libposix: complete POSIX_signal_execute

This commit is contained in:
Giacomo Tesio 2017-05-03 03:02:56 +02:00
parent 3b35743a64
commit d29859684b
5 changed files with 202 additions and 144 deletions

View File

@ -16,7 +16,8 @@
"initlib.c",
"memory.c",
"others.c",
"processes.c"
"processes.c",
"signals.c"
]
}
}

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@ -30,6 +30,7 @@ libposix_check_configuration(void)
__libposix_errors_check_conf();
__libposix_files_check_conf();
__libposix_processes_check_conf();
__libposix_signal_check_conf();
}
void

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@ -26,6 +26,7 @@ struct WaitList
extern void __libposix_files_check_conf(void);
extern void __libposix_errors_check_conf(void);
extern void __libposix_processes_check_conf(void);
extern void __libposix_signal_check_conf(void);
extern int __libposix_initialized(void);
extern int __libposix_get_errno(PosixError e);
@ -35,3 +36,5 @@ extern void __libposix_setup_exec_environment(char * const *env);
extern int __libposix_translate_errstr(uintptr_t caller);
extern int __libposix_note_handler(void *ureg, char *note);
extern void __libposix_free_wait_list(void);

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@ -23,14 +23,13 @@
extern char **environ;
WaitList **__libposix_wait_list;
static PosixSignalTrampoline __libposix_signal_trampoline;
static PosixExitStatusTranslator __libposix_exit_status_translator;
static int __libposix_wnohang;
#define __POSIX_SIGNAL_PREFIX_LEN (sizeof(__POSIX_SIGNAL_PREFIX)-1)
static void
free_wait_list(void)
void
__libposix_free_wait_list(void)
{
WaitList *wl, *c;
@ -53,7 +52,7 @@ POSIX_exit(int code)
{
char buf[64], *s;
free_wait_list();
__libposix_free_wait_list();
if(__libposix_exit_status_translator != nil
&&(s = __libposix_exit_status_translator(code)) != nil){
@ -80,7 +79,7 @@ POSIX_execve(int *errnop, const char *name, char * const*argv, char * const*env)
__libposix_setup_exec_environment(env);
}
free_wait_list();
__libposix_free_wait_list();
ret = sys_exec(name, argv);
switch(ret){
@ -96,6 +95,30 @@ POSIX_execve(int *errnop, const char *name, char * const*argv, char * const*env)
return -1;
}
int
POSIX_getpid(int *errnop)
{
return getpid();
}
int
POSIX_getppid(int *errnop)
{
return getppid();
}
int
POSIX_fork(int *errnop)
{
int pid = fork();
if(pid == 0){
/* reset wait list for the child */
*__libposix_wait_list = nil;
}
return pid;
}
int
POSIX_wait(int *errnop, int *status)
{
@ -244,131 +267,6 @@ WaitAgain:
return -1;
}
static int
note_all_writable_processes(int *errnop, char *note)
{
// TODO: loop over writable note files and post note.
*errnop = __libposix_get_errno(PosixEPERM);
return -1;
}
int
POSIX_kill(int *errnop, int pid, int sig)
{
char msg[64], file[128];
int mode;
int ret;
snprint(msg, sizeof(msg), __POSIX_SIGNAL_PREFIX "%d", sig);
switch(pid){
case 0:
mode = PNGROUP;
break;
case -1:
return note_all_writable_processes(errnop, msg);
default:
if(pid < 0){
mode = PNGROUP;
pid = -pid;
} else {
mode = PNPROC;
}
}
snprint(file, sizeof(file), "/proc/%d/note", pid);
if(access(file, AWRITE) != 0){
if(access(file, AEXIST) == 0)
*errnop = __libposix_get_errno(PosixEPERM);
else
*errnop = __libposix_get_errno(PosixESRCH);
return -1;
}
ret = postnote(mode, pid, msg);
if(ret != 0){
*errnop = __libposix_translate_errstr((uintptr_t)POSIX_kill);
return -1;
}
return 0;
}
int
POSIX_getpid(int *errnop)
{
return getpid();
}
int
POSIX_getppid(int *errnop)
{
return getppid();
}
int
POSIX_fork(int *errnop)
{
int pid = fork();
if(pid == 0){
/* reset wait list for the child */
*__libposix_wait_list = nil;
}
return pid;
}
static int
translate_jehanne_note(char *note)
{
// TODO: implement
return 0;
}
static void
terminated_by_signal(int sig)
{
char buf[64];
free_wait_list();
snprint(buf, sizeof(buf), __POSIX_EXIT_SIGNAL_PREFIX "%d", sig);
exits(buf);
}
int
POSIX_signal_execute(int sig, PosixSignalDisposition action, int pid)
{
switch(action){
case SignalHandled:
return 1;
case TerminateTheProcess:
case TerminateTheProcessAndCoreDump:
terminated_by_signal(sig);
break;
case StopTheProcess:
if(pid < 0)
sysfatal("libposix: stop signal reached the target process");
// TODO: write stop to ctl file
return 1;
case ResumeTheProcess:
if(pid < 0)
sysfatal("libposix: continue signal reached the target process");
// TODO: write start to ctl file
return 1;
}
return 0;
}
int
__libposix_note_handler(void *ureg, char *note)
{
int sig;
PosixSignalDisposition action;
if(strncmp(note, __POSIX_SIGNAL_PREFIX, __POSIX_SIGNAL_PREFIX_LEN) != 0)
return translate_jehanne_note(note); // TODO: should we translate common notes?
sig = atoi(note+__POSIX_SIGNAL_PREFIX_LEN);
action = __libposix_signal_trampoline(sig);
return POSIX_signal_execute(sig, action, -1);
}
int
libposix_translate_exit_status(PosixExitStatusTranslator translator)
{
@ -380,17 +278,6 @@ libposix_translate_exit_status(PosixExitStatusTranslator translator)
return 1;
}
int
libposix_set_signal_trampoline(PosixSignalTrampoline trampoline)
{
if(__libposix_initialized())
return 0;
if(trampoline == nil)
return 0;
__libposix_signal_trampoline = trampoline;
return 1;
}
int
libposix_set_wait_options(int wcontinued, int wnohang, int wuntraced)
{
@ -405,8 +292,6 @@ libposix_set_wait_options(int wcontinued, int wnohang, int wuntraced)
void
__libposix_processes_check_conf(void)
{
if(__libposix_signal_trampoline == nil)
sysfatal("libposix: no signal trampoline");
if(__libposix_wnohang == 0)
sysfatal("libposix: WNOHANG is undefined");
/* __libposix_exit_status_translator is optional */

168
sys/src/lib/posix/signals.c Normal file
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@ -0,0 +1,168 @@
/*
* This file is part of Jehanne.
*
* Copyright (C) 2017 Giacomo Tesio <giacomo@tesio.it>
*
* This is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, version 3 of the License.
*
* Jehanne 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 Affero General Public License
* along with Jehanne. If not, see <http://www.gnu.org/licenses/>.
*/
#include <u.h>
#include <lib9.h>
#include <posix.h>
#include "internal.h"
#define __POSIX_SIGNAL_PREFIX_LEN (sizeof(__POSIX_SIGNAL_PREFIX)-1)
static PosixSignalTrampoline __libposix_signal_trampoline;
static int
note_all_writable_processes(int *errnop, char *note)
{
// TODO: loop over writable note files and post note.
*errnop = __libposix_get_errno(PosixEPERM);
return -1;
}
int
POSIX_kill(int *errnop, int pid, int sig)
{
char msg[64], file[128];
int mode;
int ret;
snprint(msg, sizeof(msg), __POSIX_SIGNAL_PREFIX "%d", sig);
switch(pid){
case 0:
mode = PNGROUP;
break;
case -1:
return note_all_writable_processes(errnop, msg);
default:
if(pid < 0){
mode = PNGROUP;
pid = -pid;
} else {
mode = PNPROC;
}
}
snprint(file, sizeof(file), "/proc/%d/note", pid);
if(access(file, AWRITE) != 0){
if(access(file, AEXIST) == 0)
*errnop = __libposix_get_errno(PosixEPERM);
else
*errnop = __libposix_get_errno(PosixESRCH);
return -1;
}
ret = postnote(mode, pid, msg);
if(ret != 0){
*errnop = __libposix_translate_errstr((uintptr_t)POSIX_kill);
return -1;
}
return 0;
}
static int
translate_jehanne_note(char *note)
{
// TODO: implement
return 0;
}
static void
terminated_by_signal(int sig)
{
char buf[64];
__libposix_free_wait_list();
snprint(buf, sizeof(buf), __POSIX_EXIT_SIGNAL_PREFIX "%d", sig);
exits(buf);
}
static int
send_control_msg(int pid, char *msg)
{
int fd, n;
char buf[256];
n = snprint(buf, sizeof(buf), "/proc/%d/ctl", pid);
if(n < 0)
goto ErrorBeforeOpen;
fd = open(buf, OWRITE);
if(fd < 0)
goto ErrorBeforeOpen;
n = snprint(buf, sizeof(buf), "%s", msg);
if(n < 0)
goto ErrorAfterOpen;
if(write(fd, buf, n) < n)
goto ErrorAfterOpen;
close(fd);
return 1;
ErrorAfterOpen:
close(fd);
ErrorBeforeOpen:
return 0;
}
int
POSIX_signal_execute(int sig, PosixSignalDisposition action, int pid)
{
switch(action){
case SignalHandled:
return 1;
case TerminateTheProcess:
case TerminateTheProcessAndCoreDump:
terminated_by_signal(sig);
break;
case StopTheProcess:
if(pid < 0)
sysfatal("libposix: signal %d with stop disposition reached process %d", sig, pid);
return send_control_msg(pid, "stop");
case ResumeTheProcess:
if(pid < 0)
sysfatal("libposix: signal %d with continue disposition reached process %d", sig, pid);
return send_control_msg(pid, "start");
}
return 0;
}
int
__libposix_note_handler(void *ureg, char *note)
{
int sig;
PosixSignalDisposition action;
if(strncmp(note, __POSIX_SIGNAL_PREFIX, __POSIX_SIGNAL_PREFIX_LEN) != 0)
return translate_jehanne_note(note); // TODO: should we translate common notes?
sig = atoi(note+__POSIX_SIGNAL_PREFIX_LEN);
action = __libposix_signal_trampoline(sig);
return POSIX_signal_execute(sig, action, -1);
}
int
libposix_set_signal_trampoline(PosixSignalTrampoline trampoline)
{
if(__libposix_initialized())
return 0;
if(trampoline == nil)
return 0;
__libposix_signal_trampoline = trampoline;
return 1;
}
void
__libposix_signal_check_conf(void)
{
if(__libposix_signal_trampoline == nil)
sysfatal("libposix: no signal trampoline");
}