added -P <pidfile> to write a PID file on successfull spawning

git-svn-id: svn://svn.lighttpd.net/lighttpd/branches/lighttpd-1.3.x@400 152afb58-edef-0310-8abb-c4023f1b3aa9

src/spawn-fcgi.c

@@ -1,11 +1,14 @@
 #include <sys/types.h>
 #include <sys/time.h>
+#include <sys/stat.h>
 
 #include <stdlib.h>
 #include <string.h>
 #include <errno.h>
 #include <stdio.h>
 #include <unistd.h>
+#include <fcntl.h>
+
 #include "config.h"
 
 #ifdef HAVE_PWD_H
@@ -35,7 +38,7 @@ typedef int socklen_t;
 #endif
 
 #ifdef HAVE_SYS_UN_H
-int fcgi_spawn_connection(char *appPath, unsigned short port, const char *unixsocket, int child_count) {
+int fcgi_spawn_connection(char *appPath, unsigned short port, const char *unixsocket, int child_count, int pid_fd) {
 	int fcgi_fd;
 	int socket_type, status;
 	struct timeval tv = { 0, 100 * 1000 };
@@ -159,6 +162,19 @@ int fcgi_spawn_connection(char *appPath, unsigned short port, const char *unixso
 				fprintf(stderr, "%s.%d: child spawned successfully: PID: %d\n", 
 					__FILE__, __LINE__,
 					child);
+				
+				/* write pid file */
+				if (pid_fd != -1) {
+					/* assume a 32bit pid_t */
+					char pidbuf[12];
+					
+					snprintf(pidbuf, sizeof(pidbuf) - 1, "%d", child);
+					
+					write(pid_fd, pidbuf, strlen(pidbuf));
+					close(pid_fd);
+					pid_fd = -1;
+				}
+				
 				break;
 			case -1:
 				break;
@@ -208,6 +224,7 @@ void show_help () {
 " -p <port>    bind to tcp-port\n" \
 " -s <path>    bind to unix-domain socket\n" \
 " -C <childs>  (PHP only) numbers of childs to spawn (default 5)\n" \
+" -P <path>    name of PID-file for spawed process\n" \
 " -v           show version\n" \
 " -h           show this help\n" \
 "(root only)\n" \
@@ -220,14 +237,16 @@ void show_help () {
 
 
 int main(int argc, char **argv) {
-	char *fcgi_app = NULL, *changeroot = NULL, *username = NULL, *groupname = NULL, *unixsocket = NULL;
+	char *fcgi_app = NULL, *changeroot = NULL, *username = NULL, 
+		*groupname = NULL, *unixsocket = NULL, *pid_file = NULL;
 	unsigned short port = 0;
 	int child_count = 5;
 	int i_am_root, o;
+	int pid_fd = -1;
 	
 	i_am_root = (getuid() == 0);
 	
-	while(-1 != (o = getopt(argc, argv, "c:f:g:hp:u:vC:s:"))) {
+	while(-1 != (o = getopt(argc, argv, "c:f:g:hp:u:vC:s:P:"))) {
 		switch(o) {
 		case 'f': fcgi_app = optarg; break;
 		case 'p': port = strtol(optarg, NULL, 10);/* port */ break;
@@ -236,6 +255,7 @@ int main(int argc, char **argv) {
 		case 'c': if (i_am_root) { changeroot = optarg; }/* chroot() */ break;
 		case 'u': if (i_am_root) { username = optarg; } /* set user */ break;
 		case 'g': if (i_am_root) { groupname = optarg; } /* set group */ break;
+		case 'P': pid_file = optarg; /* PID file */ break;
 		case 'v': show_version(); return 0;
 		case 'h': show_help(); return 0;
 		default: 
@@ -276,6 +296,46 @@ int main(int argc, char **argv) {
 		return -1;
 	}
 	
+	if (pid_file && 
+	    (-1 == (pid_fd = open(pid_file, O_WRONLY | O_CREAT | O_EXCL | O_TRUNC, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)))) {
+		struct stat st;
+		if (errno != EEXIST) {
+			fprintf(stderr, "%s.%d: opening pid-file '%s' failed: %s\n", 
+				__FILE__, __LINE__,
+				pid_file, strerror(errno));
+			
+			return -1;
+		}
+		
+		/* ok, file exists */
+		
+		if (0 != stat(pid_file, &st)) {
+			fprintf(stderr, "%s.%d: stating pid-file '%s' failed: %s\n", 
+				__FILE__, __LINE__,
+				pid_file, strerror(errno));
+			
+			return -1;
+		}
+		
+		/* is it a regular file ? */
+		
+		if (!S_ISREG(st.st_mode)) {
+			fprintf(stderr, "%s.%d: pid-file exists and isn't regular file: '%s'\n", 
+				__FILE__, __LINE__,
+				pid_file);
+			
+			return -1;
+		}
+		
+		if (-1 == (pid_fd = open(pid_file, O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH))) {
+			fprintf(stderr, "%s.%d: opening pid-file '%s' failed: %s\n", 
+				__FILE__, __LINE__,
+				pid_file, strerror(errno));
+			
+			return -1;
+		}
+	}
+	
 	if (i_am_root) {
 		struct group *grp = NULL;
 		struct passwd *pwd = NULL;
@@ -337,7 +397,7 @@ int main(int argc, char **argv) {
 		if (username) setuid(pwd->pw_uid);
 	}
 	
-	return fcgi_spawn_connection(fcgi_app, port, unixsocket, child_count);
+	return fcgi_spawn_connection(fcgi_app, port, unixsocket, child_count, pid_fd);
 }
 #else
 int main() {