zynaddsubfx

commit 6e7dd4146d2f4bc7a2618000337e7ba35373232d
parent 1b004be9e189fe3b958e198703ce902a1318717c
Author: Johannes Lorenz <[email protected]>
Date:   Sat, 28 Mar 2015 15:07:20 +0100

Appended PID to jack client names.

Diffstat:
M
src/Misc/Util.cpp
 | 
43
+++++++++++++++++++++++++++++++++++++++++--
M
src/Misc/Util.h
 | 
3
+++
M
src/Nio/JackEngine.cpp
 | 
5
+++++
M
src/Nio/JackMultiEngine.cpp
 | 
2
++

4 files changed, 51 insertions(+), 2 deletions(-)
diff --git a/src/Misc/Util.cpp b/src/Misc/Util.cpp
@@ -23,8 +23,9 @@
 #include "Util.h"
 #include <vector>
 #include <cassert>
-#include <math.h>
-#include <stdio.h>
+#include <cmath>
+#include <cstdio>
+#include <fstream>
 #include <err.h>
 
 #include <sys/types.h>
@@ -136,6 +137,43 @@ void os_sleep(long length)
     usleep(length);
 }
 
+//!< maximum lenght a pid has on any POSIX system
+//!< this is an estimation, but more than 12 looks insane
+constexpr std::size_t max_pid_len = 12;
+
+//!< safe pid lenght guess, posix conform
+std::size_t os_guess_pid_length()
+{
+    const char* pid_max_file = "/proc/sys/kernel/pid_max";
+    if(-1 == access(pid_max_file, R_OK)) {
+        return max_pid_len;
+    }
+    else {
+        std::ifstream is(pid_max_file);
+        if(!is.good())
+            return max_pid_len;
+        else {
+            std::string s;
+            is >> s;
+            for(const auto& c : s)
+                if(c < '0' || c > '9')
+                    return max_pid_len;
+            return std::min(s.length(), max_pid_len);
+        }
+    }
+}
+
+//!< returns pid padded, posix conform
+std::string os_pid_as_padded_string()
+{
+    char result_str[max_pid_len << 1];
+    std::fill_n(result_str, max_pid_len, '0');
+    std::size_t written = snprintf(result_str + max_pid_len, max_pid_len,
+        "%d", (int)getpid());
+    // the below pointer should never cause segfaults:
+    return result_str + max_pid_len + written - os_guess_pid_length();
+}
+
 std::string legalizeFilename(std::string filename)
 {
     for(int i = 0; i < (int) filename.size(); ++i) {
@@ -179,3 +217,4 @@ const char *message_snip(const char *m)
     while(*m && *m!='/')++m;
     return *m?m+1:m;
 }
+
diff --git a/src/Misc/Util.h b/src/Misc/Util.h
@@ -52,6 +52,9 @@ void set_realtime();
 /**Os independent sleep in microsecond*/
 void os_sleep(long length);
 
+//! returns pid padded to maximum pid lenght, posix conform
+std::string os_pid_as_padded_string();
+
 std::string legalizeFilename(std::string filename);
 
 extern float *denormalkillbuf; /**<the buffer to add noise in order to avoid denormalisation*/
diff --git a/src/Nio/JackEngine.cpp b/src/Nio/JackEngine.cpp
@@ -30,10 +30,13 @@
 #include <sys/stat.h>
 #include <cassert>
 #include <cstring>
+#include <unistd.h> // access()
+#include <fstream> // std::istream
 
 #include "Nio.h"
 #include "OutMgr.h"
 #include "InMgr.h"
+#include "Misc/Util.h"
 
 #include "JackEngine.h"
 
@@ -65,6 +68,8 @@ bool JackEngine::connectServer(string server)
     string postfix    = Nio::getPostfix();
     if(!postfix.empty())
         clientname += "_" + postfix;
+    clientname += "_" + os_pid_as_padded_string();
+
     jack_status_t jackstatus;
     bool use_server_name = server.size() && server.compare("default") != 0;
     jack_options_t jopts = (jack_options_t)
diff --git a/src/Nio/JackMultiEngine.cpp b/src/Nio/JackMultiEngine.cpp
@@ -28,6 +28,7 @@
 #include <cassert>
 
 #include "Nio.h"
+#include "Misc/Util.h"
 #include "../Misc/Master.h"
 #include "../Misc/Part.h"
 #include "../Misc/MiddleWare.h"
@@ -82,6 +83,7 @@ bool JackMultiEngine::Start(void)
     string postfix    = Nio::getPostfix();
     if(!postfix.empty())
         clientname += "_" + postfix;
+    clientname += "_" + os_pid_as_padded_string();
     jack_status_t jackstatus;
 
     impl->client = jack_client_open(clientname.c_str(), JackNullOption, &jackstatus);