diff options
| -rw-r--r-- | include/libbb.h | 2 | ||||
| -rw-r--r-- | libbb/update_passwd.c | 2 | ||||
| -rw-r--r-- | libbb/xreadlink.c | 37 |
3 files changed, 24 insertions, 17 deletions
diff --git a/include/libbb.h b/include/libbb.h index 0170085..1adac84 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -260,10 +260,10 @@ DIR *warn_opendir(const char *path); /* UNUSED: char *xmalloc_realpath(const char *path); */ char *xmalloc_readlink(const char *path); -char *xmalloc_readlink_follow(const char *path); char *xmalloc_readlink_or_warn(const char *path); char *xrealloc_getcwd_or_warn(char *cwd); +char *xmalloc_follow_symlinks(const char *path); //TODO: signal(sid, f) is the same? then why? extern void sig_catch(int,void (*)(int)); diff --git a/libbb/update_passwd.c b/libbb/update_passwd.c index e99db40..d10e863 100644 --- a/libbb/update_passwd.c +++ b/libbb/update_passwd.c @@ -52,7 +52,7 @@ int update_passwd(const char *filename, const char *username, int cnt = 0; int ret = -1; /* failure */ - filename = xmalloc_readlink_follow(filename); + filename = xmalloc_follow_symlinks(filename); if (filename == NULL) return -1; diff --git a/libbb/xreadlink.c b/libbb/xreadlink.c index f7948cb..a5f7eb8 100644 --- a/libbb/xreadlink.c +++ b/libbb/xreadlink.c @@ -33,13 +33,16 @@ char *xmalloc_readlink(const char *path) } /* - * this routine is not the same as realpath(), which canonicalizes - * the given path completely. this routine only follows trailing - * symlinks until a real file is reached, and returns its name. - * intermediate symlinks are not expanded. as above, a malloced - * char* is returned, which must be freed. + * this routine is not the same as realpath(), which + * canonicalizes the given path completely. this routine only + * follows trailing symlinks until a real file is reached, and + * returns its name. if the path ends in a dangling link, or if + * the target doesn't exist, the path is returned in any case. + * intermediate symlinks in the path are not expanded -- only + * those at the tail. + * a malloced char* is returned, which must be freed by the caller. */ -char *xmalloc_readlink_follow(const char *path) +char *xmalloc_follow_symlinks(const char *path) { char *buf; char *lpc; @@ -47,23 +50,27 @@ char *xmalloc_readlink_follow(const char *path) int bufsize; int looping = MAXSYMLINKS + 1; - linkpath = xstrdup(path); + buf = xstrdup(path); goto jump_in; while (1) { - if (!--looping) { - free(linkpath); - free(buf); - return NULL; - } + linkpath = xmalloc_readlink(buf); if (!linkpath) { - if (errno == EINVAL) /* not a symlink */ + /* not a symlink, or doesn't exist */ + if (errno == EINVAL || errno == ENOENT) return buf; free(buf); return NULL; } - if (linkpath[0] != '/') { + + if (!--looping) { + free(linkpath); + free(buf); + return NULL; + } + + if (*linkpath != '/') { bufsize += strlen(linkpath); buf = xrealloc(buf, bufsize); lpc = bb_get_last_path_component_strip(buf); @@ -71,8 +78,8 @@ char *xmalloc_readlink_follow(const char *path) free(linkpath); } else { free(buf); - jump_in: buf = linkpath; + jump_in: bufsize = strlen(buf) + 1; } } |