tor-android/external/badvpn_dns/ncd/modules/run.c

188 lines
5.6 KiB
C

/**
* @file run.c
* @author Ambroz Bizjak <ambrop7@gmail.com>
*
* @section LICENSE
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the author nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* @section DESCRIPTION
*
* Module for running arbitrary programs.
* NOTE: There is no locking - the program may run in parallel with other
* NCD processes and their programs.
*
* Synopsis: run(list do_cmd, list undo_cmd)
* Arguments:
* list do_cmd - Command run on startup. The first element is the full path
* to the executable, other elements are command line arguments (excluding
* the zeroth argument). An empty list is interpreted as no operation.
* list undo_cmd - Command run on shutdown, like do_cmd.
*/
#include <stdlib.h>
#include <string.h>
#include <misc/strdup.h>
#include <ncd/extra/value_utils.h>
#include <ncd/modules/command_template.h>
#include <generated/blog_channel_ncd_run.h>
#define ModuleLog(i, ...) NCDModuleInst_Backend_Log((i), BLOG_CURRENT_CHANNEL, __VA_ARGS__)
static void template_free_func (void *vo, int is_error);
struct instance {
NCDModuleInst *i;
BEventLock lock;
command_template_instance cti;
};
static int build_cmdline (NCDModuleInst *i, NCDValRef args, int remove, char **exec, CmdLine *cl)
{
// read arguments
NCDValRef do_cmd_arg;
NCDValRef undo_cmd_arg;
if (!NCDVal_ListRead(args, 2, &do_cmd_arg, &undo_cmd_arg)) {
ModuleLog(i, BLOG_ERROR, "wrong arity");
goto fail0;
}
if (!NCDVal_IsList(do_cmd_arg) || !NCDVal_IsList(undo_cmd_arg)) {
ModuleLog(i, BLOG_ERROR, "wrong type");
goto fail0;
}
NCDValRef list = (remove ? undo_cmd_arg : do_cmd_arg);
size_t count = NCDVal_ListCount(list);
// check if there is no command
if (count == 0) {
*exec = NULL;
return 1;
}
// read exec
NCDValRef exec_arg = NCDVal_ListGet(list, 0);
if (!NCDVal_IsStringNoNulls(exec_arg)) {
ModuleLog(i, BLOG_ERROR, "wrong type");
goto fail0;
}
if (!(*exec = ncd_strdup(exec_arg))) {
ModuleLog(i, BLOG_ERROR, "ncd_strdup failed");
goto fail0;
}
// start cmdline
if (!CmdLine_Init(cl)) {
ModuleLog(i, BLOG_ERROR, "CmdLine_Init failed");
goto fail1;
}
// add header
if (!CmdLine_Append(cl, *exec)) {
ModuleLog(i, BLOG_ERROR, "CmdLine_Append failed");
goto fail2;
}
// add additional arguments
for (size_t j = 1; j < count; j++) {
NCDValRef arg = NCDVal_ListGet(list, j);
if (!NCDVal_IsStringNoNulls(arg)) {
ModuleLog(i, BLOG_ERROR, "wrong type");
goto fail2;
}
b_cstring arg_cstr = NCDVal_StringCstring(arg);
if (!CmdLine_AppendCstring(cl, arg_cstr, 0, arg_cstr.length)) {
ModuleLog(i, BLOG_ERROR, "CmdLine_AppendCstring failed");
goto fail2;
}
}
// finish
if (!CmdLine_Finish(cl)) {
ModuleLog(i, BLOG_ERROR, "CmdLine_Finish failed");
goto fail2;
}
return 1;
fail2:
CmdLine_Free(cl);
fail1:
free(*exec);
fail0:
return 0;
}
static void func_new (void *vo, NCDModuleInst *i, const struct NCDModuleInst_new_params *params)
{
struct instance *o = vo;
o->i = i;
// init dummy event lock
BEventLock_Init(&o->lock, BReactor_PendingGroup(i->params->iparams->reactor));
command_template_new(&o->cti, i, params, build_cmdline, template_free_func, o, BLOG_CURRENT_CHANNEL, &o->lock);
return;
}
void template_free_func (void *vo, int is_error)
{
struct instance *o = vo;
// free dummy event lock
BEventLock_Free(&o->lock);
if (is_error) {
NCDModuleInst_Backend_DeadError(o->i);
} else {
NCDModuleInst_Backend_Dead(o->i);
}
}
static void func_die (void *vo)
{
struct instance *o = vo;
command_template_die(&o->cti);
}
static struct NCDModule modules[] = {
{
.type = "run",
.func_new2 = func_new,
.func_die = func_die,
.alloc_size = sizeof(struct instance),
.flags = NCDMODULE_FLAG_ACCEPT_NON_CONTINUOUS_STRINGS
}, {
.type = NULL
}
};
const struct NCDModuleGroup ncdmodule_run= {
.modules = modules
};