Make the sys logger for so that concurrent logging will work

properly (see tests/syslog_test.c for example).
 -Erik

diff --git a/sysklogd/syslogd.c b/sysklogd/syslogd.c
index 4cfb458ed0cc5295aa8378bbb6cb2a5861f399f0..004e6ab1d452bc7c3da02a320d17ee9d98c3ddd0 100644 (file)
--- a/sysklogd/syslogd.c
+++ b/sysklogd/syslogd.c
@@ -80,14 +80,23 @@ static void message (char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
 static void message (char *fmt, ...)
 {
        int fd;
+       struct flock fl;
        va_list arguments;
 
+       fl.l_whence = SEEK_SET;
+       fl.l_start  = 0;
+       fl.l_len    = 1;
+
        if ((fd = device_open (logFilePath,
                                                   O_WRONLY | O_CREAT | O_NOCTTY | O_APPEND |
                                                   O_NONBLOCK)) >= 0) {
+               fl.l_type = F_WRLCK;
+               fcntl (fd, F_SETLKW, &fl);
                va_start (arguments, fmt);
                vdprintf (fd, fmt, arguments);
                va_end (arguments);
+               fl.l_type = F_UNLCK;
+               fcntl (fd, F_SETLKW, &fl);
                close (fd);
        } else {
                /* Always send console messages to /dev/console so people will see them. */
@@ -173,6 +182,7 @@ static void doSyslogd (void)
        signal (SIGTERM, quit_signal);
        signal (SIGQUIT, quit_signal);
        signal (SIGHUP,  SIG_IGN);
+       signal (SIGCLD,  SIG_IGN);
        signal (SIGALRM, domark);
        alarm (MarkInterval);
 
@@ -216,54 +226,68 @@ static void doSyslogd (void)
 
                for (fd = 0; (n_ready > 0) && (fd < FD_SETSIZE); fd++) {
                        if (FD_ISSET (fd, &readfds)) {
+
                                --n_ready;
+
                                if (fd == sock_fd) {
-                                       int conn;
+
+                                       int   conn;
+                                       pid_t pid;
+
                                        if ((conn = accept (sock_fd, (struct sockaddr *) &sunx, &addrLength)) < 0) {
                                                fatalError ("accept error: %s\n", strerror (errno));
                                        }
-                                       FD_SET (conn, &fds);
-                                       continue;
-                               }
-                               else {
-#                                      define BUFSIZE 1023
-                                       char buf[ BUFSIZE + 1 ];
-                                       int n_read;
 
-                                       while ((n_read = read (fd, buf, BUFSIZE )) > 0) {
+                                       pid = fork();
 
-                                               int pri = (LOG_USER | LOG_NOTICE);
-                                               char line[ BUFSIZE + 1 ];
-                                               unsigned char c;
-                                               char *p = buf, *q = line;
+                                       if (pid < 0) {
+                                               perror ("syslogd: fork");
+                                               close (conn);
+                                               continue;
+                                       }
 
-                                               buf[ n_read - 1 ] = '\0';
+                                       if (pid > 0) {
 
-                                               while (p && (c = *p) && q < &line[ sizeof (line) - 1 ]) {
-                                                       if (c == '<') {
+#                                              define BUFSIZE 1023
+                                               char   buf[ BUFSIZE + 1 ];
+                                               int    n_read;
+
+                                               while ((n_read = read (conn, buf, BUFSIZE )) > 0) {
+
+                                                       int           pri = (LOG_USER | LOG_NOTICE);
+                                                       char          line[ BUFSIZE + 1 ];
+                                                       unsigned char c;
+
+                                                       char *p = buf, *q = line;
+
+                                                       buf[ n_read - 1 ] = '\0';
+
+                                                       while (p && (c = *p) && q < &line[ sizeof (line) - 1 ]) {
+                                                               if (c == '<') {
                                                                /* Parse the magic priority number. */
-                                                               pri = 0;
-                                                               while (isdigit (*(++p))) {
-                                                                       pri = 10 * pri + (*p - '0');
+                                                                       pri = 0;
+                                                                       while (isdigit (*(++p))) {
+                                                                               pri = 10 * pri + (*p - '0');
+                                                                       }
+                                                                       if (pri & ~(LOG_FACMASK | LOG_PRIMASK))
+                                                                               pri = (LOG_USER | LOG_NOTICE);
+                                                               } else if (c == '\n') {
+                                                                       *q++ = ' ';
+                                                               } else if (iscntrl (c) && (c < 0177)) {
+                                                                       *q++ = '^';
+                                                                       *q++ = c ^ 0100;
+                                                               } else {
+                                                                       *q++ = c;
                                                                }
-                                                               if (pri & ~(LOG_FACMASK | LOG_PRIMASK))
-                                                                       pri = (LOG_USER | LOG_NOTICE);
-                                                       } else if (c == '\n') {
-                                                               *q++ = ' ';
-                                                       } else if (iscntrl (c) && (c < 0177)) {
-                                                               *q++ = '^';
-                                                               *q++ = c ^ 0100;
-                                                       } else {
-                                                               *q++ = c;
+                                                               p++;
                                                        }
-                                                       p++;
+                                                       *q = '\0';
+                                                       /* Now log it */
+                                                       logMessage (pri, line);
                                                }
-                                               *q = '\0';
-                                               /* Now log it */
-                                               logMessage (pri, line);
+                                               exit (0);
                                        }
-                                       close (fd);
-                                       FD_CLR (fd, &fds);
+                                       close (conn);
                                }
                        }
                }
@@ -432,9 +456,9 @@ extern int syslogd_main(int argc, char **argv)
 }
 
 /*
- * Local Variables
- * c-file-style: "linux"
- * c-basic-offset: 4
- * tab-width: 4
- * End:
- */
+Local Variables
+c-file-style: "linux"
+c-basic-offset: 4
+tab-width: 4
+End:
+*/

diff --git a/syslogd.c b/syslogd.c
index 4cfb458ed0cc5295aa8378bbb6cb2a5861f399f0..004e6ab1d452bc7c3da02a320d17ee9d98c3ddd0 100644 (file)
--- a/syslogd.c
+++ b/syslogd.c
@@ -80,14 +80,23 @@ static void message (char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
 static void message (char *fmt, ...)
 {
        int fd;
+       struct flock fl;
        va_list arguments;
 
+       fl.l_whence = SEEK_SET;
+       fl.l_start  = 0;
+       fl.l_len    = 1;
+
        if ((fd = device_open (logFilePath,
                                                   O_WRONLY | O_CREAT | O_NOCTTY | O_APPEND |
                                                   O_NONBLOCK)) >= 0) {
+               fl.l_type = F_WRLCK;
+               fcntl (fd, F_SETLKW, &fl);
                va_start (arguments, fmt);
                vdprintf (fd, fmt, arguments);
                va_end (arguments);
+               fl.l_type = F_UNLCK;
+               fcntl (fd, F_SETLKW, &fl);
                close (fd);
        } else {
                /* Always send console messages to /dev/console so people will see them. */
@@ -173,6 +182,7 @@ static void doSyslogd (void)
        signal (SIGTERM, quit_signal);
        signal (SIGQUIT, quit_signal);
        signal (SIGHUP,  SIG_IGN);
+       signal (SIGCLD,  SIG_IGN);
        signal (SIGALRM, domark);
        alarm (MarkInterval);
 
@@ -216,54 +226,68 @@ static void doSyslogd (void)
 
                for (fd = 0; (n_ready > 0) && (fd < FD_SETSIZE); fd++) {
                        if (FD_ISSET (fd, &readfds)) {
+
                                --n_ready;
+
                                if (fd == sock_fd) {
-                                       int conn;
+
+                                       int   conn;
+                                       pid_t pid;
+
                                        if ((conn = accept (sock_fd, (struct sockaddr *) &sunx, &addrLength)) < 0) {
                                                fatalError ("accept error: %s\n", strerror (errno));
                                        }
-                                       FD_SET (conn, &fds);
-                                       continue;
-                               }
-                               else {
-#                                      define BUFSIZE 1023
-                                       char buf[ BUFSIZE + 1 ];
-                                       int n_read;
 
-                                       while ((n_read = read (fd, buf, BUFSIZE )) > 0) {
+                                       pid = fork();
 
-                                               int pri = (LOG_USER | LOG_NOTICE);
-                                               char line[ BUFSIZE + 1 ];
-                                               unsigned char c;
-                                               char *p = buf, *q = line;
+                                       if (pid < 0) {
+                                               perror ("syslogd: fork");
+                                               close (conn);
+                                               continue;
+                                       }
 
-                                               buf[ n_read - 1 ] = '\0';
+                                       if (pid > 0) {
 
-                                               while (p && (c = *p) && q < &line[ sizeof (line) - 1 ]) {
-                                                       if (c == '<') {
+#                                              define BUFSIZE 1023
+                                               char   buf[ BUFSIZE + 1 ];
+                                               int    n_read;
+
+                                               while ((n_read = read (conn, buf, BUFSIZE )) > 0) {
+
+                                                       int           pri = (LOG_USER | LOG_NOTICE);
+                                                       char          line[ BUFSIZE + 1 ];
+                                                       unsigned char c;
+
+                                                       char *p = buf, *q = line;
+
+                                                       buf[ n_read - 1 ] = '\0';
+
+                                                       while (p && (c = *p) && q < &line[ sizeof (line) - 1 ]) {
+                                                               if (c == '<') {
                                                                /* Parse the magic priority number. */
-                                                               pri = 0;
-                                                               while (isdigit (*(++p))) {
-                                                                       pri = 10 * pri + (*p - '0');
+                                                                       pri = 0;
+                                                                       while (isdigit (*(++p))) {
+                                                                               pri = 10 * pri + (*p - '0');
+                                                                       }
+                                                                       if (pri & ~(LOG_FACMASK | LOG_PRIMASK))
+                                                                               pri = (LOG_USER | LOG_NOTICE);
+                                                               } else if (c == '\n') {
+                                                                       *q++ = ' ';
+                                                               } else if (iscntrl (c) && (c < 0177)) {
+                                                                       *q++ = '^';
+                                                                       *q++ = c ^ 0100;
+                                                               } else {
+                                                                       *q++ = c;
                                                                }
-                                                               if (pri & ~(LOG_FACMASK | LOG_PRIMASK))
-                                                                       pri = (LOG_USER | LOG_NOTICE);
-                                                       } else if (c == '\n') {
-                                                               *q++ = ' ';
-                                                       } else if (iscntrl (c) && (c < 0177)) {
-                                                               *q++ = '^';
-                                                               *q++ = c ^ 0100;
-                                                       } else {
-                                                               *q++ = c;
+                                                               p++;
                                                        }
-                                                       p++;
+                                                       *q = '\0';
+                                                       /* Now log it */
+                                                       logMessage (pri, line);
                                                }
-                                               *q = '\0';
-                                               /* Now log it */
-                                               logMessage (pri, line);
+                                               exit (0);
                                        }
-                                       close (fd);
-                                       FD_CLR (fd, &fds);
+                                       close (conn);
                                }
                        }
                }
@@ -432,9 +456,9 @@ extern int syslogd_main(int argc, char **argv)
 }
 
 /*
- * Local Variables
- * c-file-style: "linux"
- * c-basic-offset: 4
- * tab-width: 4
- * End:
- */
+Local Variables
+c-file-style: "linux"
+c-basic-offset: 4
+tab-width: 4
+End:
+*/

diff --git a/tests/.cvsignore b/tests/.cvsignore
index 5f845231349e0cbf779c17e698a6fc3adaad955b..3645cf92feaaecfa7e5efb8779ec7783f558fdb3 100644 (file)
--- a/tests/.cvsignore
+++ b/tests/.cvsignore
@@ -13,3 +13,4 @@ mv
 mv_*.bb
 mv_*.gnu
 mv_tests
+syslog_test

diff --git a/tests/Makefile b/tests/Makefile
index c4fb0e9119d2995db895ec9c079797859781e366..508bc64f262ea30264c76d659b1334cb09ca3639 100644 (file)
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -29,3 +29,5 @@ BBL := $(shell pushd .. >/dev/null &&         \
 ${BBL}: ../busybox
        rm -f $@
        ln ../busybox $@
+
+syslog_test: syslog_test.c

diff --git a/tests/syslog_test.c b/tests/syslog_test.c
new file mode 100644 (file)
index 0000000..fb4c691
--- /dev/null
+++ b/tests/syslog_test.c
@@ -0,0 +1,19 @@
+#include <syslog.h>
+
+int do_log(char* msg, int delay)
+{
+  openlog("testlog", LOG_PID, LOG_DAEMON);
+  while(1) {
+    syslog(LOG_ERR, "%s: testing one, two, three\n", msg);
+    sleep(delay);
+  }
+  closelog();
+  return(0);
+};
+
+int main(void)
+{
+  if (fork()==0)
+    do_log("A", 2);
+  do_log("B", 3);
+}