From b70505fd58b5de4026754c9ea9a3d4cdc5bd4e3a Mon Sep 17 00:00:00 2001
From: Paul Lietar <paul@lietar.net>
Date: Tue, 11 Jun 2013 15:33:36 +0200
Subject: [PATCH] Support log redirection to a file.

---
 common.h    |  2 ++
 shairport.c | 56 +++++++++++++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 56 insertions(+), 2 deletions(-)

diff --git a/common.h b/common.h
index c16608ff..6202f436 100644
--- a/common.h
+++ b/common.h
@@ -28,6 +28,8 @@ typedef struct {
     int mdns_internal;
     char *cmd_start, *cmd_stop;
     char *pidfile;
+    char *logfile;
+    char *errfile;
 } shairport_cfg;
 
 extern int debuglev;
diff --git a/shairport.c b/shairport.c
index 8afd12bf..f5906e7e 100644
--- a/shairport.c
+++ b/shairport.c
@@ -30,11 +30,15 @@
 #include <memory.h>
 #include <openssl/md5.h>
 #include <sys/wait.h>
+#include <getopt.h>
 #include "common.h"
+#include "daemon.h"
 #include "rtsp.h"
 #include "mdns.h"
 #include "getopt_long.h"
 
+static void log_setup();
+
 static int shutting_down = 0;
 void shairport_shutdown(void) {
     if (shutting_down)
@@ -44,6 +48,8 @@ void shairport_shutdown(void) {
     mdns_unregister();
     rtsp_shutdown_stream();
     config.output->deinit();
+    daemon_exit(); // This does nothing if not in daemon mode
+
     exit(0);
 }
 
@@ -62,6 +68,10 @@ static void sig_child(int foo, siginfo_t *bar, void *baz) {
     }
 }
 
+static void sig_logrotate(int foo, siginfo_t *bar, void *baz) {
+    log_setup();
+}
+
 void usage(char *progname) {
     printf("Usage: %s [options...]\n", progname);
     printf("  or:  %s [options...] -- [audio output-specific options]\n", progname);
@@ -80,6 +90,9 @@ void usage(char *progname) {
     printf("                        written to stdout\n");
     printf("    -P, --pidfile=FILE  write daemon's pid to FILE on startup.\n");
     printf("                        Has no effect if -d is not specified\n");
+    printf("    -l, --log FILE      redirect shairport's standard output to FILE\n");
+    printf("                        If --errror is not specified, it also redirects error output to FILE\n");
+    printf("    -e, --error FILE    redirect shairport's standard error output to FILE\n");
     printf("    -B, --on-start=COMMAND  run a shell command when playback begins\n");
     printf("    -E, --on-stop=COMMAND   run a shell command when playback ends\n");
 
@@ -97,6 +110,8 @@ int parse_options(int argc, char **argv) {
         {"help",    no_argument,        NULL, 'h'},
         {"daemon",  no_argument,        NULL, 'd'},
         {"pidfile", required_argument,  NULL, 'P'},
+        {"log",     required_argument,  NULL, 'l'},
+        {"error",   required_argument,  NULL, 'e'},
         {"port",    required_argument,  NULL, 'p'},
         {"name",    required_argument,  NULL, 'a'},
         {"output",  required_argument,  NULL, 'o'},
@@ -107,7 +122,7 @@ int parse_options(int argc, char **argv) {
 
     int opt;
     while ((opt = getopt_long(argc, argv,
-                              "+hdvP:p:a:o:b:B:E:",
+                              "+hdvP:l:e:p:a:o:b:B:E:",
                               long_options, NULL)) > 0) {
         switch (opt) {
             default:
@@ -138,9 +153,15 @@ int parse_options(int argc, char **argv) {
             case 'E':
                 config.cmd_stop = optarg;
                 break;
-            case 'f':
+            case 'P':
                 config.pidfile = optarg;
                 break;
+            case 'l':
+                config.logfile = optarg;
+                break;
+            case 'e':
+                config.errfile = optarg;
+                break;
         }
     }
     return optind;
@@ -154,6 +175,7 @@ void signal_setup(void) {
     sigfillset(&set);
     sigdelset(&set, SIGINT);
     sigdelset(&set, SIGTERM);
+    sigdelset(&set, SIGHUP);
     sigdelset(&set, SIGSTOP);
     sigdelset(&set, SIGCHLD);
     pthread_sigmask(SIG_BLOCK, &set, NULL);
@@ -169,6 +191,9 @@ void signal_setup(void) {
     sigaction(SIGINT, &sa, NULL);
     sigaction(SIGTERM, &sa, NULL);
 
+    sa.sa_sigaction = &sig_logrotate;
+    sigaction(SIGHUP, &sa, NULL);
+
     sa.sa_flags = SA_SIGINFO;
     sa.sa_sigaction = &sig_child;
     sigaction(SIGCHLD, &sa, NULL);
@@ -182,6 +207,30 @@ void shairport_startup_complete(void) {
     }
 }
 
+void log_setup() {
+    if (config.logfile) {
+        int log_fd = open(config.logfile,
+                O_WRONLY | O_CREAT | O_APPEND,
+                S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
+        if (log_fd < 0)
+            die("Could not open logfile");
+
+        dup2(log_fd, STDOUT_FILENO);
+        if (!config.errfile)
+            dup2(log_fd, STDERR_FILENO);
+    }
+
+    if (config.errfile) {
+        int err_fd = open(config.errfile,
+                O_WRONLY | O_CREAT | O_APPEND,
+                S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
+        if (err_fd < 0)
+            die("Could not open logfile");
+
+        dup2(err_fd, STDERR_FILENO);
+    }
+}
+
 int main(int argc, char **argv) {
     signal_setup();
     memset(&config, 0, sizeof(config));
@@ -201,11 +250,14 @@ int main(int argc, char **argv) {
         daemon_init();
     }
 
+    log_setup();
+
     config.output = audio_get_output(config.output_name);
     if (!config.output) {
         audio_ls_outputs();
         die("Invalid audio output specified!");
     }
+
     config.output->init(argc-audio_arg, argv+audio_arg);
 
     uint8_t ap_md5[16];