signals: New function signal_name().

[sliver-openvswitch.git] / lib / process.c

diff --git a/lib/process.c b/lib/process.c
index 1fe3c12..f772833 100644 (file)
--- a/lib/process.c
+++ b/lib/process.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2009 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -30,12 +30,18 @@
 #include "fatal-signal.h"
 #include "list.h"
 #include "poll-loop.h"
+#include "signals.h"
 #include "socket-util.h"
 #include "util.h"
-
-#define THIS_MODULE VLM_process
 #include "vlog.h"
 
+VLOG_DEFINE_THIS_MODULE(process);
+
+COVERAGE_DEFINE(process_run);
+COVERAGE_DEFINE(process_run_capture);
+COVERAGE_DEFINE(process_sigchld);
+COVERAGE_DEFINE(process_start);
+
 struct process {
     struct list node;
     char *name;
@@ -55,7 +61,7 @@ static struct list all_processes = LIST_INITIALIZER(&all_processes);
 static bool sigchld_is_blocked(void);
 static void block_sigchld(sigset_t *);
 static void unblock_sigchld(const sigset_t *);
-static void sigchld_handler(int signr UNUSED);
+static void sigchld_handler(int signr OVS_UNUSED);
 static bool is_member(int x, const int *array, size_t);
 
 /* Initializes the process subsystem (if it is not already initialized).  Calls
@@ -103,7 +109,7 @@ process_escape_args(char **argv)
         if (argp != argv) {
             ds_put_char(&ds, ' ');
         }
-        if (arg[strcspn(arg, " \t\r\n\v\\")]) {
+        if (arg[strcspn(arg, " \t\r\n\v\\\'\"")]) {
             ds_put_char(&ds, '"');
             for (p = arg; *p; p++) {
                 if (*p == '\\' || *p == '\"') {
@@ -161,7 +167,7 @@ process_register(const char *name, pid_t pid)
 
     assert(sigchld_is_blocked());
 
-    p = xcalloc(1, sizeof *p);
+    p = xzalloc(sizeof *p);
     p->pid = pid;
     slash = strrchr(name, '/');
     p->name = xstrdup(slash ? slash + 1 : name);
@@ -190,6 +196,7 @@ process_start(char **argv,
               struct process **pp)
 {
     sigset_t oldsigs;
+    int nullfd;
     pid_t pid;
     int error;
 
@@ -200,18 +207,24 @@ process_start(char **argv,
         return error;
     }
 
+    if (n_null_fds) {
+        nullfd = get_null_fd();
+        if (nullfd < 0) {
+            return -nullfd;
+        }
+    } else {
+        nullfd = -1;
+    }
+
     block_sigchld(&oldsigs);
-    fatal_signal_block();
     pid = fork();
     if (pid < 0) {
-        fatal_signal_unblock();
         unblock_sigchld(&oldsigs);
         VLOG_WARN("fork failed: %s", strerror(errno));
         return errno;
     } else if (pid) {
         /* Running in parent process. */
         *pp = process_register(argv[0], pid);
-        fatal_signal_unblock();
         unblock_sigchld(&oldsigs);
         return 0;
     } else {
@@ -220,19 +233,20 @@ process_start(char **argv,
         int fd;
 
         fatal_signal_fork();
-        fatal_signal_unblock();
         unblock_sigchld(&oldsigs);
         for (fd = 0; fd < fd_max; fd++) {
             if (is_member(fd, null_fds, n_null_fds)) {
-                /* We can't use get_null_fd() here because we might have
-                 * already closed its fd. */
-                int nullfd = open("/dev/null", O_RDWR);
                 dup2(nullfd, fd);
-                close(nullfd);
-            } else if (fd >= 3 && !is_member(fd, keep_fds, n_keep_fds)) {
+            } else if (fd >= 3 && fd != nullfd
+                       && !is_member(fd, keep_fds, n_keep_fds)) {
                 close(fd);
             }
         }
+        if (nullfd >= 0
+            && !is_member(nullfd, keep_fds, n_keep_fds)
+            && !is_member(nullfd, null_fds, n_null_fds)) {
+            close(nullfd);
+        }
         execvp(argv[0], argv);
         fprintf(stderr, "execvp(\"%s\") failed: %s\n",
                 argv[0], strerror(errno));
@@ -289,7 +303,7 @@ process_exited(struct process *p)
         return true;
     } else {
         char buf[_POSIX_PIPE_BUF];
-        read(fds[0], buf, sizeof buf);
+        ignore(read(fds[0], buf, sizeof buf));
         return false;
     }
 }
@@ -340,17 +354,10 @@ process_status_msg(int status)
     struct ds ds = DS_EMPTY_INITIALIZER;
     if (WIFEXITED(status)) {
         ds_put_format(&ds, "exit status %d", WEXITSTATUS(status));
-    } else if (WIFSIGNALED(status) || WIFSTOPPED(status)) {
-        int signr = WIFSIGNALED(status) ? WTERMSIG(status) : WSTOPSIG(status);
-        const char *name = NULL;
-#ifdef HAVE_STRSIGNAL
-        name = strsignal(signr);
-#endif
-        ds_put_format(&ds, "%s by signal %d",
-                      WIFSIGNALED(status) ? "killed" : "stopped", signr);
-        if (name) {
-            ds_put_format(&ds, " (%s)", name);
-        }
+    } else if (WIFSIGNALED(status)) {
+        ds_put_format(&ds, "killed (%s)", signal_name(WTERMSIG(status)));
+    } else if (WIFSTOPPED(status)) {
+        ds_put_format(&ds, "stopped (%s)", signal_name(WSTOPSIG(status)));
     } else {
         ds_put_format(&ds, "terminated abnormally (%x)", status);
     }
@@ -419,15 +426,13 @@ stream_open(struct stream *s)
 static void
 stream_read(struct stream *s)
 {
-    int error = 0;
-
     if (s->fds[0] < 0) {
         return;
     }
 
-    error = 0;
     for (;;) {
         char buffer[512];
+        int error;
         size_t n;
 
         error = read_fully(s->fds[0], buffer, sizeof buffer, &n);
@@ -521,12 +526,10 @@ process_run_capture(char **argv, char **stdout_log, char **stderr_log,
     }
 
     block_sigchld(&oldsigs);
-    fatal_signal_block();
     pid = fork();
     if (pid < 0) {
-        int error = errno;
+        error = errno;
 
-        fatal_signal_unblock();
         unblock_sigchld(&oldsigs);
         VLOG_WARN("fork failed: %s", strerror(error));
 
@@ -539,7 +542,6 @@ process_run_capture(char **argv, char **stdout_log, char **stderr_log,
         struct process *p;
 
         p = process_register(argv[0], pid);
-        fatal_signal_unblock();
         unblock_sigchld(&oldsigs);
 
         close(s_stdout.fds[1]);
@@ -575,7 +577,6 @@ process_run_capture(char **argv, char **stdout_log, char **stderr_log,
         int i;
 
         fatal_signal_fork();
-        fatal_signal_unblock();
         unblock_sigchld(&oldsigs);
 
         dup2(get_null_fd(), 0);
@@ -595,12 +596,12 @@ process_run_capture(char **argv, char **stdout_log, char **stderr_log,
 }
 \f
 static void
-sigchld_handler(int signr UNUSED)
+sigchld_handler(int signr OVS_UNUSED)
 {
     struct process *p;
 
     COVERAGE_INC(process_sigchld);
-    LIST_FOR_EACH (p, struct process, node, &all_processes) {
+    LIST_FOR_EACH (p, node, &all_processes) {
         if (!p->exited) {
             int retval, status;
             do {
@@ -617,7 +618,7 @@ sigchld_handler(int signr UNUSED)
             }
         }
     }
-    write(fds[1], "", 1);
+    ignore(write(fds[1], "", 1));
 }
 
 static bool