX_ARRAY]; +}; + +#define HASH_SIZE 311u /* Should be prime */ +static inline unsigned hash_inode(ino_t i) +{ + return i % HASH_SIZE; +} + +static int inode_cmp(const void *entry, const void *entry_or_key, + const void *keydata) +{ + const struct inode_value *inode = entry; + const struct inode_key *key = entry_or_key; + + return !(inode->key.ino == key->ino && + inode->key.dev == key->dev && + inode->key.isdir == key->isdir); +} + +static const char *is_in_ino_dev_hashtable(const struct hashmap *map, + const struct stat *st) +{ + struct inode_key key; + struct inode_value *value; + + key.entry.hash = hash_inode(st->st_ino); + key.ino = st->st_ino; + key.dev = st->st_dev; + key.isdir = !!S_ISDIR(st->st_mode); + value = hashmap_get(map, &key, NULL); + return value ? value->name : NULL; +} + +static void add_to_ino_dev_hashtable(struct hashmap *map, + const struct stat *st, + const char *path) +{ + struct inode_value *v; + int len = strlen(path); + + v = xmalloc(offsetof(struct inode_value, name) + len + 1); + v->key.entry.hash = hash_inode(st->st_ino); + v->key.ino = st->st_ino; + v->key.dev = st->st_dev; + v->key.isdir = !!S_ISDIR(st->st_mode); + memcpy(v->name, path, len + 1); + hashmap_add(map, v); +} + +/* + * Find out if the last character of a string matches the one given. + * Don't underrun the buffer if the string length is 0. */ -int FAST_FUNC copy_file(const char *source, const char *dest, int flags) +static inline char *last_char_is(const char *s, int c) +{ + if (s && *s) { + size_t sz = strlen(s) - 1; + s += sz; + if ( (unsigned char)*s == c) + return (char*)s; + } + return NULL; +} + +static inline char *concat_path_file(const char *path, const char *filename) +{ + struct strbuf sb = STRBUF_INIT; + char *lc; + + if (!path) + path = ""; + lc = last_char_is(path, '/'); + while (*filename == '/') + filename++; + strbuf_addf(&sb, "%s%s%s", path, (lc==NULL ? "/" : ""), filename); + return strbuf_detach(&sb, NULL); +} + +static char *concat_subpath_file(const char *path, const char *f) +{ + if (f && is_dot_or_dotdot(f)) + return NULL; + return concat_path_file(path, f); +} + +static int do_unlink(const char *dest) +{ + int e = errno; + + if (unlink(dest) < 0) { + errno = e; /* do not use errno from unlink */ + return sys_error(_("can't create '%s'"), dest); + } + return 0; +} + +static int copy_dir_1(struct hashmap *inode_map, + const char *source, + const char *dest) { /* This is a recursive function, try to minimize stack usage */ - /* NB: each struct stat is ~100 bytes */ struct stat source_stat; struct stat dest_stat; - smallint retval = 0; - smallint dest_exists = 0; - smallint ovr; + int retval = 0; + int dest_exists = 0; + int ovr; if (lstat(source, &source_stat) < 0) return sys_error(_("can't stat '%s'"), source); @@ -102,7 +209,7 @@ int FAST_FUNC copy_file(const char *source, const char *dest, int flags) mode_t saved_umask = 0; /* Did we ever create source ourself before? */ - tp = is_in_ino_dev_hashtable(&source_stat); + tp = is_in_ino_dev_hashtable(inode_map, &source_stat); if (tp) /* We did! it's a recursion! man the lifeboats... */ return error(_("recursion detected, omitting directory '%s'"), @@ -132,11 +239,12 @@ int FAST_FUNC copy_file(const char *source, const char *dest, int flags) if (lstat(dest, &dest_stat) < 0) return sys_error(_("can't stat '%s'"), dest); } + /* * remember (dev,inode) of each created dir. name is * not remembered */ - add_to_ino_dev_hashtable(&dest_stat, NULL); + add_to_ino_dev_hashtable(inode_map, &dest_stat, ""); /* Recursively copy files in SOURCE */ dp = opendir(source); @@ -152,7 +260,7 @@ int FAST_FUNC copy_file(const char *source, const char *dest, int flags) if (!new_source) continue; new_dest = concat_path_file(dest, d->d_name); - if (copy_file(new_source, new_dest, flags & ~FILEUTILS_DEREFERENCE_L0) < 0) + if (copy_dir_1(inode_map, new_source, new_dest) < 0) retval = -1; free(new_source); free(new_dest); @@ -177,53 +285,57 @@ int FAST_FUNC copy_file(const char *source, const char *dest, int flags) goto dont_cat; } - if (ENABLE_FEATURE_PRESERVE_HARDLINKS) { + if (1 /*ENABLE_FEATURE_PRESERVE_HARDLINKS*/) { const char *link_target; - link_target = is_in_ino_dev_hashtable(&source_stat); + link_target = is_in_ino_dev_hashtable(inode_map, &source_stat); if (link_target) { if (link(link_target, dest) < 0) { - ovr = ask_and_unlink(dest, flags); - if (ovr <= 0) + ovr = do_unlink(dest); + if (ovr < 0) return ovr; if (link(link_target, dest) < 0) return sys_error(_("can't create link '%s'"), dest); } return 0; } - add_to_ino_dev_hashtable(&source_stat, dest); + add_to_ino_dev_hashtable(inode_map, &source_stat, dest); } - src_fd = open_or_warn(source, O_RDONLY); + src_fd = open(source, O_RDONLY); if (src_fd < 0) - return -1; + return sys_error(_("can't open '%s'"), source); /* Do not try to open with weird mode fields */ new_mode = source_stat.st_mode; if (!S_ISREG(source_stat.st_mode)) new_mode = 0666; - /* POSIX way is a security problem versus (sym)link attacks */ - if (!ENABLE_FEATURE_NON_POSIX_CP) { - dst_fd = open(dest, O_WRONLY|O_CREAT|O_TRUNC, new_mode); - } else { /* safe way: */ - dst_fd = open(dest, O_WRONLY|O_CREAT|O_EXCL, new_mode); - } + dst_fd = open(dest, O_WRONLY|O_CREAT|O_EXCL, new_mode); if (dst_fd == -1) { - ovr = ask_and_unlink(dest, flags); - if (ovr <= 0) { + ovr = do_unlink(dest); + if (ovr < 0) { close(src_fd); return ovr; } /* It shouldn't exist. If it exists, do not open (symlink attack?) */ - dst_fd = open3_or_warn(dest, O_WRONLY|O_CREAT|O_EXCL, new_mode); + dst_fd = open(dest, O_WRONLY|O_CREAT|O_EXCL, new_mode); if (dst_fd < 0) { close(src_fd); - return -1; + return sys_error(_("can't open '%s'"), dest); } } - if (bb_copyfd_eof(src_fd, dst_fd) == -1) + switch (copy_fd(src_fd, dst_fd)) { + case COPY_READ_ERROR: + error(_("copy-fd: read returned %s"), strerror(errno)); retval = -1; + break; + case COPY_WRITE_ERROR: + error(_("copy-fd: write returned %s"), strerror(errno)); + retval = -1; + break; + } + /* Careful with writing... */ if (close(dst_fd) < 0) retval = sys_error(_("error writing to '%s'"), dest); @@ -243,19 +355,28 @@ dont_cat: /* We are lazy here, a bit lax with races... */ if (dest_exists) { errno = EEXIST; - ovr = ask_and_unlink(dest, flags); - if (ovr <= 0) + ovr = do_unlink(dest); + if (ovr < 0) return ovr; } if (S_ISLNK(source_stat.st_mode)) { - char *lpath = xmalloc_readlink_or_warn(source); - if (lpath) { - int r = symlink(lpath, dest); - free(lpath); + struct strbuf lpath = STRBUF_INIT; + if (!strbuf_readlink(&lpath, source, 0)) { + int r = symlink(lpath.buf, dest); + strbuf_release(&lpath); if (r < 0) return sys_error(_("can't create symlink '%s'"), dest); if (lchown(dest, source_stat.st_uid, source_stat.st_gid) < 0) sys_error(_("can't preserve %s of '%s'"), "ownership", dest); + } else { + /* EINVAL => "file: Invalid argument" => puzzled user */ + const char *errmsg = _("not a symlink"); + int err = errno; + + if (err != EINVAL) + errmsg = strerror(err); + error(_("%s: cannot read link: %s"), source, errmsg); + strbuf_release(&lpath); } /* * _Not_ jumping to preserve_mode_ugid_time: symlinks @@ -293,4 +414,23 @@ preserve_mode_ugid_time: return retval; } -#endif + +/* + * Return: + * -1 error, copy not made + * 0 copy is made + * + * Failures to preserve mode/owner/times are not reported in exit + * code. No support for preserving SELinux security context. Symlinks + * and hardlinks are preserved. + */ +int copy_dir_recursively(const char *source, const char *dest) +{ + int ret; + struct hashmap inode_map; + + hashmap_init(&inode_map, inode_cmp, 1024); + ret = copy_dir_1(&inode_map, source, dest); + hashmap_free(&inode_map, 1); + return ret; +} -- 2.8.0.rc0.210.gd302cd2 -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html