lxc-start to report exit code of started application

The exit code of the application as reported by lxc-start is:
0-126       exit code of the application itself
128+n       signal n received by the application
255         lxc error

Signed-off-by: Michel Normand <normand@fr.ibm.com>
Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>

diff --git a/src/lxc/error.c b/src/lxc/error.c
index 153d89fcf2f95ebbf4c011368c982fcd7e8788ab..9a6634472c77c4fc292a720f55d1a498494ca78c 100644 (file)
--- a/src/lxc/error.c
+++ b/src/lxc/error.c
@@ -23,7 +23,11 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <sys/wait.h>
 #include "error.h"
+#include "log.h"
+
+lxc_log_define(lxc_error, lxc);
 
 static const char *const catalogue[] = {
 
@@ -67,3 +71,32 @@ const char *const lxc_strerror(int error)
 
        return catalogue[error];
 }
+
+/*---------------------------------------------------------------------------*/
+/* lxc_error_set_and_log
+ * function is here to convert
+ * the reported status to an exit code as detailed here:
+ *
+ *   0-126       exit code of the application
+ *   128+n       signal n received by the application
+ *   255         lxc error
+ */
+extern int  lxc_error_set_and_log(int pid, int status)
+{
+       int ret = 0;
+
+       if (WIFEXITED(status)) {
+               ret = WEXITSTATUS(status);
+               if (ret)
+                       INFO("child <%d> ended on error (%d)", pid, ret);
+       }
+
+       if (WIFSIGNALED(status)) {
+               int signal = WTERMSIG(status);
+               ret = ret + 128 + signal;
+
+               INFO("child <%d> ended on signal (%d)", pid, signal);
+       }
+
+       return ret;
+}

diff --git a/src/lxc/error.h b/src/lxc/error.h
index 94c8071d2ac3fa8ce3ee36804b7e947b1c915888..3cbbb20ed440c7d41c908747dd6c95b1dc45bbda 100644 (file)
--- a/src/lxc/error.h
+++ b/src/lxc/error.h
@@ -59,4 +59,5 @@ typedef enum {
        LXC_LAST_ERROR,
 } lxc_error_t;
 
+extern int  lxc_error_set_and_log(int pid, int status);
 #endif

diff --git a/src/lxc/lxc_start.c b/src/lxc/lxc_start.c
index 3f8741f5659e9b5424ba5bbd33998e8dc292dc79..cfdb17a37c26d40d783d0f9f51dd6df69b0ea86b 100644 (file)
--- a/src/lxc/lxc_start.c
+++ b/src/lxc/lxc_start.c
@@ -61,7 +61,7 @@ Options :\n\
 int main(int argc, char *argv[])
 {
        char *const *args;
-       int err;
+       int err = -1;
        struct termios tios;
 
        char *const default_args[] = {
@@ -69,9 +69,8 @@ int main(int argc, char *argv[])
                '\0',
        };
 
-       err = lxc_arguments_parse(&my_args, argc, argv);
-       if (err)
-               return 1;
+       if (lxc_arguments_parse(&my_args, argc, argv))
+               return err;
 
        if (!my_args.argc)
                args = default_args; 
@@ -80,19 +79,15 @@ int main(int argc, char *argv[])
 
        if (lxc_log_init(my_args.log_file, my_args.log_priority,
                         my_args.progname, my_args.quiet))
-               return 1;
+               return err;
 
        if (tcgetattr(0, &tios)) {
                ERROR("failed to get current terminal settings : %s",
                      strerror(errno));
-               return 1;
+               return err;
        }
 
        err = lxc_start(my_args.name, args);
-       if (err) {
-               ERROR("failed to start '%s'", my_args.name);
-               err = 1;
-       }
 
        if (tcsetattr(0, TCSAFLUSH, &tios))
                ERROR("failed to restore terminal settings : %s",

diff --git a/src/lxc/start.c b/src/lxc/start.c
index 83aff9ababfe665510f7795a19b71b33970daffe..392cdd1b2f5ee109b6cc153da6a3f830e7cc5e10 100644 (file)
--- a/src/lxc/start.c
+++ b/src/lxc/start.c
@@ -439,7 +439,7 @@ int lxc_spawn(const char *name, struct lxc_handler *handler, char *const argv[])
 
                if (sigprocmask(SIG_SETMASK, &handler->oldmask, NULL)) {
                        SYSERROR("failed to set sigprocmask");
-                       return -1;
+                       goto out_child;
                }
 
                close(sv[1]);
@@ -460,12 +460,9 @@ int lxc_spawn(const char *name, struct lxc_handler *handler, char *const argv[])
                }
 
                /* Setup the container, ip, names, utsname, ... */
-               err = lxc_setup(name, handler->tty, &handler->tty_info);
-               if (err) {
+               if (lxc_setup(name, handler->tty, &handler->tty_info)) {
                        ERROR("failed to setup the container");
-                       if (write(sv[0], &err, sizeof(err)) < 0)
-                               SYSERROR("failed to write the socket");
-                       goto out_child;
+                       goto out_warn_father;
                }
 
                if (prctl(PR_CAPBSET_DROP, CAP_SYS_BOOT, 0, 0, 0)) {
@@ -476,11 +473,10 @@ int lxc_spawn(const char *name, struct lxc_handler *handler, char *const argv[])
                execvp(argv[0], argv);
                SYSERROR("failed to exec %s", argv[0]);
 
-               err = LXC_ERROR_WRONG_COMMAND;
+       out_warn_father:
                /* If the exec fails, tell that to our father */
                if (write(sv[0], &err, sizeof(err)) < 0)
                        SYSERROR("failed to write the socket");
-               
        out_child:
                exit(err);
        }
@@ -509,8 +505,7 @@ int lxc_spawn(const char *name, struct lxc_handler *handler, char *const argv[])
        }
 
        /* Wait for the child to exec or returning an error */
-       err = read(sv[1], &sync, sizeof(sync));
-       if (err < 0) {
+       if (read(sv[1], &sync, sizeof(sync)) < 0) {
                ERROR("failed to read the socket");
                goto out_abort;
        }
@@ -542,7 +537,7 @@ out_abort:
 int lxc_start(const char *name, char *const argv[])
 {
        struct lxc_handler handler = { 0 };
-       int err = -LXC_ERROR_INTERNAL;
+       int err = -1;
        int status;
 
        if (lxc_init(name, &handler)) {
@@ -556,14 +551,16 @@ int lxc_start(const char *name, char *const argv[])
                goto out;
        }
 
-       if (lxc_poll(name, &handler)) {
+       err = lxc_poll(name, &handler);
+       if (err) {
                ERROR("mainloop exited with an error");
                goto out_abort;
        }
 
        while (waitpid(handler.pid, &status, 0) < 0 && errno == EINTR)
                continue;
-       err = 0;
+
+       err =  lxc_error_set_and_log(handler.pid, status);
 out:
        lxc_fini(name, &handler);
        return err;