Make PID directory path creation recursive and tidy up some code formatting.

common.h

@@ -119,7 +119,7 @@ typedef struct {
   int daemonise_store_pid; // don't try to save a PID file
   char *piddir;
   char *computed_piddir; // the actual pid directory to create, if any
-  int logOutputLevel; // log output level
+  int logOutputLevel;    // log output level
   int statistics_requested, use_negotiated_latencies;
   enum playback_mode_type playback_mode;
   char *cmd_start, *cmd_stop, *cmd_set_volume;

mdns_dns_sd.c

@@ -24,8 +24,8 @@
  * OTHER DEALINGS IN THE SOFTWARE.
  */
 
-#include "mdns.h"
 #include "common.h"
+#include "mdns.h"
 #include <arpa/inet.h>
 #include <dns_sd.h>
 #include <stdlib.h>

mdns_external.c

@@ -24,8 +24,8 @@
  * OTHER DEALINGS IN THE SOFTWARE.
  */
 
-#include "mdns.h"
 #include "common.h"
+#include "mdns.h"
 #include <errno.h>
 #include <fcntl.h>
 #include <signal.h>

shairport.c

@@ -114,6 +114,54 @@ static void sig_connect_audio_output(int foo, siginfo_t *bar, void *baz) {
   set_requested_connection_state_to_output(1);
 }
 
+// The following two functions are adapted slightly and with thanks from Jonathan Leffler's sample
+// code at
+// https://stackoverflow.com/questions/675039/how-can-i-create-directory-tree-in-c-linux
+
+int do_mkdir(const char *path, mode_t mode) {
+  struct stat st;
+  int status = 0;
+
+  if (stat(path, &st) != 0) {
+    /* Directory does not exist. EEXIST for race condition */
+    if (mkdir(path, mode) != 0 && errno != EEXIST)
+      status = -1;
+  } else if (!S_ISDIR(st.st_mode)) {
+    errno = ENOTDIR;
+    status = -1;
+  }
+
+  return (status);
+}
+
+// mkpath - ensure all directories in path exist
+// Algorithm takes the pessimistic view and works top-down to ensure
+// each directory in path exists, rather than optimistically creating
+// the last element and working backwards.
+
+int mkpath(const char *path, mode_t mode) {
+  char *pp;
+  char *sp;
+  int status;
+  char *copypath = strdup(path);
+
+  status = 0;
+  pp = copypath;
+  while (status == 0 && (sp = strchr(pp, '/')) != 0) {
+    if (sp != pp) {
+      /* Neither root nor double slash in path */
+      *sp = '\0';
+      status = do_mkdir(copypath, mode);
+      *sp = '/';
+    }
+    pp = sp + 1;
+  }
+  if (status == 0)
+    status = do_mkdir(path, mode);
+  free(copypath);
+  return (status);
+}
+
 char *get_version_string() {
   char *version_string = malloc(200);
   if (version_string) {
@@ -893,8 +941,8 @@ int parse_options(int argc, char **argv) {
   free(i2);
   free(i3);
   free(vs);
-  
-  // now, check and calculate the pid directory
+
+// now, check and calculate the pid directory
 #ifdef USE_CUSTOM_PID_DIR
   char *use_this_pid_dir = PIDDIR;
 #else
@@ -954,7 +1002,7 @@ void shairport_startup_complete(void) {
 }
 
 const char *pid_file_proc(void) {
-  
+
   char fn[8192];
   snprintf(fn, sizeof(fn), "%s/%s.pid", config.computed_piddir,
            daemon_pid_file_ident ? daemon_pid_file_ident : "unknown");
@@ -1180,10 +1228,23 @@ int main(int argc, char **argv) {
         return 255;
       }
 
-      if (ret != 0)
-        daemon_log(ret != 0 ? LOG_ERR : LOG_INFO, "Daemon returned %i as return value.", ret);
+      switch (ret) {
+      case 0:
+        break;
+      case 1:
+        daemon_log(LOG_ERR,
+                   "daemon failed to launch: could not close open file descriptors after forking.");
+        break;
+      case 2:
+        daemon_log(LOG_ERR, "daemon failed to launch: could not create PID file.");
+        break;
+      case 3:
+        daemon_log(LOG_ERR, "daemon failed to launch: could not create or access PID directory.");
+        break;
+      default:
+        daemon_log(LOG_ERR, "daemon failed to launch, error %i.", ret);
+      }
       return ret;
-
     } else { /* The daemon */
 
       /* Close FDs */
@@ -1198,7 +1259,13 @@ int main(int argc, char **argv) {
       /* Create the PID file if required */
       if (config.daemonise_store_pid) {
         /* Create the PID directory if required -- we don't really care about the result */
-        mkdir(config.computed_piddir, 0700);
+        printf("PID directory is \"%s\".", config.computed_piddir);
+        int result = mkpath(config.computed_piddir, 0700);
+        if ((result != 0) && (result != -EEXIST)) {
+          // error creating or accessing the PID file directory
+          daemon_retval_send(3);
+          goto finish;
+        }
         if (daemon_pid_file_create() < 0) {
           daemon_log(LOG_ERR, "Could not create PID file (%s).", strerror(errno));
           daemon_retval_send(2);