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-rw-r--r--threadproc/unix/proc.c739
1 files changed, 739 insertions, 0 deletions
diff --git a/threadproc/unix/proc.c b/threadproc/unix/proc.c
new file mode 100644
index 0000000..004772f
--- /dev/null
+++ b/threadproc/unix/proc.c
@@ -0,0 +1,739 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "apr_arch_threadproc.h"
+#include "apr_strings.h"
+#include "apr_portable.h"
+#include "apr_signal.h"
+#include "apr_random.h"
+
+/* Heavy on no'ops, here's what we want to pass if there is APR_NO_FILE
+ * requested for a specific child handle;
+ */
+static apr_file_t no_file = { NULL, -1, };
+
+APR_DECLARE(apr_status_t) apr_procattr_create(apr_procattr_t **new,
+ apr_pool_t *pool)
+{
+ (*new) = (apr_procattr_t *)apr_pcalloc(pool, sizeof(apr_procattr_t));
+
+ if ((*new) == NULL) {
+ return APR_ENOMEM;
+ }
+ (*new)->pool = pool;
+ (*new)->cmdtype = APR_PROGRAM;
+ (*new)->uid = (*new)->gid = -1;
+ return APR_SUCCESS;
+}
+
+APR_DECLARE(apr_status_t) apr_procattr_io_set(apr_procattr_t *attr,
+ apr_int32_t in,
+ apr_int32_t out,
+ apr_int32_t err)
+{
+ apr_status_t rv;
+
+ if ((in != APR_NO_PIPE) && (in != APR_NO_FILE)) {
+ /* APR_CHILD_BLOCK maps to APR_WRITE_BLOCK, while
+ * APR_PARENT_BLOCK maps to APR_READ_BLOCK, so transpose
+ * the CHILD/PARENT blocking flags for the stdin pipe.
+ * stdout/stderr map to the correct mode by default.
+ */
+ if (in == APR_CHILD_BLOCK)
+ in = APR_READ_BLOCK;
+ else if (in == APR_PARENT_BLOCK)
+ in = APR_WRITE_BLOCK;
+
+ if ((rv = apr_file_pipe_create_ex(&attr->child_in, &attr->parent_in,
+ in, attr->pool)) == APR_SUCCESS)
+ rv = apr_file_inherit_unset(attr->parent_in);
+ if (rv != APR_SUCCESS)
+ return rv;
+ }
+ else if (in == APR_NO_FILE)
+ attr->child_in = &no_file;
+
+ if ((out != APR_NO_PIPE) && (out != APR_NO_FILE)) {
+ if ((rv = apr_file_pipe_create_ex(&attr->parent_out, &attr->child_out,
+ out, attr->pool)) == APR_SUCCESS)
+ rv = apr_file_inherit_unset(attr->parent_out);
+ if (rv != APR_SUCCESS)
+ return rv;
+ }
+ else if (out == APR_NO_FILE)
+ attr->child_out = &no_file;
+
+ if ((err != APR_NO_PIPE) && (err != APR_NO_FILE)) {
+ if ((rv = apr_file_pipe_create_ex(&attr->parent_err, &attr->child_err,
+ err, attr->pool)) == APR_SUCCESS)
+ rv = apr_file_inherit_unset(attr->parent_err);
+ if (rv != APR_SUCCESS)
+ return rv;
+ }
+ else if (err == APR_NO_FILE)
+ attr->child_err = &no_file;
+
+ return APR_SUCCESS;
+}
+
+
+APR_DECLARE(apr_status_t) apr_procattr_child_in_set(apr_procattr_t *attr,
+ apr_file_t *child_in,
+ apr_file_t *parent_in)
+{
+ apr_status_t rv = APR_SUCCESS;
+
+ if (attr->child_in == NULL && attr->parent_in == NULL
+ && child_in == NULL && parent_in == NULL)
+ if ((rv = apr_file_pipe_create(&attr->child_in, &attr->parent_in,
+ attr->pool)) == APR_SUCCESS)
+ rv = apr_file_inherit_unset(attr->parent_in);
+
+ if (child_in != NULL && rv == APR_SUCCESS) {
+ if (attr->child_in && (attr->child_in->filedes != -1))
+ rv = apr_file_dup2(attr->child_in, child_in, attr->pool);
+ else {
+ attr->child_in = NULL;
+ if ((rv = apr_file_dup(&attr->child_in, child_in, attr->pool))
+ == APR_SUCCESS)
+ rv = apr_file_inherit_set(attr->child_in);
+ }
+ }
+
+ if (parent_in != NULL && rv == APR_SUCCESS) {
+ if (attr->parent_in)
+ rv = apr_file_dup2(attr->parent_in, parent_in, attr->pool);
+ else
+ rv = apr_file_dup(&attr->parent_in, parent_in, attr->pool);
+ }
+
+ return rv;
+}
+
+
+APR_DECLARE(apr_status_t) apr_procattr_child_out_set(apr_procattr_t *attr,
+ apr_file_t *child_out,
+ apr_file_t *parent_out)
+{
+ apr_status_t rv = APR_SUCCESS;
+
+ if (attr->child_out == NULL && attr->parent_out == NULL
+ && child_out == NULL && parent_out == NULL)
+ if ((rv = apr_file_pipe_create(&attr->parent_out, &attr->child_out,
+ attr->pool)) == APR_SUCCESS)
+ rv = apr_file_inherit_unset(attr->parent_out);
+
+ if (child_out != NULL && rv == APR_SUCCESS) {
+ if (attr->child_out && (attr->child_out->filedes != -1))
+ rv = apr_file_dup2(attr->child_out, child_out, attr->pool);
+ else {
+ attr->child_out = NULL;
+ if ((rv = apr_file_dup(&attr->child_out, child_out, attr->pool))
+ == APR_SUCCESS)
+ rv = apr_file_inherit_set(attr->child_out);
+ }
+ }
+
+ if (parent_out != NULL && rv == APR_SUCCESS) {
+ if (attr->parent_out)
+ rv = apr_file_dup2(attr->parent_out, parent_out, attr->pool);
+ else
+ rv = apr_file_dup(&attr->parent_out, parent_out, attr->pool);
+ }
+
+ return rv;
+}
+
+
+APR_DECLARE(apr_status_t) apr_procattr_child_err_set(apr_procattr_t *attr,
+ apr_file_t *child_err,
+ apr_file_t *parent_err)
+{
+ apr_status_t rv = APR_SUCCESS;
+
+ if (attr->child_err == NULL && attr->parent_err == NULL
+ && child_err == NULL && parent_err == NULL)
+ if ((rv = apr_file_pipe_create(&attr->parent_err, &attr->child_err,
+ attr->pool)) == APR_SUCCESS)
+ rv = apr_file_inherit_unset(attr->parent_err);
+
+ if (child_err != NULL && rv == APR_SUCCESS) {
+ if (attr->child_err && (attr->child_err->filedes != -1))
+ rv = apr_file_dup2(attr->child_err, child_err, attr->pool);
+ else {
+ attr->child_err = NULL;
+ if ((rv = apr_file_dup(&attr->child_err, child_err, attr->pool))
+ == APR_SUCCESS)
+ rv = apr_file_inherit_set(attr->child_err);
+ }
+ }
+ if (parent_err != NULL && rv == APR_SUCCESS) {
+ if (attr->parent_err)
+ rv = apr_file_dup2(attr->parent_err, parent_err, attr->pool);
+ else
+ rv = apr_file_dup(&attr->parent_err, parent_err, attr->pool);
+ }
+
+ return rv;
+}
+
+
+APR_DECLARE(apr_status_t) apr_procattr_dir_set(apr_procattr_t *attr,
+ const char *dir)
+{
+ attr->currdir = apr_pstrdup(attr->pool, dir);
+ if (attr->currdir) {
+ return APR_SUCCESS;
+ }
+
+ return APR_ENOMEM;
+}
+
+APR_DECLARE(apr_status_t) apr_procattr_cmdtype_set(apr_procattr_t *attr,
+ apr_cmdtype_e cmd)
+{
+ attr->cmdtype = cmd;
+ return APR_SUCCESS;
+}
+
+APR_DECLARE(apr_status_t) apr_procattr_detach_set(apr_procattr_t *attr,
+ apr_int32_t detach)
+{
+ attr->detached = detach;
+ return APR_SUCCESS;
+}
+
+APR_DECLARE(apr_status_t) apr_proc_fork(apr_proc_t *proc, apr_pool_t *pool)
+{
+ int pid;
+
+ memset(proc, 0, sizeof(apr_proc_t));
+
+ if ((pid = fork()) < 0) {
+ return errno;
+ }
+ else if (pid == 0) {
+ proc->pid = getpid();
+
+ apr_random_after_fork(proc);
+
+ return APR_INCHILD;
+ }
+
+ proc->pid = pid;
+
+ return APR_INPARENT;
+}
+
+static apr_status_t limit_proc(apr_procattr_t *attr)
+{
+#if APR_HAVE_STRUCT_RLIMIT && APR_HAVE_SETRLIMIT
+#ifdef RLIMIT_CPU
+ if (attr->limit_cpu != NULL) {
+ if ((setrlimit(RLIMIT_CPU, attr->limit_cpu)) != 0) {
+ return errno;
+ }
+ }
+#endif
+#ifdef RLIMIT_NPROC
+ if (attr->limit_nproc != NULL) {
+ if ((setrlimit(RLIMIT_NPROC, attr->limit_nproc)) != 0) {
+ return errno;
+ }
+ }
+#endif
+#ifdef RLIMIT_NOFILE
+ if (attr->limit_nofile != NULL) {
+ if ((setrlimit(RLIMIT_NOFILE, attr->limit_nofile)) != 0) {
+ return errno;
+ }
+ }
+#endif
+#if defined(RLIMIT_AS)
+ if (attr->limit_mem != NULL) {
+ if ((setrlimit(RLIMIT_AS, attr->limit_mem)) != 0) {
+ return errno;
+ }
+ }
+#elif defined(RLIMIT_DATA)
+ if (attr->limit_mem != NULL) {
+ if ((setrlimit(RLIMIT_DATA, attr->limit_mem)) != 0) {
+ return errno;
+ }
+ }
+#elif defined(RLIMIT_VMEM)
+ if (attr->limit_mem != NULL) {
+ if ((setrlimit(RLIMIT_VMEM, attr->limit_mem)) != 0) {
+ return errno;
+ }
+ }
+#endif
+#else
+ /*
+ * Maybe make a note in error_log that setrlimit isn't supported??
+ */
+
+#endif
+ return APR_SUCCESS;
+}
+
+APR_DECLARE(apr_status_t) apr_procattr_child_errfn_set(apr_procattr_t *attr,
+ apr_child_errfn_t *errfn)
+{
+ attr->errfn = errfn;
+ return APR_SUCCESS;
+}
+
+APR_DECLARE(apr_status_t) apr_procattr_error_check_set(apr_procattr_t *attr,
+ apr_int32_t chk)
+{
+ attr->errchk = chk;
+ return APR_SUCCESS;
+}
+
+APR_DECLARE(apr_status_t) apr_procattr_addrspace_set(apr_procattr_t *attr,
+ apr_int32_t addrspace)
+{
+ /* won't ever be used on this platform, so don't save the flag */
+ return APR_SUCCESS;
+}
+
+APR_DECLARE(apr_status_t) apr_procattr_user_set(apr_procattr_t *attr,
+ const char *username,
+ const char *password)
+{
+ apr_status_t rv;
+ apr_gid_t gid;
+
+ if ((rv = apr_uid_get(&attr->uid, &gid, username,
+ attr->pool)) != APR_SUCCESS) {
+ attr->uid = -1;
+ return rv;
+ }
+
+ /* Use default user group if not already set */
+ if (attr->gid == -1) {
+ attr->gid = gid;
+ }
+ return APR_SUCCESS;
+}
+
+APR_DECLARE(apr_status_t) apr_procattr_group_set(apr_procattr_t *attr,
+ const char *groupname)
+{
+ apr_status_t rv;
+
+ if ((rv = apr_gid_get(&attr->gid, groupname, attr->pool)) != APR_SUCCESS)
+ attr->gid = -1;
+ return rv;
+}
+
+APR_DECLARE(apr_status_t) apr_proc_create(apr_proc_t *new,
+ const char *progname,
+ const char * const *args,
+ const char * const *env,
+ apr_procattr_t *attr,
+ apr_pool_t *pool)
+{
+ int i;
+ const char * const empty_envp[] = {NULL};
+
+ if (!env) { /* Specs require an empty array instead of NULL;
+ * Purify will trigger a failure, even if many
+ * implementations don't.
+ */
+ env = empty_envp;
+ }
+
+ new->in = attr->parent_in;
+ new->err = attr->parent_err;
+ new->out = attr->parent_out;
+
+ if (attr->errchk) {
+ if (attr->currdir) {
+ if (access(attr->currdir, X_OK) == -1) {
+ /* chdir() in child wouldn't have worked */
+ return errno;
+ }
+ }
+
+ if (attr->cmdtype == APR_PROGRAM ||
+ attr->cmdtype == APR_PROGRAM_ENV ||
+ *progname == '/') {
+ /* for both of these values of cmdtype, caller must pass
+ * full path, so it is easy to check;
+ * caller can choose to pass full path for other
+ * values of cmdtype
+ */
+ if (access(progname, X_OK) == -1) {
+ /* exec*() in child wouldn't have worked */
+ return errno;
+ }
+ }
+ else {
+ /* todo: search PATH for progname then try to access it */
+ }
+ }
+
+ if ((new->pid = fork()) < 0) {
+ return errno;
+ }
+ else if (new->pid == 0) {
+ /* child process */
+
+ /*
+ * If we do exec cleanup before the dup2() calls to set up pipes
+ * on 0-2, we accidentally close the pipes used by programs like
+ * mod_cgid.
+ *
+ * If we do exec cleanup after the dup2() calls, cleanup can accidentally
+ * close our pipes which replaced any files which previously had
+ * descriptors 0-2.
+ *
+ * The solution is to kill the cleanup for the pipes, then do
+ * exec cleanup, then do the dup2() calls.
+ */
+
+ if (attr->child_in) {
+ apr_pool_cleanup_kill(apr_file_pool_get(attr->child_in),
+ attr->child_in, apr_unix_file_cleanup);
+ }
+
+ if (attr->child_out) {
+ apr_pool_cleanup_kill(apr_file_pool_get(attr->child_out),
+ attr->child_out, apr_unix_file_cleanup);
+ }
+
+ if (attr->child_err) {
+ apr_pool_cleanup_kill(apr_file_pool_get(attr->child_err),
+ attr->child_err, apr_unix_file_cleanup);
+ }
+
+ apr_pool_cleanup_for_exec();
+
+ if ((attr->child_in) && (attr->child_in->filedes == -1)) {
+ close(STDIN_FILENO);
+ }
+ else if (attr->child_in &&
+ attr->child_in->filedes != STDIN_FILENO) {
+ dup2(attr->child_in->filedes, STDIN_FILENO);
+ apr_file_close(attr->child_in);
+ }
+
+ if ((attr->child_out) && (attr->child_out->filedes == -1)) {
+ close(STDOUT_FILENO);
+ }
+ else if (attr->child_out &&
+ attr->child_out->filedes != STDOUT_FILENO) {
+ dup2(attr->child_out->filedes, STDOUT_FILENO);
+ apr_file_close(attr->child_out);
+ }
+
+ if ((attr->child_err) && (attr->child_err->filedes == -1)) {
+ close(STDERR_FILENO);
+ }
+ else if (attr->child_err &&
+ attr->child_err->filedes != STDERR_FILENO) {
+ dup2(attr->child_err->filedes, STDERR_FILENO);
+ apr_file_close(attr->child_err);
+ }
+
+ apr_signal(SIGCHLD, SIG_DFL); /* not sure if this is needed or not */
+
+ if (attr->currdir != NULL) {
+ if (chdir(attr->currdir) == -1) {
+ if (attr->errfn) {
+ attr->errfn(pool, errno, "change of working directory failed");
+ }
+ _exit(-1); /* We have big problems, the child should exit. */
+ }
+ }
+ if (!geteuid()) {
+ apr_procattr_pscb_t *c = attr->perms_set_callbacks;
+
+ while (c) {
+ apr_status_t r;
+ r = (*c->perms_set_fn)((void *)c->data, c->perms,
+ attr->uid, attr->gid);
+ if (r != APR_SUCCESS && r != APR_ENOTIMPL) {
+ _exit(-1);
+ }
+ c = c->next;
+ }
+ }
+ /* Only try to switch if we are running as root */
+ if (attr->gid != -1 && !geteuid()) {
+ if (setgid(attr->gid)) {
+ if (attr->errfn) {
+ attr->errfn(pool, errno, "setting of group failed");
+ }
+ _exit(-1); /* We have big problems, the child should exit. */
+ }
+ }
+
+ if (attr->uid != -1 && !geteuid()) {
+ if (setuid(attr->uid)) {
+ if (attr->errfn) {
+ attr->errfn(pool, errno, "setting of user failed");
+ }
+ _exit(-1); /* We have big problems, the child should exit. */
+ }
+ }
+
+ if (limit_proc(attr) != APR_SUCCESS) {
+ if (attr->errfn) {
+ attr->errfn(pool, errno, "setting of resource limits failed");
+ }
+ _exit(-1); /* We have big problems, the child should exit. */
+ }
+
+ if (attr->cmdtype == APR_SHELLCMD ||
+ attr->cmdtype == APR_SHELLCMD_ENV) {
+ int onearg_len = 0;
+ const char *newargs[4];
+
+ newargs[0] = SHELL_PATH;
+ newargs[1] = "-c";
+
+ i = 0;
+ while (args[i]) {
+ onearg_len += strlen(args[i]);
+ onearg_len++; /* for space delimiter */
+ i++;
+ }
+
+ switch(i) {
+ case 0:
+ /* bad parameters; we're doomed */
+ break;
+ case 1:
+ /* no args, or caller already built a single string from
+ * progname and args
+ */
+ newargs[2] = args[0];
+ break;
+ default:
+ {
+ char *ch, *onearg;
+
+ ch = onearg = apr_palloc(pool, onearg_len);
+ i = 0;
+ while (args[i]) {
+ size_t len = strlen(args[i]);
+
+ memcpy(ch, args[i], len);
+ ch += len;
+ *ch = ' ';
+ ++ch;
+ ++i;
+ }
+ --ch; /* back up to trailing blank */
+ *ch = '\0';
+ newargs[2] = onearg;
+ }
+ }
+
+ newargs[3] = NULL;
+
+ if (attr->detached) {
+ apr_proc_detach(APR_PROC_DETACH_DAEMONIZE);
+ }
+
+ if (attr->cmdtype == APR_SHELLCMD) {
+ execve(SHELL_PATH, (char * const *) newargs, (char * const *)env);
+ }
+ else {
+ execv(SHELL_PATH, (char * const *)newargs);
+ }
+ }
+ else if (attr->cmdtype == APR_PROGRAM) {
+ if (attr->detached) {
+ apr_proc_detach(APR_PROC_DETACH_DAEMONIZE);
+ }
+
+ execve(progname, (char * const *)args, (char * const *)env);
+ }
+ else if (attr->cmdtype == APR_PROGRAM_ENV) {
+ if (attr->detached) {
+ apr_proc_detach(APR_PROC_DETACH_DAEMONIZE);
+ }
+
+ execv(progname, (char * const *)args);
+ }
+ else {
+ /* APR_PROGRAM_PATH */
+ if (attr->detached) {
+ apr_proc_detach(APR_PROC_DETACH_DAEMONIZE);
+ }
+
+ execvp(progname, (char * const *)args);
+ }
+ if (attr->errfn) {
+ char *desc;
+
+ desc = apr_psprintf(pool, "exec of '%s' failed",
+ progname);
+ attr->errfn(pool, errno, desc);
+ }
+
+ _exit(-1); /* if we get here, there is a problem, so exit with an
+ * error code. */
+ }
+
+ /* Parent process */
+ if (attr->child_in && (attr->child_in->filedes != -1)) {
+ apr_file_close(attr->child_in);
+ }
+
+ if (attr->child_out && (attr->child_out->filedes != -1)) {
+ apr_file_close(attr->child_out);
+ }
+
+ if (attr->child_err && (attr->child_err->filedes != -1)) {
+ apr_file_close(attr->child_err);
+ }
+
+ return APR_SUCCESS;
+}
+
+APR_DECLARE(apr_status_t) apr_proc_wait_all_procs(apr_proc_t *proc,
+ int *exitcode,
+ apr_exit_why_e *exitwhy,
+ apr_wait_how_e waithow,
+ apr_pool_t *p)
+{
+ proc->pid = -1;
+ return apr_proc_wait(proc, exitcode, exitwhy, waithow);
+}
+
+APR_DECLARE(apr_status_t) apr_proc_wait(apr_proc_t *proc,
+ int *exitcode, apr_exit_why_e *exitwhy,
+ apr_wait_how_e waithow)
+{
+ pid_t pstatus;
+ int waitpid_options = WUNTRACED;
+ int exit_int;
+ int ignore;
+ apr_exit_why_e ignorewhy;
+
+ if (exitcode == NULL) {
+ exitcode = &ignore;
+ }
+
+ if (exitwhy == NULL) {
+ exitwhy = &ignorewhy;
+ }
+
+ if (waithow != APR_WAIT) {
+ waitpid_options |= WNOHANG;
+ }
+
+ do {
+ pstatus = waitpid(proc->pid, &exit_int, waitpid_options);
+ } while (pstatus < 0 && errno == EINTR);
+
+ if (pstatus > 0) {
+ proc->pid = pstatus;
+
+ if (WIFEXITED(exit_int)) {
+ *exitwhy = APR_PROC_EXIT;
+ *exitcode = WEXITSTATUS(exit_int);
+ }
+ else if (WIFSIGNALED(exit_int)) {
+ *exitwhy = APR_PROC_SIGNAL;
+
+#ifdef WCOREDUMP
+ if (WCOREDUMP(exit_int)) {
+ *exitwhy |= APR_PROC_SIGNAL_CORE;
+ }
+#endif
+
+ *exitcode = WTERMSIG(exit_int);
+ }
+ else {
+ /* unexpected condition */
+ return APR_EGENERAL;
+ }
+
+ return APR_CHILD_DONE;
+ }
+ else if (pstatus == 0) {
+ return APR_CHILD_NOTDONE;
+ }
+
+ return errno;
+}
+
+#if APR_HAVE_STRUCT_RLIMIT
+APR_DECLARE(apr_status_t) apr_procattr_limit_set(apr_procattr_t *attr,
+ apr_int32_t what,
+ struct rlimit *limit)
+{
+ switch(what) {
+ case APR_LIMIT_CPU:
+#ifdef RLIMIT_CPU
+ attr->limit_cpu = limit;
+ break;
+#else
+ return APR_ENOTIMPL;
+#endif
+
+ case APR_LIMIT_MEM:
+#if defined(RLIMIT_DATA) || defined(RLIMIT_VMEM) || defined(RLIMIT_AS)
+ attr->limit_mem = limit;
+ break;
+#else
+ return APR_ENOTIMPL;
+#endif
+
+ case APR_LIMIT_NPROC:
+#ifdef RLIMIT_NPROC
+ attr->limit_nproc = limit;
+ break;
+#else
+ return APR_ENOTIMPL;
+#endif
+
+ case APR_LIMIT_NOFILE:
+#ifdef RLIMIT_NOFILE
+ attr->limit_nofile = limit;
+ break;
+#else
+ return APR_ENOTIMPL;
+#endif
+
+ }
+
+ return APR_SUCCESS;
+}
+#endif /* APR_HAVE_STRUCT_RLIMIT */
+
+APR_DECLARE(apr_status_t) apr_procattr_perms_set_register(apr_procattr_t *attr,
+ apr_perms_setfn_t *perms_set_fn,
+ void *data,
+ apr_fileperms_t perms)
+{
+ apr_procattr_pscb_t *c;
+
+ c = apr_palloc(attr->pool, sizeof(apr_procattr_pscb_t));
+ c->data = data;
+ c->perms = perms;
+ c->perms_set_fn = perms_set_fn;
+ c->next = attr->perms_set_callbacks;
+ attr->perms_set_callbacks = c;
+
+ return APR_SUCCESS;
+}